From a3e520f37b084fe759da16f367f6a32f6f7e42a8 Mon Sep 17 00:00:00 2001 From: Philippe Guibert Date: Thu, 30 Jul 2020 18:16:16 +0200 Subject: [PATCH] nhrpd: replace nhrp route nexthop with onlink route when prefix=nh There are cases where nhrp wants to create a nhrp route to gre interface with the nexthop which is the same the prefix. This is the case with ipv6: ipv6 route a:ff::ff:4/128 via a:ff::ff:4:/128 dev gre1 This route entry is false from zebra point of view, and to avoid that, the nexthop is ignored in nhrp only if the prefix equals the nexthop. Signed-off-by: Philippe Guibert --- nhrpd/nhrp_route.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/nhrpd/nhrp_route.c b/nhrpd/nhrp_route.c index ce2b1fe2ff..334f468c18 100755 --- a/nhrpd/nhrp_route.c +++ b/nhrpd/nhrp_route.c @@ -98,6 +98,7 @@ void nhrp_route_announce(int add, enum nhrp_cache_type type, { struct zapi_route api; struct zapi_nexthop *api_nh; + union sockunion *nexthop_ref = (union sockunion *)nexthop; if (zclient->sock < 0) return; @@ -133,8 +134,14 @@ void nhrp_route_announce(int add, enum nhrp_cache_type type, switch (api.prefix.family) { case AF_INET: - if (nexthop) { - api_nh->gate.ipv4 = nexthop->sin.sin_addr; + if (api.prefix.prefixlen == IPV4_MAX_BITLEN && + nexthop_ref && + memcmp(&nexthop_ref->sin.sin_addr, &api.prefix.u.prefix4, + sizeof(struct in_addr)) == 0) { + nexthop_ref = NULL; + } + if (nexthop_ref) { + api_nh->gate.ipv4 = nexthop_ref->sin.sin_addr; api_nh->type = NEXTHOP_TYPE_IPV4; } if (ifp) { @@ -146,8 +153,14 @@ void nhrp_route_announce(int add, enum nhrp_cache_type type, } break; case AF_INET6: - if (nexthop) { - api_nh->gate.ipv6 = nexthop->sin6.sin6_addr; + if (api.prefix.prefixlen == IPV6_MAX_BITLEN && + nexthop_ref && + memcmp(&nexthop_ref->sin6.sin6_addr, &api.prefix.u.prefix6, + sizeof(struct in6_addr)) == 0) { + nexthop_ref = NULL; + } + if (nexthop_ref) { + api_nh->gate.ipv6 = nexthop_ref->sin6.sin6_addr; api_nh->type = NEXTHOP_TYPE_IPV6; } if (ifp) { @@ -170,8 +183,9 @@ void nhrp_route_announce(int add, enum nhrp_cache_type type, zlog_debug( "Zebra send: route %s %pFX nexthop %s metric %u count %d dev %s", add ? "add" : "del", &api.prefix, - nexthop ? inet_ntop(api.prefix.family, &api_nh->gate, - buf, sizeof(buf)) + nexthop_ref ? inet_ntop(api.prefix.family, + &api_nh->gate, + buf, sizeof(buf)) : "", api.metric, api.nexthop_num, ifp ? ifp->name : "none"); } -- 2.39.5