[NETFILTER]: Introduce NF_INET_ hook values
[safe/jmp/linux-2.6] / net / bridge / br_netfilter.c
index 8245f05..f9ef3e5 100644 (file)
@@ -142,6 +142,23 @@ static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
        return skb->nf_bridge;
 }
 
+static inline struct nf_bridge_info *nf_bridge_unshare(struct sk_buff *skb)
+{
+       struct nf_bridge_info *nf_bridge = skb->nf_bridge;
+
+       if (atomic_read(&nf_bridge->use) > 1) {
+               struct nf_bridge_info *tmp = nf_bridge_alloc(skb);
+
+               if (tmp) {
+                       memcpy(tmp, nf_bridge, sizeof(struct nf_bridge_info));
+                       atomic_set(&tmp->use, 1);
+                       nf_bridge_put(nf_bridge);
+               }
+               nf_bridge = tmp;
+       }
+       return nf_bridge;
+}
+
 static inline void nf_bridge_push_encap_header(struct sk_buff *skb)
 {
        unsigned int len = nf_bridge_encap_header_len(skb);
@@ -247,8 +264,9 @@ static void __br_dnat_complain(void)
  * Let us first consider the case that ip_route_input() succeeds:
  *
  * If skb->dst->dev equals the logical bridge device the packet
- * came in on, we can consider this bridging. We then call
- * skb->dst->output() which will make the packet enter br_nf_local_out()
+ * came in on, we can consider this bridging. The packet is passed
+ * through the neighbour output function to build a new destination
+ * MAC address, which will make the packet enter br_nf_local_out()
  * not much later. In that function it is assured that the iptables
  * FORWARD chain is traversed for the packet.
  *
@@ -285,12 +303,17 @@ static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
        skb->nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING;
 
        skb->dev = bridge_parent(skb->dev);
-       if (!skb->dev)
-               kfree_skb(skb);
-       else {
+       if (skb->dev) {
+               struct dst_entry *dst = skb->dst;
+
                nf_bridge_pull_encap_header(skb);
-               skb->dst->output(skb);
+
+               if (dst->hh)
+                       return neigh_hh_output(dst->hh, skb);
+               else if (dst->neighbour)
+                       return dst->neighbour->output(skb);
        }
+       kfree_skb(skb);
        return 0;
 }
 
@@ -488,7 +511,7 @@ static unsigned int br_nf_pre_routing_ipv6(unsigned int hook,
        if (!setup_pre_routing(skb))
                return NF_DROP;
 
-       NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
+       NF_HOOK(PF_INET6, NF_INET_PRE_ROUTING, skb, skb->dev, NULL,
                br_nf_pre_routing_finish_ipv6);
 
        return NF_STOLEN;
@@ -503,18 +526,14 @@ inhdr_error:
  * receiving device) to make netfilter happy, the REDIRECT
  * target in particular.  Save the original destination IP
  * address to be able to detect DNAT afterwards. */
-static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb,
+static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff *skb,
                                      const struct net_device *in,
                                      const struct net_device *out,
                                      int (*okfn)(struct sk_buff *))
 {
        struct iphdr *iph;
-       struct sk_buff *skb = *pskb;
        __u32 len = nf_bridge_encap_header_len(skb);
 
-       if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
-               return NF_STOLEN;
-
        if (unlikely(!pskb_may_pull(skb, len)))
                goto out;
 
@@ -565,7 +584,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb,
                return NF_DROP;
        store_orig_dstaddr(skb);
 
-       NF_HOOK(PF_INET, NF_IP_PRE_ROUTING, skb, skb->dev, NULL,
+       NF_HOOK(PF_INET, NF_INET_PRE_ROUTING, skb, skb->dev, NULL,
                br_nf_pre_routing_finish);
 
        return NF_STOLEN;
@@ -584,13 +603,11 @@ out:
  * took place when the packet entered the bridge), but we
  * register an IPv4 PRE_ROUTING 'sabotage' hook that will
  * prevent this from happening. */
-static unsigned int br_nf_local_in(unsigned int hook, struct sk_buff **pskb,
+static unsigned int br_nf_local_in(unsigned int hook, struct sk_buff *skb,
                                   const struct net_device *in,
                                   const struct net_device *out,
                                   int (*okfn)(struct sk_buff *))
 {
-       struct sk_buff *skb = *pskb;
-
        if (skb->dst == (struct dst_entry *)&__fake_rtable) {
                dst_release(skb->dst);
                skb->dst = NULL;
@@ -625,12 +642,11 @@ static int br_nf_forward_finish(struct sk_buff *skb)
  * but we are still able to filter on the 'real' indev/outdev
  * because of the physdev module. For ARP, indev and outdev are the
  * bridge ports. */
-static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff **pskb,
+static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff *skb,
                                     const struct net_device *in,
                                     const struct net_device *out,
                                     int (*okfn)(struct sk_buff *))
 {
-       struct sk_buff *skb = *pskb;
        struct nf_bridge_info *nf_bridge;
        struct net_device *parent;
        int pf;
@@ -638,6 +654,11 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff **pskb,
        if (!skb->nf_bridge)
                return NF_ACCEPT;
 
+       /* Need exclusive nf_bridge_info since we might have multiple
+        * different physoutdevs. */
+       if (!nf_bridge_unshare(skb))
+               return NF_DROP;
+
        parent = bridge_parent(out);
        if (!parent)
                return NF_DROP;
@@ -648,7 +669,7 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff **pskb,
        else
                pf = PF_INET6;
 
