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 /include | |
| parent | 497574c72c9922cf20c12aed15313c389f722fa0 (diff) | |
| download | lwn-2a7851bffb008ff4882eee673da74718997b4265.tar.gz lwn-2a7851bffb008ff4882eee673da74718997b4265.zip | |
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 'include')
| -rw-r--r-- | include/linux/netfilter_ipv6.h | 16 | ||||
| -rw-r--r-- | include/net/addrconf.h | 2 |
2 files changed, 17 insertions, 1 deletions
diff --git a/include/linux/netfilter_ipv6.h b/include/linux/netfilter_ipv6.h index 98ffb54988b6..2d4df6ce043e 100644 --- a/include/linux/netfilter_ipv6.h +++ b/include/linux/netfilter_ipv6.h @@ -17,6 +17,22 @@ extern __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, extern int ipv6_netfilter_init(void); extern void ipv6_netfilter_fini(void); + +/* + * Hook functions for ipv6 to allow xt_* modules to be built-in even + * if IPv6 is a module. + */ +struct nf_ipv6_ops { + int (*chk_addr)(struct net *net, const struct in6_addr *addr, + const struct net_device *dev, int strict); +}; + +extern const struct nf_ipv6_ops __rcu *nf_ipv6_ops; +static inline const struct nf_ipv6_ops *nf_get_ipv6_ops(void) +{ + return rcu_dereference(nf_ipv6_ops); +} + #else /* CONFIG_NETFILTER */ static inline int ipv6_netfilter_init(void) { return 0; } static inline void ipv6_netfilter_fini(void) { return; } diff --git a/include/net/addrconf.h b/include/net/addrconf.h index 84a6440f1f19..21f702704f24 100644 --- a/include/net/addrconf.h +++ b/include/net/addrconf.h @@ -65,7 +65,7 @@ extern int addrconf_set_dstaddr(struct net *net, extern int ipv6_chk_addr(struct net *net, const struct in6_addr *addr, - struct net_device *dev, + const struct net_device *dev, int strict); #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |