xref: /OK3568_Linux_fs/kernel/net/netfilter/nf_tables_api.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2007-2009 Patrick McHardy <kaber@trash.net>
4  *
5  * Development of this code funded by Astaro AG (http://www.astaro.com/)
6  */
7 
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/list.h>
11 #include <linux/skbuff.h>
12 #include <linux/netlink.h>
13 #include <linux/vmalloc.h>
14 #include <linux/rhashtable.h>
15 #include <linux/audit.h>
16 #include <linux/netfilter.h>
17 #include <linux/netfilter/nfnetlink.h>
18 #include <linux/netfilter/nf_tables.h>
19 #include <net/netfilter/nf_flow_table.h>
20 #include <net/netfilter/nf_tables_core.h>
21 #include <net/netfilter/nf_tables.h>
22 #include <net/netfilter/nf_tables_offload.h>
23 #include <net/net_namespace.h>
24 #include <net/sock.h>
25 
26 #define NFT_MODULE_AUTOLOAD_LIMIT (MODULE_NAME_LEN - sizeof("nft-expr-255-"))
27 
28 static LIST_HEAD(nf_tables_expressions);
29 static LIST_HEAD(nf_tables_objects);
30 static LIST_HEAD(nf_tables_flowtables);
31 static LIST_HEAD(nf_tables_destroy_list);
32 static DEFINE_SPINLOCK(nf_tables_destroy_list_lock);
33 static u64 table_handle;
34 
35 enum {
36 	NFT_VALIDATE_SKIP	= 0,
37 	NFT_VALIDATE_NEED,
38 	NFT_VALIDATE_DO,
39 };
40 
41 static struct rhltable nft_objname_ht;
42 
43 static u32 nft_chain_hash(const void *data, u32 len, u32 seed);
44 static u32 nft_chain_hash_obj(const void *data, u32 len, u32 seed);
45 static int nft_chain_hash_cmp(struct rhashtable_compare_arg *, const void *);
46 
47 static u32 nft_objname_hash(const void *data, u32 len, u32 seed);
48 static u32 nft_objname_hash_obj(const void *data, u32 len, u32 seed);
49 static int nft_objname_hash_cmp(struct rhashtable_compare_arg *, const void *);
50 
51 static const struct rhashtable_params nft_chain_ht_params = {
52 	.head_offset		= offsetof(struct nft_chain, rhlhead),
53 	.key_offset		= offsetof(struct nft_chain, name),
54 	.hashfn			= nft_chain_hash,
55 	.obj_hashfn		= nft_chain_hash_obj,
56 	.obj_cmpfn		= nft_chain_hash_cmp,
57 	.automatic_shrinking	= true,
58 };
59 
60 static const struct rhashtable_params nft_objname_ht_params = {
61 	.head_offset		= offsetof(struct nft_object, rhlhead),
62 	.key_offset		= offsetof(struct nft_object, key),
63 	.hashfn			= nft_objname_hash,
64 	.obj_hashfn		= nft_objname_hash_obj,
65 	.obj_cmpfn		= nft_objname_hash_cmp,
66 	.automatic_shrinking	= true,
67 };
68 
69 struct nft_audit_data {
70 	struct nft_table *table;
71 	int entries;
72 	int op;
73 	struct list_head list;
74 };
75 
76 static const u8 nft2audit_op[NFT_MSG_MAX] = { // enum nf_tables_msg_types
77 	[NFT_MSG_NEWTABLE]	= AUDIT_NFT_OP_TABLE_REGISTER,
78 	[NFT_MSG_GETTABLE]	= AUDIT_NFT_OP_INVALID,
79 	[NFT_MSG_DELTABLE]	= AUDIT_NFT_OP_TABLE_UNREGISTER,
80 	[NFT_MSG_NEWCHAIN]	= AUDIT_NFT_OP_CHAIN_REGISTER,
81 	[NFT_MSG_GETCHAIN]	= AUDIT_NFT_OP_INVALID,
82 	[NFT_MSG_DELCHAIN]	= AUDIT_NFT_OP_CHAIN_UNREGISTER,
83 	[NFT_MSG_NEWRULE]	= AUDIT_NFT_OP_RULE_REGISTER,
84 	[NFT_MSG_GETRULE]	= AUDIT_NFT_OP_INVALID,
85 	[NFT_MSG_DELRULE]	= AUDIT_NFT_OP_RULE_UNREGISTER,
86 	[NFT_MSG_NEWSET]	= AUDIT_NFT_OP_SET_REGISTER,
87 	[NFT_MSG_GETSET]	= AUDIT_NFT_OP_INVALID,
88 	[NFT_MSG_DELSET]	= AUDIT_NFT_OP_SET_UNREGISTER,
89 	[NFT_MSG_NEWSETELEM]	= AUDIT_NFT_OP_SETELEM_REGISTER,
90 	[NFT_MSG_GETSETELEM]	= AUDIT_NFT_OP_INVALID,
91 	[NFT_MSG_DELSETELEM]	= AUDIT_NFT_OP_SETELEM_UNREGISTER,
92 	[NFT_MSG_NEWGEN]	= AUDIT_NFT_OP_GEN_REGISTER,
93 	[NFT_MSG_GETGEN]	= AUDIT_NFT_OP_INVALID,
94 	[NFT_MSG_TRACE]		= AUDIT_NFT_OP_INVALID,
95 	[NFT_MSG_NEWOBJ]	= AUDIT_NFT_OP_OBJ_REGISTER,
96 	[NFT_MSG_GETOBJ]	= AUDIT_NFT_OP_INVALID,
97 	[NFT_MSG_DELOBJ]	= AUDIT_NFT_OP_OBJ_UNREGISTER,
98 	[NFT_MSG_GETOBJ_RESET]	= AUDIT_NFT_OP_OBJ_RESET,
99 	[NFT_MSG_NEWFLOWTABLE]	= AUDIT_NFT_OP_FLOWTABLE_REGISTER,
100 	[NFT_MSG_GETFLOWTABLE]	= AUDIT_NFT_OP_INVALID,
101 	[NFT_MSG_DELFLOWTABLE]	= AUDIT_NFT_OP_FLOWTABLE_UNREGISTER,
102 };
103 
nft_validate_state_update(struct net * net,u8 new_validate_state)104 static void nft_validate_state_update(struct net *net, u8 new_validate_state)
105 {
106 	switch (net->nft.validate_state) {
107 	case NFT_VALIDATE_SKIP:
108 		WARN_ON_ONCE(new_validate_state == NFT_VALIDATE_DO);
109 		break;
110 	case NFT_VALIDATE_NEED:
111 		break;
112 	case NFT_VALIDATE_DO:
113 		if (new_validate_state == NFT_VALIDATE_NEED)
114 			return;
115 	}
116 
117 	net->nft.validate_state = new_validate_state;
118 }
119 static void nf_tables_trans_destroy_work(struct work_struct *w);
120 static DECLARE_WORK(trans_destroy_work, nf_tables_trans_destroy_work);
121 
nft_ctx_init(struct nft_ctx * ctx,struct net * net,const struct sk_buff * skb,const struct nlmsghdr * nlh,u8 family,struct nft_table * table,struct nft_chain * chain,const struct nlattr * const * nla)122 static void nft_ctx_init(struct nft_ctx *ctx,
123 			 struct net *net,
124 			 const struct sk_buff *skb,
125 			 const struct nlmsghdr *nlh,
126 			 u8 family,
127 			 struct nft_table *table,
128 			 struct nft_chain *chain,
129 			 const struct nlattr * const *nla)
130 {
131 	ctx->net	= net;
132 	ctx->family	= family;
133 	ctx->level	= 0;
134 	ctx->table	= table;
135 	ctx->chain	= chain;
136 	ctx->nla   	= nla;
137 	ctx->portid	= NETLINK_CB(skb).portid;
138 	ctx->report	= nlmsg_report(nlh);
139 	ctx->flags	= nlh->nlmsg_flags;
140 	ctx->seq	= nlh->nlmsg_seq;
141 }
142 
nft_trans_alloc_gfp(const struct nft_ctx * ctx,int msg_type,u32 size,gfp_t gfp)143 static struct nft_trans *nft_trans_alloc_gfp(const struct nft_ctx *ctx,
144 					     int msg_type, u32 size, gfp_t gfp)
145 {
146 	struct nft_trans *trans;
147 
148 	trans = kzalloc(sizeof(struct nft_trans) + size, gfp);
149 	if (trans == NULL)
150 		return NULL;
151 
152 	INIT_LIST_HEAD(&trans->list);
153 	trans->msg_type = msg_type;
154 	trans->ctx	= *ctx;
155 
156 	return trans;
157 }
158 
nft_trans_alloc(const struct nft_ctx * ctx,int msg_type,u32 size)159 static struct nft_trans *nft_trans_alloc(const struct nft_ctx *ctx,
160 					 int msg_type, u32 size)
161 {
162 	return nft_trans_alloc_gfp(ctx, msg_type, size, GFP_KERNEL);
163 }
164 
nft_trans_destroy(struct nft_trans * trans)165 static void nft_trans_destroy(struct nft_trans *trans)
166 {
167 	list_del(&trans->list);
168 	kfree(trans);
169 }
170 
nft_set_trans_bind(const struct nft_ctx * ctx,struct nft_set * set)171 static void nft_set_trans_bind(const struct nft_ctx *ctx, struct nft_set *set)
172 {
173 	struct net *net = ctx->net;
174 	struct nft_trans *trans;
175 
176 	if (!nft_set_is_anonymous(set))
177 		return;
178 
179 	list_for_each_entry_reverse(trans, &net->nft.commit_list, list) {
180 		switch (trans->msg_type) {
181 		case NFT_MSG_NEWSET:
182 			if (nft_trans_set(trans) == set)
183 				nft_trans_set_bound(trans) = true;
184 			break;
185 		case NFT_MSG_NEWSETELEM:
186 			if (nft_trans_elem_set(trans) == set)
187 				nft_trans_elem_set_bound(trans) = true;
188 			break;
189 		}
190 	}
191 }
192 
nft_netdev_register_hooks(struct net * net,struct list_head * hook_list)193 static int nft_netdev_register_hooks(struct net *net,
194 				     struct list_head *hook_list)
195 {
196 	struct nft_hook *hook;
197 	int err, j;
198 
199 	j = 0;
200 	list_for_each_entry(hook, hook_list, list) {
201 		err = nf_register_net_hook(net, &hook->ops);
202 		if (err < 0)
203 			goto err_register;
204 
205 		j++;
206 	}
207 	return 0;
208 
209 err_register:
210 	list_for_each_entry(hook, hook_list, list) {
211 		if (j-- <= 0)
212 			break;
213 
214 		nf_unregister_net_hook(net, &hook->ops);
215 	}
216 	return err;
217 }
218 
nft_netdev_unregister_hooks(struct net * net,struct list_head * hook_list)219 static void nft_netdev_unregister_hooks(struct net *net,
220 					struct list_head *hook_list)
221 {
222 	struct nft_hook *hook;
223 
224 	list_for_each_entry(hook, hook_list, list)
225 		nf_unregister_net_hook(net, &hook->ops);
226 }
227 
nf_tables_register_hook(struct net * net,const struct nft_table * table,struct nft_chain * chain)228 static int nf_tables_register_hook(struct net *net,
229 				   const struct nft_table *table,
230 				   struct nft_chain *chain)
231 {
232 	struct nft_base_chain *basechain;
233 	const struct nf_hook_ops *ops;
234 
235 	if (table->flags & NFT_TABLE_F_DORMANT ||
236 	    !nft_is_base_chain(chain))
237 		return 0;
238 
239 	basechain = nft_base_chain(chain);
240 	ops = &basechain->ops;
241 
242 	if (basechain->type->ops_register)
243 		return basechain->type->ops_register(net, ops);
244 
245 	if (nft_base_chain_netdev(table->family, basechain->ops.hooknum))
246 		return nft_netdev_register_hooks(net, &basechain->hook_list);
247 
248 	return nf_register_net_hook(net, &basechain->ops);
249 }
250 
nf_tables_unregister_hook(struct net * net,const struct nft_table * table,struct nft_chain * chain)251 static void nf_tables_unregister_hook(struct net *net,
252 				      const struct nft_table *table,
253 				      struct nft_chain *chain)
254 {
255 	struct nft_base_chain *basechain;
256 	const struct nf_hook_ops *ops;
257 
258 	if (table->flags & NFT_TABLE_F_DORMANT ||
259 	    !nft_is_base_chain(chain))
260 		return;
261 	basechain = nft_base_chain(chain);
262 	ops = &basechain->ops;
263 
264 	if (basechain->type->ops_unregister)
265 		return basechain->type->ops_unregister(net, ops);
266 
267 	if (nft_base_chain_netdev(table->family, basechain->ops.hooknum))
268 		nft_netdev_unregister_hooks(net, &basechain->hook_list);
269 	else
270 		nf_unregister_net_hook(net, &basechain->ops);
271 }
272 
nft_trans_table_add(struct nft_ctx * ctx,int msg_type)273 static int nft_trans_table_add(struct nft_ctx *ctx, int msg_type)
274 {
275 	struct nft_trans *trans;
276 
277 	trans = nft_trans_alloc(ctx, msg_type, sizeof(struct nft_trans_table));
278 	if (trans == NULL)
279 		return -ENOMEM;
280 
281 	if (msg_type == NFT_MSG_NEWTABLE)
282 		nft_activate_next(ctx->net, ctx->table);
283 
284 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
285 	return 0;
286 }
287 
nft_deltable(struct nft_ctx * ctx)288 static int nft_deltable(struct nft_ctx *ctx)
289 {
290 	int err;
291 
292 	err = nft_trans_table_add(ctx, NFT_MSG_DELTABLE);
293 	if (err < 0)
294 		return err;
295 
296 	nft_deactivate_next(ctx->net, ctx->table);
297 	return err;
298 }
299 
nft_trans_chain_add(struct nft_ctx * ctx,int msg_type)300 static struct nft_trans *nft_trans_chain_add(struct nft_ctx *ctx, int msg_type)
301 {
302 	struct nft_trans *trans;
303 
304 	trans = nft_trans_alloc(ctx, msg_type, sizeof(struct nft_trans_chain));
305 	if (trans == NULL)
306 		return ERR_PTR(-ENOMEM);
307 
308 	if (msg_type == NFT_MSG_NEWCHAIN) {
309 		nft_activate_next(ctx->net, ctx->chain);
310 
311 		if (ctx->nla[NFTA_CHAIN_ID]) {
312 			nft_trans_chain_id(trans) =
313 				ntohl(nla_get_be32(ctx->nla[NFTA_CHAIN_ID]));
314 		}
315 	}
316 
317 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
318 	return trans;
319 }
320 
nft_delchain(struct nft_ctx * ctx)321 static int nft_delchain(struct nft_ctx *ctx)
322 {
323 	struct nft_trans *trans;
324 
325 	trans = nft_trans_chain_add(ctx, NFT_MSG_DELCHAIN);
326 	if (IS_ERR(trans))
327 		return PTR_ERR(trans);
328 
329 	ctx->table->use--;
330 	nft_deactivate_next(ctx->net, ctx->chain);
331 
332 	return 0;
333 }
334 
nft_rule_expr_activate(const struct nft_ctx * ctx,struct nft_rule * rule)335 static void nft_rule_expr_activate(const struct nft_ctx *ctx,
336 				   struct nft_rule *rule)
337 {
338 	struct nft_expr *expr;
339 
340 	expr = nft_expr_first(rule);
341 	while (nft_expr_more(rule, expr)) {
342 		if (expr->ops->activate)
343 			expr->ops->activate(ctx, expr);
344 
345 		expr = nft_expr_next(expr);
346 	}
347 }
348 
nft_rule_expr_deactivate(const struct nft_ctx * ctx,struct nft_rule * rule,enum nft_trans_phase phase)349 static void nft_rule_expr_deactivate(const struct nft_ctx *ctx,
350 				     struct nft_rule *rule,
351 				     enum nft_trans_phase phase)
352 {
353 	struct nft_expr *expr;
354 
355 	expr = nft_expr_first(rule);
356 	while (nft_expr_more(rule, expr)) {
357 		if (expr->ops->deactivate)
358 			expr->ops->deactivate(ctx, expr, phase);
359 
360 		expr = nft_expr_next(expr);
361 	}
362 }
363 
364 static int
nf_tables_delrule_deactivate(struct nft_ctx * ctx,struct nft_rule * rule)365 nf_tables_delrule_deactivate(struct nft_ctx *ctx, struct nft_rule *rule)
366 {
367 	/* You cannot delete the same rule twice */
368 	if (nft_is_active_next(ctx->net, rule)) {
369 		nft_deactivate_next(ctx->net, rule);
370 		ctx->chain->use--;
371 		return 0;
372 	}
373 	return -ENOENT;
374 }
375 
nft_trans_rule_add(struct nft_ctx * ctx,int msg_type,struct nft_rule * rule)376 static struct nft_trans *nft_trans_rule_add(struct nft_ctx *ctx, int msg_type,
377 					    struct nft_rule *rule)
378 {
379 	struct nft_trans *trans;
380 
381 	trans = nft_trans_alloc(ctx, msg_type, sizeof(struct nft_trans_rule));
382 	if (trans == NULL)
383 		return NULL;
384 
385 	if (msg_type == NFT_MSG_NEWRULE && ctx->nla[NFTA_RULE_ID] != NULL) {
386 		nft_trans_rule_id(trans) =
387 			ntohl(nla_get_be32(ctx->nla[NFTA_RULE_ID]));
388 	}
389 	nft_trans_rule(trans) = rule;
390 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
391 
392 	return trans;
393 }
394 
nft_delrule(struct nft_ctx * ctx,struct nft_rule * rule)395 static int nft_delrule(struct nft_ctx *ctx, struct nft_rule *rule)
396 {
397 	struct nft_flow_rule *flow;
398 	struct nft_trans *trans;
399 	int err;
400 
401 	trans = nft_trans_rule_add(ctx, NFT_MSG_DELRULE, rule);
402 	if (trans == NULL)
403 		return -ENOMEM;
404 
405 	if (ctx->chain->flags & NFT_CHAIN_HW_OFFLOAD) {
406 		flow = nft_flow_rule_create(ctx->net, rule);
407 		if (IS_ERR(flow)) {
408 			nft_trans_destroy(trans);
409 			return PTR_ERR(flow);
410 		}
411 
412 		nft_trans_flow_rule(trans) = flow;
413 	}
414 
415 	err = nf_tables_delrule_deactivate(ctx, rule);
416 	if (err < 0) {
417 		nft_trans_destroy(trans);
418 		return err;
419 	}
420 	nft_rule_expr_deactivate(ctx, rule, NFT_TRANS_PREPARE);
421 
422 	return 0;
423 }
424 
nft_delrule_by_chain(struct nft_ctx * ctx)425 static int nft_delrule_by_chain(struct nft_ctx *ctx)
426 {
427 	struct nft_rule *rule;
428 	int err;
429 
430 	list_for_each_entry(rule, &ctx->chain->rules, list) {
431 		if (!nft_is_active_next(ctx->net, rule))
432 			continue;
433 
434 		err = nft_delrule(ctx, rule);
435 		if (err < 0)
436 			return err;
437 	}
438 	return 0;
439 }
440 
nft_trans_set_add(const struct nft_ctx * ctx,int msg_type,struct nft_set * set)441 static int nft_trans_set_add(const struct nft_ctx *ctx, int msg_type,
442 			     struct nft_set *set)
443 {
444 	struct nft_trans *trans;
445 
446 	trans = nft_trans_alloc(ctx, msg_type, sizeof(struct nft_trans_set));
447 	if (trans == NULL)
448 		return -ENOMEM;
449 
450 	if (msg_type == NFT_MSG_NEWSET && ctx->nla[NFTA_SET_ID] != NULL) {
451 		nft_trans_set_id(trans) =
452 			ntohl(nla_get_be32(ctx->nla[NFTA_SET_ID]));
453 		nft_activate_next(ctx->net, set);
454 	}
455 	nft_trans_set(trans) = set;
456 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
457 
458 	return 0;
459 }
460 
nft_delset(const struct nft_ctx * ctx,struct nft_set * set)461 static int nft_delset(const struct nft_ctx *ctx, struct nft_set *set)
462 {
463 	int err;
464 
465 	err = nft_trans_set_add(ctx, NFT_MSG_DELSET, set);
466 	if (err < 0)
467 		return err;
468 
469 	nft_deactivate_next(ctx->net, set);
470 	ctx->table->use--;
471 
472 	return err;
473 }
474 
nft_trans_obj_add(struct nft_ctx * ctx,int msg_type,struct nft_object * obj)475 static int nft_trans_obj_add(struct nft_ctx *ctx, int msg_type,
476 			     struct nft_object *obj)
477 {
478 	struct nft_trans *trans;
479 
480 	trans = nft_trans_alloc(ctx, msg_type, sizeof(struct nft_trans_obj));
481 	if (trans == NULL)
482 		return -ENOMEM;
483 
484 	if (msg_type == NFT_MSG_NEWOBJ)
485 		nft_activate_next(ctx->net, obj);
486 
487 	nft_trans_obj(trans) = obj;
488 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
489 
490 	return 0;
491 }
492 
nft_delobj(struct nft_ctx * ctx,struct nft_object * obj)493 static int nft_delobj(struct nft_ctx *ctx, struct nft_object *obj)
494 {
495 	int err;
496 
497 	err = nft_trans_obj_add(ctx, NFT_MSG_DELOBJ, obj);
498 	if (err < 0)
499 		return err;
500 
501 	nft_deactivate_next(ctx->net, obj);
502 	ctx->table->use--;
503 
504 	return err;
505 }
506 
nft_trans_flowtable_add(struct nft_ctx * ctx,int msg_type,struct nft_flowtable * flowtable)507 static int nft_trans_flowtable_add(struct nft_ctx *ctx, int msg_type,
508 				   struct nft_flowtable *flowtable)
509 {
510 	struct nft_trans *trans;
511 
512 	trans = nft_trans_alloc(ctx, msg_type,
513 				sizeof(struct nft_trans_flowtable));
514 	if (trans == NULL)
515 		return -ENOMEM;
516 
517 	if (msg_type == NFT_MSG_NEWFLOWTABLE)
518 		nft_activate_next(ctx->net, flowtable);
519 
520 	INIT_LIST_HEAD(&nft_trans_flowtable_hooks(trans));
521 	nft_trans_flowtable(trans) = flowtable;
522 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
523 
524 	return 0;
525 }
526 
nft_delflowtable(struct nft_ctx * ctx,struct nft_flowtable * flowtable)527 static int nft_delflowtable(struct nft_ctx *ctx,
528 			    struct nft_flowtable *flowtable)
529 {
530 	int err;
531 
532 	err = nft_trans_flowtable_add(ctx, NFT_MSG_DELFLOWTABLE, flowtable);
533 	if (err < 0)
534 		return err;
535 
536 	nft_deactivate_next(ctx->net, flowtable);
537 	ctx->table->use--;
538 
539 	return err;
540 }
541 
542 /*
543  * Tables
544  */
545 
nft_table_lookup(const struct net * net,const struct nlattr * nla,u8 family,u8 genmask)546 static struct nft_table *nft_table_lookup(const struct net *net,
547 					  const struct nlattr *nla,
548 					  u8 family, u8 genmask)
549 {
550 	struct nft_table *table;
551 
552 	if (nla == NULL)
553 		return ERR_PTR(-EINVAL);
554 
555 	list_for_each_entry_rcu(table, &net->nft.tables, list,
556 				lockdep_is_held(&net->nft.commit_mutex)) {
557 		if (!nla_strcmp(nla, table->name) &&
558 		    table->family == family &&
559 		    nft_active_genmask(table, genmask))
560 			return table;
561 	}
562 
563 	return ERR_PTR(-ENOENT);
564 }
565 
nft_table_lookup_byhandle(const struct net * net,const struct nlattr * nla,u8 genmask)566 static struct nft_table *nft_table_lookup_byhandle(const struct net *net,
567 						   const struct nlattr *nla,
568 						   u8 genmask)
569 {
570 	struct nft_table *table;
571 
572 	list_for_each_entry(table, &net->nft.tables, list) {
573 		if (be64_to_cpu(nla_get_be64(nla)) == table->handle &&
574 		    nft_active_genmask(table, genmask))
575 			return table;
576 	}
577 
578 	return ERR_PTR(-ENOENT);
579 }
580 
nf_tables_alloc_handle(struct nft_table * table)581 static inline u64 nf_tables_alloc_handle(struct nft_table *table)
582 {
583 	return ++table->hgenerator;
584 }
585 
586 static const struct nft_chain_type *chain_type[NFPROTO_NUMPROTO][NFT_CHAIN_T_MAX];
587 
588 static const struct nft_chain_type *
__nft_chain_type_get(u8 family,enum nft_chain_types type)589 __nft_chain_type_get(u8 family, enum nft_chain_types type)
590 {
591 	if (family >= NFPROTO_NUMPROTO ||
592 	    type >= NFT_CHAIN_T_MAX)
593 		return NULL;
594 
595 	return chain_type[family][type];
596 }
597 
598 static const struct nft_chain_type *
__nf_tables_chain_type_lookup(const struct nlattr * nla,u8 family)599 __nf_tables_chain_type_lookup(const struct nlattr *nla, u8 family)
600 {
601 	const struct nft_chain_type *type;
602 	int i;
603 
604 	for (i = 0; i < NFT_CHAIN_T_MAX; i++) {
605 		type = __nft_chain_type_get(family, i);
606 		if (!type)
607 			continue;
608 		if (!nla_strcmp(nla, type->name))
609 			return type;
610 	}
611 	return NULL;
612 }
613 
614 struct nft_module_request {
615 	struct list_head	list;
616 	char			module[MODULE_NAME_LEN];
617 	bool			done;
618 };
619 
620 #ifdef CONFIG_MODULES
nft_request_module(struct net * net,const char * fmt,...)621 static int nft_request_module(struct net *net, const char *fmt, ...)
622 {
623 	char module_name[MODULE_NAME_LEN];
624 	struct nft_module_request *req;
625 	va_list args;
626 	int ret;
627 
628 	va_start(args, fmt);
629 	ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
630 	va_end(args);
631 	if (ret >= MODULE_NAME_LEN)
632 		return 0;
633 
634 	list_for_each_entry(req, &net->nft.module_list, list) {
635 		if (!strcmp(req->module, module_name)) {
636 			if (req->done)
637 				return 0;
638 
639 			/* A request to load this module already exists. */
640 			return -EAGAIN;
641 		}
642 	}
643 
644 	req = kmalloc(sizeof(*req), GFP_KERNEL);
645 	if (!req)
646 		return -ENOMEM;
647 
648 	req->done = false;
649 	strlcpy(req->module, module_name, MODULE_NAME_LEN);
650 	list_add_tail(&req->list, &net->nft.module_list);
651 
652 	return -EAGAIN;
653 }
654 #endif
655 
lockdep_nfnl_nft_mutex_not_held(void)656 static void lockdep_nfnl_nft_mutex_not_held(void)
657 {
658 #ifdef CONFIG_PROVE_LOCKING
659 	if (debug_locks)
660 		WARN_ON_ONCE(lockdep_nfnl_is_held(NFNL_SUBSYS_NFTABLES));
661 #endif
662 }
663 
664 static const struct nft_chain_type *
nf_tables_chain_type_lookup(struct net * net,const struct nlattr * nla,u8 family,bool autoload)665 nf_tables_chain_type_lookup(struct net *net, const struct nlattr *nla,
666 			    u8 family, bool autoload)
667 {
668 	const struct nft_chain_type *type;
669 
670 	type = __nf_tables_chain_type_lookup(nla, family);
671 	if (type != NULL)
672 		return type;
673 
674 	lockdep_nfnl_nft_mutex_not_held();
675 #ifdef CONFIG_MODULES
676 	if (autoload) {
677 		if (nft_request_module(net, "nft-chain-%u-%.*s", family,
678 				       nla_len(nla),
679 				       (const char *)nla_data(nla)) == -EAGAIN)
680 			return ERR_PTR(-EAGAIN);
681 	}
682 #endif
683 	return ERR_PTR(-ENOENT);
684 }
685 
nft_base_seq(const struct net * net)686 static __be16 nft_base_seq(const struct net *net)
687 {
688 	return htons(net->nft.base_seq & 0xffff);
689 }
690 
691 static const struct nla_policy nft_table_policy[NFTA_TABLE_MAX + 1] = {
692 	[NFTA_TABLE_NAME]	= { .type = NLA_STRING,
693 				    .len = NFT_TABLE_MAXNAMELEN - 1 },
694 	[NFTA_TABLE_FLAGS]	= { .type = NLA_U32 },
695 	[NFTA_TABLE_HANDLE]	= { .type = NLA_U64 },
696 	[NFTA_TABLE_USERDATA]	= { .type = NLA_BINARY,
697 				    .len = NFT_USERDATA_MAXLEN }
698 };
699 
nf_tables_fill_table_info(struct sk_buff * skb,struct net * net,u32 portid,u32 seq,int event,u32 flags,int family,const struct nft_table * table)700 static int nf_tables_fill_table_info(struct sk_buff *skb, struct net *net,
701 				     u32 portid, u32 seq, int event, u32 flags,
702 				     int family, const struct nft_table *table)
703 {
704 	struct nlmsghdr *nlh;
705 
706 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
707 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
708 			   NFNETLINK_V0, nft_base_seq(net));
709 	if (!nlh)
710 		goto nla_put_failure;
711 
712 	if (nla_put_string(skb, NFTA_TABLE_NAME, table->name) ||
713 	    nla_put_be32(skb, NFTA_TABLE_FLAGS, htonl(table->flags)) ||
714 	    nla_put_be32(skb, NFTA_TABLE_USE, htonl(table->use)) ||
715 	    nla_put_be64(skb, NFTA_TABLE_HANDLE, cpu_to_be64(table->handle),
716 			 NFTA_TABLE_PAD))
717 		goto nla_put_failure;
718 
719 	if (table->udata) {
720 		if (nla_put(skb, NFTA_TABLE_USERDATA, table->udlen, table->udata))
721 			goto nla_put_failure;
722 	}
723 
724 	nlmsg_end(skb, nlh);
725 	return 0;
726 
727 nla_put_failure:
728 	nlmsg_trim(skb, nlh);
729 	return -1;
730 }
731 
732 struct nftnl_skb_parms {
733 	bool report;
734 };
735 #define NFT_CB(skb)	(*(struct nftnl_skb_parms*)&((skb)->cb))
736 
nft_notify_enqueue(struct sk_buff * skb,bool report,struct list_head * notify_list)737 static void nft_notify_enqueue(struct sk_buff *skb, bool report,
738 			       struct list_head *notify_list)
739 {
740 	NFT_CB(skb).report = report;
741 	list_add_tail(&skb->list, notify_list);
742 }
743 
nf_tables_table_notify(const struct nft_ctx * ctx,int event)744 static void nf_tables_table_notify(const struct nft_ctx *ctx, int event)
745 {
746 	struct sk_buff *skb;
747 	int err;
748 
749 	if (!ctx->report &&
750 	    !nfnetlink_has_listeners(ctx->net, NFNLGRP_NFTABLES))
751 		return;
752 
753 	skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
754 	if (skb == NULL)
755 		goto err;
756 
757 	err = nf_tables_fill_table_info(skb, ctx->net, ctx->portid, ctx->seq,
758 					event, 0, ctx->family, ctx->table);
759 	if (err < 0) {
760 		kfree_skb(skb);
761 		goto err;
762 	}
763 
764 	nft_notify_enqueue(skb, ctx->report, &ctx->net->nft.notify_list);
765 	return;
766 err:
767 	nfnetlink_set_err(ctx->net, ctx->portid, NFNLGRP_NFTABLES, -ENOBUFS);
768 }
769 
nf_tables_dump_tables(struct sk_buff * skb,struct netlink_callback * cb)770 static int nf_tables_dump_tables(struct sk_buff *skb,
771 				 struct netlink_callback *cb)
772 {
773 	const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
774 	const struct nft_table *table;
775 	unsigned int idx = 0, s_idx = cb->args[0];
776 	struct net *net = sock_net(skb->sk);
777 	int family = nfmsg->nfgen_family;
778 
779 	rcu_read_lock();
780 	cb->seq = net->nft.base_seq;
781 
782 	list_for_each_entry_rcu(table, &net->nft.tables, list) {
783 		if (family != NFPROTO_UNSPEC && family != table->family)
784 			continue;
785 
786 		if (idx < s_idx)
787 			goto cont;
788 		if (idx > s_idx)
789 			memset(&cb->args[1], 0,
790 			       sizeof(cb->args) - sizeof(cb->args[0]));
791 		if (!nft_is_active(net, table))
792 			continue;
793 		if (nf_tables_fill_table_info(skb, net,
794 					      NETLINK_CB(cb->skb).portid,
795 					      cb->nlh->nlmsg_seq,
796 					      NFT_MSG_NEWTABLE, NLM_F_MULTI,
797 					      table->family, table) < 0)
798 			goto done;
799 
800 		nl_dump_check_consistent(cb, nlmsg_hdr(skb));
801 cont:
802 		idx++;
803 	}
804 done:
805 	rcu_read_unlock();
806 	cb->args[0] = idx;
807 	return skb->len;
808 }
809 
nft_netlink_dump_start_rcu(struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,struct netlink_dump_control * c)810 static int nft_netlink_dump_start_rcu(struct sock *nlsk, struct sk_buff *skb,
811 				      const struct nlmsghdr *nlh,
812 				      struct netlink_dump_control *c)
813 {
814 	int err;
815 
816 	if (!try_module_get(THIS_MODULE))
817 		return -EINVAL;
818 
819 	rcu_read_unlock();
820 	err = netlink_dump_start(nlsk, skb, nlh, c);
821 	rcu_read_lock();
822 	module_put(THIS_MODULE);
823 
824 	return err;
825 }
826 
827 /* called with rcu_read_lock held */
nf_tables_gettable(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)828 static int nf_tables_gettable(struct net *net, struct sock *nlsk,
829 			      struct sk_buff *skb, const struct nlmsghdr *nlh,
830 			      const struct nlattr * const nla[],
831 			      struct netlink_ext_ack *extack)
832 {
833 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
834 	u8 genmask = nft_genmask_cur(net);
835 	const struct nft_table *table;
836 	struct sk_buff *skb2;
837 	int family = nfmsg->nfgen_family;
838 	int err;
839 
840 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
841 		struct netlink_dump_control c = {
842 			.dump = nf_tables_dump_tables,
843 			.module = THIS_MODULE,
844 		};
845 
846 		return nft_netlink_dump_start_rcu(nlsk, skb, nlh, &c);
847 	}
848 
849 	table = nft_table_lookup(net, nla[NFTA_TABLE_NAME], family, genmask);
850 	if (IS_ERR(table)) {
851 		NL_SET_BAD_ATTR(extack, nla[NFTA_TABLE_NAME]);
852 		return PTR_ERR(table);
853 	}
854 
855 	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
856 	if (!skb2)
857 		return -ENOMEM;
858 
859 	err = nf_tables_fill_table_info(skb2, net, NETLINK_CB(skb).portid,
860 					nlh->nlmsg_seq, NFT_MSG_NEWTABLE, 0,
861 					family, table);
862 	if (err < 0)
863 		goto err_fill_table_info;
864 
865 	return nfnetlink_unicast(skb2, net, NETLINK_CB(skb).portid);
866 
867 err_fill_table_info:
868 	kfree_skb(skb2);
869 	return err;
870 }
871 
nft_table_disable(struct net * net,struct nft_table * table,u32 cnt)872 static void nft_table_disable(struct net *net, struct nft_table *table, u32 cnt)
873 {
874 	struct nft_chain *chain;
875 	u32 i = 0;
876 
877 	list_for_each_entry(chain, &table->chains, list) {
878 		if (!nft_is_active_next(net, chain))
879 			continue;
880 		if (!nft_is_base_chain(chain))
881 			continue;
882 
883 		if (cnt && i++ == cnt)
884 			break;
885 
886 		nf_tables_unregister_hook(net, table, chain);
887 	}
888 }
889 
nf_tables_table_enable(struct net * net,struct nft_table * table)890 static int nf_tables_table_enable(struct net *net, struct nft_table *table)
891 {
892 	struct nft_chain *chain;
893 	int err, i = 0;
894 
895 	list_for_each_entry(chain, &table->chains, list) {
896 		if (!nft_is_active_next(net, chain))
897 			continue;
898 		if (!nft_is_base_chain(chain))
899 			continue;
900 
901 		err = nf_tables_register_hook(net, table, chain);
902 		if (err < 0)
903 			goto err_register_hooks;
904 
905 		i++;
906 	}
907 	return 0;
908 
909 err_register_hooks:
910 	if (i)
911 		nft_table_disable(net, table, i);
912 	return err;
913 }
914 
nf_tables_table_disable(struct net * net,struct nft_table * table)915 static void nf_tables_table_disable(struct net *net, struct nft_table *table)
916 {
917 	nft_table_disable(net, table, 0);
918 }
919 
nf_tables_updtable(struct nft_ctx * ctx)920 static int nf_tables_updtable(struct nft_ctx *ctx)
921 {
922 	struct nft_trans *trans;
923 	u32 flags;
924 	int ret = 0;
925 
926 	if (!ctx->nla[NFTA_TABLE_FLAGS])
927 		return 0;
928 
929 	flags = ntohl(nla_get_be32(ctx->nla[NFTA_TABLE_FLAGS]));
930 	if (flags & ~NFT_TABLE_F_DORMANT)
931 		return -EINVAL;
932 
933 	if (flags == ctx->table->flags)
934 		return 0;
935 
936 	trans = nft_trans_alloc(ctx, NFT_MSG_NEWTABLE,
937 				sizeof(struct nft_trans_table));
938 	if (trans == NULL)
939 		return -ENOMEM;
940 
941 	if ((flags & NFT_TABLE_F_DORMANT) &&
942 	    !(ctx->table->flags & NFT_TABLE_F_DORMANT)) {
943 		nft_trans_table_enable(trans) = false;
944 	} else if (!(flags & NFT_TABLE_F_DORMANT) &&
945 		   ctx->table->flags & NFT_TABLE_F_DORMANT) {
946 		ctx->table->flags &= ~NFT_TABLE_F_DORMANT;
947 		ret = nf_tables_table_enable(ctx->net, ctx->table);
948 		if (ret >= 0)
949 			nft_trans_table_enable(trans) = true;
950 		else
951 			ctx->table->flags |= NFT_TABLE_F_DORMANT;
952 	}
953 	if (ret < 0)
954 		goto err;
955 
956 	nft_trans_table_update(trans) = true;
957 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
958 	return 0;
959 err:
960 	nft_trans_destroy(trans);
961 	return ret;
962 }
963 
nft_chain_hash(const void * data,u32 len,u32 seed)964 static u32 nft_chain_hash(const void *data, u32 len, u32 seed)
965 {
966 	const char *name = data;
967 
968 	return jhash(name, strlen(name), seed);
969 }
970 
nft_chain_hash_obj(const void * data,u32 len,u32 seed)971 static u32 nft_chain_hash_obj(const void *data, u32 len, u32 seed)
972 {
973 	const struct nft_chain *chain = data;
974 
975 	return nft_chain_hash(chain->name, 0, seed);
976 }
977 
nft_chain_hash_cmp(struct rhashtable_compare_arg * arg,const void * ptr)978 static int nft_chain_hash_cmp(struct rhashtable_compare_arg *arg,
979 			      const void *ptr)
980 {
981 	const struct nft_chain *chain = ptr;
982 	const char *name = arg->key;
983 
984 	return strcmp(chain->name, name);
985 }
986 
nft_objname_hash(const void * data,u32 len,u32 seed)987 static u32 nft_objname_hash(const void *data, u32 len, u32 seed)
988 {
989 	const struct nft_object_hash_key *k = data;
990 
991 	seed ^= hash_ptr(k->table, 32);
992 
993 	return jhash(k->name, strlen(k->name), seed);
994 }
995 
nft_objname_hash_obj(const void * data,u32 len,u32 seed)996 static u32 nft_objname_hash_obj(const void *data, u32 len, u32 seed)
997 {
998 	const struct nft_object *obj = data;
999 
1000 	return nft_objname_hash(&obj->key, 0, seed);
1001 }
1002 
nft_objname_hash_cmp(struct rhashtable_compare_arg * arg,const void * ptr)1003 static int nft_objname_hash_cmp(struct rhashtable_compare_arg *arg,
1004 				const void *ptr)
1005 {
1006 	const struct nft_object_hash_key *k = arg->key;
1007 	const struct nft_object *obj = ptr;
1008 
1009 	if (obj->key.table != k->table)
1010 		return -1;
1011 
1012 	return strcmp(obj->key.name, k->name);
1013 }
1014 
nf_tables_newtable(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)1015 static int nf_tables_newtable(struct net *net, struct sock *nlsk,
1016 			      struct sk_buff *skb, const struct nlmsghdr *nlh,
1017 			      const struct nlattr * const nla[],
1018 			      struct netlink_ext_ack *extack)
1019 {
1020 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1021 	u8 genmask = nft_genmask_next(net);
1022 	int family = nfmsg->nfgen_family;
1023 	const struct nlattr *attr;
1024 	struct nft_table *table;
1025 	struct nft_ctx ctx;
1026 	u32 flags = 0;
1027 	int err;
1028 
1029 	lockdep_assert_held(&net->nft.commit_mutex);
1030 	attr = nla[NFTA_TABLE_NAME];
1031 	table = nft_table_lookup(net, attr, family, genmask);
1032 	if (IS_ERR(table)) {
1033 		if (PTR_ERR(table) != -ENOENT)
1034 			return PTR_ERR(table);
1035 	} else {
1036 		if (nlh->nlmsg_flags & NLM_F_EXCL) {
1037 			NL_SET_BAD_ATTR(extack, attr);
1038 			return -EEXIST;
1039 		}
1040 		if (nlh->nlmsg_flags & NLM_F_REPLACE)
1041 			return -EOPNOTSUPP;
1042 
1043 		nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
1044 		return nf_tables_updtable(&ctx);
1045 	}
1046 
1047 	if (nla[NFTA_TABLE_FLAGS]) {
1048 		flags = ntohl(nla_get_be32(nla[NFTA_TABLE_FLAGS]));
1049 		if (flags & ~NFT_TABLE_F_DORMANT)
1050 			return -EINVAL;
1051 	}
1052 
1053 	err = -ENOMEM;
1054 	table = kzalloc(sizeof(*table), GFP_KERNEL);
1055 	if (table == NULL)
1056 		goto err_kzalloc;
1057 
1058 	table->name = nla_strdup(attr, GFP_KERNEL);
1059 	if (table->name == NULL)
1060 		goto err_strdup;
1061 
1062 	if (nla[NFTA_TABLE_USERDATA]) {
1063 		table->udata = nla_memdup(nla[NFTA_TABLE_USERDATA], GFP_KERNEL);
1064 		if (table->udata == NULL)
1065 			goto err_table_udata;
1066 
1067 		table->udlen = nla_len(nla[NFTA_TABLE_USERDATA]);
1068 	}
1069 
1070 	err = rhltable_init(&table->chains_ht, &nft_chain_ht_params);
1071 	if (err)
1072 		goto err_chain_ht;
1073 
1074 	INIT_LIST_HEAD(&table->chains);
1075 	INIT_LIST_HEAD(&table->sets);
1076 	INIT_LIST_HEAD(&table->objects);
1077 	INIT_LIST_HEAD(&table->flowtables);
1078 	table->family = family;
1079 	table->flags = flags;
1080 	table->handle = ++table_handle;
1081 
1082 	nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
1083 	err = nft_trans_table_add(&ctx, NFT_MSG_NEWTABLE);
1084 	if (err < 0)
1085 		goto err_trans;
1086 
1087 	list_add_tail_rcu(&table->list, &net->nft.tables);
1088 	return 0;
1089 err_trans:
1090 	rhltable_destroy(&table->chains_ht);
1091 err_chain_ht:
1092 	kfree(table->udata);
1093 err_table_udata:
1094 	kfree(table->name);
1095 err_strdup:
1096 	kfree(table);
1097 err_kzalloc:
1098 	return err;
1099 }
1100 
nft_flush_table(struct nft_ctx * ctx)1101 static int nft_flush_table(struct nft_ctx *ctx)
1102 {
1103 	struct nft_flowtable *flowtable, *nft;
1104 	struct nft_chain *chain, *nc;
1105 	struct nft_object *obj, *ne;
1106 	struct nft_set *set, *ns;
1107 	int err;
1108 
1109 	list_for_each_entry(chain, &ctx->table->chains, list) {
1110 		if (!nft_is_active_next(ctx->net, chain))
1111 			continue;
1112 
1113 		if (nft_chain_is_bound(chain))
1114 			continue;
1115 
1116 		ctx->chain = chain;
1117 
1118 		err = nft_delrule_by_chain(ctx);
1119 		if (err < 0)
1120 			goto out;
1121 	}
1122 
1123 	list_for_each_entry_safe(set, ns, &ctx->table->sets, list) {
1124 		if (!nft_is_active_next(ctx->net, set))
1125 			continue;
1126 
1127 		if (nft_set_is_anonymous(set) &&
1128 		    !list_empty(&set->bindings))
1129 			continue;
1130 
1131 		err = nft_delset(ctx, set);
1132 		if (err < 0)
1133 			goto out;
1134 	}
1135 
1136 	list_for_each_entry_safe(flowtable, nft, &ctx->table->flowtables, list) {
1137 		if (!nft_is_active_next(ctx->net, flowtable))
1138 			continue;
1139 
1140 		err = nft_delflowtable(ctx, flowtable);
1141 		if (err < 0)
1142 			goto out;
1143 	}
1144 
1145 	list_for_each_entry_safe(obj, ne, &ctx->table->objects, list) {
1146 		if (!nft_is_active_next(ctx->net, obj))
1147 			continue;
1148 
1149 		err = nft_delobj(ctx, obj);
1150 		if (err < 0)
1151 			goto out;
1152 	}
1153 
1154 	list_for_each_entry_safe(chain, nc, &ctx->table->chains, list) {
1155 		if (!nft_is_active_next(ctx->net, chain))
1156 			continue;
1157 
1158 		if (nft_chain_is_bound(chain))
1159 			continue;
1160 
1161 		ctx->chain = chain;
1162 
1163 		err = nft_delchain(ctx);
1164 		if (err < 0)
1165 			goto out;
1166 	}
1167 
1168 	err = nft_deltable(ctx);
1169 out:
1170 	return err;
1171 }
1172 
nft_flush(struct nft_ctx * ctx,int family)1173 static int nft_flush(struct nft_ctx *ctx, int family)
1174 {
1175 	struct nft_table *table, *nt;
1176 	const struct nlattr * const *nla = ctx->nla;
1177 	int err = 0;
1178 
1179 	list_for_each_entry_safe(table, nt, &ctx->net->nft.tables, list) {
1180 		if (family != AF_UNSPEC && table->family != family)
1181 			continue;
1182 
1183 		ctx->family = table->family;
1184 
1185 		if (!nft_is_active_next(ctx->net, table))
1186 			continue;
1187 
1188 		if (nla[NFTA_TABLE_NAME] &&
1189 		    nla_strcmp(nla[NFTA_TABLE_NAME], table->name) != 0)
1190 			continue;
1191 
1192 		ctx->table = table;
1193 
1194 		err = nft_flush_table(ctx);
1195 		if (err < 0)
1196 			goto out;
1197 	}
1198 out:
1199 	return err;
1200 }
1201 
nf_tables_deltable(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)1202 static int nf_tables_deltable(struct net *net, struct sock *nlsk,
1203 			      struct sk_buff *skb, const struct nlmsghdr *nlh,
1204 			      const struct nlattr * const nla[],
1205 			      struct netlink_ext_ack *extack)
1206 {
1207 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1208 	u8 genmask = nft_genmask_next(net);
1209 	int family = nfmsg->nfgen_family;
1210 	const struct nlattr *attr;
1211 	struct nft_table *table;
1212 	struct nft_ctx ctx;
1213 
1214 	nft_ctx_init(&ctx, net, skb, nlh, 0, NULL, NULL, nla);
1215 	if (family == AF_UNSPEC ||
1216 	    (!nla[NFTA_TABLE_NAME] && !nla[NFTA_TABLE_HANDLE]))
1217 		return nft_flush(&ctx, family);
1218 
1219 	if (nla[NFTA_TABLE_HANDLE]) {
1220 		attr = nla[NFTA_TABLE_HANDLE];
1221 		table = nft_table_lookup_byhandle(net, attr, genmask);
1222 	} else {
1223 		attr = nla[NFTA_TABLE_NAME];
1224 		table = nft_table_lookup(net, attr, family, genmask);
1225 	}
1226 
1227 	if (IS_ERR(table)) {
1228 		NL_SET_BAD_ATTR(extack, attr);
1229 		return PTR_ERR(table);
1230 	}
1231 
1232 	if (nlh->nlmsg_flags & NLM_F_NONREC &&
1233 	    table->use > 0)