-       nf_bridge_pull_encap_header(*pskb);
+       nf_bridge_pull_encap_header(skb);
 
        nf_bridge = skb->nf_bridge;
        if (skb->pkt_type == PACKET_OTHERHOST) {
@@ -660,18 +681,17 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff **pskb,
        nf_bridge->mask |= BRNF_BRIDGED;
        nf_bridge->physoutdev = skb->dev;
 
-       NF_HOOK(pf, NF_IP_FORWARD, skb, bridge_parent(in), parent,
+       NF_HOOK(pf, NF_INET_FORWARD, skb, bridge_parent(in), parent,
                br_nf_forward_finish);
 
        return NF_STOLEN;
 }
 
-static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff **pskb,
+static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff *skb,
                                      const struct net_device *in,
                                      const struct net_device *out,
                                      int (*okfn)(struct sk_buff *))
 {
-       struct sk_buff *skb = *pskb;
        struct net_device **d = (struct net_device **)(skb->cb);
 
 #ifdef CONFIG_SYSCTL
@@ -682,12 +702,12 @@ static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff **pskb,
        if (skb->protocol != htons(ETH_P_ARP)) {
                if (!IS_VLAN_ARP(skb))
                        return NF_ACCEPT;
-               nf_bridge_pull_encap_header(*pskb);
+               nf_bridge_pull_encap_header(skb);
        }
 
        if (arp_hdr(skb)->ar_pln != 4) {
                if (IS_VLAN_ARP(skb))
-                       nf_bridge_push_encap_header(*pskb);
+                       nf_bridge_push_encap_header(skb);
                return NF_ACCEPT;
        }
        *d = (struct net_device *)in;
@@ -709,18 +729,22 @@ static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff **pskb,
  * NF_BR_PRI_FIRST, so no relevant PF_BRIDGE/INPUT functions have been nor
  * will be executed.
  */
-static unsigned int br_nf_local_out(unsigned int hook, struct sk_buff **pskb,
+static unsigned int br_nf_local_out(unsigned int hook, struct sk_buff *skb,
                                    const struct net_device *in,
                                    const struct net_device *out,
                                    int (*okfn)(struct sk_buff *))
 {
        struct net_device *realindev;
-       struct sk_buff *skb = *pskb;
        struct nf_bridge_info *nf_bridge;
 
        if (!skb->nf_bridge)
                return NF_ACCEPT;
 
+       /* Need exclusive nf_bridge_info since we might have multiple
+        * different physoutdevs. */
+       if (!nf_bridge_unshare(skb))
+               return NF_DROP;
+
        nf_bridge = skb->nf_bridge;
        if (!(nf_bridge->mask & BRNF_BRIDGED_DNAT))
                return NF_ACCEPT;
@@ -752,13 +776,12 @@ static int br_nf_dev_queue_xmit(struct sk_buff *skb)
 }
 
 /* PF_BRIDGE/POST_ROUTING ********************************************/
-static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb,
+static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff *skb,
                                       const struct net_device *in,
                                       const struct net_device *out,
                                       int (*okfn)(struct sk_buff *))
 {
-       struct sk_buff *skb = *pskb;
-       struct nf_bridge_info *nf_bridge = (*pskb)->nf_bridge;
+       struct nf_bridge_info *nf_bridge = skb->nf_bridge;
        struct net_device *realoutdev = bridge_parent(skb->dev);
        int pf;
 
@@ -776,6 +799,9 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb,
        if (!nf_bridge)
                return NF_ACCEPT;
 
+       if (!(nf_bridge->mask & (BRNF_BRIDGED | BRNF_BRIDGED_DNAT)))
+               return NF_ACCEPT;
+
        if (!realoutdev)
                return NF_DROP;
 
@@ -806,7 +832,7 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb,
        if (nf_bridge->netoutdev)
                realoutdev = nf_bridge->netoutdev;
 #endif
-       NF_HOOK(pf, NF_IP_POST_ROUTING, skb, NULL, realoutdev,
+       NF_HOOK(pf, NF_INET_POST_ROUTING, skb, NULL, realoutdev,
                br_nf_dev_queue_xmit);
 
        return NF_STOLEN;
@@ -828,13 +854,13 @@ print_error:
 /* IP/SABOTAGE *****************************************************/
 /* Don't hand locally destined packets to PF_INET(6)/PRE_ROUTING
  * for the second time. */
-static unsigned int ip_sabotage_in(unsigned int hook, struct sk_buff **pskb,
+static unsigned int ip_sabotage_in(unsigned int hook, struct sk_buff *skb,
                                   const struct net_device *in,
                                   const struct net_device *out,
                                   int (*okfn)(struct sk_buff *))
 {
-       if ((*pskb)->nf_bridge &&
-           !((*pskb)->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)) {
+       if (skb->nf_bridge &&
+           !(skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)) {
                return NF_STOP;
        }
 
@@ -879,12 +905,12 @@ static struct nf_hook_ops br_nf_ops[] = {
        { .hook = ip_sabotage_in,
          .owner = THIS_MODULE,
          .pf = PF_INET,
-         .hooknum = NF_IP_PRE_ROUTING,
+         .hooknum = NF_INET_PRE_ROUTING,
          .priority = NF_IP_PRI_FIRST, },
        { .hook = ip_sabotage_in,
          .owner = THIS_MODULE,
          .pf = PF_INET6,
-         .hooknum = NF_IP6_PRE_ROUTING,
+         .hooknum = NF_INET_PRE_ROUTING,
          .priority = NF_IP6_PRI_FIRST, },
 };