From 72b1e5e4cac72efa6b739b47e41f53e4520b4194 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 23 Jul 2015 16:21:30 +0200 Subject: [PATCH] netfilter: bridge: reduce nf_bridge_info to 32 bytes again We can use union for most of the temporary cruft (original ipv4/ipv6 address, source mac, physoutdev) since they're used during different stages of br netfilter traversal. Also get rid of the last two ->mask users. Shrinks struct from 48 to 32 on 64bit arch. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- include/linux/netfilter_bridge.h | 12 +++++++++--- include/linux/skbuff.h | 19 +++++++++++++------ net/bridge/br_netfilter_hooks.c | 14 ++++++-------- net/bridge/br_netfilter_ipv6.c | 2 +- net/ipv4/netfilter/nf_defrag_ipv4.c | 7 ++----- net/ipv6/netfilter/nf_defrag_ipv6_hooks.c | 7 ++----- 6 files changed, 33 insertions(+), 28 deletions(-) diff --git a/include/linux/netfilter_bridge.h b/include/linux/netfilter_bridge.h index 6d80fc686323..2437b8a5d7a9 100644 --- a/include/linux/netfilter_bridge.h +++ b/include/linux/netfilter_bridge.h @@ -17,9 +17,6 @@ enum nf_br_hook_priorities { #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) -#define BRNF_BRIDGED_DNAT 0x02 -#define BRNF_NF_BRIDGE_PREROUTING 0x08 - int br_handle_frame_finish(struct sock *sk, struct sk_buff *skb); static inline void br_drop_fake_rtable(struct sk_buff *skb) @@ -63,8 +60,17 @@ nf_bridge_get_physoutdev(const struct sk_buff *skb) { return skb->nf_bridge ? skb->nf_bridge->physoutdev : NULL; } + +static inline bool nf_bridge_in_prerouting(const struct sk_buff *skb) +{ + return skb->nf_bridge && skb->nf_bridge->in_prerouting; +} #else #define br_drop_fake_rtable(skb) do { } while (0) +static inline bool nf_bridge_in_prerouting(const struct sk_buff *skb) +{ + return false; +} #endif /* CONFIG_BRIDGE_NETFILTER */ #endif diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index d6cdd6e87d53..ac732e67a6c8 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -173,17 +173,24 @@ struct nf_bridge_info { BRNF_PROTO_8021Q, BRNF_PROTO_PPPOE } orig_proto:8; - bool pkt_otherhost; + u8 pkt_otherhost:1; + u8 in_prerouting:1; + u8 bridged_dnat:1; __u16 frag_max_size; - unsigned int mask; struct net_device *physindev; union { - struct net_device *physoutdev; - char neigh_header[8]; - }; - union { + /* prerouting: detect dnat in orig/reply direction */ __be32 ipv4_daddr; struct in6_addr ipv6_daddr; + + /* after prerouting + nat detected: store original source + * mac since neigh resolution overwrites it, only used while + * skb is out in neigh layer. + */ + char neigh_header[8]; + + /* always valid & non-NULL from FORWARD on, for physdev match */ + struct net_device *physoutdev; }; }; #endif diff --git a/net/bridge/br_netfilter_hooks.c b/net/bridge/br_netfilter_hooks.c index c8b9bcfe997e..ec51c2ba30e9 100644 --- a/net/bridge/br_netfilter_hooks.c +++ b/net/bridge/br_netfilter_hooks.c @@ -284,7 +284,7 @@ int br_nf_pre_routing_finish_bridge(struct sock *sk, struct sk_buff *skb) nf_bridge->neigh_header, ETH_HLEN-ETH_ALEN); /* tell br_dev_xmit to continue with forwarding */ - nf_bridge->mask |= BRNF_BRIDGED_DNAT; + nf_bridge->bridged_dnat = 1; /* FIXME Need to refragment */ ret = neigh->output(neigh, skb); } @@ -356,7 +356,7 @@ static int br_nf_pre_routing_finish(struct sock *sk, struct sk_buff *skb) skb->pkt_type = PACKET_OTHERHOST; nf_bridge->pkt_otherhost = false; } - nf_bridge->mask &= ~BRNF_NF_BRIDGE_PREROUTING; + nf_bridge->in_prerouting = 0; if (br_nf_ipv4_daddr_was_changed(skb, nf_bridge)) { if ((err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev))) { struct in_device *in_dev = __in_dev_get_rcu(dev); @@ -444,7 +444,7 @@ struct net_device *setup_pre_routing(struct sk_buff *skb) nf_bridge->pkt_otherhost = true; } - nf_bridge->mask |= BRNF_NF_BRIDGE_PREROUTING; + nf_bridge->in_prerouting = 1; nf_bridge->physindev = skb->dev; skb->dev = brnf_get_logical_dev(skb, skb->dev); @@ -850,10 +850,8 @@ static unsigned int ip_sabotage_in(const struct nf_hook_ops *ops, struct sk_buff *skb, const struct nf_hook_state *state) { - if (skb->nf_bridge && - !(skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)) { + if (skb->nf_bridge && !skb->nf_bridge->in_prerouting) return NF_STOP; - } return NF_ACCEPT; } @@ -872,7 +870,7 @@ static void br_nf_pre_routing_finish_bridge_slow(struct sk_buff *skb) struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb); skb_pull(skb, ETH_HLEN); - nf_bridge->mask &= ~BRNF_BRIDGED_DNAT; + nf_bridge->bridged_dnat = 0; BUILD_BUG_ON(sizeof(nf_bridge->neigh_header) != (ETH_HLEN - ETH_ALEN)); @@ -887,7 +885,7 @@ static void br_nf_pre_routing_finish_bridge_slow(struct sk_buff *skb) static int br_nf_dev_xmit(struct sk_buff *skb) { - if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) { + if (skb->nf_bridge && skb->nf_bridge->bridged_dnat) { br_nf_pre_routing_finish_bridge_slow(skb); return 1; } diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c index 13b7d1e3d185..77383bfe7ea3 100644 --- a/net/bridge/br_netfilter_ipv6.c +++ b/net/bridge/br_netfilter_ipv6.c @@ -174,7 +174,7 @@ static int br_nf_pre_routing_finish_ipv6(struct sock *sk, struct sk_buff *skb) skb->pkt_type = PACKET_OTHERHOST; nf_bridge->pkt_otherhost = false; } - nf_bridge->mask &= ~BRNF_NF_BRIDGE_PREROUTING; + nf_bridge->in_prerouting = 0; if (br_nf_ipv6_daddr_was_changed(skb, nf_bridge)) { skb_dst_drop(skb); v6ops->route_input(skb); diff --git a/net/ipv4/netfilter/nf_defrag_ipv4.c b/net/ipv4/netfilter/nf_defrag_ipv4.c index c88b7d434718..b69e82bda215 100644 --- a/net/ipv4/netfilter/nf_defrag_ipv4.c +++ b/net/ipv4/netfilter/nf_defrag_ipv4.c @@ -49,12 +49,9 @@ static enum ip_defrag_users nf_ct_defrag_user(unsigned int hooknum, if (skb->nfct) zone = nf_ct_zone((struct nf_conn *)skb->nfct); #endif - -#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - if (skb->nf_bridge && - skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING) + if (nf_bridge_in_prerouting(skb)) return IP_DEFRAG_CONNTRACK_BRIDGE_IN + zone; -#endif + if (hooknum == NF_INET_PRE_ROUTING) return IP_DEFRAG_CONNTRACK_IN + zone; else diff --git a/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c b/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c index a45db0b4785c..267fb8d5876e 100644 --- a/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c +++ b/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c @@ -39,12 +39,9 @@ static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum, if (skb->nfct) zone = nf_ct_zone((struct nf_conn *)skb->nfct); #endif - -#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - if (skb->nf_bridge && - skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING) + if (nf_bridge_in_prerouting(skb)) return IP6_DEFRAG_CONNTRACK_BRIDGE_IN + zone; -#endif + if (hooknum == NF_INET_PRE_ROUTING) return IP6_DEFRAG_CONNTRACK_IN + zone; else -- GitLab