1234 		return -EBUSY;
1235 
1236 	ctx.family = family;
1237 	ctx.table = table;
1238 
1239 	return nft_flush_table(&ctx);
1240 }
1241 
nf_tables_table_destroy(struct nft_ctx * ctx)1242 static void nf_tables_table_destroy(struct nft_ctx *ctx)
1243 {
1244 	if (WARN_ON(ctx->table->use > 0))
1245 		return;
1246 
1247 	rhltable_destroy(&ctx->table->chains_ht);
1248 	kfree(ctx->table->name);
1249 	kfree(ctx->table->udata);
1250 	kfree(ctx->table);
1251 }
1252 
nft_register_chain_type(const struct nft_chain_type * ctype)1253 void nft_register_chain_type(const struct nft_chain_type *ctype)
1254 {
1255 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
1256 	if (WARN_ON(__nft_chain_type_get(ctype->family, ctype->type))) {
1257 		nfnl_unlock(NFNL_SUBSYS_NFTABLES);
1258 		return;
1259 	}
1260 	chain_type[ctype->family][ctype->type] = ctype;
1261 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
1262 }
1263 EXPORT_SYMBOL_GPL(nft_register_chain_type);
1264 
nft_unregister_chain_type(const struct nft_chain_type * ctype)1265 void nft_unregister_chain_type(const struct nft_chain_type *ctype)
1266 {
1267 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
1268 	chain_type[ctype->family][ctype->type] = NULL;
1269 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
1270 }
1271 EXPORT_SYMBOL_GPL(nft_unregister_chain_type);
1272 
1273 /*
1274  * Chains
1275  */
1276 
1277 static struct nft_chain *
nft_chain_lookup_byhandle(const struct nft_table * table,u64 handle,u8 genmask)1278 nft_chain_lookup_byhandle(const struct nft_table *table, u64 handle, u8 genmask)
1279 {
1280 	struct nft_chain *chain;
1281 
1282 	list_for_each_entry(chain, &table->chains, list) {
1283 		if (chain->handle == handle &&
1284 		    nft_active_genmask(chain, genmask))
1285 			return chain;
1286 	}
1287 
1288 	return ERR_PTR(-ENOENT);
1289 }
1290 
lockdep_commit_lock_is_held(const struct net * net)1291 static bool lockdep_commit_lock_is_held(const struct net *net)
1292 {
1293 #ifdef CONFIG_PROVE_LOCKING
1294 	return lockdep_is_held(&net->nft.commit_mutex);
1295 #else
1296 	return true;
1297 #endif
1298 }
1299 
nft_chain_lookup(struct net * net,struct nft_table * table,const struct nlattr * nla,u8 genmask)1300 static struct nft_chain *nft_chain_lookup(struct net *net,
1301 					  struct nft_table *table,
1302 					  const struct nlattr *nla, u8 genmask)
1303 {
1304 	char search[NFT_CHAIN_MAXNAMELEN + 1];
1305 	struct rhlist_head *tmp, *list;
1306 	struct nft_chain *chain;
1307 
1308 	if (nla == NULL)
1309 		return ERR_PTR(-EINVAL);
1310 
1311 	nla_strlcpy(search, nla, sizeof(search));
1312 
1313 	WARN_ON(!rcu_read_lock_held() &&
1314 		!lockdep_commit_lock_is_held(net));
1315 
1316 	chain = ERR_PTR(-ENOENT);
1317 	rcu_read_lock();
1318 	list = rhltable_lookup(&table->chains_ht, search, nft_chain_ht_params);
1319 	if (!list)
1320 		goto out_unlock;
1321 
1322 	rhl_for_each_entry_rcu(chain, tmp, list, rhlhead) {
1323 		if (nft_active_genmask(chain, genmask))
1324 			goto out_unlock;
1325 	}
1326 	chain = ERR_PTR(-ENOENT);
1327 out_unlock:
1328 	rcu_read_unlock();
1329 	return chain;
1330 }
1331 
1332 static const struct nla_policy nft_chain_policy[NFTA_CHAIN_MAX + 1] = {
1333 	[NFTA_CHAIN_TABLE]	= { .type = NLA_STRING,
1334 				    .len = NFT_TABLE_MAXNAMELEN - 1 },
1335 	[NFTA_CHAIN_HANDLE]	= { .type = NLA_U64 },
1336 	[NFTA_CHAIN_NAME]	= { .type = NLA_STRING,
1337 				    .len = NFT_CHAIN_MAXNAMELEN - 1 },
1338 	[NFTA_CHAIN_HOOK]	= { .type = NLA_NESTED },
1339 	[NFTA_CHAIN_POLICY]	= { .type = NLA_U32 },
1340 	[NFTA_CHAIN_TYPE]	= { .type = NLA_STRING,
1341 				    .len = NFT_MODULE_AUTOLOAD_LIMIT },
1342 	[NFTA_CHAIN_COUNTERS]	= { .type = NLA_NESTED },
1343 	[NFTA_CHAIN_FLAGS]	= { .type = NLA_U32 },
1344 	[NFTA_CHAIN_ID]		= { .type = NLA_U32 },
1345 	[NFTA_CHAIN_USERDATA]	= { .type = NLA_BINARY,
1346 				    .len = NFT_USERDATA_MAXLEN },
1347 };
1348 
1349 static const struct nla_policy nft_hook_policy[NFTA_HOOK_MAX + 1] = {
1350 	[NFTA_HOOK_HOOKNUM]	= { .type = NLA_U32 },
1351 	[NFTA_HOOK_PRIORITY]	= { .type = NLA_U32 },
1352 	[NFTA_HOOK_DEV]		= { .type = NLA_STRING,
1353 				    .len = IFNAMSIZ - 1 },
1354 };
1355 
nft_dump_stats(struct sk_buff * skb,struct nft_stats __percpu * stats)1356 static int nft_dump_stats(struct sk_buff *skb, struct nft_stats __percpu *stats)
1357 {
1358 	struct nft_stats *cpu_stats, total;
1359 	struct nlattr *nest;
1360 	unsigned int seq;
1361 	u64 pkts, bytes;
1362 	int cpu;
1363 
1364 	if (!stats)
1365 		return 0;
1366 
1367 	memset(&total, 0, sizeof(total));
1368 	for_each_possible_cpu(cpu) {
1369 		cpu_stats = per_cpu_ptr(stats, cpu);
1370 		do {
1371 			seq = u64_stats_fetch_begin_irq(&cpu_stats->syncp);
1372 			pkts = cpu_stats->pkts;
1373 			bytes = cpu_stats->bytes;
1374 		} while (u64_stats_fetch_retry_irq(&cpu_stats->syncp, seq));
1375 		total.pkts += pkts;
1376 		total.bytes += bytes;
1377 	}
1378 	nest = nla_nest_start_noflag(skb, NFTA_CHAIN_COUNTERS);
1379 	if (nest == NULL)
1380 		goto nla_put_failure;
1381 
1382 	if (nla_put_be64(skb, NFTA_COUNTER_PACKETS, cpu_to_be64(total.pkts),
1383 			 NFTA_COUNTER_PAD) ||
1384 	    nla_put_be64(skb, NFTA_COUNTER_BYTES, cpu_to_be64(total.bytes),
1385 			 NFTA_COUNTER_PAD))
1386 		goto nla_put_failure;
1387 
1388 	nla_nest_end(skb, nest);
1389 	return 0;
1390 
1391 nla_put_failure:
1392 	return -ENOSPC;
1393 }
1394 
nft_dump_basechain_hook(struct sk_buff * skb,int family,const struct nft_base_chain * basechain)1395 static int nft_dump_basechain_hook(struct sk_buff *skb, int family,
1396 				   const struct nft_base_chain *basechain)
1397 {
1398 	const struct nf_hook_ops *ops = &basechain->ops;
1399 	struct nft_hook *hook, *first = NULL;
1400 	struct nlattr *nest, *nest_devs;
1401 	int n = 0;
1402 
1403 	nest = nla_nest_start_noflag(skb, NFTA_CHAIN_HOOK);
1404 	if (nest == NULL)
1405 		goto nla_put_failure;
1406 	if (nla_put_be32(skb, NFTA_HOOK_HOOKNUM, htonl(ops->hooknum)))
1407 		goto nla_put_failure;
1408 	if (nla_put_be32(skb, NFTA_HOOK_PRIORITY, htonl(ops->priority)))
1409 		goto nla_put_failure;
1410 
1411 	if (nft_base_chain_netdev(family, ops->hooknum)) {
1412 		nest_devs = nla_nest_start_noflag(skb, NFTA_HOOK_DEVS);
1413 		list_for_each_entry(hook, &basechain->hook_list, list) {
1414 			if (!first)
1415 				first = hook;
1416 
1417 			if (nla_put_string(skb, NFTA_DEVICE_NAME,
1418 					   hook->ops.dev->name))
1419 				goto nla_put_failure;
1420 			n++;
1421 		}
1422 		nla_nest_end(skb, nest_devs);
1423 
1424 		if (n == 1 &&
1425 		    nla_put_string(skb, NFTA_HOOK_DEV, first->ops.dev->name))
1426 			goto nla_put_failure;
1427 	}
1428 	nla_nest_end(skb, nest);
1429 
1430 	return 0;
1431 nla_put_failure:
1432 	return -1;
1433 }
1434 
nf_tables_fill_chain_info(struct sk_buff * skb,struct net * net,u32 portid,u32 seq,int event,u32 flags,int family,const struct nft_table * table,const struct nft_chain * chain)1435 static int nf_tables_fill_chain_info(struct sk_buff *skb, struct net *net,
1436 				     u32 portid, u32 seq, int event, u32 flags,
1437 				     int family, const struct nft_table *table,
1438 				     const struct nft_chain *chain)
1439 {
1440 	struct nlmsghdr *nlh;
1441 
1442 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
1443 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
1444 			   NFNETLINK_V0, nft_base_seq(net));
1445 	if (!nlh)
1446 		goto nla_put_failure;
1447 
1448 	if (nla_put_string(skb, NFTA_CHAIN_TABLE, table->name))
1449 		goto nla_put_failure;
1450 	if (nla_put_be64(skb, NFTA_CHAIN_HANDLE, cpu_to_be64(chain->handle),
1451 			 NFTA_CHAIN_PAD))
1452 		goto nla_put_failure;
1453 	if (nla_put_string(skb, NFTA_CHAIN_NAME, chain->name))
1454 		goto nla_put_failure;
1455 
1456 	if (nft_is_base_chain(chain)) {
1457 		const struct nft_base_chain *basechain = nft_base_chain(chain);
1458 		struct nft_stats __percpu *stats;
1459 
1460 		if (nft_dump_basechain_hook(skb, family, basechain))
1461 			goto nla_put_failure;
1462 
1463 		if (nla_put_be32(skb, NFTA_CHAIN_POLICY,
1464 				 htonl(basechain->policy)))
1465 			goto nla_put_failure;
1466 
1467 		if (nla_put_string(skb, NFTA_CHAIN_TYPE, basechain->type->name))
1468 			goto nla_put_failure;
1469 
1470 		stats = rcu_dereference_check(basechain->stats,
1471 					      lockdep_commit_lock_is_held(net));
1472 		if (nft_dump_stats(skb, stats))
1473 			goto nla_put_failure;
1474 	}
1475 
1476 	if (chain->flags &&
1477 	    nla_put_be32(skb, NFTA_CHAIN_FLAGS, htonl(chain->flags)))
1478 		goto nla_put_failure;
1479 
1480 	if (nla_put_be32(skb, NFTA_CHAIN_USE, htonl(chain->use)))
1481 		goto nla_put_failure;
1482 
1483 	if (chain->udata &&
1484 	    nla_put(skb, NFTA_CHAIN_USERDATA, chain->udlen, chain->udata))
1485 		goto nla_put_failure;
1486 
1487 	nlmsg_end(skb, nlh);
1488 	return 0;
1489 
1490 nla_put_failure:
1491 	nlmsg_trim(skb, nlh);
1492 	return -1;
1493 }
1494 
nf_tables_chain_notify(const struct nft_ctx * ctx,int event)1495 static void nf_tables_chain_notify(const struct nft_ctx *ctx, int event)
1496 {
1497 	struct sk_buff *skb;
1498 	int err;
1499 
1500 	if (!ctx->report &&
1501 	    !nfnetlink_has_listeners(ctx->net, NFNLGRP_NFTABLES))
1502 		return;
1503 
1504 	skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1505 	if (skb == NULL)
1506 		goto err;
1507 
1508 	err = nf_tables_fill_chain_info(skb, ctx->net, ctx->portid, ctx->seq,
1509 					event, 0, ctx->family, ctx->table,
1510 					ctx->chain);
1511 	if (err < 0) {
1512 		kfree_skb(skb);
1513 		goto err;
1514 	}
1515 
1516 	nft_notify_enqueue(skb, ctx->report, &ctx->net->nft.notify_list);
1517 	return;
1518 err:
1519 	nfnetlink_set_err(ctx->net, ctx->portid, NFNLGRP_NFTABLES, -ENOBUFS);
1520 }
1521 
nf_tables_dump_chains(struct sk_buff * skb,struct netlink_callback * cb)1522 static int nf_tables_dump_chains(struct sk_buff *skb,
1523 				 struct netlink_callback *cb)
1524 {
1525 	const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1526 	const struct nft_table *table;
1527 	const struct nft_chain *chain;
1528 	unsigned int idx = 0, s_idx = cb->args[0];
1529 	struct net *net = sock_net(skb->sk);
1530 	int family = nfmsg->nfgen_family;
1531 
1532 	rcu_read_lock();
1533 	cb->seq = net->nft.base_seq;
1534 
1535 	list_for_each_entry_rcu(table, &net->nft.tables, list) {
1536 		if (family != NFPROTO_UNSPEC && family != table->family)
1537 			continue;
1538 
1539 		list_for_each_entry_rcu(chain, &table->chains, list) {
1540 			if (idx < s_idx)
1541 				goto cont;
1542 			if (idx > s_idx)
1543 				memset(&cb->args[1], 0,
1544 				       sizeof(cb->args) - sizeof(cb->args[0]));
1545 			if (!nft_is_active(net, chain))
1546 				continue;
1547 			if (nf_tables_fill_chain_info(skb, net,
1548 						      NETLINK_CB(cb->skb).portid,
1549 						      cb->nlh->nlmsg_seq,
1550 						      NFT_MSG_NEWCHAIN,
1551 						      NLM_F_MULTI,
1552 						      table->family, table,
1553 						      chain) < 0)
1554 				goto done;
1555 
1556 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1557 cont:
1558 			idx++;
1559 		}
1560 	}
1561 done:
1562 	rcu_read_unlock();
1563 	cb->args[0] = idx;
1564 	return skb->len;
1565 }
1566 
1567 /* called with rcu_read_lock held */
nf_tables_getchain(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)1568 static int nf_tables_getchain(struct net *net, struct sock *nlsk,
1569 			      struct sk_buff *skb, const struct nlmsghdr *nlh,
1570 			      const struct nlattr * const nla[],
1571 			      struct netlink_ext_ack *extack)
1572 {
1573 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1574 	u8 genmask = nft_genmask_cur(net);
1575 	const struct nft_chain *chain;
1576 	struct nft_table *table;
1577 	struct sk_buff *skb2;
1578 	int family = nfmsg->nfgen_family;
1579 	int err;
1580 
1581 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
1582 		struct netlink_dump_control c = {
1583 			.dump = nf_tables_dump_chains,
1584 			.module = THIS_MODULE,
1585 		};
1586 
1587 		return nft_netlink_dump_start_rcu(nlsk, skb, nlh, &c);
1588 	}
1589 
1590 	table = nft_table_lookup(net, nla[NFTA_CHAIN_TABLE], family, genmask);
1591 	if (IS_ERR(table)) {
1592 		NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_TABLE]);
1593 		return PTR_ERR(table);
1594 	}
1595 
1596 	chain = nft_chain_lookup(net, table, nla[NFTA_CHAIN_NAME], genmask);
1597 	if (IS_ERR(chain)) {
1598 		NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_NAME]);
1599 		return PTR_ERR(chain);
1600 	}
1601 
1602 	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1603 	if (!skb2)
1604 		return -ENOMEM;
1605 
1606 	err = nf_tables_fill_chain_info(skb2, net, NETLINK_CB(skb).portid,
1607 					nlh->nlmsg_seq, NFT_MSG_NEWCHAIN, 0,
1608 					family, table, chain);
1609 	if (err < 0)
1610 		goto err_fill_chain_info;
1611 
1612 	return nfnetlink_unicast(skb2, net, NETLINK_CB(skb).portid);
1613 
1614 err_fill_chain_info:
1615 	kfree_skb(skb2);
1616 	return err;
1617 }
1618 
1619 static const struct nla_policy nft_counter_policy[NFTA_COUNTER_MAX + 1] = {
1620 	[NFTA_COUNTER_PACKETS]	= { .type = NLA_U64 },
1621 	[NFTA_COUNTER_BYTES]	= { .type = NLA_U64 },
1622 };
1623 
nft_stats_alloc(const struct nlattr * attr)1624 static struct nft_stats __percpu *nft_stats_alloc(const struct nlattr *attr)
1625 {
1626 	struct nlattr *tb[NFTA_COUNTER_MAX+1];
1627 	struct nft_stats __percpu *newstats;
1628 	struct nft_stats *stats;
1629 	int err;
1630 
1631 	err = nla_parse_nested_deprecated(tb, NFTA_COUNTER_MAX, attr,
1632 					  nft_counter_policy, NULL);
1633 	if (err < 0)
1634 		return ERR_PTR(err);
1635 
1636 	if (!tb[NFTA_COUNTER_BYTES] || !tb[NFTA_COUNTER_PACKETS])
1637 		return ERR_PTR(-EINVAL);
1638 
1639 	newstats = netdev_alloc_pcpu_stats(struct nft_stats);
1640 	if (newstats == NULL)
1641 		return ERR_PTR(-ENOMEM);
1642 
1643 	/* Restore old counters on this cpu, no problem. Per-cpu statistics
1644 	 * are not exposed to userspace.
1645 	 */
1646 	preempt_disable();
1647 	stats = this_cpu_ptr(newstats);
1648 	stats->bytes = be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_BYTES]));
1649 	stats->pkts = be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_PACKETS]));
1650 	preempt_enable();
1651 
1652 	return newstats;
1653 }
1654 
nft_chain_stats_replace(struct nft_trans * trans)1655 static void nft_chain_stats_replace(struct nft_trans *trans)
1656 {
1657 	struct nft_base_chain *chain = nft_base_chain(trans->ctx.chain);
1658 
1659 	if (!nft_trans_chain_stats(trans))
1660 		return;
1661 
1662 	nft_trans_chain_stats(trans) =
1663 		rcu_replace_pointer(chain->stats, nft_trans_chain_stats(trans),
1664 				    lockdep_commit_lock_is_held(trans->ctx.net));
1665 
1666 	if (!nft_trans_chain_stats(trans))
1667 		static_branch_inc(&nft_counters_enabled);
1668 }
1669 
nf_tables_chain_free_chain_rules(struct nft_chain * chain)1670 static void nf_tables_chain_free_chain_rules(struct nft_chain *chain)
1671 {
1672 	struct nft_rule **g0 = rcu_dereference_raw(chain->rules_gen_0);
1673 	struct nft_rule **g1 = rcu_dereference_raw(chain->rules_gen_1);
1674 
1675 	if (g0 != g1)
1676 		kvfree(g1);
1677 	kvfree(g0);
1678 
1679 	/* should be NULL either via abort or via successful commit */
1680 	WARN_ON_ONCE(chain->rules_next);
1681 	kvfree(chain->rules_next);
1682 }
1683 
nf_tables_chain_destroy(struct nft_ctx * ctx)1684 void nf_tables_chain_destroy(struct nft_ctx *ctx)
1685 {
1686 	struct nft_chain *chain = ctx->chain;
1687 	struct nft_hook *hook, *next;
1688 
1689 	if (WARN_ON(chain->use > 0))
1690 		return;
1691 
1692 	/* no concurrent access possible anymore */
1693 	nf_tables_chain_free_chain_rules(chain);
1694 
1695 	if (nft_is_base_chain(chain)) {
1696 		struct nft_base_chain *basechain = nft_base_chain(chain);
1697 
1698 		if (nft_base_chain_netdev(ctx->family, basechain->ops.hooknum)) {
1699 			list_for_each_entry_safe(hook, next,
1700 						 &basechain->hook_list, list) {
1701 				list_del_rcu(&hook->list);
1702 				kfree_rcu(hook, rcu);
1703 			}
1704 		}
1705 		module_put(basechain->type->owner);
1706 		if (rcu_access_pointer(basechain->stats)) {
1707 			static_branch_dec(&nft_counters_enabled);
1708 			free_percpu(rcu_dereference_raw(basechain->stats));
1709 		}
1710 		kfree(chain->name);
1711 		kfree(chain->udata);
1712 		kfree(basechain);
1713 	} else {
1714 		kfree(chain->name);
1715 		kfree(chain->udata);
1716 		kfree(chain);
1717 	}
1718 }
1719 
nft_netdev_hook_alloc(struct net * net,const struct nlattr * attr)1720 static struct nft_hook *nft_netdev_hook_alloc(struct net *net,
1721 					      const struct nlattr *attr)
1722 {
1723 	struct net_device *dev;
1724 	char ifname[IFNAMSIZ];
1725 	struct nft_hook *hook;
1726 	int err;
1727 
1728 	hook = kmalloc(sizeof(struct nft_hook), GFP_KERNEL);
1729 	if (!hook) {
1730 		err = -ENOMEM;
1731 		goto err_hook_alloc;
1732 	}
1733 
1734 	nla_strlcpy(ifname, attr, IFNAMSIZ);
1735 	/* nf_tables_netdev_event() is called under rtnl_mutex, this is
1736 	 * indirectly serializing all the other holders of the commit_mutex with
1737 	 * the rtnl_mutex.
1738 	 */
1739 	dev = __dev_get_by_name(net, ifname);
1740 	if (!dev) {
1741 		err = -ENOENT;
1742 		goto err_hook_dev;
1743 	}
1744 	hook->ops.dev = dev;
1745 
1746 	return hook;
1747 
1748 err_hook_dev:
1749 	kfree(hook);
1750 err_hook_alloc:
1751 	return ERR_PTR(err);
1752 }
1753 
nft_hook_list_find(struct list_head * hook_list,const struct nft_hook * this)1754 static struct nft_hook *nft_hook_list_find(struct list_head *hook_list,
1755 					   const struct nft_hook *this)
1756 {
1757 	struct nft_hook *hook;
1758 
1759 	list_for_each_entry(hook, hook_list, list) {
1760 		if (this->ops.dev == hook->ops.dev)
1761 			return hook;
1762 	}
1763 
1764 	return NULL;
1765 }
1766 
nf_tables_parse_netdev_hooks(struct net * net,const struct nlattr * attr,struct list_head * hook_list)1767 static int nf_tables_parse_netdev_hooks(struct net *net,
1768 					const struct nlattr *attr,
1769 					struct list_head *hook_list)
1770 {
1771 	struct nft_hook *hook, *next;
1772 	const struct nlattr *tmp;
1773 	int rem, n = 0, err;
1774 
1775 	nla_for_each_nested(tmp, attr, rem) {
1776 		if (nla_type(tmp) != NFTA_DEVICE_NAME) {
1777 			err = -EINVAL;
1778 			goto err_hook;
1779 		}
1780 
1781 		hook = nft_netdev_hook_alloc(net, tmp);
1782 		if (IS_ERR(hook)) {
1783 			err = PTR_ERR(hook);
1784 			goto err_hook;
1785 		}
1786 		if (nft_hook_list_find(hook_list, hook)) {
1787 			kfree(hook);
1788 			err = -EEXIST;
1789 			goto err_hook;
1790 		}
1791 		list_add_tail(&hook->list, hook_list);
1792 		n++;
1793 
1794 		if (n == NFT_NETDEVICE_MAX) {
1795 			err = -EFBIG;
1796 			goto err_hook;
1797 		}
1798 	}
1799 
1800 	return 0;
1801 
1802 err_hook:
1803 	list_for_each_entry_safe(hook, next, hook_list, list) {
1804 		list_del(&hook->list);
1805 		kfree(hook);
1806 	}
1807 	return err;
1808 }
1809 
1810 struct nft_chain_hook {
1811 	u32				num;
1812 	s32				priority;
1813 	const struct nft_chain_type	*type;
1814 	struct list_head		list;
1815 };
1816 
nft_chain_parse_netdev(struct net * net,struct nlattr * tb[],struct list_head * hook_list)1817 static int nft_chain_parse_netdev(struct net *net,
1818 				  struct nlattr *tb[],
1819 				  struct list_head *hook_list)
1820 {
1821 	struct nft_hook *hook;
1822 	int err;
1823 
1824 	if (tb[NFTA_HOOK_DEV]) {
1825 		hook = nft_netdev_hook_alloc(net, tb[NFTA_HOOK_DEV]);
1826 		if (IS_ERR(hook))
1827 			return PTR_ERR(hook);
1828 
1829 		list_add_tail(&hook->list, hook_list);
1830 	} else if (tb[NFTA_HOOK_DEVS]) {
1831 		err = nf_tables_parse_netdev_hooks(net, tb[NFTA_HOOK_DEVS],
1832 						   hook_list);
1833 		if (err < 0)
1834 			return err;
1835 
1836 		if (list_empty(hook_list))
1837 			return -EINVAL;
1838 	} else {
1839 		return -EINVAL;
1840 	}
1841 
1842 	return 0;
1843 }
1844 
nft_chain_parse_hook(struct net * net,const struct nlattr * const nla[],struct nft_chain_hook * hook,u8 family,bool autoload)1845 static int nft_chain_parse_hook(struct net *net,
1846 				const struct nlattr * const nla[],
1847 				struct nft_chain_hook *hook, u8 family,
1848 				bool autoload)
1849 {
1850 	struct nlattr *ha[NFTA_HOOK_MAX + 1];
1851 	const struct nft_chain_type *type;
1852 	int err;
1853 
1854 	lockdep_assert_held(&net->nft.commit_mutex);
1855 	lockdep_nfnl_nft_mutex_not_held();
1856 
1857 	err = nla_parse_nested_deprecated(ha, NFTA_HOOK_MAX,
1858 					  nla[NFTA_CHAIN_HOOK],
1859 					  nft_hook_policy, NULL);
1860 	if (err < 0)
1861 		return err;
1862 
1863 	if (ha[NFTA_HOOK_HOOKNUM] == NULL ||
1864 	    ha[NFTA_HOOK_PRIORITY] == NULL)
1865 		return -EINVAL;
1866 
1867 	hook->num = ntohl(nla_get_be32(ha[NFTA_HOOK_HOOKNUM]));
1868 	hook->priority = ntohl(nla_get_be32(ha[NFTA_HOOK_PRIORITY]));
1869 
1870 	type = __nft_chain_type_get(family, NFT_CHAIN_T_DEFAULT);
1871 	if (!type)
1872 		return -EOPNOTSUPP;
1873 
1874 	if (nla[NFTA_CHAIN_TYPE]) {
1875 		type = nf_tables_chain_type_lookup(net, nla[NFTA_CHAIN_TYPE],
1876 						   family, autoload);
1877 		if (IS_ERR(type))
1878 			return PTR_ERR(type);
1879 	}
1880 	if (hook->num >= NFT_MAX_HOOKS || !(type->hook_mask & (1 << hook->num)))
1881 		return -EOPNOTSUPP;
1882 
1883 	if (type->type == NFT_CHAIN_T_NAT &&
1884 	    hook->priority <= NF_IP_PRI_CONNTRACK)
1885 		return -EOPNOTSUPP;
1886 
1887 	if (!try_module_get(type->owner))
1888 		return -ENOENT;
1889 
1890 	hook->type = type;
1891 
1892 	INIT_LIST_HEAD(&hook->list);
1893 	if (nft_base_chain_netdev(family, hook->num)) {
1894 		err = nft_chain_parse_netdev(net, ha, &hook->list);
1895 		if (err < 0) {
1896 			module_put(type->owner);
1897 			return err;
1898 		}
1899 	} else if (ha[NFTA_HOOK_DEV] || ha[NFTA_HOOK_DEVS]) {
1900 		module_put(type->owner);
1901 		return -EOPNOTSUPP;
1902 	}
1903 
1904 	return 0;
1905 }
1906 
nft_chain_release_hook(struct nft_chain_hook * hook)1907 static void nft_chain_release_hook(struct nft_chain_hook *hook)
1908 {
1909 	struct nft_hook *h, *next;
1910 
1911 	list_for_each_entry_safe(h, next, &hook->list, list) {
1912 		list_del(&h->list);
1913 		kfree(h);
1914 	}
1915 	module_put(hook->type->owner);
1916 }
1917 
1918 struct nft_rules_old {
1919 	struct rcu_head h;
1920 	struct nft_rule **start;
1921 };
1922 
nf_tables_chain_alloc_rules(const struct nft_chain * chain,unsigned int alloc)1923 static struct nft_rule **nf_tables_chain_alloc_rules(const struct nft_chain *chain,
1924 						     unsigned int alloc)
1925 {
1926 	if (alloc > INT_MAX)
1927 		return NULL;
1928 
1929 	alloc += 1;	/* NULL, ends rules */
1930 	if (sizeof(struct nft_rule *) > INT_MAX / alloc)
1931 		return NULL;
1932 
1933 	alloc *= sizeof(struct nft_rule *);
1934 	alloc += sizeof(struct nft_rules_old);
1935 
1936 	return kvmalloc(alloc, GFP_KERNEL);
1937 }
1938 
nft_basechain_hook_init(struct nf_hook_ops * ops,u8 family,const struct nft_chain_hook * hook,struct nft_chain * chain)1939 static void nft_basechain_hook_init(struct nf_hook_ops *ops, u8 family,
1940 				    const struct nft_chain_hook *hook,
1941 				    struct nft_chain *chain)
1942 {
1943 	ops->pf		= family;
1944 	ops->hooknum	= hook->num;
1945 	ops->priority	= hook->priority;
1946 	ops->priv	= chain;
1947 	ops->hook	= hook->type->hooks[ops->hooknum];
1948 }
1949 
nft_basechain_init(struct nft_base_chain * basechain,u8 family,struct nft_chain_hook * hook,u32 flags)1950 static int nft_basechain_init(struct nft_base_chain *basechain, u8 family,
1951 			      struct nft_chain_hook *hook, u32 flags)
1952 {
1953 	struct nft_chain *chain;
1954 	struct nft_hook *h;
1955 
1956 	basechain->type = hook->type;
1957 	INIT_LIST_HEAD(&basechain->hook_list);
1958 	chain = &basechain->chain;
1959 
1960 	if (nft_base_chain_netdev(family, hook->num)) {
1961 		list_splice_init(&hook->list, &basechain->hook_list);
1962 		list_for_each_entry(h, &basechain->hook_list, list)
1963 			nft_basechain_hook_init(&h->ops, family, hook, chain);
1964 
1965 		basechain->ops.hooknum	= hook->num;
1966 		basechain->ops.priority	= hook->priority;
1967 	} else {
1968 		nft_basechain_hook_init(&basechain->ops, family, hook, chain);
1969 	}
1970 
1971 	chain->flags |= NFT_CHAIN_BASE | flags;
1972 	basechain->policy = NF_ACCEPT;
1973 	if (chain->flags & NFT_CHAIN_HW_OFFLOAD &&
1974 	    !nft_chain_offload_support(basechain)) {
1975 		list_splice_init(&basechain->hook_list, &hook->list);
1976 		return -EOPNOTSUPP;
1977 	}
1978 
1979 	flow_block_init(&basechain->flow_block);
1980 
1981 	return 0;
1982 }
1983 
nft_chain_add(struct nft_table * table,struct nft_chain * chain)1984 static int nft_chain_add(struct nft_table *table, struct nft_chain *chain)
1985 {
1986 	int err;
1987 
1988 	err = rhltable_insert_key(&table->chains_ht, chain->name,
1989 				  &chain->rhlhead, nft_chain_ht_params);
1990 	if (err)
1991 		return err;
1992 
1993 	list_add_tail_rcu(&chain->list, &table->chains);
1994 
1995 	return 0;
1996 }
1997 
1998 static u64 chain_id;
1999 
nf_tables_addchain(struct nft_ctx * ctx,u8 family,u8 genmask,u8 policy,u32 flags)2000 static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
2001 			      u8 policy, u32 flags)
2002 {
2003 	const struct nlattr * const *nla = ctx->nla;
2004 	struct nft_table *table = ctx->table;
2005 	struct nft_base_chain *basechain;
2006 	struct net *net = ctx->net;
2007 	char name[NFT_NAME_MAXLEN];
2008 	struct nft_trans *trans;
2009 	struct nft_chain *chain;
2010 	struct nft_rule **rules;
2011 	int err;
2012 
2013 	if (table->use == UINT_MAX)
2014 		return -EOVERFLOW;
2015 
2016 	if (nla[NFTA_CHAIN_HOOK]) {
2017 		struct nft_stats __percpu *stats = NULL;
2018 		struct nft_chain_hook hook;
2019 
2020 		if (flags & NFT_CHAIN_BINDING)
2021 			return -EOPNOTSUPP;
2022 
2023 		err = nft_chain_parse_hook(net, nla, &hook, family, true);
2024 		if (err < 0)
2025 			return err;
2026 
2027 		basechain = kzalloc(sizeof(*basechain), GFP_KERNEL);
2028 		if (basechain == NULL) {
2029 			nft_chain_release_hook(&hook);
2030 			return -ENOMEM;
2031 		}
2032 		chain = &basechain->chain;
2033 
2034 		if (nla[NFTA_CHAIN_COUNTERS]) {
2035 			stats = nft_stats_alloc(nla[NFTA_CHAIN_COUNTERS]);
2036 			if (IS_ERR(stats)) {
2037 				nft_chain_release_hook(&hook);
2038 				kfree(basechain);
2039 				return PTR_ERR(stats);
2040 			}
2041 			rcu_assign_pointer(basechain->stats, stats);
2042 		}
2043 
2044 		err = nft_basechain_init(basechain, family, &hook, flags);
2045 		if (err < 0) {
2046 			nft_chain_release_hook(&hook);
2047 			kfree(basechain);
2048 			free_percpu(stats);
2049 			return err;
2050 		}
2051 		if (stats)
2052 			static_branch_inc(&nft_counters_enabled);
2053 	} else {
2054 		if (flags & NFT_CHAIN_BASE)
2055 			return -EINVAL;
2056 		if (flags & NFT_CHAIN_HW_OFFLOAD)
2057 			return -EOPNOTSUPP;
2058 
2059 		chain = kzalloc(sizeof(*chain), GFP_KERNEL);
2060 		if (chain == NULL)
2061 			return -ENOMEM;
2062 
2063 		chain->flags = flags;
2064 	}
2065 	ctx->chain = chain;
2066 
2067 	INIT_LIST_HEAD(&chain->rules);
2068 	chain->handle = nf_tables_alloc_handle(table);
2069 	chain->table = table;
2070 
2071 	if (nla[NFTA_CHAIN_NAME]) {
2072 		chain->name = nla_strdup(nla[NFTA_CHAIN_NAME], GFP_KERNEL);
2073 	} else {
2074 		if (!(flags & NFT_CHAIN_BINDING)) {
2075 			err = -EINVAL;
2076 			goto err_destroy_chain;
2077 		}
2078 
2079 		snprintf(name, sizeof(name), "__chain%llu", ++chain_id);
2080 		chain->name = kstrdup(name, GFP_KERNEL);
2081 	}
2082 
2083 	if (!chain->name) {
2084 		err = -ENOMEM;
2085 		goto err_destroy_chain;
2086 	}
2087 
2088 	if (nla[NFTA_CHAIN_USERDATA]) {
2089 		chain->udata = nla_memdup(nla[NFTA_CHAIN_USERDATA], GFP_KERNEL);
2090 		if (chain->udata == NULL) {
2091 			err = -ENOMEM;
2092 			goto err_destroy_chain;
2093 		}
2094 		chain->udlen = nla_len(nla[NFTA_CHAIN_USERDATA]);
2095 	}
2096 
2097 	rules = nf_tables_chain_alloc_rules(chain, 0);
2098 	if (!rules) {
2099 		err = -ENOMEM;
2100 		goto err_destroy_chain;
2101 	}
2102 
2103 	*rules = NULL;
2104 	rcu_assign_pointer(chain->rules_gen_0, rules);
2105 	rcu_assign_pointer(chain->rules_gen_1, rules);
2106 
2107 	err = nf_tables_register_hook(net, table, chain);
2108 	if (err < 0)
2109 		goto err_destroy_chain;
2110 
2111 	trans = nft_trans_chain_add(ctx, NFT_MSG_NEWCHAIN);
2112 	if (IS_ERR(trans)) {
2113 		err = PTR_ERR(trans);
2114 		goto err_unregister_hook;
2115 	}
2116 
2117 	nft_trans_chain_policy(trans) = NFT_CHAIN_POLICY_UNSET;
2118 	if (nft_is_base_chain(chain))
2119 		nft_trans_chain_policy(trans) = policy;
2120 
2121 	err = nft_chain_add(table, chain);
2122 	if (err < 0) {
2123 		nft_trans_destroy(trans);
2124 		goto err_unregister_hook;
2125 	}
2126 
2127 	table->use++;
2128 
2129 	return 0;
2130 err_unregister_hook:
2131 	nf_tables_unregister_hook(net, table, chain);
2132 err_destroy_chain:
2133 	nf_tables_chain_destroy(ctx);
2134 
2135 	return err;
2136 }
2137 
nft_hook_list_equal(struct list_head * hook_list1,struct list_head * hook_list2)2138 static bool nft_hook_list_equal(struct list_head *hook_list1,
2139 				struct list_head *hook_list2)
2140 {
2141 	struct nft_hook *hook;
2142 	int n = 0, m = 0;
2143 
2144 	n = 0;
2145 	list_for_each_entry(hook, hook_list2, list) {
2146 		if (!nft_hook_list_find(hook_list1, hook))
2147 			return false;
2148 
2149 		n++;
2150 	}
2151 	list_for_each_entry(hook, hook_list1, list)
2152 		m++;
2153 
2154 	return n == m;
2155 }
2156 
nf_tables_updchain(struct nft_ctx * ctx,u8 genmask,u8 policy,u32 flags,const struct nlattr * attr,struct netlink_ext_ack * extack)2157 static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy,
2158 			      u32 flags, const struct nlattr *attr,
2159 			      struct netlink_ext_ack *extack)
2160 {
2161 	const struct nlattr * const *nla = ctx->nla;
2162 	struct nft_table *table = ctx->table;
2163 	struct nft_chain *chain = ctx->chain;
2164 	struct nft_base_chain *basechain;
2165 	struct nft_stats *stats = NULL;
2166 	struct nft_chain_hook hook;
2167 	struct nf_hook_ops *ops;
2168 	struct nft_trans *trans;
2169 	int err;
2170 
2171 	if (chain->flags ^ flags)
2172 		return -EOPNOTSUPP;
2173 
2174 	if (nla[NFTA_CHAIN_HOOK]) {
2175 		if (!nft_is_base_chain(chain)) {
2176 			NL_SET_BAD_ATTR(extack, attr);
2177 			return -EEXIST;
2178 		}
2179 		err = nft_chain_parse_hook(ctx->net, nla, &hook, ctx->family,
2180 					   false);
2181 		if (err < 0)
2182 			return err;
2183 
2184 		basechain = nft_base_chain(chain);
2185 		if (basechain->type != hook.type) {
2186 			nft_chain_release_hook(&hook);
2187 			NL_SET_BAD_ATTR(extack, attr);
2188 			return -EEXIST;
2189 		}
2190 
2191 		if (nft_base_chain_netdev(ctx->family, hook.num)) {
2192 			if (!nft_hook_list_equal(&basechain->hook_list,
2193 						 &hook.list)) {
2194 				nft_chain_release_hook(&hook);
2195 				NL_SET_BAD_ATTR(extack, attr);
2196 				return -EEXIST;
2197 			}
2198 		} else {
2199 			ops = &basechain->ops;
2200 			if (ops->hooknum != hook.num ||
2201 			    ops->priority != hook.priority) {
2202 				nft_chain_release_hook(&hook);
2203 				NL_SET_BAD_ATTR(extack, attr);
2204 				return -EEXIST;
2205 			}
2206 		}
2207 		nft_chain_release_hook(&hook);
2208 	}
2209 
2210 	if (nla[NFTA_CHAIN_HANDLE] &&
2211 	    nla[NFTA_CHAIN_NAME]) {
2212 		struct nft_chain *chain2;
2213 
2214 		chain2 = nft_chain_lookup(ctx->net, table,
2215 					  nla[NFTA_CHAIN_NAME], genmask);
2216 		if (!IS_ERR(chain2)) {
2217 			NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_NAME]);
2218 			return -EEXIST;
2219 		}
2220 	}
2221 
2222 	if (nla[NFTA_CHAIN_COUNTERS]) {
2223 		if (!nft_is_base_chain(chain))
2224 			return -EOPNOTSUPP;
2225 
2226 		stats = nft_stats_alloc(nla[NFTA_CHAIN_COUNTERS]);
2227 		if (IS_ERR(stats))
2228 			return PTR_ERR(stats);
2229 	}
2230 
2231 	err = -ENOMEM;
2232 	trans = nft_trans_alloc(ctx, NFT_MSG_NEWCHAIN,
2233 				sizeof(struct nft_trans_chain));
2234 	if (trans == NULL)
2235 		goto err;
2236 
2237 	nft_trans_chain_stats(trans) = stats;
2238 	nft_trans_chain_update(trans) = true;
2239 
2240 	if (nla[NFTA_CHAIN_POLICY])
2241 		nft_trans_chain_policy(trans) = policy;
2242 	else
2243 		nft_trans_chain_policy(trans) = -1;
2244 
2245 	if (nla[NFTA_CHAIN_HANDLE] &&
2246 	    nla[NFTA_CHAIN_NAME]) {
2247 		struct nft_trans *tmp;
2248 		char *name;
2249 
2250 		err = -ENOMEM;
2251 		name = nla_strdup(nla[NFTA_CHAIN_NAME], GFP_KERNEL);
2252 		if (!name)
2253 			goto err;
2254 
2255 		err = -EEXIST;
2256 		list_for_each_entry(tmp, &ctx->net->nft.commit_list, list) {
2257 			if (tmp->msg_type == NFT_MSG_NEWCHAIN &&
2258 			    tmp->ctx.table == table &&
2259 			    nft_trans_chain_update(tmp) &&
2260 			    nft_trans_chain_name(tmp) &&
2261 			    strcmp(name, nft_trans_chain_name(tmp)) == 0) {
2262 				NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_NAME]);
2263 				kfree(name);
2264 				goto err;
2265 			}
2266 		}
2267 
2268 		nft_trans_chain_name(trans) = name;
2269 	}
2270 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
2271 
2272 	return 0;
2273 err:
2274 	free_percpu(stats);
2275 	kfree(trans);
2276 	return err;
2277 }
2278 
nft_chain_lookup_byid(const struct net * net,const struct nft_table * table,const struct nlattr * nla)2279 static struct nft_chain *nft_chain_lookup_byid(const struct net *net,
2280 					       const struct nft_table *table,
2281 					       const struct nlattr *nla)
2282 {
2283 	u32 id = ntohl(nla_get_be32(nla));
2284 	struct nft_trans *trans;
2285 
2286 	list_for_each_entry(trans, &net->nft.commit_list, list) {
2287 		struct nft_chain *chain = trans->ctx.chain;
2288 
2289 		if (trans->msg_type == NFT_MSG_NEWCHAIN &&
2290 		    chain->table == table &&
2291 		    id == nft_trans_chain_id(trans))
2292 			return chain;
2293 	}
2294 	return ERR_PTR(-ENOENT);
2295 }
2296 
nf_tables_newchain(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)2297 static int nf_tables_newchain(struct net *net, struct sock *nlsk,
2298 			      struct sk_buff *skb, const struct nlmsghdr *nlh,
2299 			      const struct nlattr * const nla[],
2300 			      struct netlink_ext_ack *extack)
2301 {
2302 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
2303 	u8 genmask = nft_genmask_next(net);
2304 	int family = nfmsg->nfgen_family;
2305 	struct nft_chain *chain = NULL;
2306 	const struct nlattr *attr;
2307 	struct nft_table *table;
2308 	u8 policy = NF_ACCEPT;
2309 	struct nft_ctx ctx;
2310 	u64 handle = 0;
2311 	u32 flags = 0;
2312 
2313 	lockdep_assert_held(&net->nft.commit_mutex);
2314 
2315 	table = nft_table_lookup(net, nla[NFTA_CHAIN_TABLE], family, genmask);
2316 	if (IS_ERR(table)) {
2317 		NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_TABLE]);
2318 		return PTR_ERR(table);
2319 	}
2320 
2321 	chain = NULL;
2322 	attr = nla[NFTA_CHAIN_NAME];
2323 
2324 	if (nla[NFTA_CHAIN_HANDLE]) {
2325 		handle = be64_to_cpu(nla_get_be64(nla[NFTA_CHAIN_HANDLE]));
2326 		chain = nft_chain_lookup_byhandle(table, handle, genmask);
2327 		if (IS_ERR(chain)) {
2328 			NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_HANDLE]);
2329 			return PTR_ERR(chain);
2330 		}
2331 		attr = nla[NFTA_CHAIN_HANDLE];
2332 	} else if (nla[NFTA_CHAIN_NAME]) {
2333 		chain = nft_chain_lookup(net, table, attr, genmask);
2334 		if (IS_ERR(chain)) {
2335 			if (PTR_ERR(chain) != -ENOENT) {
2336 				NL_SET_BAD_ATTR(extack, attr);
2337 				return PTR_ERR(chain);
2338 			}
2339 			chain = NULL;
2340 		}
2341 	} else if (!nla[NFTA_CHAIN_ID]) {
2342 		return -EINVAL;
2343 	}
2344 
2345 	if (nla[NFTA_CHAIN_POLICY]) {
2346 		if (chain != NULL &&
2347 		    !nft_is_base_chain(chain)) {
2348 			NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_POLICY]);
2349 			return -EOPNOTSUPP;
2350 		}
2351 
2352 		if (chain == NULL &&
2353 		    nla[NFTA_CHAIN_HOOK] == NULL) {
2354 			NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_POLICY]);
2355 			return -EOPNOTSUPP;
2356 		}
2357 
2358 		policy = ntohl(nla_get_be32(nla[NFTA_CHAIN_POLICY]));
2359 		switch (policy) {
2360 		case NF_DROP:
2361 		case NF_ACCEPT:
2362 			break;
2363 		default:
2364 			return -EINVAL;
2365 		}
2366 	}
2367 
2368 	if (nla[NFTA_CHAIN_FLAGS])
2369 		flags = ntohl(nla_get_be32(nla[NFTA_CHAIN_FLAGS]));
2370 	else if (chain)
2371 		flags = chain->flags;
2372 
2373 	if (flags & ~NFT_CHAIN_FLAGS)
2374 		return -EOPNOTSUPP;
2375 
2376 	nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
2377 
2378 	if (chain != NULL) {
2379 		if (nlh->nlmsg_flags & NLM_F_EXCL) {
2380 			NL_SET_BAD_ATTR(extack, attr);
2381 			return -EEXIST;
2382 		}
2383 		if (nlh->nlmsg_flags & NLM_F_REPLACE)
2384 			return -EOPNOTSUPP;
2385 
2386 		flags |= chain->flags & NFT_CHAIN_BASE;
2387 		return nf_tables_updchain(&ctx, genmask, policy, flags, attr,
2388 					  extack);
2389 	}
2390 
2391 	return nf_tables_addchain(&ctx, family, genmask, policy, flags);
2392 }
2393 
nf_tables_delchain(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)2394 static int nf_tables_delchain(struct net *net, struct sock *nlsk,
2395 			      struct sk_buff *skb, const struct nlmsghdr *nlh,
2396 			      const struct nlattr * const nla[],
2397 			      struct netlink_ext_ack *extack)
2398 {
2399 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
2400 	u8 genmask = nft_genmask_next(net);
2401 	int family = nfmsg->nfgen_family;
2402 	const struct nlattr *attr;
2403 	struct nft_table *table;
2404 	struct nft_chain *chain;
2405 	struct nft_rule *rule;
2406 	struct nft_ctx ctx;
2407 	u64 handle;
2408 	u32 use;
2409 	int err;
2410 
2411 	table = nft_table_lookup(net, nla[NFTA_CHAIN_TABLE], family, genmask);
2412 	if (IS_ERR(table)) {
2413 		NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_TABLE]);
2414 		return PTR_ERR(table);
2415 	}
2416 
2417 	if (nla[NFTA_CHAIN_HANDLE]) {
2418 		attr = nla[NFTA_CHAIN_HANDLE];
2419 		handle = be64_to_cpu(nla_get_be64(attr));
2420 		chain = nft_chain_lookup_byhandle(table, handle, genmask);
2421 	} else {
2422 		attr = nla[NFTA_CHAIN_NAME];
2423 		chain = nft_chain_lookup(net, table, attr, genmask);
2424 	}
2425 	if (IS_ERR(chain)) {
2426 		NL_SET_BAD_ATTR(extack, attr);
2427 		return PTR_ERR(chain);
2428 	}
2429 
2430 	if (nlh->nlmsg_flags & NLM_F_NONREC &&
2431 	    chain->use > 0)
2432 		return -EBUSY;
2433 
2434 	nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
2435 
2436 	use = chain->use;
2437 	list_for_each_entry(rule, &chain->rules, list) {
2438 		if (!nft_is_active_next(net, rule))
2439 			continue;
2440 		use--;
2441 
2442 		err = nft_delrule(&ctx, rule);
2443 		if (err < 0)
2444 			return err;
2445 	}
2446 
2447 	/* There are rules and elements that are still holding references to us,
2448 	 * we cannot do a recursive removal in this case.
