gre: strict physical device binding
Check the device on receive path and allow otherwise identical devices
as long as the physical device differs.
This is useful for NBMA tunnels, where you want to use different gre IP
for each public IP available via different physical devices.
Signed-off-by: Timo Teras <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 0101521..4a43739 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -164,67 +164,113 @@
/* Given src, dst and key, find appropriate for input tunnel. */
-static struct ip_tunnel * ipgre_tunnel_lookup(struct net *net,
+static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev,
__be32 remote, __be32 local,
__be32 key, __be16 gre_proto)
{
+ struct net *net = dev_net(dev);
+ int link = dev->ifindex;
unsigned h0 = HASH(remote);
unsigned h1 = HASH(key);
- struct ip_tunnel *t;
- struct ip_tunnel *t2 = NULL;
+ struct ip_tunnel *t, *sel[4] = { NULL, NULL, NULL, NULL };
struct ipgre_net *ign = net_generic(net, ipgre_net_id);
int dev_type = (gre_proto == htons(ETH_P_TEB)) ?
ARPHRD_ETHER : ARPHRD_IPGRE;
+ int idx;
for (t = ign->tunnels_r_l[h0^h1]; t; t = t->next) {
- if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) {
- if (t->parms.i_key == key && t->dev->flags & IFF_UP) {
- if (t->dev->type == dev_type)
- return t;
- if (t->dev->type == ARPHRD_IPGRE && !t2)
- t2 = t;
- }
- }
+ if (local != t->parms.iph.saddr ||
+ remote != t->parms.iph.daddr ||
+ key != t->parms.i_key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->dev->type != ARPHRD_IPGRE &&
+ t->dev->type != dev_type)
+ continue;
+
+ idx = 0;
+ if (t->parms.link != link)
+ idx |= 1;
+ if (t->dev->type != dev_type)
+ idx |= 2;
+ if (idx == 0)
+ return t;
+ if (sel[idx] == NULL)
+ sel[idx] = t;
}
for (t = ign->tunnels_r[h0^h1]; t; t = t->next) {
- if (remote == t->parms.iph.daddr) {
- if (t->parms.i_key == key && t->dev->flags & IFF_UP) {
- if (t->dev->type == dev_type)
- return t;
- if (t->dev->type == ARPHRD_IPGRE && !t2)
- t2 = t;
- }
- }
+ if (remote != t->parms.iph.daddr ||
+ key != t->parms.i_key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->dev->type != ARPHRD_IPGRE &&
+ t->dev->type != dev_type)
+ continue;
+
+ idx = 0;
+ if (t->parms.link != link)
+ idx |= 1;
+ if (t->dev->type != dev_type)
+ idx |= 2;
+ if (idx == 0)
+ return t;
+ if (sel[idx] == NULL)
+ sel[idx] = t;
}
for (t = ign->tunnels_l[h1]; t; t = t->next) {
- if (local == t->parms.iph.saddr ||
- (local == t->parms.iph.daddr &&
- ipv4_is_multicast(local))) {
- if (t->parms.i_key == key && t->dev->flags & IFF_UP) {
- if (t->dev->type == dev_type)
- return t;
- if (t->dev->type == ARPHRD_IPGRE && !t2)
- t2 = t;
- }
- }
+ if ((local != t->parms.iph.saddr &&
+ (local != t->parms.iph.daddr ||
+ !ipv4_is_multicast(local))) ||
+ key != t->parms.i_key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->dev->type != ARPHRD_IPGRE &&
+ t->dev->type != dev_type)
+ continue;
+
+ idx = 0;
+ if (t->parms.link != link)
+ idx |= 1;
+ if (t->dev->type != dev_type)
+ idx |= 2;
+ if (idx == 0)
+ return t;
+ if (sel[idx] == NULL)
+ sel[idx] = t;
}
for (t = ign->tunnels_wc[h1]; t; t = t->next) {
- if (t->parms.i_key == key && t->dev->flags & IFF_UP) {
- if (t->dev->type == dev_type)
- return t;
- if (t->dev->type == ARPHRD_IPGRE && !t2)
- t2 = t;
- }
+ if (t->parms.i_key != key ||
+ !(t->dev->flags & IFF_UP))
+ continue;
+
+ if (t->dev->type != ARPHRD_IPGRE &&
+ t->dev->type != dev_type)
+ continue;
+
+ idx = 0;
+ if (t->parms.link != link)
+ idx |= 1;
+ if (t->dev->type != dev_type)
+ idx |= 2;
+ if (idx == 0)
+ return t;
+ if (sel[idx] == NULL)
+ sel[idx] = t;
}
- if (t2)
- return t2;
+ for (idx = 1; idx < ARRAY_SIZE(sel); idx++)
+ if (sel[idx] != NULL)
+ return sel[idx];
- if (ign->fb_tunnel_dev->flags&IFF_UP)
+ if (ign->fb_tunnel_dev->flags & IFF_UP)
return netdev_priv(ign->fb_tunnel_dev);
+
return NULL;
}
@@ -284,6 +330,7 @@
__be32 remote = parms->iph.daddr;
__be32 local = parms->iph.saddr;
__be32 key = parms->i_key;
+ int link = parms->link;
struct ip_tunnel *t, **tp;
struct ipgre_net *ign = net_generic(net, ipgre_net_id);
@@ -291,6 +338,7 @@
if (local == t->parms.iph.saddr &&
remote == t->parms.iph.daddr &&
key == t->parms.i_key &&
+ link == t->parms.link &&
type == t->dev->type)
break;
@@ -421,7 +469,7 @@
}
read_lock(&ipgre_lock);
- t = ipgre_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr,
+ t = ipgre_tunnel_lookup(skb->dev, iph->daddr, iph->saddr,
flags & GRE_KEY ?
*(((__be32 *)p) + (grehlen / 4) - 1) : 0,
p[1]);
@@ -518,7 +566,7 @@
gre_proto = *(__be16 *)(h + 2);
read_lock(&ipgre_lock);
- if ((tunnel = ipgre_tunnel_lookup(dev_net(skb->dev),
+ if ((tunnel = ipgre_tunnel_lookup(skb->dev,
iph->saddr, iph->daddr, key,
gre_proto))) {
struct net_device_stats *stats = &tunnel->dev->stats;