Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * common UDP/RAW code | |
4 | * Linux INET implementation | |
5 | * | |
6 | * Authors: | |
7 | * Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> | |
1da177e4 LT |
8 | */ |
9 | ||
1da177e4 LT |
10 | #include <linux/types.h> |
11 | #include <linux/module.h> | |
12 | #include <linux/ip.h> | |
13 | #include <linux/in.h> | |
20380731 | 14 | #include <net/ip.h> |
1da177e4 | 15 | #include <net/sock.h> |
1da177e4 | 16 | #include <net/route.h> |
c752f073 | 17 | #include <net/tcp_states.h> |
acdcecc6 | 18 | #include <net/sock_reuseport.h> |
1da177e4 | 19 | |
03645a11 | 20 | int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) |
1da177e4 LT |
21 | { |
22 | struct inet_sock *inet = inet_sk(sk); | |
23 | struct sockaddr_in *usin = (struct sockaddr_in *) uaddr; | |
3038eeac | 24 | struct flowi4 *fl4; |
1da177e4 | 25 | struct rtable *rt; |
bada8adc | 26 | __be32 saddr; |
1da177e4 LT |
27 | int oif; |
28 | int err; | |
29 | ||
1da177e4 | 30 | |
e905a9ed YH |
31 | if (addr_len < sizeof(*usin)) |
32 | return -EINVAL; | |
33 | ||
34 | if (usin->sin_family != AF_INET) | |
35 | return -EAFNOSUPPORT; | |
1da177e4 LT |
36 | |
37 | sk_dst_reset(sk); | |
38 | ||
39 | oif = sk->sk_bound_dev_if; | |
c720c7e8 | 40 | saddr = inet->inet_saddr; |
f97c1e0c | 41 | if (ipv4_is_multicast(usin->sin_addr.s_addr)) { |
854da991 | 42 | if (!oif || netif_index_is_l3_master(sock_net(sk), oif)) |
1da177e4 LT |
43 | oif = inet->mc_index; |
44 | if (!saddr) | |
45 | saddr = inet->mc_addr; | |
46 | } | |
3038eeac DM |
47 | fl4 = &inet->cork.fl.u.ip4; |
48 | rt = ip_route_connect(fl4, usin->sin_addr.s_addr, saddr, | |
b23dd4fe DM |
49 | RT_CONN_FLAGS(sk), oif, |
50 | sk->sk_protocol, | |
0e0d44ab | 51 | inet->inet_sport, usin->sin_port, sk); |
b23dd4fe DM |
52 | if (IS_ERR(rt)) { |
53 | err = PTR_ERR(rt); | |
584bdf8c | 54 | if (err == -ENETUNREACH) |
c9e90429 | 55 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
3038eeac | 56 | goto out; |
584bdf8c WD |
57 | } |
58 | ||
1da177e4 LT |
59 | if ((rt->rt_flags & RTCF_BROADCAST) && !sock_flag(sk, SOCK_BROADCAST)) { |
60 | ip_rt_put(rt); | |
3038eeac DM |
61 | err = -EACCES; |
62 | goto out; | |
1da177e4 | 63 | } |
c720c7e8 | 64 | if (!inet->inet_saddr) |
3038eeac | 65 | inet->inet_saddr = fl4->saddr; /* Update source address */ |
719f8358 | 66 | if (!inet->inet_rcv_saddr) { |
3038eeac | 67 | inet->inet_rcv_saddr = fl4->saddr; |
719f8358 ED |
68 | if (sk->sk_prot->rehash) |
69 | sk->sk_prot->rehash(sk); | |
70 | } | |
3038eeac | 71 | inet->inet_daddr = fl4->daddr; |
c720c7e8 | 72 | inet->inet_dport = usin->sin_port; |
acdcecc6 | 73 | reuseport_has_conns(sk, true); |
1da177e4 | 74 | sk->sk_state = TCP_ESTABLISHED; |
877d1f62 | 75 | sk_set_txhash(sk); |
a904a069 | 76 | inet->inet_id = prandom_u32(); |
1da177e4 | 77 | |
d8d1f30b | 78 | sk_dst_set(sk, &rt->dst); |
3038eeac DM |
79 | err = 0; |
80 | out: | |
3038eeac | 81 | return err; |
1da177e4 | 82 | } |
03645a11 ED |
83 | EXPORT_SYMBOL(__ip4_datagram_connect); |
84 | ||
85 | int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
86 | { | |
87 | int res; | |
88 | ||
89 | lock_sock(sk); | |
90 | res = __ip4_datagram_connect(sk, uaddr, addr_len); | |
91 | release_sock(sk); | |
92 | return res; | |
93 | } | |
1da177e4 | 94 | EXPORT_SYMBOL(ip4_datagram_connect); |
8141ed9f | 95 | |
9709674e ED |
96 | /* Because UDP xmit path can manipulate sk_dst_cache without holding |
97 | * socket lock, we need to use sk_dst_set() here, | |
98 | * even if we own the socket lock. | |
99 | */ | |
8141ed9f SK |
100 | void ip4_datagram_release_cb(struct sock *sk) |
101 | { | |
102 | const struct inet_sock *inet = inet_sk(sk); | |
103 | const struct ip_options_rcu *inet_opt; | |
104 | __be32 daddr = inet->inet_daddr; | |
9709674e | 105 | struct dst_entry *dst; |
8141ed9f SK |
106 | struct flowi4 fl4; |
107 | struct rtable *rt; | |
108 | ||
8141ed9f | 109 | rcu_read_lock(); |
9709674e ED |
110 | |
111 | dst = __sk_dst_get(sk); | |
112 | if (!dst || !dst->obsolete || dst->ops->check(dst, 0)) { | |
113 | rcu_read_unlock(); | |
114 | return; | |
115 | } | |
8141ed9f SK |
116 | inet_opt = rcu_dereference(inet->inet_opt); |
117 | if (inet_opt && inet_opt->opt.srr) | |
118 | daddr = inet_opt->opt.faddr; | |
119 | rt = ip_route_output_ports(sock_net(sk), &fl4, sk, daddr, | |
120 | inet->inet_saddr, inet->inet_dport, | |
121 | inet->inet_sport, sk->sk_protocol, | |
122 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if); | |
9709674e ED |
123 | |
124 | dst = !IS_ERR(rt) ? &rt->dst : NULL; | |
125 | sk_dst_set(sk, dst); | |
126 | ||
8141ed9f SK |
127 | rcu_read_unlock(); |
128 | } | |
129 | EXPORT_SYMBOL_GPL(ip4_datagram_release_cb); |