2449 	 */
2450 	if (use > 0) {
2451 		NL_SET_BAD_ATTR(extack, attr);
2452 		return -EBUSY;
2453 	}
2454 
2455 	return nft_delchain(&ctx);
2456 }
2457 
2458 /*
2459  * Expressions
2460  */
2461 
2462 /**
2463  *	nft_register_expr - register nf_tables expr type
2464  *	@type: expr type
2465  *
2466  *	Registers the expr type for use with nf_tables. Returns zero on
2467  *	success or a negative errno code otherwise.
2468  */
nft_register_expr(struct nft_expr_type * type)2469 int nft_register_expr(struct nft_expr_type *type)
2470 {
2471 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
2472 	if (type->family == NFPROTO_UNSPEC)
2473 		list_add_tail_rcu(&type->list, &nf_tables_expressions);
2474 	else
2475 		list_add_rcu(&type->list, &nf_tables_expressions);
2476 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
2477 	return 0;
2478 }
2479 EXPORT_SYMBOL_GPL(nft_register_expr);
2480 
2481 /**
2482  *	nft_unregister_expr - unregister nf_tables expr type
2483  *	@type: expr type
2484  *
2485  * 	Unregisters the expr typefor use with nf_tables.
2486  */
nft_unregister_expr(struct nft_expr_type * type)2487 void nft_unregister_expr(struct nft_expr_type *type)
2488 {
2489 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
2490 	list_del_rcu(&type->list);
2491 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
2492 }
2493 EXPORT_SYMBOL_GPL(nft_unregister_expr);
2494 
__nft_expr_type_get(u8 family,struct nlattr * nla)2495 static const struct nft_expr_type *__nft_expr_type_get(u8 family,
2496 						       struct nlattr *nla)
2497 {
2498 	const struct nft_expr_type *type, *candidate = NULL;
2499 
2500 	list_for_each_entry(type, &nf_tables_expressions, list) {
2501 		if (!nla_strcmp(nla, type->name)) {
2502 			if (!type->family && !candidate)
2503 				candidate = type;
2504 			else if (type->family == family)
2505 				candidate = type;
2506 		}
2507 	}
2508 	return candidate;
2509 }
2510 
2511 #ifdef CONFIG_MODULES
nft_expr_type_request_module(struct net * net,u8 family,struct nlattr * nla)2512 static int nft_expr_type_request_module(struct net *net, u8 family,
2513 					struct nlattr *nla)
2514 {
2515 	if (nft_request_module(net, "nft-expr-%u-%.*s", family,
2516 			       nla_len(nla), (char *)nla_data(nla)) == -EAGAIN)
2517 		return -EAGAIN;
2518 
2519 	return 0;
2520 }
2521 #endif
2522 
nft_expr_type_get(struct net * net,u8 family,struct nlattr * nla)2523 static const struct nft_expr_type *nft_expr_type_get(struct net *net,
2524 						     u8 family,
2525 						     struct nlattr *nla)
2526 {
2527 	const struct nft_expr_type *type;
2528 
2529 	if (nla == NULL)
2530 		return ERR_PTR(-EINVAL);
2531 
2532 	type = __nft_expr_type_get(family, nla);
2533 	if (type != NULL && try_module_get(type->owner))
2534 		return type;
2535 
2536 	lockdep_nfnl_nft_mutex_not_held();
2537 #ifdef CONFIG_MODULES
2538 	if (type == NULL) {
2539 		if (nft_expr_type_request_module(net, family, nla) == -EAGAIN)
2540 			return ERR_PTR(-EAGAIN);
2541 
2542 		if (nft_request_module(net, "nft-expr-%.*s",
2543 				       nla_len(nla),
2544 				       (char *)nla_data(nla)) == -EAGAIN)
2545 			return ERR_PTR(-EAGAIN);
2546 	}
2547 #endif
2548 	return ERR_PTR(-ENOENT);
2549 }
2550 
2551 static const struct nla_policy nft_expr_policy[NFTA_EXPR_MAX + 1] = {
2552 	[NFTA_EXPR_NAME]	= { .type = NLA_STRING,
2553 				    .len = NFT_MODULE_AUTOLOAD_LIMIT },
2554 	[NFTA_EXPR_DATA]	= { .type = NLA_NESTED },
2555 };
2556 
nf_tables_fill_expr_info(struct sk_buff * skb,const struct nft_expr * expr)2557 static int nf_tables_fill_expr_info(struct sk_buff *skb,
2558 				    const struct nft_expr *expr)
2559 {
2560 	if (nla_put_string(skb, NFTA_EXPR_NAME, expr->ops->type->name))
2561 		goto nla_put_failure;
2562 
2563 	if (expr->ops->dump) {
2564 		struct nlattr *data = nla_nest_start_noflag(skb,
2565 							    NFTA_EXPR_DATA);
2566 		if (data == NULL)
2567 			goto nla_put_failure;
2568 		if (expr->ops->dump(skb, expr) < 0)
2569 			goto nla_put_failure;
2570 		nla_nest_end(skb, data);
2571 	}
2572 
2573 	return skb->len;
2574 
2575 nla_put_failure:
2576 	return -1;
2577 };
2578 
nft_expr_dump(struct sk_buff * skb,unsigned int attr,const struct nft_expr * expr)2579 int nft_expr_dump(struct sk_buff *skb, unsigned int attr,
2580 		  const struct nft_expr *expr)
2581 {
2582 	struct nlattr *nest;
2583 
2584 	nest = nla_nest_start_noflag(skb, attr);
2585 	if (!nest)
2586 		goto nla_put_failure;
2587 	if (nf_tables_fill_expr_info(skb, expr) < 0)
2588 		goto nla_put_failure;
2589 	nla_nest_end(skb, nest);
2590 	return 0;
2591 
2592 nla_put_failure:
2593 	return -1;
2594 }
2595 
2596 struct nft_expr_info {
2597 	const struct nft_expr_ops	*ops;
2598 	const struct nlattr		*attr;
2599 	struct nlattr			*tb[NFT_EXPR_MAXATTR + 1];
2600 };
2601 
nf_tables_expr_parse(const struct nft_ctx * ctx,const struct nlattr * nla,struct nft_expr_info * info)2602 static int nf_tables_expr_parse(const struct nft_ctx *ctx,
2603 				const struct nlattr *nla,
2604 				struct nft_expr_info *info)
2605 {
2606 	const struct nft_expr_type *type;
2607 	const struct nft_expr_ops *ops;
2608 	struct nlattr *tb[NFTA_EXPR_MAX + 1];
2609 	int err;
2610 
2611 	err = nla_parse_nested_deprecated(tb, NFTA_EXPR_MAX, nla,
2612 					  nft_expr_policy, NULL);
2613 	if (err < 0)
2614 		return err;
2615 
2616 	type = nft_expr_type_get(ctx->net, ctx->family, tb[NFTA_EXPR_NAME]);
2617 	if (IS_ERR(type))
2618 		return PTR_ERR(type);
2619 
2620 	if (tb[NFTA_EXPR_DATA]) {
2621 		err = nla_parse_nested_deprecated(info->tb, type->maxattr,
2622 						  tb[NFTA_EXPR_DATA],
2623 						  type->policy, NULL);
2624 		if (err < 0)
2625 			goto err1;
2626 	} else
2627 		memset(info->tb, 0, sizeof(info->tb[0]) * (type->maxattr + 1));
2628 
2629 	if (type->select_ops != NULL) {
2630 		ops = type->select_ops(ctx,
2631 				       (const struct nlattr * const *)info->tb);
2632 		if (IS_ERR(ops)) {
2633 			err = PTR_ERR(ops);
2634 #ifdef CONFIG_MODULES
2635 			if (err == -EAGAIN)
2636 				if (nft_expr_type_request_module(ctx->net,
2637 								 ctx->family,
2638 								 tb[NFTA_EXPR_NAME]) != -EAGAIN)
2639 					err = -ENOENT;
2640 #endif
2641 			goto err1;
2642 		}
2643 	} else
2644 		ops = type->ops;
2645 
2646 	info->attr = nla;
2647 	info->ops = ops;
2648 
2649 	return 0;
2650 
2651 err1:
2652 	module_put(type->owner);
2653 	return err;
2654 }
2655 
nf_tables_newexpr(const struct nft_ctx * ctx,const struct nft_expr_info * info,struct nft_expr * expr)2656 static int nf_tables_newexpr(const struct nft_ctx *ctx,
2657 			     const struct nft_expr_info *info,
2658 			     struct nft_expr *expr)
2659 {
2660 	const struct nft_expr_ops *ops = info->ops;
2661 	int err;
2662 
2663 	expr->ops = ops;
2664 	if (ops->init) {
2665 		err = ops->init(ctx, expr, (const struct nlattr **)info->tb);
2666 		if (err < 0)
2667 			goto err1;
2668 	}
2669 
2670 	return 0;
2671 err1:
2672 	expr->ops = NULL;
2673 	return err;
2674 }
2675 
nf_tables_expr_destroy(const struct nft_ctx * ctx,struct nft_expr * expr)2676 static void nf_tables_expr_destroy(const struct nft_ctx *ctx,
2677 				   struct nft_expr *expr)
2678 {
2679 	const struct nft_expr_type *type = expr->ops->type;
2680 
2681 	if (expr->ops->destroy)
2682 		expr->ops->destroy(ctx, expr);
2683 	module_put(type->owner);
2684 }
2685 
nft_expr_init(const struct nft_ctx * ctx,const struct nlattr * nla)2686 static struct nft_expr *nft_expr_init(const struct nft_ctx *ctx,
2687 				      const struct nlattr *nla)
2688 {
2689 	struct nft_expr_info info;
2690 	struct nft_expr *expr;
2691 	struct module *owner;
2692 	int err;
2693 
2694 	err = nf_tables_expr_parse(ctx, nla, &info);
2695 	if (err < 0)
2696 		goto err_expr_parse;
2697 
2698 	err = -EOPNOTSUPP;
2699 	if (!(info.ops->type->flags & NFT_EXPR_STATEFUL))
2700 		goto err_expr_stateful;
2701 
2702 	err = -ENOMEM;
2703 	expr = kzalloc(info.ops->size, GFP_KERNEL);
2704 	if (expr == NULL)
2705 		goto err_expr_stateful;
2706 
2707 	err = nf_tables_newexpr(ctx, &info, expr);
2708 	if (err < 0)
2709 		goto err_expr_new;
2710 
2711 	return expr;
2712 err_expr_new:
2713 	kfree(expr);
2714 err_expr_stateful:
2715 	owner = info.ops->type->owner;
2716 	if (info.ops->type->release_ops)
2717 		info.ops->type->release_ops(info.ops);
2718 
2719 	module_put(owner);
2720 err_expr_parse:
2721 	return ERR_PTR(err);
2722 }
2723 
nft_expr_clone(struct nft_expr * dst,struct nft_expr * src)2724 int nft_expr_clone(struct nft_expr *dst, struct nft_expr *src)
2725 {
2726 	int err;
2727 
2728 	if (src->ops->clone) {
2729 		dst->ops = src->ops;
2730 		err = src->ops->clone(dst, src);
2731 		if (err < 0)
2732 			return err;
2733 	} else {
2734 		memcpy(dst, src, src->ops->size);
2735 	}
2736 
2737 	__module_get(src->ops->type->owner);
2738 
2739 	return 0;
2740 }
2741 
nft_expr_destroy(const struct nft_ctx * ctx,struct nft_expr * expr)2742 void nft_expr_destroy(const struct nft_ctx *ctx, struct nft_expr *expr)
2743 {
2744 	nf_tables_expr_destroy(ctx, expr);
2745 	kfree(expr);
2746 }
2747 
2748 /*
2749  * Rules
2750  */
2751 
__nft_rule_lookup(const struct nft_chain * chain,u64 handle)2752 static struct nft_rule *__nft_rule_lookup(const struct nft_chain *chain,
2753 					  u64 handle)
2754 {
2755 	struct nft_rule *rule;
2756 
2757 	// FIXME: this sucks
2758 	list_for_each_entry_rcu(rule, &chain->rules, list) {
2759 		if (handle == rule->handle)
2760 			return rule;
2761 	}
2762 
2763 	return ERR_PTR(-ENOENT);
2764 }
2765 
nft_rule_lookup(const struct nft_chain * chain,const struct nlattr * nla)2766 static struct nft_rule *nft_rule_lookup(const struct nft_chain *chain,
2767 					const struct nlattr *nla)
2768 {
2769 	if (nla == NULL)
2770 		return ERR_PTR(-EINVAL);
2771 
2772 	return __nft_rule_lookup(chain, be64_to_cpu(nla_get_be64(nla)));
2773 }
2774 
2775 static const struct nla_policy nft_rule_policy[NFTA_RULE_MAX + 1] = {
2776 	[NFTA_RULE_TABLE]	= { .type = NLA_STRING,
2777 				    .len = NFT_TABLE_MAXNAMELEN - 1 },
2778 	[NFTA_RULE_CHAIN]	= { .type = NLA_STRING,
2779 				    .len = NFT_CHAIN_MAXNAMELEN - 1 },
2780 	[NFTA_RULE_HANDLE]	= { .type = NLA_U64 },
2781 	[NFTA_RULE_EXPRESSIONS]	= { .type = NLA_NESTED },
2782 	[NFTA_RULE_COMPAT]	= { .type = NLA_NESTED },
2783 	[NFTA_RULE_POSITION]	= { .type = NLA_U64 },
2784 	[NFTA_RULE_USERDATA]	= { .type = NLA_BINARY,
2785 				    .len = NFT_USERDATA_MAXLEN },
2786 	[NFTA_RULE_ID]		= { .type = NLA_U32 },
2787 	[NFTA_RULE_POSITION_ID]	= { .type = NLA_U32 },
2788 	[NFTA_RULE_CHAIN_ID]	= { .type = NLA_U32 },
2789 };
2790 
nf_tables_fill_rule_info(struct sk_buff * skb,struct net * net,u32 portid,u32 seq,int event,u32 flags,int family,const struct nft_table * table,const struct nft_chain * chain,const struct nft_rule * rule,const struct nft_rule * prule)2791 static int nf_tables_fill_rule_info(struct sk_buff *skb, struct net *net,
2792 				    u32 portid, u32 seq, int event,
2793 				    u32 flags, int family,
2794 				    const struct nft_table *table,
2795 				    const struct nft_chain *chain,
2796 				    const struct nft_rule *rule,
2797 				    const struct nft_rule *prule)
2798 {
2799 	struct nlmsghdr *nlh;
2800 	const struct nft_expr *expr, *next;
2801 	struct nlattr *list;
2802 	u16 type = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
2803 
2804 	nlh = nfnl_msg_put(skb, portid, seq, type, flags, family, NFNETLINK_V0,
2805 			   nft_base_seq(net));
2806 	if (!nlh)
2807 		goto nla_put_failure;
2808 
2809 	if (nla_put_string(skb, NFTA_RULE_TABLE, table->name))
2810 		goto nla_put_failure;
2811 	if (nla_put_string(skb, NFTA_RULE_CHAIN, chain->name))
2812 		goto nla_put_failure;
2813 	if (nla_put_be64(skb, NFTA_RULE_HANDLE, cpu_to_be64(rule->handle),
2814 			 NFTA_RULE_PAD))
2815 		goto nla_put_failure;
2816 
2817 	if (event != NFT_MSG_DELRULE && prule) {
2818 		if (nla_put_be64(skb, NFTA_RULE_POSITION,
2819 				 cpu_to_be64(prule->handle),
2820 				 NFTA_RULE_PAD))
2821 			goto nla_put_failure;
2822 	}
2823 
2824 	list = nla_nest_start_noflag(skb, NFTA_RULE_EXPRESSIONS);
2825 	if (list == NULL)
2826 		goto nla_put_failure;
2827 	nft_rule_for_each_expr(expr, next, rule) {
2828 		if (nft_expr_dump(skb, NFTA_LIST_ELEM, expr) < 0)
2829 			goto nla_put_failure;
2830 	}
2831 	nla_nest_end(skb, list);
2832 
2833 	if (rule->udata) {
2834 		struct nft_userdata *udata = nft_userdata(rule);
2835 		if (nla_put(skb, NFTA_RULE_USERDATA, udata->len + 1,
2836 			    udata->data) < 0)
2837 			goto nla_put_failure;
2838 	}
2839 
2840 	nlmsg_end(skb, nlh);
2841 	return 0;
2842 
2843 nla_put_failure:
2844 	nlmsg_trim(skb, nlh);
2845 	return -1;
2846 }
2847 
nf_tables_rule_notify(const struct nft_ctx * ctx,const struct nft_rule * rule,int event)2848 static void nf_tables_rule_notify(const struct nft_ctx *ctx,
2849 				  const struct nft_rule *rule, int event)
2850 {
2851 	struct sk_buff *skb;
2852 	int err;
2853 
2854 	if (!ctx->report &&
2855 	    !nfnetlink_has_listeners(ctx->net, NFNLGRP_NFTABLES))
2856 		return;
2857 
2858 	skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2859 	if (skb == NULL)
2860 		goto err;
2861 
2862 	err = nf_tables_fill_rule_info(skb, ctx->net, ctx->portid, ctx->seq,
2863 				       event, 0, ctx->family, ctx->table,
2864 				       ctx->chain, rule, NULL);
2865 	if (err < 0) {
2866 		kfree_skb(skb);
2867 		goto err;
2868 	}
2869 
2870 	nft_notify_enqueue(skb, ctx->report, &ctx->net->nft.notify_list);
2871 	return;
2872 err:
2873 	nfnetlink_set_err(ctx->net, ctx->portid, NFNLGRP_NFTABLES, -ENOBUFS);
2874 }
2875 
2876 struct nft_rule_dump_ctx {
2877 	char *table;
2878 	char *chain;
2879 };
2880 
__nf_tables_dump_rules(struct sk_buff * skb,unsigned int * idx,struct netlink_callback * cb,const struct nft_table * table,const struct nft_chain * chain)2881 static int __nf_tables_dump_rules(struct sk_buff *skb,
2882 				  unsigned int *idx,
2883 				  struct netlink_callback *cb,
2884 				  const struct nft_table *table,
2885 				  const struct nft_chain *chain)
2886 {
2887 	struct net *net = sock_net(skb->sk);
2888 	const struct nft_rule *rule, *prule;
2889 	unsigned int s_idx = cb->args[0];
2890 
2891 	prule = NULL;
2892 	list_for_each_entry_rcu(rule, &chain->rules, list) {
2893 		if (!nft_is_active(net, rule))
2894 			goto cont_skip;
2895 		if (*idx < s_idx)
2896 			goto cont;
2897 		if (*idx > s_idx) {
2898 			memset(&cb->args[1], 0,
2899 					sizeof(cb->args) - sizeof(cb->args[0]));
2900 		}
2901 		if (nf_tables_fill_rule_info(skb, net, NETLINK_CB(cb->skb).portid,
2902 					cb->nlh->nlmsg_seq,
2903 					NFT_MSG_NEWRULE,
2904 					NLM_F_MULTI | NLM_F_APPEND,
2905 					table->family,
2906 					table, chain, rule, prule) < 0)
2907 			return 1;
2908 
2909 		nl_dump_check_consistent(cb, nlmsg_hdr(skb));
2910 cont:
2911 		prule = rule;
2912 cont_skip:
2913 		(*idx)++;
2914 	}
2915 	return 0;
2916 }
2917 
nf_tables_dump_rules(struct sk_buff * skb,struct netlink_callback * cb)2918 static int nf_tables_dump_rules(struct sk_buff *skb,
2919 				struct netlink_callback *cb)
2920 {
2921 	const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
2922 	const struct nft_rule_dump_ctx *ctx = cb->data;
2923 	struct nft_table *table;
2924 	const struct nft_chain *chain;
2925 	unsigned int idx = 0;
2926 	struct net *net = sock_net(skb->sk);
2927 	int family = nfmsg->nfgen_family;
2928 
2929 	rcu_read_lock();
2930 	cb->seq = net->nft.base_seq;
2931 
2932 	list_for_each_entry_rcu(table, &net->nft.tables, list) {
2933 		if (family != NFPROTO_UNSPEC && family != table->family)
2934 			continue;
2935 
2936 		if (ctx && ctx->table && strcmp(ctx->table, table->name) != 0)
2937 			continue;
2938 
2939 		if (ctx && ctx->table && ctx->chain) {
2940 			struct rhlist_head *list, *tmp;
2941 
2942 			list = rhltable_lookup(&table->chains_ht, ctx->chain,
2943 					       nft_chain_ht_params);
2944 			if (!list)
2945 				goto done;
2946 
2947 			rhl_for_each_entry_rcu(chain, tmp, list, rhlhead) {
2948 				if (!nft_is_active(net, chain))
2949 					continue;
2950 				__nf_tables_dump_rules(skb, &idx,
2951 						       cb, table, chain);
2952 				break;
2953 			}
2954 			goto done;
2955 		}
2956 
2957 		list_for_each_entry_rcu(chain, &table->chains, list) {
2958 			if (__nf_tables_dump_rules(skb, &idx, cb, table, chain))
2959 				goto done;
2960 		}
2961 
2962 		if (ctx && ctx->table)
2963 			break;
2964 	}
2965 done:
2966 	rcu_read_unlock();
2967 
2968 	cb->args[0] = idx;
2969 	return skb->len;
2970 }
2971 
nf_tables_dump_rules_start(struct netlink_callback * cb)2972 static int nf_tables_dump_rules_start(struct netlink_callback *cb)
2973 {
2974 	const struct nlattr * const *nla = cb->data;
2975 	struct nft_rule_dump_ctx *ctx = NULL;
2976 
2977 	if (nla[NFTA_RULE_TABLE] || nla[NFTA_RULE_CHAIN]) {
2978 		ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
2979 		if (!ctx)
2980 			return -ENOMEM;
2981 
2982 		if (nla[NFTA_RULE_TABLE]) {
2983 			ctx->table = nla_strdup(nla[NFTA_RULE_TABLE],
2984 							GFP_ATOMIC);
2985 			if (!ctx->table) {
2986 				kfree(ctx);
2987 				return -ENOMEM;
2988 			}
2989 		}
2990 		if (nla[NFTA_RULE_CHAIN]) {
2991 			ctx->chain = nla_strdup(nla[NFTA_RULE_CHAIN],
2992 						GFP_ATOMIC);
2993 			if (!ctx->chain) {
2994 				kfree(ctx->table);
2995 				kfree(ctx);
2996 				return -ENOMEM;
2997 			}
2998 		}
2999 	}
3000 
3001 	cb->data = ctx;
3002 	return 0;
3003 }
3004 
nf_tables_dump_rules_done(struct netlink_callback * cb)3005 static int nf_tables_dump_rules_done(struct netlink_callback *cb)
3006 {
3007 	struct nft_rule_dump_ctx *ctx = cb->data;
3008 
3009 	if (ctx) {
3010 		kfree(ctx->table);
3011 		kfree(ctx->chain);
3012 		kfree(ctx);
3013 	}
3014 	return 0;
3015 }
3016 
3017 /* called with rcu_read_lock held */
nf_tables_getrule(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)3018 static int nf_tables_getrule(struct net *net, struct sock *nlsk,
3019 			     struct sk_buff *skb, const struct nlmsghdr *nlh,
3020 			     const struct nlattr * const nla[],
3021 			     struct netlink_ext_ack *extack)
3022 {
3023 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3024 	u8 genmask = nft_genmask_cur(net);
3025 	const struct nft_chain *chain;
3026 	const struct nft_rule *rule;
3027 	struct nft_table *table;
3028 	struct sk_buff *skb2;
3029 	int family = nfmsg->nfgen_family;
3030 	int err;
3031 
3032 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
3033 		struct netlink_dump_control c = {
3034 			.start= nf_tables_dump_rules_start,
3035 			.dump = nf_tables_dump_rules,
3036 			.done = nf_tables_dump_rules_done,
3037 			.module = THIS_MODULE,
3038 			.data = (void *)nla,
3039 		};
3040 
3041 		return nft_netlink_dump_start_rcu(nlsk, skb, nlh, &c);
3042 	}
3043 
3044 	table = nft_table_lookup(net, nla[NFTA_RULE_TABLE], family, genmask);
3045 	if (IS_ERR(table)) {
3046 		NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_TABLE]);
3047 		return PTR_ERR(table);
3048 	}
3049 
3050 	chain = nft_chain_lookup(net, table, nla[NFTA_RULE_CHAIN], genmask);
3051 	if (IS_ERR(chain)) {
3052 		NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
3053 		return PTR_ERR(chain);
3054 	}
3055 
3056 	rule = nft_rule_lookup(chain, nla[NFTA_RULE_HANDLE]);
3057 	if (IS_ERR(rule)) {
3058 		NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_HANDLE]);
3059 		return PTR_ERR(rule);
3060 	}
3061 
3062 	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
3063 	if (!skb2)
3064 		return -ENOMEM;
3065 
3066 	err = nf_tables_fill_rule_info(skb2, net, NETLINK_CB(skb).portid,
3067 				       nlh->nlmsg_seq, NFT_MSG_NEWRULE, 0,
3068 				       family, table, chain, rule, NULL);
3069 	if (err < 0)
3070 		goto err_fill_rule_info;
3071 
3072 	return nfnetlink_unicast(skb2, net, NETLINK_CB(skb).portid);
3073 
3074 err_fill_rule_info:
3075 	kfree_skb(skb2);
3076 	return err;
3077 }
3078 
nf_tables_rule_destroy(const struct nft_ctx * ctx,struct nft_rule * rule)3079 static void nf_tables_rule_destroy(const struct nft_ctx *ctx,
3080 				   struct nft_rule *rule)
3081 {
3082 	struct nft_expr *expr, *next;
3083 
3084 	/*
3085 	 * Careful: some expressions might not be initialized in case this
3086 	 * is called on error from nf_tables_newrule().
3087 	 */
3088 	expr = nft_expr_first(rule);
3089 	while (nft_expr_more(rule, expr)) {
3090 		next = nft_expr_next(expr);
3091 		nf_tables_expr_destroy(ctx, expr);
3092 		expr = next;
3093 	}
3094 	kfree(rule);
3095 }
3096 
nf_tables_rule_release(const struct nft_ctx * ctx,struct nft_rule * rule)3097 void nf_tables_rule_release(const struct nft_ctx *ctx, struct nft_rule *rule)
3098 {
3099 	nft_rule_expr_deactivate(ctx, rule, NFT_TRANS_RELEASE);
3100 	nf_tables_rule_destroy(ctx, rule);
3101 }
3102 
nft_chain_validate(const struct nft_ctx * ctx,const struct nft_chain * chain)3103 int nft_chain_validate(const struct nft_ctx *ctx, const struct nft_chain *chain)
3104 {
3105 	struct nft_expr *expr, *last;
3106 	const struct nft_data *data;
3107 	struct nft_rule *rule;
3108 	int err;
3109 
3110 	if (ctx->level == NFT_JUMP_STACK_SIZE)
3111 		return -EMLINK;
3112 
3113 	list_for_each_entry(rule, &chain->rules, list) {
3114 		if (!nft_is_active_next(ctx->net, rule))
3115 			continue;
3116 
3117 		nft_rule_for_each_expr(expr, last, rule) {
3118 			if (!expr->ops->validate)
3119 				continue;
3120 
3121 			err = expr->ops->validate(ctx, expr, &data);
3122 			if (err < 0)
3123 				return err;
3124 		}
3125 	}
3126 
3127 	return 0;
3128 }
3129 EXPORT_SYMBOL_GPL(nft_chain_validate);
3130 
nft_table_validate(struct net * net,const struct nft_table * table)3131 static int nft_table_validate(struct net *net, const struct nft_table *table)
3132 {
3133 	struct nft_chain *chain;
3134 	struct nft_ctx ctx = {
3135 		.net	= net,
3136 		.family	= table->family,
3137 	};
3138 	int err;
3139 
3140 	list_for_each_entry(chain, &table->chains, list) {
3141 		if (!nft_is_base_chain(chain))
3142 			continue;
3143 
3144 		ctx.chain = chain;
3145 		err = nft_chain_validate(&ctx, chain);
3146 		if (err < 0)
3147 			return err;
3148 	}
3149 
3150 	return 0;
3151 }
3152 
3153 static struct nft_rule *nft_rule_lookup_byid(const struct net *net,
3154 					     const struct nft_chain *chain,
3155 					     const struct nlattr *nla);
3156 
3157 #define NFT_RULE_MAXEXPRS	128
3158 
nf_tables_newrule(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)3159 static int nf_tables_newrule(struct net *net, struct sock *nlsk,
3160 			     struct sk_buff *skb, const struct nlmsghdr *nlh,
3161 			     const struct nlattr * const nla[],
3162 			     struct netlink_ext_ack *extack)
3163 {
3164 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3165 	u8 genmask = nft_genmask_next(net);
3166 	struct nft_expr_info *info = NULL;
3167 	int family = nfmsg->nfgen_family;
3168 	struct nft_flow_rule *flow;
3169 	struct nft_table *table;
3170 	struct nft_chain *chain;
3171 	struct nft_rule *rule, *old_rule = NULL;
3172 	struct nft_userdata *udata;
3173 	struct nft_trans *trans = NULL;
3174 	struct nft_expr *expr;
3175 	struct nft_ctx ctx;
3176 	struct nlattr *tmp;
3177 	unsigned int size, i, n, ulen = 0, usize = 0;
3178 	int err, rem;
3179 	u64 handle, pos_handle;
3180 
3181 	lockdep_assert_held(&net->nft.commit_mutex);
3182 
3183 	table = nft_table_lookup(net, nla[NFTA_RULE_TABLE], family, genmask);
3184 	if (IS_ERR(table)) {
3185 		NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_TABLE]);
3186 		return PTR_ERR(table);
3187 	}
3188 
3189 	if (nla[NFTA_RULE_CHAIN]) {
3190 		chain = nft_chain_lookup(net, table, nla[NFTA_RULE_CHAIN],
3191 					 genmask);
3192 		if (IS_ERR(chain)) {
3193 			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
3194 			return PTR_ERR(chain);
3195 		}
3196 		if (nft_chain_is_bound(chain))
3197 			return -EOPNOTSUPP;
3198 
3199 	} else if (nla[NFTA_RULE_CHAIN_ID]) {
3200 		chain = nft_chain_lookup_byid(net, table, nla[NFTA_RULE_CHAIN_ID]);
3201 		if (IS_ERR(chain)) {
3202 			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN_ID]);
3203 			return PTR_ERR(chain);
3204 		}
3205 	} else {
3206 		return -EINVAL;
3207 	}
3208 
3209 	if (nla[NFTA_RULE_HANDLE]) {
3210 		handle = be64_to_cpu(nla_get_be64(nla[NFTA_RULE_HANDLE]));
3211 		rule = __nft_rule_lookup(chain, handle);
3212 		if (IS_ERR(rule)) {
3213 			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_HANDLE]);
3214 			return PTR_ERR(rule);
3215 		}
3216 
3217 		if (nlh->nlmsg_flags & NLM_F_EXCL) {
3218 			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_HANDLE]);
3219 			return -EEXIST;
3220 		}
3221 		if (nlh->nlmsg_flags & NLM_F_REPLACE)
3222 			old_rule = rule;
3223 		else
3224 			return -EOPNOTSUPP;
3225 	} else {
3226 		if (!(nlh->nlmsg_flags & NLM_F_CREATE) ||
3227 		    nlh->nlmsg_flags & NLM_F_REPLACE)
3228 			return -EINVAL;
3229 		handle = nf_tables_alloc_handle(table);
3230 
3231 		if (chain->use == UINT_MAX)
3232 			return -EOVERFLOW;
3233 
3234 		if (nla[NFTA_RULE_POSITION]) {
3235 			pos_handle = be64_to_cpu(nla_get_be64(nla[NFTA_RULE_POSITION]));
3236 			old_rule = __nft_rule_lookup(chain, pos_handle);
3237 			if (IS_ERR(old_rule)) {
3238 				NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_POSITION]);
3239 				return PTR_ERR(old_rule);
3240 			}
3241 		} else if (nla[NFTA_RULE_POSITION_ID]) {
3242 			old_rule = nft_rule_lookup_byid(net, chain, nla[NFTA_RULE_POSITION_ID]);
3243 			if (IS_ERR(old_rule)) {
3244 				NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_POSITION_ID]);
3245 				return PTR_ERR(old_rule);
3246 			}
3247 		}
3248 	}
3249 
3250 	nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
3251 
3252 	n = 0;
3253 	size = 0;
3254 	if (nla[NFTA_RULE_EXPRESSIONS]) {
3255 		info = kvmalloc_array(NFT_RULE_MAXEXPRS,
3256 				      sizeof(struct nft_expr_info),
3257 				      GFP_KERNEL);
3258 		if (!info)
3259 			return -ENOMEM;
3260 
3261 		nla_for_each_nested(tmp, nla[NFTA_RULE_EXPRESSIONS], rem) {
3262 			err = -EINVAL;
3263 			if (nla_type(tmp) != NFTA_LIST_ELEM)
3264 				goto err1;
3265 			if (n == NFT_RULE_MAXEXPRS)
3266 				goto err1;
3267 			err = nf_tables_expr_parse(&ctx, tmp, &info[n]);
3268 			if (err < 0) {
3269 				NL_SET_BAD_ATTR(extack, tmp);
3270 				goto err1;
3271 			}
3272 			size += info[n].ops->size;
3273 			n++;
3274 		}
3275 	}
3276 	/* Check for overflow of dlen field */
3277 	err = -EFBIG;
3278 	if (size >= 1 << 12)
3279 		goto err1;
3280 
3281 	if (nla[NFTA_RULE_USERDATA]) {
3282 		ulen = nla_len(nla[NFTA_RULE_USERDATA]);
3283 		if (ulen > 0)
3284 			usize = sizeof(struct nft_userdata) + ulen;
3285 	}
3286 
3287 	err = -ENOMEM;
3288 	rule = kzalloc(sizeof(*rule) + size + usize, GFP_KERNEL);
3289 	if (rule == NULL)
3290 		goto err1;
3291 
3292 	nft_activate_next(net, rule);
3293 
3294 	rule->handle = handle;
3295 	rule->dlen   = size;
3296 	rule->udata  = ulen ? 1 : 0;
3297 
3298 	if (ulen) {
3299 		udata = nft_userdata(rule);
3300 		udata->len = ulen - 1;
3301 		nla_memcpy(udata->data, nla[NFTA_RULE_USERDATA], ulen);
3302 	}
3303 
3304 	expr = nft_expr_first(rule);
3305 	for (i = 0; i < n; i++) {
3306 		err = nf_tables_newexpr(&ctx, &info[i], expr);
3307 		if (err < 0) {
3308 			NL_SET_BAD_ATTR(extack, info[i].attr);
3309 			goto err2;
3310 		}
3311 
3312 		if (info[i].ops->validate)
3313 			nft_validate_state_update(net, NFT_VALIDATE_NEED);
3314 
3315 		info[i].ops = NULL;
3316 		expr = nft_expr_next(expr);
3317 	}
3318 
3319 	if (nlh->nlmsg_flags & NLM_F_REPLACE) {
3320 		trans = nft_trans_rule_add(&ctx, NFT_MSG_NEWRULE, rule);
3321 		if (trans == NULL) {
3322 			err = -ENOMEM;
3323 			goto err2;
3324 		}
3325 		err = nft_delrule(&ctx, old_rule);
3326 		if (err < 0) {
3327 			nft_trans_destroy(trans);
3328 			goto err2;
3329 		}
3330 
3331 		list_add_tail_rcu(&rule->list, &old_rule->list);
3332 	} else {
3333 		trans = nft_trans_rule_add(&ctx, NFT_MSG_NEWRULE, rule);
3334 		if (!trans) {
3335 			err = -ENOMEM;
3336 			goto err2;
3337 		}
3338 
3339 		if (nlh->nlmsg_flags & NLM_F_APPEND) {
3340 			if (old_rule)
3341 				list_add_rcu(&rule->list, &old_rule->list);
3342 			else
3343 				list_add_tail_rcu(&rule->list, &chain->rules);
3344 		 } else {
3345 			if (old_rule)
3346 				list_add_tail_rcu(&rule->list, &old_rule->list);
3347 			else
3348 				list_add_rcu(&rule->list, &chain->rules);
3349 		}
3350 	}
3351 	kvfree(info);
3352 	chain->use++;
3353 
3354 	if (net->nft.validate_state == NFT_VALIDATE_DO)
3355 		return nft_table_validate(net, table);
3356 
3357 	if (chain->flags & NFT_CHAIN_HW_OFFLOAD) {
3358 		flow = nft_flow_rule_create(net, rule);
3359 		if (IS_ERR(flow))
3360 			return PTR_ERR(flow);
3361 
3362 		nft_trans_flow_rule(trans) = flow;
3363 	}
3364 
3365 	return 0;
3366 err2:
3367 	nf_tables_rule_release(&ctx, rule);
3368 err1:
3369 	for (i = 0; i < n; i++) {
3370 		if (info[i].ops) {
3371 			module_put(info[i].ops->type->owner);
3372 			if (info[i].ops->type->release_ops)
3373 				info[i].ops->type->release_ops(info[i].ops);
3374 		}
3375 	}
3376 	kvfree(info);
3377 	return err;
3378 }
3379 
nft_rule_lookup_byid(const struct net * net,const struct nft_chain * chain,const struct nlattr * nla)3380 static struct nft_rule *nft_rule_lookup_byid(const struct net *net,
3381 					     const struct nft_chain *chain,
3382 					     const struct nlattr *nla)
3383 {
3384 	u32 id = ntohl(nla_get_be32(nla));
3385 	struct nft_trans *trans;
3386 
3387 	list_for_each_entry(trans, &net->nft.commit_list, list) {
3388 		struct nft_rule *rule = nft_trans_rule(trans);
3389 
3390 		if (trans->msg_type == NFT_MSG_NEWRULE &&
3391 		    trans->ctx.chain == chain &&
3392 		    id == nft_trans_rule_id(trans))
3393 			return rule;
3394 	}
3395 	return ERR_PTR(-ENOENT);
3396 }
3397 
nf_tables_delrule(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)3398 static int nf_tables_delrule(struct net *net, struct sock *nlsk,
3399 			     struct sk_buff *skb, const struct nlmsghdr *nlh,
3400 			     const struct nlattr * const nla[],
3401 			     struct netlink_ext_ack *extack)
3402 {
3403 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3404 	u8 genmask = nft_genmask_next(net);
3405 	struct nft_table *table;
3406 	struct nft_chain *chain = NULL;
3407 	struct nft_rule *rule;
3408 	int family = nfmsg->nfgen_family, err = 0;
3409 	struct nft_ctx ctx;
3410 
3411 	table = nft_table_lookup(net, nla[NFTA_RULE_TABLE], family, genmask);
3412 	if (IS_ERR(table)) {
3413 		NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_TABLE]);
3414 		return PTR_ERR(table);
3415 	}
3416 
3417 	if (nla[NFTA_RULE_CHAIN]) {
3418 		chain = nft_chain_lookup(net, table, nla[NFTA_RULE_CHAIN],
3419 					 genmask);
3420 		if (IS_ERR(chain)) {
3421 			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
3422 			return PTR_ERR(chain);
3423 		}
3424 		if (nft_chain_is_bound(chain))
3425 			return -EOPNOTSUPP;
3426 	}
3427 
3428 	nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
3429 
3430 	if (chain) {
3431 		if (nla[NFTA_RULE_HANDLE]) {
3432 			rule = nft_rule_lookup(chain, nla[NFTA_RULE_HANDLE]);
3433 			if (IS_ERR(rule)) {
3434 				NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_HANDLE]);
3435 				return PTR_ERR(rule);
3436 			}
3437 
3438 			err = nft_delrule(&ctx, rule);
3439 		} else if (nla[NFTA_RULE_ID]) {
3440 			rule = nft_rule_lookup_byid(net, chain, nla[NFTA_RULE_ID]);
3441 			if (IS_ERR(rule)) {
3442 				NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_ID]);
3443 				return PTR_ERR(rule);
3444 			}
3445 
3446 			err = nft_delrule(&ctx, rule);
3447 		} else {
3448 			err = nft_delrule_by_chain(&ctx);
3449 		}
3450 	} else {
3451 		list_for_each_entry(chain, &table->chains, list) {
3452 			if (!nft_is_active_next(net, chain))
3453 				continue;
3454 
3455 			ctx.chain = chain;
3456 			err = nft_delrule_by_chain(&ctx);
3457 			if (err < 0)
3458 				break;
3459 		}
3460 	}
3461 
3462 	return err;
3463 }
3464 
3465 /*
3466  * Sets
3467  */
3468 static const struct nft_set_type *nft_set_types[] = {
3469 	&nft_set_hash_fast_type,
3470 	&nft_set_hash_type,
3471 	&nft_set_rhash_type,
3472 	&nft_set_bitmap_type,
3473 	&nft_set_rbtree_type,
3474 #if defined(CONFIG_X86_64) && !defined(CONFIG_UML)
3475 	&nft_set_pipapo_avx2_type,
3476 #endif
3477 	&nft_set_pipapo_type,
3478 };
3479 
3480 #define NFT_SET_FEATURES	(NFT_SET_INTERVAL | NFT_SET_MAP | \
3481 				 NFT_SET_TIMEOUT | NFT_SET_OBJECT | \
3482 				 NFT_SET_EVAL)
3483 
nft_set_ops_candidate(const struct nft_set_type * type,u32 flags)3484 static bool nft_set_ops_candidate(const struct nft_set_type *type, u32 flags)
3485 {
3486 	return (flags & type->features) == (flags & NFT_SET_FEATURES);
3487 }
3488 
3489 /*
3490  * Select a set implementation based on the data characteristics and the
3491  * given policy. The total memory use might not be known if no size is
3492  * given, in that case the amount of memory per element is used.
