From eb9c7ebe6980c41cf6ae889e301c3b49f473ee9f Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Fri, 6 Jan 2006 23:06:30 -0800 Subject: [NETFILTER]: Handle NAT in IPsec policy checks Handle NAT of decapsulated IPsec packets by reconstructing the struct flowi of the original packet from the conntrack information for IPsec policy checks. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/ipv4/netfilter/ip_nat_standalone.c | 50 ++++++++++++++++++++++++++++++++-- 1 file changed, 48 insertions(+), 2 deletions(-) (limited to 'net/ipv4/netfilter') diff --git a/net/ipv4/netfilter/ip_nat_standalone.c b/net/ipv4/netfilter/ip_nat_standalone.c index b518697af4d..8b8a1f00bbf 100644 --- a/net/ipv4/netfilter/ip_nat_standalone.c +++ b/net/ipv4/netfilter/ip_nat_standalone.c @@ -55,6 +55,44 @@ : ((hooknum) == NF_IP_LOCAL_IN ? "LOCAL_IN" \ : "*ERROR*"))) +#ifdef CONFIG_XFRM +static void nat_decode_session(struct sk_buff *skb, struct flowi *fl) +{ + struct ip_conntrack *ct; + struct ip_conntrack_tuple *t; + enum ip_conntrack_info ctinfo; + enum ip_conntrack_dir dir; + unsigned long statusbit; + + ct = ip_conntrack_get(skb, &ctinfo); + if (ct == NULL) + return; + dir = CTINFO2DIR(ctinfo); + t = &ct->tuplehash[dir].tuple; + + if (dir == IP_CT_DIR_ORIGINAL) + statusbit = IPS_DST_NAT; + else + statusbit = IPS_SRC_NAT; + + if (ct->status & statusbit) { + fl->fl4_dst = t->dst.ip; + if (t->dst.protonum == IPPROTO_TCP || + t->dst.protonum == IPPROTO_UDP) + fl->fl_ip_dport = t->dst.u.tcp.port; + } + + statusbit ^= IPS_NAT_MASK; + + if (ct->status & statusbit) { + fl->fl4_src = t->src.ip; + if (t->dst.protonum == IPPROTO_TCP || + t->dst.protonum == IPPROTO_UDP) + fl->fl_ip_sport = t->src.u.tcp.port; + } +} +#endif + static unsigned int ip_nat_fn(unsigned int hooknum, struct sk_buff **pskb, @@ -330,10 +368,14 @@ static int init_or_cleanup(int init) if (!init) goto cleanup; +#ifdef CONFIG_XFRM + BUG_ON(ip_nat_decode_session != NULL); + ip_nat_decode_session = nat_decode_session; +#endif ret = ip_nat_rule_init(); if (ret < 0) { printk("ip_nat_init: can't setup rules.\n"); - goto cleanup_nothing; + goto cleanup_decode_session; } ret = nf_register_hook(&ip_nat_in_ops); if (ret < 0) { @@ -381,7 +423,11 @@ static int init_or_cleanup(int init) nf_unregister_hook(&ip_nat_in_ops); cleanup_rule_init: ip_nat_rule_cleanup(); - cleanup_nothing: + cleanup_decode_session: +#ifdef CONFIG_XFRM + ip_nat_decode_session = NULL; + synchronize_net(); +#endif return ret; } -- cgit v1.2.3