ldp: decode PW Status TLV

print-ldp.c

@@ -145,6 +145,7 @@ static const struct tok ldp_msg_values[] = {
 #define	LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
 #define LDP_TLV_MTU                  0x0601 /* rfc 3988 */
 #define LDP_TLV_DUAL_STACK_CAP       0x0701 /* rfc 7552 */
+#define LDP_TLV_PW_STATUS            0x096a /* rfc 8077 */
 
 static const struct tok ldp_tlv_values[] = {
     { LDP_TLV_FEC,	             "FEC" },
@@ -170,6 +171,7 @@ static const struct tok ldp_tlv_values[] = {
     { LDP_TLV_LABEL_REQUEST_MSG_ID,  "Label Request Message ID" },
     { LDP_TLV_MTU,                   "MTU" },
     { LDP_TLV_DUAL_STACK_CAP,        "Dual-Stack Capability" },
+    { LDP_TLV_PW_STATUS,             "PW Status" },
     { 0, NULL}
 };
 
@@ -255,6 +257,19 @@ static const struct tok ldp_dual_stack_transport_pref_values[] = {
     { 0, NULL}
 };
 
+static const struct tok ldp_pw_status_flags[] = {
+    /* rfc 8077 */
+    { 0x01, "NF" }, /* Pseudowire Not Forwarding */
+    { 0x02, "AC-RF" }, /* Local Attachment Circuit (ingress) Receive Fault */
+    { 0x04, "AC-TF" }, /* Local Attachment Circuit (egress) Transmit Fault */
+    { 0x08, "PSN-RF" }, /* Local PSN-facing PW (ingress) Receive Fault */
+    { 0x10, "PSN-TF" }, /* Local PSN-facing PW (egress) Transmit Fault */
+    /* rfc 6870 */
+    { 0x20, "PF" }, /* PW Preferential Forwarding Status */
+    { 0x40, "RS" }, /* PW Request Switchover Status */
+    { 0, NULL}
+};
+
 static u_int ldp_pdu_print(netdissect_options *, const u_char *);
 
 /*
@@ -589,6 +604,13 @@ ldp_tlv_print(netdissect_options *ndo,
 			 transport_pref));
 	break;
 
+    case LDP_TLV_PW_STATUS:
+	ND_ICHECKMSG_U("tlv length", tlv_tlen, <, 4);
+	ND_PRINT("\n\t      PW Status: 0x%02x [%s]",
+	         GET_BE_U_4(tptr),
+	         bittok2str(ldp_pw_status_flags, "none", GET_BE_U_4(tptr)));
+	break;
+
     /*
      *  FIXME those are the defined TLVs that lack a decoder
      *  you are welcome to contribute code ;-)

tests/TESTLIST

@@ -121,6 +121,7 @@ lmp		lmp.pcap		lmp.out -T lmp
 mpls-ldp-hello	mpls-ldp-hello.pcap	mpls-ldp-hello.out -v
 ldp-common-session ldp-common-session.pcap ldp-common-session.out -v
 ldp_infloop	ldp-infinite-loop.pcap	ldp_infloop.out
+ldp-pw-status ldp-pw-status.pcap ldp-pw-status.out -v
 lspping-fec-ldp    lspping-fec-ldp.pcap lspping-fec-ldp.out
 lspping-fec-ldp-v  lspping-fec-ldp.pcap lspping-fec-ldp-v.out -v
 lspping-fec-ldp-vv lspping-fec-ldp.pcap lspping-fec-ldp-vv.out -vv

tests/ldp-pw-status.out

@@ -0,0 +1,10 @@
+    1  00:30:47.522169 IP (tos 0xc0, ttl 64, id 944, offset 0, flags [DF], proto TCP (6), length 108)
+    2.2.2.2.45781 > 1.1.1.1.646: Flags [P.], cksum 0xd2d9 (correct), seq 4026114102:4026114158, ack 1839823399, win 128, options [nop,nop,TS val 2533630089 ecr 3448755034], length 56
+	LDP, Label-Space-ID: 2.2.2.2:0, pdu-length: 52
+	  Notification Message (0x0001), length: 42, Message ID: 0x0000002d, Flags: [ignore if unknown]
+	    Status TLV (0x0300), length: 10, Flags: [ignore and don't forward if unknown]
+	      Status Code: Unknown, Flags: [Advisory Notification and don't forward]
+	    PW Status TLV (0x096a), length: 4, Flags: [continue processing and don't forward if unknown]
+	      PW Status: 0x06 [AC-RF, AC-TF]
+	    FEC TLV (0x0100), length: 12, Flags: [ignore and don't forward if unknown]
+	      Martini VC FEC (0x80): Ethernet, no control word, group-ID 0, VC-ID 1, VC-info-length: 4