xref: /freebsd/contrib/tcpdump/print-cfm.c (revision 257e70f1d5ee61037c8c59b116538d3b6b1427a2)
1 /*
2  * Copyright (c) 1998-2006 The TCPDUMP project
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that: (1) source code
6  * distributions retain the above copyright notice and this paragraph
7  * in its entirety, and (2) distributions including binary code include
8  * the above copyright notice and this paragraph in its entirety in
9  * the documentation or other materials provided with the distribution.
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
11  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
12  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
13  * FOR A PARTICULAR PURPOSE.
14  *
15  * Original code by Hannes Gredler (hannes@gredler.at)
16  */
17 
18 /* \summary: IEEE 802.1ag Connectivity Fault Management (CFM) protocols printer */
19 
20 #ifdef HAVE_CONFIG_H
21 #include <config.h>
22 #endif
23 
24 #include "netdissect-stdinc.h"
25 
26 #include "netdissect.h"
27 #include "extract.h"
28 #include "addrtoname.h"
29 #include "oui.h"
30 #include "af.h"
31 
32 
33 struct cfm_common_header_t {
34     nd_uint8_t mdlevel_version;
35     nd_uint8_t opcode;
36     nd_uint8_t flags;
37     nd_uint8_t first_tlv_offset;
38 };
39 
40 #define	CFM_VERSION 0
41 #define CFM_EXTRACT_VERSION(x) ((x)&0x1f)
42 #define CFM_EXTRACT_MD_LEVEL(x) (((x)&0xe0)>>5)
43 
44 #define	CFM_OPCODE_CCM 1
45 #define	CFM_OPCODE_LBR 2
46 #define	CFM_OPCODE_LBM 3
47 #define	CFM_OPCODE_LTR 4
48 #define	CFM_OPCODE_LTM 5
49 
50 static const struct tok cfm_opcode_values[] = {
51     { CFM_OPCODE_CCM, "Continuity Check Message"},
52     { CFM_OPCODE_LBR, "Loopback Reply"},
53     { CFM_OPCODE_LBM, "Loopback Message"},
54     { CFM_OPCODE_LTR, "Linktrace Reply"},
55     { CFM_OPCODE_LTM, "Linktrace Message"},
56     { 0, NULL}
57 };
58 
59 /*
60  * Message Formats.
61  */
62 struct cfm_ccm_t {
63     nd_uint32_t sequence;
64     nd_uint16_t ma_epi;
65     nd_byte     names[48];
66     nd_byte     itu_t_y_1731[16];
67 };
68 
69 /*
70  * Timer Bases for the CCM Interval field.
71  * Expressed in units of seconds.
72  */
73 static const float ccm_interval_base[8] = {0.0f, 0.003333f, 0.01f, 0.1f, 1.0f, 10.0f, 60.0f, 600.0f};
74 #define CCM_INTERVAL_MIN_MULTIPLIER 3.25
75 #define CCM_INTERVAL_MAX_MULTIPLIER 3.5
76 
77 #define CFM_CCM_RDI_FLAG 0x80
78 #define CFM_EXTRACT_CCM_INTERVAL(x) ((x)&0x07)
79 
80 #define CFM_CCM_MD_FORMAT_8021 0
81 #define CFM_CCM_MD_FORMAT_NONE 1
82 #define CFM_CCM_MD_FORMAT_DNS  2
83 #define CFM_CCM_MD_FORMAT_MAC  3
84 #define CFM_CCM_MD_FORMAT_CHAR 4
85 
86 static const struct tok cfm_md_nameformat_values[] = {
87     { CFM_CCM_MD_FORMAT_8021, "IEEE 802.1"},
88     { CFM_CCM_MD_FORMAT_NONE, "No MD Name present"},
89     { CFM_CCM_MD_FORMAT_DNS, "DNS string"},
90     { CFM_CCM_MD_FORMAT_MAC, "MAC + 16Bit Integer"},
91     { CFM_CCM_MD_FORMAT_CHAR, "Character string"},
92     { 0, NULL}
93 };
94 
95 #define CFM_CCM_MA_FORMAT_8021 0
96 #define CFM_CCM_MA_FORMAT_VID  1
97 #define CFM_CCM_MA_FORMAT_CHAR 2
