diff options
Diffstat (limited to 'net/ipv4/route.c')
| -rw-r--r-- | net/ipv4/route.c | 115 |
1 files changed, 70 insertions, 45 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 95bfa1ba5b28..23bbe29b3bba 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -149,6 +149,7 @@ static void ipv4_dst_destroy(struct dst_entry *dst); static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); static void ipv4_link_failure(struct sk_buff *skb); static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu); +static void ip_do_redirect(struct dst_entry *dst, struct sk_buff *skb); static int rt_garbage_collect(struct dst_ops *ops); static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, @@ -179,6 +180,7 @@ static struct dst_ops ipv4_dst_ops = { .negative_advice = ipv4_negative_advice, .link_failure = ipv4_link_failure, .update_pmtu = ip_rt_update_pmtu, + .redirect = ip_do_redirect, .local_out = __ip_local_out, .neigh_lookup = ipv4_neigh_lookup, }; @@ -1271,16 +1273,35 @@ static void rt_del(unsigned int hash, struct rtable *rt) spin_unlock_bh(rt_hash_lock_addr(hash)); } -/* called in rcu_read_lock() section */ -void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, - __be32 saddr, struct net_device *dev) +static void ip_do_redirect(struct dst_entry *dst, struct sk_buff *skb) { - int s, i; - struct in_device *in_dev = __in_dev_get_rcu(dev); - __be32 skeys[2] = { saddr, 0 }; - int ikeys[2] = { dev->ifindex, 0 }; + const struct iphdr *iph = (const struct iphdr *) skb->data; + __be32 new_gw = icmp_hdr(skb)->un.gateway; + __be32 old_gw = ip_hdr(skb)->saddr; + struct net_device *dev = skb->dev; + __be32 daddr = iph->daddr; + __be32 saddr = iph->saddr; + struct in_device *in_dev; + struct neighbour *n; + struct rtable *rt; struct net *net; + switch (icmp_hdr(skb)->code & 7) { + case ICMP_REDIR_NET: + case ICMP_REDIR_NETTOS: + case ICMP_REDIR_HOST: + case ICMP_REDIR_HOSTTOS: + break; + + default: + return; + } + + rt = (struct rtable *) dst; + if (rt->rt_gateway != old_gw) + return; + + in_dev = __in_dev_get_rcu(dev); if (!in_dev) return; @@ -1300,45 +1321,16 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, goto reject_redirect; } - for (s = 0; s < 2; s++) { - for (i = 0; i < 2; i++) { - unsigned int hash; - struct rtable __rcu **rthp; - struct rtable *rt; - - hash = rt_hash(daddr, skeys[s], ikeys[i], rt_genid(net)); - - rthp = &rt_hash_table[hash].chain; - - while ((rt = rcu_dereference(*rthp)) != NULL) { - struct neighbour *n; - - rthp = &rt->dst.rt_next; - - if (rt->rt_key_dst != daddr || - rt->rt_key_src != skeys[s] || - rt->rt_oif != ikeys[i] || - rt_is_input_route(rt) || - rt_is_expired(rt) || - !net_eq(dev_net(rt->dst.dev), net) || - rt->dst.error || - rt->dst.dev != dev || - rt->rt_gateway != old_gw) - continue; - - n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw); - if (n) { - if (!(n->nud_state & NUD_VALID)) { - neigh_event_send(n, NULL); - } else { - rt->rt_gateway = new_gw; - rt->rt_flags |= RTCF_REDIRECTED; - call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); - } - neigh_release(n); - } - } + n = ipv4_neigh_lookup(dst, NULL, &new_gw); + if (n) { + if (!(n->nud_state & NUD_VALID)) { + neigh_event_send(n, NULL); + } else { + rt->rt_gateway = new_gw; + rt->rt_flags |= RTCF_REDIRECTED; + call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); } + neigh_release(n); } return; @@ -1554,6 +1546,34 @@ void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) } EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu); +void ipv4_redirect(struct sk_buff *skb, struct net *net, + int oif, u32 mark, u8 protocol, int flow_flags) +{ + const struct iphdr *iph = (const struct iphdr *)skb->data; + struct flowi4 fl4; + struct rtable *rt; + + flowi4_init_output(&fl4, oif, mark, RT_TOS(iph->tos), RT_SCOPE_UNIVERSE, + protocol, flow_flags, iph->daddr, iph->saddr, 0, 0); + rt = __ip_route_output_key(net, &fl4); + if (!IS_ERR(rt)) { + ip_do_redirect(&rt->dst, skb); + ip_rt_put(rt); + } +} +EXPORT_SYMBOL_GPL(ipv4_redirect); + +void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk) +{ + const struct inet_sock *inet = inet_sk(sk); + + return ipv4_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, + sk->sk_mark, + inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol, + inet_sk_flowi_flags(sk)); +} +EXPORT_SYMBOL_GPL(ipv4_sk_redirect); + static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) { struct rtable *rt = (struct rtable *) dst; @@ -2571,6 +2591,10 @@ static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu) { } +static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sk_buff *skb) +{ +} + static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst, unsigned long old) { @@ -2585,6 +2609,7 @@ static struct dst_ops ipv4_dst_blackhole_ops = { .mtu = ipv4_blackhole_mtu, .default_advmss = ipv4_default_advmss, .update_pmtu = ipv4_rt_blackhole_update_pmtu, + .redirect = ipv4_rt_blackhole_redirect, .cow_metrics = ipv4_rt_blackhole_cow_metrics, .neigh_lookup = ipv4_neigh_lookup, }; |