3493  */
3494 static const struct nft_set_ops *
nft_select_set_ops(const struct nft_ctx * ctx,const struct nlattr * const nla[],const struct nft_set_desc * desc,enum nft_set_policies policy)3495 nft_select_set_ops(const struct nft_ctx *ctx,
3496 		   const struct nlattr * const nla[],
3497 		   const struct nft_set_desc *desc,
3498 		   enum nft_set_policies policy)
3499 {
3500 	const struct nft_set_ops *ops, *bops;
3501 	struct nft_set_estimate est, best;
3502 	const struct nft_set_type *type;
3503 	u32 flags = 0;
3504 	int i;
3505 
3506 	lockdep_assert_held(&ctx->net->nft.commit_mutex);
3507 	lockdep_nfnl_nft_mutex_not_held();
3508 
3509 	if (nla[NFTA_SET_FLAGS] != NULL)
3510 		flags = ntohl(nla_get_be32(nla[NFTA_SET_FLAGS]));
3511 
3512 	bops	    = NULL;
3513 	best.size   = ~0;
3514 	best.lookup = ~0;
3515 	best.space  = ~0;
3516 
3517 	for (i = 0; i < ARRAY_SIZE(nft_set_types); i++) {
3518 		type = nft_set_types[i];
3519 		ops = &type->ops;
3520 
3521 		if (!nft_set_ops_candidate(type, flags))
3522 			continue;
3523 		if (!ops->estimate(desc, flags, &est))
3524 			continue;
3525 
3526 		switch (policy) {
3527 		case NFT_SET_POL_PERFORMANCE:
3528 			if (est.lookup < best.lookup)
3529 				break;
3530 			if (est.lookup == best.lookup &&
3531 			    est.space < best.space)
3532 				break;
3533 			continue;
3534 		case NFT_SET_POL_MEMORY:
3535 			if (!desc->size) {
3536 				if (est.space < best.space)
3537 					break;
3538 				if (est.space == best.space &&
3539 				    est.lookup < best.lookup)
3540 					break;
3541 			} else if (est.size < best.size || !bops) {
3542 				break;
3543 			}
3544 			continue;
3545 		default:
3546 			break;
3547 		}
3548 
3549 		bops = ops;
3550 		best = est;
3551 	}
3552 
3553 	if (bops != NULL)
3554 		return bops;
3555 
3556 	return ERR_PTR(-EOPNOTSUPP);
3557 }
3558 
3559 static const struct nla_policy nft_set_policy[NFTA_SET_MAX + 1] = {
3560 	[NFTA_SET_TABLE]		= { .type = NLA_STRING,
3561 					    .len = NFT_TABLE_MAXNAMELEN - 1 },
3562 	[NFTA_SET_NAME]			= { .type = NLA_STRING,
3563 					    .len = NFT_SET_MAXNAMELEN - 1 },
3564 	[NFTA_SET_FLAGS]		= { .type = NLA_U32 },
3565 	[NFTA_SET_KEY_TYPE]		= { .type = NLA_U32 },
3566 	[NFTA_SET_KEY_LEN]		= { .type = NLA_U32 },
3567 	[NFTA_SET_DATA_TYPE]		= { .type = NLA_U32 },
3568 	[NFTA_SET_DATA_LEN]		= { .type = NLA_U32 },
3569 	[NFTA_SET_POLICY]		= { .type = NLA_U32 },
3570 	[NFTA_SET_DESC]			= { .type = NLA_NESTED },
3571 	[NFTA_SET_ID]			= { .type = NLA_U32 },
3572 	[NFTA_SET_TIMEOUT]		= { .type = NLA_U64 },
3573 	[NFTA_SET_GC_INTERVAL]		= { .type = NLA_U32 },
3574 	[NFTA_SET_USERDATA]		= { .type = NLA_BINARY,
3575 					    .len  = NFT_USERDATA_MAXLEN },
3576 	[NFTA_SET_OBJ_TYPE]		= { .type = NLA_U32 },
3577 	[NFTA_SET_HANDLE]		= { .type = NLA_U64 },
3578 	[NFTA_SET_EXPR]			= { .type = NLA_NESTED },
3579 };
3580 
3581 static const struct nla_policy nft_set_desc_policy[NFTA_SET_DESC_MAX + 1] = {
3582 	[NFTA_SET_DESC_SIZE]		= { .type = NLA_U32 },
3583 	[NFTA_SET_DESC_CONCAT]		= { .type = NLA_NESTED },
3584 };
3585 
nft_ctx_init_from_setattr(struct nft_ctx * ctx,struct net * net,const struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack,u8 genmask)3586 static int nft_ctx_init_from_setattr(struct nft_ctx *ctx, struct net *net,
3587 				     const struct sk_buff *skb,
3588 				     const struct nlmsghdr *nlh,
3589 				     const struct nlattr * const nla[],
3590 				     struct netlink_ext_ack *extack,
3591 				     u8 genmask)
3592 {
3593 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3594 	int family = nfmsg->nfgen_family;
3595 	struct nft_table *table = NULL;
3596 
3597 	if (nla[NFTA_SET_TABLE] != NULL) {
3598 		table = nft_table_lookup(net, nla[NFTA_SET_TABLE], family,
3599 					 genmask);
3600 		if (IS_ERR(table)) {
3601 			NL_SET_BAD_ATTR(extack, nla[NFTA_SET_TABLE]);
3602 			return PTR_ERR(table);
3603 		}
3604 	}
3605 
3606 	nft_ctx_init(ctx, net, skb, nlh, family, table, NULL, nla);
3607 	return 0;
3608 }
3609 
nft_set_lookup(const struct nft_table * table,const struct nlattr * nla,u8 genmask)3610 static struct nft_set *nft_set_lookup(const struct nft_table *table,
3611 				      const struct nlattr *nla, u8 genmask)
3612 {
3613 	struct nft_set *set;
3614 
3615 	if (nla == NULL)
3616 		return ERR_PTR(-EINVAL);
3617 
3618 	list_for_each_entry_rcu(set, &table->sets, list) {
3619 		if (!nla_strcmp(nla, set->name) &&
3620 		    nft_active_genmask(set, genmask))
3621 			return set;
3622 	}
3623 	return ERR_PTR(-ENOENT);
3624 }
3625 
nft_set_lookup_byhandle(const struct nft_table * table,const struct nlattr * nla,u8 genmask)3626 static struct nft_set *nft_set_lookup_byhandle(const struct nft_table *table,
3627 					       const struct nlattr *nla,
3628 					       u8 genmask)
3629 {
3630 	struct nft_set *set;
3631 
3632 	list_for_each_entry(set, &table->sets, list) {
3633 		if (be64_to_cpu(nla_get_be64(nla)) == set->handle &&
3634 		    nft_active_genmask(set, genmask))
3635 			return set;
3636 	}
3637 	return ERR_PTR(-ENOENT);
3638 }
3639 
nft_set_lookup_byid(const struct net * net,const struct nft_table * table,const struct nlattr * nla,u8 genmask)3640 static struct nft_set *nft_set_lookup_byid(const struct net *net,
3641 					   const struct nft_table *table,
3642 					   const struct nlattr *nla, u8 genmask)
3643 {
3644 	struct nft_trans *trans;
3645 	u32 id = ntohl(nla_get_be32(nla));
3646 
3647 	list_for_each_entry(trans, &net->nft.commit_list, list) {
3648 		if (trans->msg_type == NFT_MSG_NEWSET) {
3649 			struct nft_set *set = nft_trans_set(trans);
3650 
3651 			if (id == nft_trans_set_id(trans) &&
3652 			    set->table == table &&
3653 			    nft_active_genmask(set, genmask))
3654 				return set;
3655 		}
3656 	}
3657 	return ERR_PTR(-ENOENT);
3658 }
3659 
nft_set_lookup_global(const struct net * net,const struct nft_table * table,const struct nlattr * nla_set_name,const struct nlattr * nla_set_id,u8 genmask)3660 struct nft_set *nft_set_lookup_global(const struct net *net,
3661 				      const struct nft_table *table,
3662 				      const struct nlattr *nla_set_name,
3663 				      const struct nlattr *nla_set_id,
3664 				      u8 genmask)
3665 {
3666 	struct nft_set *set;
3667 
3668 	set = nft_set_lookup(table, nla_set_name, genmask);
3669 	if (IS_ERR(set)) {
3670 		if (!nla_set_id)
3671 			return set;
3672 
3673 		set = nft_set_lookup_byid(net, table, nla_set_id, genmask);
3674 	}
3675 	return set;
3676 }
3677 EXPORT_SYMBOL_GPL(nft_set_lookup_global);
3678 
nf_tables_set_alloc_name(struct nft_ctx * ctx,struct nft_set * set,const char * name)3679 static int nf_tables_set_alloc_name(struct nft_ctx *ctx, struct nft_set *set,
3680 				    const char *name)
3681 {
3682 	const struct nft_set *i;
3683 	const char *p;
3684 	unsigned long *inuse;
3685 	unsigned int n = 0, min = 0;
3686 
3687 	p = strchr(name, '%');
3688 	if (p != NULL) {
3689 		if (p[1] != 'd' || strchr(p + 2, '%'))
3690 			return -EINVAL;
3691 
3692 		inuse = (unsigned long *)get_zeroed_page(GFP_KERNEL);
3693 		if (inuse == NULL)
3694 			return -ENOMEM;
3695 cont:
3696 		list_for_each_entry(i, &ctx->table->sets, list) {
3697 			int tmp;
3698 
3699 			if (!nft_is_active_next(ctx->net, i))
3700 				continue;
3701 			if (!sscanf(i->name, name, &tmp))
3702 				continue;
3703 			if (tmp < min || tmp >= min + BITS_PER_BYTE * PAGE_SIZE)
3704 				continue;
3705 
3706 			set_bit(tmp - min, inuse);
3707 		}
3708 
3709 		n = find_first_zero_bit(inuse, BITS_PER_BYTE * PAGE_SIZE);
3710 		if (n >= BITS_PER_BYTE * PAGE_SIZE) {
3711 			min += BITS_PER_BYTE * PAGE_SIZE;
3712 			memset(inuse, 0, PAGE_SIZE);
3713 			goto cont;
3714 		}
3715 		free_page((unsigned long)inuse);
3716 	}
3717 
3718 	set->name = kasprintf(GFP_KERNEL, name, min + n);
3719 	if (!set->name)
3720 		return -ENOMEM;
3721 
3722 	list_for_each_entry(i, &ctx->table->sets, list) {
3723 		if (!nft_is_active_next(ctx->net, i))
3724 			continue;
3725 		if (!strcmp(set->name, i->name)) {
3726 			kfree(set->name);
3727 			set->name = NULL;
3728 			return -ENFILE;
3729 		}
3730 	}
3731 	return 0;
3732 }
3733 
nf_msecs_to_jiffies64(const struct nlattr * nla,u64 * result)3734 int nf_msecs_to_jiffies64(const struct nlattr *nla, u64 *result)
3735 {
3736 	u64 ms = be64_to_cpu(nla_get_be64(nla));
3737 	u64 max = (u64)(~((u64)0));
3738 
3739 	max = div_u64(max, NSEC_PER_MSEC);
3740 	if (ms >= max)
3741 		return -ERANGE;
3742 
3743 	ms *= NSEC_PER_MSEC;
3744 	*result = nsecs_to_jiffies64(ms);
3745 	return 0;
3746 }
3747 
nf_jiffies64_to_msecs(u64 input)3748 __be64 nf_jiffies64_to_msecs(u64 input)
3749 {
3750 	return cpu_to_be64(jiffies64_to_msecs(input));
3751 }
3752 
nf_tables_fill_set_concat(struct sk_buff * skb,const struct nft_set * set)3753 static int nf_tables_fill_set_concat(struct sk_buff *skb,
3754 				     const struct nft_set *set)
3755 {
3756 	struct nlattr *concat, *field;
3757 	int i;
3758 
3759 	concat = nla_nest_start_noflag(skb, NFTA_SET_DESC_CONCAT);
3760 	if (!concat)
3761 		return -ENOMEM;
3762 
3763 	for (i = 0; i < set->field_count; i++) {
3764 		field = nla_nest_start_noflag(skb, NFTA_LIST_ELEM);
3765 		if (!field)
3766 			return -ENOMEM;
3767 
3768 		if (nla_put_be32(skb, NFTA_SET_FIELD_LEN,
3769 				 htonl(set->field_len[i])))
3770 			return -ENOMEM;
3771 
3772 		nla_nest_end(skb, field);
3773 	}
3774 
3775 	nla_nest_end(skb, concat);
3776 
3777 	return 0;
3778 }
3779 
nf_tables_fill_set(struct sk_buff * skb,const struct nft_ctx * ctx,const struct nft_set * set,u16 event,u16 flags)3780 static int nf_tables_fill_set(struct sk_buff *skb, const struct nft_ctx *ctx,
3781 			      const struct nft_set *set, u16 event, u16 flags)
3782 {
3783 	struct nlmsghdr *nlh;
3784 	u32 portid = ctx->portid;
3785 	struct nlattr *nest;
3786 	u32 seq = ctx->seq;
3787 
3788 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
3789 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, ctx->family,
3790 			   NFNETLINK_V0, nft_base_seq(ctx->net));
3791 	if (!nlh)
3792 		goto nla_put_failure;
3793 
3794 	if (nla_put_string(skb, NFTA_SET_TABLE, ctx->table->name))
3795 		goto nla_put_failure;
3796 	if (nla_put_string(skb, NFTA_SET_NAME, set->name))
3797 		goto nla_put_failure;
3798 	if (nla_put_be64(skb, NFTA_SET_HANDLE, cpu_to_be64(set->handle),
3799 			 NFTA_SET_PAD))
3800 		goto nla_put_failure;
3801 	if (set->flags != 0)
3802 		if (nla_put_be32(skb, NFTA_SET_FLAGS, htonl(set->flags)))
3803 			goto nla_put_failure;
3804 
3805 	if (nla_put_be32(skb, NFTA_SET_KEY_TYPE, htonl(set->ktype)))
3806 		goto nla_put_failure;
3807 	if (nla_put_be32(skb, NFTA_SET_KEY_LEN, htonl(set->klen)))
3808 		goto nla_put_failure;
3809 	if (set->flags & NFT_SET_MAP) {
3810 		if (nla_put_be32(skb, NFTA_SET_DATA_TYPE, htonl(set->dtype)))
3811 			goto nla_put_failure;
3812 		if (nla_put_be32(skb, NFTA_SET_DATA_LEN, htonl(set->dlen)))
3813 			goto nla_put_failure;
3814 	}
3815 	if (set->flags & NFT_SET_OBJECT &&
3816 	    nla_put_be32(skb, NFTA_SET_OBJ_TYPE, htonl(set->objtype)))
3817 		goto nla_put_failure;
3818 
3819 	if (set->timeout &&
3820 	    nla_put_be64(skb, NFTA_SET_TIMEOUT,
3821 			 nf_jiffies64_to_msecs(set->timeout),
3822 			 NFTA_SET_PAD))
3823 		goto nla_put_failure;
3824 	if (set->gc_int &&
3825 	    nla_put_be32(skb, NFTA_SET_GC_INTERVAL, htonl(set->gc_int)))
3826 		goto nla_put_failure;
3827 
3828 	if (set->policy != NFT_SET_POL_PERFORMANCE) {
3829 		if (nla_put_be32(skb, NFTA_SET_POLICY, htonl(set->policy)))
3830 			goto nla_put_failure;
3831 	}
3832 
3833 	if (set->udata &&
3834 	    nla_put(skb, NFTA_SET_USERDATA, set->udlen, set->udata))
3835 		goto nla_put_failure;
3836 
3837 	nest = nla_nest_start_noflag(skb, NFTA_SET_DESC);
3838 	if (!nest)
3839 		goto nla_put_failure;
3840 	if (set->size &&
3841 	    nla_put_be32(skb, NFTA_SET_DESC_SIZE, htonl(set->size)))
3842 		goto nla_put_failure;
3843 
3844 	if (set->field_count > 1 &&
3845 	    nf_tables_fill_set_concat(skb, set))
3846 		goto nla_put_failure;
3847 
3848 	nla_nest_end(skb, nest);
3849 
3850 	if (set->expr) {
3851 		nest = nla_nest_start_noflag(skb, NFTA_SET_EXPR);
3852 		if (nf_tables_fill_expr_info(skb, set->expr) < 0)
3853 			goto nla_put_failure;
3854 
3855 		nla_nest_end(skb, nest);
3856 	}
3857 
3858 	nlmsg_end(skb, nlh);
3859 	return 0;
3860 
3861 nla_put_failure:
3862 	nlmsg_trim(skb, nlh);
3863 	return -1;
3864 }
3865 
nf_tables_set_notify(const struct nft_ctx * ctx,const struct nft_set * set,int event,gfp_t gfp_flags)3866 static void nf_tables_set_notify(const struct nft_ctx *ctx,
3867 				 const struct nft_set *set, int event,
3868 			         gfp_t gfp_flags)
3869 {
3870 	struct sk_buff *skb;
3871 	u32 portid = ctx->portid;
3872 	int err;
3873 
3874 	if (!ctx->report &&
3875 	    !nfnetlink_has_listeners(ctx->net, NFNLGRP_NFTABLES))
3876 		return;
3877 
3878 	skb = nlmsg_new(NLMSG_GOODSIZE, gfp_flags);
3879 	if (skb == NULL)
3880 		goto err;
3881 
3882 	err = nf_tables_fill_set(skb, ctx, set, event, 0);
3883 	if (err < 0) {
3884 		kfree_skb(skb);
3885 		goto err;
3886 	}
3887 
3888 	nft_notify_enqueue(skb, ctx->report, &ctx->net->nft.notify_list);
3889 	return;
3890 err:
3891 	nfnetlink_set_err(ctx->net, portid, NFNLGRP_NFTABLES, -ENOBUFS);
3892 }
3893 
nf_tables_dump_sets(struct sk_buff * skb,struct netlink_callback * cb)3894 static int nf_tables_dump_sets(struct sk_buff *skb, struct netlink_callback *cb)
3895 {
3896 	const struct nft_set *set;
3897 	unsigned int idx, s_idx = cb->args[0];
3898 	struct nft_table *table, *cur_table = (struct nft_table *)cb->args[2];
3899 	struct net *net = sock_net(skb->sk);
3900 	struct nft_ctx *ctx = cb->data, ctx_set;
3901 
3902 	if (cb->args[1])
3903 		return skb->len;
3904 
3905 	rcu_read_lock();
3906 	cb->seq = net->nft.base_seq;
3907 
3908 	list_for_each_entry_rcu(table, &net->nft.tables, list) {
3909 		if (ctx->family != NFPROTO_UNSPEC &&
3910 		    ctx->family != table->family)
3911 			continue;
3912 
3913 		if (ctx->table && ctx->table != table)
3914 			continue;
3915 
3916 		if (cur_table) {
3917 			if (cur_table != table)
3918 				continue;
3919 
3920 			cur_table = NULL;
3921 		}
3922 		idx = 0;
3923 		list_for_each_entry_rcu(set, &table->sets, list) {
3924 			if (idx < s_idx)
3925 				goto cont;
3926 			if (!nft_is_active(net, set))
3927 				goto cont;
3928 
3929 			ctx_set = *ctx;
3930 			ctx_set.table = table;
3931 			ctx_set.family = table->family;
3932 
3933 			if (nf_tables_fill_set(skb, &ctx_set, set,
3934 					       NFT_MSG_NEWSET,
3935 					       NLM_F_MULTI) < 0) {
3936 				cb->args[0] = idx;
3937 				cb->args[2] = (unsigned long) table;
3938 				goto done;
3939 			}
3940 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
3941 cont:
3942 			idx++;
3943 		}
3944 		if (s_idx)
3945 			s_idx = 0;
3946 	}
3947 	cb->args[1] = 1;
3948 done:
3949 	rcu_read_unlock();
3950 	return skb->len;
3951 }
3952 
nf_tables_dump_sets_start(struct netlink_callback * cb)3953 static int nf_tables_dump_sets_start(struct netlink_callback *cb)
3954 {
3955 	struct nft_ctx *ctx_dump = NULL;
3956 
3957 	ctx_dump = kmemdup(cb->data, sizeof(*ctx_dump), GFP_ATOMIC);
3958 	if (ctx_dump == NULL)
3959 		return -ENOMEM;
3960 
3961 	cb->data = ctx_dump;
3962 	return 0;
3963 }
3964 
nf_tables_dump_sets_done(struct netlink_callback * cb)3965 static int nf_tables_dump_sets_done(struct netlink_callback *cb)
3966 {
3967 	kfree(cb->data);
3968 	return 0;
3969 }
3970 
3971 /* called with rcu_read_lock held */
nf_tables_getset(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)3972 static int nf_tables_getset(struct net *net, struct sock *nlsk,
3973 			    struct sk_buff *skb, const struct nlmsghdr *nlh,
3974 			    const struct nlattr * const nla[],
3975 			    struct netlink_ext_ack *extack)
3976 {
3977 	u8 genmask = nft_genmask_cur(net);
3978 	const struct nft_set *set;
3979 	struct nft_ctx ctx;
3980 	struct sk_buff *skb2;
3981 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3982 	int err;
3983 
3984 	/* Verify existence before starting dump */
3985 	err = nft_ctx_init_from_setattr(&ctx, net, skb, nlh, nla, extack,
3986 					genmask);
3987 	if (err < 0)
3988 		return err;
3989 
3990 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
3991 		struct netlink_dump_control c = {
3992 			.start = nf_tables_dump_sets_start,
3993 			.dump = nf_tables_dump_sets,
3994 			.done = nf_tables_dump_sets_done,
3995 			.data = &ctx,
3996 			.module = THIS_MODULE,
3997 		};
3998 
3999 		return nft_netlink_dump_start_rcu(nlsk, skb, nlh, &c);
4000 	}
4001 
4002 	/* Only accept unspec with dump */
4003 	if (nfmsg->nfgen_family == NFPROTO_UNSPEC)
4004 		return -EAFNOSUPPORT;
4005 	if (!nla[NFTA_SET_TABLE])
4006 		return -EINVAL;
4007 
4008 	set = nft_set_lookup(ctx.table, nla[NFTA_SET_NAME], genmask);
4009 	if (IS_ERR(set))
4010 		return PTR_ERR(set);
4011 
4012 	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
4013 	if (skb2 == NULL)
4014 		return -ENOMEM;
4015 
4016 	err = nf_tables_fill_set(skb2, &ctx, set, NFT_MSG_NEWSET, 0);
4017 	if (err < 0)
4018 		goto err_fill_set_info;
4019 
4020 	return nfnetlink_unicast(skb2, net, NETLINK_CB(skb).portid);
4021 
4022 err_fill_set_info:
4023 	kfree_skb(skb2);
4024 	return err;
4025 }
4026 
4027 static const struct nla_policy nft_concat_policy[NFTA_SET_FIELD_MAX + 1] = {
4028 	[NFTA_SET_FIELD_LEN]	= { .type = NLA_U32 },
4029 };
4030 
nft_set_desc_concat_parse(const struct nlattr * attr,struct nft_set_desc * desc)4031 static int nft_set_desc_concat_parse(const struct nlattr *attr,
4032 				     struct nft_set_desc *desc)
4033 {
4034 	struct nlattr *tb[NFTA_SET_FIELD_MAX + 1];
4035 	u32 len;
4036 	int err;
4037 
4038 	if (desc->field_count >= ARRAY_SIZE(desc->field_len))
4039 		return -E2BIG;
4040 
4041 	err = nla_parse_nested_deprecated(tb, NFTA_SET_FIELD_MAX, attr,
4042 					  nft_concat_policy, NULL);
4043 	if (err < 0)
4044 		return err;
4045 
4046 	if (!tb[NFTA_SET_FIELD_LEN])
4047 		return -EINVAL;
4048 
4049 	len = ntohl(nla_get_be32(tb[NFTA_SET_FIELD_LEN]));
4050 	if (!len || len > U8_MAX)
4051 		return -EINVAL;
4052 
4053 	desc->field_len[desc->field_count++] = len;
4054 
4055 	return 0;
4056 }
4057 
nft_set_desc_concat(struct nft_set_desc * desc,const struct nlattr * nla)4058 static int nft_set_desc_concat(struct nft_set_desc *desc,
4059 			       const struct nlattr *nla)
4060 {
4061 	struct nlattr *attr;
4062 	u32 num_regs = 0;
4063 	int rem, err, i;
4064 
4065 	nla_for_each_nested(attr, nla, rem) {
4066 		if (nla_type(attr) != NFTA_LIST_ELEM)
4067 			return -EINVAL;
4068 
4069 		err = nft_set_desc_concat_parse(attr, desc);
4070 		if (err < 0)
4071 			return err;
4072 	}
4073 
4074 	for (i = 0; i < desc->field_count; i++)
4075 		num_regs += DIV_ROUND_UP(desc->field_len[i], sizeof(u32));
4076 
4077 	if (num_regs > NFT_REG32_COUNT)
4078 		return -E2BIG;
4079 
4080 	return 0;
4081 }
4082 
nf_tables_set_desc_parse(struct nft_set_desc * desc,const struct nlattr * nla)4083 static int nf_tables_set_desc_parse(struct nft_set_desc *desc,
4084 				    const struct nlattr *nla)
4085 {
4086 	struct nlattr *da[NFTA_SET_DESC_MAX + 1];
4087 	int err;
4088 
4089 	err = nla_parse_nested_deprecated(da, NFTA_SET_DESC_MAX, nla,
4090 					  nft_set_desc_policy, NULL);
4091 	if (err < 0)
4092 		return err;
4093 
4094 	if (da[NFTA_SET_DESC_SIZE] != NULL)
4095 		desc->size = ntohl(nla_get_be32(da[NFTA_SET_DESC_SIZE]));
4096 	if (da[NFTA_SET_DESC_CONCAT])
4097 		err = nft_set_desc_concat(desc, da[NFTA_SET_DESC_CONCAT]);
4098 
4099 	return err;
4100 }
4101 
nf_tables_newset(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)4102 static int nf_tables_newset(struct net *net, struct sock *nlsk,
4103 			    struct sk_buff *skb, const struct nlmsghdr *nlh,
4104 			    const struct nlattr * const nla[],
4105 			    struct netlink_ext_ack *extack)
4106 {
4107 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
4108 	u8 genmask = nft_genmask_next(net);
4109 	int family = nfmsg->nfgen_family;
4110 	const struct nft_set_ops *ops;
4111 	struct nft_expr *expr = NULL;
4112 	struct nft_table *table;
4113 	struct nft_set *set;
4114 	struct nft_ctx ctx;
4115 	size_t alloc_size;
4116 	char *name;
4117 	u64 size;
4118 	u64 timeout;
4119 	u32 ktype, dtype, flags, policy, gc_int, objtype;
4120 	struct nft_set_desc desc;
4121 	unsigned char *udata;
4122 	u16 udlen;
4123 	int err;
4124 	int i;
4125 
4126 	if (nla[NFTA_SET_TABLE] == NULL ||
4127 	    nla[NFTA_SET_NAME] == NULL ||
4128 	    nla[NFTA_SET_KEY_LEN] == NULL ||
4129 	    nla[NFTA_SET_ID] == NULL)
4130 		return -EINVAL;
4131 
4132 	memset(&desc, 0, sizeof(desc));
4133 
4134 	ktype = NFT_DATA_VALUE;
4135 	if (nla[NFTA_SET_KEY_TYPE] != NULL) {
4136 		ktype = ntohl(nla_get_be32(nla[NFTA_SET_KEY_TYPE]));
4137 		if ((ktype & NFT_DATA_RESERVED_MASK) == NFT_DATA_RESERVED_MASK)
4138 			return -EINVAL;
4139 	}
4140 
4141 	desc.klen = ntohl(nla_get_be32(nla[NFTA_SET_KEY_LEN]));
4142 	if (desc.klen == 0 || desc.klen > NFT_DATA_VALUE_MAXLEN)
4143 		return -EINVAL;
4144 
4145 	flags = 0;
4146 	if (nla[NFTA_SET_FLAGS] != NULL) {
4147 		flags = ntohl(nla_get_be32(nla[NFTA_SET_FLAGS]));
4148 		if (flags & ~(NFT_SET_ANONYMOUS | NFT_SET_CONSTANT |
4149 			      NFT_SET_INTERVAL | NFT_SET_TIMEOUT |
4150 			      NFT_SET_MAP | NFT_SET_EVAL |
4151 			      NFT_SET_OBJECT | NFT_SET_CONCAT))
4152 			return -EOPNOTSUPP;
4153 		/* Only one of these operations is supported */
4154 		if ((flags & (NFT_SET_MAP | NFT_SET_OBJECT)) ==
4155 			     (NFT_SET_MAP | NFT_SET_OBJECT))
4156 			return -EOPNOTSUPP;
4157 		if ((flags & (NFT_SET_EVAL | NFT_SET_OBJECT)) ==
4158 			     (NFT_SET_EVAL | NFT_SET_OBJECT))
4159 			return -EOPNOTSUPP;
4160 	}
4161 
4162 	dtype = 0;
4163 	if (nla[NFTA_SET_DATA_TYPE] != NULL) {
4164 		if (!(flags & NFT_SET_MAP))
4165 			return -EINVAL;
4166 
4167 		dtype = ntohl(nla_get_be32(nla[NFTA_SET_DATA_TYPE]));
4168 		if ((dtype & NFT_DATA_RESERVED_MASK) == NFT_DATA_RESERVED_MASK &&
4169 		    dtype != NFT_DATA_VERDICT)
4170 			return -EINVAL;
4171 
4172 		if (dtype != NFT_DATA_VERDICT) {
4173 			if (nla[NFTA_SET_DATA_LEN] == NULL)
4174 				return -EINVAL;
4175 			desc.dlen = ntohl(nla_get_be32(nla[NFTA_SET_DATA_LEN]));
4176 			if (desc.dlen == 0 || desc.dlen > NFT_DATA_VALUE_MAXLEN)
4177 				return -EINVAL;
4178 		} else
4179 			desc.dlen = sizeof(struct nft_verdict);
4180 	} else if (flags & NFT_SET_MAP)
4181 		return -EINVAL;
4182 
4183 	if (nla[NFTA_SET_OBJ_TYPE] != NULL) {
4184 		if (!(flags & NFT_SET_OBJECT))
4185 			return -EINVAL;
4186 
4187 		objtype = ntohl(nla_get_be32(nla[NFTA_SET_OBJ_TYPE]));
4188 		if (objtype == NFT_OBJECT_UNSPEC ||
4189 		    objtype > NFT_OBJECT_MAX)
4190 			return -EOPNOTSUPP;
4191 	} else if (flags & NFT_SET_OBJECT)
4192 		return -EINVAL;
4193 	else
4194 		objtype = NFT_OBJECT_UNSPEC;
4195 
4196 	timeout = 0;
4197 	if (nla[NFTA_SET_TIMEOUT] != NULL) {
4198 		if (!(flags & NFT_SET_TIMEOUT))
4199 			return -EINVAL;
4200 
4201 		err = nf_msecs_to_jiffies64(nla[NFTA_SET_TIMEOUT], &timeout);
4202 		if (err)
4203 			return err;
4204 	}
4205 	gc_int = 0;
4206 	if (nla[NFTA_SET_GC_INTERVAL] != NULL) {
4207 		if (!(flags & NFT_SET_TIMEOUT))
4208 			return -EINVAL;
4209 		gc_int = ntohl(nla_get_be32(nla[NFTA_SET_GC_INTERVAL]));
4210 	}
4211 
4212 	policy = NFT_SET_POL_PERFORMANCE;
4213 	if (nla[NFTA_SET_POLICY] != NULL)
4214 		policy = ntohl(nla_get_be32(nla[NFTA_SET_POLICY]));
4215 
4216 	if (nla[NFTA_SET_DESC] != NULL) {
4217 		err = nf_tables_set_desc_parse(&desc, nla[NFTA_SET_DESC]);
4218 		if (err < 0)
4219 			return err;
4220 
4221 		if (desc.field_count > 1 && !(flags & NFT_SET_CONCAT))
4222 			return -EINVAL;
4223 	} else if (flags & NFT_SET_CONCAT) {
4224 		return -EINVAL;
4225 	}
4226 
4227 	if (nla[NFTA_SET_EXPR])
4228 		desc.expr = true;
4229 
4230 	table = nft_table_lookup(net, nla[NFTA_SET_TABLE], family, genmask);
4231 	if (IS_ERR(table)) {
4232 		NL_SET_BAD_ATTR(extack, nla[NFTA_SET_TABLE]);
4233 		return PTR_ERR(table);
4234 	}
4235 
4236 	nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
4237 
4238 	set = nft_set_lookup(table, nla[NFTA_SET_NAME], genmask);
4239 	if (IS_ERR(set)) {
4240 		if (PTR_ERR(set) != -ENOENT) {
4241 			NL_SET_BAD_ATTR(extack, nla[NFTA_SET_NAME]);
4242 			return PTR_ERR(set);
4243 		}
4244 	} else {
4245 		if (nlh->nlmsg_flags & NLM_F_EXCL) {
4246 			NL_SET_BAD_ATTR(extack, nla[NFTA_SET_NAME]);
4247 			return -EEXIST;
4248 		}
4249 		if (nlh->nlmsg_flags & NLM_F_REPLACE)
4250 			return -EOPNOTSUPP;
4251 
4252 		return 0;
4253 	}
4254 
4255 	if (!(nlh->nlmsg_flags & NLM_F_CREATE))
4256 		return -ENOENT;
4257 
4258 	ops = nft_select_set_ops(&ctx, nla, &desc, policy);
4259 	if (IS_ERR(ops))
4260 		return PTR_ERR(ops);
4261 
4262 	udlen = 0;
4263 	if (nla[NFTA_SET_USERDATA])
4264 		udlen = nla_len(nla[NFTA_SET_USERDATA]);
4265 
4266 	size = 0;
4267 	if (ops->privsize != NULL)
4268 		size = ops->privsize(nla, &desc);
4269 	alloc_size = sizeof(*set) + size + udlen;
4270 	if (alloc_size < size || alloc_size > INT_MAX)
4271 		return -ENOMEM;
4272 	set = kvzalloc(alloc_size, GFP_KERNEL);
4273 	if (!set)
4274 		return -ENOMEM;
4275 
4276 	name = nla_strdup(nla[NFTA_SET_NAME], GFP_KERNEL);
4277 	if (!name) {
4278 		err = -ENOMEM;
4279 		goto err_set_name;
4280 	}
4281 
4282 	err = nf_tables_set_alloc_name(&ctx, set, name);
4283 	kfree(name);
4284 	if (err < 0)
4285 		goto err_set_name;
4286 
4287 	udata = NULL;
4288 	if (udlen) {
4289 		udata = set->data + size;
4290 		nla_memcpy(udata, nla[NFTA_SET_USERDATA], udlen);
4291 	}
4292 
4293 	INIT_LIST_HEAD(&set->bindings);
4294 	set->table = table;
4295 	write_pnet(&set->net, net);
4296 	set->ops = ops;
4297 	set->ktype = ktype;
4298 	set->klen = desc.klen;
4299 	set->dtype = dtype;
4300 	set->objtype = objtype;
4301 	set->dlen = desc.dlen;
4302 	set->flags = flags;
4303 	set->size = desc.size;
4304 	set->policy = policy;
4305 	set->udlen = udlen;
4306 	set->udata = udata;
4307 	set->timeout = timeout;
4308 	set->gc_int = gc_int;
4309 
4310 	set->field_count = desc.field_count;
4311 	for (i = 0; i < desc.field_count; i++)
4312 		set->field_len[i] = desc.field_len[i];
4313 
4314 	err = ops->init(set, &desc, nla);
4315 	if (err < 0)
4316 		goto err_set_init;
4317 
4318 	if (nla[NFTA_SET_EXPR]) {
4319 		expr = nft_set_elem_expr_alloc(&ctx, set, nla[NFTA_SET_EXPR]);
4320 		if (IS_ERR(expr)) {
4321 			err = PTR_ERR(expr);
4322 			goto err_set_expr_alloc;
4323 		}
4324 
4325 		set->expr = expr;
4326 	}
4327 
4328 	set->handle = nf_tables_alloc_handle(table);
4329 
4330 	err = nft_trans_set_add(&ctx, NFT_MSG_NEWSET, set);
4331 	if (err < 0)
4332 		goto err_set_expr_alloc;
4333 
4334 	list_add_tail_rcu(&set->list, &table->sets);
4335 	table->use++;
4336 	return 0;
4337 
4338 err_set_expr_alloc:
4339 	if (set->expr)
4340 		nft_expr_destroy(&ctx, set->expr);
4341 
4342 	ops->destroy(set);
4343 err_set_init:
4344 	kfree(set->name);
4345 err_set_name:
4346 	kvfree(set);
4347 	return err;
4348 }
4349 
nft_set_destroy(const struct nft_ctx * ctx,struct nft_set * set)4350 static void nft_set_destroy(const struct nft_ctx *ctx, struct nft_set *set)
4351 {
4352 	if (WARN_ON(set->use > 0))
4353 		return;
4354 
4355 	if (set->expr)
4356 		nft_expr_destroy(ctx, set->expr);
4357 
4358 	set->ops->destroy(set);
4359 	kfree(set->name);
4360 	kvfree(set);
4361 }
4362 
nf_tables_delset(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)4363 static int nf_tables_delset(struct net *net, struct sock *nlsk,
4364 			    struct sk_buff *skb, const struct nlmsghdr *nlh,
4365 			    const struct nlattr * const nla[],
4366 			    struct netlink_ext_ack *extack)
4367 {
4368 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
4369 	u8 genmask = nft_genmask_next(net);
4370 	const struct nlattr *attr;
4371 	struct nft_set *set;
4372 	struct nft_ctx ctx;
4373 	int err;
4374 
4375 	if (nfmsg->nfgen_family == NFPROTO_UNSPEC)
4376 		return -EAFNOSUPPORT;
4377 	if (nla[NFTA_SET_TABLE] == NULL)
4378 		return -EINVAL;
4379 
4380 	err = nft_ctx_init_from_setattr(&ctx, net, skb, nlh, nla, extack,
4381 					genmask);
4382 	if (err < 0)
4383 		return err;
4384 
4385 	if (nla[NFTA_SET_HANDLE]) {
4386 		attr = nla[NFTA_SET_HANDLE];
4387 		set = nft_set_lookup_byhandle(ctx.table, attr, genmask);
4388 	} else {
4389 		attr = nla[NFTA_SET_NAME];
4390 		set = nft_set_lookup(ctx.table, attr, genmask);
4391 	}
4392 
4393 	if (IS_ERR(set)) {
4394 		NL_SET_BAD_ATTR(extack, attr);
4395 		return PTR_ERR(set);
4396 	}
4397 	if (set->use ||
4398 	    (nlh->nlmsg_flags & NLM_F_NONREC && atomic_read(&set->nelems) > 0)) {
4399 		NL_SET_BAD_ATTR(extack, attr);
4400 		return -EBUSY;
4401 	}
4402 
4403 	return nft_delset(&ctx, set);
4404 }
4405 
4406 static int nft_validate_register_store(const struct nft_ctx *ctx,
4407 				       enum nft_registers reg,
4408 				       const struct nft_data *data,
4409 				       enum nft_data_types type,
4410 				       unsigned int len);
4411 
nf_tables_bind_check_setelem(const struct nft_ctx * ctx,struct nft_set * set,const struct nft_set_iter * iter,struct nft_set_elem * elem)4412 static int nf_tables_bind_check_setelem(const struct nft_ctx *ctx,
4413 					struct nft_set *set,
4414 					const struct nft_set_iter *iter,
4415 					struct nft_set_elem *elem)
4416 {
4417 	const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
4418 	enum nft_registers dreg;
4419 
4420 	dreg = nft_type_to_reg(set->dtype);
4421 	return nft_validate_register_store(ctx, dreg, nft_set_ext_data(ext),
4422 					   set->dtype == NFT_DATA_VERDICT ?
4423 					   NFT_DATA_VERDICT : NFT_DATA_VALUE,
4424 					   set->dlen);
4425 }
4426 
nf_tables_bind_set(const struct nft_ctx * ctx,struct nft_set * set,struct nft_set_binding * binding)4427 int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
4428 		       struct nft_set_binding *binding)
4429 {
4430 	struct nft_set_binding *i;
4431 	struct nft_set_iter iter;
4432 
4433 	if (set->use == UINT_MAX)
4434 		return -EOVERFLOW;
4435 
4436 	if (!list_empty(&set->bindings) && nft_set_is_anonymous(set))
4437 		return -EBUSY;
4438 
4439 	if (binding->flags & NFT_SET_MAP) {
4440 		/* If the set is already bound to the same chain all
4441 		 * jumps are already validated for that chain.
