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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/ipv4/datagram.c
Initial import
Diffstat (limited to 'net/ipv4/datagram.c')
-rw-r--r--net/ipv4/datagram.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/net/ipv4/datagram.c b/net/ipv4/datagram.c
new file mode 100644
index 000000000..90c0e8386
--- /dev/null
+++ b/net/ipv4/datagram.c
@@ -0,0 +1,123 @@
+/*
+ * common UDP/RAW code
+ * Linux INET implementation
+ *
+ * Authors:
+ * Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/ip.h>
+#include <linux/in.h>
+#include <net/ip.h>
+#include <net/sock.h>
+#include <net/route.h>
+#include <net/tcp_states.h>
+
+int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
+{
+ struct inet_sock *inet = inet_sk(sk);
+ struct sockaddr_in *usin = (struct sockaddr_in *) uaddr;
+ struct flowi4 *fl4;
+ struct rtable *rt;
+ __be32 saddr;
+ int oif;
+ int err;
+
+
+ if (addr_len < sizeof(*usin))
+ return -EINVAL;
+
+ if (usin->sin_family != AF_INET)
+ return -EAFNOSUPPORT;
+
+ sk_dst_reset(sk);
+
+ lock_sock(sk);
+
+ oif = sk->sk_bound_dev_if;
+ saddr = inet->inet_saddr;
+ if (ipv4_is_multicast(usin->sin_addr.s_addr)) {
+ if (!oif)
+ oif = inet->mc_index;
+ if (!saddr)
+ saddr = inet->mc_addr;
+ }
+ fl4 = &inet->cork.fl.u.ip4;
+ rt = ip_route_connect(fl4, usin->sin_addr.s_addr, saddr,
+ RT_CONN_FLAGS(sk), oif,
+ sk->sk_protocol,
+ inet->inet_sport, usin->sin_port, sk);
+ if (IS_ERR(rt)) {
+ err = PTR_ERR(rt);
+ if (err == -ENETUNREACH)
+ IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
+ goto out;
+ }
+
+ if ((rt->rt_flags & RTCF_BROADCAST) && !sock_flag(sk, SOCK_BROADCAST)) {
+ ip_rt_put(rt);
+ err = -EACCES;
+ goto out;
+ }
+ if (!inet->inet_saddr)
+ inet->inet_saddr = fl4->saddr; /* Update source address */
+ if (!inet->inet_rcv_saddr) {
+ inet->inet_rcv_saddr = fl4->saddr;
+ if (sk->sk_prot->rehash)
+ sk->sk_prot->rehash(sk);
+ }
+ inet->inet_daddr = fl4->daddr;
+ inet->inet_dport = usin->sin_port;
+ sk->sk_state = TCP_ESTABLISHED;
+ inet_set_txhash(sk);
+ inet->inet_id = jiffies;
+
+ sk_dst_set(sk, &rt->dst);
+ err = 0;
+out:
+ release_sock(sk);
+ return err;
+}
+EXPORT_SYMBOL(ip4_datagram_connect);
+
+/* Because UDP xmit path can manipulate sk_dst_cache without holding
+ * socket lock, we need to use sk_dst_set() here,
+ * even if we own the socket lock.
+ */
+void ip4_datagram_release_cb(struct sock *sk)
+{
+ const struct inet_sock *inet = inet_sk(sk);
+ const struct ip_options_rcu *inet_opt;
+ __be32 daddr = inet->inet_daddr;
+ struct dst_entry *dst;
+ struct flowi4 fl4;
+ struct rtable *rt;
+
+ rcu_read_lock();
+
+ dst = __sk_dst_get(sk);
+ if (!dst || !dst->obsolete || dst->ops->check(dst, 0)) {
+ rcu_read_unlock();
+ return;
+ }
+ inet_opt = rcu_dereference(inet->inet_opt);
+ if (inet_opt && inet_opt->opt.srr)
+ daddr = inet_opt->opt.faddr;
+ rt = ip_route_output_ports(sock_net(sk), &fl4, sk, daddr,
+ inet->inet_saddr, inet->inet_dport,
+ inet->inet_sport, sk->sk_protocol,
+ RT_CONN_FLAGS(sk), sk->sk_bound_dev_if);
+
+ dst = !IS_ERR(rt) ? &rt->dst : NULL;
+ sk_dst_set(sk, dst);
+
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(ip4_datagram_release_cb);