[NETFILTER]: bridge netfilter: consolidate header pushing/pulling code

Consolidate the common push/pull sequences into a few helper functions.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 56 insertions, 107 deletions

diff --git a/include/linux/netfilter_bridge.h b/include/linux/netfilter_bridge.h
index 19060030bac9..533ee351a273 100644
--- a/include/linux/netfilter_bridge.h
+++ b/include/linux/netfilter_bridge.h
@@ -55,18 +55,25 @@ static inline int nf_bridge_maybe_copy_header(struct sk_buff *skb)
         return 0;
 }
 
+static inline unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
+{
+        switch (skb->protocol) {
+        case __constant_htons(ETH_P_8021Q):
+                return VLAN_HLEN;
+        case __constant_htons(ETH_P_PPP_SES):
+                return PPPOE_SES_HLEN;
+        default:
+                return 0;
+        }
+}
+
 /* This is called by the IP fragmenting code and it ensures there is
  * enough room for the encapsulating header (if there is one). */
-static inline int nf_bridge_pad(const struct sk_buff *skb)
+static inline unsigned int nf_bridge_pad(const struct sk_buff *skb)
 {
-        int padding = 0;
-
-        if (skb->nf_bridge && skb->protocol == htons(ETH_P_8021Q))
-                padding = VLAN_HLEN;
-        else if (skb->nf_bridge && skb->protocol == htons(ETH_P_PPP_SES))
-                padding = PPPOE_SES_HLEN;
-
-        return padding;
+        if (skb->nf_bridge)
+                return nf_bridge_encap_header_len(skb);
+        return 0;
 }
 
 struct bridge_skb_cb {
diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index 9b2986b182ba..fa779874b9dd 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -142,14 +142,33 @@ static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
         return skb->nf_bridge;
 }
 
-static inline void nf_bridge_save_header(struct sk_buff *skb)
+static inline void nf_bridge_push_encap_header(struct sk_buff *skb)
+{
+        unsigned int len = nf_bridge_encap_header_len(skb);
+
+        skb_push(skb, len);
+        skb->network_header -= len;
+}
+
+static inline void nf_bridge_pull_encap_header(struct sk_buff *skb)
 {
-        int header_size = ETH_HLEN;
+        unsigned int len = nf_bridge_encap_header_len(skb);
+
+        skb_pull(skb, len);
+        skb->network_header += len;
+}
 
-        if (skb->protocol == htons(ETH_P_8021Q))
-                header_size += VLAN_HLEN;
-        else if (skb->protocol == htons(ETH_P_PPP_SES))
-                header_size += PPPOE_SES_HLEN;
+static inline void nf_bridge_pull_encap_header_rcsum(struct sk_buff *skb)
+{
+        unsigned int len = nf_bridge_encap_header_len(skb);
+
+        skb_pull_rcsum(skb, len);
+        skb->network_header += len;
+}
+
+static inline void nf_bridge_save_header(struct sk_buff *skb)
+{
+        int header_size = ETH_HLEN + nf_bridge_encap_header_len(skb);
 
         skb_copy_from_linear_data_offset(skb, -header_size,
                                          skb->nf_bridge->data, header_size);
@@ -162,12 +181,7 @@ static inline void nf_bridge_save_header(struct sk_buff *skb)
 int nf_bridge_copy_header(struct sk_buff *skb)
 {
         int err;
-        int header_size = ETH_HLEN;
-
-        if (skb->protocol == htons(ETH_P_8021Q))
-                header_size += VLAN_HLEN;
-        else if (skb->protocol == htons(ETH_P_PPP_SES))
-                header_size += PPPOE_SES_HLEN;
+        int header_size = ETH_HLEN + nf_bridge_encap_header_len(skb);
 
         err = skb_cow(skb, header_size);
         if (err)
@@ -175,11 +189,7 @@ int nf_bridge_copy_header(struct sk_buff *skb)
 
         skb_copy_to_linear_data_offset(skb, -header_size,
                                        skb->nf_bridge->data, header_size);
-
-        if (skb->protocol == htons(ETH_P_8021Q))
-                __skb_push(skb, VLAN_HLEN);
-        else if (skb->protocol == htons(ETH_P_PPP_SES))
-                __skb_push(skb, PPPOE_SES_HLEN);
+        __skb_push(skb, nf_bridge_encap_header_len(skb));
         return 0;
 }
 
@@ -200,13 +210,7 @@ static int br_nf_pre_routing_finish_ipv6(struct sk_buff *skb)
         dst_hold(skb->dst);
 
         skb->dev = nf_bridge->physindev;
-        if (skb->protocol == htons(ETH_P_8021Q)) {
-                skb_push(skb, VLAN_HLEN);
-                skb->network_header -= VLAN_HLEN;
-        } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                skb_push(skb, PPPOE_SES_HLEN);
-                skb->network_header -= PPPOE_SES_HLEN;
-        }
+        nf_bridge_push_encap_header(skb);
         NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
                        br_handle_frame_finish, 1);
 
