Merge pull request #16987 from opensourcerouting/bfd-echo-sock

bfdd: disable echo socket when not using it

2 files changed, 105 insertions, 48 deletions

diff --git a/bfdd/bfd.c b/bfdd/bfd.c
index eb9c300313..f32bc2598b 100644
--- a/bfdd/bfd.c
+++ b/bfdd/bfd.c
@@ -1172,6 +1172,9 @@ void bfd_set_echo(struct bfd_session *bs, bool echo)
 		if (bs->bdc == NULL)
 			ptm_bfd_echo_stop(bs);
 	}
+
+	if (bs->vrf && bs->vrf->info)
+		bfd_vrf_toggle_echo(bs->vrf->info);
 }
 
 void bfd_set_shutdown(struct bfd_session *bs, bool shutdown)
@@ -1800,6 +1803,69 @@ void bfd_profiles_remove(void)
 		bfd_profile_free(bp);
 }
 
+struct __bfd_session_echo {
+	/* VRF peers must match */
+	struct vrf *vrf;
+	/* Echo enabled or not */
+	bool enabled;
+};
+
+static int __bfd_session_has_echo(struct hash_bucket *hb, void *arg)
+{
+	const struct bfd_session *session = hb->data;
+	struct __bfd_session_echo *has_echo = arg;
+
+	if (session->vrf != has_echo->vrf)
+		return HASHWALK_CONTINUE;
+	if (!CHECK_FLAG(session->flags, BFD_SESS_FLAG_ECHO))
+		return HASHWALK_CONTINUE;
+
+	has_echo->enabled = true;
+	return HASHWALK_ABORT;
+}
+
+void bfd_vrf_toggle_echo(struct bfd_vrf_global *bfd_vrf)
+{
+	struct __bfd_session_echo has_echo = {
+		.enabled = false,
+		.vrf = bfd_vrf->vrf,
+	};
+
+	/* Check for peers using echo */
+	hash_walk(bfd_id_hash, __bfd_session_has_echo, &has_echo);
+
+	/*
+	 * No peers using echo, close all echo sockets.
+	 */
+	if (!has_echo.enabled) {
+		if (bfd_vrf->bg_echo != -1) {
+			event_cancel(&bfd_vrf->bg_ev[4]);
+			close(bfd_vrf->bg_echo);
+			bfd_vrf->bg_echo = -1;
+		}
+
+		if (bfd_vrf->bg_echov6 != -1) {
+			event_cancel(&bfd_vrf->bg_ev[5]);
+			close(bfd_vrf->bg_echov6);
+			bfd_vrf->bg_echov6 = -1;
+		}
+		return;
+	}
+
+	/*
+	 * At least one peer using echo, open echo sockets.
+	 */
+	if (bfd_vrf->bg_echo == -1)
+		bfd_vrf->bg_echo = bp_echo_socket(bfd_vrf->vrf);
+	if (bfd_vrf->bg_echov6 == -1)
+		bfd_vrf->bg_echov6 = bp_echov6_socket(bfd_vrf->vrf);
+
+	if (bfd_vrf->bg_ev[4] == NULL && bfd_vrf->bg_echo != -1)
+		event_add_read(master, bfd_recv_cb, bfd_vrf, bfd_vrf->bg_echo, &bfd_vrf->bg_ev[4]);
+	if (bfd_vrf->bg_ev[5] == NULL && bfd_vrf->bg_echov6 != -1)
+		event_add_read(master, bfd_recv_cb, bfd_vrf, bfd_vrf->bg_echov6, &bfd_vrf->bg_ev[5]);
+}
+
 /*
  * Profile related hash functions.
  */
@@ -1842,9 +1908,23 @@ static void bfd_profile_detach(struct bfd_profile *bp)
  */
 static int bfd_vrf_new(struct vrf *vrf)
 {
+	struct bfd_vrf_global *bvrf;
+
 	if (bglobal.debug_zebra)
 		zlog_debug("VRF Created: %s(%u)", vrf->name, vrf->vrf_id);
 
+	bvrf = XCALLOC(MTYPE_BFDD_VRF, sizeof(struct bfd_vrf_global));
+	bvrf->vrf = vrf;
+	vrf->info = bvrf;
+
+	/* Invalidate all sockets */
+	bvrf->bg_shop = -1;
+	bvrf->bg_mhop = -1;
+	bvrf->bg_shop6 = -1;
+	bvrf->bg_mhop6 = -1;
+	bvrf->bg_echo = -1;
+	bvrf->bg_echov6 = -1;
+
 	return 0;
 }
 
@@ -1853,70 +1933,53 @@ static int bfd_vrf_delete(struct vrf *vrf)
 	if (bglobal.debug_zebra)
 		zlog_debug("VRF Deletion: %s(%u)", vrf->name, vrf->vrf_id);
 
