From 07317621d004e8e6967f2dac8562825267e56135 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Tue, 29 Aug 2006 17:48:17 -0700 Subject: [PATCH] [NETFILTER] bridge: code rearrangement for clarity Cleanup and rearrangement for better style and clarity: Split the function nf_bridge_maybe_copy_header into two pieces Move copy portion out of line. Use Ethernet header size macros. Use header file to handle CONFIG_NETFILTER_BRIDGE differences Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- include/linux/netfilter_bridge.h | 26 +++++++------------------- net/bridge/br_forward.c | 5 +---- net/bridge/br_netfilter.c | 27 +++++++++++++++++++++++++-- 3 files changed, 33 insertions(+), 25 deletions(-) diff --git a/include/linux/netfilter_bridge.h b/include/linux/netfilter_bridge.h index 427c67ff89..274fe4b331 100644 --- a/include/linux/netfilter_bridge.h +++ b/include/linux/netfilter_bridge.h @@ -47,26 +47,12 @@ enum nf_br_hook_priorities { /* Only used in br_forward.c */ -static inline -int nf_bridge_maybe_copy_header(struct sk_buff *skb) +extern int nf_bridge_copy_header(struct sk_buff *skb); +static inline int nf_bridge_maybe_copy_header(struct sk_buff *skb) { - int err; - - if (skb->nf_bridge) { - if (skb->protocol == __constant_htons(ETH_P_8021Q)) { - err = skb_cow(skb, 18); - if (err) - return err; - memcpy(skb->data - 18, skb->nf_bridge->data, 18); - skb_push(skb, 4); - } else { - err = skb_cow(skb, 16); - if (err) - return err; - memcpy(skb->data - 16, skb->nf_bridge->data, 16); - } - } - return 0; + if (skb->nf_bridge) + return nf_bridge_copy_header(skb); + return 0; } /* This is called by the IP fragmenting code and it ensures there is @@ -90,6 +76,8 @@ struct bridge_skb_cb { }; extern int brnf_deferred_hooks; +#else +#define nf_bridge_maybe_copy_header(skb) (0) #endif /* CONFIG_BRIDGE_NETFILTER */ #endif /* __KERNEL__ */ diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c index 864fbbc7b2..191b861e5e 100644 --- a/net/bridge/br_forward.c +++ b/net/bridge/br_forward.c @@ -38,13 +38,10 @@ int br_dev_queue_push_xmit(struct sk_buff *skb) if (packet_length(skb) > skb->dev->mtu && !skb_is_gso(skb)) kfree_skb(skb); else { -#ifdef CONFIG_BRIDGE_NETFILTER /* ip_refrag calls ip_fragment, doesn't copy the MAC header. */ if (nf_bridge_maybe_copy_header(skb)) kfree_skb(skb); - else -#endif - { + else { skb_push(skb, ETH_HLEN); dev_queue_xmit(skb); diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index 05b3de8882..b498efcfe4 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -127,14 +127,37 @@ static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb) static inline void nf_bridge_save_header(struct sk_buff *skb) { - int header_size = 16; + int header_size = ETH_HLEN; if (skb->protocol == htons(ETH_P_8021Q)) - header_size = 18; + header_size += VLAN_HLEN; memcpy(skb->nf_bridge->data, skb->data - header_size, header_size); } +/* + * When forwarding bridge frames, we save a copy of the original + * header before processing. + */ +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; + + err = skb_cow(skb, header_size); + if (err) + return err; + + memcpy(skb->data - header_size, skb->nf_bridge->data, header_size); + + if (skb->protocol == htons(ETH_P_8021Q)) + __skb_push(skb, VLAN_HLEN); + return 0; +} + /* PF_BRIDGE/PRE_ROUTING *********************************************/ /* Undo the changes made for ip6tables PREROUTING and continue the * bridge PRE_ROUTING hook. */ -- 2.39.5