ipv4: Add a socket release callback for datagram sockets

This implements a socket release callback function to check
if the socket cached route got invalid during the time
we owned the socket. The function is used from udp, raw
and ping sockets.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Steffen Klassert 2013-01-21 02:00:03 +00:00 committed by David S. Miller
parent 9cb3a50c5f
commit 8141ed9fce
5 changed files with 30 additions and 0 deletions

View file

@ -143,6 +143,8 @@ static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
extern int ip4_datagram_connect(struct sock *sk,
struct sockaddr *uaddr, int addr_len);
extern void ip4_datagram_release_cb(struct sock *sk);
struct ip_reply_arg {
struct kvec iov[1];
int flags;

View file

@ -85,3 +85,28 @@ int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
return err;
}
EXPORT_SYMBOL(ip4_datagram_connect);
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 flowi4 fl4;
struct rtable *rt;
if (! __sk_dst_get(sk) || __sk_dst_check(sk, 0))
return;
rcu_read_lock();
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);
if (!IS_ERR(rt))
__sk_dst_set(sk, &rt->dst);
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(ip4_datagram_release_cb);

View file

@ -738,6 +738,7 @@ struct proto ping_prot = {
.recvmsg = ping_recvmsg,
.bind = ping_bind,
.backlog_rcv = ping_queue_rcv_skb,
.release_cb = ip4_datagram_release_cb,
.hash = ping_v4_hash,
.unhash = ping_v4_unhash,
.get_port = ping_v4_get_port,

View file

@ -894,6 +894,7 @@ struct proto raw_prot = {
.recvmsg = raw_recvmsg,
.bind = raw_bind,
.backlog_rcv = raw_rcv_skb,
.release_cb = ip4_datagram_release_cb,
.hash = raw_hash_sk,
.unhash = raw_unhash_sk,
.obj_size = sizeof(struct raw_sock),

View file

@ -1952,6 +1952,7 @@ struct proto udp_prot = {
.recvmsg = udp_recvmsg,
.sendpage = udp_sendpage,
.backlog_rcv = __udp_queue_rcv_skb,
.release_cb = ip4_datagram_release_cb,
.hash = udp_lib_hash,
.unhash = udp_lib_unhash,
.rehash = udp_v4_rehash,