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-rw-r--r--net/ipv4/ah4.c18
-rw-r--r--net/ipv4/esp4.c18
-rw-r--r--net/ipv4/icmp.c74
-rw-r--r--net/ipv4/ip_gre.c9
-rw-r--r--net/ipv4/ipcomp.c18
-rw-r--r--net/ipv4/ipip.c9
-rw-r--r--net/ipv4/ping.c1
-rw-r--r--net/ipv4/raw.c2
-rw-r--r--net/ipv4/route.c115
-rw-r--r--net/ipv4/tcp_ipv4.c11
-rw-r--r--net/ipv4/udp.c3
-rw-r--r--net/ipv4/xfrm4_policy.c9
12 files changed, 174 insertions, 113 deletions
diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c
index 916d5ecaf6c6..a0d8392491c3 100644
--- a/net/ipv4/ah4.c
+++ b/net/ipv4/ah4.c
@@ -398,17 +398,25 @@ static void ah4_err(struct sk_buff *skb, u32 info)
struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
struct xfrm_state *x;
- if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH ||
- icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
+ switch (icmp_hdr(skb)->type) {
+ case ICMP_DEST_UNREACH:
+ if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
+ return;
+ case ICMP_REDIRECT:
+ break;
+ default:
return;
+ }
x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
ah->spi, IPPROTO_AH, AF_INET);
if (!x)
return;
- pr_debug("pmtu discovery on SA AH/%08x/%08x\n",
- ntohl(ah->spi), ntohl(iph->daddr));
- ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_AH, 0);
+
+ if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
+ ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_AH, 0);
+ else
+ ipv4_redirect(skb, net, 0, 0, IPPROTO_AH, 0);
xfrm_state_put(x);
}
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 7b95b49a36ce..b61e9deb7c7e 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -484,17 +484,25 @@ static void esp4_err(struct sk_buff *skb, u32 info)
struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
struct xfrm_state *x;
- if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH ||
- icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
+ switch (icmp_hdr(skb)->type) {
+ case ICMP_DEST_UNREACH:
+ if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
+ return;
+ case ICMP_REDIRECT:
+ break;
+ default:
return;
+ }
x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
esph->spi, IPPROTO_ESP, AF_INET);
if (!x)
return;
- NETDEBUG(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%08x\n",
- ntohl(esph->spi), ntohl(iph->daddr));
- ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0);
+
+ if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
+ ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0);
+ else
+ ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0);
xfrm_state_put(x);
}
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 4a049449305f..d01aeb4d492e 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -634,18 +634,31 @@ out:;
EXPORT_SYMBOL(icmp_send);
+static void icmp_socket_deliver(struct sk_buff *skb, u32 info)
+{
+ const struct iphdr *iph = (const struct iphdr *) skb->data;
+ const struct net_protocol *ipprot;
+ int protocol = iph->protocol;
+
+ raw_icmp_error(skb, protocol, info);
+
+ rcu_read_lock();
+ ipprot = rcu_dereference(inet_protos[protocol]);
+ if (ipprot && ipprot->err_handler)
+ ipprot->err_handler(skb, info);
+ rcu_read_unlock();
+}
+
/*
* Handle ICMP_DEST_UNREACH, ICMP_TIME_EXCEED, and ICMP_QUENCH.
*/
static void icmp_unreach(struct sk_buff *skb)
{
- const struct net_protocol *ipprot;
const struct iphdr *iph;
struct icmphdr *icmph;
struct net *net;
u32 info = 0;
- int protocol;
net = dev_net(skb_dst(skb)->dev);
@@ -726,19 +739,7 @@ static void icmp_unreach(struct sk_buff *skb)
if (!pskb_may_pull(skb, iph->ihl * 4 + 8))
goto out;
- iph = (const struct iphdr *)skb->data;
- protocol = iph->protocol;
-
- /*
- * Deliver ICMP message to raw sockets. Pretty useless feature?
- */
- raw_icmp_error(skb, protocol, info);
-
- rcu_read_lock();
- ipprot = rcu_dereference(inet_protos[protocol]);
- if (ipprot && ipprot->err_handler)
- ipprot->err_handler(skb, info);
- rcu_read_unlock();
+ icmp_socket_deliver(skb, info);
out:
return;
@@ -754,46 +755,15 @@ out_err:
static void icmp_redirect(struct sk_buff *skb)
{
- const struct iphdr *iph;
-
- if (skb->len < sizeof(struct iphdr))
- goto out_err;
-
- /*
- * Get the copied header of the packet that caused the redirect
- */
- if (!pskb_may_pull(skb, sizeof(struct iphdr)))
- goto out;
-
- iph = (const struct iphdr *)skb->data;
-
- switch (icmp_hdr(skb)->code & 7) {
- case ICMP_REDIR_NET:
- case ICMP_REDIR_NETTOS:
- /*
- * As per RFC recommendations now handle it as a host redirect.
- */
- case ICMP_REDIR_HOST:
- case ICMP_REDIR_HOSTTOS:
- ip_rt_redirect(ip_hdr(skb)->saddr, iph->daddr,
- icmp_hdr(skb)->un.gateway,
- iph->saddr, skb->dev);
- break;
+ if (skb->len < sizeof(struct iphdr)) {
+ ICMP_INC_STATS_BH(dev_net(skb->dev), ICMP_MIB_INERRORS);
+ return;
}
- /* Ping wants to see redirects.
