root/net/ipv4/datagram.c

DEFINITIONS

1. ip4_datagram_connect

/*
 *      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 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);

        oif = sk->sk_bound_dev_if;
        saddr = inet->saddr;
        if (ipv4_is_multicast(usin->sin_addr.s_addr)) {
                if (!oif)
                        oif = inet->mc_index;
                if (!saddr)
                        saddr = inet->mc_addr;
        }
        err = ip_route_connect(&rt, usin->sin_addr.s_addr, saddr,
                               RT_CONN_FLAGS(sk), oif,
                               sk->sk_protocol,
                               inet->sport, usin->sin_port, sk, 1);
        if (err) {
                if (err == -ENETUNREACH)
                        IP_INC_STATS_BH(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
                return err;
        }

        if ((rt->rt_flags & RTCF_BROADCAST) && !sock_flag(sk, SOCK_BROADCAST)) {
                ip_rt_put(rt);
                return -EACCES;
        }
        if (!inet->saddr)
                inet->saddr = rt->rt_src;       /* Update source address */
        if (!inet->rcv_saddr)
                inet->rcv_saddr = rt->rt_src;
        inet->daddr = rt->rt_dst;
        inet->dport = usin->sin_port;
        sk->sk_state = TCP_ESTABLISHED;
        inet->id = jiffies;

        sk_dst_set(sk, &rt->u.dst);
        return(0);
}

EXPORT_SYMBOL(ip4_datagram_connect);