1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun #include <linux/netlink.h>
3*4882a593Smuzhiyun #include <linux/rtnetlink.h>
4*4882a593Smuzhiyun #include <linux/types.h>
5*4882a593Smuzhiyun #include <net/ip.h>
6*4882a593Smuzhiyun #include <net/net_namespace.h>
7*4882a593Smuzhiyun #include <net/tcp.h>
8*4882a593Smuzhiyun
ip_metrics_convert(struct net * net,struct nlattr * fc_mx,int fc_mx_len,u32 * metrics,struct netlink_ext_ack * extack)9*4882a593Smuzhiyun static int ip_metrics_convert(struct net *net, struct nlattr *fc_mx,
10*4882a593Smuzhiyun int fc_mx_len, u32 *metrics,
11*4882a593Smuzhiyun struct netlink_ext_ack *extack)
12*4882a593Smuzhiyun {
13*4882a593Smuzhiyun bool ecn_ca = false;
14*4882a593Smuzhiyun struct nlattr *nla;
15*4882a593Smuzhiyun int remaining;
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun if (!fc_mx)
18*4882a593Smuzhiyun return 0;
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun nla_for_each_attr(nla, fc_mx, fc_mx_len, remaining) {
21*4882a593Smuzhiyun int type = nla_type(nla);
22*4882a593Smuzhiyun u32 val;
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun if (!type)
25*4882a593Smuzhiyun continue;
26*4882a593Smuzhiyun if (type > RTAX_MAX) {
27*4882a593Smuzhiyun NL_SET_ERR_MSG(extack, "Invalid metric type");
28*4882a593Smuzhiyun return -EINVAL;
29*4882a593Smuzhiyun }
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun if (type == RTAX_CC_ALGO) {
32*4882a593Smuzhiyun char tmp[TCP_CA_NAME_MAX];
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun nla_strlcpy(tmp, nla, sizeof(tmp));
35*4882a593Smuzhiyun val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
36*4882a593Smuzhiyun if (val == TCP_CA_UNSPEC) {
37*4882a593Smuzhiyun NL_SET_ERR_MSG(extack, "Unknown tcp congestion algorithm");
38*4882a593Smuzhiyun return -EINVAL;
39*4882a593Smuzhiyun }
40*4882a593Smuzhiyun } else {
41*4882a593Smuzhiyun if (nla_len(nla) != sizeof(u32)) {
42*4882a593Smuzhiyun NL_SET_ERR_MSG_ATTR(extack, nla,
43*4882a593Smuzhiyun "Invalid attribute in metrics");
44*4882a593Smuzhiyun return -EINVAL;
45*4882a593Smuzhiyun }
46*4882a593Smuzhiyun val = nla_get_u32(nla);
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun if (type == RTAX_ADVMSS && val > 65535 - 40)
49*4882a593Smuzhiyun val = 65535 - 40;
50*4882a593Smuzhiyun if (type == RTAX_MTU && val > 65535 - 15)
51*4882a593Smuzhiyun val = 65535 - 15;
52*4882a593Smuzhiyun if (type == RTAX_HOPLIMIT && val > 255)
53*4882a593Smuzhiyun val = 255;
54*4882a593Smuzhiyun if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK)) {
55*4882a593Smuzhiyun NL_SET_ERR_MSG(extack, "Unknown flag set in feature mask in metrics attribute");
56*4882a593Smuzhiyun return -EINVAL;
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun metrics[type - 1] = val;
59*4882a593Smuzhiyun }
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun if (ecn_ca)
62*4882a593Smuzhiyun metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun return 0;
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun
ip_fib_metrics_init(struct net * net,struct nlattr * fc_mx,int fc_mx_len,struct netlink_ext_ack * extack)67*4882a593Smuzhiyun struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
68*4882a593Smuzhiyun int fc_mx_len,
69*4882a593Smuzhiyun struct netlink_ext_ack *extack)
70*4882a593Smuzhiyun {
71*4882a593Smuzhiyun struct dst_metrics *fib_metrics;
72*4882a593Smuzhiyun int err;
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun if (!fc_mx)
75*4882a593Smuzhiyun return (struct dst_metrics *)&dst_default_metrics;
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun fib_metrics = kzalloc(sizeof(*fib_metrics), GFP_KERNEL);
78*4882a593Smuzhiyun if (unlikely(!fib_metrics))
79*4882a593Smuzhiyun return ERR_PTR(-ENOMEM);
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun err = ip_metrics_convert(net, fc_mx, fc_mx_len, fib_metrics->metrics,
82*4882a593Smuzhiyun extack);
83*4882a593Smuzhiyun if (!err) {
84*4882a593Smuzhiyun refcount_set(&fib_metrics->refcnt, 1);
85*4882a593Smuzhiyun } else {
86*4882a593Smuzhiyun kfree(fib_metrics);
87*4882a593Smuzhiyun fib_metrics = ERR_PTR(err);
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun return fib_metrics;
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(ip_fib_metrics_init);
93