diff mbox

gre: strict physical device binding

Message ID 1232609084-566-1-git-send-email-timo.teras@iki.fi
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Timo Teras Jan. 22, 2009, 7:24 a.m. UTC 
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>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
---
Updated as requested. Compile tested.
Sent as new patch since I haven't seen the earlier patch pushed yet.

 net/ipv4/ip_gre.c |  131 ++++++++++++++++++++++++++++++++++++++---------------
 1 files changed, 95 insertions(+), 36 deletions(-)

Comments

David Miller Jan. 22, 2009, 10:11 p.m. UTC | #1 
From: Timo Teras <timo.teras@iki.fi>
Date: Thu, 22 Jan 2009 09:24:44 +0200

> Updated as requested. Compile tested.
> Sent as new patch since I haven't seen the earlier patch pushed yet.

It is there in the net-next-2.6 tree, please therefore
send a relative fixup.

Thanks.
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diff mbox

Patch

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 0101521..07a188a 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -164,67 +164,124 @@  static DEFINE_RWLOCK(ipgre_lock);
 
 /* 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, *cand = 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 score, cand_score = 4;
 
 	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;
+
+		score = 0;
+		if (t->parms.link != link)
+			score |= 1;
+		if (t->dev->type != dev_type)
+			score |= 2;
+		if (score == 0)
+			return t;
+
+		if (score < cand_score) {
+			cand = t;
+			cand_score = score;
 		}
 	}
 
 	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;
+
+		score = 0;
+		if (t->parms.link != link)
+			score |= 1;
+		if (t->dev->type != dev_type)
+			score |= 2;
+		if (score == 0)
+			return t;
+
+		if (score < cand_score) {
+			cand = t;
+			cand_score = score;
 		}
 	}
 
 	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;
+
+		score = 0;
+		if (t->parms.link != link)
+			score |= 1;
+		if (t->dev->type != dev_type)
+			score |= 2;
+		if (score == 0)
+			return t;
+
+		if (score < cand_score) {
+			cand = t;
+			cand_score = score;
 		}
 	}
 
 	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;
+
+		score = 0;
+		if (t->parms.link != link)
+			score |= 1;
+		if (t->dev->type != dev_type)
+			score |= 2;
+		if (score == 0)
+			return t;
+
+		if (score < cand_score) {
+			cand = t;
+			cand_score = score;
 		}
 	}
 
-	if (t2)
-		return t2;
+	if (cand != NULL)
+		return cand;
 
-	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 +341,7 @@  static struct ip_tunnel *ipgre_tunnel_find(struct net *net,
 	__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 +349,7 @@  static struct ip_tunnel *ipgre_tunnel_find(struct net *net,
 		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 +480,7 @@  static void ipgre_err(struct sk_buff *skb, u32 info)
 	}
 
 	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 +577,7 @@  static int ipgre_rcv(struct sk_buff *skb)
 	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;