ip_tunnel: push generic protocol handling to ip_tunnel module.

Process skb tunnel header before sending packet to protocol handler.
this allows code sharing between gre and ovs gre modules.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 53 insertions, 27 deletions

diff --git a/net/ipv4/gre.c b/net/ipv4/gre.c
index 5ecc9c49b4dc..ba4803e609b5 100644
--- a/net/ipv4/gre.c
+++ b/net/ipv4/gre.c
@@ -201,7 +201,8 @@ static int parse_gre_header(struct sk_buff *skb, struct tnl_ptk_info *tpi,
                                 return -EINVAL;
                 }
         }
-        return 0;
+
+        return iptunnel_pull_header(skb, hdr_len, tpi->proto);
 }
 
 static int gre_cisco_rcv(struct sk_buff *skb)
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index a06a2ed49597..bd227e5ea9da 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -408,13 +408,6 @@ int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
         const struct iphdr *iph = ip_hdr(skb);
         int err;
 
-        secpath_reset(skb);
-
-        skb->protocol = tpi->proto;
-
-        skb->mac_header = skb->network_header;
-        __pskb_pull(skb, tunnel->hlen);
-        skb_postpull_rcsum(skb, skb_transport_header(skb), tunnel->hlen);
 #ifdef CONFIG_NET_IPGRE_BROADCAST
         if (ipv4_is_multicast(iph->daddr)) {
                 /* Looped back packet, drop it! */
@@ -442,23 +435,6 @@ int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
                 tunnel->i_seqno = ntohl(tpi->seq) + 1;
         }
 
-        /* Warning: All skb pointers will be invalidated! */
-        if (tunnel->dev->type == ARPHRD_ETHER) {
-                if (!pskb_may_pull(skb, ETH_HLEN)) {
-                        tunnel->dev->stats.rx_length_errors++;
-                        tunnel->dev->stats.rx_errors++;
-                        goto drop;
-                }
-
-                iph = ip_hdr(skb);
-                skb->protocol = eth_type_trans(skb, tunnel->dev);
-                skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
-        }
-
-        skb->pkt_type = PACKET_HOST;
-        __skb_tunnel_rx(skb, tunnel->dev);
-
-        skb_reset_network_header(skb);
         err = IP_ECN_decapsulate(iph, skb);
         if (unlikely(err)) {
                 if (log_ecn_error)
@@ -477,6 +453,12 @@ int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
         tstats->rx_bytes += skb->len;
         u64_stats_update_end(&tstats->syncp);
 
+        if (tunnel->dev->type == ARPHRD_ETHER) {
+                skb->protocol = eth_type_trans(skb, tunnel->dev);
+                skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
+        } else {
+                skb->dev = tunnel->dev;
+        }
         gro_cells_receive(&tunnel->gro_cells, skb);
         return 0;
 
diff --git a/net/ipv4/ip_tunnel_core.c b/net/ipv4/ip_tunnel_core.c
index 927687e83f18..7167b08977df 100644
--- a/net/ipv4/ip_tunnel_core.c
+++ b/net/ipv4/ip_tunnel_core.c
@@ -86,3 +86,37 @@ int iptunnel_xmit(struct net *net, struct rtable *rt,
         return pkt_len;
 }
 EXPORT_SYMBOL_GPL(iptunnel_xmit);
+
+int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto)
+{
+        if (unlikely(!pskb_may_pull(skb, hdr_len)))
+                return -ENOMEM;
+
+        skb_pull_rcsum(skb, hdr_len);
+
+        if (inner_proto == htons(ETH_P_TEB)) {
+                struct ethhdr *eh = (struct ethhdr *)skb->data;
+
+                if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
+                        return -ENOMEM;
+
+                if (likely(ntohs(eh->h_proto) >= ETH_P_802_3_MIN))
+                        skb->protocol = eh->h_proto;
+                else
+                        skb->protocol = htons(ETH_P_802_2);
+
+        } else {
+                skb->protocol = inner_proto;
+        }
+
+        nf_reset(skb);
+        secpath_reset(skb);
+        if (!skb->l4_rxhash)
+                skb->rxhash = 0;
+        skb_dst_drop(skb);
+        skb->vlan_tci = 0;
+        skb_set_queue_mapping(skb, 0);
+        skb->pkt_type = PACKET_HOST;
+        return 0;
+}
+EXPORT_SYMBOL_GPL(iptunnel_pull_header);
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 9df7ecd393f2..e6905fbda2a2 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -188,8 +188,12 @@ static int ipip_rcv(struct sk_buff *skb)
         struct net *net = dev_net(skb->dev);
         struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
         struct ip_tunnel *tunnel;
-        const struct iphdr *iph = ip_hdr(skb);
+        const struct iphdr *iph;
 
+        if (iptunnel_pull_header(skb, 0, tpi.proto))
+                goto drop;
+
+        iph = ip_hdr(skb);
         tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
                         iph->saddr, iph->daddr, 0);
         if (tunnel) {
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 76bb8de435b2..6cee844678e2 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -640,9 +640,14 @@ static const struct tnl_ptk_info tpi = {
 
 static int ipip_rcv(struct sk_buff *skb)
 {
-        const struct iphdr *iph = ip_hdr(skb);
+        const struct iphdr *iph;
         struct ip_tunnel *tunnel;
 
+        if (iptunnel_pull_header(skb, 0, tpi.proto))
+                goto drop;
+
+        iph = ip_hdr(skb);
+
         tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
                                      iph->saddr, iph->daddr);
         if (tunnel != NULL) {