1 /*
2 * Redistribution and use in source and binary forms, with or without
3 * modification, are permitted provided that: (1) source code
4 * distributions retain the above copyright notice and this paragraph
5 * in its entirety, and (2) distributions including binary code include
6 * the above copyright notice and this paragraph in its entirety in
7 * the documentation or other materials provided with the distribution.
8 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
9 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
10 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
11 * FOR A PARTICULAR PURPOSE.
12 *
13 * Original code by Hannes Gredler (hannes@gredler.at)
14 * and Steinar Haug (sthaug@nethelp.no)
15 */
16
17 #include <sys/cdefs.h>
18 #ifndef lint
19 __RCSID("$NetBSD: print-ldp.c,v 1.12 2024/09/02 16:15:31 christos Exp $");
20 #endif
21
22 /* \summary: Label Distribution Protocol (LDP) printer */
23
24 #include <config.h>
25
26 #include "netdissect-stdinc.h"
27
28 #include "netdissect.h"
29 #include "extract.h"
30 #include "addrtoname.h"
31
32 #include "l2vpn.h"
33 #include "af.h"
34
35
36 /*
37 * ldp common header
38 *
39 * 0 1 2 3
40 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
41 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
42 * | Version | PDU Length |
43 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
44 * | LDP Identifier |
45 * + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
46 * | |
47 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
48 *
49 */
50
51 struct ldp_common_header {
52 nd_uint16_t version;
53 nd_uint16_t pdu_length;
54 nd_ipv4 lsr_id;
55 nd_uint16_t label_space;
56 };
57
58 #define LDP_VERSION 1
59
60 /*
61 * ldp message header
62 *
63 * 0 1 2 3
64 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
65 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
66 * |U| Message Type | Message Length |
67 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
68 * | Message ID |
69 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
70 * | |
71 * + +
72 * | Mandatory Parameters |
73 * + +
74 * | |
75 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
76 * | |
77 * + +
78 * | Optional Parameters |
79 * + +
80 * | |
81 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
82 */
83
84 struct ldp_msg_header {
85 nd_uint16_t type;
86 nd_uint16_t length;
87 nd_uint32_t id;
88 };
89
90 #define LDP_MASK_MSG_TYPE(x) ((x)&0x7fff)
91 #define LDP_MASK_U_BIT(x) ((x)&0x8000)
92
93 #define LDP_MSG_NOTIF 0x0001
94 #define LDP_MSG_HELLO 0x0100
95 #define LDP_MSG_INIT 0x0200
96 #define LDP_MSG_KEEPALIVE 0x0201
97 #define LDP_MSG_ADDRESS 0x0300
98 #define LDP_MSG_ADDRESS_WITHDRAW 0x0301
99 #define LDP_MSG_LABEL_MAPPING 0x0400
100 #define LDP_MSG_LABEL_REQUEST 0x0401
101 #define LDP_MSG_LABEL_WITHDRAW 0x0402
102 #define LDP_MSG_LABEL_RELEASE 0x0403
103 #define LDP_MSG_LABEL_ABORT_REQUEST 0x0404
104
105 #define LDP_VENDOR_PRIVATE_MIN 0x3e00
106 #define LDP_VENDOR_PRIVATE_MAX 0x3eff
107 #define LDP_EXPERIMENTAL_MIN 0x3f00
108 #define LDP_EXPERIMENTAL_MAX 0x3fff
109