98 #define CFM_CCM_MA_FORMAT_INT  3
99 #define CFM_CCM_MA_FORMAT_VPN  4
100 
101 static const struct tok cfm_ma_nameformat_values[] = {
102     { CFM_CCM_MA_FORMAT_8021, "IEEE 802.1"},
103     { CFM_CCM_MA_FORMAT_VID, "Primary VID"},
104     { CFM_CCM_MA_FORMAT_CHAR, "Character string"},
105     { CFM_CCM_MA_FORMAT_INT, "16Bit Integer"},
106     { CFM_CCM_MA_FORMAT_VPN, "RFC2685 VPN-ID"},
107     { 0, NULL}
108 };
109 
110 struct cfm_lbm_t {
111     nd_uint32_t transaction_id;
112 };
113 
114 struct cfm_ltm_t {
115     nd_uint32_t transaction_id;
116     nd_uint8_t  ttl;
117     nd_mac_addr original_mac;
118     nd_mac_addr target_mac;
119 };
120 
121 static const struct tok cfm_ltm_flag_values[] = {
122     { 0x80, "Use Forwarding-DB only"},
123     { 0, NULL}
124 };
125 
126 struct cfm_ltr_t {
127     nd_uint32_t transaction_id;
128     nd_uint8_t  ttl;
129     nd_uint8_t  replay_action;
130 };
131 
132 static const struct tok cfm_ltr_flag_values[] = {
133     { 0x80, "UseFDB Only"},
134     { 0x40, "FwdYes"},
135     { 0x20, "Terminal MEP"},
136     { 0, NULL}
137 };
138 
139 static const struct tok cfm_ltr_replay_action_values[] = {
140     { 1, "Exact Match"},
141     { 2, "Filtering DB"},
142     { 3, "MIP CCM DB"},
143     { 0, NULL}
144 };
145 
146 
147 #define CFM_TLV_END 0
148 #define CFM_TLV_SENDER_ID 1
149 #define CFM_TLV_PORT_STATUS 2
150 #define CFM_TLV_INTERFACE_STATUS 3
151 #define CFM_TLV_DATA 4
152 #define CFM_TLV_REPLY_INGRESS 5
153 #define CFM_TLV_REPLY_EGRESS 6
154 #define CFM_TLV_PRIVATE 31
155 
156 static const struct tok cfm_tlv_values[] = {
157     { CFM_TLV_END, "End"},
158     { CFM_TLV_SENDER_ID, "Sender ID"},
159     { CFM_TLV_PORT_STATUS, "Port status"},
160     { CFM_TLV_INTERFACE_STATUS, "Interface status"},
161     { CFM_TLV_DATA, "Data"},
162     { CFM_TLV_REPLY_INGRESS, "Reply Ingress"},
163     { CFM_TLV_REPLY_EGRESS, "Reply Egress"},
164     { CFM_TLV_PRIVATE, "Organization Specific"},
165     { 0, NULL}
166 };
167 
168 /*
169  * TLVs
170  */
171 
172 struct cfm_tlv_header_t {
173     nd_uint8_t  type;
174     nd_uint16_t length;
175 };
176 
177 /* FIXME define TLV formats */
178 
179 static const struct tok cfm_tlv_port_status_values[] = {
180     { 1, "Blocked"},
181     { 2, "Up"},
182     { 0, NULL}
183 };
184 
185 static const struct tok cfm_tlv_interface_status_values[] = {
186     { 1, "Up"},
187     { 2, "Down"},
188     { 3, "Testing"},
189     { 5, "Dormant"},
190     { 6, "not present"},
191     { 7, "lower Layer down"},
192     { 0, NULL}
193 };
194 
195 #define CFM_CHASSIS_ID_CHASSIS_COMPONENT 1
196 #define CFM_CHASSIS_ID_INTERFACE_ALIAS 2
197 #define CFM_CHASSIS_ID_PORT_COMPONENT 3
198 #define CFM_CHASSIS_ID_MAC_ADDRESS 4
199 #define CFM_CHASSIS_ID_NETWORK_ADDRESS 5
200 #define CFM_CHASSIS_ID_INTERFACE_NAME 6
201 #define CFM_CHASSIS_ID_LOCAL 7
202 
203 static const struct tok cfm_tlv_senderid_chassisid_values[] = {
204     { 0, "Reserved"},
205     { CFM_CHASSIS_ID_CHASSIS_COMPONENT, "Chassis component"},
206     { CFM_CHASSIS_ID_INTERFACE_ALIAS, "Interface alias"},
