3 * Linux INET implementation
6 * Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
14 #include <linux/types.h>
15 #include <linux/module.h>
20 #include <net/route.h>
21 #include <net/tcp_states.h>
23 int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
25 struct inet_sock *inet = inet_sk(sk);
26 struct sockaddr_in *usin = (struct sockaddr_in *) uaddr;
34 if (addr_len < sizeof(*usin))
37 if (usin->sin_family != AF_INET)
44 oif = sk->sk_bound_dev_if;
45 saddr = inet->inet_saddr;
46 if (ipv4_is_multicast(usin->sin_addr.s_addr)) {
50 saddr = inet->mc_addr;
52 fl4 = &inet->cork.fl.u.ip4;
53 rt = ip_route_connect(fl4, usin->sin_addr.s_addr, saddr,
54 RT_CONN_FLAGS(sk), oif,
56 inet->inet_sport, usin->sin_port, sk);
59 if (err == -ENETUNREACH)
60 IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
64 if ((rt->rt_flags & RTCF_BROADCAST) && !sock_flag(sk, SOCK_BROADCAST)) {
69 if (!inet->inet_saddr)
70 inet->inet_saddr = fl4->saddr; /* Update source address */
71 if (!inet->inet_rcv_saddr) {
72 inet->inet_rcv_saddr = fl4->saddr;
73 if (sk->sk_prot->rehash)
74 sk->sk_prot->rehash(sk);
76 inet->inet_daddr = fl4->daddr;
77 inet->inet_dport = usin->sin_port;
78 sk->sk_state = TCP_ESTABLISHED;
80 inet->inet_id = jiffies;
82 sk_dst_set(sk, &rt->dst);
88 EXPORT_SYMBOL(ip4_datagram_connect);
90 /* Because UDP xmit path can manipulate sk_dst_cache without holding
91 * socket lock, we need to use sk_dst_set() here,
92 * even if we own the socket lock.
94 void ip4_datagram_release_cb(struct sock *sk)
96 const struct inet_sock *inet = inet_sk(sk);
97 const struct ip_options_rcu *inet_opt;
98 __be32 daddr = inet->inet_daddr;
99 struct dst_entry *dst;
105 dst = __sk_dst_get(sk);
106 if (!dst || !dst->obsolete || dst->ops->check(dst, 0)) {
110 inet_opt = rcu_dereference(inet->inet_opt);
111 if (inet_opt && inet_opt->opt.srr)
112 daddr = inet_opt->opt.faddr;
113 rt = ip_route_output_ports(sock_net(sk), &fl4, sk, daddr,
114 inet->inet_saddr, inet->inet_dport,
115 inet->inet_sport, sk->sk_protocol,
116 RT_CONN_FLAGS(sk), sk->sk_bound_dev_if);
118 dst = !IS_ERR(rt) ? &rt->dst : NULL;
123 EXPORT_SYMBOL_GPL(ip4_datagram_release_cb);