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