Merge pull request #11371 from rampxxxx/feat_bfd_ipv4_echo_fwd_path

bfdd: add IPv4 BFD Echo support that loops pkts in forwarding plane

bfdd/bfd.c

@@ -454,7 +454,17 @@ void ptm_bfd_start_xmt_timer(struct bfd_session *bfd, bool is_echo)
 static void ptm_bfd_echo_xmt_TO(struct bfd_session *bfd)
 {
 	/* Send the scheduled echo  packet */
-	ptm_bfd_echo_snd(bfd);
+	/* if ipv4 use the new echo implementation that causes
+	 * the packet to be looped in forwarding plane of peer
+	 */
+	if (CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_IPV6) == 0)
+#ifdef BFD_LINUX
+		ptm_bfd_echo_fp_snd(bfd);
+#else
+		ptm_bfd_echo_snd(bfd);
+#endif
+	else
+		ptm_bfd_echo_snd(bfd);
 
 	/* Restart the timer for next time */
 	ptm_bfd_start_xmt_timer(bfd, true);
@@ -558,6 +568,12 @@ void ptm_bfd_sess_dn(struct bfd_session *bfd, uint8_t diag)
 				   state_list[bfd->ses_state].str,
 				   get_diag_str(bfd->local_diag));
 	}
+
+	/* clear peer's mac address */
+	UNSET_FLAG(bfd->flags, BFD_SESS_FLAG_MAC_SET);
+	memset(bfd->peer_hw_addr, 0, sizeof(bfd->peer_hw_addr));
+	/* reset local address ,it might has been be changed after bfd is up*/
+	memset(&bfd->local_address, 0, sizeof(bfd->local_address));
 }
 
 static struct bfd_session *bfd_find_disc(struct sockaddr_any *sa,

bfdd/bfd.h

@@ -168,9 +168,10 @@ enum bfd_session_flags {
 						 * expires
 						 */
 	BFD_SESS_FLAG_SHUTDOWN = 1 << 7,	/* disable BGP peer function */
-	BFD_SESS_FLAG_CONFIG = 1 << 8,	/* Session configured with bfd NB API */
-	BFD_SESS_FLAG_CBIT = 1 << 9,	/* CBIT is set */
+	BFD_SESS_FLAG_CONFIG = 1 << 8, /* Session configured with bfd NB API */
+	BFD_SESS_FLAG_CBIT = 1 << 9,   /* CBIT is set */
 	BFD_SESS_FLAG_PASSIVE = 1 << 10, /* Passive mode */
+	BFD_SESS_FLAG_MAC_SET = 1 << 11, /* MAC of peer known */
 };
 
 /*
@@ -290,6 +291,8 @@ struct bfd_session {
 	struct peer_label *pl;
 
 	struct bfd_dplane_ctx *bdc;
+	struct sockaddr_any local_address;
+	uint8_t peer_hw_addr[ETH_ALEN];
 	struct interface *ifp;
 	struct vrf *vrf;
 
@@ -554,6 +557,7 @@ int bp_echov6_socket(const struct vrf *vrf);
 
 void ptm_bfd_snd(struct bfd_session *bfd, int fbit);
 void ptm_bfd_echo_snd(struct bfd_session *bfd);
+void ptm_bfd_echo_fp_snd(struct bfd_session *bfd);
 
 void bfd_recv_cb(struct thread *t);