4442 		 */
4443 		list_for_each_entry(i, &set->bindings, list) {
4444 			if (i->flags & NFT_SET_MAP &&
4445 			    i->chain == binding->chain)
4446 				goto bind;
4447 		}
4448 
4449 		iter.genmask	= nft_genmask_next(ctx->net);
4450 		iter.skip 	= 0;
4451 		iter.count	= 0;
4452 		iter.err	= 0;
4453 		iter.fn		= nf_tables_bind_check_setelem;
4454 
4455 		set->ops->walk(ctx, set, &iter);
4456 		if (iter.err < 0)
4457 			return iter.err;
4458 	}
4459 bind:
4460 	binding->chain = ctx->chain;
4461 	list_add_tail_rcu(&binding->list, &set->bindings);
4462 	nft_set_trans_bind(ctx, set);
4463 	set->use++;
4464 
4465 	return 0;
4466 }
4467 EXPORT_SYMBOL_GPL(nf_tables_bind_set);
4468 
nf_tables_unbind_set(const struct nft_ctx * ctx,struct nft_set * set,struct nft_set_binding * binding,bool event)4469 static void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set,
4470 				 struct nft_set_binding *binding, bool event)
4471 {
4472 	list_del_rcu(&binding->list);
4473 
4474 	if (list_empty(&set->bindings) && nft_set_is_anonymous(set)) {
4475 		list_del_rcu(&set->list);
4476 		if (event)
4477 			nf_tables_set_notify(ctx, set, NFT_MSG_DELSET,
4478 					     GFP_KERNEL);
4479 	}
4480 }
4481 
nf_tables_deactivate_set(const struct nft_ctx * ctx,struct nft_set * set,struct nft_set_binding * binding,enum nft_trans_phase phase)4482 void nf_tables_deactivate_set(const struct nft_ctx *ctx, struct nft_set *set,
4483 			      struct nft_set_binding *binding,
4484 			      enum nft_trans_phase phase)
4485 {
4486 	switch (phase) {
4487 	case NFT_TRANS_PREPARE:
4488 		set->use--;
4489 		return;
4490 	case NFT_TRANS_ABORT:
4491 	case NFT_TRANS_RELEASE:
4492 		set->use--;
4493 		fallthrough;
4494 	default:
4495 		nf_tables_unbind_set(ctx, set, binding,
4496 				     phase == NFT_TRANS_COMMIT);
4497 	}
4498 }
4499 EXPORT_SYMBOL_GPL(nf_tables_deactivate_set);
4500 
nf_tables_destroy_set(const struct nft_ctx * ctx,struct nft_set * set)4501 void nf_tables_destroy_set(const struct nft_ctx *ctx, struct nft_set *set)
4502 {
4503 	if (list_empty(&set->bindings) && nft_set_is_anonymous(set))
4504 		nft_set_destroy(ctx, set);
4505 }
4506 EXPORT_SYMBOL_GPL(nf_tables_destroy_set);
4507 
4508 const struct nft_set_ext_type nft_set_ext_types[] = {
4509 	[NFT_SET_EXT_KEY]		= {
4510 		.align	= __alignof__(u32),
4511 	},
4512 	[NFT_SET_EXT_DATA]		= {
4513 		.align	= __alignof__(u32),
4514 	},
4515 	[NFT_SET_EXT_EXPR]		= {
4516 		.align	= __alignof__(struct nft_expr),
4517 	},
4518 	[NFT_SET_EXT_OBJREF]		= {
4519 		.len	= sizeof(struct nft_object *),
4520 		.align	= __alignof__(struct nft_object *),
4521 	},
4522 	[NFT_SET_EXT_FLAGS]		= {
4523 		.len	= sizeof(u8),
4524 		.align	= __alignof__(u8),
4525 	},
4526 	[NFT_SET_EXT_TIMEOUT]		= {
4527 		.len	= sizeof(u64),
4528 		.align	= __alignof__(u64),
4529 	},
4530 	[NFT_SET_EXT_EXPIRATION]	= {
4531 		.len	= sizeof(u64),
4532 		.align	= __alignof__(u64),
4533 	},
4534 	[NFT_SET_EXT_USERDATA]		= {
4535 		.len	= sizeof(struct nft_userdata),
4536 		.align	= __alignof__(struct nft_userdata),
4537 	},
4538 	[NFT_SET_EXT_KEY_END]		= {
4539 		.align	= __alignof__(u32),
4540 	},
4541 };
4542 
4543 /*
4544  * Set elements
4545  */
4546 
4547 static const struct nla_policy nft_set_elem_policy[NFTA_SET_ELEM_MAX + 1] = {
4548 	[NFTA_SET_ELEM_KEY]		= { .type = NLA_NESTED },
4549 	[NFTA_SET_ELEM_DATA]		= { .type = NLA_NESTED },
4550 	[NFTA_SET_ELEM_FLAGS]		= { .type = NLA_U32 },
4551 	[NFTA_SET_ELEM_TIMEOUT]		= { .type = NLA_U64 },
4552 	[NFTA_SET_ELEM_EXPIRATION]	= { .type = NLA_U64 },
4553 	[NFTA_SET_ELEM_USERDATA]	= { .type = NLA_BINARY,
4554 					    .len = NFT_USERDATA_MAXLEN },
4555 	[NFTA_SET_ELEM_EXPR]		= { .type = NLA_NESTED },
4556 	[NFTA_SET_ELEM_OBJREF]		= { .type = NLA_STRING,
4557 					    .len = NFT_OBJ_MAXNAMELEN - 1 },
4558 	[NFTA_SET_ELEM_KEY_END]		= { .type = NLA_NESTED },
4559 };
4560 
4561 static const struct nla_policy nft_set_elem_list_policy[NFTA_SET_ELEM_LIST_MAX + 1] = {
4562 	[NFTA_SET_ELEM_LIST_TABLE]	= { .type = NLA_STRING,
4563 					    .len = NFT_TABLE_MAXNAMELEN - 1 },
4564 	[NFTA_SET_ELEM_LIST_SET]	= { .type = NLA_STRING,
4565 					    .len = NFT_SET_MAXNAMELEN - 1 },
4566 	[NFTA_SET_ELEM_LIST_ELEMENTS]	= { .type = NLA_NESTED },
4567 	[NFTA_SET_ELEM_LIST_SET_ID]	= { .type = NLA_U32 },
4568 };
4569 
nft_ctx_init_from_elemattr(struct nft_ctx * ctx,struct net * net,const struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack,u8 genmask)4570 static int nft_ctx_init_from_elemattr(struct nft_ctx *ctx, struct net *net,
4571 				      const struct sk_buff *skb,
4572 				      const struct nlmsghdr *nlh,
4573 				      const struct nlattr * const nla[],
4574 				      struct netlink_ext_ack *extack,
4575 				      u8 genmask)
4576 {
4577 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
4578 	int family = nfmsg->nfgen_family;
4579 	struct nft_table *table;
4580 
4581 	table = nft_table_lookup(net, nla[NFTA_SET_ELEM_LIST_TABLE], family,
4582 				 genmask);
4583 	if (IS_ERR(table)) {
4584 		NL_SET_BAD_ATTR(extack, nla[NFTA_SET_ELEM_LIST_TABLE]);
4585 		return PTR_ERR(table);
4586 	}
4587 
4588 	nft_ctx_init(ctx, net, skb, nlh, family, table, NULL, nla);
4589 	return 0;
4590 }
4591 
nf_tables_fill_setelem(struct sk_buff * skb,const struct nft_set * set,const struct nft_set_elem * elem)4592 static int nf_tables_fill_setelem(struct sk_buff *skb,
4593 				  const struct nft_set *set,
4594 				  const struct nft_set_elem *elem)
4595 {
4596 	const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
4597 	unsigned char *b = skb_tail_pointer(skb);
4598 	struct nlattr *nest;
4599 
4600 	nest = nla_nest_start_noflag(skb, NFTA_LIST_ELEM);
4601 	if (nest == NULL)
4602 		goto nla_put_failure;
4603 
4604 	if (nft_data_dump(skb, NFTA_SET_ELEM_KEY, nft_set_ext_key(ext),
4605 			  NFT_DATA_VALUE, set->klen) < 0)
4606 		goto nla_put_failure;
4607 
4608 	if (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END) &&
4609 	    nft_data_dump(skb, NFTA_SET_ELEM_KEY_END, nft_set_ext_key_end(ext),
4610 			  NFT_DATA_VALUE, set->klen) < 0)
4611 		goto nla_put_failure;
4612 
4613 	if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA) &&
4614 	    nft_data_dump(skb, NFTA_SET_ELEM_DATA, nft_set_ext_data(ext),
4615 			  set->dtype == NFT_DATA_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE,
4616 			  set->dlen) < 0)
4617 		goto nla_put_failure;
4618 
4619 	if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPR) &&
4620 	    nft_expr_dump(skb, NFTA_SET_ELEM_EXPR, nft_set_ext_expr(ext)) < 0)
4621 		goto nla_put_failure;
4622 
4623 	if (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF) &&
4624 	    nla_put_string(skb, NFTA_SET_ELEM_OBJREF,
4625 			   (*nft_set_ext_obj(ext))->key.name) < 0)
4626 		goto nla_put_failure;
4627 
4628 	if (nft_set_ext_exists(ext, NFT_SET_EXT_FLAGS) &&
4629 	    nla_put_be32(skb, NFTA_SET_ELEM_FLAGS,
4630 		         htonl(*nft_set_ext_flags(ext))))
4631 		goto nla_put_failure;
4632 
4633 	if (nft_set_ext_exists(ext, NFT_SET_EXT_TIMEOUT) &&
4634 	    nla_put_be64(skb, NFTA_SET_ELEM_TIMEOUT,
4635 			 nf_jiffies64_to_msecs(*nft_set_ext_timeout(ext)),
4636 			 NFTA_SET_ELEM_PAD))
4637 		goto nla_put_failure;
4638 
4639 	if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION)) {
4640 		u64 expires, now = get_jiffies_64();
4641 
4642 		expires = *nft_set_ext_expiration(ext);
4643 		if (time_before64(now, expires))
4644 			expires -= now;
4645 		else
4646 			expires = 0;
4647 
4648 		if (nla_put_be64(skb, NFTA_SET_ELEM_EXPIRATION,
4649 				 nf_jiffies64_to_msecs(expires),
4650 				 NFTA_SET_ELEM_PAD))
4651 			goto nla_put_failure;
4652 	}
4653 
4654 	if (nft_set_ext_exists(ext, NFT_SET_EXT_USERDATA)) {
4655 		struct nft_userdata *udata;
4656 
4657 		udata = nft_set_ext_userdata(ext);
4658 		if (nla_put(skb, NFTA_SET_ELEM_USERDATA,
4659 			    udata->len + 1, udata->data))
4660 			goto nla_put_failure;
4661 	}
4662 
4663 	nla_nest_end(skb, nest);
4664 	return 0;
4665 
4666 nla_put_failure:
4667 	nlmsg_trim(skb, b);
4668 	return -EMSGSIZE;
4669 }
4670 
4671 struct nft_set_dump_args {
4672 	const struct netlink_callback	*cb;
4673 	struct nft_set_iter		iter;
4674 	struct sk_buff			*skb;
4675 };
4676 
nf_tables_dump_setelem(const struct nft_ctx * ctx,struct nft_set * set,const struct nft_set_iter * iter,struct nft_set_elem * elem)4677 static int nf_tables_dump_setelem(const struct nft_ctx *ctx,
4678 				  struct nft_set *set,
4679 				  const struct nft_set_iter *iter,
4680 				  struct nft_set_elem *elem)
4681 {
4682 	struct nft_set_dump_args *args;
4683 
4684 	args = container_of(iter, struct nft_set_dump_args, iter);
4685 	return nf_tables_fill_setelem(args->skb, set, elem);
4686 }
4687 
4688 struct nft_set_dump_ctx {
4689 	const struct nft_set	*set;
4690 	struct nft_ctx		ctx;
4691 };
4692 
nf_tables_dump_set(struct sk_buff * skb,struct netlink_callback * cb)4693 static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb)
4694 {
4695 	struct nft_set_dump_ctx *dump_ctx = cb->data;
4696 	struct net *net = sock_net(skb->sk);
4697 	struct nft_table *table;
4698 	struct nft_set *set;
4699 	struct nft_set_dump_args args;
4700 	bool set_found = false;
4701 	struct nlmsghdr *nlh;
4702 	struct nlattr *nest;
4703 	u32 portid, seq;
4704 	int event;
4705 
4706 	rcu_read_lock();
4707 	list_for_each_entry_rcu(table, &net->nft.tables, list) {
4708 		if (dump_ctx->ctx.family != NFPROTO_UNSPEC &&
4709 		    dump_ctx->ctx.family != table->family)
4710 			continue;
4711 
4712 		if (table != dump_ctx->ctx.table)
4713 			continue;
4714 
4715 		list_for_each_entry_rcu(set, &table->sets, list) {
4716 			if (set == dump_ctx->set) {
4717 				set_found = true;
4718 				break;
4719 			}
4720 		}
4721 		break;
4722 	}
4723 
4724 	if (!set_found) {
4725 		rcu_read_unlock();
4726 		return -ENOENT;
4727 	}
4728 
4729 	event  = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWSETELEM);
4730 	portid = NETLINK_CB(cb->skb).portid;
4731 	seq    = cb->nlh->nlmsg_seq;
4732 
4733 	nlh = nfnl_msg_put(skb, portid, seq, event, NLM_F_MULTI,
4734 			   table->family, NFNETLINK_V0, nft_base_seq(net));
4735 	if (!nlh)
4736 		goto nla_put_failure;
4737 
4738 	if (nla_put_string(skb, NFTA_SET_ELEM_LIST_TABLE, table->name))
4739 		goto nla_put_failure;
4740 	if (nla_put_string(skb, NFTA_SET_ELEM_LIST_SET, set->name))
4741 		goto nla_put_failure;
4742 
4743 	nest = nla_nest_start_noflag(skb, NFTA_SET_ELEM_LIST_ELEMENTS);
4744 	if (nest == NULL)
4745 		goto nla_put_failure;
4746 
4747 	args.cb			= cb;
4748 	args.skb		= skb;
4749 	args.iter.genmask	= nft_genmask_cur(net);
4750 	args.iter.skip		= cb->args[0];
4751 	args.iter.count		= 0;
4752 	args.iter.err		= 0;
4753 	args.iter.fn		= nf_tables_dump_setelem;
4754 	set->ops->walk(&dump_ctx->ctx, set, &args.iter);
4755 	rcu_read_unlock();
4756 
4757 	nla_nest_end(skb, nest);
4758 	nlmsg_end(skb, nlh);
4759 
4760 	if (args.iter.err && args.iter.err != -EMSGSIZE)
4761 		return args.iter.err;
4762 	if (args.iter.count == cb->args[0])
4763 		return 0;
4764 
4765 	cb->args[0] = args.iter.count;
4766 	return skb->len;
4767 
4768 nla_put_failure:
4769 	rcu_read_unlock();
4770 	return -ENOSPC;
4771 }
4772 
nf_tables_dump_set_start(struct netlink_callback * cb)4773 static int nf_tables_dump_set_start(struct netlink_callback *cb)
4774 {
4775 	struct nft_set_dump_ctx *dump_ctx = cb->data;
4776 
4777 	cb->data = kmemdup(dump_ctx, sizeof(*dump_ctx), GFP_ATOMIC);
4778 
4779 	return cb->data ? 0 : -ENOMEM;
4780 }
4781 
nf_tables_dump_set_done(struct netlink_callback * cb)4782 static int nf_tables_dump_set_done(struct netlink_callback *cb)
4783 {
4784 	kfree(cb->data);
4785 	return 0;
4786 }
4787 
nf_tables_fill_setelem_info(struct sk_buff * skb,const struct nft_ctx * ctx,u32 seq,u32 portid,int event,u16 flags,const struct nft_set * set,const struct nft_set_elem * elem)4788 static int nf_tables_fill_setelem_info(struct sk_buff *skb,
4789 				       const struct nft_ctx *ctx, u32 seq,
4790 				       u32 portid, int event, u16 flags,
4791 				       const struct nft_set *set,
4792 				       const struct nft_set_elem *elem)
4793 {
4794 	struct nlmsghdr *nlh;
4795 	struct nlattr *nest;
4796 	int err;
4797 
4798 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
4799 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, ctx->family,
4800 			   NFNETLINK_V0, nft_base_seq(ctx->net));
4801 	if (!nlh)
4802 		goto nla_put_failure;
4803 
4804 	if (nla_put_string(skb, NFTA_SET_TABLE, ctx->table->name))
4805 		goto nla_put_failure;
4806 	if (nla_put_string(skb, NFTA_SET_NAME, set->name))
4807 		goto nla_put_failure;
4808 
4809 	nest = nla_nest_start_noflag(skb, NFTA_SET_ELEM_LIST_ELEMENTS);
4810 	if (nest == NULL)
4811 		goto nla_put_failure;
4812 
4813 	err = nf_tables_fill_setelem(skb, set, elem);
4814 	if (err < 0)
4815 		goto nla_put_failure;
4816 
4817 	nla_nest_end(skb, nest);
4818 
4819 	nlmsg_end(skb, nlh);
4820 	return 0;
4821 
4822 nla_put_failure:
4823 	nlmsg_trim(skb, nlh);
4824 	return -1;
4825 }
4826 
nft_setelem_parse_flags(const struct nft_set * set,const struct nlattr * attr,u32 * flags)4827 static int nft_setelem_parse_flags(const struct nft_set *set,
4828 				   const struct nlattr *attr, u32 *flags)
4829 {
4830 	if (attr == NULL)
4831 		return 0;
4832 
4833 	*flags = ntohl(nla_get_be32(attr));
4834 	if (*flags & ~NFT_SET_ELEM_INTERVAL_END)
4835 		return -EINVAL;
4836 	if (!(set->flags & NFT_SET_INTERVAL) &&
4837 	    *flags & NFT_SET_ELEM_INTERVAL_END)
4838 		return -EINVAL;
4839 
4840 	return 0;
4841 }
4842 
nft_setelem_parse_key(struct nft_ctx * ctx,struct nft_set * set,struct nft_data * key,struct nlattr * attr)4843 static int nft_setelem_parse_key(struct nft_ctx *ctx, struct nft_set *set,
4844 				 struct nft_data *key, struct nlattr *attr)
4845 {
4846 	struct nft_data_desc desc = {
4847 		.type	= NFT_DATA_VALUE,
4848 		.size	= NFT_DATA_VALUE_MAXLEN,
4849 		.len	= set->klen,
4850 	};
4851 
4852 	return nft_data_init(ctx, key, &desc, attr);
4853 }
4854 
nft_setelem_parse_data(struct nft_ctx * ctx,struct nft_set * set,struct nft_data_desc * desc,struct nft_data * data,struct nlattr * attr)4855 static int nft_setelem_parse_data(struct nft_ctx *ctx, struct nft_set *set,
4856 				  struct nft_data_desc *desc,
4857 				  struct nft_data *data,
4858 				  struct nlattr *attr)
4859 {
4860 	u32 dtype;
4861 
4862 	if (set->dtype == NFT_DATA_VERDICT)
4863 		dtype = NFT_DATA_VERDICT;
4864 	else
4865 		dtype = NFT_DATA_VALUE;
4866 
4867 	desc->type = dtype;
4868 	desc->size = NFT_DATA_VALUE_MAXLEN;
4869 	desc->len = set->dlen;
4870 	desc->flags = NFT_DATA_DESC_SETELEM;
4871 
4872 	return nft_data_init(ctx, data, desc, attr);
4873 }
4874 
nft_get_set_elem(struct nft_ctx * ctx,struct nft_set * set,const struct nlattr * attr)4875 static int nft_get_set_elem(struct nft_ctx *ctx, struct nft_set *set,
4876 			    const struct nlattr *attr)
4877 {
4878 	struct nlattr *nla[NFTA_SET_ELEM_MAX + 1];
4879 	struct nft_set_elem elem;
4880 	struct sk_buff *skb;
4881 	uint32_t flags = 0;
4882 	void *priv;
4883 	int err;
4884 
4885 	err = nla_parse_nested_deprecated(nla, NFTA_SET_ELEM_MAX, attr,
4886 					  nft_set_elem_policy, NULL);
4887 	if (err < 0)
4888 		return err;
4889 
4890 	if (!nla[NFTA_SET_ELEM_KEY])
4891 		return -EINVAL;
4892 
4893 	err = nft_setelem_parse_flags(set, nla[NFTA_SET_ELEM_FLAGS], &flags);
4894 	if (err < 0)
4895 		return err;
4896 
4897 	err = nft_setelem_parse_key(ctx, set, &elem.key.val,
4898 				    nla[NFTA_SET_ELEM_KEY]);
4899 	if (err < 0)
4900 		return err;
4901 
4902 	if (nla[NFTA_SET_ELEM_KEY_END]) {
4903 		err = nft_setelem_parse_key(ctx, set, &elem.key_end.val,
4904 					    nla[NFTA_SET_ELEM_KEY_END]);
4905 		if (err < 0)
4906 			return err;
4907 	}
4908 
4909 	priv = set->ops->get(ctx->net, set, &elem, flags);
4910 	if (IS_ERR(priv))
4911 		return PTR_ERR(priv);
4912 
4913 	elem.priv = priv;
4914 
4915 	err = -ENOMEM;
4916 	skb = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
4917 	if (skb == NULL)
4918 		return err;
4919 
4920 	err = nf_tables_fill_setelem_info(skb, ctx, ctx->seq, ctx->portid,
4921 					  NFT_MSG_NEWSETELEM, 0, set, &elem);
4922 	if (err < 0)
4923 		goto err_fill_setelem;
4924 
4925 	return nfnetlink_unicast(skb, ctx->net, ctx->portid);
4926 
4927 err_fill_setelem:
4928 	kfree_skb(skb);
4929 	return err;
4930 }
4931 
4932 /* called with rcu_read_lock held */
nf_tables_getsetelem(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)4933 static int nf_tables_getsetelem(struct net *net, struct sock *nlsk,
4934 				struct sk_buff *skb, const struct nlmsghdr *nlh,
4935 				const struct nlattr * const nla[],
4936 				struct netlink_ext_ack *extack)
4937 {
4938 	u8 genmask = nft_genmask_cur(net);
4939 	struct nft_set *set;
4940 	struct nlattr *attr;
4941 	struct nft_ctx ctx;
4942 	int rem, err = 0;
4943 
4944 	err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, extack,
4945 					 genmask);
4946 	if (err < 0)
4947 		return err;
4948 
4949 	set = nft_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET], genmask);
4950 	if (IS_ERR(set))
4951 		return PTR_ERR(set);
4952 
4953 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
4954 		struct netlink_dump_control c = {
4955 			.start = nf_tables_dump_set_start,
4956 			.dump = nf_tables_dump_set,
4957 			.done = nf_tables_dump_set_done,
4958 			.module = THIS_MODULE,
4959 		};
4960 		struct nft_set_dump_ctx dump_ctx = {
4961 			.set = set,
4962 			.ctx = ctx,
4963 		};
4964 
4965 		c.data = &dump_ctx;
4966 		return nft_netlink_dump_start_rcu(nlsk, skb, nlh, &c);
4967 	}
4968 
4969 	if (!nla[NFTA_SET_ELEM_LIST_ELEMENTS])
4970 		return -EINVAL;
4971 
4972 	nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) {
4973 		err = nft_get_set_elem(&ctx, set, attr);
4974 		if (err < 0)
4975 			break;
4976 	}
4977 
4978 	return err;
4979 }
4980 
nf_tables_setelem_notify(const struct nft_ctx * ctx,const struct nft_set * set,const struct nft_set_elem * elem,int event,u16 flags)4981 static void nf_tables_setelem_notify(const struct nft_ctx *ctx,
4982 				     const struct nft_set *set,
4983 				     const struct nft_set_elem *elem,
4984 				     int event, u16 flags)
4985 {
4986 	struct net *net = ctx->net;
4987 	u32 portid = ctx->portid;
4988 	struct sk_buff *skb;
4989 	int err;
4990 
4991 	if (!ctx->report && !nfnetlink_has_listeners(net, NFNLGRP_NFTABLES))
4992 		return;
4993 
4994 	skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
4995 	if (skb == NULL)
4996 		goto err;
4997 
4998 	err = nf_tables_fill_setelem_info(skb, ctx, 0, portid, event, flags,
4999 					  set, elem);
5000 	if (err < 0) {
5001 		kfree_skb(skb);
5002 		goto err;
5003 	}
5004 
5005 	nft_notify_enqueue(skb, ctx->report, &ctx->net->nft.notify_list);
5006 	return;
5007 err:
5008 	nfnetlink_set_err(net, portid, NFNLGRP_NFTABLES, -ENOBUFS);
5009 }
5010 
nft_trans_elem_alloc(struct nft_ctx * ctx,int msg_type,struct nft_set * set)5011 static struct nft_trans *nft_trans_elem_alloc(struct nft_ctx *ctx,
5012 					      int msg_type,
5013 					      struct nft_set *set)
5014 {
5015 	struct nft_trans *trans;
5016 
5017 	trans = nft_trans_alloc(ctx, msg_type, sizeof(struct nft_trans_elem));
5018 	if (trans == NULL)
5019 		return NULL;
5020 
5021 	nft_trans_elem_set(trans) = set;
5022 	return trans;
5023 }
5024 
nft_set_elem_expr_alloc(const struct nft_ctx * ctx,const struct nft_set * set,const struct nlattr * attr)5025 struct nft_expr *nft_set_elem_expr_alloc(const struct nft_ctx *ctx,
5026 					 const struct nft_set *set,
5027 					 const struct nlattr *attr)
5028 {
5029 	struct nft_expr *expr;
5030 	int err;
5031 
5032 	expr = nft_expr_init(ctx, attr);
5033 	if (IS_ERR(expr))
5034 		return expr;
5035 
5036 	err = -EOPNOTSUPP;
5037 	if (expr->ops->type->flags & NFT_EXPR_GC) {
5038 		if (set->flags & NFT_SET_TIMEOUT)
5039 			goto err_set_elem_expr;
5040 		if (!set->ops->gc_init)
5041 			goto err_set_elem_expr;
5042 		set->ops->gc_init(set);
5043 	}
5044 
5045 	return expr;
5046 
5047 err_set_elem_expr:
5048 	nft_expr_destroy(ctx, expr);
5049 	return ERR_PTR(err);
5050 }
5051 
nft_set_elem_init(const struct nft_set * set,const struct nft_set_ext_tmpl * tmpl,const u32 * key,const u32 * key_end,const u32 * data,u64 timeout,u64 expiration,gfp_t gfp)5052 void *nft_set_elem_init(const struct nft_set *set,
5053 			const struct nft_set_ext_tmpl *tmpl,
5054 			const u32 *key, const u32 *key_end,
5055 			const u32 *data, u64 timeout, u64 expiration, gfp_t gfp)
5056 {
5057 	struct nft_set_ext *ext;
5058 	void *elem;
5059 
5060 	elem = kzalloc(set->ops->elemsize + tmpl->len, gfp);
5061 	if (elem == NULL)
5062 		return NULL;
5063 
5064 	ext = nft_set_elem_ext(set, elem);
5065 	nft_set_ext_init(ext, tmpl);
5066 
5067 	memcpy(nft_set_ext_key(ext), key, set->klen);
5068 	if (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END))
5069 		memcpy(nft_set_ext_key_end(ext), key_end, set->klen);
5070 	if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA))
5071 		memcpy(nft_set_ext_data(ext), data, set->dlen);
5072 	if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION)) {
5073 		*nft_set_ext_expiration(ext) = get_jiffies_64() + expiration;
5074 		if (expiration == 0)
5075 			*nft_set_ext_expiration(ext) += timeout;
5076 	}
5077 	if (nft_set_ext_exists(ext, NFT_SET_EXT_TIMEOUT))
5078 		*nft_set_ext_timeout(ext) = timeout;
5079 
5080 	return elem;
5081 }
5082 
nft_set_elem_expr_destroy(const struct nft_ctx * ctx,struct nft_expr * expr)5083 static void nft_set_elem_expr_destroy(const struct nft_ctx *ctx,
5084 				      struct nft_expr *expr)
5085 {
5086 	if (expr->ops->destroy_clone) {
5087 		expr->ops->destroy_clone(ctx, expr);
5088 		module_put(expr->ops->type->owner);
5089 	} else {
5090 		nf_tables_expr_destroy(ctx, expr);
5091 	}
5092 }
5093 
nft_set_elem_destroy(const struct nft_set * set,void * elem,bool destroy_expr)5094 void nft_set_elem_destroy(const struct nft_set *set, void *elem,
5095 			  bool destroy_expr)
5096 {
5097 	struct nft_set_ext *ext = nft_set_elem_ext(set, elem);
5098 	struct nft_ctx ctx = {
5099 		.net	= read_pnet(&set->net),
5100 		.family	= set->table->family,
5101 	};
5102 
5103 	nft_data_release(nft_set_ext_key(ext), NFT_DATA_VALUE);
5104 	if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA))
5105 		nft_data_release(nft_set_ext_data(ext), set->dtype);
5106 	if (destroy_expr && nft_set_ext_exists(ext, NFT_SET_EXT_EXPR))
5107 		nft_set_elem_expr_destroy(&ctx, nft_set_ext_expr(ext));
5108 
5109 	if (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF))
5110 		(*nft_set_ext_obj(ext))->use--;
5111 	kfree(elem);
5112 }
5113 EXPORT_SYMBOL_GPL(nft_set_elem_destroy);
5114 
5115 /* Only called from commit path, nft_set_elem_deactivate() already deals with
5116  * the refcounting from the preparation phase.
5117  */
nf_tables_set_elem_destroy(const struct nft_ctx * ctx,const struct nft_set * set,void * elem)5118 static void nf_tables_set_elem_destroy(const struct nft_ctx *ctx,
5119 				       const struct nft_set *set, void *elem)
5120 {
5121 	struct nft_set_ext *ext = nft_set_elem_ext(set, elem);
5122 
5123 	if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPR))
5124 		nft_set_elem_expr_destroy(ctx, nft_set_ext_expr(ext));
5125 
5126 	kfree(elem);
5127 }
5128 
nft_set_elem_expr_setup(struct nft_ctx * ctx,const struct nft_set_ext * ext,struct nft_expr * expr)5129 static int nft_set_elem_expr_setup(struct nft_ctx *ctx,
5130 				   const struct nft_set_ext *ext,
5131 				   struct nft_expr *expr)
5132 {
5133 	struct nft_expr *elem_expr = nft_set_ext_expr(ext);
5134 	int err;
5135 
5136 	if (expr == NULL)
5137 		return 0;
5138 
5139 	err = nft_expr_clone(elem_expr, expr);
5140 	if (err < 0)
5141 		return -ENOMEM;
5142 
5143 	nft_expr_destroy(ctx, expr);
5144 	return 0;
5145 }
5146 
nft_add_set_elem(struct nft_ctx * ctx,struct nft_set * set,const struct nlattr * attr,u32 nlmsg_flags)5147 static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
5148 			    const struct nlattr *attr, u32 nlmsg_flags)
5149 {
5150 	struct nlattr *nla[NFTA_SET_ELEM_MAX + 1];
5151 	u8 genmask = nft_genmask_next(ctx->net);
5152 	struct nft_set_ext_tmpl tmpl;
5153 	struct nft_set_ext *ext, *ext2;
5154 	struct nft_set_elem elem;
5155 	struct nft_set_binding *binding;
5156 	struct nft_object *obj = NULL;
5157 	struct nft_expr *expr = NULL;
5158 	struct nft_userdata *udata;
5159 	struct nft_data_desc desc;
5160 	enum nft_registers dreg;
5161 	struct nft_trans *trans;
5162 	u32 flags = 0;
5163 	u64 timeout;
5164 	u64 expiration;
5165 	u8 ulen;
5166 	int err;
5167 
5168 	err = nla_parse_nested_deprecated(nla, NFTA_SET_ELEM_MAX, attr,
5169 					  nft_set_elem_policy, NULL);
5170 	if (err < 0)
5171 		return err;
5172 
5173 	if (nla[NFTA_SET_ELEM_KEY] == NULL)
5174 		return -EINVAL;
5175 
5176 	nft_set_ext_prepare(&tmpl);
5177 
5178 	err = nft_setelem_parse_flags(set, nla[NFTA_SET_ELEM_FLAGS], &flags);
5179 	if (err < 0)
5180 		return err;
5181 	if (flags != 0)
5182 		nft_set_ext_add(&tmpl, NFT_SET_EXT_FLAGS);
5183 
5184 	if (set->flags & NFT_SET_MAP) {
5185 		if (nla[NFTA_SET_ELEM_DATA] == NULL &&
5186 		    !(flags & NFT_SET_ELEM_INTERVAL_END))
5187 			return -EINVAL;
5188 	} else {
5189 		if (nla[NFTA_SET_ELEM_DATA] != NULL)
5190 			return -EINVAL;
5191 	}
5192 
5193 	if (set->flags & NFT_SET_OBJECT) {
5194 		if (!nla[NFTA_SET_ELEM_OBJREF] &&
5195 		    !(flags & NFT_SET_ELEM_INTERVAL_END))
5196 			return -EINVAL;
5197 	} else {
5198 		if (nla[NFTA_SET_ELEM_OBJREF])
5199 			return -EINVAL;
5200 	}
5201 
5202 	if ((flags & NFT_SET_ELEM_INTERVAL_END) &&
5203 	     (nla[NFTA_SET_ELEM_DATA] ||
5204 	      nla[NFTA_SET_ELEM_OBJREF] ||
5205 	      nla[NFTA_SET_ELEM_TIMEOUT] ||
5206 	      nla[NFTA_SET_ELEM_EXPIRATION] ||
5207 	      nla[NFTA_SET_ELEM_USERDATA] ||
5208 	      nla[NFTA_SET_ELEM_EXPR]))
5209 		return -EINVAL;
5210 
5211 	timeout = 0;
5212 	if (nla[NFTA_SET_ELEM_TIMEOUT] != NULL) {
5213 		if (!(set->flags & NFT_SET_TIMEOUT))
5214 			return -EINVAL;
5215 		err = nf_msecs_to_jiffies64(nla[NFTA_SET_ELEM_TIMEOUT],
5216 					    &timeout);
5217 		if (err)
5218 			return err;
5219 	} else if (set->flags & NFT_SET_TIMEOUT) {
5220 		timeout = set->timeout;
5221 	}
5222 
5223 	expiration = 0;
5224 	if (nla[NFTA_SET_ELEM_EXPIRATION] != NULL) {
5225 		if (!(set->flags & NFT_SET_TIMEOUT))
5226 			return -EINVAL;
5227 		err = nf_msecs_to_jiffies64(nla[NFTA_SET_ELEM_EXPIRATION],
5228 					    &expiration);
5229 		if (err)
5230 			return err;
5231 	}
5232 
5233 	if (nla[NFTA_SET_ELEM_EXPR] != NULL) {
5234 		expr = nft_set_elem_expr_alloc(ctx, set,
5235 					       nla[NFTA_SET_ELEM_EXPR]);
5236 		if (IS_ERR(expr))
5237 			return PTR_ERR(expr);
5238 
5239 		err = -EOPNOTSUPP;
5240 		if (set->expr && set->expr->ops != expr->ops)
5241 			goto err_set_elem_expr;
5242 	} else if (set->expr) {
5243 		expr = kzalloc(set->expr->ops->size, GFP_KERNEL);
5244 		if (!expr)
5245 			return -ENOMEM;
5246 
5247 		err = nft_expr_clone(expr, set->expr);
5248 		if (err < 0)
5249 			goto err_set_elem_expr;
5250 	}
5251 
5252 	err = nft_setelem_parse_key(ctx, set, &elem.key.val,
5253 				    nla[NFTA_SET_ELEM_KEY]);
5254 	if (err < 0)
5255 		goto err_set_elem_expr;
5256 
5257 	nft_set_ext_add_length(&tmpl, NFT_SET_EXT_KEY, set->klen);
5258 
5259 	if (nla[NFTA_SET_ELEM_KEY_END]) {
5260 		err = nft_setelem_parse_key(ctx, set, &elem.key_end.val,
5261 					    nla[NFTA_SET_ELEM_KEY_END]);
5262 		if (err < 0)
5263 			goto err_parse_key;
5264 
5265 		nft_set_ext_add_length(&tmpl, NFT_SET_EXT_KEY_END, set->klen);
5266 	}
5267 
5268 	if (timeout > 0) {
5269 		nft_set_ext_add(&tmpl, NFT_SET_EXT_EXPIRATION);
5270 		if (timeout != set->timeout)
5271 			nft_set_ext_add(&tmpl, NFT_SET_EXT_TIMEOUT);
5272 	}
5273 
5274 	if (expr)
5275 		nft_set_ext_add_length(&tmpl, NFT_SET_EXT_EXPR,
5276 				       expr->ops->size);
5277 
5278 	if (nla[NFTA_SET_ELEM_OBJREF] != NULL) {
5279 		obj = nft_obj_lookup(ctx->net, ctx->table,
5280 				     nla[NFTA_SET_ELEM_OBJREF],
5281 				     set->objtype, genmask);
5282 		if (IS_ERR(obj)) {
5283 			err = PTR_ERR(obj);
5284 			goto err_parse_key_end;
5285 		}
5286 		nft_set_ext_add(&tmpl, NFT_SET_EXT_OBJREF);
5287 	}
5288 
5289 	if (nla[NFTA_SET_ELEM_DATA] != NULL) {
5290 		err = nft_setelem_parse_data(ctx, set, &desc, &elem.data.val,
5291 					     nla[NFTA_SET_ELEM_DATA]);
5292 		if (err < 0)
5293 			goto err_parse_key_end;
5294 
5295 		dreg = nft_type_to_reg(set->dtype);
5296 		list_for_each_entry(binding, &set->bindings, list) {
5297 			struct nft_ctx bind_ctx = {
5298 				.net	= ctx->net,
5299 				.family	= ctx->family,
5300 				.table	= ctx->table,
5301 				.chain	= (struct nft_chain *)binding->chain,
5302 			};
5303 
5304 			if (!(binding->flags & NFT_SET_MAP))
5305 				continue;
5306 
5307 			err = nft_validate_register_store(&bind_ctx, dreg,
5308 							  &elem.data.val,
5309 							  desc.type, desc.len);
5310 			if (err < 0)
5311 				goto err_parse_data;
5312 
5313 			if (desc.type == NFT_DATA_VERDICT &&
5314 			    (elem.data.val.verdict.code == NFT_GOTO ||
5315 			     elem.data.val.verdict.code == NFT_JUMP))
5316 				nft_validate_state_update(ctx->net,
5317 							  NFT_VALIDATE_NEED);
5318 		}
5319 
5320 		nft_set_ext_add_length(&tmpl, NFT_SET_EXT_DATA, desc.len);
5321 	}
5322 
5323 	/* The full maximum length of userdata can exceed the maximum
5324 	 * offset value (U8_MAX) for following extensions, therefor it
5325 	 * must be the last extension added.
5326 	 */
5327 	ulen = 0;
5328 	if (nla[NFTA_SET_ELEM_USERDATA] != NULL) {
5329 		ulen = nla_len(nla[NFTA_SET_ELEM_USERDATA]);
5330 		if (ulen > 0)
5331 			nft_set_ext_add_length(&tmpl, NFT_SET_EXT_USERDATA,
5332 					       ulen);
5333 	}
5334 
5335 	err = -ENOMEM;
5336 	elem.priv = nft_set_elem_init(set, &tmpl, elem.key.val.data,
5337 				      elem.key_end.val.data, elem.data.val.data,
5338 				      timeout, expiration, GFP_KERNEL);
5339 	if (elem.priv == NULL)
5340 		goto err_parse_data;
5341 
5342 	ext = nft_set_elem_ext(set, elem.priv);
5343 	if (flags)
5344 		*nft_set_ext_flags(ext) = flags;
5345 	if (ulen > 0) {
5346 		udata = nft_set_ext_userdata(ext);
5347 		udata->len = ulen - 1;
5348 		nla_memcpy(&udata->data, nla[NFTA_SET_ELEM_USERDATA], ulen);
5349 	}
5350 	if (obj) {
5351 		*nft_set_ext_obj(ext) = obj;
5352 		obj->use++;
5353 	}
5354 
5355 	err = nft_set_elem_expr_setup(ctx, ext, expr);
5356 	if (err < 0)
5357 		goto err_elem_expr;
5358 	expr = NULL;
5359 
5360 	trans = nft_trans_elem_alloc(ctx, NFT_MSG_NEWSETELEM, set);
5361 	if (trans == NULL) {
5362 		err = -ENOMEM;
5363 		goto err_elem_expr;
5364 	}
5365 
5366 	ext->genmask = nft_genmask_cur(ctx->net) | NFT_SET_ELEM_BUSY_MASK;
5367 	err = set->ops->insert(ctx->net, set, &elem, &ext2);
5368 	if (err) {
5369 		if (err == -EEXIST) {
5370 			if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA) ^
5371 			    nft_set_ext_exists(ext2, NFT_SET_EXT_DATA) ||
5372 			    nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF) ^
5373 			    nft_set_ext_exists(ext2, NFT_SET_EXT_OBJREF))
5374 				goto err_element_clash;
5375 			if ((nft_set_ext_exists(ext, NFT_SET_EXT_DATA) &&
5376 			     nft_set_ext_exists(ext2, NFT_SET_EXT_DATA) &&
5377 			     memcmp(nft_set_ext_data(ext),
5378 				    nft_set_ext_data(ext2), set->dlen) != 0) ||
5379 			    (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF) &&
5380 			     nft_set_ext_exists(ext2, NFT_SET_EXT_OBJREF) &&
5381 			     *nft_set_ext_obj(ext) != *nft_set_ext_obj(ext2)))
5382 				goto err_element_clash;
5383 			else if (!(nlmsg_flags & NLM_F_EXCL))
5384 				err = 0;
5385 		} else if (err == -ENOTEMPTY) {
5386 			/* ENOTEMPTY reports overlapping between this element
5387 			 * and an existing one.
5388 			 */
5389 			err = -EEXIST;
5390 		}
5391 		goto err_element_clash;
5392 	}
5393 
5394 	if (set->size &&
5395 	    !atomic_add_unless(&set->nelems, 1, set->size + set->ndeact)) {
5396 		err = -ENFILE;
5397 		goto err_set_full;
5398 	}
5399 
5400 	nft_trans_elem(trans) = elem;
5401 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
5402 	return 0;
5403 
5404 err_set_full:
5405 	set->ops->remove(ctx->net, set, &elem);
5406 err_element_clash:
5407 	kfree(trans);
5408 err_elem_expr:
5409 	if (obj)
5410 		obj->use--;
5411 
5412 	nf_tables_set_elem_destroy(ctx, set, elem.priv);
5413 err_parse_data:
5414 	if (nla[NFTA_SET_ELEM_DATA] != NULL)
5415 		nft_data_release(&elem.data.val, desc.type);
5416 err_parse_key_end:
5417 	nft_data_release(&elem.key_end.val, NFT_DATA_VALUE);
5418 err_parse_key:
5419 	nft_data_release(&elem.key.val, NFT_DATA_VALUE);
5420 err_set_elem_expr:
5421 	if (expr != NULL)
5422 		nft_expr_destroy(ctx, expr);
5423 
5424 	return err;
5425 }
5426 
nf_tables_newsetelem(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)5427 static int nf_tables_newsetelem(struct net *net, struct sock *nlsk,
5428 				struct sk_buff *skb, const struct nlmsghdr *nlh,
5429 				const struct nlattr * const nla[],
5430 				struct netlink_ext_ack *extack)
5431 {
5432 	u8 genmask = nft_genmask_next(net);
5433 	const struct nlattr *attr;
5434 	struct nft_set *set;
5435 	struct nft_ctx ctx;
5436 	int rem, err;
5437 
5438 	if (nla[NFTA_SET_ELEM_LIST_ELEMENTS] == NULL)
5439 		return -EINVAL;
5440 
5441 	err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, extack,
5442 					 genmask);
5443 	if (err < 0)
5444 		return err;
5445 
5446 	set = nft_set_lookup_global(net, ctx.table, nla[NFTA_SET_ELEM_LIST_SET],
5447 				    nla[NFTA_SET_ELEM_LIST_SET_ID], genmask);
5448 	if (IS_ERR(set))
5449 		return PTR_ERR(set);
5450 
5451 	if (!list_empty(&set->bindings) && set->flags & NFT_SET_CONSTANT)
5452 		return -EBUSY;
5453 
5454 	nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) {
5455 		err = nft_add_set_elem(&ctx, set, attr, nlh->nlmsg_flags);
5456 		if (err < 0)
5457 			return err;
5458 	}
5459 
5460 	if (net->nft.validate_state == NFT_VALIDATE_DO)
5461 		return nft_table_validate(net, ctx.table);
5462 
5463 	return 0;
5464 }
5465 
5466 /**
5467  *	nft_data_hold - hold a nft_data item
5468  *
5469  *	@data: struct nft_data to release
5470  *	@type: type of data
5471  *
5472  *	Hold a nft_data item. NFT_DATA_VALUE types can be silently discarded,
5473  *	NFT_DATA_VERDICT bumps the reference to chains in case of NFT_JUMP and
5474  *	NFT_GOTO verdicts. This function must be called on active data objects
5475  *	from the second phase of the commit protocol.
5476  */
nft_data_hold(const struct nft_data * data,enum nft_data_types type)5477 void nft_data_hold(const struct nft_data *data, enum nft_data_types type)
5478 {
5479 	struct nft_chain *chain;
5480 	struct nft_rule *rule;
5481 
5482 	if (type == NFT_DATA_VERDICT) {
5483 		switch (data->verdict.code) {
5484 		case NFT_JUMP:
5485 		case NFT_GOTO:
5486 			chain = data->verdict.chain;
5487 			chain->use++;
5488 
5489 			if (!nft_chain_is_bound(chain))
5490 				break;
5491 
5492 			chain->table->use++;
5493 			list_for_each_entry(rule, &chain->rules, list)
5494 				chain->use++;
5495 
5496 			nft_chain_add(chain->table, chain);
5497 			break;
5498 		}
5499 	}
5500 }
5501 
nft_set_elem_activate(const struct net * net,const struct nft_set * set,struct nft_set_elem * elem)5502 static void nft_set_elem_activate(const struct net *net,
5503 				  const struct nft_set *set,
5504 				  struct nft_set_elem *elem)
5505 {
5506 	const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
5507 
5508 	if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA))
5509 		nft_data_hold(nft_set_ext_data(ext), set->dtype);
5510 	if (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF))
5511 		(*nft_set_ext_obj(ext))->use++;
5512 }
5513 
nft_set_elem_deactivate(const struct net * net,const struct nft_set * set,struct nft_set_elem * elem)5514 static void nft_set_elem_deactivate(const struct net *net,
5515 				    const struct nft_set *set,
5516 				    struct nft_set_elem *elem)
5517 {
5518 	const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
5519 
5520 	if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA))
5521 		nft_data_release(nft_set_ext_data(ext), set->dtype);
5522 	if (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF))
5523 		(*nft_set_ext_obj(ext))->use--;
5524 }
5525 
nft_del_setelem(struct nft_ctx * ctx,struct nft_set * set,const struct nlattr * attr)5526 static int nft_del_setelem(struct nft_ctx *ctx, struct nft_set *set,
5527 			   const struct nlattr *attr)
5528 {
5529 	struct nlattr *nla[NFTA_SET_ELEM_MAX + 1];
5530 	struct nft_set_ext_tmpl tmpl;
5531 	struct nft_set_elem elem;
5532 	struct nft_set_ext *ext;
5533 	struct nft_trans *trans;
5534 	u32 flags = 0;
5535 	void *priv;
5536 	int err;
5537 
5538 	err = nla_parse_nested_deprecated(nla, NFTA_SET_ELEM_MAX, attr,
5539 					  nft_set_elem_policy, NULL);
5540 	if (err < 0)
5541 		return err;
5542 
5543 	if (nla[NFTA_SET_ELEM_KEY] == NULL)
5544 		return -EINVAL;
5545 
5546 	nft_set_ext_prepare(&tmpl);
5547 
5548 	err = nft_setelem_parse_flags(set, nla[NFTA_SET_ELEM_FLAGS], &flags);
5549 	if (err < 0)
5550 		return err;
5551 	if (flags != 0)
5552 		nft_set_ext_add(&tmpl, NFT_SET_EXT_FLAGS);
5553 
5554 	err = nft_setelem_parse_key(ctx, set, &elem.key.val,
5555 				    nla[NFTA_SET_ELEM_KEY]);
5556 	if (err < 0)
5557 		return err;
5558 
5559 	nft_set_ext_add_length(&tmpl, NFT_SET_EXT_KEY, set->klen);
5560 
5561 	if (nla[NFTA_SET_ELEM_KEY_END]) {
5562 		err = nft_setelem_parse_key(ctx, set, &elem.key_end.val,
5563 					    nla[NFTA_SET_ELEM_KEY_END]);
5564 		if (err < 0)
5565 			return err;
5566 
5567 		nft_set_ext_add_length(&tmpl, NFT_SET_EXT_KEY_END, set->klen);
5568 	}
5569 
5570 	err = -ENOMEM;
5571 	elem.priv = nft_set_elem_init(set, &tmpl, elem.key.val.data,
5572 				      elem.key_end.val.data, NULL, 0, 0,
5573 				      GFP_KERNEL);
5574 	if (elem.priv == NULL)
5575 		goto fail_elem;
5576 
5577 	ext = nft_set_elem_ext(set, elem.priv);
5578 	if (flags)
5579 		*nft_set_ext_flags(ext) = flags;
5580 
5581 	trans = nft_trans_elem_alloc(ctx, NFT_MSG_DELSETELEM, set);
5582 	if (trans == NULL)
5583 		goto fail_trans;
5584 
5585 	priv = set->ops->deactivate(ctx->net, set, &elem);
5586 	if (priv == NULL) {
5587 		err = -ENOENT;
5588 		goto fail_ops;
5589 	}
5590 	kfree(elem.priv);
5591 	elem.priv = priv;
5592 
5593 	nft_set_elem_deactivate(ctx->net, set, &elem);
5594 
5595 	nft_trans_elem(trans) = elem;
5596 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
5597 	return 0;
5598 
5599 fail_ops:
5600 	kfree(trans);
5601 fail_trans:
5602 	kfree(elem.priv);
5603 fail_elem:
5604 	nft_data_release(&elem.key.val, NFT_DATA_VALUE);
5605 	return err;
5606 }
5607 
nft_flush_set(const struct nft_ctx * ctx,struct nft_set * set,const struct nft_set_iter * iter,struct nft_set_elem * elem)5608 static int nft_flush_set(const struct nft_ctx *ctx,
5609 			 struct nft_set *set,
5610 			 const struct nft_set_iter *iter,
5611 			 struct nft_set_elem *elem)
5612 {
5613 	struct nft_trans *trans;
5614 	int err;
5615 
5616 	trans = nft_trans_alloc_gfp(ctx, NFT_MSG_DELSETELEM,
5617 				    sizeof(struct nft_trans_elem), GFP_ATOMIC);
5618 	if (!trans)
5619 		return -ENOMEM;
5620 
5621 	if (!set->ops->flush(ctx->net, set, elem->priv)) {
5622 		err = -ENOENT;
5623 		goto err1;
5624 	}
5625 	set->ndeact++;
5626 
5627 	nft_set_elem_deactivate(ctx->net, set, elem);
5628 	nft_trans_elem_set(trans) = set;
5629 	nft_trans_elem(trans) = *elem;
5630 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
5631 
5632 	return 0;
5633 err1:
5634 	kfree(trans);
5635 	return err;
5636 }
5637 
nf_tables_delsetelem(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)5638 static int nf_tables_delsetelem(struct net *net, struct sock *nlsk,
5639 				struct sk_buff *skb, const struct nlmsghdr *nlh,
5640 				const struct nlattr * const nla[],
5641 				struct netlink_ext_ack *extack)
5642 {
5643 	u8 genmask = nft_genmask_next(net);
5644 	const struct nlattr *attr;
5645 	struct nft_set *set;
5646 	struct nft_ctx ctx;
5647 	int rem, err = 0;
5648 
5649 	err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, extack,
5650 					 genmask);
5651 	if (err < 0)
5652 		return err;
5653 
5654 	set = nft_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET], genmask);
5655 	if (IS_ERR(set))
5656 		return PTR_ERR(set);
5657 	if (!list_empty(&set->bindings) && set->flags & NFT_SET_CONSTANT)
5658 		return -EBUSY;
5659 
5660 	if (nla[NFTA_SET_ELEM_LIST_ELEMENTS] == NULL) {
5661 		struct nft_set_iter iter = {
5662 			.genmask	= genmask,
5663 			.fn		= nft_flush_set,
5664 		};
5665 		set->ops->walk(&ctx, set, &iter);
5666 
5667 		return iter.err;
5668 	}
5669 
5670 	nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) {
5671 		err = nft_del_setelem(&ctx, set, attr);
5672 		if (err < 0)
5673 			break;
5674 
5675 		set->ndeact++;
5676 	}
5677 	return err;
5678 }
5679 
nft_set_gc_batch_release(struct rcu_head * rcu)5680 void nft_set_gc_batch_release(struct rcu_head *rcu)
5681 {
5682 	struct nft_set_gc_batch *gcb;
5683 	unsigned int i;
5684 
5685 	gcb = container_of(rcu, struct nft_set_gc_batch, head.rcu);
5686 	for (i = 0; i < gcb->head.cnt; i++)
5687 		nft_set_elem_destroy(gcb->head.set, gcb->elems[i], true);
5688 	kfree(gcb);
5689 }
5690 
nft_set_gc_batch_alloc(const struct nft_set * set,gfp_t gfp)5691 struct nft_set_gc_batch *nft_set_gc_batch_alloc(const struct nft_set *set,
5692 						gfp_t gfp)
5693 {
5694 	struct nft_set_gc_batch *gcb;
5695 
5696 	gcb = kzalloc(sizeof(*gcb), gfp);
5697 	if (gcb == NULL)
5698 		return gcb;
5699 	gcb->head.set = set;
5700 	return gcb;
5701 }
5702 
5703 /*
5704  * Stateful objects
5705  */
5706 
5707 /**
5708  *	nft_register_obj- register nf_tables stateful object type
5709  *	@obj_type: object type
5710  *
5711  *	Registers the object type for use with nf_tables. Returns zero on
5712  *	success or a negative errno code otherwise.
