Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[linux-2.6-microblaze.git] / net / ipv4 / metrics.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/netlink.h>
3 #include <linux/rtnetlink.h>
4 #include <linux/types.h>
5 #include <net/ip.h>
6 #include <net/net_namespace.h>
7 #include <net/tcp.h>
8
9 static int ip_metrics_convert(struct net *net, struct nlattr *fc_mx,
10                               int fc_mx_len, u32 *metrics,
11                               struct netlink_ext_ack *extack)
12 {
13         bool ecn_ca = false;
14         struct nlattr *nla;
15         int remaining;
16
17         if (!fc_mx)
18                 return 0;
19
20         nla_for_each_attr(nla, fc_mx, fc_mx_len, remaining) {
21                 int type = nla_type(nla);
22                 u32 val;
23
24                 if (!type)
25                         continue;
26                 if (type > RTAX_MAX) {
27                         NL_SET_ERR_MSG(extack, "Invalid metric type");
28                         return -EINVAL;
29                 }
30
31                 if (type == RTAX_CC_ALGO) {
32                         char tmp[TCP_CA_NAME_MAX];
33
34                         nla_strscpy(tmp, nla, sizeof(tmp));
35                         val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
36                         if (val == TCP_CA_UNSPEC) {
37                                 NL_SET_ERR_MSG(extack, "Unknown tcp congestion algorithm");
38                                 return -EINVAL;
39                         }
40                 } else {
41                         if (nla_len(nla) != sizeof(u32)) {
42                                 NL_SET_ERR_MSG_ATTR(extack, nla,
43                                                     "Invalid attribute in metrics");
44                                 return -EINVAL;
45                         }
46                         val = nla_get_u32(nla);
47                 }
48                 if (type == RTAX_ADVMSS && val > 65535 - 40)
49                         val = 65535 - 40;
50                 if (type == RTAX_MTU && val > 65535 - 15)
51                         val = 65535 - 15;
52                 if (type == RTAX_HOPLIMIT && val > 255)
53                         val = 255;
54                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK)) {
55                         NL_SET_ERR_MSG(extack, "Unknown flag set in feature mask in metrics attribute");
56                         return -EINVAL;
57                 }
58                 metrics[type - 1] = val;
59         }
60
61         if (ecn_ca)
62                 metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
63
64         return 0;
65 }
66
67 struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
68                                         int fc_mx_len,
69                                         struct netlink_ext_ack *extack)
70 {
71         struct dst_metrics *fib_metrics;
72         int err;
73
74         if (!fc_mx)
75                 return (struct dst_metrics *)&dst_default_metrics;
76
77         fib_metrics = kzalloc(sizeof(*fib_metrics), GFP_KERNEL);
78         if (unlikely(!fib_metrics))
79                 return ERR_PTR(-ENOMEM);
80
81         err = ip_metrics_convert(net, fc_mx, fc_mx_len, fib_metrics->metrics,
82                                  extack);
83         if (!err) {
84                 refcount_set(&fib_metrics->refcnt, 1);
85         } else {
86                 kfree(fib_metrics);
87                 fib_metrics = ERR_PTR(err);
88         }
89
90         return fib_metrics;
91 }
92 EXPORT_SYMBOL_GPL(ip_fib_metrics_init);