IPv6 transport class suppport

IPv6 supports the same concept of differentiated service for routing
protocols as IPv4, but like too many things, the standards committee
decided that having two names for the same thing wasn't good enough and
introduced a third more generic term transport class.

The socket option to set transport class works the same as IPv4, but the
arguments are different.

* lib/sockopt.[ch]
  * setsockopt_ipv6_tclass(): new function
* bgpd/bgp_network.c
  * bgp_connect(): set socket option
  * bgp_listener(): set socket option
* ospf6d/ospf6_network.c
  * ospf6_set_transport_class(): new function
  * ospf6_serv_sock(): set socket option
* ripngd/ripngd.c
  * ripng_make_socket(): set socket option

1 files changed, 12 insertions, 1 deletions

diff --git a/lib/sockopt.c b/lib/sockopt.c
index 9ff15ca6..63858408 100644
--- a/lib/sockopt.c
+++ b/lib/sockopt.c
@@ -179,8 +179,19 @@ getsockopt_ipv6_ifindex (struct msghdr *msgh)
   
   return pktinfo->ipi6_ifindex;
 }
-#endif /* HAVE_IPV6 */
 
+int
+setsockopt_ipv6_tclass(int sock, int tclass)
+{
+  int ret;
+
+  ret = setsockopt (sock, IPPROTO_IPV6, IPV6_TCLASS, &tclass, sizeof (tclass));
+  if (ret < 0)
+    zlog_warn ("Can't set IPV6_TCLASS option for fd %d to %#x: %s",
+	       sock, tclass, safe_strerror(errno));
+  return ret;
+}
+#endif /* HAVE_IPV6 */
 
 /*
  * Process multicast socket options for IPv4 in an OS-dependent manner.