5713  */
nft_register_obj(struct nft_object_type * obj_type)5714 int nft_register_obj(struct nft_object_type *obj_type)
5715 {
5716 	if (obj_type->type == NFT_OBJECT_UNSPEC)
5717 		return -EINVAL;
5718 
5719 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
5720 	list_add_rcu(&obj_type->list, &nf_tables_objects);
5721 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
5722 	return 0;
5723 }
5724 EXPORT_SYMBOL_GPL(nft_register_obj);
5725 
5726 /**
5727  *	nft_unregister_obj - unregister nf_tables object type
5728  *	@obj_type: object type
5729  *
5730  * 	Unregisters the object type for use with nf_tables.
5731  */
nft_unregister_obj(struct nft_object_type * obj_type)5732 void nft_unregister_obj(struct nft_object_type *obj_type)
5733 {
5734 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
5735 	list_del_rcu(&obj_type->list);
5736 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
5737 }
5738 EXPORT_SYMBOL_GPL(nft_unregister_obj);
5739 
nft_obj_lookup(const struct net * net,const struct nft_table * table,const struct nlattr * nla,u32 objtype,u8 genmask)5740 struct nft_object *nft_obj_lookup(const struct net *net,
5741 				  const struct nft_table *table,
5742 				  const struct nlattr *nla, u32 objtype,
5743 				  u8 genmask)
5744 {
5745 	struct nft_object_hash_key k = { .table = table };
5746 	char search[NFT_OBJ_MAXNAMELEN];
5747 	struct rhlist_head *tmp, *list;
5748 	struct nft_object *obj;
5749 
5750 	nla_strlcpy(search, nla, sizeof(search));
5751 	k.name = search;
5752 
5753 	WARN_ON_ONCE(!rcu_read_lock_held() &&
5754 		     !lockdep_commit_lock_is_held(net));
5755 
5756 	rcu_read_lock();
5757 	list = rhltable_lookup(&nft_objname_ht, &k, nft_objname_ht_params);
5758 	if (!list)
5759 		goto out;
5760 
5761 	rhl_for_each_entry_rcu(obj, tmp, list, rhlhead) {
5762 		if (objtype == obj->ops->type->type &&
5763 		    nft_active_genmask(obj, genmask)) {
5764 			rcu_read_unlock();
5765 			return obj;
5766 		}
5767 	}
5768 out:
5769 	rcu_read_unlock();
5770 	return ERR_PTR(-ENOENT);
5771 }
5772 EXPORT_SYMBOL_GPL(nft_obj_lookup);
5773 
nft_obj_lookup_byhandle(const struct nft_table * table,const struct nlattr * nla,u32 objtype,u8 genmask)5774 static struct nft_object *nft_obj_lookup_byhandle(const struct nft_table *table,
5775 						  const struct nlattr *nla,
5776 						  u32 objtype, u8 genmask)
5777 {
5778 	struct nft_object *obj;
5779 
5780 	list_for_each_entry(obj, &table->objects, list) {
5781 		if (be64_to_cpu(nla_get_be64(nla)) == obj->handle &&
5782 		    objtype == obj->ops->type->type &&
5783 		    nft_active_genmask(obj, genmask))
5784 			return obj;
5785 	}
5786 	return ERR_PTR(-ENOENT);
5787 }
5788 
5789 static const struct nla_policy nft_obj_policy[NFTA_OBJ_MAX + 1] = {
5790 	[NFTA_OBJ_TABLE]	= { .type = NLA_STRING,
5791 				    .len = NFT_TABLE_MAXNAMELEN - 1 },
5792 	[NFTA_OBJ_NAME]		= { .type = NLA_STRING,
5793 				    .len = NFT_OBJ_MAXNAMELEN - 1 },
5794 	[NFTA_OBJ_TYPE]		= { .type = NLA_U32 },
5795 	[NFTA_OBJ_DATA]		= { .type = NLA_NESTED },
5796 	[NFTA_OBJ_HANDLE]	= { .type = NLA_U64},
5797 	[NFTA_OBJ_USERDATA]	= { .type = NLA_BINARY,
5798 				    .len = NFT_USERDATA_MAXLEN },
5799 };
5800 
nft_obj_init(const struct nft_ctx * ctx,const struct nft_object_type * type,const struct nlattr * attr)5801 static struct nft_object *nft_obj_init(const struct nft_ctx *ctx,
5802 				       const struct nft_object_type *type,
5803 				       const struct nlattr *attr)
5804 {
5805 	struct nlattr **tb;
5806 	const struct nft_object_ops *ops;
5807 	struct nft_object *obj;
5808 	int err = -ENOMEM;
5809 
5810 	tb = kmalloc_array(type->maxattr + 1, sizeof(*tb), GFP_KERNEL);
5811 	if (!tb)
5812 		goto err1;
5813 
5814 	if (attr) {
5815 		err = nla_parse_nested_deprecated(tb, type->maxattr, attr,
5816 						  type->policy, NULL);
5817 		if (err < 0)
5818 			goto err2;
5819 	} else {
5820 		memset(tb, 0, sizeof(tb[0]) * (type->maxattr + 1));
5821 	}
5822 
5823 	if (type->select_ops) {
5824 		ops = type->select_ops(ctx, (const struct nlattr * const *)tb);
5825 		if (IS_ERR(ops)) {
5826 			err = PTR_ERR(ops);
5827 			goto err2;
5828 		}
5829 	} else {
5830 		ops = type->ops;
5831 	}
5832 
5833 	err = -ENOMEM;
5834 	obj = kzalloc(sizeof(*obj) + ops->size, GFP_KERNEL);
5835 	if (!obj)
5836 		goto err2;
5837 
5838 	err = ops->init(ctx, (const struct nlattr * const *)tb, obj);
5839 	if (err < 0)
5840 		goto err3;
5841 
5842 	obj->ops = ops;
5843 
5844 	kfree(tb);
5845 	return obj;
5846 err3:
5847 	kfree(obj);
5848 err2:
5849 	kfree(tb);
5850 err1:
5851 	return ERR_PTR(err);
5852 }
5853 
nft_object_dump(struct sk_buff * skb,unsigned int attr,struct nft_object * obj,bool reset)5854 static int nft_object_dump(struct sk_buff *skb, unsigned int attr,
5855 			   struct nft_object *obj, bool reset)
5856 {
5857 	struct nlattr *nest;
5858 
5859 	nest = nla_nest_start_noflag(skb, attr);
5860 	if (!nest)
5861 		goto nla_put_failure;
5862 	if (obj->ops->dump(skb, obj, reset) < 0)
5863 		goto nla_put_failure;
5864 	nla_nest_end(skb, nest);
5865 	return 0;
5866 
5867 nla_put_failure:
5868 	return -1;
5869 }
5870 
__nft_obj_type_get(u32 objtype)5871 static const struct nft_object_type *__nft_obj_type_get(u32 objtype)
5872 {
5873 	const struct nft_object_type *type;
5874 
5875 	list_for_each_entry(type, &nf_tables_objects, list) {
5876 		if (objtype == type->type)
5877 			return type;
5878 	}
5879 	return NULL;
5880 }
5881 
5882 static const struct nft_object_type *
nft_obj_type_get(struct net * net,u32 objtype)5883 nft_obj_type_get(struct net *net, u32 objtype)
5884 {
5885 	const struct nft_object_type *type;
5886 
5887 	type = __nft_obj_type_get(objtype);
5888 	if (type != NULL && try_module_get(type->owner))
5889 		return type;
5890 
5891 	lockdep_nfnl_nft_mutex_not_held();
5892 #ifdef CONFIG_MODULES
5893 	if (type == NULL) {
5894 		if (nft_request_module(net, "nft-obj-%u", objtype) == -EAGAIN)
5895 			return ERR_PTR(-EAGAIN);
5896 	}
5897 #endif
5898 	return ERR_PTR(-ENOENT);
5899 }
5900 
nf_tables_updobj(const struct nft_ctx * ctx,const struct nft_object_type * type,const struct nlattr * attr,struct nft_object * obj)5901 static int nf_tables_updobj(const struct nft_ctx *ctx,
5902 			    const struct nft_object_type *type,
5903 			    const struct nlattr *attr,
5904 			    struct nft_object *obj)
5905 {
5906 	struct nft_object *newobj;
5907 	struct nft_trans *trans;
5908 	int err = -ENOMEM;
5909 
5910 	if (!try_module_get(type->owner))
5911 		return -ENOENT;
5912 
5913 	trans = nft_trans_alloc(ctx, NFT_MSG_NEWOBJ,
5914 				sizeof(struct nft_trans_obj));
5915 	if (!trans)
5916 		goto err_trans;
5917 
5918 	newobj = nft_obj_init(ctx, type, attr);
5919 	if (IS_ERR(newobj)) {
5920 		err = PTR_ERR(newobj);
5921 		goto err_free_trans;
5922 	}
5923 
5924 	nft_trans_obj(trans) = obj;
5925 	nft_trans_obj_update(trans) = true;
5926 	nft_trans_obj_newobj(trans) = newobj;
5927 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
5928 
5929 	return 0;
5930 
5931 err_free_trans:
5932 	kfree(trans);
5933 err_trans:
5934 	module_put(type->owner);
5935 	return err;
5936 }
5937 
nf_tables_newobj(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)5938 static int nf_tables_newobj(struct net *net, struct sock *nlsk,
5939 			    struct sk_buff *skb, const struct nlmsghdr *nlh,
5940 			    const struct nlattr * const nla[],
5941 			    struct netlink_ext_ack *extack)
5942 {
5943 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
5944 	const struct nft_object_type *type;
5945 	u8 genmask = nft_genmask_next(net);
5946 	int family = nfmsg->nfgen_family;
5947 	struct nft_table *table;
5948 	struct nft_object *obj;
5949 	struct nft_ctx ctx;
5950 	u32 objtype;
5951 	int err;
5952 
5953 	if (!nla[NFTA_OBJ_TYPE] ||
5954 	    !nla[NFTA_OBJ_NAME] ||
5955 	    !nla[NFTA_OBJ_DATA])
5956 		return -EINVAL;
5957 
5958 	table = nft_table_lookup(net, nla[NFTA_OBJ_TABLE], family, genmask);
5959 	if (IS_ERR(table)) {
5960 		NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_TABLE]);
5961 		return PTR_ERR(table);
5962 	}
5963 
5964 	objtype = ntohl(nla_get_be32(nla[NFTA_OBJ_TYPE]));
5965 	obj = nft_obj_lookup(net, table, nla[NFTA_OBJ_NAME], objtype, genmask);
5966 	if (IS_ERR(obj)) {
5967 		err = PTR_ERR(obj);
5968 		if (err != -ENOENT) {
5969 			NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_NAME]);
5970 			return err;
5971 		}
5972 	} else {
5973 		if (nlh->nlmsg_flags & NLM_F_EXCL) {
5974 			NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_NAME]);
5975 			return -EEXIST;
5976 		}
5977 		if (nlh->nlmsg_flags & NLM_F_REPLACE)
5978 			return -EOPNOTSUPP;
5979 
5980 		type = __nft_obj_type_get(objtype);
5981 		nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
5982 
5983 		return nf_tables_updobj(&ctx, type, nla[NFTA_OBJ_DATA], obj);
5984 	}
5985 
5986 	nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
5987 
5988 	type = nft_obj_type_get(net, objtype);
5989 	if (IS_ERR(type))
5990 		return PTR_ERR(type);
5991 
5992 	obj = nft_obj_init(&ctx, type, nla[NFTA_OBJ_DATA]);
5993 	if (IS_ERR(obj)) {
5994 		err = PTR_ERR(obj);
5995 		goto err_init;
5996 	}
5997 	obj->key.table = table;
5998 	obj->handle = nf_tables_alloc_handle(table);
5999 
6000 	obj->key.name = nla_strdup(nla[NFTA_OBJ_NAME], GFP_KERNEL);
6001 	if (!obj->key.name) {
6002 		err = -ENOMEM;
6003 		goto err_strdup;
6004 	}
6005 
6006 	if (nla[NFTA_OBJ_USERDATA]) {
6007 		obj->udata = nla_memdup(nla[NFTA_OBJ_USERDATA], GFP_KERNEL);
6008 		if (obj->udata == NULL)
6009 			goto err_userdata;
6010 
6011 		obj->udlen = nla_len(nla[NFTA_OBJ_USERDATA]);
6012 	}
6013 
6014 	err = nft_trans_obj_add(&ctx, NFT_MSG_NEWOBJ, obj);
6015 	if (err < 0)
6016 		goto err_trans;
6017 
6018 	err = rhltable_insert(&nft_objname_ht, &obj->rhlhead,
6019 			      nft_objname_ht_params);
6020 	if (err < 0)
6021 		goto err_obj_ht;
6022 
6023 	list_add_tail_rcu(&obj->list, &table->objects);
6024 	table->use++;
6025 	return 0;
6026 err_obj_ht:
6027 	/* queued in transaction log */
6028 	INIT_LIST_HEAD(&obj->list);
6029 	return err;
6030 err_trans:
6031 	kfree(obj->udata);
6032 err_userdata:
6033 	kfree(obj->key.name);
6034 err_strdup:
6035 	if (obj->ops->destroy)
6036 		obj->ops->destroy(&ctx, obj);
6037 	kfree(obj);
6038 err_init:
6039 	module_put(type->owner);
6040 	return err;
6041 }
6042 
nf_tables_fill_obj_info(struct sk_buff * skb,struct net * net,u32 portid,u32 seq,int event,u32 flags,int family,const struct nft_table * table,struct nft_object * obj,bool reset)6043 static int nf_tables_fill_obj_info(struct sk_buff *skb, struct net *net,
6044 				   u32 portid, u32 seq, int event, u32 flags,
6045 				   int family, const struct nft_table *table,
6046 				   struct nft_object *obj, bool reset)
6047 {
6048 	struct nlmsghdr *nlh;
6049 
6050 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
6051 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
6052 			   NFNETLINK_V0, nft_base_seq(net));
6053 	if (!nlh)
6054 		goto nla_put_failure;
6055 
6056 	if (nla_put_string(skb, NFTA_OBJ_TABLE, table->name) ||
6057 	    nla_put_string(skb, NFTA_OBJ_NAME, obj->key.name) ||
6058 	    nla_put_be32(skb, NFTA_OBJ_TYPE, htonl(obj->ops->type->type)) ||
6059 	    nla_put_be32(skb, NFTA_OBJ_USE, htonl(obj->use)) ||
6060 	    nft_object_dump(skb, NFTA_OBJ_DATA, obj, reset) ||
6061 	    nla_put_be64(skb, NFTA_OBJ_HANDLE, cpu_to_be64(obj->handle),
6062 			 NFTA_OBJ_PAD))
6063 		goto nla_put_failure;
6064 
6065 	if (obj->udata &&
6066 	    nla_put(skb, NFTA_OBJ_USERDATA, obj->udlen, obj->udata))
6067 		goto nla_put_failure;
6068 
6069 	nlmsg_end(skb, nlh);
6070 	return 0;
6071 
6072 nla_put_failure:
6073 	nlmsg_trim(skb, nlh);
6074 	return -1;
6075 }
6076 
6077 struct nft_obj_filter {
6078 	char		*table;
6079 	u32		type;
6080 };
6081 
nf_tables_dump_obj(struct sk_buff * skb,struct netlink_callback * cb)6082 static int nf_tables_dump_obj(struct sk_buff *skb, struct netlink_callback *cb)
6083 {
6084 	const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
6085 	const struct nft_table *table;
6086 	unsigned int idx = 0, s_idx = cb->args[0];
6087 	struct nft_obj_filter *filter = cb->data;
6088 	struct net *net = sock_net(skb->sk);
6089 	int family = nfmsg->nfgen_family;
6090 	struct nft_object *obj;
6091 	bool reset = false;
6092 
6093 	if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) == NFT_MSG_GETOBJ_RESET)
6094 		reset = true;
6095 
6096 	rcu_read_lock();
6097 	cb->seq = net->nft.base_seq;
6098 
6099 	list_for_each_entry_rcu(table, &net->nft.tables, list) {
6100 		if (family != NFPROTO_UNSPEC && family != table->family)
6101 			continue;
6102 
6103 		list_for_each_entry_rcu(obj, &table->objects, list) {
6104 			if (!nft_is_active(net, obj))
6105 				goto cont;
6106 			if (idx < s_idx)
6107 				goto cont;
6108 			if (idx > s_idx)
6109 				memset(&cb->args[1], 0,
6110 				       sizeof(cb->args) - sizeof(cb->args[0]));
6111 			if (filter && filter->table &&
6112 			    strcmp(filter->table, table->name))
6113 				goto cont;
6114 			if (filter &&
6115 			    filter->type != NFT_OBJECT_UNSPEC &&
6116 			    obj->ops->type->type != filter->type)
6117 				goto cont;
6118 			if (reset) {
6119 				char *buf = kasprintf(GFP_ATOMIC,
6120 						      "%s:%u",
6121 						      table->name,
6122 						      net->nft.base_seq);
6123 
6124 				audit_log_nfcfg(buf,
6125 						family,
6126 						obj->handle,
6127 						AUDIT_NFT_OP_OBJ_RESET,
6128 						GFP_ATOMIC);
6129 				kfree(buf);
6130 			}
6131 
6132 			if (nf_tables_fill_obj_info(skb, net, NETLINK_CB(cb->skb).portid,
6133 						    cb->nlh->nlmsg_seq,
6134 						    NFT_MSG_NEWOBJ,
6135 						    NLM_F_MULTI | NLM_F_APPEND,
6136 						    table->family, table,
6137 						    obj, reset) < 0)
6138 				goto done;
6139 
6140 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
6141 cont:
6142 			idx++;
6143 		}
6144 	}
6145 done:
6146 	rcu_read_unlock();
6147 
6148 	cb->args[0] = idx;
6149 	return skb->len;
6150 }
6151 
nf_tables_dump_obj_start(struct netlink_callback * cb)6152 static int nf_tables_dump_obj_start(struct netlink_callback *cb)
6153 {
6154 	const struct nlattr * const *nla = cb->data;
6155 	struct nft_obj_filter *filter = NULL;
6156 
6157 	if (nla[NFTA_OBJ_TABLE] || nla[NFTA_OBJ_TYPE]) {
6158 		filter = kzalloc(sizeof(*filter), GFP_ATOMIC);
6159 		if (!filter)
6160 			return -ENOMEM;
6161 
6162 		if (nla[NFTA_OBJ_TABLE]) {
6163 			filter->table = nla_strdup(nla[NFTA_OBJ_TABLE], GFP_ATOMIC);
6164 			if (!filter->table) {
6165 				kfree(filter);
6166 				return -ENOMEM;
6167 			}
6168 		}
6169 
6170 		if (nla[NFTA_OBJ_TYPE])
6171 			filter->type = ntohl(nla_get_be32(nla[NFTA_OBJ_TYPE]));
6172 	}
6173 
6174 	cb->data = filter;
6175 	return 0;
6176 }
6177 
nf_tables_dump_obj_done(struct netlink_callback * cb)6178 static int nf_tables_dump_obj_done(struct netlink_callback *cb)
6179 {
6180 	struct nft_obj_filter *filter = cb->data;
6181 
6182 	if (filter) {
6183 		kfree(filter->table);
6184 		kfree(filter);
6185 	}
6186 
6187 	return 0;
6188 }
6189 
6190 /* called with rcu_read_lock held */
nf_tables_getobj(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)6191 static int nf_tables_getobj(struct net *net, struct sock *nlsk,
6192 			    struct sk_buff *skb, const struct nlmsghdr *nlh,
6193 			    const struct nlattr * const nla[],
6194 			    struct netlink_ext_ack *extack)
6195 {
6196 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
6197 	u8 genmask = nft_genmask_cur(net);
6198 	int family = nfmsg->nfgen_family;
6199 	const struct nft_table *table;
6200 	struct nft_object *obj;
6201 	struct sk_buff *skb2;
6202 	bool reset = false;
6203 	u32 objtype;
6204 	int err;
6205 
6206 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
6207 		struct netlink_dump_control c = {
6208 			.start = nf_tables_dump_obj_start,
6209 			.dump = nf_tables_dump_obj,
6210 			.done = nf_tables_dump_obj_done,
6211 			.module = THIS_MODULE,
6212 			.data = (void *)nla,
6213 		};
6214 
6215 		return nft_netlink_dump_start_rcu(nlsk, skb, nlh, &c);
6216 	}
6217 
6218 	if (!nla[NFTA_OBJ_NAME] ||
6219 	    !nla[NFTA_OBJ_TYPE])
6220 		return -EINVAL;
6221 
6222 	table = nft_table_lookup(net, nla[NFTA_OBJ_TABLE], family, genmask);
6223 	if (IS_ERR(table)) {
6224 		NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_TABLE]);
6225 		return PTR_ERR(table);
6226 	}
6227 
6228 	objtype = ntohl(nla_get_be32(nla[NFTA_OBJ_TYPE]));
6229 	obj = nft_obj_lookup(net, table, nla[NFTA_OBJ_NAME], objtype, genmask);
6230 	if (IS_ERR(obj)) {
6231 		NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_NAME]);
6232 		return PTR_ERR(obj);
6233 	}
6234 
6235 	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
6236 	if (!skb2)
6237 		return -ENOMEM;
6238 
6239 	if (NFNL_MSG_TYPE(nlh->nlmsg_type) == NFT_MSG_GETOBJ_RESET)
6240 		reset = true;
6241 
6242 	if (reset) {
6243 		char *buf = kasprintf(GFP_ATOMIC, "%s:%u",
6244 				      table->name, net->nft.base_seq);
6245 
6246 		audit_log_nfcfg(buf,
6247 				family,
6248 				obj->handle,
6249 				AUDIT_NFT_OP_OBJ_RESET,
6250 				GFP_ATOMIC);
6251 		kfree(buf);
6252 	}
6253 
6254 	err = nf_tables_fill_obj_info(skb2, net, NETLINK_CB(skb).portid,
6255 				      nlh->nlmsg_seq, NFT_MSG_NEWOBJ, 0,
6256 				      family, table, obj, reset);
6257 	if (err < 0)
6258 		goto err_fill_obj_info;
6259 
6260 	return nfnetlink_unicast(skb2, net, NETLINK_CB(skb).portid);
6261 
6262 err_fill_obj_info:
6263 	kfree_skb(skb2);
6264 	return err;
6265 }
6266 
nft_obj_destroy(const struct nft_ctx * ctx,struct nft_object * obj)6267 static void nft_obj_destroy(const struct nft_ctx *ctx, struct nft_object *obj)
6268 {
6269 	if (obj->ops->destroy)
6270 		obj->ops->destroy(ctx, obj);
6271 
6272 	module_put(obj->ops->type->owner);
6273 	kfree(obj->key.name);
6274 	kfree(obj->udata);
6275 	kfree(obj);
6276 }
6277 
nf_tables_delobj(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)6278 static int nf_tables_delobj(struct net *net, struct sock *nlsk,
6279 			    struct sk_buff *skb, const struct nlmsghdr *nlh,
6280 			    const struct nlattr * const nla[],
6281 			    struct netlink_ext_ack *extack)
6282 {
6283 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
6284 	u8 genmask = nft_genmask_next(net);
6285 	int family = nfmsg->nfgen_family;
6286 	const struct nlattr *attr;
6287 	struct nft_table *table;
6288 	struct nft_object *obj;
6289 	struct nft_ctx ctx;
6290 	u32 objtype;
6291 
6292 	if (!nla[NFTA_OBJ_TYPE] ||
6293 	    (!nla[NFTA_OBJ_NAME] && !nla[NFTA_OBJ_HANDLE]))
6294 		return -EINVAL;
6295 
6296 	table = nft_table_lookup(net, nla[NFTA_OBJ_TABLE], family, genmask);
6297 	if (IS_ERR(table)) {
6298 		NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_TABLE]);
6299 		return PTR_ERR(table);
6300 	}
6301 
6302 	objtype = ntohl(nla_get_be32(nla[NFTA_OBJ_TYPE]));
6303 	if (nla[NFTA_OBJ_HANDLE]) {
6304 		attr = nla[NFTA_OBJ_HANDLE];
6305 		obj = nft_obj_lookup_byhandle(table, attr, objtype, genmask);
6306 	} else {
6307 		attr = nla[NFTA_OBJ_NAME];
6308 		obj = nft_obj_lookup(net, table, attr, objtype, genmask);
6309 	}
6310 
6311 	if (IS_ERR(obj)) {
6312 		NL_SET_BAD_ATTR(extack, attr);
6313 		return PTR_ERR(obj);
6314 	}
6315 	if (obj->use > 0) {
6316 		NL_SET_BAD_ATTR(extack, attr);
6317 		return -EBUSY;
6318 	}
6319 
6320 	nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
6321 
6322 	return nft_delobj(&ctx, obj);
6323 }
6324 
nft_obj_notify(struct net * net,const struct nft_table * table,struct nft_object * obj,u32 portid,u32 seq,int event,int family,int report,gfp_t gfp)6325 void nft_obj_notify(struct net *net, const struct nft_table *table,
6326 		    struct nft_object *obj, u32 portid, u32 seq, int event,
6327 		    int family, int report, gfp_t gfp)
6328 {
6329 	struct sk_buff *skb;
6330 	int err;
6331 	char *buf = kasprintf(gfp, "%s:%u",
6332 			      table->name, net->nft.base_seq);
6333 
6334 	audit_log_nfcfg(buf,
6335 			family,
6336 			obj->handle,
6337 			event == NFT_MSG_NEWOBJ ?
6338 				 AUDIT_NFT_OP_OBJ_REGISTER :
6339 				 AUDIT_NFT_OP_OBJ_UNREGISTER,
6340 			gfp);
6341 	kfree(buf);
6342 
6343 	if (!report &&
6344 	    !nfnetlink_has_listeners(net, NFNLGRP_NFTABLES))
6345 		return;
6346 
6347 	skb = nlmsg_new(NLMSG_GOODSIZE, gfp);
6348 	if (skb == NULL)
6349 		goto err;
6350 
6351 	err = nf_tables_fill_obj_info(skb, net, portid, seq, event, 0, family,
6352 				      table, obj, false);
6353 	if (err < 0) {
6354 		kfree_skb(skb);
6355 		goto err;
6356 	}
6357 
6358 	nft_notify_enqueue(skb, report, &net->nft.notify_list);
6359 	return;
6360 err:
6361 	nfnetlink_set_err(net, portid, NFNLGRP_NFTABLES, -ENOBUFS);
6362 }
6363 EXPORT_SYMBOL_GPL(nft_obj_notify);
6364 
nf_tables_obj_notify(const struct nft_ctx * ctx,struct nft_object * obj,int event)6365 static void nf_tables_obj_notify(const struct nft_ctx *ctx,
6366 				 struct nft_object *obj, int event)
6367 {
6368 	nft_obj_notify(ctx->net, ctx->table, obj, ctx->portid, ctx->seq, event,
6369 		       ctx->family, ctx->report, GFP_KERNEL);
6370 }
6371 
6372 /*
6373  * Flow tables
6374  */
nft_register_flowtable_type(struct nf_flowtable_type * type)6375 void nft_register_flowtable_type(struct nf_flowtable_type *type)
6376 {
6377 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
6378 	list_add_tail_rcu(&type->list, &nf_tables_flowtables);
6379 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
6380 }
6381 EXPORT_SYMBOL_GPL(nft_register_flowtable_type);
6382 
nft_unregister_flowtable_type(struct nf_flowtable_type * type)6383 void nft_unregister_flowtable_type(struct nf_flowtable_type *type)
6384 {
6385 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
6386 	list_del_rcu(&type->list);
6387 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
6388 }
6389 EXPORT_SYMBOL_GPL(nft_unregister_flowtable_type);
6390 
6391 static const struct nla_policy nft_flowtable_policy[NFTA_FLOWTABLE_MAX + 1] = {
6392 	[NFTA_FLOWTABLE_TABLE]		= { .type = NLA_STRING,
6393 					    .len = NFT_NAME_MAXLEN - 1 },
6394 	[NFTA_FLOWTABLE_NAME]		= { .type = NLA_STRING,
6395 					    .len = NFT_NAME_MAXLEN - 1 },
6396 	[NFTA_FLOWTABLE_HOOK]		= { .type = NLA_NESTED },
6397 	[NFTA_FLOWTABLE_HANDLE]		= { .type = NLA_U64 },
6398 	[NFTA_FLOWTABLE_FLAGS]		= { .type = NLA_U32 },
6399 };
6400 
nft_flowtable_lookup(const struct nft_table * table,const struct nlattr * nla,u8 genmask)6401 struct nft_flowtable *nft_flowtable_lookup(const struct nft_table *table,
6402 					   const struct nlattr *nla, u8 genmask)
6403 {
6404 	struct nft_flowtable *flowtable;
6405 
6406 	list_for_each_entry_rcu(flowtable, &table->flowtables, list) {
6407 		if (!nla_strcmp(nla, flowtable->name) &&
6408 		    nft_active_genmask(flowtable, genmask))
6409 			return flowtable;
6410 	}
6411 	return ERR_PTR(-ENOENT);
6412 }
6413 EXPORT_SYMBOL_GPL(nft_flowtable_lookup);
6414 
nf_tables_deactivate_flowtable(const struct nft_ctx * ctx,struct nft_flowtable * flowtable,enum nft_trans_phase phase)6415 void nf_tables_deactivate_flowtable(const struct nft_ctx *ctx,
6416 				    struct nft_flowtable *flowtable,
6417 				    enum nft_trans_phase phase)
6418 {
6419 	switch (phase) {
6420 	case NFT_TRANS_PREPARE:
6421 	case NFT_TRANS_ABORT:
6422 	case NFT_TRANS_RELEASE:
6423 		flowtable->use--;
6424 		fallthrough;
6425 	default:
6426 		return;
6427 	}
6428 }
6429 EXPORT_SYMBOL_GPL(nf_tables_deactivate_flowtable);
6430 
6431 static struct nft_flowtable *
nft_flowtable_lookup_byhandle(const struct nft_table * table,const struct nlattr * nla,u8 genmask)6432 nft_flowtable_lookup_byhandle(const struct nft_table *table,
6433 			      const struct nlattr *nla, u8 genmask)
6434 {
6435        struct nft_flowtable *flowtable;
6436 
6437        list_for_each_entry(flowtable, &table->flowtables, list) {
6438                if (be64_to_cpu(nla_get_be64(nla)) == flowtable->handle &&
6439                    nft_active_genmask(flowtable, genmask))
6440                        return flowtable;
6441        }
6442        return ERR_PTR(-ENOENT);
6443 }
6444 
6445 struct nft_flowtable_hook {
6446 	u32			num;
6447 	int			priority;
6448 	struct list_head	list;
6449 };
6450 
6451 static const struct nla_policy nft_flowtable_hook_policy[NFTA_FLOWTABLE_HOOK_MAX + 1] = {
6452 	[NFTA_FLOWTABLE_HOOK_NUM]	= { .type = NLA_U32 },
6453 	[NFTA_FLOWTABLE_HOOK_PRIORITY]	= { .type = NLA_U32 },
6454 	[NFTA_FLOWTABLE_HOOK_DEVS]	= { .type = NLA_NESTED },
6455 };
6456 
nft_flowtable_parse_hook(const struct nft_ctx * ctx,const struct nlattr * attr,struct nft_flowtable_hook * flowtable_hook,struct nft_flowtable * flowtable,bool add)6457 static int nft_flowtable_parse_hook(const struct nft_ctx *ctx,
6458 				    const struct nlattr *attr,
6459 				    struct nft_flowtable_hook *flowtable_hook,
6460 				    struct nft_flowtable *flowtable, bool add)
6461 {
6462 	struct nlattr *tb[NFTA_FLOWTABLE_HOOK_MAX + 1];
6463 	struct nft_hook *hook;
6464 	int hooknum, priority;
6465 	int err;
6466 
6467 	INIT_LIST_HEAD(&flowtable_hook->list);
6468 
6469 	err = nla_parse_nested_deprecated(tb, NFTA_FLOWTABLE_HOOK_MAX, attr,
6470 					  nft_flowtable_hook_policy, NULL);
6471 	if (err < 0)
6472 		return err;
6473 
6474 	if (add) {
6475 		if (!tb[NFTA_FLOWTABLE_HOOK_NUM] ||
6476 		    !tb[NFTA_FLOWTABLE_HOOK_PRIORITY])
6477 			return -EINVAL;
6478 
6479 		hooknum = ntohl(nla_get_be32(tb[NFTA_FLOWTABLE_HOOK_NUM]));
6480 		if (hooknum != NF_NETDEV_INGRESS)
6481 			return -EOPNOTSUPP;
6482 
6483 		priority = ntohl(nla_get_be32(tb[NFTA_FLOWTABLE_HOOK_PRIORITY]));
6484 
6485 		flowtable_hook->priority	= priority;
6486 		flowtable_hook->num		= hooknum;
6487 	} else {
6488 		if (tb[NFTA_FLOWTABLE_HOOK_NUM]) {
6489 			hooknum = ntohl(nla_get_be32(tb[NFTA_FLOWTABLE_HOOK_NUM]));
6490 			if (hooknum != flowtable->hooknum)
6491 				return -EOPNOTSUPP;
6492 		}
6493 
6494 		if (tb[NFTA_FLOWTABLE_HOOK_PRIORITY]) {
6495 			priority = ntohl(nla_get_be32(tb[NFTA_FLOWTABLE_HOOK_PRIORITY]));
6496 			if (priority != flowtable->data.priority)
6497 				return -EOPNOTSUPP;
6498 		}
6499 
6500 		flowtable_hook->priority	= flowtable->data.priority;
6501 		flowtable_hook->num		= flowtable->hooknum;
6502 	}
6503 
6504 	if (tb[NFTA_FLOWTABLE_HOOK_DEVS]) {
6505 		err = nf_tables_parse_netdev_hooks(ctx->net,
6506 						   tb[NFTA_FLOWTABLE_HOOK_DEVS],
6507 						   &flowtable_hook->list);
6508 		if (err < 0)
6509 			return err;
6510 	}
6511 
6512 	list_for_each_entry(hook, &flowtable_hook->list, list) {
6513 		hook->ops.pf		= NFPROTO_NETDEV;
6514 		hook->ops.hooknum	= flowtable_hook->num;
6515 		hook->ops.priority	= flowtable_hook->priority;
6516 		hook->ops.priv		= &flowtable->data;
6517 		hook->ops.hook		= flowtable->data.type->hook;
6518 	}
6519 
6520 	return err;
6521 }
6522 
__nft_flowtable_type_get(u8 family)6523 static const struct nf_flowtable_type *__nft_flowtable_type_get(u8 family)
6524 {
6525 	const struct nf_flowtable_type *type;
6526 
6527 	list_for_each_entry(type, &nf_tables_flowtables, list) {
6528 		if (family == type->family)
6529 			return type;
6530 	}
6531 	return NULL;
6532 }
6533 
6534 static const struct nf_flowtable_type *
nft_flowtable_type_get(struct net * net,u8 family)6535 nft_flowtable_type_get(struct net *net, u8 family)
6536 {
6537 	const struct nf_flowtable_type *type;
6538 
6539 	type = __nft_flowtable_type_get(family);
6540 	if (type != NULL && try_module_get(type->owner))
6541 		return type;
6542 
6543 	lockdep_nfnl_nft_mutex_not_held();
6544 #ifdef CONFIG_MODULES
6545 	if (type == NULL) {
6546 		if (nft_request_module(net, "nf-flowtable-%u", family) == -EAGAIN)
6547 			return ERR_PTR(-EAGAIN);
6548 	}
6549 #endif
6550 	return ERR_PTR(-ENOENT);
6551 }
6552 
6553 /* Only called from error and netdev event paths. */
nft_unregister_flowtable_hook(struct net * net,struct nft_flowtable * flowtable,struct nft_hook * hook)6554 static void nft_unregister_flowtable_hook(struct net *net,
6555 					  struct nft_flowtable *flowtable,
6556 					  struct nft_hook *hook)
6557 {
6558 	nf_unregister_net_hook(net, &hook->ops);
6559 	flowtable->data.type->setup(&flowtable->data, hook->ops.dev,
6560 				    FLOW_BLOCK_UNBIND);
6561 }
6562 
nft_unregister_flowtable_net_hooks(struct net * net,struct list_head * hook_list)6563 static void nft_unregister_flowtable_net_hooks(struct net *net,
6564 					       struct list_head *hook_list)
6565 {
6566 	struct nft_hook *hook;
6567 
6568 	list_for_each_entry(hook, hook_list, list)
6569 		nf_unregister_net_hook(net, &hook->ops);
6570 }
6571 
nft_register_flowtable_net_hooks(struct net * net,struct nft_table * table,struct list_head * hook_list,struct nft_flowtable * flowtable)6572 static int nft_register_flowtable_net_hooks(struct net *net,
6573 					    struct nft_table *table,
6574 					    struct list_head *hook_list,
6575 					    struct nft_flowtable *flowtable)
6576 {
6577 	struct nft_hook *hook, *hook2, *next;
6578 	struct nft_flowtable *ft;
6579 	int err, i = 0;
6580 
6581 	list_for_each_entry(hook, hook_list, list) {
6582 		list_for_each_entry(ft, &table->flowtables, list) {
6583 			if (!nft_is_active_next(net, ft))
6584 				continue;
6585 
6586 			list_for_each_entry(hook2, &ft->hook_list, list) {
6587 				if (hook->ops.dev == hook2->ops.dev &&
6588 				    hook->ops.pf == hook2->ops.pf) {
6589 					err = -EEXIST;
6590 					goto err_unregister_net_hooks;
6591 				}
6592 			}
6593 		}
6594 
6595 		err = flowtable->data.type->setup(&flowtable->data,
6596 						  hook->ops.dev,
6597 						  FLOW_BLOCK_BIND);
6598 		if (err < 0)
6599 			goto err_unregister_net_hooks;
6600 
6601 		err = nf_register_net_hook(net, &hook->ops);
6602 		if (err < 0) {
6603 			flowtable->data.type->setup(&flowtable->data,
6604 						    hook->ops.dev,
6605 						    FLOW_BLOCK_UNBIND);
6606 			goto err_unregister_net_hooks;
6607 		}
6608 
6609 		i++;
6610 	}
6611 
6612 	return 0;
6613 
6614 err_unregister_net_hooks:
6615 	list_for_each_entry_safe(hook, next, hook_list, list) {
6616 		if (i-- <= 0)
6617 			break;
6618 
6619 		nft_unregister_flowtable_hook(net, flowtable, hook);
6620 		list_del_rcu(&hook->list);
6621 		kfree_rcu(hook, rcu);
6622 	}
6623 
6624 	return err;
6625 }
6626 
nft_flowtable_hooks_destroy(struct list_head * hook_list)6627 static void nft_flowtable_hooks_destroy(struct list_head *hook_list)
6628 {
6629 	struct nft_hook *hook, *next;
6630 
6631 	list_for_each_entry_safe(hook, next, hook_list, list) {
6632 		list_del_rcu(&hook->list);
6633 		kfree_rcu(hook, rcu);
6634 	}
6635 }
6636 
nft_flowtable_update(struct nft_ctx * ctx,const struct nlmsghdr * nlh,struct nft_flowtable * flowtable)6637 static int nft_flowtable_update(struct nft_ctx *ctx, const struct nlmsghdr *nlh,
6638 				struct nft_flowtable *flowtable)
6639 {
6640 	const struct nlattr * const *nla = ctx->nla;
6641 	struct nft_flowtable_hook flowtable_hook;
6642 	struct nft_hook *hook, *next;
6643 	struct nft_trans *trans;
6644 	bool unregister = false;
6645 	u32 flags;
6646 	int err;
6647 
6648 	err = nft_flowtable_parse_hook(ctx, nla[NFTA_FLOWTABLE_HOOK],
6649 				       &flowtable_hook, flowtable, false);
6650 	if (err < 0)
6651 		return err;
6652 
6653 	list_for_each_entry_safe(hook, next, &flowtable_hook.list, list) {
6654 		if (nft_hook_list_find(&flowtable->hook_list, hook)) {
6655 			list_del(&hook->list);
6656 			kfree(hook);
6657 		}
6658 	}
6659 
6660 	if (nla[NFTA_FLOWTABLE_FLAGS]) {
6661 		flags = ntohl(nla_get_be32(nla[NFTA_FLOWTABLE_FLAGS]));
6662 		if (flags & ~NFT_FLOWTABLE_MASK) {
6663 			err = -EOPNOTSUPP;
6664 			goto err_flowtable_update_hook;
6665 		}
6666 		if ((flowtable->data.flags & NFT_FLOWTABLE_HW_OFFLOAD) ^
6667 		    (flags & NFT_FLOWTABLE_HW_OFFLOAD)) {
6668 			err = -EOPNOTSUPP;
6669 			goto err_flowtable_update_hook;
6670 		}
6671 	} else {
6672 		flags = flowtable->data.flags;
6673 	}
6674 
6675 	err = nft_register_flowtable_net_hooks(ctx->net, ctx->table,
6676 					       &flowtable_hook.list, flowtable);
6677 	if (err < 0)
6678 		goto err_flowtable_update_hook;
6679 
6680 	trans = nft_trans_alloc(ctx, NFT_MSG_NEWFLOWTABLE,
6681 				sizeof(struct nft_trans_flowtable));
6682 	if (!trans) {
6683 		unregister = true;
6684 		err = -ENOMEM;
6685 		goto err_flowtable_update_hook;
6686 	}
6687 
6688 	nft_trans_flowtable_flags(trans) = flags;
6689 	nft_trans_flowtable(trans) = flowtable;
6690 	nft_trans_flowtable_update(trans) = true;
6691 	INIT_LIST_HEAD(&nft_trans_flowtable_hooks(trans));
6692 	list_splice(&flowtable_hook.list, &nft_trans_flowtable_hooks(trans));
6693 
6694 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
6695 
6696 	return 0;
6697 
6698 err_flowtable_update_hook:
6699 	list_for_each_entry_safe(hook, next, &flowtable_hook.list, list) {
6700 		if (unregister)
6701 			nft_unregister_flowtable_hook(ctx->net, flowtable, hook);
6702 		list_del_rcu(&hook->list);
6703 		kfree_rcu(hook, rcu);
6704 	}
6705 
6706 	return err;
6707 
6708 }
6709 
nf_tables_newflowtable(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)6710 static int nf_tables_newflowtable(struct net *net, struct sock *nlsk,
6711 				  struct sk_buff *skb,
6712 				  const struct nlmsghdr *nlh,
6713 				  const struct nlattr * const nla[],
6714 				  struct netlink_ext_ack *extack)
6715 {
6716 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
6717 	struct nft_flowtable_hook flowtable_hook;
6718 	const struct nf_flowtable_type *type;
6719 	u8 genmask = nft_genmask_next(net);
6720 	int family = nfmsg->nfgen_family;
6721 	struct nft_flowtable *flowtable;
6722 	struct nft_hook *hook, *next;
6723 	struct nft_table *table;
6724 	struct nft_ctx ctx;
6725 	int err;
6726 
6727 	if (!nla[NFTA_FLOWTABLE_TABLE] ||
6728 	    !nla[NFTA_FLOWTABLE_NAME] ||
6729 	    !nla[NFTA_FLOWTABLE_HOOK])
6730 		return -EINVAL;
6731 
6732 	table = nft_table_lookup(net, nla[NFTA_FLOWTABLE_TABLE], family,
6733 				 genmask);
6734 	if (IS_ERR(table)) {
6735 		NL_SET_BAD_ATTR(extack, nla[NFTA_FLOWTABLE_TABLE]);
6736 		return PTR_ERR(table);
6737 	}
6738 
6739 	flowtable = nft_flowtable_lookup(table, nla[NFTA_FLOWTABLE_NAME],
6740 					 genmask);
6741 	if (IS_ERR(flowtable)) {
6742 		err = PTR_ERR(flowtable);
6743 		if (err != -ENOENT) {
6744 			NL_SET_BAD_ATTR(extack, nla[NFTA_FLOWTABLE_NAME]);
6745 			return err;
6746 		}
6747 	} else {
6748 		if (nlh->nlmsg_flags & NLM_F_EXCL) {
6749 			NL_SET_BAD_ATTR(extack, nla[NFTA_FLOWTABLE_NAME]);
6750 			return -EEXIST;
6751 		}
6752 
6753 		nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
6754 
6755 		return nft_flowtable_update(&ctx, nlh, flowtable);
6756 	}
6757 
6758 	nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
6759 
6760 	flowtable = kzalloc(sizeof(*flowtable), GFP_KERNEL);
6761 	if (!flowtable)
6762 		return -ENOMEM;
6763 
6764 	flowtable->table = table;
6765 	flowtable->handle = nf_tables_alloc_handle(table);
6766 	INIT_LIST_HEAD(&flowtable->hook_list);
6767 
6768 	flowtable->name = nla_strdup(nla[NFTA_FLOWTABLE_NAME], GFP_KERNEL);
6769 	if (!flowtable->name) {
6770 		err = -ENOMEM;
6771 		goto err1;
6772 	}
6773 
6774 	type = nft_flowtable_type_get(net, family);
6775 	if (IS_ERR(type)) {
6776 		err = PTR_ERR(type);
6777 		goto err2;
6778 	}
6779 
6780 	if (nla[NFTA_FLOWTABLE_FLAGS]) {
6781 		flowtable->data.flags =
6782 			ntohl(nla_get_be32(nla[NFTA_FLOWTABLE_FLAGS]));
6783 		if (flowtable->data.flags & ~NFT_FLOWTABLE_MASK) {
6784 			err = -EOPNOTSUPP;
6785 			goto err3;
6786 		}
6787 	}
6788 
6789 	write_pnet(&flowtable->data.net, net);
6790 	flowtable->data.type = type;
6791 	err = type->init(&flowtable->data);
6792 	if (err < 0)
6793 		goto err3;
6794 
6795 	err = nft_flowtable_parse_hook(&ctx, nla[NFTA_FLOWTABLE_HOOK],
6796 				       &flowtable_hook, flowtable, true);
6797 	if (err < 0)
6798 		goto err4;
6799 
6800 	list_splice(&flowtable_hook.list, &flowtable->hook_list);
6801 	flowtable->data.priority = flowtable_hook.priority;
6802 	flowtable->hooknum = flowtable_hook.num;