110 static const struct tok ldp_msg_values[] = {
111 { LDP_MSG_NOTIF, "Notification" },
112 { LDP_MSG_HELLO, "Hello" },
113 { LDP_MSG_INIT, "Initialization" },
114 { LDP_MSG_KEEPALIVE, "Keepalive" },
115 { LDP_MSG_ADDRESS, "Address" },
116 { LDP_MSG_ADDRESS_WITHDRAW, "Address Withdraw" },
117 { LDP_MSG_LABEL_MAPPING, "Label Mapping" },
118 { LDP_MSG_LABEL_REQUEST, "Label Request" },
119 { LDP_MSG_LABEL_WITHDRAW, "Label Withdraw" },
120 { LDP_MSG_LABEL_RELEASE, "Label Release" },
121 { LDP_MSG_LABEL_ABORT_REQUEST, "Label Abort Request" },
122 { 0, NULL}
123 };
124
125 #define LDP_MASK_TLV_TYPE(x) ((x)&0x3fff)
126 #define LDP_MASK_F_BIT(x) ((x)&0x4000)
127
128 #define LDP_TLV_FEC 0x0100
129 #define LDP_TLV_ADDRESS_LIST 0x0101
130 #define LDP_TLV_ADDRESS_LIST_AFNUM_LEN 2
131 #define LDP_TLV_HOP_COUNT 0x0103
132 #define LDP_TLV_PATH_VECTOR 0x0104
133 #define LDP_TLV_GENERIC_LABEL 0x0200
134 #define LDP_TLV_ATM_LABEL 0x0201
135 #define LDP_TLV_FR_LABEL 0x0202
136 #define LDP_TLV_STATUS 0x0300
137 #define LDP_TLV_EXTD_STATUS 0x0301
138 #define LDP_TLV_RETURNED_PDU 0x0302
139 #define LDP_TLV_RETURNED_MSG 0x0303
140 #define LDP_TLV_COMMON_HELLO 0x0400
141 #define LDP_TLV_IPV4_TRANSPORT_ADDR 0x0401
142 #define LDP_TLV_CONFIG_SEQ_NUMBER 0x0402
143 #define LDP_TLV_IPV6_TRANSPORT_ADDR 0x0403
144 #define LDP_TLV_COMMON_SESSION 0x0500
145 #define LDP_TLV_ATM_SESSION_PARM 0x0501
146 #define LDP_TLV_FR_SESSION_PARM 0x0502
147 #define LDP_TLV_FT_SESSION 0x0503
148 #define LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
149 #define LDP_TLV_MTU 0x0601 /* rfc 3988 */
150
151 static const struct tok ldp_tlv_values[] = {
152 { LDP_TLV_FEC, "FEC" },
153 { LDP_TLV_ADDRESS_LIST, "Address List" },
154 { LDP_TLV_HOP_COUNT, "Hop Count" },
155 { LDP_TLV_PATH_VECTOR, "Path Vector" },
156 { LDP_TLV_GENERIC_LABEL, "Generic Label" },
157 { LDP_TLV_ATM_LABEL, "ATM Label" },
158 { LDP_TLV_FR_LABEL, "Frame-Relay Label" },
159 { LDP_TLV_STATUS, "Status" },
160 { LDP_TLV_EXTD_STATUS, "Extended Status" },
161 { LDP_TLV_RETURNED_PDU, "Returned PDU" },
162 { LDP_TLV_RETURNED_MSG, "Returned Message" },
163 { LDP_TLV_COMMON_HELLO, "Common Hello Parameters" },
164 { LDP_TLV_IPV4_TRANSPORT_ADDR, "IPv4 Transport Address" },
165 { LDP_TLV_CONFIG_SEQ_NUMBER, "Configuration Sequence Number" },
166 { LDP_TLV_IPV6_TRANSPORT_ADDR, "IPv6 Transport Address" },
167 { LDP_TLV_COMMON_SESSION, "Common Session Parameters" },
168 { LDP_TLV_ATM_SESSION_PARM, "ATM Session Parameters" },
169 { LDP_TLV_FR_SESSION_PARM, "Frame-Relay Session Parameters" },
170 { LDP_TLV_FT_SESSION, "Fault-Tolerant Session Parameters" },
171 { LDP_TLV_LABEL_REQUEST_MSG_ID, "Label Request Message ID" },
172 { LDP_TLV_MTU, "MTU" },
173 { 0, NULL}
174 };
175
176 #define LDP_FEC_WILDCARD 0x01
177 #define LDP_FEC_PREFIX 0x02
178 #define LDP_FEC_HOSTADDRESS 0x03
179 /* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
180 #define LDP_FEC_MARTINI_VC 0x80
181
182 static const struct tok ldp_fec_values[] = {
183 { LDP_FEC_WILDCARD, "Wildcard" },
184 { LDP_FEC_PREFIX, "Prefix" },
185 { LDP_FEC_HOSTADDRESS, "Host address" },
