netfilter: conntrack: set icmpv6 redirects as RELATED

[ Upstream commit 7d7cfb48d81353e826493d24c7cec7360950968f ]

icmp conntrack will set icmp redirects as RELATED, but icmpv6 will not
do this.

For icmpv6, only icmp errors (code <= 128) are examined for RELATED state.
ICMPV6 Redirects are part of neighbour discovery mechanism, those are
handled by marking a selected subset (e.g.  neighbour solicitations) as
UNTRACKED, but not REDIRECT -- they will thus be flagged as INVALID.

Add minimal support for REDIRECTs.  No parsing of neighbour options is
added for simplicity, so this will only check that we have the embeeded
original header (ND_OPT_REDIRECT_HDR), and then attempt to do a flow
lookup for this tuple.

Also extend the existing test case to cover redirects.

Fixes: 9fb9cbb1082d ("[NETFILTER]: Add nf_conntrack subsystem.")
Reported-by: Eric Garver <eric@garver.life>
Link: https://github.com/firewalld/firewalld/issues/1046
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Garver <eric@garver.life>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

1 files changed, 34 insertions, 2 deletions

diff --git a/tools/testing/selftests/netfilter/conntrack_icmp_related.sh b/tools/testing/selftests/netfilter/conntrack_icmp_related.sh
index b48e1833bc89..76645aaf2b58 100755
--- a/tools/testing/selftests/netfilter/conntrack_icmp_related.sh
+++ b/tools/testing/selftests/netfilter/conntrack_icmp_related.sh
@@ -35,6 +35,8 @@ cleanup() {
 	for i in 1 2;do ip netns del nsrouter$i;done
 }
 
+trap cleanup EXIT
+
 ipv4() {
     echo -n 192.168.$1.2
 }
@@ -146,11 +148,17 @@ ip netns exec nsclient1 nft -f - <<EOF
 table inet filter {
 	counter unknown { }
 	counter related { }
+	counter redir4 { }
+	counter redir6 { }
 	chain input {
 		type filter hook input priority 0; policy accept;
-		meta l4proto { icmp, icmpv6 } ct state established,untracked accept
 
+		icmp type "redirect" ct state "related" counter name "redir4" accept
+		icmpv6 type "nd-redirect" ct state "related" counter name "redir6" accept
+
+		meta l4proto { icmp, icmpv6 } ct state established,untracked accept
 		meta l4proto { icmp, icmpv6 } ct state "related" counter name "related" accept
+
 		counter name "unknown" drop
 	}
 }
@@ -279,5 +287,29 @@ else
 	echo "ERROR: icmp error RELATED state test has failed"
 fi
 
-cleanup
+# add 'bad' route,  expect icmp REDIRECT to be generated
+ip netns exec nsclient1 ip route add 192.168.1.42 via 192.168.1.1
+ip netns exec nsclient1 ip route add dead:1::42 via dead:1::1
+
+ip netns exec "nsclient1" ping -q -c 2 192.168.1.42 > /dev/null
+
+expect="packets 1 bytes 112"
+check_counter nsclient1 "redir4" "$expect"
+if [ $? -ne 0 ];then
+	ret=1
+fi
+
+ip netns exec "nsclient1" ping -c 1 dead:1::42 > /dev/null
+expect="packets 1 bytes 192"
+check_counter nsclient1 "redir6" "$expect"
+if [ $? -ne 0 ];then
+	ret=1
+fi
+
+if [ $ret -eq 0 ];then
+	echo "PASS: icmp redirects had RELATED state"
+else
+	echo "ERROR: icmp redirect RELATED state test has failed"
+fi
+
 exit $ret