@@ -284,13 +288,7 @@ static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
         if (!skb->dev)
                 kfree_skb(skb);
         else {
-                if (skb->protocol == htons(ETH_P_8021Q)) {
-                        skb_pull(skb, VLAN_HLEN);
-                        skb->network_header += VLAN_HLEN;
-                } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                        skb_pull(skb, PPPOE_SES_HLEN);
-                        skb->network_header += PPPOE_SES_HLEN;
-                }
+                nf_bridge_pull_encap_header(skb);
                 skb->dst->output(skb);
         }
         return 0;
@@ -356,15 +354,7 @@ bridged_dnat:
                                  * bridged frame */
                                 nf_bridge->mask |= BRNF_BRIDGED_DNAT;
                                 skb->dev = nf_bridge->physindev;
-                                if (skb->protocol ==
-                                    htons(ETH_P_8021Q)) {
-                                        skb_push(skb, VLAN_HLEN);
-                                        skb->network_header -= VLAN_HLEN;
-                                } else if(skb->protocol ==
-                                    htons(ETH_P_PPP_SES)) {
-                                        skb_push(skb, PPPOE_SES_HLEN);
-                                        skb->network_header -= PPPOE_SES_HLEN;
-                                }
+                                nf_bridge_push_encap_header(skb);
                                 NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING,
                                                skb, skb->dev, NULL,
                                                br_nf_pre_routing_finish_bridge,
@@ -380,13 +370,7 @@ bridged_dnat:
         }
 
         skb->dev = nf_bridge->physindev;
-        if (skb->protocol == htons(ETH_P_8021Q)) {
-                skb_push(skb, VLAN_HLEN);
-                skb->network_header -= VLAN_HLEN;
-        } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                skb_push(skb, PPPOE_SES_HLEN);
-                skb->network_header -= PPPOE_SES_HLEN;
-        }
+        nf_bridge_push_encap_header(skb);
         NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
                        br_handle_frame_finish, 1);
 
@@ -536,14 +520,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb,
 #endif
                 if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL)
                         goto out;
-
-                if (skb->protocol == htons(ETH_P_8021Q)) {
-                        skb_pull_rcsum(skb, VLAN_HLEN);
-                        skb->network_header += VLAN_HLEN;
-                } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                        skb_pull_rcsum(skb, PPPOE_SES_HLEN);
-                        skb->network_header += PPPOE_SES_HLEN;
-                }
+                nf_bridge_pull_encap_header_rcsum(skb);
                 return br_nf_pre_routing_ipv6(hook, skb, in, out, okfn);
         }
 #ifdef CONFIG_SYSCTL
@@ -557,14 +534,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb,
 
         if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL)
                 goto out;
-
-        if (skb->protocol == htons(ETH_P_8021Q)) {
-                skb_pull_rcsum(skb, VLAN_HLEN);
-                skb->network_header += VLAN_HLEN;
-        } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                skb_pull_rcsum(skb, PPPOE_SES_HLEN);
-                skb->network_header += PPPOE_SES_HLEN;
-        }
+        nf_bridge_pull_encap_header_rcsum(skb);
 
         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
                 goto inhdr_error;
@@ -642,13 +612,7 @@ static int br_nf_forward_finish(struct sk_buff *skb)
         } else {
                 in = *((struct net_device **)(skb->cb));
         }
-        if (skb->protocol == htons(ETH_P_8021Q)) {
-                skb_push(skb, VLAN_HLEN);
-                skb->network_header -= VLAN_HLEN;
-        } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                skb_push(skb, PPPOE_SES_HLEN);
-                skb->network_header -= PPPOE_SES_HLEN;
-        }
+        nf_bridge_push_encap_header(skb);
         NF_HOOK_THRESH(PF_BRIDGE, NF_BR_FORWARD, skb, in,
                        skb->dev, br_forward_finish, 1);
         return 0;
@@ -682,13 +646,7 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff **pskb,
         else
                 pf = PF_INET6;
 
-        if (skb->protocol == htons(ETH_P_8021Q)) {
-                skb_pull(*pskb, VLAN_HLEN);
-                (*pskb)->network_header += VLAN_HLEN;
-        } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                skb_pull(*pskb, PPPOE_SES_HLEN);
-                (*pskb)->network_header += PPPOE_SES_HLEN;
-        }
+        nf_bridge_pull_encap_header(*pskb);
 
         nf_bridge = skb->nf_bridge;
         if (skb->pkt_type == PACKET_OTHERHOST) {
@@ -722,15 +680,12 @@ 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;
-                skb_pull(*pskb, VLAN_HLEN);
-                (*pskb)->network_header += VLAN_HLEN;
+                nf_bridge_pull_encap_header(*pskb);
         }
 
         if (arp_hdr(skb)->ar_pln != 4) {
-                if (IS_VLAN_ARP(skb)) {
-                        skb_push(*pskb, VLAN_HLEN);
-                        (*pskb)->network_header -= VLAN_HLEN;
-                }
+                if (IS_VLAN_ARP(skb))
+                        nf_bridge_push_encap_header(*pskb);
                 return NF_ACCEPT;
         }
         *d = (struct net_device *)in;
@@ -777,13 +732,7 @@ static unsigned int br_nf_local_out(unsigned int hook, struct sk_buff **pskb,
                 skb->pkt_type = PACKET_OTHERHOST;
                 nf_bridge->mask ^= BRNF_PKT_TYPE;
         }
-        if (skb->protocol == htons(ETH_P_8021Q)) {
-                skb_push(skb, VLAN_HLEN);
-                skb->network_header -= VLAN_HLEN;
-        } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                skb_push(skb, PPPOE_SES_HLEN);
-                skb->network_header -= PPPOE_SES_HLEN;
-        }
+        nf_bridge_push_encap_header(skb);
 
         NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, realindev, skb->dev,
                 br_forward_finish);
@@ -848,14 +797,7 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb,
                 nf_bridge->mask |= BRNF_PKT_TYPE;
         }
 
-        if (skb->protocol == htons(ETH_P_8021Q)) {
-                skb_pull(skb, VLAN_HLEN);
-                skb->network_header += VLAN_HLEN;
-        } else if (skb->protocol == htons(ETH_P_PPP_SES)) {
-                skb_pull(skb, PPPOE_SES_HLEN);
-                skb->network_header += PPPOE_SES_HLEN;
-        }
-
+        nf_bridge_pull_encap_header(skb);
         nf_bridge_save_header(skb);
 
 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)