186 { LDP_FEC_MARTINI_VC, "Martini VC" },
187 { 0, NULL}
188 };
189
190 #define LDP_FEC_MARTINI_IFPARM_MTU 0x01
191 #define LDP_FEC_MARTINI_IFPARM_DESC 0x03
192 #define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
193
194 static const struct tok ldp_fec_martini_ifparm_values[] = {
195 { LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
196 { LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
197 { LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
198 { 0, NULL}
199 };
200
201 /* draft-ietf-pwe3-vccv-04.txt */
202 static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
203 { 0x01, "PWE3 control word" },
204 { 0x02, "MPLS Router Alert Label" },
205 { 0x04, "MPLS inner label TTL = 1" },
206 { 0, NULL}
207 };
208
209 /* draft-ietf-pwe3-vccv-04.txt */
210 static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
211 { 0x01, "ICMP Ping" },
212 { 0x02, "LSP Ping" },
213 { 0x04, "BFD" },
214 { 0, NULL}
215 };
216
217 static u_int ldp_pdu_print(netdissect_options *, const u_char *);
218
219 /*
220 * ldp tlv header
221 *
222 * 0 1 2 3
223 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
224 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
225 * |U|F| Type | Length |
226 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
227 * | |
228 * | Value |
229 * ~ ~
230 * | |
231 * | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
232 * | |
233 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
234 */
235
236 #define TLV_TCHECK(minlen) \
237 if (tlv_tlen < minlen) { \
238 ND_PRINT(" [tlv length %u < %u]", tlv_tlen, minlen); \
239 nd_print_invalid(ndo); \
240 goto invalid; \
241 }
242
243 static u_int
ldp_tlv_print(netdissect_options * ndo,const u_char * tptr,u_int msg_tlen)244 ldp_tlv_print(netdissect_options *ndo,
245 const u_char *tptr,
246 u_int msg_tlen)
247 {
248 struct ldp_tlv_header {
249 nd_uint16_t type;
250 nd_uint16_t length;
251 };
252
253 const struct ldp_tlv_header *ldp_tlv_header;
254 u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
255 u_char fec_type;
256 u_int ui,vc_info_len, vc_info_tlv_type, vc_info_tlv_len,idx;
257 char buf[100];
258 int i;
259
260 ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
261 ND_TCHECK_SIZE(ldp_tlv_header);
262 tlv_len=GET_BE_U_2(ldp_tlv_header->length);
263 if (tlv_len + 4U > msg_tlen) {
264 ND_PRINT("\n\t\t TLV contents go past end of message");
265 return 0;
266 }
267 tlv_tlen=tlv_len;
268 tlv_type=LDP_MASK_TLV_TYPE(GET_BE_U_2(ldp_tlv_header->type));
269
270 /* FIXME vendor private / experimental check */
271 ND_PRINT("\n\t %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
272 tok2str(ldp_tlv_values,
273 "Unknown",
274 tlv_type),
275 tlv_type,
276 tlv_len,
277 LDP_MASK_U_BIT(GET_BE_U_2(ldp_tlv_header->type)) ? "continue processing" : "ignore",
278 LDP_MASK_F_BIT(GET_BE_U_2(ldp_tlv_header->type)) ? "do" : "don't");
279
280 tptr+=sizeof(struct ldp_tlv_header);
281
282 switch(tlv_type) {
283
284 case LDP_TLV_COMMON_HELLO:
285 TLV_TCHECK(4);
286 ND_PRINT("\n\t Hold Time: %us, Flags: [%s Hello%s]",
287 GET_BE_U_2(tptr),
