From 0131261ac3947631b96036ffafb30ee2e95604f2 Mon Sep 17 00:00:00 2001
From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Date: Thu, 30 Aug 2012 07:07:30 -0400
Subject: [PATCH] ipv6: fix handling of blackhole and prohibit routes
When adding a blackhole or a prohibit route, they were handling like classic
routes. Moreover, it was only possible to add this kind of routes by specifying
an interface.
Bug already reported here:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=498498
Before the patch:
$ ip route add blackhole 2001::1/128
RTNETLINK answers: No such device
$ ip route add blackhole 2001::1/128 dev eth0
$ ip -6 route | grep 2001
2001::1 dev eth0 metric 1024
After:
$ ip route add blackhole 2001::1/128
$ ip -6 route | grep 2001
blackhole 2001::1 dev lo metric 1024 error -22
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
---
include/linux/route.h | 2 ++
net/ipv6/route.c | 27 ++++++++++++++++++++++-----
2 files changed, 24 insertions(+), 5 deletions(-)
@@ -58,6 +58,8 @@ struct rtentry {
#define RTF_WINDOW 0x0080 /* per route window clamping */
#define RTF_IRTT 0x0100 /* Initial round trip time */
#define RTF_REJECT 0x0200 /* Reject route */
+#define RTF_BLACKHOLE 0x0400 /* Blackhole route */
+#define RTF_PROHIBIT 0x0800 /* Prohibit route */
/*
* <linux/ipv6_route.h> uses RTF values >= 64k
@@ -251,7 +251,7 @@ static struct rt6_info ip6_prohibit_entry_template = {
.input = ip6_pkt_prohibit,
.output = ip6_pkt_prohibit_out,
},
- .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
+ .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP | RTF_PROHIBIT),
.rt6i_protocol = RTPROT_KERNEL,
.rt6i_metric = ~(u32) 0,
.rt6i_ref = ATOMIC_INIT(1),
@@ -266,7 +266,7 @@ static struct rt6_info ip6_blk_hole_entry_template = {
.input = dst_discard,
.output = dst_discard,
},
- .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
+ .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP | RTF_BLACKHOLE),
.rt6i_protocol = RTPROT_KERNEL,
.rt6i_metric = ~(u32) 0,
.rt6i_ref = ATOMIC_INIT(1),
@@ -1463,8 +1463,15 @@ int ip6_route_add(struct fib6_config *cfg)
}
rt->dst.output = ip6_pkt_discard_out;
rt->dst.input = ip6_pkt_discard;
- rt->dst.error = -ENETUNREACH;
rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
+ if (cfg->fc_flags & RTF_BLACKHOLE) {
+ rt->dst.error = -EINVAL;
+ rt->rt6i_flags |= RTF_BLACKHOLE;
+ } else if (cfg->fc_flags & RTF_PROHIBIT) {
+ rt->dst.error = -EACCES;
+ rt->rt6i_flags |= RTF_PROHIBIT;
+ } else
+ rt->dst.error = -ENETUNREACH;
goto install_route;
}
@@ -2264,6 +2271,10 @@ static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
if (rtm->rtm_type == RTN_UNREACHABLE)
cfg->fc_flags |= RTF_REJECT;
+ if (rtm->rtm_type == RTN_BLACKHOLE)
+ cfg->fc_flags |= RTF_REJECT | RTF_BLACKHOLE;
+ if (rtm->rtm_type == RTN_PROHIBIT)
+ cfg->fc_flags |= RTF_REJECT | RTF_PROHIBIT;
if (rtm->rtm_type == RTN_LOCAL)
cfg->fc_flags |= RTF_LOCAL;
@@ -2391,8 +2402,14 @@ static int rt6_fill_node(struct net *net,
rtm->rtm_table = table;
if (nla_put_u32(skb, RTA_TABLE, table))
goto nla_put_failure;
- if (rt->rt6i_flags & RTF_REJECT)
- rtm->rtm_type = RTN_UNREACHABLE;
+ if (rt->rt6i_flags & RTF_REJECT) {
+ if (rt->rt6i_flags & RTF_BLACKHOLE)
+ rtm->rtm_type = RTN_BLACKHOLE;
+ else if (rt->rt6i_flags & RTF_PROHIBIT)
+ rtm->rtm_type = RTN_PROHIBIT;
+ else
+ rtm->rtm_type = RTN_UNREACHABLE;
+ }
else if (rt->rt6i_flags & RTF_LOCAL)
rtm->rtm_type = RTN_LOCAL;
else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
--
1.7.10.4