gre: receive also TEB packets for lwtunnels
authorJiri Benc <jbenc@redhat.com>
Tue, 3 May 2016 15:10:08 +0000 (17:10 +0200)
committerDavid S. Miller <davem@davemloft.net>
Wed, 4 May 2016 18:11:32 +0000 (14:11 -0400)
For ipgre interfaces in collect metadata mode, receive also traffic with
encapsulated Ethernet headers. The lwtunnel users are supposed to sort this
out correctly. This allows to have mixed Ethernet + L3-only traffic on the
same lwtunnel interface. This is the same way as VXLAN-GPE behaves.

To keep backwards compatibility and prevent any surprises, gretap interfaces
have priority in receiving packets with Ethernet headers.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/net/ip_tunnels.h
net/ipv4/ip_gre.c

index 6d790910ebdfdeb7f371a0471b38a49608b5131c..d916b43159033f33ad8f5ad59b0434540ccfe51f 100644 (file)
@@ -160,6 +160,7 @@ struct tnl_ptk_info {
 
 #define PACKET_RCVD    0
 #define PACKET_REJECT  1
+#define PACKET_NEXT    2
 
 #define IP_TNL_HASH_BITS   7
 #define IP_TNL_HASH_SIZE   (1 << IP_TNL_HASH_BITS)
index 8f377dad548943bc6769c335bafdccf164b698be..2b267e71ebf5f25dc38587c6b7922b93e890694f 100644 (file)
@@ -260,26 +260,20 @@ static __be32 tunnel_id_to_key(__be64 x)
 #endif
 }
 
-static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
-                    int hdr_len)
+static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
+                      struct ip_tunnel_net *itn, int hdr_len, bool raw_proto)
 {
-       struct net *net = dev_net(skb->dev);
        struct metadata_dst *tun_dst = NULL;
-       struct ip_tunnel_net *itn;
        const struct iphdr *iph;
        struct ip_tunnel *tunnel;
 
-       if (tpi->proto == htons(ETH_P_TEB))
-               itn = net_generic(net, gre_tap_net_id);
-       else
-               itn = net_generic(net, ipgre_net_id);
-
        iph = ip_hdr(skb);
        tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
                                  iph->saddr, iph->daddr, tpi->key);
 
        if (tunnel) {
-               if (iptunnel_pull_header(skb, hdr_len, tpi->proto, false) < 0)
+               if (__iptunnel_pull_header(skb, hdr_len, tpi->proto,
+                                          raw_proto, false) < 0)
                        goto drop;
 
                skb_pop_mac_header(skb);
@@ -297,13 +291,36 @@ static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
                ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
                return PACKET_RCVD;
        }
-       return PACKET_REJECT;
+       return PACKET_NEXT;
 
 drop:
        kfree_skb(skb);
        return PACKET_RCVD;
 }
 
+static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
+                    int hdr_len)
+{
+       struct net *net = dev_net(skb->dev);
+       struct ip_tunnel_net *itn;
+       int res;
+
+       if (tpi->proto == htons(ETH_P_TEB))
+               itn = net_generic(net, gre_tap_net_id);
+       else
+               itn = net_generic(net, ipgre_net_id);
+
+       res = __ipgre_rcv(skb, tpi, itn, hdr_len, false);
+       if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) {
+               /* ipgre tunnels in collect metadata mode should receive
+                * also ETH_P_TEB traffic.
+                */
+               itn = net_generic(net, ipgre_net_id);
+               res = __ipgre_rcv(skb, tpi, itn, hdr_len, true);
+       }
+       return res;
+}
+
 static int gre_rcv(struct sk_buff *skb)
 {
        struct tnl_ptk_info tpi;