288 (GET_BE_U_2(tptr + 2)&0x8000) ? "Targeted" : "Link",
289 (GET_BE_U_2(tptr + 2)&0x4000) ? ", Request for targeted Hellos" : "");
290 break;
291
292 case LDP_TLV_IPV4_TRANSPORT_ADDR:
293 TLV_TCHECK(4);
294 ND_PRINT("\n\t IPv4 Transport Address: %s", GET_IPADDR_STRING(tptr));
295 break;
296 case LDP_TLV_IPV6_TRANSPORT_ADDR:
297 TLV_TCHECK(16);
298 ND_PRINT("\n\t IPv6 Transport Address: %s", GET_IP6ADDR_STRING(tptr));
299 break;
300 case LDP_TLV_CONFIG_SEQ_NUMBER:
301 TLV_TCHECK(4);
302 ND_PRINT("\n\t Sequence Number: %u", GET_BE_U_4(tptr));
303 break;
304
305 case LDP_TLV_ADDRESS_LIST:
306 TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
307 af = GET_BE_U_2(tptr);
308 tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
309 tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
310 ND_PRINT("\n\t Address Family: %s, addresses",
311 tok2str(af_values, "Unknown (%u)", af));
312 switch (af) {
313 case AFNUM_INET:
314 while(tlv_tlen >= sizeof(nd_ipv4)) {
315 ND_PRINT(" %s", GET_IPADDR_STRING(tptr));
316 tlv_tlen-=sizeof(nd_ipv4);
317 tptr+=sizeof(nd_ipv4);
318 }
319 break;
320 case AFNUM_INET6:
321 while(tlv_tlen >= sizeof(nd_ipv6)) {
322 ND_PRINT(" %s", GET_IP6ADDR_STRING(tptr));
323 tlv_tlen-=sizeof(nd_ipv6);
324 tptr+=sizeof(nd_ipv6);
325 }
326 break;
327 default:
328 /* unknown AF */
329 break;
330 }
331 break;
332
333 case LDP_TLV_COMMON_SESSION:
334 TLV_TCHECK(14);
335 ND_PRINT("\n\t Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
336 GET_BE_U_2(tptr), GET_BE_U_2(tptr + 2),
337 (GET_BE_U_2(tptr + 4)&0x8000) ? "On Demand" : "Unsolicited",
338 (GET_BE_U_2(tptr + 4)&0x4000) ? "Enabled" : "Disabled"
339 );
340 ND_PRINT("\n\t Path Vector Limit %u, Max-PDU length: %u, Receiver Label-Space-ID %s:%u",
341 GET_U_1(tptr+5),
342 GET_BE_U_2(tptr+6),
343 GET_IPADDR_STRING(tptr+8),
344 GET_BE_U_2(tptr+12)
345 );
346 break;
347
348 case LDP_TLV_FEC:
349 TLV_TCHECK(1);
350 fec_type = GET_U_1(tptr);
351 ND_PRINT("\n\t %s FEC (0x%02x)",
352 tok2str(ldp_fec_values, "Unknown", fec_type),
353 fec_type);
354
355 tptr+=1;
356 tlv_tlen-=1;
357 switch(fec_type) {
358
359 case LDP_FEC_WILDCARD:
360 break;
361 case LDP_FEC_PREFIX:
362 TLV_TCHECK(2);
363 af = GET_BE_U_2(tptr);
364 tptr+=2;
365 tlv_tlen-=2;
366 if (af == AFNUM_INET) {
367 i=decode_prefix4(ndo, tptr, tlv_tlen, buf, sizeof(buf));
368 if (i == -2)
369 goto trunc;
370 if (i == -3)
371 ND_PRINT(": IPv4 prefix (goes past end of TLV)");
372 else if (i == -1)
373 ND_PRINT(": IPv4 prefix (invalid length)");
374 else
375 ND_PRINT(": IPv4 prefix %s", buf);
376 } else if (af == AFNUM_INET6) {
377 i=decode_prefix6(ndo, tptr, tlv_tlen, buf, sizeof(buf));
378 if (i == -2)
379 goto trunc;
380 if (i == -3)
381 ND_PRINT(": IPv4 prefix (goes past end of TLV)");
382 else if (i == -1)
383 ND_PRINT(": IPv6 prefix (invalid length)");
384 else
385 ND_PRINT(": IPv6 prefix %s", buf);
386 } else
387 ND_PRINT(": Address family %u prefix", af);
388 break;
389 case LDP_FEC_HOSTADDRESS:
390 break;
391 case LDP_FEC_MARTINI_VC:
392 /*
393 * We assume the type was supposed to be one of the MPLS
394 * Pseudowire Types.
395 */
396 TLV_TCHECK(7);
397 vc_info_len = GET_U_1(tptr + 2);
398
399 /*
400 * According to RFC 4908, the VC info Length field can be zero,
401 * in which case not only are there no interface parameters,
402 * there's no VC ID.
403 */
404 if (vc_info_len == 0) {
405 ND_PRINT(": %s, %scontrol word, group-ID %u, VC-info-length: %u",
406 tok2str(mpls_pw_types_values, "Unknown", GET_BE_U_2(tptr)&0x7fff),
407 GET_BE_U_2(tptr)&0x8000 ? "" : "no ",
408 GET_BE_U_4(tptr + 3),
409 vc_info_len);
410 break;
411 }
412
413 /* Make sure we have the VC ID as well */
414 TLV_TCHECK(11);
415 ND_PRINT(": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
416 tok2str(mpls_pw_types_values, "Unknown", GET_BE_U_2(tptr)&0x7fff),
417 GET_BE_U_2(tptr)&0x8000 ? "" : "no ",
418 GET_BE_U_4(tptr + 3),
419 GET_BE_U_4(tptr + 7),
420 vc_info_len);
421 if (vc_info_len < 4) {
422 /* minimum 4, for the VC ID */
423 ND_PRINT(" (invalid, < 4");
424 return(tlv_len+4); /* Type & Length fields not included */
425 }
426 vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
427
428 /* Skip past the fixed information and the VC ID */
429 tptr+=11;
430 tlv_tlen-=11;
431 TLV_TCHECK(vc_info_len);
432
433 while (vc_info_len > 2) {
434 vc_info_tlv_type = GET_U_1(tptr);
435 vc_info_tlv_len = GET_U_1(tptr + 1);
436 if (vc_info_tlv_len < 2)
437 break;
438 if (vc_info_len < vc_info_tlv_len)
439 break;
440
441 ND_PRINT("\n\t\tInterface Parameter: %s (0x%02x), len %u",
442 tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
443 vc_info_tlv_type,
444 vc_info_tlv_len);
445
446 switch(vc_info_tlv_type) {
447 case LDP_FEC_MARTINI_IFPARM_MTU:
448 ND_PRINT(": %u", GET_BE_U_2(tptr + 2));
449 break;
450
451 case LDP_FEC_MARTINI_IFPARM_DESC:
452 ND_PRINT(": ");
453 for (idx = 2; idx < vc_info_tlv_len; idx++)
454 fn_print_char(ndo, GET_U_1(tptr + idx));
455 break;
456
457 case LDP_FEC_MARTINI_IFPARM_VCCV:
458 ND_PRINT("\n\t\t Control Channels (0x%02x) = [%s]",
459 GET_U_1((tptr + 2)),
460 bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", GET_U_1((tptr + 2))));
461 ND_PRINT("\n\t\t CV Types (0x%02x) = [%s]",
462 GET_U_1((tptr + 3)),
463 bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", GET_U_1((tptr + 3))));
464 break;
465
466 default:
467 print_unknown_data(ndo, tptr+2, "\n\t\t ", vc_info_tlv_len-2);
468 break;
469 }
470
471 vc_info_len -= vc_info_tlv_len;
472 tptr += vc_info_tlv_len;
473 }
474 break;
475 }
476
477 break;
478
479 case LDP_TLV_GENERIC_LABEL:
480 TLV_TCHECK(4);
481 ND_PRINT("\n\t Label: %u", GET_BE_U_4(tptr) & 0xfffff);
482 break;
483
484 case LDP_TLV_STATUS:
485 TLV_TCHECK(8);
486 ui = GET_BE_U_4(tptr);
487 tptr+=4;
488 ND_PRINT("\n\t Status: 0x%02x, Flags: [%s and %s forward]",
489 ui&0x3fffffff,