+	XFREE(MTYPE_BFDD_VRF, vrf->info);
+
 	return 0;
 }
 
 static int bfd_vrf_enable(struct vrf *vrf)
 {
-	struct bfd_vrf_global *bvrf;
-
-	/* a different name */
-	if (!vrf->info) {
-		bvrf = XCALLOC(MTYPE_BFDD_VRF, sizeof(struct bfd_vrf_global));
-		bvrf->vrf = vrf;
-		vrf->info = (void *)bvrf;
-
-		/* Disable sockets if using data plane. */
-		if (bglobal.bg_use_dplane) {
-			bvrf->bg_shop = -1;
-			bvrf->bg_mhop = -1;
-			bvrf->bg_shop6 = -1;
-			bvrf->bg_mhop6 = -1;
-			bvrf->bg_echo = -1;
-			bvrf->bg_echov6 = -1;
-		}
-	} else
-		bvrf = vrf->info;
+	struct bfd_vrf_global *bvrf = vrf->info;
 
 	if (bglobal.debug_zebra)
 		zlog_debug("VRF enable add %s id %u", vrf->name, vrf->vrf_id);
 
-	if (!bvrf->bg_shop)
+	/* Don't open sockets when using data plane */
+	if (bglobal.bg_use_dplane)
+		goto skip_sockets;
+
+	if (bvrf->bg_shop == -1)
 		bvrf->bg_shop = bp_udp_shop(vrf);
-	if (!bvrf->bg_mhop)
+	if (bvrf->bg_mhop == -1)
 		bvrf->bg_mhop = bp_udp_mhop(vrf);
-	if (!bvrf->bg_shop6)
+	if (bvrf->bg_shop6 == -1)
 		bvrf->bg_shop6 = bp_udp6_shop(vrf);
-	if (!bvrf->bg_mhop6)
+	if (bvrf->bg_mhop6 == -1)
 		bvrf->bg_mhop6 = bp_udp6_mhop(vrf);
-	if (!bvrf->bg_echo)
-		bvrf->bg_echo = bp_echo_socket(vrf);
-	if (!bvrf->bg_echov6)
-		bvrf->bg_echov6 = bp_echov6_socket(vrf);
 
-	if (!bvrf->bg_ev[0] && bvrf->bg_shop != -1)
+	if (bvrf->bg_ev[0] == NULL && bvrf->bg_shop != -1)
 		event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_shop,
 			       &bvrf->bg_ev[0]);
-	if (!bvrf->bg_ev[1] && bvrf->bg_mhop != -1)
+	if (bvrf->bg_ev[1] == NULL && bvrf->bg_mhop != -1)
 		event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_mhop,
 			       &bvrf->bg_ev[1]);
-	if (!bvrf->bg_ev[2] && bvrf->bg_shop6 != -1)
+	if (bvrf->bg_ev[2] == NULL && bvrf->bg_shop6 != -1)
 		event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_shop6,
 			       &bvrf->bg_ev[2]);
-	if (!bvrf->bg_ev[3] && bvrf->bg_mhop6 != -1)
+	if (bvrf->bg_ev[3] == NULL && bvrf->bg_mhop6 != -1)
 		event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_mhop6,
 			       &bvrf->bg_ev[3]);
-	if (!bvrf->bg_ev[4] && bvrf->bg_echo != -1)
-		event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_echo,
-			       &bvrf->bg_ev[4]);
-	if (!bvrf->bg_ev[5] && bvrf->bg_echov6 != -1)
-		event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_echov6,
-			       &bvrf->bg_ev[5]);
 
+	/* Toggle echo if VRF was disabled. */
+	bfd_vrf_toggle_echo(bvrf);
+
+skip_sockets:
 	if (vrf->vrf_id != VRF_DEFAULT) {
 		bfdd_zclient_register(vrf->vrf_id);
 		bfdd_sessions_enable_vrf(vrf);
 	}
+
 	return 0;
 }
 
@@ -1948,17 +2011,9 @@ static int bfd_vrf_disable(struct vrf *vrf)
 	socket_close(&bvrf->bg_echo);
 	socket_close(&bvrf->bg_shop);
 	socket_close(&bvrf->bg_mhop);
-	if (bvrf->bg_shop6 != -1)
-		socket_close(&bvrf->bg_shop6);
-	if (bvrf->bg_mhop6 != -1)
-		socket_close(&bvrf->bg_mhop6);
-	socket_close(&bvrf->bg_echo);
-	if (bvrf->bg_echov6 != -1)
-		socket_close(&bvrf->bg_echov6);
-
-	/* free context */
-	XFREE(MTYPE_BFDD_VRF, bvrf);
-	vrf->info = NULL;
+	socket_close(&bvrf->bg_shop6);
+	socket_close(&bvrf->bg_mhop6);
+	socket_close(&bvrf->bg_echov6);
 
 	return 0;
 }
diff --git a/bfdd/bfd.h b/bfdd/bfd.h
index 2f83b245eb..d4d14ffce6 100644
--- a/bfdd/bfd.h
+++ b/bfdd/bfd.h
@@ -610,6 +610,8 @@ void bfd_sessions_remove_manual(void);
 void bfd_profiles_remove(void);
 void bfd_rtt_init(struct bfd_session *bfd);
 
+extern void bfd_vrf_toggle_echo(struct bfd_vrf_global *bfd_vrf);
+
 /**
  * Set the BFD session echo state.
  *