- * Let's pretend they are errors of sorts... */
- if (iph->protocol == IPPROTO_ICMP &&
- iph->ihl >= 5 &&
- pskb_may_pull(skb, (iph->ihl<<2)+8)) {
- ping_err(skb, icmp_hdr(skb)->un.gateway);
- }
+ if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+ return;
-out:
- return;
-out_err:
- ICMP_INC_STATS_BH(dev_net(skb->dev), ICMP_MIB_INERRORS);
- goto out;
+ icmp_socket_deliver(skb, icmp_hdr(skb)->un.gateway);
}
/*
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 594cec35ac4d..0c3123566d76 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -528,6 +528,9 @@ static void ipgre_err(struct sk_buff *skb, u32 info)
if (code != ICMP_EXC_TTL)
return;
break;
+
+ case ICMP_REDIRECT:
+ break;
}
rcu_read_lock();
@@ -543,7 +546,11 @@ static void ipgre_err(struct sk_buff *skb, u32 info)
t->parms.link, 0, IPPROTO_GRE, 0);
goto out;
}
-
+ if (type == ICMP_REDIRECT) {
+ ipv4_redirect(skb, dev_net(skb->dev), t->parms.link, 0,
+ IPPROTO_GRE, 0);
+ goto out;
+ }
if (t->parms.iph.daddr == 0 ||
ipv4_is_multicast(t->parms.iph.daddr))
goto out;
diff --git a/net/ipv4/ipcomp.c b/net/ipv4/ipcomp.c
index b91375482d84..d3ab47e19a89 100644
--- a/net/ipv4/ipcomp.c
+++ b/net/ipv4/ipcomp.c
@@ -31,18 +31,26 @@ static void ipcomp4_err(struct sk_buff *skb, u32 info)
struct ip_comp_hdr *ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
struct xfrm_state *x;
- if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH ||
- icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
+ switch (icmp_hdr(skb)->type) {
+ case ICMP_DEST_UNREACH:
+ if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
+ return;
+ case ICMP_REDIRECT:
+ break;
+ default:
return;
+ }
spi = htonl(ntohs(ipch->cpi));
x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
spi, IPPROTO_COMP, AF_INET);
if (!x)
return;
- NETDEBUG(KERN_DEBUG "pmtu discovery on SA IPCOMP/%08x/%pI4\n",
- spi, &iph->daddr);
- ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_COMP, 0);
+
+ if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
+ ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_COMP, 0);
+ else
+ ipv4_redirect(skb, net, 0, 0, IPPROTO_COMP, 0);
xfrm_state_put(x);
}
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 715338a1b205..c2d0e6d8baaf 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -360,6 +360,8 @@ static int ipip_err(struct sk_buff *skb, u32 info)
if (code != ICMP_EXC_TTL)
return 0;
break;
+ case ICMP_REDIRECT:
+ break;
}
err = -ENOENT;
@@ -376,6 +378,13 @@ static int ipip_err(struct sk_buff *skb, u32 info)
goto out;
}
+ if (type == ICMP_REDIRECT) {
+ ipv4_redirect(skb, dev_net(skb->dev), t->dev->ifindex, 0,
+ IPPROTO_IPIP, 0);
+ err = 0;
+ goto out;
+ }
+
if (t->parms.iph.daddr == 0)
goto out;
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 340fcf29a966..6232d476f37e 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -387,6 +387,7 @@ void ping_err(struct sk_buff *skb, u32 info)
break;
case ICMP_REDIRECT:
/* See ICMP_SOURCE_QUENCH */
+ ipv4_sk_redirect(skb, sk);
err = EREMOTEIO;
break;
}
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 659ddfb10947..ff0f071969ea 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -218,6 +218,8 @@ static void raw_err(struct sock *sk, struct sk_buff *skb, u32 info)
if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)
ipv4_sk_update_pmtu(skb, sk, info);
+ else if (type == ICMP_REDIRECT)
+ ipv4_sk_redirect(skb, sk);
/* Report error on raw socket, if:
1. User requested ip_recverr.
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,
};
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 01545a3fc0f2..7a0062cb4ed0 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -321,6 +321,14 @@ static void do_pmtu_discovery(struct sock *sk, const struct iphdr *iph, u32 mtu)
} /* else let the usual retransmit timer handle it */
}
+static void do_redirect(struct sk_buff *skb, struct sock *sk)
+{
+ struct dst_entry *dst = __sk_dst_check(sk, 0);
+
+ if (dst)
+ dst->ops->redirect(dst, skb);
+}
+
/*
* This routine is called by the ICMP module when it gets some
* sort of error condition. If err < 0 then the socket should
@@ -394,6 +402,9 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
}
switch (type) {
+ case ICMP_REDIRECT:
+ do_redirect(icmp_skb, sk);
+ goto out;
case ICMP_SOURCE_QUENCH:
/* Just silently ignore these. */
goto out;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index ee37d47d472e..b4c3582a991f 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -630,6 +630,9 @@ void __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
err = icmp_err_convert[code].errno;
}
break;
+ case ICMP_REDIRECT:
+ ipv4_sk_redirect(skb, sk);
+ break;
}
/*
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 87d3fcc302d4..737131cef375 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -202,6 +202,14 @@ static void xfrm4_update_pmtu(struct dst_entry *dst, u32 mtu)
path->ops->update_pmtu(path, mtu);
}
+static void xfrm4_redirect(struct dst_entry *dst, struct sk_buff *skb)
+{
+ struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+ struct dst_entry *path = xdst->route;
+
+ path->ops->redirect(path, skb);
+}
+
static void xfrm4_dst_destroy(struct dst_entry *dst)
{
struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
@@ -225,6 +233,7 @@ static struct dst_ops xfrm4_dst_ops = {
.protocol = cpu_to_be16(ETH_P_IP),
.gc = xfrm4_garbage_collect,
.update_pmtu = xfrm4_update_pmtu,
+ .redirect = xfrm4_redirect,
.cow_metrics = dst_cow_metrics_generic,
.destroy = xfrm4_dst_destroy,
.ifdown = xfrm4_dst_ifdown,
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.