490 ui&0x80000000 ? "Fatal error" : "Advisory Notification",
491 ui&0x40000000 ? "do" : "don't");
492 ui = GET_BE_U_4(tptr);
493 tptr+=4;
494 if (ui)
495 ND_PRINT(", causing Message ID: 0x%08x", ui);
496 break;
497
498 case LDP_TLV_FT_SESSION:
499 TLV_TCHECK(12);
500 ft_flags = GET_BE_U_2(tptr);
501 ND_PRINT("\n\t Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
502 ft_flags&0x8000 ? "" : "No ",
503 ft_flags&0x8 ? "" : "Don't ",
504 ft_flags&0x4 ? "" : "No ",
505 ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
506 ft_flags&0x1 ? "" : "Don't ");
507 /* 16 bits (FT Flags) + 16 bits (Reserved) */
508 tptr+=4;
509 ui = GET_BE_U_4(tptr);
510 if (ui)
511 ND_PRINT(", Reconnect Timeout: %ums", ui);
512 tptr+=4;
513 ui = GET_BE_U_4(tptr);
514 if (ui)
515 ND_PRINT(", Recovery Time: %ums", ui);
516 break;
517
518 case LDP_TLV_MTU:
519 TLV_TCHECK(2);
520 ND_PRINT("\n\t MTU: %u", GET_BE_U_2(tptr));
521 break;
522
523
524 /*
525 * FIXME those are the defined TLVs that lack a decoder
526 * you are welcome to contribute code ;-)
527 */
528
529 case LDP_TLV_HOP_COUNT:
530 case LDP_TLV_PATH_VECTOR:
531 case LDP_TLV_ATM_LABEL:
532 case LDP_TLV_FR_LABEL:
533 case LDP_TLV_EXTD_STATUS:
534 case LDP_TLV_RETURNED_PDU:
535 case LDP_TLV_RETURNED_MSG:
536 case LDP_TLV_ATM_SESSION_PARM:
537 case LDP_TLV_FR_SESSION_PARM:
538 case LDP_TLV_LABEL_REQUEST_MSG_ID:
539
540 default:
541 if (ndo->ndo_vflag <= 1)
542 print_unknown_data(ndo, tptr, "\n\t ", tlv_tlen);
543 break;
544 }
545 return(tlv_len+4); /* Type & Length fields not included */
546
547 trunc:
548 nd_trunc_longjmp(ndo);
549
550 invalid:
551 return(tlv_len+4); /* Type & Length fields not included */
552 }
553
554 void
ldp_print(netdissect_options * ndo,const u_char * pptr,u_int len)555 ldp_print(netdissect_options *ndo,
556 const u_char *pptr, u_int len)
557 {
558 u_int processed;
559
560 ndo->ndo_protocol = "ldp";
561 while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
562 processed = ldp_pdu_print(ndo, pptr);
563 if (processed == 0)
564 return;
565 if (len < processed) {
566 ND_PRINT(" [remaining length %u < %u]", len, processed);
567 nd_print_invalid(ndo);
568 break;
569 }
570 len -= processed;
571 pptr += processed;
572 }
573 }
574
575 static u_int
ldp_pdu_print(netdissect_options * ndo,const u_char * pptr)576 ldp_pdu_print(netdissect_options *ndo,
577 const u_char *pptr)
578 {
579 const struct ldp_common_header *ldp_com_header;
580 const struct ldp_msg_header *ldp_msg_header;
581 const u_char *tptr,*msg_tptr;
582 u_short tlen;
583 u_short pdu_len,msg_len,msg_type;
584 u_int msg_tlen;
585 int hexdump,processed;
586
587 ldp_com_header = (const struct ldp_common_header *)pptr;
588 ND_TCHECK_SIZE(ldp_com_header);
589
590 /*
591 * Sanity checking of the header.
