diff options
author | Florian Westphal <fw@strlen.de> | 2013-05-17 03:56:10 +0000 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2013-05-23 11:58:55 +0200 |
commit | 2a7851bffb008ff4882eee673da74718997b4265 (patch) | |
tree | 262c2fc71bd91eabf6bd947944d2050ff1cec923 /net/netfilter/xt_addrtype.c | |
parent | 497574c72c9922cf20c12aed15313c389f722fa0 (diff) | |
download | op-kernel-dev-2a7851bffb008ff4882eee673da74718997b4265.zip op-kernel-dev-2a7851bffb008ff4882eee673da74718997b4265.tar.gz |
netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6
Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812:
[ ip6tables -m addrtype ]
When I tried to use in the nat/PREROUTING it messes up the
routing cache even if the rule didn't matched at all.
[..]
If I remove the --limit-iface-in from the non-working scenario, so just
use the -m addrtype --dst-type LOCAL it works!
This happens when LOCAL type matching is requested with --limit-iface-in,
and the default ipv6 route is via the interface the packet we test
arrived on.
Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation
creates an unwanted cached entry, and the packet won't make it to the
real/expected destination.
Silently ignoring --limit-iface-in makes the routing work but it breaks
rule matching (--dst-type LOCAL with limit-iface-in is supposed to only
match if the dst address is configured on the incoming interface;
without --limit-iface-in it will match if the address is reachable
via lo).
The test should call ipv6_chk_addr() instead. However, this would add
a link-time dependency on ipv6.
There are two possible solutions:
1) Revert the commit that moved ipt_addrtype to xt_addrtype,
and put ipv6 specific code into ip6t_addrtype.
2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions.
While the former might seem preferable, Pablo pointed out that there
are more xt modules with link-time dependeny issues regarding ipv6,
so lets go for 2).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/xt_addrtype.c')
-rw-r--r-- | net/netfilter/xt_addrtype.c | 27 |
1 files changed, 16 insertions, 11 deletions
diff --git a/net/netfilter/xt_addrtype.c b/net/netfilter/xt_addrtype.c index 49c5ff7..68ff29f 100644 --- a/net/netfilter/xt_addrtype.c +++ b/net/netfilter/xt_addrtype.c @@ -22,6 +22,7 @@ #include <net/ip6_fib.h> #endif +#include <linux/netfilter_ipv6.h> #include <linux/netfilter/xt_addrtype.h> #include <linux/netfilter/x_tables.h> @@ -33,12 +34,12 @@ MODULE_ALIAS("ip6t_addrtype"); #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) static u32 match_lookup_rt6(struct net *net, const struct net_device *dev, - const struct in6_addr *addr) + const struct in6_addr *addr, u16 mask) { const struct nf_afinfo *afinfo; struct flowi6 flow; struct rt6_info *rt; - u32 ret; + u32 ret = 0; int route_err; memset(&flow, 0, sizeof(flow)); @@ -49,12 +50,19 @@ static u32 match_lookup_rt6(struct net *net, const struct net_device *dev, rcu_read_lock(); afinfo = nf_get_afinfo(NFPROTO_IPV6); - if (afinfo != NULL) + if (afinfo != NULL) { + const struct nf_ipv6_ops *v6ops; + + if (dev && (mask & XT_ADDRTYPE_LOCAL)) { + v6ops = nf_get_ipv6_ops(); + if (v6ops && v6ops->chk_addr(net, addr, dev, true)) + ret = XT_ADDRTYPE_LOCAL; + } route_err = afinfo->route(net, (struct dst_entry **)&rt, - flowi6_to_flowi(&flow), !!dev); - else + flowi6_to_flowi(&flow), false); + } else { route_err = 1; - + } rcu_read_unlock(); if (route_err) @@ -62,15 +70,12 @@ static u32 match_lookup_rt6(struct net *net, const struct net_device *dev, if (rt->rt6i_flags & RTF_REJECT) ret = XT_ADDRTYPE_UNREACHABLE; - else - ret = 0; - if (rt->rt6i_flags & RTF_LOCAL) + if (dev == NULL && rt->rt6i_flags & RTF_LOCAL) ret |= XT_ADDRTYPE_LOCAL; if (rt->rt6i_flags & RTF_ANYCAST) ret |= XT_ADDRTYPE_ANYCAST; - dst_release(&rt->dst); return ret; } @@ -90,7 +95,7 @@ static bool match_type6(struct net *net, const struct net_device *dev, if ((XT_ADDRTYPE_LOCAL | XT_ADDRTYPE_ANYCAST | XT_ADDRTYPE_UNREACHABLE) & mask) - return !!(mask & match_lookup_rt6(net, dev, addr)); + return !!(mask & match_lookup_rt6(net, dev, addr, mask)); return true; } |