From 0fae2e7740aca7e384c5f337f458897e7e337d58 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 4 Apr 2011 17:00:54 +0200 Subject: [PATCH] netfilter: af_info: add 'strict' parameter to limit lookup to .oif ipv6 fib lookup can set RT6_LOOKUP_F_IFACE flag to restrict search to an interface, but this flag cannot be set via struct flowi. Also, it cannot be set via ip6_route_output: this function uses the passed sock struct to determine if this flag is required (by testing for nonzero sk_bound_dev_if). Work around this by passing in an artificial struct sk in case 'strict' argument is true. This is required to replace the rt6_lookup call in xt_addrtype.c with nf_afinfo->route(). Signed-off-by: Florian Westphal Acked-by: David S. Miller Signed-off-by: Patrick McHardy --- include/linux/netfilter.h | 2 +- net/ipv4/netfilter.c | 2 +- net/ipv6/netfilter.c | 12 ++++++++++-- net/netfilter/nf_conntrack_h323_main.c | 8 ++++---- net/netfilter/xt_TCPMSS.c | 2 +- 5 files changed, 17 insertions(+), 9 deletions(-) diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index 20ed452..7fa95df 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -271,7 +271,7 @@ struct nf_afinfo { unsigned int len, u_int8_t protocol); int (*route)(struct net *net, struct dst_entry **dst, - struct flowi *fl); + struct flowi *fl, bool strict); void (*saveroute)(const struct sk_buff *skb, struct nf_queue_entry *entry); int (*reroute)(struct sk_buff *skb, diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c index f1035f056..4614bab 100644 --- a/net/ipv4/netfilter.c +++ b/net/ipv4/netfilter.c @@ -222,7 +222,7 @@ static __sum16 nf_ip_checksum_partial(struct sk_buff *skb, unsigned int hook, } static int nf_ip_route(struct net *net, struct dst_entry **dst, - struct flowi *fl) + struct flowi *fl, bool strict __always_unused) { struct rtable *rt = ip_route_output_key(net, &fl->u.ip4); if (IS_ERR(rt)) diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c index e008b9b..28bc1f6 100644 --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -91,9 +91,17 @@ static int nf_ip6_reroute(struct sk_buff *skb, } static int nf_ip6_route(struct net *net, struct dst_entry **dst, - struct flowi *fl) + struct flowi *fl, bool strict) { - *dst = ip6_route_output(net, NULL, &fl->u.ip6); + static const struct ipv6_pinfo fake_pinfo; + static const struct inet_sock fake_sk = { + /* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */ + .sk.sk_bound_dev_if = 1, + .pinet6 = (struct ipv6_pinfo *) &fake_pinfo, + }; + const void *sk = strict ? &fake_sk : NULL; + + *dst = ip6_route_output(net, sk, &fl->u.ip6); return (*dst)->error; } diff --git a/net/netfilter/nf_conntrack_h323_main.c b/net/netfilter/nf_conntrack_h323_main.c index 39a4538..18b2ce5 100644 --- a/net/netfilter/nf_conntrack_h323_main.c +++ b/net/netfilter/nf_conntrack_h323_main.c @@ -732,9 +732,9 @@ static int callforward_do_filter(const union nf_inet_addr *src, memset(&fl2, 0, sizeof(fl2)); fl2.daddr = dst->ip; if (!afinfo->route(&init_net, (struct dst_entry **)&rt1, - flowi4_to_flowi(&fl1))) { + flowi4_to_flowi(&fl1), false)) { if (!afinfo->route(&init_net, (struct dst_entry **)&rt2, - flowi4_to_flowi(&fl2))) { + flowi4_to_flowi(&fl2), false)) { if (rt1->rt_gateway == rt2->rt_gateway && rt1->dst.dev == rt2->dst.dev) ret = 1; @@ -756,9 +756,9 @@ static int callforward_do_filter(const union nf_inet_addr *src, memset(&fl2, 0, sizeof(fl2)); ipv6_addr_copy(&fl2.daddr, &dst->in6); if (!afinfo->route(&init_net, (struct dst_entry **)&rt1, - flowi6_to_flowi(&fl1))) { + flowi6_to_flowi(&fl1), false)) { if (!afinfo->route(&init_net, (struct dst_entry **)&rt2, - flowi6_to_flowi(&fl2))) { + flowi6_to_flowi(&fl2), false)) { if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway, sizeof(rt1->rt6i_gateway)) && rt1->dst.dev == rt2->dst.dev) diff --git a/net/netfilter/xt_TCPMSS.c b/net/netfilter/xt_TCPMSS.c index 8690125..9e63b43 100644 --- a/net/netfilter/xt_TCPMSS.c +++ b/net/netfilter/xt_TCPMSS.c @@ -166,7 +166,7 @@ static u_int32_t tcpmss_reverse_mtu(const struct sk_buff *skb, rcu_read_lock(); ai = nf_get_afinfo(family); if (ai != NULL) - ai->route(&init_net, (struct dst_entry **)&rt, &fl); + ai->route(&init_net, (struct dst_entry **)&rt, &fl, false); rcu_read_unlock(); if (rt != NULL) { -- 2.7.4