path: root/net/ipv6
diff options
authorLinus Lüssing <linus.luessing@c0d3.blue>2019-01-21 07:26:28 +0100
committerDavid S. Miller <davem@davemloft.net>2019-01-22 17:18:09 -0800
commit4b3087c7e37f9e499127201849e33960dc81da11 (patch)
tree01fb05eabe24132c0fa596c8cf7a536fffda134d /net/ipv6
parent4effd28c1245303dce7fd290c501ac2c11052114 (diff)
bridge: Snoop Multicast Router Advertisements
When multiple multicast routers are present in a broadcast domain then only one of them will be detectable via IGMP/MLD query snooping. The multicast router with the lowest IP address will become the selected and active querier while all other multicast routers will then refrain from sending queries. To detect such rather silent multicast routers, too, RFC4286 ("Multicast Router Discovery") provides a standardized protocol to detect multicast routers for multicast snooping switches. This patch implements the necessary MRD Advertisement message parsing and after successful processing adds such routers to the internal multicast router list. Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
1 files changed, 4 insertions, 1 deletions
diff --git a/net/ipv6/mcast_snoop.c b/net/ipv6/mcast_snoop.c
index a72ddfc40eb3..55e2ac179f28 100644
--- a/net/ipv6/mcast_snoop.c
+++ b/net/ipv6/mcast_snoop.c
@@ -41,6 +41,8 @@ static int ipv6_mc_check_ip6hdr(struct sk_buff *skb)
if (skb->len < len || len <= offset)
return -EINVAL;
+ skb_set_transport_header(skb, offset);
return 0;
@@ -142,7 +144,7 @@ static inline __sum16 ipv6_mc_validate_checksum(struct sk_buff *skb)
return skb_checksum_validate(skb, IPPROTO_ICMPV6, ip6_compute_pseudo);
-static int ipv6_mc_check_icmpv6(struct sk_buff *skb)
+int ipv6_mc_check_icmpv6(struct sk_buff *skb)
unsigned int len = skb_transport_offset(skb) + sizeof(struct icmp6hdr);
unsigned int transport_len = ipv6_transport_len(skb);
@@ -161,6 +163,7 @@ static int ipv6_mc_check_icmpv6(struct sk_buff *skb)
return 0;
* ipv6_mc_check_mld - checks whether this is a sane MLD packet