sit: strictly restrict incoming traffic to tunnel link device
Check link device when looking up a tunnel. When a tunnel is
linked to a interface, traffic from a different interface must not
reach the tunnel.
This also allows creating of multiple tunnels with the same
endpoints, if the link device differs.
Signed-off-by: Sascha Hlusiak <contact@saschahlusiak.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index e625041..dfedd56 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -80,7 +80,7 @@
static DEFINE_RWLOCK(ipip6_lock);
static struct ip_tunnel * ipip6_tunnel_lookup(struct net *net,
- __be32 remote, __be32 local)
+ struct net_device *dev, __be32 remote, __be32 local)
{
unsigned h0 = HASH(remote);
unsigned h1 = HASH(local);
@@ -89,18 +89,25 @@
for (t = sitn->tunnels_r_l[h0^h1]; t; t = t->next) {
if (local == t->parms.iph.saddr &&
- remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
+ remote == t->parms.iph.daddr &&
+ (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+ (t->dev->flags & IFF_UP))
return t;
}
for (t = sitn->tunnels_r[h0]; t; t = t->next) {
- if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
+ if (remote == t->parms.iph.daddr &&
+ (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+ (t->dev->flags & IFF_UP))
return t;
}
for (t = sitn->tunnels_l[h1]; t; t = t->next) {
- if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
+ if (local == t->parms.iph.saddr &&
+ (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+ (t->dev->flags & IFF_UP))
return t;
}
- if ((t = sitn->tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
+ t = sitn->tunnels_wc[0];
+ if ((t != NULL) && (t->dev->flags & IFF_UP))
return t;
return NULL;
}
@@ -166,7 +173,8 @@
for (tp = __ipip6_bucket(sitn, parms); (t = *tp) != NULL; tp = &t->next) {
if (local == t->parms.iph.saddr &&
- remote == t->parms.iph.daddr) {
+ remote == t->parms.iph.daddr &&
+ parms->link == t->parms.link) {
if (create)
return NULL;
else
@@ -451,7 +459,10 @@
err = -ENOENT;
read_lock(&ipip6_lock);
- t = ipip6_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
+ t = ipip6_tunnel_lookup(dev_net(skb->dev),
+ skb->dev,
+ iph->daddr,
+ iph->saddr);
if (t == NULL || t->parms.iph.daddr == 0)
goto out;
@@ -486,8 +497,9 @@
iph = ip_hdr(skb);
read_lock(&ipip6_lock);
- if ((tunnel = ipip6_tunnel_lookup(dev_net(skb->dev),
- iph->saddr, iph->daddr)) != NULL) {
+ tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
+ iph->saddr, iph->daddr);
+ if (tunnel != NULL) {
secpath_reset(skb);
skb->mac_header = skb->network_header;
skb_reset_network_header(skb);