207     { CFM_CHASSIS_ID_PORT_COMPONENT, "Port component"},
208     { CFM_CHASSIS_ID_MAC_ADDRESS, "MAC address"},
209     { CFM_CHASSIS_ID_NETWORK_ADDRESS, "Network address"},
210     { CFM_CHASSIS_ID_INTERFACE_NAME, "Interface name"},
211     { CFM_CHASSIS_ID_LOCAL, "Locally assigned"},
212     { 0, NULL}
213 };
214 
215 
216 static int
217 cfm_network_addr_print(netdissect_options *ndo,
218                        const u_char *tptr, const u_int length)
219 {
220     u_int network_addr_type;
221     u_int hexdump =  FALSE;
222 
223     /*
224      * Although AFIs are typically 2 octets wide,
225      * 802.1ab specifies that this field width
226      * is only one octet.
227      */
228     if (length < 1) {
229         ND_PRINT("\n\t  Network Address Type (invalid, no data");
230         return hexdump;
231     }
232     /* The calling function must make any due ND_TCHECK calls. */
233     network_addr_type = GET_U_1(tptr);
234     ND_PRINT("\n\t  Network Address Type %s (%u)",
235            tok2str(af_values, "Unknown", network_addr_type),
236            network_addr_type);
237 
238     /*
239      * Resolve the passed in Address.
240      */
241     switch(network_addr_type) {
242     case AFNUM_INET:
243         if (length != 1 + 4) {
244             ND_PRINT("(invalid IPv4 address length %u)", length - 1);
245             hexdump = TRUE;
246             break;
247         }
248         ND_PRINT(", %s", GET_IPADDR_STRING(tptr + 1));
249         break;
250 
251     case AFNUM_INET6:
252         if (length != 1 + 16) {
253             ND_PRINT("(invalid IPv6 address length %u)", length - 1);
254             hexdump = TRUE;
255             break;
256         }
257         ND_PRINT(", %s", GET_IP6ADDR_STRING(tptr + 1));
258         break;
259 
260     default:
261         hexdump = TRUE;
262         break;
263     }
264 
265     return hexdump;
266 }
267 
268 void
269 cfm_print(netdissect_options *ndo,
270           const u_char *pptr, u_int length)
271 {
272     const struct cfm_common_header_t *cfm_common_header;
273     uint8_t mdlevel_version, opcode, flags, first_tlv_offset;
274     const struct cfm_tlv_header_t *cfm_tlv_header;
275     const uint8_t *tptr, *tlv_ptr;
276     const uint8_t *namesp;
277     u_int names_data_remaining;
278     uint8_t md_nameformat, md_namelength;
279     const uint8_t *md_name;
280     uint8_t ma_nameformat, ma_namelength;
281     const uint8_t *ma_name;
282     u_int hexdump, tlen, cfm_tlv_len, cfm_tlv_type, ccm_interval;
283 
284 
285     union {
286         const struct cfm_ccm_t *cfm_ccm;
287         const struct cfm_lbm_t *cfm_lbm;
288         const struct cfm_ltm_t *cfm_ltm;
289         const struct cfm_ltr_t *cfm_ltr;
290     } msg_ptr;
291 
292     ndo->ndo_protocol = "cfm";
293     tptr=pptr;
294     cfm_common_header = (const struct cfm_common_header_t *)pptr;
295     if (length < sizeof(*cfm_common_header))
296         goto tooshort;
297     ND_TCHECK_SIZE(cfm_common_header);
298 
299     /*
300      * Sanity checking of the header.