6803 
6804 	err = nft_register_flowtable_net_hooks(ctx.net, table,
6805 					       &flowtable->hook_list,
6806 					       flowtable);
6807 	if (err < 0) {
6808 		nft_flowtable_hooks_destroy(&flowtable->hook_list);
6809 		goto err4;
6810 	}
6811 
6812 	err = nft_trans_flowtable_add(&ctx, NFT_MSG_NEWFLOWTABLE, flowtable);
6813 	if (err < 0)
6814 		goto err5;
6815 
6816 	list_add_tail_rcu(&flowtable->list, &table->flowtables);
6817 	table->use++;
6818 
6819 	return 0;
6820 err5:
6821 	list_for_each_entry_safe(hook, next, &flowtable->hook_list, list) {
6822 		nft_unregister_flowtable_hook(net, flowtable, hook);
6823 		list_del_rcu(&hook->list);
6824 		kfree_rcu(hook, rcu);
6825 	}
6826 err4:
6827 	flowtable->data.type->free(&flowtable->data);
6828 err3:
6829 	module_put(type->owner);
6830 err2:
6831 	kfree(flowtable->name);
6832 err1:
6833 	kfree(flowtable);
6834 	return err;
6835 }
6836 
nft_flowtable_hook_release(struct nft_flowtable_hook * flowtable_hook)6837 static void nft_flowtable_hook_release(struct nft_flowtable_hook *flowtable_hook)
6838 {
6839 	struct nft_hook *this, *next;
6840 
6841 	list_for_each_entry_safe(this, next, &flowtable_hook->list, list) {
6842 		list_del(&this->list);
6843 		kfree(this);
6844 	}
6845 }
6846 
nft_delflowtable_hook(struct nft_ctx * ctx,struct nft_flowtable * flowtable)6847 static int nft_delflowtable_hook(struct nft_ctx *ctx,
6848 				 struct nft_flowtable *flowtable)
6849 {
6850 	const struct nlattr * const *nla = ctx->nla;
6851 	struct nft_flowtable_hook flowtable_hook;
6852 	LIST_HEAD(flowtable_del_list);
6853 	struct nft_hook *this, *hook;
6854 	struct nft_trans *trans;
6855 	int err;
6856 
6857 	err = nft_flowtable_parse_hook(ctx, nla[NFTA_FLOWTABLE_HOOK],
6858 				       &flowtable_hook, flowtable, false);
6859 	if (err < 0)
6860 		return err;
6861 
6862 	list_for_each_entry(this, &flowtable_hook.list, list) {
6863 		hook = nft_hook_list_find(&flowtable->hook_list, this);
6864 		if (!hook) {
6865 			err = -ENOENT;
6866 			goto err_flowtable_del_hook;
6867 		}
6868 		list_move(&hook->list, &flowtable_del_list);
6869 	}
6870 
6871 	trans = nft_trans_alloc(ctx, NFT_MSG_DELFLOWTABLE,
6872 				sizeof(struct nft_trans_flowtable));
6873 	if (!trans) {
6874 		err = -ENOMEM;
6875 		goto err_flowtable_del_hook;
6876 	}
6877 
6878 	nft_trans_flowtable(trans) = flowtable;
6879 	nft_trans_flowtable_update(trans) = true;
6880 	INIT_LIST_HEAD(&nft_trans_flowtable_hooks(trans));
6881 	list_splice(&flowtable_del_list, &nft_trans_flowtable_hooks(trans));
6882 	nft_flowtable_hook_release(&flowtable_hook);
6883 
6884 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
6885 
6886 	return 0;
6887 
6888 err_flowtable_del_hook:
6889 	list_splice(&flowtable_del_list, &flowtable->hook_list);
6890 	nft_flowtable_hook_release(&flowtable_hook);
6891 
6892 	return err;
6893 }
6894 
nf_tables_delflowtable(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)6895 static int nf_tables_delflowtable(struct net *net, struct sock *nlsk,
6896 				  struct sk_buff *skb,
6897 				  const struct nlmsghdr *nlh,
6898 				  const struct nlattr * const nla[],
6899 				  struct netlink_ext_ack *extack)
6900 {
6901 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
6902 	u8 genmask = nft_genmask_next(net);
6903 	int family = nfmsg->nfgen_family;
6904 	struct nft_flowtable *flowtable;
6905 	const struct nlattr *attr;
6906 	struct nft_table *table;
6907 	struct nft_ctx ctx;
6908 
6909 	if (!nla[NFTA_FLOWTABLE_TABLE] ||
6910 	    (!nla[NFTA_FLOWTABLE_NAME] &&
6911 	     !nla[NFTA_FLOWTABLE_HANDLE]))
6912 		return -EINVAL;
6913 
6914 	table = nft_table_lookup(net, nla[NFTA_FLOWTABLE_TABLE], family,
6915 				 genmask);
6916 	if (IS_ERR(table)) {
6917 		NL_SET_BAD_ATTR(extack, nla[NFTA_FLOWTABLE_TABLE]);
6918 		return PTR_ERR(table);
6919 	}
6920 
6921 	if (nla[NFTA_FLOWTABLE_HANDLE]) {
6922 		attr = nla[NFTA_FLOWTABLE_HANDLE];
6923 		flowtable = nft_flowtable_lookup_byhandle(table, attr, genmask);
6924 	} else {
6925 		attr = nla[NFTA_FLOWTABLE_NAME];
6926 		flowtable = nft_flowtable_lookup(table, attr, genmask);
6927 	}
6928 
6929 	if (IS_ERR(flowtable)) {
6930 		NL_SET_BAD_ATTR(extack, attr);
6931 		return PTR_ERR(flowtable);
6932 	}
6933 
6934 	nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
6935 
6936 	if (nla[NFTA_FLOWTABLE_HOOK])
6937 		return nft_delflowtable_hook(&ctx, flowtable);
6938 
6939 	if (flowtable->use > 0) {
6940 		NL_SET_BAD_ATTR(extack, attr);
6941 		return -EBUSY;
6942 	}
6943 
6944 	return nft_delflowtable(&ctx, flowtable);
6945 }
6946 
nf_tables_fill_flowtable_info(struct sk_buff * skb,struct net * net,u32 portid,u32 seq,int event,u32 flags,int family,struct nft_flowtable * flowtable,struct list_head * hook_list)6947 static int nf_tables_fill_flowtable_info(struct sk_buff *skb, struct net *net,
6948 					 u32 portid, u32 seq, int event,
6949 					 u32 flags, int family,
6950 					 struct nft_flowtable *flowtable,
6951 					 struct list_head *hook_list)
6952 {
6953 	struct nlattr *nest, *nest_devs;
6954 	struct nft_hook *hook;
6955 	struct nlmsghdr *nlh;
6956 
6957 	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
6958 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, family,
6959 			   NFNETLINK_V0, nft_base_seq(net));
6960 	if (!nlh)
6961 		goto nla_put_failure;
6962 
6963 	if (nla_put_string(skb, NFTA_FLOWTABLE_TABLE, flowtable->table->name) ||
6964 	    nla_put_string(skb, NFTA_FLOWTABLE_NAME, flowtable->name) ||
6965 	    nla_put_be32(skb, NFTA_FLOWTABLE_USE, htonl(flowtable->use)) ||
6966 	    nla_put_be64(skb, NFTA_FLOWTABLE_HANDLE, cpu_to_be64(flowtable->handle),
6967 			 NFTA_FLOWTABLE_PAD) ||
6968 	    nla_put_be32(skb, NFTA_FLOWTABLE_FLAGS, htonl(flowtable->data.flags)))
6969 		goto nla_put_failure;
6970 
6971 	nest = nla_nest_start_noflag(skb, NFTA_FLOWTABLE_HOOK);
6972 	if (!nest)
6973 		goto nla_put_failure;
6974 	if (nla_put_be32(skb, NFTA_FLOWTABLE_HOOK_NUM, htonl(flowtable->hooknum)) ||
6975 	    nla_put_be32(skb, NFTA_FLOWTABLE_HOOK_PRIORITY, htonl(flowtable->data.priority)))
6976 		goto nla_put_failure;
6977 
6978 	nest_devs = nla_nest_start_noflag(skb, NFTA_FLOWTABLE_HOOK_DEVS);
6979 	if (!nest_devs)
6980 		goto nla_put_failure;
6981 
6982 	list_for_each_entry_rcu(hook, hook_list, list) {
6983 		if (nla_put_string(skb, NFTA_DEVICE_NAME, hook->ops.dev->name))
6984 			goto nla_put_failure;
6985 	}
6986 	nla_nest_end(skb, nest_devs);
6987 	nla_nest_end(skb, nest);
6988 
6989 	nlmsg_end(skb, nlh);
6990 	return 0;
6991 
6992 nla_put_failure:
6993 	nlmsg_trim(skb, nlh);
6994 	return -1;
6995 }
6996 
6997 struct nft_flowtable_filter {
6998 	char		*table;
6999 };
7000 
nf_tables_dump_flowtable(struct sk_buff * skb,struct netlink_callback * cb)7001 static int nf_tables_dump_flowtable(struct sk_buff *skb,
7002 				    struct netlink_callback *cb)
7003 {
7004 	const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
7005 	struct nft_flowtable_filter *filter = cb->data;
7006 	unsigned int idx = 0, s_idx = cb->args[0];
7007 	struct net *net = sock_net(skb->sk);
7008 	int family = nfmsg->nfgen_family;
7009 	struct nft_flowtable *flowtable;
7010 	const struct nft_table *table;
7011 
7012 	rcu_read_lock();
7013 	cb->seq = net->nft.base_seq;
7014 
7015 	list_for_each_entry_rcu(table, &net->nft.tables, list) {
7016 		if (family != NFPROTO_UNSPEC && family != table->family)
7017 			continue;
7018 
7019 		list_for_each_entry_rcu(flowtable, &table->flowtables, list) {
7020 			if (!nft_is_active(net, flowtable))
7021 				goto cont;
7022 			if (idx < s_idx)
7023 				goto cont;
7024 			if (idx > s_idx)
7025 				memset(&cb->args[1], 0,
7026 				       sizeof(cb->args) - sizeof(cb->args[0]));
7027 			if (filter && filter->table &&
7028 			    strcmp(filter->table, table->name))
7029 				goto cont;
7030 
7031 			if (nf_tables_fill_flowtable_info(skb, net, NETLINK_CB(cb->skb).portid,
7032 							  cb->nlh->nlmsg_seq,
7033 							  NFT_MSG_NEWFLOWTABLE,
7034 							  NLM_F_MULTI | NLM_F_APPEND,
7035 							  table->family,
7036 							  flowtable,
7037 							  &flowtable->hook_list) < 0)
7038 				goto done;
7039 
7040 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
7041 cont:
7042 			idx++;
7043 		}
7044 	}
7045 done:
7046 	rcu_read_unlock();
7047 
7048 	cb->args[0] = idx;
7049 	return skb->len;
7050 }
7051 
nf_tables_dump_flowtable_start(struct netlink_callback * cb)7052 static int nf_tables_dump_flowtable_start(struct netlink_callback *cb)
7053 {
7054 	const struct nlattr * const *nla = cb->data;
7055 	struct nft_flowtable_filter *filter = NULL;
7056 
7057 	if (nla[NFTA_FLOWTABLE_TABLE]) {
7058 		filter = kzalloc(sizeof(*filter), GFP_ATOMIC);
7059 		if (!filter)
7060 			return -ENOMEM;
7061 
7062 		filter->table = nla_strdup(nla[NFTA_FLOWTABLE_TABLE],
7063 					   GFP_ATOMIC);
7064 		if (!filter->table) {
7065 			kfree(filter);
7066 			return -ENOMEM;
7067 		}
7068 	}
7069 
7070 	cb->data = filter;
7071 	return 0;
7072 }
7073 
nf_tables_dump_flowtable_done(struct netlink_callback * cb)7074 static int nf_tables_dump_flowtable_done(struct netlink_callback *cb)
7075 {
7076 	struct nft_flowtable_filter *filter = cb->data;
7077 
7078 	if (!filter)
7079 		return 0;
7080 
7081 	kfree(filter->table);
7082 	kfree(filter);
7083 
7084 	return 0;
7085 }
7086 
7087 /* called with rcu_read_lock held */
nf_tables_getflowtable(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)7088 static int nf_tables_getflowtable(struct net *net, struct sock *nlsk,
7089 				  struct sk_buff *skb,
7090 				  const struct nlmsghdr *nlh,
7091 				  const struct nlattr * const nla[],
7092 				  struct netlink_ext_ack *extack)
7093 {
7094 	const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
7095 	u8 genmask = nft_genmask_cur(net);
7096 	int family = nfmsg->nfgen_family;
7097 	struct nft_flowtable *flowtable;
7098 	const struct nft_table *table;
7099 	struct sk_buff *skb2;
7100 	int err;
7101 
7102 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
7103 		struct netlink_dump_control c = {
7104 			.start = nf_tables_dump_flowtable_start,
7105 			.dump = nf_tables_dump_flowtable,
7106 			.done = nf_tables_dump_flowtable_done,
7107 			.module = THIS_MODULE,
7108 			.data = (void *)nla,
7109 		};
7110 
7111 		return nft_netlink_dump_start_rcu(nlsk, skb, nlh, &c);
7112 	}
7113 
7114 	if (!nla[NFTA_FLOWTABLE_NAME])
7115 		return -EINVAL;
7116 
7117 	table = nft_table_lookup(net, nla[NFTA_FLOWTABLE_TABLE], family,
7118 				 genmask);
7119 	if (IS_ERR(table))
7120 		return PTR_ERR(table);
7121 
7122 	flowtable = nft_flowtable_lookup(table, nla[NFTA_FLOWTABLE_NAME],
7123 					 genmask);
7124 	if (IS_ERR(flowtable))
7125 		return PTR_ERR(flowtable);
7126 
7127 	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
7128 	if (!skb2)
7129 		return -ENOMEM;
7130 
7131 	err = nf_tables_fill_flowtable_info(skb2, net, NETLINK_CB(skb).portid,
7132 					    nlh->nlmsg_seq,
7133 					    NFT_MSG_NEWFLOWTABLE, 0, family,
7134 					    flowtable, &flowtable->hook_list);
7135 	if (err < 0)
7136 		goto err_fill_flowtable_info;
7137 
7138 	return nfnetlink_unicast(skb2, net, NETLINK_CB(skb).portid);
7139 
7140 err_fill_flowtable_info:
7141 	kfree_skb(skb2);
7142 	return err;
7143 }
7144 
nf_tables_flowtable_notify(struct nft_ctx * ctx,struct nft_flowtable * flowtable,struct list_head * hook_list,int event)7145 static void nf_tables_flowtable_notify(struct nft_ctx *ctx,
7146 				       struct nft_flowtable *flowtable,
7147 				       struct list_head *hook_list,
7148 				       int event)
7149 {
7150 	struct sk_buff *skb;
7151 	int err;
7152 
7153 	if (!ctx->report &&
7154 	    !nfnetlink_has_listeners(ctx->net, NFNLGRP_NFTABLES))
7155 		return;
7156 
7157 	skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
7158 	if (skb == NULL)
7159 		goto err;
7160 
7161 	err = nf_tables_fill_flowtable_info(skb, ctx->net, ctx->portid,
7162 					    ctx->seq, event, 0,
7163 					    ctx->family, flowtable, hook_list);
7164 	if (err < 0) {
7165 		kfree_skb(skb);
7166 		goto err;
7167 	}
7168 
7169 	nft_notify_enqueue(skb, ctx->report, &ctx->net->nft.notify_list);
7170 	return;
7171 err:
7172 	nfnetlink_set_err(ctx->net, ctx->portid, NFNLGRP_NFTABLES, -ENOBUFS);
7173 }
7174 
nf_tables_flowtable_destroy(struct nft_flowtable * flowtable)7175 static void nf_tables_flowtable_destroy(struct nft_flowtable *flowtable)
7176 {
7177 	struct nft_hook *hook, *next;
7178 
7179 	flowtable->data.type->free(&flowtable->data);
7180 	list_for_each_entry_safe(hook, next, &flowtable->hook_list, list) {
7181 		flowtable->data.type->setup(&flowtable->data, hook->ops.dev,
7182 					    FLOW_BLOCK_UNBIND);
7183 		list_del_rcu(&hook->list);
7184 		kfree(hook);
7185 	}
7186 	kfree(flowtable->name);
7187 	module_put(flowtable->data.type->owner);
7188 	kfree(flowtable);
7189 }
7190 
nf_tables_fill_gen_info(struct sk_buff * skb,struct net * net,u32 portid,u32 seq)7191 static int nf_tables_fill_gen_info(struct sk_buff *skb, struct net *net,
7192 				   u32 portid, u32 seq)
7193 {
7194 	struct nlmsghdr *nlh;
7195 	char buf[TASK_COMM_LEN];
7196 	int event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWGEN);
7197 
7198 	nlh = nfnl_msg_put(skb, portid, seq, event, 0, AF_UNSPEC,
7199 			   NFNETLINK_V0, nft_base_seq(net));
7200 	if (!nlh)
7201 		goto nla_put_failure;
7202 
7203 	if (nla_put_be32(skb, NFTA_GEN_ID, htonl(net->nft.base_seq)) ||
7204 	    nla_put_be32(skb, NFTA_GEN_PROC_PID, htonl(task_pid_nr(current))) ||
7205 	    nla_put_string(skb, NFTA_GEN_PROC_NAME, get_task_comm(buf, current)))
7206 		goto nla_put_failure;
7207 
7208 	nlmsg_end(skb, nlh);
7209 	return 0;
7210 
7211 nla_put_failure:
7212 	nlmsg_trim(skb, nlh);
7213 	return -EMSGSIZE;
7214 }
7215 
nft_flowtable_event(unsigned long event,struct net_device * dev,struct nft_flowtable * flowtable)7216 static void nft_flowtable_event(unsigned long event, struct net_device *dev,
7217 				struct nft_flowtable *flowtable)
7218 {
7219 	struct nft_hook *hook;
7220 
7221 	list_for_each_entry(hook, &flowtable->hook_list, list) {
7222 		if (hook->ops.dev != dev)
7223 			continue;
7224 
7225 		/* flow_offload_netdev_event() cleans up entries for us. */
7226 		nft_unregister_flowtable_hook(dev_net(dev), flowtable, hook);
7227 		list_del_rcu(&hook->list);
7228 		kfree_rcu(hook, rcu);
7229 		break;
7230 	}
7231 }
7232 
nf_tables_flowtable_event(struct notifier_block * this,unsigned long event,void * ptr)7233 static int nf_tables_flowtable_event(struct notifier_block *this,
7234 				     unsigned long event, void *ptr)
7235 {
7236 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
7237 	struct nft_flowtable *flowtable;
7238 	struct nft_table *table;
7239 	struct net *net;
7240 
7241 	if (event != NETDEV_UNREGISTER)
7242 		return 0;
7243 
7244 	net = dev_net(dev);
7245 	mutex_lock(&net->nft.commit_mutex);
7246 	list_for_each_entry(table, &net->nft.tables, list) {
7247 		list_for_each_entry(flowtable, &table->flowtables, list) {
7248 			nft_flowtable_event(event, dev, flowtable);
7249 		}
7250 	}
7251 	mutex_unlock(&net->nft.commit_mutex);
7252 
7253 	return NOTIFY_DONE;
7254 }
7255 
7256 static struct notifier_block nf_tables_flowtable_notifier = {
7257 	.notifier_call	= nf_tables_flowtable_event,
7258 };
7259 
nf_tables_gen_notify(struct net * net,struct sk_buff * skb,int event)7260 static void nf_tables_gen_notify(struct net *net, struct sk_buff *skb,
7261 				 int event)
7262 {
7263 	struct nlmsghdr *nlh = nlmsg_hdr(skb);
7264 	struct sk_buff *skb2;
7265 	int err;
7266 
7267 	if (!nlmsg_report(nlh) &&
7268 	    !nfnetlink_has_listeners(net, NFNLGRP_NFTABLES))
7269 		return;
7270 
7271 	skb2 = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
7272 	if (skb2 == NULL)
7273 		goto err;
7274 
7275 	err = nf_tables_fill_gen_info(skb2, net, NETLINK_CB(skb).portid,
7276 				      nlh->nlmsg_seq);
7277 	if (err < 0) {
7278 		kfree_skb(skb2);
7279 		goto err;
7280 	}
7281 
7282 	nfnetlink_send(skb2, net, NETLINK_CB(skb).portid, NFNLGRP_NFTABLES,
7283 		       nlmsg_report(nlh), GFP_KERNEL);
7284 	return;
7285 err:
7286 	nfnetlink_set_err(net, NETLINK_CB(skb).portid, NFNLGRP_NFTABLES,
7287 			  -ENOBUFS);
7288 }
7289 
nf_tables_getgen(struct net * net,struct sock * nlsk,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const nla[],struct netlink_ext_ack * extack)7290 static int nf_tables_getgen(struct net *net, struct sock *nlsk,
7291 			    struct sk_buff *skb, const struct nlmsghdr *nlh,
7292 			    const struct nlattr * const nla[],
7293 			    struct netlink_ext_ack *extack)
7294 {
7295 	struct sk_buff *skb2;
7296 	int err;
7297 
7298 	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
7299 	if (skb2 == NULL)
7300 		return -ENOMEM;
7301 
7302 	err = nf_tables_fill_gen_info(skb2, net, NETLINK_CB(skb).portid,
7303 				      nlh->nlmsg_seq);
7304 	if (err < 0)
7305 		goto err_fill_gen_info;
7306 
7307 	return nfnetlink_unicast(skb2, net, NETLINK_CB(skb).portid);
7308 
7309 err_fill_gen_info:
7310 	kfree_skb(skb2);
7311 	return err;
7312 }
7313 
7314 static const struct nfnl_callback nf_tables_cb[NFT_MSG_MAX] = {
7315 	[NFT_MSG_NEWTABLE] = {
7316 		.call_batch	= nf_tables_newtable,
7317 		.attr_count	= NFTA_TABLE_MAX,
7318 		.policy		= nft_table_policy,
7319 	},
7320 	[NFT_MSG_GETTABLE] = {
7321 		.call_rcu	= nf_tables_gettable,
7322 		.attr_count	= NFTA_TABLE_MAX,
7323 		.policy		= nft_table_policy,
7324 	},
7325 	[NFT_MSG_DELTABLE] = {
7326 		.call_batch	= nf_tables_deltable,
7327 		.attr_count	= NFTA_TABLE_MAX,
7328 		.policy		= nft_table_policy,
7329 	},
7330 	[NFT_MSG_NEWCHAIN] = {
7331 		.call_batch	= nf_tables_newchain,
7332 		.attr_count	= NFTA_CHAIN_MAX,
7333 		.policy		= nft_chain_policy,
7334 	},
7335 	[NFT_MSG_GETCHAIN] = {
7336 		.call_rcu	= nf_tables_getchain,
7337 		.attr_count	= NFTA_CHAIN_MAX,
7338 		.policy		= nft_chain_policy,
7339 	},
7340 	[NFT_MSG_DELCHAIN] = {
7341 		.call_batch	= nf_tables_delchain,
7342 		.attr_count	= NFTA_CHAIN_MAX,
7343 		.policy		= nft_chain_policy,
7344 	},
7345 	[NFT_MSG_NEWRULE] = {
7346 		.call_batch	= nf_tables_newrule,
7347 		.attr_count	= NFTA_RULE_MAX,
7348 		.policy		= nft_rule_policy,
7349 	},
7350 	[NFT_MSG_GETRULE] = {
7351 		.call_rcu	= nf_tables_getrule,
7352 		.attr_count	= NFTA_RULE_MAX,
7353 		.policy		= nft_rule_policy,
7354 	},
7355 	[NFT_MSG_DELRULE] = {
7356 		.call_batch	= nf_tables_delrule,
7357 		.attr_count	= NFTA_RULE_MAX,
7358 		.policy		= nft_rule_policy,
7359 	},
7360 	[NFT_MSG_NEWSET] = {
7361 		.call_batch	= nf_tables_newset,
7362 		.attr_count	= NFTA_SET_MAX,
7363 		.policy		= nft_set_policy,
7364 	},
7365 	[NFT_MSG_GETSET] = {
7366 		.call_rcu	= nf_tables_getset,
7367 		.attr_count	= NFTA_SET_MAX,
7368 		.policy		= nft_set_policy,
7369 	},
7370 	[NFT_MSG_DELSET] = {
7371 		.call_batch	= nf_tables_delset,
7372 		.attr_count	= NFTA_SET_MAX,
7373 		.policy		= nft_set_policy,
7374 	},
7375 	[NFT_MSG_NEWSETELEM] = {
7376 		.call_batch	= nf_tables_newsetelem,
7377 		.attr_count	= NFTA_SET_ELEM_LIST_MAX,
7378 		.policy		= nft_set_elem_list_policy,
7379 	},
7380 	[NFT_MSG_GETSETELEM] = {
7381 		.call_rcu	= nf_tables_getsetelem,
7382 		.attr_count	= NFTA_SET_ELEM_LIST_MAX,
7383 		.policy		= nft_set_elem_list_policy,
7384 	},
7385 	[NFT_MSG_DELSETELEM] = {
7386 		.call_batch	= nf_tables_delsetelem,
7387 		.attr_count	= NFTA_SET_ELEM_LIST_MAX,
7388 		.policy		= nft_set_elem_list_policy,
7389 	},
7390 	[NFT_MSG_GETGEN] = {
7391 		.call_rcu	= nf_tables_getgen,
7392 	},
7393 	[NFT_MSG_NEWOBJ] = {
7394 		.call_batch	= nf_tables_newobj,
7395 		.attr_count	= NFTA_OBJ_MAX,
7396 		.policy		= nft_obj_policy,
7397 	},
7398 	[NFT_MSG_GETOBJ] = {
7399 		.call_rcu	= nf_tables_getobj,
7400 		.attr_count	= NFTA_OBJ_MAX,
7401 		.policy		= nft_obj_policy,
7402 	},
7403 	[NFT_MSG_DELOBJ] = {
7404 		.call_batch	= nf_tables_delobj,
7405 		.attr_count	= NFTA_OBJ_MAX,
7406 		.policy		= nft_obj_policy,
7407 	},
7408 	[NFT_MSG_GETOBJ_RESET] = {
7409 		.call_rcu	= nf_tables_getobj,
7410 		.attr_count	= NFTA_OBJ_MAX,
7411 		.policy		= nft_obj_policy,
7412 	},
7413 	[NFT_MSG_NEWFLOWTABLE] = {
7414 		.call_batch	= nf_tables_newflowtable,
7415 		.attr_count	= NFTA_FLOWTABLE_MAX,
7416 		.policy		= nft_flowtable_policy,
7417 	},
7418 	[NFT_MSG_GETFLOWTABLE] = {
7419 		.call_rcu	= nf_tables_getflowtable,
7420 		.attr_count	= NFTA_FLOWTABLE_MAX,
7421 		.policy		= nft_flowtable_policy,
7422 	},
7423 	[NFT_MSG_DELFLOWTABLE] = {
7424 		.call_batch	= nf_tables_delflowtable,
7425 		.attr_count	= NFTA_FLOWTABLE_MAX,
7426 		.policy		= nft_flowtable_policy,
7427 	},
7428 };
7429 
nf_tables_validate(struct net * net)7430 static int nf_tables_validate(struct net *net)
7431 {
7432 	struct nft_table *table;
7433 
7434 	switch (net->nft.validate_state) {
7435 	case NFT_VALIDATE_SKIP:
7436 		break;
7437 	case NFT_VALIDATE_NEED:
7438 		nft_validate_state_update(net, NFT_VALIDATE_DO);
7439 		fallthrough;
7440 	case NFT_VALIDATE_DO:
7441 		list_for_each_entry(table, &net->nft.tables, list) {
7442 			if (nft_table_validate(net, table) < 0)
7443 				return -EAGAIN;
7444 		}
7445 		break;
7446 	}
7447 
7448 	return 0;
7449 }
7450 
7451 /* a drop policy has to be deferred until all rules have been activated,
7452  * otherwise a large ruleset that contains a drop-policy base chain will
7453  * cause all packets to get dropped until the full transaction has been
7454  * processed.
7455  *
7456  * We defer the drop policy until the transaction has been finalized.
7457  */
nft_chain_commit_drop_policy(struct nft_trans * trans)7458 static void nft_chain_commit_drop_policy(struct nft_trans *trans)
7459 {
7460 	struct nft_base_chain *basechain;
7461 
7462 	if (nft_trans_chain_policy(trans) != NF_DROP)
7463 		return;
7464 
7465 	if (!nft_is_base_chain(trans->ctx.chain))
7466 		return;
7467 
7468 	basechain = nft_base_chain(trans->ctx.chain);
7469 	basechain->policy = NF_DROP;
7470 }
7471 
nft_chain_commit_update(struct nft_trans * trans)7472 static void nft_chain_commit_update(struct nft_trans *trans)
7473 {
7474 	struct nft_base_chain *basechain;
7475 
7476 	if (nft_trans_chain_name(trans)) {
7477 		rhltable_remove(&trans->ctx.table->chains_ht,
7478 				&trans->ctx.chain->rhlhead,
7479 				nft_chain_ht_params);
7480 		swap(trans->ctx.chain->name, nft_trans_chain_name(trans));
7481 		rhltable_insert_key(&trans->ctx.table->chains_ht,
7482 				    trans->ctx.chain->name,
7483 				    &trans->ctx.chain->rhlhead,
7484 				    nft_chain_ht_params);
7485 	}
7486 
7487 	if (!nft_is_base_chain(trans->ctx.chain))
7488 		return;
7489 
7490 	nft_chain_stats_replace(trans);
7491 
7492 	basechain = nft_base_chain(trans->ctx.chain);
7493 
7494 	switch (nft_trans_chain_policy(trans)) {
7495 	case NF_DROP:
7496 	case NF_ACCEPT:
7497 		basechain->policy = nft_trans_chain_policy(trans);
7498 		break;
7499 	}
7500 }
7501 
nft_obj_commit_update(struct nft_trans * trans)7502 static void nft_obj_commit_update(struct nft_trans *trans)
7503 {
7504 	struct nft_object *newobj;
7505 	struct nft_object *obj;
7506 
7507 	obj = nft_trans_obj(trans);
7508 	newobj = nft_trans_obj_newobj(trans);
7509 
7510 	if (obj->ops->update)
7511 		obj->ops->update(obj, newobj);
7512 
7513 	nft_obj_destroy(&trans->ctx, newobj);
7514 }
7515 
nft_commit_release(struct nft_trans * trans)7516 static void nft_commit_release(struct nft_trans *trans)
7517 {
7518 	switch (trans->msg_type) {
7519 	case NFT_MSG_DELTABLE:
7520 		nf_tables_table_destroy(&trans->ctx);
7521 		break;
7522 	case NFT_MSG_NEWCHAIN:
7523 		free_percpu(nft_trans_chain_stats(trans));
7524 		kfree(nft_trans_chain_name(trans));
7525 		break;
7526 	case NFT_MSG_DELCHAIN:
7527 		nf_tables_chain_destroy(&trans->ctx);
7528 		break;
7529 	case NFT_MSG_DELRULE:
7530 		nf_tables_rule_destroy(&trans->ctx, nft_trans_rule(trans));
7531 		break;
7532 	case NFT_MSG_DELSET:
7533 		nft_set_destroy(&trans->ctx, nft_trans_set(trans));
7534 		break;
7535 	case NFT_MSG_DELSETELEM:
7536 		nf_tables_set_elem_destroy(&trans->ctx,
7537 					   nft_trans_elem_set(trans),
7538 					   nft_trans_elem(trans).priv);
7539 		break;
7540 	case NFT_MSG_DELOBJ:
7541 		nft_obj_destroy(&trans->ctx, nft_trans_obj(trans));
7542 		break;
7543 	case NFT_MSG_DELFLOWTABLE:
7544 		if (nft_trans_flowtable_update(trans))
7545 			nft_flowtable_hooks_destroy(&nft_trans_flowtable_hooks(trans));
7546 		else
7547 			nf_tables_flowtable_destroy(nft_trans_flowtable(trans));
7548 		break;
7549 	}
7550 
7551 	if (trans->put_net)
7552 		put_net(trans->ctx.net);
7553 
7554 	kfree(trans);
7555 }
7556 
nf_tables_trans_destroy_work(struct work_struct * w)7557 static void nf_tables_trans_destroy_work(struct work_struct *w)
7558 {
7559 	struct nft_trans *trans, *next;
7560 	LIST_HEAD(head);
7561 
7562 	spin_lock(&nf_tables_destroy_list_lock);
7563 	list_splice_init(&nf_tables_destroy_list, &head);
7564 	spin_unlock(&nf_tables_destroy_list_lock);
7565 
7566 	if (list_empty(&head))
7567 		return;
7568 
7569 	synchronize_rcu();
7570 
7571 	list_for_each_entry_safe(trans, next, &head, list) {
7572 		list_del(&trans->list);
7573 		nft_commit_release(trans);
7574 	}
7575 }
7576 
nf_tables_trans_destroy_flush_work(void)7577 void nf_tables_trans_destroy_flush_work(void)
7578 {
7579 	flush_work(&trans_destroy_work);
7580 }
7581 EXPORT_SYMBOL_GPL(nf_tables_trans_destroy_flush_work);
7582 
nf_tables_commit_chain_prepare(struct net * net,struct nft_chain * chain)7583 static int nf_tables_commit_chain_prepare(struct net *net, struct nft_chain *chain)
7584 {
7585 	struct nft_rule *rule;
7586 	unsigned int alloc = 0;
7587 	int i;
7588 
7589 	/* already handled or inactive chain? */
7590 	if (chain->rules_next || !nft_is_active_next(net, chain))
7591 		return 0;
7592 
7593 	rule = list_entry(&chain->rules, struct nft_rule, list);
7594 	i = 0;
7595 
7596 	list_for_each_entry_continue(rule, &chain->rules, list) {
7597 		if (nft_is_active_next(net, rule))
7598 			alloc++;
7599 	}
7600 
7601 	chain->rules_next = nf_tables_chain_alloc_rules(chain, alloc);
7602 	if (!chain->rules_next)
7603 		return -ENOMEM;
7604 
7605 	list_for_each_entry_continue(rule, &chain->rules, list) {
7606 		if (nft_is_active_next(net, rule))
7607 			chain->rules_next[i++] = rule;
7608 	}
7609 
7610 	chain->rules_next[i] = NULL;
7611 	return 0;
7612 }
7613 
nf_tables_commit_chain_prepare_cancel(struct net * net)7614 static void nf_tables_commit_chain_prepare_cancel(struct net *net)
7615 {
7616 	struct nft_trans *trans, *next;
7617 
7618 	list_for_each_entry_safe(trans, next, &net->nft.commit_list, list) {
7619 		struct nft_chain *chain = trans->ctx.chain;
7620 
7621 		if (trans->msg_type == NFT_MSG_NEWRULE ||
7622 		    trans->msg_type == NFT_MSG_DELRULE) {
7623 			kvfree(chain->rules_next);
7624 			chain->rules_next = NULL;
7625 		}
7626 	}
7627 }
7628 
__nf_tables_commit_chain_free_rules_old(struct rcu_head * h)7629 static void __nf_tables_commit_chain_free_rules_old(struct rcu_head *h)
7630 {
7631 	struct nft_rules_old *o = container_of(h, struct nft_rules_old, h);
7632 
7633 	kvfree(o->start);
7634 }
7635 
nf_tables_commit_chain_free_rules_old(struct nft_rule ** rules)7636 static void nf_tables_commit_chain_free_rules_old(struct nft_rule **rules)
7637 {
7638 	struct nft_rule **r = rules;
7639 	struct nft_rules_old *old;
7640 
7641 	while (*r)
7642 		r++;
7643 
7644 	r++;	/* rcu_head is after end marker */
7645 	old = (void *) r;
7646 	old->start = rules;
7647 
7648 	call_rcu(&old->h, __nf_tables_commit_chain_free_rules_old);
7649 }
7650 
nf_tables_commit_chain(struct net * net,struct nft_chain * chain)7651 static void nf_tables_commit_chain(struct net *net, struct nft_chain *chain)
7652 {
7653 	struct nft_rule **g0, **g1;
7654 	bool next_genbit;
7655 
7656 	next_genbit = nft_gencursor_next(net);
7657 
7658 	g0 = rcu_dereference_protected(chain->rules_gen_0,
7659 				       lockdep_commit_lock_is_held(net));
7660 	g1 = rcu_dereference_protected(chain->rules_gen_1,
7661 				       lockdep_commit_lock_is_held(net));
7662 
7663 	/* No changes to this chain? */
7664 	if (chain->rules_next == NULL) {
7665 		/* chain had no change in last or next generation */
7666 		if (g0 == g1)
7667 			return;
7668 		/*
7669 		 * chain had no change in this generation; make sure next
7670 		 * one uses same rules as current generation.
7671 		 */
7672 		if (next_genbit) {
7673 			rcu_assign_pointer(chain->rules_gen_1, g0);
7674 			nf_tables_commit_chain_free_rules_old(g1);
7675 		} else {
7676 			rcu_assign_pointer(chain->rules_gen_0, g1);
7677 			nf_tables_commit_chain_free_rules_old(g0);
7678 		}
7679 
7680 		return;
7681 	}
7682 
7683 	if (next_genbit)
7684 		rcu_assign_pointer(chain->rules_gen_1, chain->rules_next);
7685 	else
7686 		rcu_assign_pointer(chain->rules_gen_0, chain->rules_next);
7687 
7688 	chain->rules_next = NULL;
7689 
7690 	if (g0 == g1)
7691 		return;
7692 
7693 	if (next_genbit)
7694 		nf_tables_commit_chain_free_rules_old(g1);
7695 	else
7696 		nf_tables_commit_chain_free_rules_old(g0);
7697 }
7698 
nft_obj_del(struct nft_object * obj)7699 static void nft_obj_del(struct nft_object *obj)
7700 {
7701 	rhltable_remove(&nft_objname_ht, &obj->rhlhead, nft_objname_ht_params);
7702 	list_del_rcu(&obj->list);
7703 }
7704 
nft_chain_del(struct nft_chain * chain)7705 void nft_chain_del(struct nft_chain *chain)
7706 {
7707 	struct nft_table *table = chain->table;
7708 
7709 	WARN_ON_ONCE(rhltable_remove(&table->chains_ht, &chain->rhlhead,
7710 				     nft_chain_ht_params));
7711 	list_del_rcu(&chain->list);
7712 }
7713 
nf_tables_module_autoload_cleanup(struct net * net)7714 static void nf_tables_module_autoload_cleanup(struct net *net)
7715 {
7716 	struct nft_module_request *req, *next;
7717 
7718 	WARN_ON_ONCE(!list_empty(&net->nft.commit_list));
7719 	list_for_each_entry_safe(req, next, &net->nft.module_list, list) {
7720 		WARN_ON_ONCE(!req->done);
7721 		list_del(&req->list);
7722 		kfree(req);
7723 	}
7724 }
7725 
nf_tables_commit_release(struct net * net)7726 static void nf_tables_commit_release(struct net *net)
7727 {
7728 	struct nft_trans *trans;
7729 
7730 	/* all side effects have to be made visible.
7731 	 * For example, if a chain named 'foo' has been deleted, a
7732 	 * new transaction must not find it anymore.
7733 	 *
7734 	 * Memory reclaim happens asynchronously from work queue
7735 	 * to prevent expensive synchronize_rcu() in commit phase.
7736 	 */
7737 	if (list_empty(&net->nft.commit_list)) {
7738 		nf_tables_module_autoload_cleanup(net);
7739 		mutex_unlock(&net->nft.commit_mutex);
7740 		return;
7741 	}
7742 
7743 	trans = list_last_entry(&net->nft.commit_list,
7744 				struct nft_trans, list);
7745 	get_net(trans->ctx.net);
7746 	WARN_ON_ONCE(trans->put_net);
7747 
7748 	trans->put_net = true;
7749 	spin_lock(&nf_tables_destroy_list_lock);
7750 	list_splice_tail_init(&net->nft.commit_list, &nf_tables_destroy_list);
7751 	spin_unlock(&nf_tables_destroy_list_lock);
7752 
7753 	nf_tables_module_autoload_cleanup(net);
7754 	schedule_work(&trans_destroy_work);
7755 
7756 	mutex_unlock(&net->nft.commit_mutex);
7757 }
7758 
nft_commit_notify(struct net * net,u32 portid)7759 static void nft_commit_notify(struct net *net, u32 portid)
7760 {
7761 	struct sk_buff *batch_skb = NULL, *nskb, *skb;
7762 	unsigned char *data;
7763 	int len;
7764 
7765 	list_for_each_entry_safe(skb, nskb, &net->nft.notify_list, list) {
7766 		if (!batch_skb) {
7767 new_batch:
7768 			batch_skb = skb;
7769 			len = NLMSG_GOODSIZE - skb->len;
7770 			list_del(&skb->list);
7771 			continue;
7772 		}
7773 		len -= skb->len;
7774 		if (len > 0 && NFT_CB(skb).report == NFT_CB(batch_skb).report) {
7775 			data = skb_put(batch_skb, skb->len);
7776 			memcpy(data, skb->data, skb->len);
7777 			list_del(&skb->list);
7778 			kfree_skb(skb);
7779 			continue;
7780 		}
7781 		nfnetlink_send(batch_skb, net, portid, NFNLGRP_NFTABLES,
7782 			       NFT_CB(batch_skb).report, GFP_KERNEL);
7783 		goto new_batch;
7784 	}
7785 
7786 	if (batch_skb) {
7787 		nfnetlink_send(batch_skb, net, portid, NFNLGRP_NFTABLES,
7788 			       NFT_CB(batch_skb).report, GFP_KERNEL);
7789 	}
7790 
7791 	WARN_ON_ONCE(!list_empty(&net->nft.notify_list));
7792 }
7793 
nf_tables_commit_audit_alloc(struct list_head * adl,struct nft_table * table)7794 static int nf_tables_commit_audit_alloc(struct list_head *adl,
7795 					struct nft_table *table)
7796 {
7797 	struct nft_audit_data *adp;
7798 
7799 	list_for_each_entry(adp, adl, list) {
7800 		if (adp->table == table)
7801 			return 0;
7802 	}
7803 	adp = kzalloc(sizeof(*adp), GFP_KERNEL);
7804 	if (!adp)
7805 		return -ENOMEM;
7806 	adp->table = table;
7807 	list_add(&adp->list, adl);
7808 	return 0;
7809 }
7810 
nf_tables_commit_audit_free(struct list_head * adl)7811 static void nf_tables_commit_audit_free(struct list_head *adl)
7812 {
7813 	struct nft_audit_data *adp, *adn;
7814 
7815 	list_for_each_entry_safe(adp, adn, adl, list) {
7816 		list_del(&adp->list);
7817 		kfree(adp);
7818 	}
7819 }
7820 
nf_tables_commit_audit_collect(struct list_head * adl,struct nft_table * table,u32 op)7821 static void nf_tables_commit_audit_collect(struct list_head *adl,
7822 					   struct nft_table *table, u32 op)
7823 {
7824 	struct nft_audit_data *adp;
7825 
7826 	list_for_each_entry(adp, adl, list) {
7827 		if (adp->table == table)
7828 			goto found;
7829 	}
7830 	WARN_ONCE(1, "table=%s not expected in commit list", table->name);
7831 	return;
7832 found:
7833 	adp->entries++;
7834 	if (!adp->op || adp->op > op)
7835 		adp->op = op;
7836 }
7837 
7838 #define AUNFTABLENAMELEN (NFT_TABLE_MAXNAMELEN + 22)
7839 
nf_tables_commit_audit_log(struct list_head * adl,u32 generation)7840 static void nf_tables_commit_audit_log(struct list_head *adl, u32 generation)
7841 {
7842 	struct nft_audit_data *adp, *adn;
7843 	char aubuf[AUNFTABLENAMELEN];
7844 
7845 	list_for_each_entry_safe(adp, adn, adl, list) {
7846 		snprintf(aubuf, AUNFTABLENAMELEN, "%s:%u", adp->table->name,
7847 			 generation);
7848 		audit_log_nfcfg(aubuf, adp->table->family, adp->entries,
7849 				nft2audit_op[adp->op], GFP_KERNEL);
7850 		list_del(&adp->list);
7851 		kfree(adp);
7852 	}
7853 }
7854 
nf_tables_commit(struct net * net,struct sk_buff * skb)7855 static int nf_tables_commit(struct net *net, struct sk_buff *skb)
7856 {
7857 	struct nft_trans *trans, *next;
7858 	struct nft_trans_elem *te;
7859 	struct nft_chain *chain;
7860 	struct nft_table *table;
7861 	LIST_HEAD(adl);
7862 	int err;
7863 
7864 	if (list_empty(&net->nft.commit_list)) {
7865 		mutex_unlock(&net->nft.commit_mutex);
7866 		return 0;
7867 	}
7868 
7869 	/* 0. Validate ruleset, otherwise roll back for error reporting. */
7870 	if (nf_tables_validate(net) < 0)
7871 		return -EAGAIN;
7872 
7873 	err = nft_flow_rule_offload_commit(net);
7874 	if (err < 0)
7875 		return err;
7876 
7877 	/* 1.  Allocate space for next generation rules_gen_X[] */
7878 	list_for_each_entry_safe(trans, next, &net->nft.commit_list, list) {
7879 		int ret;
7880 
7881 		ret = nf_tables_commit_audit_alloc(&adl, trans->ctx.table);
7882 		if (ret) {
7883 			nf_tables_commit_chain_prepare_cancel(net);
7884 			nf_tables_commit_audit_free(&adl);
7885 			return ret;
7886 		}
7887 		if (trans->msg_type == NFT_MSG_NEWRULE ||
7888 		    trans->msg_type == NFT_MSG_DELRULE) {
7889 			chain = trans->ctx.chain;
7890 
7891 			ret = nf_tables_commit_chain_prepare(net, chain);
7892 			if (ret < 0) {
7893 				nf_tables_commit_chain_prepare_cancel(net);
7894 				nf_tables_commit_audit_free(&adl);
7895 				return ret;
7896 			}
7897 		}
7898 	}
7899 
7900 	/* step 2.  Make rules_gen_X visible to packet path */
7901 	list_for_each_entry(table, &net->nft.tables, list) {
7902 		list_for_each_entry(chain, &table->chains, list)
7903 			nf_tables_commit_chain(net, chain);
7904 	}
7905 
7906 	/*
7907 	 * Bump generation counter, invalidate any dump in progress.
7908 	 * Cannot fail after this point.
