BFD: add SBFD support (RFC7880 and RFC7881)

Add support for SBFD on UDP port 7784.  SBFD is different
in that packets from the reflector will be sent with *source*
port 7784; in all other BFD mechanisms, it is only the
destination port that matters.  For SBFD print-udp.c has to
check both source and destination port.

1 files changed, 3 insertions, 0 deletions

diff --git a/udp.h b/udp.h
index 70d3315a..c6eb873e 100644
--- a/udp.h
+++ b/udp.h
@@ -218,6 +218,9 @@ struct udphdr {
 #ifndef BFD_LAG_PORT
 #define BFD_LAG_PORT			6784	/* RFC 7310 */
 #endif
+#ifndef SBFD_PORT
+#define SBFD_PORT			7784	/* SBFD RFC 7880 */
+#endif
 #ifndef RX_PORT_LOW
 #define RX_PORT_LOW			7000	/*XXX*/
 #endif