301      */
302     mdlevel_version = GET_U_1(cfm_common_header->mdlevel_version);
303     if (CFM_EXTRACT_VERSION(mdlevel_version) != CFM_VERSION) {
304 	ND_PRINT("CFMv%u not supported, length %u",
305                CFM_EXTRACT_VERSION(mdlevel_version), length);
306 	return;
307     }
308 
309     opcode = GET_U_1(cfm_common_header->opcode);
310     ND_PRINT("CFMv%u %s, MD Level %u, length %u",
311            CFM_EXTRACT_VERSION(mdlevel_version),
312            tok2str(cfm_opcode_values, "unknown (%u)", opcode),
313            CFM_EXTRACT_MD_LEVEL(mdlevel_version),
314            length);
315 
316     /*
317      * In non-verbose mode just print the opcode and md-level.
318      */
319     if (ndo->ndo_vflag < 1) {
320         return;
321     }
322 
323     flags = GET_U_1(cfm_common_header->flags);
324     first_tlv_offset = GET_U_1(cfm_common_header->first_tlv_offset);
325     ND_PRINT("\n\tFirst TLV offset %u", first_tlv_offset);
326 
327     tptr += sizeof(struct cfm_common_header_t);
328     tlen = length - sizeof(struct cfm_common_header_t);
329 
330     /*
331      * Sanity check the first TLV offset.
332      */
333     if (first_tlv_offset > tlen) {
334         ND_PRINT(" (too large, must be <= %u)", tlen);
335         return;
336     }
337 
338     switch (opcode) {
339     case CFM_OPCODE_CCM:
340         msg_ptr.cfm_ccm = (const struct cfm_ccm_t *)tptr;
341         if (first_tlv_offset < sizeof(*msg_ptr.cfm_ccm)) {
342             ND_PRINT(" (too small 1, must be >= %zu)",
343                      sizeof(*msg_ptr.cfm_ccm));
344             return;
345         }
346         if (tlen < sizeof(*msg_ptr.cfm_ccm))
347             goto tooshort;
348         ND_TCHECK_SIZE(msg_ptr.cfm_ccm);
349 
350         ccm_interval = CFM_EXTRACT_CCM_INTERVAL(flags);
351         ND_PRINT(", Flags [CCM Interval %u%s]",
352                ccm_interval,
353                flags & CFM_CCM_RDI_FLAG ?
354                ", RDI" : "");
355 
356         /*
357          * Resolve the CCM interval field.
358          */
359         if (ccm_interval) {
360             ND_PRINT("\n\t  CCM Interval %.3fs"
361                    ", min CCM Lifetime %.3fs, max CCM Lifetime %.3fs",
362                    ccm_interval_base[ccm_interval],
363                    ccm_interval_base[ccm_interval] * CCM_INTERVAL_MIN_MULTIPLIER,
364                    ccm_interval_base[ccm_interval] * CCM_INTERVAL_MAX_MULTIPLIER);
365         }
366 
367         ND_PRINT("\n\t  Sequence Number 0x%08x, MA-End-Point-ID 0x%04x",
368                GET_BE_U_4(msg_ptr.cfm_ccm->sequence),
369                GET_BE_U_2(msg_ptr.cfm_ccm->ma_epi));
370 
371         namesp = msg_ptr.cfm_ccm->names;
372         names_data_remaining = sizeof(msg_ptr.cfm_ccm->names);
373 
374         /*
375          * Resolve the MD fields.
