Merge pull request #1821 from vivek-cumulus/pmsi-parse-display

bgpd: Parse PMSI Tunnel Attribute and display

bgpd/bgp_attr.c

@@ -2107,6 +2107,51 @@ bgp_attr_prefix_sid(struct bgp_attr_parser_args *args,
 	return BGP_ATTR_PARSE_PROCEED;
 }
 
+/* PMSI tunnel attribute (RFC 6514)
+ * Basic validation checks done here.
+ */
+static bgp_attr_parse_ret_t
+bgp_attr_pmsi_tunnel(struct bgp_attr_parser_args *args)
+{
+	struct peer *const peer = args->peer;
+	struct attr *const attr = args->attr;
+	const bgp_size_t length = args->length;
+	u_int8_t tnl_type;
+
+	/* Verify that the receiver is expecting "ingress replication" as we
+	 * can only support that.
+	 */
+	if (length < 2) {
+		zlog_err("Bad PMSI tunnel attribute length %d", length);
+		return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
+					  args->total);
+	}
+	stream_getc(peer->curr); /* Flags */
+	tnl_type = stream_getc(peer->curr);
+	if (tnl_type > PMSI_TNLTYPE_MAX) {
+		zlog_err("Invalid PMSI tunnel attribute type %d", tnl_type);
+		return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
+					  args->total);
+	}
+	if (tnl_type == PMSI_TNLTYPE_INGR_REPL) {
+		if (length != 9) {
+			zlog_err("Bad PMSI tunnel attribute length %d for IR",
+				 length);
+			return bgp_attr_malformed(
+				args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
+				args->total);
+		}
+	}
+
+	attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_PMSI_TUNNEL);
+	attr->pmsi_tnl_type = tnl_type;
+
+	/* Forward read pointer of input stream. */
+	stream_forward_getp(peer->curr, length - 2);
+
+	return BGP_ATTR_PARSE_PROCEED;
+}
+
 /* BGP unknown attribute treatment. */
 static bgp_attr_parse_ret_t bgp_attr_unknown(struct bgp_attr_parser_args *args)
 {
@@ -2440,6 +2485,9 @@ bgp_attr_parse_ret_t bgp_attr_parse(struct peer *peer, struct attr *attr,
 		case BGP_ATTR_PREFIX_SID:
 			ret = bgp_attr_prefix_sid(&attr_args, mp_update);
 			break;
+		case BGP_ATTR_PMSI_TUNNEL:
+			ret = bgp_attr_pmsi_tunnel(&attr_args);
+			break;
 		default:
 			ret = bgp_attr_unknown(&attr_args);
 			break;
@@ -3263,7 +3311,7 @@ bgp_size_t bgp_packet_attribute(struct bgp *bgp, struct peer *peer,
 		stream_putc(s, BGP_ATTR_PMSI_TUNNEL);
 		stream_putc(s, 9); // Length
 		stream_putc(s, 0); // Flags
-		stream_putc(s, 6); // Tunnel type: Ingress Replication (6)
+		stream_putc(s, PMSI_TNLTYPE_INGR_REPL); // IR (6)
 		stream_put(s, &(attr->label),
 			   BGP_LABEL_BYTES); // MPLS Label / VXLAN VNI
 		stream_put_ipv4(s, attr->nexthop.s_addr);

bgpd/bgp_attr.h

@@ -66,6 +66,8 @@
 #define BGP_PREFIX_SID_IPV6_LENGTH            19
 #define BGP_PREFIX_SID_ORIGINATOR_SRGB_LENGTH  6
 
+/* PMSI tunnel types (RFC 6514) */
+
 struct bgp_attr_encap_subtlv {
 	struct bgp_attr_encap_subtlv *next; /* for chaining */
 	/* Reference count of this attribute. */
@@ -96,6 +98,18 @@ struct overlay_index {
 	union gw_addr gw_ip;
 };
 
+enum pta_type {
+	PMSI_TNLTYPE_NO_INFO = 0,
+	PMSI_TNLTYPE_RSVP_TE_P2MP,
+	PMSI_TNLTYPE_MLDP_P2MP,
+	PMSI_TNLTYPE_PIM_SSM,
+	PMSI_TNLTYPE_PIM_SM,
+	PMSI_TNLTYPE_PIM_BIDIR,
+	PMSI_TNLTYPE_INGR_REPL,
+	PMSI_TNLTYPE_MLDP_MP2MP,
+	PMSI_TNLTYPE_MAX = PMSI_TNLTYPE_MLDP_MP2MP
+};
+
 /* BGP core attribute structure. */
 struct attr {
 	/* AS Path structure */
@@ -119,6 +133,9 @@ struct attr {
 	/* Path origin attribute */
 	u_char origin;
 
+	/* PMSI tunnel type (RFC 6514). */
+	enum pta_type pmsi_tnl_type;
+
 	/* has the route-map changed any attribute?
 	   Used on the peer outbound side. */
 	u_int32_t rmap_change_flags;

bgpd/bgp_debug.c

@@ -160,7 +160,6 @@ static const struct message bgp_notify_capability_msg[] = {
 const char *bgp_origin_str[] = {"i", "e", "?"};
 const char *bgp_origin_long_str[] = {"IGP", "EGP", "incomplete"};
 
