This adds the capability to conntrack 802.1ad, QinQ, PPPoE and PPPoE-in-Q
packets that are passing a bridge, only when a conntrack zone is set.

Signed-off-by: Eric Woudstra <ericwo...@gmail.com>
---
 net/bridge/netfilter/nf_conntrack_bridge.c | 88 ++++++++++++++++++----
 1 file changed, 72 insertions(+), 16 deletions(-)

diff --git a/net/bridge/netfilter/nf_conntrack_bridge.c 
b/net/bridge/netfilter/nf_conntrack_bridge.c
index 6482de4d8750..5fcb1bdf2e31 100644
--- a/net/bridge/netfilter/nf_conntrack_bridge.c
+++ b/net/bridge/netfilter/nf_conntrack_bridge.c
@@ -242,53 +242,109 @@ static unsigned int nf_ct_bridge_pre(void *priv, struct 
sk_buff *skb,
 {
        struct nf_hook_state bridge_state = *state;
        enum ip_conntrack_info ctinfo;
+       u32 len, data_len = U32_MAX;
+       int ret, offset = 0;
        struct nf_conn *ct;
-       u32 len;
-       int ret;
+       __be16 outer_proto;
 
        ct = nf_ct_get(skb, &ctinfo);
        if ((ct && !nf_ct_is_template(ct)) ||
            ctinfo == IP_CT_UNTRACKED)
                return NF_ACCEPT;
 
+       if (ct && nf_ct_zone_id(nf_ct_zone(ct), CTINFO2DIR(ctinfo)) !=
+                       NF_CT_DEFAULT_ZONE_ID) {
+               switch (skb->protocol) {
+               case htons(ETH_P_PPP_SES): {
+                       struct ppp_hdr {
+                               struct pppoe_hdr hdr;
+                               __be16 proto;
+                       } *ph;
+
+                       offset = PPPOE_SES_HLEN;
+                       if (!pskb_may_pull(skb, offset))
+                               return NF_ACCEPT;
+                       outer_proto = skb->protocol;
+                       ph = (struct ppp_hdr *)(skb->data);
+                       switch (ph->proto) {
+                       case htons(PPP_IP):
+                               skb->protocol = htons(ETH_P_IP);
+                               break;
+                       case htons(PPP_IPV6):
+                               skb->protocol = htons(ETH_P_IPV6);
+                               break;
+                       default:
+                               nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
+                               return NF_ACCEPT;
+                       }
+                       data_len = ntohs(ph->hdr.length) - 2;
+                       skb_set_network_header(skb, offset);
+                       break;
+               }
+               case htons(ETH_P_8021Q): {
+                       struct vlan_hdr *vhdr;
+
+                       offset = VLAN_HLEN;
+                       if (!pskb_may_pull(skb, offset))
+                               return NF_ACCEPT;
+                       outer_proto = skb->protocol;
+                       vhdr = (struct vlan_hdr *)(skb->data);
+                       skb->protocol = vhdr->h_vlan_encapsulated_proto;
+                       data_len = U32_MAX;
+                       skb_set_network_header(skb, offset);
+                       break;
+               }
+               }
+       }
+
+       ret = NF_ACCEPT;
        switch (skb->protocol) {
        case htons(ETH_P_IP):
-               if (!pskb_may_pull(skb, sizeof(struct iphdr)))
-                       return NF_ACCEPT;
+               if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
+                       goto do_not_track;
 
                len = skb_ip_totlen(skb);
-               if (pskb_trim_rcsum(skb, len))
-                       return NF_ACCEPT;
+               if (data_len < len)
+                       len = data_len;
+               if (pskb_trim_rcsum(skb, len + offset))
+                       goto do_not_track;
 
                if (nf_ct_br_ip_check(skb))
-                       return NF_ACCEPT;
+                       goto do_not_track;
 
                bridge_state.pf = NFPROTO_IPV4;
                ret = nf_ct_br_defrag4(skb, &bridge_state);
                break;
        case htons(ETH_P_IPV6):
-               if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
-                       return NF_ACCEPT;
+               if (!pskb_may_pull(skb, offset + sizeof(struct ipv6hdr)))
+                       goto do_not_track;
 
                len = sizeof(struct ipv6hdr) + 
ntohs(ipv6_hdr(skb)->payload_len);
-               if (pskb_trim_rcsum(skb, len))
-                       return NF_ACCEPT;
+               if (data_len < len)
+                       len = data_len;
+               if (pskb_trim_rcsum(skb, len + offset))
+                       goto do_not_track;
 
                if (nf_ct_br_ipv6_check(skb))
-                       return NF_ACCEPT;
+                       goto do_not_track;
 
                bridge_state.pf = NFPROTO_IPV6;
                ret = nf_ct_br_defrag6(skb, &bridge_state);
                break;
        default:
                nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
-               return NF_ACCEPT;
+               goto do_not_track;
        }
 
-       if (ret != NF_ACCEPT)
-               return ret;
+       if (ret == NF_ACCEPT)
+               ret = nf_conntrack_in(skb, &bridge_state);
 
-       return nf_conntrack_in(skb, &bridge_state);
+do_not_track:
+       if (offset) {
+               skb_reset_network_header(skb);
+               skb->protocol = outer_proto;
+       }
+       return ret;
 }
 
 static unsigned int nf_ct_bridge_in(void *priv, struct sk_buff *skb,
-- 
2.47.1


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