From c68cd6cc21eb329c47ff020ff7412bf58176984e Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Thu, 17 Jun 2010 06:12:26 +0200 Subject: netfilter: nf_nat: support user-specified SNAT rules in LOCAL_IN 2.6.34 introduced 'conntrack zones' to deal with cases where packets from multiple identical networks are handled by conntrack/NAT. Packets are looped through veth devices, during which they are NATed to private addresses, after which they can continue normally through the stack and possibly have NAT rules applied a second time. This works well, but is needlessly complicated for cases where only a single SNAT/DNAT mapping needs to be applied to these packets. In that case, all that needs to be done is to assign each network to a seperate zone and perform NAT as usual. However this doesn't work for packets destined for the machine performing NAT itself since its corrently not possible to configure SNAT mappings for the LOCAL_IN chain. This patch adds a new INPUT chain to the NAT table and changes the targets performing SNAT to be usable in that chain. Example usage with two identical networks (192.168.0.0/24) on eth0/eth1: iptables -t raw -A PREROUTING -i eth0 -j CT --zone 1 iptables -t raw -A PREROUTING -i eth0 -j MARK --set-mark 1 iptables -t raw -A PREROUTING -i eth1 -j CT --zone 2 iptabels -t raw -A PREROUTING -i eth1 -j MARK --set-mark 2 iptables -t nat -A INPUT -m mark --mark 1 -j NETMAP --to 10.0.0.0/24 iptables -t nat -A POSTROUTING -m mark --mark 1 -j NETMAP --to 10.0.0.0/24 iptables -t nat -A INPUT -m mark --mark 2 -j NETMAP --to 10.0.1.0/24 iptables -t nat -A POSTROUTING -m mark --mark 2 -j NETMAP --to 10.0.1.0/24 iptables -t raw -A PREROUTING -d 10.0.0.0/24 -j CT --zone 1 iptables -t raw -A OUTPUT -d 10.0.0.0/24 -j CT --zone 1 iptables -t raw -A PREROUTING -d 10.0.1.0/24 -j CT --zone 2 iptables -t raw -A OUTPUT -d 10.0.1.0/24 -j CT --zone 2 iptables -t nat -A PREROUTING -d 10.0.0.0/24 -j NETMAP --to 192.168.0.0/24 iptables -t nat -A OUTPUT -d 10.0.0.0/24 -j NETMAP --to 192.168.0.0/24 iptables -t nat -A PREROUTING -d 10.0.1.0/24 -j NETMAP --to 192.168.0.0/24 iptables -t nat -A OUTPUT -d 10.0.1.0/24 -j NETMAP --to 192.168.0.0/24 Signed-off-by: Patrick McHardy --- include/net/netfilter/nf_nat_rule.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include/net') diff --git a/include/net/netfilter/nf_nat_rule.h b/include/net/netfilter/nf_nat_rule.h index e4a18ae..2890bdc 100644 --- a/include/net/netfilter/nf_nat_rule.h +++ b/include/net/netfilter/nf_nat_rule.h @@ -12,6 +12,4 @@ extern int nf_nat_rule_find(struct sk_buff *skb, const struct net_device *out, struct nf_conn *ct); -extern unsigned int -alloc_null_binding(struct nf_conn *ct, unsigned int hooknum); #endif /* _NF_NAT_RULE_H */ -- cgit v1.1 From a8756201ba4189bca3ee1a6ec4e290f467ee09ab Mon Sep 17 00:00:00 2001 From: Tim Gardner Date: Fri, 25 Jun 2010 14:44:07 +0200 Subject: netfilter: xt_connbytes: Force CT accounting to be enabled Check at rule install time that CT accounting is enabled. Force it to be enabled if not while also emitting a warning since this is not the default state. This is in preparation for deprecating CONFIG_NF_CT_ACCT upon which CONFIG_NETFILTER_XT_MATCH_CONNBYTES depended being set. Added 2 CT accounting support functions: nf_ct_acct_enabled() - Get CT accounting state. nf_ct_set_acct() - Enable/disable CT accountuing. Signed-off-by: Tim Gardner Acked-by: Jan Engelhardt Signed-off-by: Patrick McHardy --- include/net/netfilter/nf_conntrack_acct.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/net') diff --git a/include/net/netfilter/nf_conntrack_acct.h b/include/net/netfilter/nf_conntrack_acct.h index 03e218f..4e9c63a 100644 --- a/include/net/netfilter/nf_conntrack_acct.h +++ b/include/net/netfilter/nf_conntrack_acct.h @@ -45,6 +45,18 @@ struct nf_conn_counter *nf_ct_acct_ext_add(struct nf_conn *ct, gfp_t gfp) extern unsigned int seq_print_acct(struct seq_file *s, const struct nf_conn *ct, int dir); +/* Check if connection tracking accounting is enabled */ +static inline bool nf_ct_acct_enabled(struct net *net) +{ + return net->ct.sysctl_acct != 0; +} + +/* Enable/disable connection tracking accounting */ +static inline void nf_ct_set_acct(struct net *net, bool enable) +{ + net->ct.sysctl_acct = enable; +} + extern int nf_conntrack_acct_init(struct net *net); extern void nf_conntrack_acct_fini(struct net *net); -- cgit v1.1