376          */
377         md_nameformat = GET_U_1(namesp);
378         namesp++;
379         names_data_remaining--;  /* We know this is != 0 */
380         if (md_nameformat != CFM_CCM_MD_FORMAT_NONE) {
381             md_namelength = GET_U_1(namesp);
382             namesp++;
383             names_data_remaining--; /* We know this is !=0 */
384             ND_PRINT("\n\t  MD Name Format %s (%u), MD Name length %u",
385                    tok2str(cfm_md_nameformat_values, "Unknown",
386                            md_nameformat),
387                    md_nameformat,
388                    md_namelength);
389 
390             /*
391              * -3 for the MA short name format and length and one byte
392              * of MA short name.
393              */
394             if (md_namelength > names_data_remaining - 3) {
395                 ND_PRINT(" (too large, must be <= %u)", names_data_remaining - 2);
396                 return;
397             }
398 
399             md_name = namesp;
400             ND_PRINT("\n\t  MD Name: ");
401             switch (md_nameformat) {
402             case CFM_CCM_MD_FORMAT_DNS:
403             case CFM_CCM_MD_FORMAT_CHAR:
404                 nd_printjnp(ndo, md_name, md_namelength);
405                 break;
406 
407             case CFM_CCM_MD_FORMAT_MAC:
408                 if (md_namelength == MAC_ADDR_LEN) {
409                     ND_PRINT("\n\t  MAC %s", GET_ETHERADDR_STRING(md_name));
410                 } else {
411                     ND_PRINT("\n\t  MAC (length invalid)");
412                 }
413                 break;
414 
415                 /* FIXME add printers for those MD formats - hexdump for now */
416             case CFM_CCM_MA_FORMAT_8021:
417             default:
418                 print_unknown_data(ndo, md_name, "\n\t    ",
419                                    md_namelength);
420             }
421             namesp += md_namelength;
422             names_data_remaining -= md_namelength;
423         } else {
424             ND_PRINT("\n\t  MD Name Format %s (%u)",
425                    tok2str(cfm_md_nameformat_values, "Unknown",
426                            md_nameformat),
427                    md_nameformat);
428         }
429 
430 
431         /*
432          * Resolve the MA fields.
433          */
434         ma_nameformat = GET_U_1(namesp);
435         namesp++;
436         names_data_remaining--; /* We know this is != 0 */
437         ma_namelength = GET_U_1(namesp);
438         namesp++;
439         names_data_remaining--; /* We know this is != 0 */
440         ND_PRINT("\n\t  MA Name-Format %s (%u), MA name length %u",
441                tok2str(cfm_ma_nameformat_values, "Unknown",
442                        ma_nameformat),
443                ma_nameformat,
444                ma_namelength);
445 
446         if (ma_namelength > names_data_remaining) {
447             ND_PRINT(" (too large, must be <= %u)", names_data_remaining);
448             return;
449         }
450 
451         ma_name = namesp;
452         ND_PRINT("\n\t  MA Name: ");
453         switch (ma_nameformat) {
454         case CFM_CCM_MA_FORMAT_CHAR:
455             nd_printjnp(ndo, ma_name, ma_namelength);
456             break;
457 
458             /* FIXME add printers for those MA formats - hexdump for now */
459         case CFM_CCM_MA_FORMAT_8021:
460         case CFM_CCM_MA_FORMAT_VID:
461         case CFM_CCM_MA_FORMAT_INT:
462         case CFM_CCM_MA_FORMAT_VPN:
463         default:
464             print_unknown_data(ndo, ma_name, "\n\t    ", ma_namelength);
465         }
466         break;
467 
468     case CFM_OPCODE_LTM:
469         msg_ptr.cfm_ltm = (const struct cfm_ltm_t *)tptr;
470         if (first_tlv_offset < sizeof(*msg_ptr.cfm_ltm)) {
471             ND_PRINT(" (too small 4, must be >= %zu)",
472                      sizeof(*msg_ptr.cfm_ltm));
