130 lines
3.1 KiB
C
130 lines
3.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* common UDP/RAW code
|
|
* Linux INET implementation
|
|
*
|
|
* Authors:
|
|
* Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/module.h>
|
|
#include <linux/in.h>
|
|
#include <net/ip.h>
|
|
#include <net/sock.h>
|
|
#include <net/route.h>
|
|
#include <net/tcp_states.h>
|
|
#include <net/sock_reuseport.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);
|
|
|
|
oif = sk->sk_bound_dev_if;
|
|
saddr = inet->inet_saddr;
|
|
if (ipv4_is_multicast(usin->sin_addr.s_addr)) {
|
|
if (!oif || netif_index_is_l3_master(sock_net(sk), oif))
|
|
oif = inet->mc_index;
|
|
if (!saddr)
|
|
saddr = inet->mc_addr;
|
|
} else if (!oif) {
|
|
oif = inet->uc_index;
|
|
}
|
|
fl4 = &inet->cork.fl.u.ip4;
|
|
rt = ip_route_connect(fl4, usin->sin_addr.s_addr, saddr, 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;
|
|
reuseport_has_conns_set(sk);
|
|
sk->sk_state = TCP_ESTABLISHED;
|
|
sk_set_txhash(sk);
|
|
inet->inet_id = get_random_u16();
|
|
|
|
sk_dst_set(sk, &rt->dst);
|
|
err = 0;
|
|
out:
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(__ip4_datagram_connect);
|
|
|
|
int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
|
|
{
|
|
int res;
|
|
|
|
lock_sock(sk);
|
|
res = __ip4_datagram_connect(sk, uaddr, addr_len);
|
|
release_sock(sk);
|
|
return res;
|
|
}
|
|
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);
|