-
 /* Given a string return a pointer the corresponding peer structure */
 static struct peer *bgp_find_peer(struct vty *vty, const char *peer_str)
 {
@@ -415,6 +414,10 @@ int bgp_dump_attr(struct attr *attr, char *buf, size_t size)
 				 inet_ntoa(attr->cluster->list[i]));
 	}
 
+	if (CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_PMSI_TUNNEL)))
+		snprintf(buf + strlen(buf), size - strlen(buf),
+			 ", pmsi tnltype %u", attr->pmsi_tnl_type);
+
 	if (CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_AS_PATH)))
 		snprintf(buf + strlen(buf), size - strlen(buf), ", path %s",
 			 aspath_print(attr->aspath));

bgpd/bgp_debug.h

@@ -136,6 +136,7 @@ struct bgp_debug_filter {
 #define CONF_BGP_DEBUG(a, b)    (conf_bgp_debug_ ## a & BGP_DEBUG_ ## b)
 
 extern const char *bgp_type_str[];
+extern const char *pmsi_tnltype_str[];
 
 extern int bgp_dump_attr(struct attr *, char *, size_t);
 extern int bgp_debug_peer_updout_enabled(char *host);

bgpd/bgp_evpn.c

@@ -2935,6 +2935,19 @@ static int process_type3_route(struct peer *peer, afi_t afi, safi_t safi,
 		return -1;
 	}
 
+	/* If PMSI is present, log if it is anything other than IR.
+	 * Note: We just simply ignore the values as it is not clear if
+	 * doing anything else is better.
+	 */
+	if (attr &&
+	    (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_PMSI_TUNNEL))) {
+		if (attr->pmsi_tnl_type != PMSI_TNLTYPE_INGR_REPL) {
+			zlog_warn("%u:%s - Rx EVPN Type-3 NLRI with unsupported PTA %d",
+				  peer->bgp->vrf_id, peer->host,
+				  attr->pmsi_tnl_type);
+		}
+	}
+
 	/* Make prefix_rd */
 	prd.family = AF_UNSPEC;
 	prd.prefixlen = 64;

bgpd/bgp_route.c

@@ -82,6 +82,21 @@
 extern const char *bgp_origin_str[];
 extern const char *bgp_origin_long_str[];
 
+/* PMSI strings. */
+#define PMSI_TNLTYPE_STR_NO_INFO "No info"
+#define PMSI_TNLTYPE_STR_DEFAULT PMSI_TNLTYPE_STR_NO_INFO
+static const struct message bgp_pmsi_tnltype_str[] = {
+	{PMSI_TNLTYPE_NO_INFO, PMSI_TNLTYPE_STR_NO_INFO},
+	{PMSI_TNLTYPE_RSVP_TE_P2MP, "RSVP-TE P2MP"},
+	{PMSI_TNLTYPE_MLDP_P2MP, "mLDP P2MP"},
+	{PMSI_TNLTYPE_PIM_SSM, "PIM-SSM"},
+	{PMSI_TNLTYPE_PIM_SM, "PIM-SM"},
+	{PMSI_TNLTYPE_PIM_BIDIR, "PIM-BIDIR"},
+	{PMSI_TNLTYPE_INGR_REPL, "Ingress Replication"},
+	{PMSI_TNLTYPE_MLDP_MP2MP, "mLDP MP2MP"},
+	{0}
+};
+
 struct bgp_node *bgp_afi_node_get(struct bgp_table *table, afi_t afi,
 				  safi_t safi, struct prefix *p,
 				  struct prefix_rd *prd)
@@ -7035,6 +7050,7 @@ void route_vty_out_detail(struct vty *vty, struct bgp *bgp, struct prefix *p,
 	json_object *json_ext_community = NULL;
 	json_object *json_lcommunity = NULL;
 	json_object *json_last_update = NULL;
+	json_object *json_pmsi = NULL;
 	json_object *json_nexthop_global = NULL;
 	json_object *json_nexthop_ll = NULL;
 	json_object *json_nexthops = NULL;
@@ -7787,6 +7803,24 @@ void route_vty_out_detail(struct vty *vty, struct bgp *bgp, struct prefix *p,
 					       json_last_update);
 		} else
 			vty_out(vty, "      Last update: %s", ctime(&tbuf));
+
+		/* Line 10 display PMSI tunnel attribute, if present */
+		if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_PMSI_TUNNEL)) {
+			const char *str = lookup_msg(bgp_pmsi_tnltype_str,
+						     attr->pmsi_tnl_type,
+						     PMSI_TNLTYPE_STR_DEFAULT);
+
+			if (json_paths) {
+				json_pmsi = json_object_new_object();
+				json_object_string_add(json_pmsi,
+						       "tunnelType", str);
+				json_object_object_add(json_path, "pmsi",
+						       json_pmsi);
+			} else
+				vty_out(vty, "      PMSI Tunnel Type: %s\n",
+					str);
+		}
+
 	}
 
 	/* We've constructed the json object for this path, add it to the json