7909 	 */
7910 	while (++net->nft.base_seq == 0);
7911 
7912 	/* step 3. Start new generation, rules_gen_X now in use. */
7913 	net->nft.gencursor = nft_gencursor_next(net);
7914 
7915 	list_for_each_entry_safe(trans, next, &net->nft.commit_list, list) {
7916 		nf_tables_commit_audit_collect(&adl, trans->ctx.table,
7917 					       trans->msg_type);
7918 		switch (trans->msg_type) {
7919 		case NFT_MSG_NEWTABLE:
7920 			if (nft_trans_table_update(trans)) {
7921 				if (!nft_trans_table_enable(trans)) {
7922 					nf_tables_table_disable(net,
7923 								trans->ctx.table);
7924 					trans->ctx.table->flags |= NFT_TABLE_F_DORMANT;
7925 				}
7926 			} else {
7927 				nft_clear(net, trans->ctx.table);
7928 			}
7929 			nf_tables_table_notify(&trans->ctx, NFT_MSG_NEWTABLE);
7930 			nft_trans_destroy(trans);
7931 			break;
7932 		case NFT_MSG_DELTABLE:
7933 			list_del_rcu(&trans->ctx.table->list);
7934 			nf_tables_table_notify(&trans->ctx, NFT_MSG_DELTABLE);
7935 			break;
7936 		case NFT_MSG_NEWCHAIN:
7937 			if (nft_trans_chain_update(trans)) {
7938 				nft_chain_commit_update(trans);
7939 				nf_tables_chain_notify(&trans->ctx, NFT_MSG_NEWCHAIN);
7940 				/* trans destroyed after rcu grace period */
7941 			} else {
7942 				nft_chain_commit_drop_policy(trans);
7943 				nft_clear(net, trans->ctx.chain);
7944 				nf_tables_chain_notify(&trans->ctx, NFT_MSG_NEWCHAIN);
7945 				nft_trans_destroy(trans);
7946 			}
7947 			break;
7948 		case NFT_MSG_DELCHAIN:
7949 			nft_chain_del(trans->ctx.chain);
7950 			nf_tables_chain_notify(&trans->ctx, NFT_MSG_DELCHAIN);
7951 			nf_tables_unregister_hook(trans->ctx.net,
7952 						  trans->ctx.table,
7953 						  trans->ctx.chain);
7954 			break;
7955 		case NFT_MSG_NEWRULE:
7956 			nft_clear(trans->ctx.net, nft_trans_rule(trans));
7957 			nf_tables_rule_notify(&trans->ctx,
7958 					      nft_trans_rule(trans),
7959 					      NFT_MSG_NEWRULE);
7960 			if (trans->ctx.chain->flags & NFT_CHAIN_HW_OFFLOAD)
7961 				nft_flow_rule_destroy(nft_trans_flow_rule(trans));
7962 
7963 			nft_trans_destroy(trans);
7964 			break;
7965 		case NFT_MSG_DELRULE:
7966 			list_del_rcu(&nft_trans_rule(trans)->list);
7967 			nf_tables_rule_notify(&trans->ctx,
7968 					      nft_trans_rule(trans),
7969 					      NFT_MSG_DELRULE);
7970 			nft_rule_expr_deactivate(&trans->ctx,
7971 						 nft_trans_rule(trans),
7972 						 NFT_TRANS_COMMIT);
7973 
7974 			if (trans->ctx.chain->flags & NFT_CHAIN_HW_OFFLOAD)
7975 				nft_flow_rule_destroy(nft_trans_flow_rule(trans));
7976 			break;
7977 		case NFT_MSG_NEWSET:
7978 			nft_clear(net, nft_trans_set(trans));
7979 			/* This avoids hitting -EBUSY when deleting the table
7980 			 * from the transaction.
7981 			 */
7982 			if (nft_set_is_anonymous(nft_trans_set(trans)) &&
7983 			    !list_empty(&nft_trans_set(trans)->bindings))
7984 				trans->ctx.table->use--;
7985 
7986 			nf_tables_set_notify(&trans->ctx, nft_trans_set(trans),
7987 					     NFT_MSG_NEWSET, GFP_KERNEL);
7988 			nft_trans_destroy(trans);
7989 			break;
7990 		case NFT_MSG_DELSET:
7991 			list_del_rcu(&nft_trans_set(trans)->list);
7992 			nf_tables_set_notify(&trans->ctx, nft_trans_set(trans),
7993 					     NFT_MSG_DELSET, GFP_KERNEL);
7994 			break;
7995 		case NFT_MSG_NEWSETELEM:
7996 			te = (struct nft_trans_elem *)trans->data;
7997 
7998 			te->set->ops->activate(net, te->set, &te->elem);
7999 			nf_tables_setelem_notify(&trans->ctx, te->set,
8000 						 &te->elem,
8001 						 NFT_MSG_NEWSETELEM, 0);
8002 			nft_trans_destroy(trans);
8003 			break;
8004 		case NFT_MSG_DELSETELEM:
8005 			te = (struct nft_trans_elem *)trans->data;
8006 
8007 			nf_tables_setelem_notify(&trans->ctx, te->set,
8008 						 &te->elem,
8009 						 NFT_MSG_DELSETELEM, 0);
8010 			te->set->ops->remove(net, te->set, &te->elem);
8011 			atomic_dec(&te->set->nelems);
8012 			te->set->ndeact--;
8013 			break;
8014 		case NFT_MSG_NEWOBJ:
8015 			if (nft_trans_obj_update(trans)) {
8016 				nft_obj_commit_update(trans);
8017 				nf_tables_obj_notify(&trans->ctx,
8018 						     nft_trans_obj(trans),
8019 						     NFT_MSG_NEWOBJ);
8020 			} else {
8021 				nft_clear(net, nft_trans_obj(trans));
8022 				nf_tables_obj_notify(&trans->ctx,
8023 						     nft_trans_obj(trans),
8024 						     NFT_MSG_NEWOBJ);
8025 				nft_trans_destroy(trans);
8026 			}
8027 			break;
8028 		case NFT_MSG_DELOBJ:
8029 			nft_obj_del(nft_trans_obj(trans));
8030 			nf_tables_obj_notify(&trans->ctx, nft_trans_obj(trans),
8031 					     NFT_MSG_DELOBJ);
8032 			break;
8033 		case NFT_MSG_NEWFLOWTABLE:
8034 			if (nft_trans_flowtable_update(trans)) {
8035 				nft_trans_flowtable(trans)->data.flags =
8036 					nft_trans_flowtable_flags(trans);
8037 				nf_tables_flowtable_notify(&trans->ctx,
8038 							   nft_trans_flowtable(trans),
8039 							   &nft_trans_flowtable_hooks(trans),
8040 							   NFT_MSG_NEWFLOWTABLE);
8041 				list_splice(&nft_trans_flowtable_hooks(trans),
8042 					    &nft_trans_flowtable(trans)->hook_list);
8043 			} else {
8044 				nft_clear(net, nft_trans_flowtable(trans));
8045 				nf_tables_flowtable_notify(&trans->ctx,
8046 							   nft_trans_flowtable(trans),
8047 							   &nft_trans_flowtable(trans)->hook_list,
8048 							   NFT_MSG_NEWFLOWTABLE);
8049 			}
8050 			nft_trans_destroy(trans);
8051 			break;
8052 		case NFT_MSG_DELFLOWTABLE:
8053 			if (nft_trans_flowtable_update(trans)) {
8054 				nf_tables_flowtable_notify(&trans->ctx,
8055 							   nft_trans_flowtable(trans),
8056 							   &nft_trans_flowtable_hooks(trans),
8057 							   NFT_MSG_DELFLOWTABLE);
8058 				nft_unregister_flowtable_net_hooks(net,
8059 								   &nft_trans_flowtable_hooks(trans));
8060 			} else {
8061 				list_del_rcu(&nft_trans_flowtable(trans)->list);
8062 				nf_tables_flowtable_notify(&trans->ctx,
8063 							   nft_trans_flowtable(trans),
8064 							   &nft_trans_flowtable(trans)->hook_list,
8065 							   NFT_MSG_DELFLOWTABLE);
8066 				nft_unregister_flowtable_net_hooks(net,
8067 						&nft_trans_flowtable(trans)->hook_list);
8068 			}
8069 			break;
8070 		}
8071 	}
8072 
8073 	nft_commit_notify(net, NETLINK_CB(skb).portid);
8074 	nf_tables_gen_notify(net, skb, NFT_MSG_NEWGEN);
8075 	nf_tables_commit_audit_log(&adl, net->nft.base_seq);
8076 	nf_tables_commit_release(net);
8077 
8078 	return 0;
8079 }
8080 
nf_tables_module_autoload(struct net * net)8081 static void nf_tables_module_autoload(struct net *net)
8082 {
8083 	struct nft_module_request *req, *next;
8084 	LIST_HEAD(module_list);
8085 
8086 	list_splice_init(&net->nft.module_list, &module_list);
8087 	mutex_unlock(&net->nft.commit_mutex);
8088 	list_for_each_entry_safe(req, next, &module_list, list) {
8089 		request_module("%s", req->module);
8090 		req->done = true;
8091 	}
8092 	mutex_lock(&net->nft.commit_mutex);
8093 	list_splice(&module_list, &net->nft.module_list);
8094 }
8095 
nf_tables_abort_release(struct nft_trans * trans)8096 static void nf_tables_abort_release(struct nft_trans *trans)
8097 {
8098 	switch (trans->msg_type) {
8099 	case NFT_MSG_NEWTABLE:
8100 		nf_tables_table_destroy(&trans->ctx);
8101 		break;
8102 	case NFT_MSG_NEWCHAIN:
8103 		nf_tables_chain_destroy(&trans->ctx);
8104 		break;
8105 	case NFT_MSG_NEWRULE:
8106 		nf_tables_rule_destroy(&trans->ctx, nft_trans_rule(trans));
8107 		break;
8108 	case NFT_MSG_NEWSET:
8109 		nft_set_destroy(&trans->ctx, nft_trans_set(trans));
8110 		break;
8111 	case NFT_MSG_NEWSETELEM:
8112 		nft_set_elem_destroy(nft_trans_elem_set(trans),
8113 				     nft_trans_elem(trans).priv, true);
8114 		break;
8115 	case NFT_MSG_NEWOBJ:
8116 		nft_obj_destroy(&trans->ctx, nft_trans_obj(trans));
8117 		break;
8118 	case NFT_MSG_NEWFLOWTABLE:
8119 		if (nft_trans_flowtable_update(trans))
8120 			nft_flowtable_hooks_destroy(&nft_trans_flowtable_hooks(trans));
8121 		else
8122 			nf_tables_flowtable_destroy(nft_trans_flowtable(trans));
8123 		break;
8124 	}
8125 	kfree(trans);
8126 }
8127 
__nf_tables_abort(struct net * net,enum nfnl_abort_action action)8128 static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action)
8129 {
8130 	struct nft_trans *trans, *next;
8131 	struct nft_trans_elem *te;
8132 
8133 	if (action == NFNL_ABORT_VALIDATE &&
8134 	    nf_tables_validate(net) < 0)
8135 		return -EAGAIN;
8136 
8137 	list_for_each_entry_safe_reverse(trans, next, &net->nft.commit_list,
8138 					 list) {
8139 		switch (trans->msg_type) {
8140 		case NFT_MSG_NEWTABLE:
8141 			if (nft_trans_table_update(trans)) {
8142 				if (nft_trans_table_enable(trans)) {
8143 					nf_tables_table_disable(net,
8144 								trans->ctx.table);
8145 					trans->ctx.table->flags |= NFT_TABLE_F_DORMANT;
8146 				}
8147 				nft_trans_destroy(trans);
8148 			} else {
8149 				list_del_rcu(&trans->ctx.table->list);
8150 			}
8151 			break;
8152 		case NFT_MSG_DELTABLE:
8153 			nft_clear(trans->ctx.net, trans->ctx.table);
8154 			nft_trans_destroy(trans);
8155 			break;
8156 		case NFT_MSG_NEWCHAIN:
8157 			if (nft_trans_chain_update(trans)) {
8158 				free_percpu(nft_trans_chain_stats(trans));
8159 				kfree(nft_trans_chain_name(trans));
8160 				nft_trans_destroy(trans);
8161 			} else {
8162 				if (nft_chain_is_bound(trans->ctx.chain)) {
8163 					nft_trans_destroy(trans);
8164 					break;
8165 				}
8166 				trans->ctx.table->use--;
8167 				nft_chain_del(trans->ctx.chain);
8168 				nf_tables_unregister_hook(trans->ctx.net,
8169 							  trans->ctx.table,
8170 							  trans->ctx.chain);
8171 			}
8172 			break;
8173 		case NFT_MSG_DELCHAIN:
8174 			trans->ctx.table->use++;
8175 			nft_clear(trans->ctx.net, trans->ctx.chain);
8176 			nft_trans_destroy(trans);
8177 			break;
8178 		case NFT_MSG_NEWRULE:
8179 			trans->ctx.chain->use--;
8180 			list_del_rcu(&nft_trans_rule(trans)->list);
8181 			nft_rule_expr_deactivate(&trans->ctx,
8182 						 nft_trans_rule(trans),
8183 						 NFT_TRANS_ABORT);
8184 			break;
8185 		case NFT_MSG_DELRULE:
8186 			trans->ctx.chain->use++;
8187 			nft_clear(trans->ctx.net, nft_trans_rule(trans));
8188 			nft_rule_expr_activate(&trans->ctx, nft_trans_rule(trans));
8189 			nft_trans_destroy(trans);
8190 			break;
8191 		case NFT_MSG_NEWSET:
8192 			trans->ctx.table->use--;
8193 			if (nft_trans_set_bound(trans)) {
8194 				nft_trans_destroy(trans);
8195 				break;
8196 			}
8197 			list_del_rcu(&nft_trans_set(trans)->list);
8198 			break;
8199 		case NFT_MSG_DELSET:
8200 			trans->ctx.table->use++;
8201 			nft_clear(trans->ctx.net, nft_trans_set(trans));
8202 			nft_trans_destroy(trans);
8203 			break;
8204 		case NFT_MSG_NEWSETELEM:
8205 			if (nft_trans_elem_set_bound(trans)) {
8206 				nft_trans_destroy(trans);
8207 				break;
8208 			}
8209 			te = (struct nft_trans_elem *)trans->data;
8210 			te->set->ops->remove(net, te->set, &te->elem);
8211 			atomic_dec(&te->set->nelems);
8212 			break;
8213 		case NFT_MSG_DELSETELEM:
8214 			te = (struct nft_trans_elem *)trans->data;
8215 
8216 			nft_set_elem_activate(net, te->set, &te->elem);
8217 			te->set->ops->activate(net, te->set, &te->elem);
8218 			te->set->ndeact--;
8219 
8220 			nft_trans_destroy(trans);
8221 			break;
8222 		case NFT_MSG_NEWOBJ:
8223 			if (nft_trans_obj_update(trans)) {
8224 				nft_obj_destroy(&trans->ctx, nft_trans_obj_newobj(trans));
8225 				nft_trans_destroy(trans);
8226 			} else {
8227 				trans->ctx.table->use--;
8228 				nft_obj_del(nft_trans_obj(trans));
8229 			}
8230 			break;
8231 		case NFT_MSG_DELOBJ:
8232 			trans->ctx.table->use++;
8233 			nft_clear(trans->ctx.net, nft_trans_obj(trans));
8234 			nft_trans_destroy(trans);
8235 			break;
8236 		case NFT_MSG_NEWFLOWTABLE:
8237 			if (nft_trans_flowtable_update(trans)) {
8238 				nft_unregister_flowtable_net_hooks(net,
8239 						&nft_trans_flowtable_hooks(trans));
8240 			} else {
8241 				trans->ctx.table->use--;
8242 				list_del_rcu(&nft_trans_flowtable(trans)->list);
8243 				nft_unregister_flowtable_net_hooks(net,
8244 						&nft_trans_flowtable(trans)->hook_list);
8245 			}
8246 			break;
8247 		case NFT_MSG_DELFLOWTABLE:
8248 			if (nft_trans_flowtable_update(trans)) {
8249 				list_splice(&nft_trans_flowtable_hooks(trans),
8250 					    &nft_trans_flowtable(trans)->hook_list);
8251 			} else {
8252 				trans->ctx.table->use++;
8253 				nft_clear(trans->ctx.net, nft_trans_flowtable(trans));
8254 			}
8255 			nft_trans_destroy(trans);
8256 			break;
8257 		}
8258 	}
8259 
8260 	synchronize_rcu();
8261 
8262 	list_for_each_entry_safe_reverse(trans, next,
8263 					 &net->nft.commit_list, list) {
8264 		list_del(&trans->list);
8265 		nf_tables_abort_release(trans);
8266 	}
8267 
8268 	if (action == NFNL_ABORT_AUTOLOAD)
8269 		nf_tables_module_autoload(net);
8270 	else
8271 		nf_tables_module_autoload_cleanup(net);
8272 
8273 	return 0;
8274 }
8275 
nf_tables_cleanup(struct net * net)8276 static void nf_tables_cleanup(struct net *net)
8277 {
8278 	nft_validate_state_update(net, NFT_VALIDATE_SKIP);
8279 }
8280 
nf_tables_abort(struct net * net,struct sk_buff * skb,enum nfnl_abort_action action)8281 static int nf_tables_abort(struct net *net, struct sk_buff *skb,
8282 			   enum nfnl_abort_action action)
8283 {
8284 	int ret = __nf_tables_abort(net, action);
8285 
8286 	mutex_unlock(&net->nft.commit_mutex);
8287 
8288 	return ret;
8289 }
8290 
nf_tables_valid_genid(struct net * net,u32 genid)8291 static bool nf_tables_valid_genid(struct net *net, u32 genid)
8292 {
8293 	bool genid_ok;
8294 
8295 	mutex_lock(&net->nft.commit_mutex);
8296 
8297 	genid_ok = genid == 0 || net->nft.base_seq == genid;
8298 	if (!genid_ok)
8299 		mutex_unlock(&net->nft.commit_mutex);
8300 
8301 	/* else, commit mutex has to be released by commit or abort function */
8302 	return genid_ok;
8303 }
8304 
8305 static const struct nfnetlink_subsystem nf_tables_subsys = {
8306 	.name		= "nf_tables",
8307 	.subsys_id	= NFNL_SUBSYS_NFTABLES,
8308 	.cb_count	= NFT_MSG_MAX,
8309 	.cb		= nf_tables_cb,
8310 	.commit		= nf_tables_commit,
8311 	.abort		= nf_tables_abort,
8312 	.cleanup	= nf_tables_cleanup,
8313 	.valid_genid	= nf_tables_valid_genid,
8314 	.owner		= THIS_MODULE,
8315 };
8316 
nft_chain_validate_dependency(const struct nft_chain * chain,enum nft_chain_types type)8317 int nft_chain_validate_dependency(const struct nft_chain *chain,
8318 				  enum nft_chain_types type)
8319 {
8320 	const struct nft_base_chain *basechain;
8321 
8322 	if (nft_is_base_chain(chain)) {
8323 		basechain = nft_base_chain(chain);
8324 		if (basechain->type->type != type)
8325 			return -EOPNOTSUPP;
8326 	}
8327 	return 0;
8328 }
8329 EXPORT_SYMBOL_GPL(nft_chain_validate_dependency);
8330 
nft_chain_validate_hooks(const struct nft_chain * chain,unsigned int hook_flags)8331 int nft_chain_validate_hooks(const struct nft_chain *chain,
8332 			     unsigned int hook_flags)
8333 {
8334 	struct nft_base_chain *basechain;
8335 
8336 	if (nft_is_base_chain(chain)) {
8337 		basechain = nft_base_chain(chain);
8338 
8339 		if ((1 << basechain->ops.hooknum) & hook_flags)
8340 			return 0;
8341 
8342 		return -EOPNOTSUPP;
8343 	}
8344 
8345 	return 0;
8346 }
8347 EXPORT_SYMBOL_GPL(nft_chain_validate_hooks);
8348 
8349 /*
8350  * Loop detection - walk through the ruleset beginning at the destination chain
8351  * of a new jump until either the source chain is reached (loop) or all
8352  * reachable chains have been traversed.
8353  *
8354  * The loop check is performed whenever a new jump verdict is added to an
8355  * expression or verdict map or a verdict map is bound to a new chain.
8356  */
8357 
8358 static int nf_tables_check_loops(const struct nft_ctx *ctx,
8359 				 const struct nft_chain *chain);
8360 
nf_tables_loop_check_setelem(const struct nft_ctx * ctx,struct nft_set * set,const struct nft_set_iter * iter,struct nft_set_elem * elem)8361 static int nf_tables_loop_check_setelem(const struct nft_ctx *ctx,
8362 					struct nft_set *set,
8363 					const struct nft_set_iter *iter,
8364 					struct nft_set_elem *elem)
8365 {
8366 	const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
8367 	const struct nft_data *data;
8368 
8369 	if (nft_set_ext_exists(ext, NFT_SET_EXT_FLAGS) &&
8370 	    *nft_set_ext_flags(ext) & NFT_SET_ELEM_INTERVAL_END)
8371 		return 0;
8372 
8373 	data = nft_set_ext_data(ext);
8374 	switch (data->verdict.code) {
8375 	case NFT_JUMP:
8376 	case NFT_GOTO:
8377 		return nf_tables_check_loops(ctx, data->verdict.chain);
8378 	default:
8379 		return 0;
8380 	}
8381 }
8382 
nf_tables_check_loops(const struct nft_ctx * ctx,const struct nft_chain * chain)8383 static int nf_tables_check_loops(const struct nft_ctx *ctx,
8384 				 const struct nft_chain *chain)
8385 {
8386 	const struct nft_rule *rule;
8387 	const struct nft_expr *expr, *last;
8388 	struct nft_set *set;
8389 	struct nft_set_binding *binding;
8390 	struct nft_set_iter iter;
8391 
8392 	if (ctx->chain == chain)
8393 		return -ELOOP;
8394 
8395 	list_for_each_entry(rule, &chain->rules, list) {
8396 		nft_rule_for_each_expr(expr, last, rule) {
8397 			struct nft_immediate_expr *priv;
8398 			const struct nft_data *data;
8399 			int err;
8400 
8401 			if (strcmp(expr->ops->type->name, "immediate"))
8402 				continue;
8403 
8404 			priv = nft_expr_priv(expr);
8405 			if (priv->dreg != NFT_REG_VERDICT)
8406 				continue;
8407 
8408 			data = &priv->data;
8409 			switch (data->verdict.code) {
8410 			case NFT_JUMP:
8411 			case NFT_GOTO:
8412 				err = nf_tables_check_loops(ctx,
8413 							data->verdict.chain);
8414 				if (err < 0)
8415 					return err;
8416 				break;
8417 			default:
8418 				break;
8419 			}
8420 		}
8421 	}
8422 
8423 	list_for_each_entry(set, &ctx->table->sets, list) {
8424 		if (!nft_is_active_next(ctx->net, set))
8425 			continue;
8426 		if (!(set->flags & NFT_SET_MAP) ||
8427 		    set->dtype != NFT_DATA_VERDICT)
8428 			continue;
8429 
8430 		list_for_each_entry(binding, &set->bindings, list) {
8431 			if (!(binding->flags & NFT_SET_MAP) ||
8432 			    binding->chain != chain)
8433 				continue;
8434 
8435 			iter.genmask	= nft_genmask_next(ctx->net);
8436 			iter.skip 	= 0;
8437 			iter.count	= 0;
8438 			iter.err	= 0;
8439 			iter.fn		= nf_tables_loop_check_setelem;
8440 
8441 			set->ops->walk(ctx, set, &iter);
8442 			if (iter.err < 0)
8443 				return iter.err;
8444 		}
8445 	}
8446 
8447 	return 0;
8448 }
8449 
8450 /**
8451  *	nft_parse_u32_check - fetch u32 attribute and check for maximum value
8452  *
8453  *	@attr: netlink attribute to fetch value from
8454  *	@max: maximum value to be stored in dest
8455  *	@dest: pointer to the variable
8456  *
8457  *	Parse, check and store a given u32 netlink attribute into variable.
8458  *	This function returns -ERANGE if the value goes over maximum value.
8459  *	Otherwise a 0 is returned and the attribute value is stored in the
8460  *	destination variable.
8461  */
nft_parse_u32_check(const struct nlattr * attr,int max,u32 * dest)8462 int nft_parse_u32_check(const struct nlattr *attr, int max, u32 *dest)
8463 {
8464 	u32 val;
8465 
8466 	val = ntohl(nla_get_be32(attr));
8467 	if (val > max)
8468 		return -ERANGE;
8469 
8470 	*dest = val;
8471 	return 0;
8472 }
8473 EXPORT_SYMBOL_GPL(nft_parse_u32_check);
8474 
8475 /**
8476  *	nft_parse_register - parse a register value from a netlink attribute
8477  *
8478  *	@attr: netlink attribute
8479  *
8480  *	Parse and translate a register value from a netlink attribute.
8481  *	Registers used to be 128 bit wide, these register numbers will be
8482  *	mapped to the corresponding 32 bit register numbers.
8483  */
nft_parse_register(const struct nlattr * attr)8484 unsigned int nft_parse_register(const struct nlattr *attr)
8485 {
8486 	unsigned int reg;
8487 
8488 	reg = ntohl(nla_get_be32(attr));
8489 	switch (reg) {
8490 	case NFT_REG_VERDICT...NFT_REG_4:
8491 		return reg * NFT_REG_SIZE / NFT_REG32_SIZE;
8492 	default:
8493 		return reg + NFT_REG_SIZE / NFT_REG32_SIZE - NFT_REG32_00;
8494 	}
8495 }
8496 EXPORT_SYMBOL_GPL(nft_parse_register);
8497 
8498 /**
8499  *	nft_dump_register - dump a register value to a netlink attribute
8500  *
8501  *	@skb: socket buffer
8502  *	@attr: attribute number
8503  *	@reg: register number
8504  *
8505  *	Construct a netlink attribute containing the register number. For
8506  *	compatibility reasons, register numbers being a multiple of 4 are
8507  *	translated to the corresponding 128 bit register numbers.
8508  */
nft_dump_register(struct sk_buff * skb,unsigned int attr,unsigned int reg)8509 int nft_dump_register(struct sk_buff *skb, unsigned int attr, unsigned int reg)
8510 {
8511 	if (reg % (NFT_REG_SIZE / NFT_REG32_SIZE) == 0)
8512 		reg = reg / (NFT_REG_SIZE / NFT_REG32_SIZE);
8513 	else
8514 		reg = reg - NFT_REG_SIZE / NFT_REG32_SIZE + NFT_REG32_00;
8515 
8516 	return nla_put_be32(skb, attr, htonl(reg));
8517 }
8518 EXPORT_SYMBOL_GPL(nft_dump_register);
8519 
8520 /**
8521  *	nft_validate_register_load - validate a load from a register
8522  *
8523  *	@reg: the register number
8524  *	@len: the length of the data
8525  *
8526  * 	Validate that the input register is one of the general purpose
8527  * 	registers and that the length of the load is within the bounds.
8528  */
nft_validate_register_load(enum nft_registers reg,unsigned int len)8529 static int nft_validate_register_load(enum nft_registers reg, unsigned int len)
8530 {
8531 	if (reg < NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE)
8532 		return -EINVAL;
8533 	if (len == 0)
8534 		return -EINVAL;
8535 	if (reg * NFT_REG32_SIZE + len > sizeof_field(struct nft_regs, data))
8536 		return -ERANGE;
8537 
8538 	return 0;
8539 }
8540 
nft_parse_register_load(const struct nlattr * attr,u8 * sreg,u32 len)8541 int nft_parse_register_load(const struct nlattr *attr, u8 *sreg, u32 len)
8542 {
8543 	u32 reg;
8544 	int err;
8545 
8546 	reg = nft_parse_register(attr);
8547 	err = nft_validate_register_load(reg, len);
8548 	if (err < 0)
8549 		return err;
8550 
8551 	*sreg = reg;
8552 	return 0;
8553 }
8554 EXPORT_SYMBOL_GPL(nft_parse_register_load);
8555 
8556 /**
8557  *	nft_validate_register_store - validate an expressions' register store
8558  *
8559  *	@ctx: context of the expression performing the load
8560  * 	@reg: the destination register number
8561  * 	@data: the data to load
8562  * 	@type: the data type
8563  * 	@len: the length of the data
8564  *
8565  * 	Validate that a data load uses the appropriate data type for
8566  * 	the destination register and the length is within the bounds.
8567  * 	A value of NULL for the data means that its runtime gathered
8568  * 	data.
8569  */
nft_validate_register_store(const struct nft_ctx * ctx,enum nft_registers reg,const struct nft_data * data,enum nft_data_types type,unsigned int len)8570 static int nft_validate_register_store(const struct nft_ctx *ctx,
8571 				       enum nft_registers reg,
8572 				       const struct nft_data *data,
8573 				       enum nft_data_types type,
8574 				       unsigned int len)
8575 {
8576 	int err;
8577 
8578 	switch (reg) {
8579 	case NFT_REG_VERDICT:
8580 		if (type != NFT_DATA_VERDICT)
8581 			return -EINVAL;
8582 
8583 		if (data != NULL &&
8584 		    (data->verdict.code == NFT_GOTO ||
8585 		     data->verdict.code == NFT_JUMP)) {
8586 			err = nf_tables_check_loops(ctx, data->verdict.chain);
8587 			if (err < 0)
8588 				return err;
8589 		}
8590 
8591 		return 0;
8592 	default:
8593 		if (reg < NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE)
8594 			return -EINVAL;
8595 		if (len == 0)
8596 			return -EINVAL;
8597 		if (reg * NFT_REG32_SIZE + len >
8598 		    sizeof_field(struct nft_regs, data))
8599 			return -ERANGE;
8600 
8601 		if (data != NULL && type != NFT_DATA_VALUE)
8602 			return -EINVAL;
8603 		return 0;
8604 	}
8605 }
8606 
nft_parse_register_store(const struct nft_ctx * ctx,const struct nlattr * attr,u8 * dreg,const struct nft_data * data,enum nft_data_types type,unsigned int len)8607 int nft_parse_register_store(const struct nft_ctx *ctx,
8608 			     const struct nlattr *attr, u8 *dreg,
8609 			     const struct nft_data *data,
8610 			     enum nft_data_types type, unsigned int len)
8611 {
8612 	int err;
8613 	u32 reg;
8614 
8615 	reg = nft_parse_register(attr);
8616 	err = nft_validate_register_store(ctx, reg, data, type, len);
8617 	if (err < 0)
8618 		return err;
8619 
8620 	*dreg = reg;
8621 	return 0;
8622 }
8623 EXPORT_SYMBOL_GPL(nft_parse_register_store);
8624 
8625 static const struct nla_policy nft_verdict_policy[NFTA_VERDICT_MAX + 1] = {
8626 	[NFTA_VERDICT_CODE]	= { .type = NLA_U32 },
8627 	[NFTA_VERDICT_CHAIN]	= { .type = NLA_STRING,
8628 				    .len = NFT_CHAIN_MAXNAMELEN - 1 },
8629 	[NFTA_VERDICT_CHAIN_ID]	= { .type = NLA_U32 },
8630 };
8631 
nft_verdict_init(const struct nft_ctx * ctx,struct nft_data * data,struct nft_data_desc * desc,const struct nlattr * nla)8632 static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data,
8633 			    struct nft_data_desc *desc, const struct nlattr *nla)
8634 {
8635 	u8 genmask = nft_genmask_next(ctx->net);
8636 	struct nlattr *tb[NFTA_VERDICT_MAX + 1];
8637 	struct nft_chain *chain;
8638 	int err;
8639 
8640 	err = nla_parse_nested_deprecated(tb, NFTA_VERDICT_MAX, nla,
8641 					  nft_verdict_policy, NULL);
8642 	if (err < 0)
8643 		return err;
8644 
8645 	if (!tb[NFTA_VERDICT_CODE])
8646 		return -EINVAL;
8647 	data->verdict.code = ntohl(nla_get_be32(tb[NFTA_VERDICT_CODE]));
8648 
8649 	switch (data->verdict.code) {
8650 	default:
8651 		switch (data->verdict.code & NF_VERDICT_MASK) {
8652 		case NF_ACCEPT:
8653 		case NF_DROP:
8654 		case NF_QUEUE:
8655 			break;
8656 		default:
8657 			return -EINVAL;
8658 		}
8659 		fallthrough;
8660 	case NFT_CONTINUE:
8661 	case NFT_BREAK:
8662 	case NFT_RETURN:
8663 		break;
8664 	case NFT_JUMP:
8665 	case NFT_GOTO:
8666 		if (tb[NFTA_VERDICT_CHAIN]) {
8667 			chain = nft_chain_lookup(ctx->net, ctx->table,
8668 						 tb[NFTA_VERDICT_CHAIN],
8669 						 genmask);
8670 		} else if (tb[NFTA_VERDICT_CHAIN_ID]) {
8671 			chain = nft_chain_lookup_byid(ctx->net, ctx->table,
8672 						      tb[NFTA_VERDICT_CHAIN_ID]);
8673 			if (IS_ERR(chain))
8674 				return PTR_ERR(chain);
8675 		} else {
8676 			return -EINVAL;
8677 		}
8678 
8679 		if (IS_ERR(chain))
8680 			return PTR_ERR(chain);
8681 		if (nft_is_base_chain(chain))
8682 			return -EOPNOTSUPP;
8683 		if (nft_chain_is_bound(chain))
8684 			return -EINVAL;
8685 		if (desc->flags & NFT_DATA_DESC_SETELEM &&
8686 		    chain->flags & NFT_CHAIN_BINDING)
8687 			return -EINVAL;
8688 
8689 		chain->use++;
8690 		data->verdict.chain = chain;
8691 		break;
8692 	}
8693 
8694 	desc->len = sizeof(data->verdict);
8695 
8696 	return 0;
8697 }
8698 
nft_verdict_uninit(const struct nft_data * data)8699 static void nft_verdict_uninit(const struct nft_data *data)
8700 {
8701 	struct nft_chain *chain;
8702 	struct nft_rule *rule;
8703 
8704 	switch (data->verdict.code) {
8705 	case NFT_JUMP:
8706 	case NFT_GOTO:
8707 		chain = data->verdict.chain;
8708 		chain->use--;
8709 
8710 		if (!nft_chain_is_bound(chain))
8711 			break;
8712 
8713 		chain->table->use--;
8714 		list_for_each_entry(rule, &chain->rules, list)
8715 			chain->use--;
8716 
8717 		nft_chain_del(chain);
8718 		break;
8719 	}
8720 }
8721 
nft_verdict_dump(struct sk_buff * skb,int type,const struct nft_verdict * v)8722 int nft_verdict_dump(struct sk_buff *skb, int type, const struct nft_verdict *v)
8723 {
8724 	struct nlattr *nest;
8725 
8726 	nest = nla_nest_start_noflag(skb, type);
8727 	if (!nest)
8728 		goto nla_put_failure;
8729 
8730 	if (nla_put_be32(skb, NFTA_VERDICT_CODE, htonl(v->code)))
8731 		goto nla_put_failure;
8732 
8733 	switch (v->code) {
8734 	case NFT_JUMP:
8735 	case NFT_GOTO:
8736 		if (nla_put_string(skb, NFTA_VERDICT_CHAIN,
8737 				   v->chain->name))
8738 			goto nla_put_failure;
8739 	}
8740 	nla_nest_end(skb, nest);
8741 	return 0;
8742 
8743 nla_put_failure:
8744 	return -1;
8745 }
8746 
nft_value_init(const struct nft_ctx * ctx,struct nft_data * data,struct nft_data_desc * desc,const struct nlattr * nla)8747 static int nft_value_init(const struct nft_ctx *ctx,
8748 			  struct nft_data *data, struct nft_data_desc *desc,
8749 			  const struct nlattr *nla)
8750 {
8751 	unsigned int len;
8752 
8753 	len = nla_len(nla);
8754 	if (len == 0)
8755 		return -EINVAL;
8756 	if (len > desc->size)
8757 		return -EOVERFLOW;
8758 	if (desc->len) {
8759 		if (len != desc->len)
8760 			return -EINVAL;
8761 	} else {
8762 		desc->len = len;
8763 	}
8764 
8765 	nla_memcpy(data->data, nla, len);
8766 
8767 	return 0;
8768 }
8769 
nft_value_dump(struct sk_buff * skb,const struct nft_data * data,unsigned int len)8770 static int nft_value_dump(struct sk_buff *skb, const struct nft_data *data,
8771 			  unsigned int len)
8772 {
8773 	return nla_put(skb, NFTA_DATA_VALUE, len, data->data);
8774 }
8775 
8776 static const struct nla_policy nft_data_policy[NFTA_DATA_MAX + 1] = {
8777 	[NFTA_DATA_VALUE]	= { .type = NLA_BINARY },
8778 	[NFTA_DATA_VERDICT]	= { .type = NLA_NESTED },
8779 };
8780 
8781 /**
8782  *	nft_data_init - parse nf_tables data netlink attributes
8783  *
8784  *	@ctx: context of the expression using the data
8785  *	@data: destination struct nft_data
8786  *	@desc: data description
8787  *	@nla: netlink attribute containing data
8788  *
8789  *	Parse the netlink data attributes and initialize a struct nft_data.
8790  *	The type and length of data are returned in the data description.
8791  *
8792  *	The caller can indicate that it only wants to accept data of type
8793  *	NFT_DATA_VALUE by passing NULL for the ctx argument.
8794  */
nft_data_init(const struct nft_ctx * ctx,struct nft_data * data,struct nft_data_desc * desc,const struct nlattr * nla)8795 int nft_data_init(const struct nft_ctx *ctx, struct nft_data *data,
8796 		  struct nft_data_desc *desc, const struct nlattr *nla)
8797 {
8798 	struct nlattr *tb[NFTA_DATA_MAX + 1];
8799 	int err;
8800 
8801 	if (WARN_ON_ONCE(!desc->size))
8802 		return -EINVAL;
8803 
8804 	err = nla_parse_nested_deprecated(tb, NFTA_DATA_MAX, nla,
8805 					  nft_data_policy, NULL);
8806 	if (err < 0)
8807 		return err;
8808 
8809 	if (tb[NFTA_DATA_VALUE]) {
8810 		if (desc->type != NFT_DATA_VALUE)
8811 			return -EINVAL;
8812 
8813 		err = nft_value_init(ctx, data, desc, tb[NFTA_DATA_VALUE]);
8814 	} else if (tb[NFTA_DATA_VERDICT] && ctx != NULL) {
8815 		if (desc->type != NFT_DATA_VERDICT)
8816 			return -EINVAL;
8817 
8818 		err = nft_verdict_init(ctx, data, desc, tb[NFTA_DATA_VERDICT]);
8819 	} else {
8820 		err = -EINVAL;
8821 	}
8822 
8823 	return err;
8824 }
8825 EXPORT_SYMBOL_GPL(nft_data_init);
8826 
8827 /**
8828  *	nft_data_release - release a nft_data item
8829  *
8830  *	@data: struct nft_data to release
8831  *	@type: type of data
8832  *
8833  *	Release a nft_data item. NFT_DATA_VALUE types can be silently discarded,
8834  *	all others need to be released by calling this function.
8835  */
nft_data_release(const struct nft_data * data,enum nft_data_types type)8836 void nft_data_release(const struct nft_data *data, enum nft_data_types type)
8837 {
8838 	if (type < NFT_DATA_VERDICT)
8839 		return;
8840 	switch (type) {
8841 	case NFT_DATA_VERDICT:
8842 		return nft_verdict_uninit(data);
8843 	default:
8844 		WARN_ON(1);
8845 	}
8846 }
8847 EXPORT_SYMBOL_GPL(nft_data_release);
8848 
nft_data_dump(struct sk_buff * skb,int attr,const struct nft_data * data,enum nft_data_types type,unsigned int len)8849 int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data,
8850 		  enum nft_data_types type, unsigned int len)
8851 {
8852 	struct nlattr *nest;
8853 	int err;
8854 
8855 	nest = nla_nest_start_noflag(skb, attr);
8856 	if (nest == NULL)
8857 		return -1;
8858 
8859 	switch (type) {
8860 	case NFT_DATA_VALUE:
8861 		err = nft_value_dump(skb, data, len);
8862 		break;
8863 	case NFT_DATA_VERDICT:
8864 		err = nft_verdict_dump(skb, NFTA_DATA_VERDICT, &data->verdict);
8865 		break;
8866 	default:
8867 		err = -EINVAL;
8868 		WARN_ON(1);
8869 	}
8870 
8871 	nla_nest_end(skb, nest);
8872 	return err;
8873 }
8874 EXPORT_SYMBOL_GPL(nft_data_dump);
8875 
__nft_release_basechain(struct nft_ctx * ctx)8876 int __nft_release_basechain(struct nft_ctx *ctx)
8877 {
8878 	struct nft_rule *rule, *nr;
8879 
8880 	if (WARN_ON(!nft_is_base_chain(ctx->chain)))
8881 		return 0;
8882 
8883 	nf_tables_unregister_hook(ctx->net, ctx->chain->table, ctx->chain);
8884 	list_for_each_entry_safe(rule, nr, &ctx->chain->rules, list) {
8885 		list_del(&rule->list);
8886 		ctx->chain->use--;
8887 		nf_tables_rule_release(ctx, rule);
8888 	}
8889 	nft_chain_del(ctx->chain);
8890 	ctx->table->use--;
8891 	nf_tables_chain_destroy(ctx);
8892 
8893 	return 0;
8894 }
8895 EXPORT_SYMBOL_GPL(__nft_release_basechain);
8896 
__nft_release_hooks(struct net * net)8897 static void __nft_release_hooks(struct net *net)
8898 {
8899 	struct nft_table *table;
8900 	struct nft_chain *chain;
8901 
8902 	list_for_each_entry(table, &net->nft.tables, list) {
8903 		list_for_each_entry(chain, &table->chains, list)
8904 			nf_tables_unregister_hook(net, table, chain);
8905 	}
8906 }
8907 
__nft_release_tables(struct net * net)8908 static void __nft_release_tables(struct net *net)
8909 {
8910 	struct nft_flowtable *flowtable, *nf;
8911 	struct nft_table *table, *nt;
8912 	struct nft_chain *chain, *nc;
8913 	struct nft_object *obj, *ne;
8914 	struct nft_rule *rule, *nr;
8915 	struct nft_set *set, *ns;
8916 	struct nft_ctx ctx = {
8917 		.net	= net,
8918 		.family	= NFPROTO_NETDEV,
8919 	};
8920 
8921 	list_for_each_entry_safe(table, nt, &net->nft.tables, list) {
8922 		ctx.family = table->family;
8923 		ctx.table = table;
8924 		list_for_each_entry(chain, &table->chains, list) {
8925 			ctx.chain = chain;
8926 			list_for_each_entry_safe(rule, nr, &chain->rules, list) {
8927 				list_del(&rule->list);
8928 				chain->use--;
8929 				nf_tables_rule_release(&ctx, rule);
8930 			}
8931 		}
8932 		list_for_each_entry_safe(flowtable, nf, &table->flowtables, list) {
8933 			list_del(&flowtable->list);
8934 			table->use--;
8935 			nf_tables_flowtable_destroy(flowtable);
8936 		}
8937 		list_for_each_entry_safe(set, ns, &table->sets, list) {
8938 			list_del(&set->list);
8939 			table->use--;
8940 			nft_set_destroy(&ctx, set);
8941 		}
8942 		list_for_each_entry_safe(obj, ne, &table->objects, list) {
8943 			nft_obj_del(obj);
8944 			table->use--;
8945 			nft_obj_destroy(&ctx, obj);
8946 		}
8947 		list_for_each_entry_safe(chain, nc, &table->chains, list) {
8948 			ctx.chain = chain;
8949 			nft_chain_del(chain);
8950 			table->use--;
8951 			nf_tables_chain_destroy(&ctx);
8952 		}
8953 		list_del(&table->list);
8954 		nf_tables_table_destroy(&ctx);
8955 	}
8956 }
8957 
nf_tables_init_net(struct net * net)8958 static int __net_init nf_tables_init_net(struct net *net)
8959 {
8960 	INIT_LIST_HEAD(&net->nft.tables);
8961 	INIT_LIST_HEAD(&net->nft.commit_list);
8962 	INIT_LIST_HEAD(&net->nft.module_list);
8963 	INIT_LIST_HEAD(&net->nft.notify_list);
8964 	mutex_init(&net->nft.commit_mutex);
8965 	net->nft.base_seq = 1;
8966 	net->nft.validate_state = NFT_VALIDATE_SKIP;
8967 
8968 	return 0;
8969 }
8970 
nf_tables_pre_exit_net(struct net * net)8971 static void __net_exit nf_tables_pre_exit_net(struct net *net)
8972 {
8973 	__nft_release_hooks(net);
8974 }
8975 
nf_tables_exit_net(struct net * net)8976 static void __net_exit nf_tables_exit_net(struct net *net)
8977 {
8978 	mutex_lock(&net->nft.commit_mutex);
8979 	if (!list_empty(&net->nft.commit_list))
8980 		__nf_tables_abort(net, NFNL_ABORT_NONE);
8981 	__nft_release_tables(net);
8982 	mutex_unlock(&net->nft.commit_mutex);
8983 	WARN_ON_ONCE(!list_empty(&net->nft.tables));
8984 	WARN_ON_ONCE(!list_empty(&net->nft.module_list));
8985 	WARN_ON_ONCE(!list_empty(&net->nft.notify_list));
8986 }
8987 
8988 static struct pernet_operations nf_tables_net_ops = {
8989 	.init		= nf_tables_init_net,
8990 	.pre_exit	= nf_tables_pre_exit_net,
8991 	.exit		= nf_tables_exit_net,
8992 };
8993 
nf_tables_module_init(void)8994 static int __init nf_tables_module_init(void)
8995 {
8996 	int err;
8997 
8998 	spin_lock_init(&nf_tables_destroy_list_lock);
8999 	err = register_pernet_subsys(&nf_tables_net_ops);
9000 	if (err < 0)
9001 		return err;
9002 
9003 	err = nft_chain_filter_init();
9004 	if (err < 0)
9005 		goto err1;
9006 
9007 	err = nf_tables_core_module_init();
9008 	if (err < 0)
9009 		goto err2;
9010 
9011 	err = register_netdevice_notifier(&nf_tables_flowtable_notifier);
9012 	if (err < 0)
9013 		goto err3;
9014 
9015 	err = rhltable_init(&nft_objname_ht, &nft_objname_ht_params);
9016 	if (err < 0)
9017 		goto err4;
9018 
9019 	err = nft_offload_init();
9020 	if (err < 0)
9021 		goto err5;
9022 
9023 	/* must be last */
9024 	err = nfnetlink_subsys_register(&nf_tables_subsys);
9025 	if (err < 0)
9026 		goto err6;
9027 
9028 	nft_chain_route_init();
9029 
9030 	return err;
9031 err6:
9032 	nft_offload_exit();
9033 err5:
9034 	rhltable_destroy(&nft_objname_ht);
9035 err4:
9036 	unregister_netdevice_notifier(&nf_tables_flowtable_notifier);
9037 err3:
9038 	nf_tables_core_module_exit();
9039 err2:
9040 	nft_chain_filter_fini();
9041 err1:
9042 	unregister_pernet_subsys(&nf_tables_net_ops);
9043 	return err;
9044 }
9045 
nf_tables_module_exit(void)9046 static void __exit nf_tables_module_exit(void)
9047 {
9048 	nfnetlink_subsys_unregister(&nf_tables_subsys);
9049 	nft_offload_exit();
9050 	unregister_netdevice_notifier(&nf_tables_flowtable_notifier);
9051 	nft_chain_filter_fini();
9052 	nft_chain_route_fini();
9053 	unregister_pernet_subsys(&nf_tables_net_ops);
9054 	cancel_work_sync(&trans_destroy_work);
9055 	rcu_barrier();
9056 	rhltable_destroy(&nft_objname_ht);
9057 	nf_tables_core_module_exit();
9058 }
9059 
9060 module_init(nf_tables_module_init);
9061 module_exit(nf_tables_module_exit);
9062 
9063 MODULE_LICENSE("GPL");
9064 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
9065 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_NFTABLES);
9066