473             return;
474         }
475         if (tlen < sizeof(*msg_ptr.cfm_ltm))
476             goto tooshort;
477         ND_TCHECK_SIZE(msg_ptr.cfm_ltm);
478 
479         ND_PRINT(", Flags [%s]",
480                bittok2str(cfm_ltm_flag_values, "none", flags));
481 
482         ND_PRINT("\n\t  Transaction-ID 0x%08x, ttl %u",
483                GET_BE_U_4(msg_ptr.cfm_ltm->transaction_id),
484                GET_U_1(msg_ptr.cfm_ltm->ttl));
485 
486         ND_PRINT("\n\t  Original-MAC %s, Target-MAC %s",
487                GET_ETHERADDR_STRING(msg_ptr.cfm_ltm->original_mac),
488                GET_ETHERADDR_STRING(msg_ptr.cfm_ltm->target_mac));
489         break;
490 
491     case CFM_OPCODE_LTR:
492         msg_ptr.cfm_ltr = (const struct cfm_ltr_t *)tptr;
493         if (first_tlv_offset < sizeof(*msg_ptr.cfm_ltr)) {
494             ND_PRINT(" (too small 5, must be >= %zu)",
495                      sizeof(*msg_ptr.cfm_ltr));
496             return;
497         }
498         if (tlen < sizeof(*msg_ptr.cfm_ltr))
499             goto tooshort;
500         ND_TCHECK_SIZE(msg_ptr.cfm_ltr);
501 
502         ND_PRINT(", Flags [%s]",
503                bittok2str(cfm_ltr_flag_values, "none", flags));
504 
505         ND_PRINT("\n\t  Transaction-ID 0x%08x, ttl %u",
506                GET_BE_U_4(msg_ptr.cfm_ltr->transaction_id),
507                GET_U_1(msg_ptr.cfm_ltr->ttl));
508 
509         ND_PRINT("\n\t  Replay-Action %s (%u)",
510                tok2str(cfm_ltr_replay_action_values,
511                        "Unknown",
512                        GET_U_1(msg_ptr.cfm_ltr->replay_action)),
513                GET_U_1(msg_ptr.cfm_ltr->replay_action));
514         break;
515 
516         /*
517          * No message decoder yet.
518          * Hexdump everything up until the start of the TLVs
519          */
520     case CFM_OPCODE_LBR:
521     case CFM_OPCODE_LBM:
522     default:
523         print_unknown_data(ndo, tptr, "\n\t  ",
524                            tlen -  first_tlv_offset);
525         break;
526     }
527 
528     tptr += first_tlv_offset;
529     tlen -= first_tlv_offset;
530 
531     while (tlen > 0) {
532         cfm_tlv_header = (const struct cfm_tlv_header_t *)tptr;
533 
534         /* Enough to read the tlv type ? */
535         cfm_tlv_type = GET_U_1(cfm_tlv_header->type);
536 
537         ND_PRINT("\n\t%s TLV (0x%02x)",
538                tok2str(cfm_tlv_values, "Unknown", cfm_tlv_type),
539                cfm_tlv_type);
540 
541         if (cfm_tlv_type == CFM_TLV_END) {
542             /* Length is "Not present if the Type field is 0." */
543             return;
544         }
545 
546         /* do we have the full tlv header ? */
547         if (tlen < sizeof(struct cfm_tlv_header_t))
548             goto tooshort;
549         ND_TCHECK_LEN(tptr, sizeof(struct cfm_tlv_header_t));
550         cfm_tlv_len=GET_BE_U_2(cfm_tlv_header->length);
551 
552         ND_PRINT(", length %u", cfm_tlv_len);
553 
554         tptr += sizeof(struct cfm_tlv_header_t);
555         tlen -= sizeof(struct cfm_tlv_header_t);
556         tlv_ptr = tptr;
557 
558         /* do we have the full tlv ? */
559         if (tlen < cfm_tlv_len)
560             goto tooshort;
561         ND_TCHECK_LEN(tptr, cfm_tlv_len);
562         hexdump = FALSE;
563 
564         switch(cfm_tlv_type) {
565         case CFM_TLV_PORT_STATUS:
566             if (cfm_tlv_len < 1) {
567                 ND_PRINT(" (too short, must be >= 1)");
568                 return;
569             }
570             ND_PRINT(", Status: %s (%u)",
571                    tok2str(cfm_tlv_port_status_values, "Unknown", GET_U_1(tptr)),
572                    GET_U_1(tptr));
573             break;
574 
575         case CFM_TLV_INTERFACE_STATUS:
576             if (cfm_tlv_len < 1) {
577                 ND_PRINT(" (too short, must be >= 1)");
578                 return;