592 */
593 if (GET_BE_U_2(ldp_com_header->version) != LDP_VERSION) {
594 ND_PRINT("%sLDP version %u packet not supported",
595 (ndo->ndo_vflag < 1) ? "" : "\n\t",
596 GET_BE_U_2(ldp_com_header->version));
597 return 0;
598 }
599
600 pdu_len = GET_BE_U_2(ldp_com_header->pdu_length);
601 if (pdu_len < sizeof(struct ldp_common_header)-4) {
602 /* length too short */
603 ND_PRINT("%sLDP, pdu-length: %u (too short, < %zu)",
604 (ndo->ndo_vflag < 1) ? "" : "\n\t",
605 pdu_len,
606 sizeof(struct ldp_common_header)-4);
607 return 0;
608 }
609
610 /* print the LSR-ID, label-space & length */
611 ND_PRINT("%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
612 (ndo->ndo_vflag < 1) ? "" : "\n\t",
613 GET_IPADDR_STRING(ldp_com_header->lsr_id),
614 GET_BE_U_2(ldp_com_header->label_space),
615 pdu_len);
616
617 /* bail out if non-verbose */
618 if (ndo->ndo_vflag < 1)
619 return 0;
620
621 /* ok they seem to want to know everything - lets fully decode it */
622 tptr = pptr + sizeof(struct ldp_common_header);
623 tlen = pdu_len - (sizeof(struct ldp_common_header)-4); /* Type & Length fields not included */
624
625 while(tlen>0) {
626 /* did we capture enough for fully decoding the msg header ? */
627 ND_TCHECK_LEN(tptr, sizeof(struct ldp_msg_header));
628
629 ldp_msg_header = (const struct ldp_msg_header *)tptr;
630 msg_len=GET_BE_U_2(ldp_msg_header->length);
631 msg_type=LDP_MASK_MSG_TYPE(GET_BE_U_2(ldp_msg_header->type));
632
633 if (msg_len < sizeof(struct ldp_msg_header)-4) {
634 /* length too short */
635 /* FIXME vendor private / experimental check */
636 ND_PRINT("\n\t %s Message (0x%04x), length: %u (too short, < %zu)",
637 tok2str(ldp_msg_values,
638 "Unknown",
639 msg_type),
640 msg_type,
641 msg_len,
642 sizeof(struct ldp_msg_header)-4);
643 return 0;
644 }
645
646 /* FIXME vendor private / experimental check */
647 ND_PRINT("\n\t %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
648 tok2str(ldp_msg_values,
649 "Unknown",
650 msg_type),
651 msg_type,
652 msg_len,
653 GET_BE_U_4(ldp_msg_header->id),
654 LDP_MASK_U_BIT(GET_BE_U_2(ldp_msg_header->type)) ? "continue processing" : "ignore");
655
656 msg_tptr=tptr+sizeof(struct ldp_msg_header);
657 msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
658
659 /* did we capture enough for fully decoding the message ? */
660 ND_TCHECK_LEN(tptr, msg_len);
661 hexdump=FALSE;
662
663 switch(msg_type) {
664
665 case LDP_MSG_NOTIF:
666 case LDP_MSG_HELLO:
667 case LDP_MSG_INIT:
668 case LDP_MSG_KEEPALIVE:
669 case LDP_MSG_ADDRESS:
670 case LDP_MSG_LABEL_MAPPING:
671 case LDP_MSG_ADDRESS_WITHDRAW:
672 case LDP_MSG_LABEL_WITHDRAW:
673 while(msg_tlen >= 4) {
674 processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
675 if (processed == 0)
676 break;
677 msg_tlen-=processed;
678 msg_tptr+=processed;
679 }
680 break;
681
682 /*
683 * FIXME those are the defined messages that lack a decoder
684 * you are welcome to contribute code ;-)
685 */
686
687 case LDP_MSG_LABEL_REQUEST:
688 case LDP_MSG_LABEL_RELEASE:
689 case LDP_MSG_LABEL_ABORT_REQUEST:
690
691 default:
692 if (ndo->ndo_vflag <= 1)
693 print_unknown_data(ndo, msg_tptr, "\n\t ", msg_tlen);
694 break;
695 }
696 /* do we want to see an additionally hexdump ? */
697 if (ndo->ndo_vflag > 1 || hexdump==TRUE)
698 print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t ",
699 msg_len);
700
701 tptr += msg_len+4;
702 tlen -= msg_len+4;
703 }
704 return pdu_len+4;
705 trunc:
706 nd_trunc_longjmp(ndo);
707 }
708