Set IPv4 TOS value for BGP

Bugfix 2847
Set TOS to internet control for BGP traffic

3 files changed, 29 insertions, 0 deletions

diff --git a/bgpd/bgp_network.c b/bgpd/bgp_network.c
index 4289ce20..e981e718 100644
--- a/bgpd/bgp_network.c
+++ b/bgpd/bgp_network.c
@@ -267,6 +267,11 @@ bgp_connect (struct peer *peer)
   sockopt_reuseaddr (peer->fd);
   sockopt_reuseport (peer->fd);
 
+#ifdef IPTOS_PREC_INTERNETCONTROL
+  if (sockunion_family (&peer->su) == AF_INET)
+    setsockopt_ipv4_tos (peer->fd, IPTOS_PREC_INTERNETCONTROL);
+#endif
+
 #ifdef HAVE_TCP_MD5SIG
   if (CHECK_FLAG (peer->flags, PEER_FLAG_PASSWORD))
     if (sockunion_family (&peer->su) == AF_INET)
@@ -362,6 +367,11 @@ bgp_socket (struct bgp *bgp, unsigned short port, char *address)
       sockopt_reuseaddr (sock);
       sockopt_reuseport (sock);
       
+#ifdef IPTOS_PREC_INTERNETCONTROL
+      if (ainfo->ai_family == AF_INET)
+	setsockopt_ipv4_tos (sock, IPTOS_PREC_INTERNETCONTROL);
+#endif
+
 #if defined(HAVE_TCP_MD5SIG) && defined(IPV6_V6ONLY)
 /*	We can not apply MD5SIG to an IPv6 socket.  If this is an AF_INET6
 	socket, we'll have to create another socket for IPv4*/
@@ -419,6 +429,7 @@ bgp_socket (struct bgp *bgp, unsigned short port, char *address)
 
       sockopt_reuseaddr (sock);
       sockopt_reuseport (sock);
+      setsockopt_ipv4_tos (sock, IPTOS_PREC_INTERNETCONTROL);
 
       memset (&sin, 0, sizeof (struct sockaddr_in));
 
@@ -486,6 +497,10 @@ bgp_socket (struct bgp *bgp, unsigned short port, char *address)
   sockopt_reuseaddr (sock);
   sockopt_reuseport (sock);
 
+#ifdef IPTOS_PREC_INTERNETCONTROL
+  setsockopt_ipv4_tos (sock, IPTOS_PREC_INTERNETCONTROL);
+#endif
+
   memset (&sin, 0, sizeof (struct sockaddr_in));
 
   sin.sin_family = AF_INET;
diff --git a/lib/sockopt.c b/lib/sockopt.c
index 985c3a38..e0027e88 100644
--- a/lib/sockopt.c
+++ b/lib/sockopt.c
@@ -342,6 +342,19 @@ setsockopt_ipv4_ifindex (int sock, int val)
 }
 
 int
+setsockopt_ipv4_tos(int sock, int tos)
+{
+  int ret;
+
+  ret = setsockopt (sock, IPPROTO_IP, IP_TOS, &tos, sizeof (tos));
+  if (ret < 0)
+    zlog_warn ("Can't set IP_TOS option for fd %d to %#x: %s",
+	       sock, tos, safe_strerror(errno));
+  return ret;
+}
+
+
+int
 setsockopt_ifindex (int af, int sock, int val)
 {
   int ret = -1;
diff --git a/lib/sockopt.h b/lib/sockopt.h
index 158f17ac..df0de61c 100644
--- a/lib/sockopt.h
+++ b/lib/sockopt.h
@@ -87,6 +87,7 @@ extern int setsockopt_multicast_ipv4(int sock, int optname,
 			             unsigned int ifindex
 					 /* optional: if non-zero, may be used
 					 	instead of if_addr */);
+extern int setsockopt_ipv4_tos(int sock, int tos);
 
 /* Ask for, and get, ifindex, by whatever method is supported. */
 extern int setsockopt_ifindex (int, int, int);