1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * linux/fs/lockd/svcshare.c
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Management of DOS shares.
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Copyright (C) 1996 Olaf Kirch <okir@monad.swb.de>
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/time.h>
11*4882a593Smuzhiyun #include <linux/unistd.h>
12*4882a593Smuzhiyun #include <linux/string.h>
13*4882a593Smuzhiyun #include <linux/slab.h>
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun #include <linux/sunrpc/clnt.h>
16*4882a593Smuzhiyun #include <linux/sunrpc/svc.h>
17*4882a593Smuzhiyun #include <linux/lockd/lockd.h>
18*4882a593Smuzhiyun #include <linux/lockd/share.h>
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun static inline int
nlm_cmp_owner(struct nlm_share * share,struct xdr_netobj * oh)21*4882a593Smuzhiyun nlm_cmp_owner(struct nlm_share *share, struct xdr_netobj *oh)
22*4882a593Smuzhiyun {
23*4882a593Smuzhiyun return share->s_owner.len == oh->len
24*4882a593Smuzhiyun && !memcmp(share->s_owner.data, oh->data, oh->len);
25*4882a593Smuzhiyun }
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun __be32
nlmsvc_share_file(struct nlm_host * host,struct nlm_file * file,struct nlm_args * argp)28*4882a593Smuzhiyun nlmsvc_share_file(struct nlm_host *host, struct nlm_file *file,
29*4882a593Smuzhiyun struct nlm_args *argp)
30*4882a593Smuzhiyun {
31*4882a593Smuzhiyun struct nlm_share *share;
32*4882a593Smuzhiyun struct xdr_netobj *oh = &argp->lock.oh;
33*4882a593Smuzhiyun u8 *ohdata;
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun for (share = file->f_shares; share; share = share->s_next) {
36*4882a593Smuzhiyun if (share->s_host == host && nlm_cmp_owner(share, oh))
37*4882a593Smuzhiyun goto update;
38*4882a593Smuzhiyun if ((argp->fsm_access & share->s_mode)
39*4882a593Smuzhiyun || (argp->fsm_mode & share->s_access ))
40*4882a593Smuzhiyun return nlm_lck_denied;
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun share = kmalloc(sizeof(*share) + oh->len,
44*4882a593Smuzhiyun GFP_KERNEL);
45*4882a593Smuzhiyun if (share == NULL)
46*4882a593Smuzhiyun return nlm_lck_denied_nolocks;
47*4882a593Smuzhiyun
48*4882a593Smuzhiyun /* Copy owner handle */
49*4882a593Smuzhiyun ohdata = (u8 *) (share + 1);
50*4882a593Smuzhiyun memcpy(ohdata, oh->data, oh->len);
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun share->s_file = file;
53*4882a593Smuzhiyun share->s_host = host;
54*4882a593Smuzhiyun share->s_owner.data = ohdata;
55*4882a593Smuzhiyun share->s_owner.len = oh->len;
56*4882a593Smuzhiyun share->s_next = file->f_shares;
57*4882a593Smuzhiyun file->f_shares = share;
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun update:
60*4882a593Smuzhiyun share->s_access = argp->fsm_access;
61*4882a593Smuzhiyun share->s_mode = argp->fsm_mode;
62*4882a593Smuzhiyun return nlm_granted;
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun /*
66*4882a593Smuzhiyun * Delete a share.
67*4882a593Smuzhiyun */
68*4882a593Smuzhiyun __be32
nlmsvc_unshare_file(struct nlm_host * host,struct nlm_file * file,struct nlm_args * argp)69*4882a593Smuzhiyun nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,
70*4882a593Smuzhiyun struct nlm_args *argp)
71*4882a593Smuzhiyun {
72*4882a593Smuzhiyun struct nlm_share *share, **shpp;
73*4882a593Smuzhiyun struct xdr_netobj *oh = &argp->lock.oh;
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun for (shpp = &file->f_shares; (share = *shpp) != NULL;
76*4882a593Smuzhiyun shpp = &share->s_next) {
77*4882a593Smuzhiyun if (share->s_host == host && nlm_cmp_owner(share, oh)) {
78*4882a593Smuzhiyun *shpp = share->s_next;
79*4882a593Smuzhiyun kfree(share);
80*4882a593Smuzhiyun return nlm_granted;
81*4882a593Smuzhiyun }
82*4882a593Smuzhiyun }
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun /* X/Open spec says return success even if there was no
85*4882a593Smuzhiyun * corresponding share. */
86*4882a593Smuzhiyun return nlm_granted;
87*4882a593Smuzhiyun }
88*4882a593Smuzhiyun
89*4882a593Smuzhiyun /*
90*4882a593Smuzhiyun * Traverse all shares for a given file, and delete
91*4882a593Smuzhiyun * those owned by the given (type of) host
92*4882a593Smuzhiyun */
nlmsvc_traverse_shares(struct nlm_host * host,struct nlm_file * file,nlm_host_match_fn_t match)93*4882a593Smuzhiyun void nlmsvc_traverse_shares(struct nlm_host *host, struct nlm_file *file,
94*4882a593Smuzhiyun nlm_host_match_fn_t match)
95*4882a593Smuzhiyun {
96*4882a593Smuzhiyun struct nlm_share *share, **shpp;
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun shpp = &file->f_shares;
99*4882a593Smuzhiyun while ((share = *shpp) != NULL) {
100*4882a593Smuzhiyun if (match(share->s_host, host)) {
101*4882a593Smuzhiyun *shpp = share->s_next;
102*4882a593Smuzhiyun kfree(share);
103*4882a593Smuzhiyun continue;
104*4882a593Smuzhiyun }
105*4882a593Smuzhiyun shpp = &share->s_next;
106*4882a593Smuzhiyun }
107*4882a593Smuzhiyun }
108