From mboxrd@z Thu Jan 1 00:00:00 1970 From: shemminger@osdl.org Subject: [PATCH 2/4] bridge-netfilter: code rearrangement for clarity Date: Tue, 22 Aug 2006 17:10:52 -0700 Message-ID: <20060823001230.935359000@localhost.localdomain> References: <20060823001050.363374000@localhost.localdomain> Cc: netdev@vger.kernel.org Return-path: Received: from smtp.osdl.org ([65.172.181.4]:38878 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1751072AbWHWATX (ORCPT ); Tue, 22 Aug 2006 20:19:23 -0400 To: David Miller Content-Disposition: inline; filename=br-nf-reorg.patch Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org 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 --- br-nf.orig/include/linux/netfilter_bridge.h 2006-08-22 16:45:05.000000000 -0700 +++ br-nf/include/linux/netfilter_bridge.h 2006-08-22 16:46:47.000000000 -0700 @@ -47,26 +47,12 @@ /* 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 @@ }; extern int brnf_deferred_hooks; +#else +#define nf_bridge_maybe_copy_header(skb) (0) #endif /* CONFIG_BRIDGE_NETFILTER */ #endif /* __KERNEL__ */ --- br-nf.orig/net/bridge/br_forward.c 2006-08-22 16:44:04.000000000 -0700 +++ br-nf/net/bridge/br_forward.c 2006-08-22 16:48:12.000000000 -0700 @@ -38,13 +38,10 @@ 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); --- br-nf.orig/net/bridge/br_netfilter.c 2006-08-22 16:44:04.000000000 -0700 +++ br-nf/net/bridge/br_netfilter.c 2006-08-22 16:48:56.000000000 -0700 @@ -127,14 +127,37 @@ 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. */ --