579             }
580             ND_PRINT(", Status: %s (%u)",
581                    tok2str(cfm_tlv_interface_status_values, "Unknown", GET_U_1(tptr)),
582                    GET_U_1(tptr));
583             break;
584 
585         case CFM_TLV_PRIVATE:
586             if (cfm_tlv_len < 4) {
587                 ND_PRINT(" (too short, must be >= 4)");
588                 return;
589             }
590             ND_PRINT(", Vendor: %s (%u), Sub-Type %u",
591                    tok2str(oui_values,"Unknown", GET_BE_U_3(tptr)),
592                    GET_BE_U_3(tptr),
593                    GET_U_1(tptr + 3));
594             hexdump = TRUE;
595             break;
596 
597         case CFM_TLV_SENDER_ID:
598         {
599             u_int chassis_id_type, chassis_id_length;
600             u_int mgmt_addr_length;
601 
602             if (cfm_tlv_len < 1) {
603                 ND_PRINT(" (too short, must be >= 1)");
604                 goto next_tlv;
605             }
606 
607             /*
608              * Get the Chassis ID length and check it.
609              * IEEE 802.1Q-2014 Section 21.5.3.1
610              */
611             chassis_id_length = GET_U_1(tptr);
612             tptr++;
613             tlen--;
614             cfm_tlv_len--;
615 
616             if (chassis_id_length) {
617                 /*
618                  * IEEE 802.1Q-2014 Section 21.5.3.2: Chassis ID Subtype, references
619                  * IEEE 802.1AB-2005 Section 9.5.2.2, subsequently
620                  * IEEE 802.1AB-2016 Section 8.5.2.2: chassis ID subtype
621                  */
622                 if (cfm_tlv_len < 1) {
623                     ND_PRINT("\n\t  (TLV too short)");
624                     goto next_tlv;
625                 }
626                 chassis_id_type = GET_U_1(tptr);
627                 cfm_tlv_len--;
628                 ND_PRINT("\n\t  Chassis-ID Type %s (%u), Chassis-ID length %u",
629                        tok2str(cfm_tlv_senderid_chassisid_values,
630                                "Unknown",
631                                chassis_id_type),
632                        chassis_id_type,
633                        chassis_id_length);
634 
635                 if (cfm_tlv_len < chassis_id_length) {
636                     ND_PRINT("\n\t  (TLV too short)");
637                     goto next_tlv;
638                 }
639 
640                 /* IEEE 802.1Q-2014 Section 21.5.3.3: Chassis ID */
641                 switch (chassis_id_type) {
642                 case CFM_CHASSIS_ID_MAC_ADDRESS:
643                     if (chassis_id_length != MAC_ADDR_LEN) {
644                         ND_PRINT(" (invalid MAC address length)");
645                         hexdump = TRUE;
646                         break;
647                     }
648                     ND_PRINT("\n\t  MAC %s", GET_ETHERADDR_STRING(tptr + 1));
649                     break;
650 
651                 case CFM_CHASSIS_ID_NETWORK_ADDRESS:
652                     hexdump |= cfm_network_addr_print(ndo, tptr + 1, chassis_id_length);
653                     break;
654 
655                 case CFM_CHASSIS_ID_INTERFACE_NAME: /* fall through */
656                 case CFM_CHASSIS_ID_INTERFACE_ALIAS:
657                 case CFM_CHASSIS_ID_LOCAL:
658                 case CFM_CHASSIS_ID_CHASSIS_COMPONENT:
659                 case CFM_CHASSIS_ID_PORT_COMPONENT:
660                     nd_printjnp(ndo, tptr + 1, chassis_id_length);
661                     break;
662 
663                 default:
664                     hexdump = TRUE;
665                     break;
666                 }
667                 cfm_tlv_len -= chassis_id_length;
668 
669                 tptr += 1 + chassis_id_length;
670                 tlen -= 1 + chassis_id_length;
671             }
672 
673             /*
674              * Check if there is a Management Address.
675              * IEEE 802.1Q-2014 Section 21.5.3.4: Management Address Domain Length
676              * This and all subsequent fields are not present if the TLV length
677              * allows only the above fields.
678              */
679             if (cfm_tlv_len == 0) {
680                 /* No, there isn't; we're done. */
681                 break;
682             }
683 
684             /* Here mgmt_addr_length stands for the management domain length. */
685             mgmt_addr_length = GET_U_1(tptr);
686             tptr++;
687             tlen--;
688             cfm_tlv_len--;
689             ND_PRINT("\n\t  Management Address Domain Length %u", mgmt_addr_length);
690             if (mgmt_addr_length) {
691                 /* IEEE 802.1Q-2014 Section 21.5.3.5: Management Address Domain */
692                 if (cfm_tlv_len < mgmt_addr_length) {
693                     ND_PRINT("\n\t  (TLV too short)");
694                     goto next_tlv;
695                 }
696                 cfm_tlv_len -= mgmt_addr_length;
697                 /*
698                  * XXX - this is an OID; print it as such.
699                  */
700                 hex_print(ndo, "\n\t  Management Address Domain: ", tptr, mgmt_addr_length);
701                 tptr += mgmt_addr_length;
702                 tlen -= mgmt_addr_length;
703 
704                 /*
705                  * IEEE 802.1Q-2014 Section 21.5.3.6: Management Address Length
706                  * This field is present if Management Address Domain Length is not 0.
707                  */
708                 if (cfm_tlv_len < 1) {
709                     ND_PRINT(" (Management Address Length is missing)");
710                     hexdump = TRUE;
711                     break;
712                 }
713 
714                 /* Here mgmt_addr_length stands for the management address length. */
715                 mgmt_addr_length = GET_U_1(tptr);
716                 tptr++;
717                 tlen--;
718                 cfm_tlv_len--;
719                 ND_PRINT("\n\t  Management Address Length %u", mgmt_addr_length);
720                 if (mgmt_addr_length) {
721                     /* IEEE 802.1Q-2014 Section 21.5.3.7: Management Address */
722                     if (cfm_tlv_len < mgmt_addr_length) {
723                         ND_PRINT("\n\t  (TLV too short)");
724                         return;
725                     }
726                     cfm_tlv_len -= mgmt_addr_length;
727                     /*
728                      * XXX - this is a TransportDomain; print it as such.
729                      */
730                     hex_print(ndo, "\n\t  Management Address: ", tptr, mgmt_addr_length);
731                     tptr += mgmt_addr_length;
732                     tlen -= mgmt_addr_length;
733                 }
734             }
735             break;
736         }
737 
738             /*
739              * FIXME those are the defined TLVs that lack a decoder
740              * you are welcome to contribute code ;-)
741              */
742 
743         case CFM_TLV_DATA:
744         case CFM_TLV_REPLY_INGRESS:
745         case CFM_TLV_REPLY_EGRESS:
746         default:
747             hexdump = TRUE;
748             break;
749         }
750         /* do we want to see an additional hexdump ? */
751         if (hexdump || ndo->ndo_vflag > 1)
752             print_unknown_data(ndo, tlv_ptr, "\n\t  ", cfm_tlv_len);
753 
754 next_tlv:
755         tptr+=cfm_tlv_len;
756         tlen-=cfm_tlv_len;
757     }
758     return;
759 
760 tooshort:
761     ND_PRINT("\n\t\t packet is too short");
762     return;
763 
764 trunc:
765     nd_print_trunc(ndo);
766 }
767