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[tcpdump] / print-ldp.c
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@juniper.net)
14 * and Steinar Haug (sthaug@nethelp.no)
15 */
16
17 #ifndef lint
18 static const char rcsid[] _U_ =
19 "@(#) $Header: /tcpdump/master/tcpdump/print-ldp.c,v 1.8 2004-06-15 09:42:42 hannes Exp $";
20 #endif
21
22 #ifdef HAVE_CONFIG_H
23 #include "config.h"
24 #endif
25
26 #include <tcpdump-stdinc.h>
27
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31
32 #include "interface.h"
33 #include "decode_prefix.h"
34 #include "extract.h"
35 #include "addrtoname.h"
36
37 #include "l2vpn.h"
38
39 /*
40 * ldp common header
41 *
42 * 0 1 2 3
43 * 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
44 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45 * | Version | PDU Length |
46 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47 * | LDP Identifier |
48 * + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49 * | |
50 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
51 *
52 */
53
54 struct ldp_common_header {
55 u_int8_t version[2];
56 u_int8_t pdu_length[2];
57 u_int8_t lsr_id[4];
58 u_int8_t label_space[2];
59 };
60
61 #define LDP_VERSION 1
62
63 /*
64 * ldp message header
65 *
66 * 0 1 2 3
67 * 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
68 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
69 * |U| Message Type | Message Length |
70 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71 * | Message ID |
72 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73 * | |
74 * + +
75 * | Mandatory Parameters |
76 * + +
77 * | |
78 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
79 * | |
80 * + +
81 * | Optional Parameters |
82 * + +
83 * | |
84 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
85 */
86
87 struct ldp_msg_header {
88 u_int8_t type[2];
89 u_int8_t length[2];
90 u_int8_t id[4];
91 };
92
93 #define LDP_MASK_MSG_TYPE(x) ((x)&0x7fff)
94 #define LDP_MASK_U_BIT(x) ((x)&0x8000)
95
96 #define LDP_MSG_NOTIF 0x0001
97 #define LDP_MSG_HELLO 0x0100
98 #define LDP_MSG_INIT 0x0200
99 #define LDP_MSG_KEEPALIVE 0x0201
100 #define LDP_MSG_ADDRESS 0x0300
101 #define LDP_MSG_ADDRESS_WITHDRAW 0x0301
102 #define LDP_MSG_LABEL_MAPPING 0x0400
103 #define LDP_MSG_LABEL_REQUEST 0x0401
104 #define LDP_MSG_LABEL_WITHDRAW 0x0402
105 #define LDP_MSG_LABEL_RELEASE 0x0403
106 #define LDP_MSG_LABEL_ABORT_REQUEST 0x0404
107
108 #define LDP_VENDOR_PRIVATE_MIN 0x3e00
109 #define LDP_VENDOR_PRIVATE_MAX 0x3eff
110 #define LDP_EXPERIMENTAL_MIN 0x3f00
111 #define LDP_EXPERIMENTAL_MAX 0x3fff
112
113 static const struct tok ldp_msg_values[] = {
114 { LDP_MSG_NOTIF, "Notification" },
115 { LDP_MSG_HELLO, "Hello" },
116 { LDP_MSG_INIT, "Initialization" },
117 { LDP_MSG_KEEPALIVE, "Keepalive" },
118 { LDP_MSG_ADDRESS, "Address" },
119 { LDP_MSG_ADDRESS_WITHDRAW, "Address Widthdraw" },
120 { LDP_MSG_LABEL_MAPPING, "Label Mapping" },
121 { LDP_MSG_LABEL_REQUEST, "Label Request" },
122 { LDP_MSG_LABEL_WITHDRAW, "Label Withdraw" },
123 { LDP_MSG_LABEL_RELEASE, "Label Release" },
124 { LDP_MSG_LABEL_ABORT_REQUEST, "Label Abort Request" },
125 { 0, NULL}
126 };
127
128 #define LDP_MASK_TLV_TYPE(x) ((x)&0x3fff)
129 #define LDP_MASK_F_BIT(x) ((x)&0x4000)
130
131 #define LDP_TLV_FEC 0x0100
132 #define LDP_TLV_ADDRESS_LIST 0x0101
133 #define LDP_TLV_HOP_COUNT 0x0103
134 #define LDP_TLV_PATH_VECTOR 0x0104
135 #define LDP_TLV_GENERIC_LABEL 0x0200
136 #define LDP_TLV_ATM_LABEL 0x0201
137 #define LDP_TLV_FR_LABEL 0x0202
138 #define LDP_TLV_STATUS 0x0300
139 #define LDP_TLV_EXTD_STATUS 0x0301
140 #define LDP_TLV_RETURNED_PDU 0x0302
141 #define LDP_TLV_RETURNED_MSG 0x0303
142 #define LDP_TLV_COMMON_HELLO 0x0400
143 #define LDP_TLV_IPV4_TRANSPORT_ADDR 0x0401
144 #define LDP_TLV_CONFIG_SEQ_NUMBER 0x0402
145 #define LDP_TLV_IPV6_TRANSPORT_ADDR 0x0403
146 #define LDP_TLV_COMMON_SESSION 0x0500
147 #define LDP_TLV_ATM_SESSION_PARM 0x0501
148 #define LDP_TLV_FR_SESSION_PARM 0x0502
149 #define LDP_TLV_FT_SESSION 0x0503
150 #define LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
151
152 static const struct tok ldp_tlv_values[] = {
153 { LDP_TLV_FEC, "FEC" },
154 { LDP_TLV_ADDRESS_LIST, "Address List" },
155 { LDP_TLV_HOP_COUNT, "Hop Count" },
156 { LDP_TLV_PATH_VECTOR, "Path Vector" },
157 { LDP_TLV_GENERIC_LABEL, "Generic Label" },
158 { LDP_TLV_ATM_LABEL, "ATM Label" },
159 { LDP_TLV_FR_LABEL, "Frame-Relay Label" },
160 { LDP_TLV_STATUS, "Status" },
161 { LDP_TLV_EXTD_STATUS, "Extended Status" },
162 { LDP_TLV_RETURNED_PDU, "Returned PDU" },
163 { LDP_TLV_RETURNED_MSG, "Returned Message" },
164 { LDP_TLV_COMMON_HELLO, "Common Hello Parameters" },
165 { LDP_TLV_IPV4_TRANSPORT_ADDR, "IPv4 Transport Address" },
166 { LDP_TLV_CONFIG_SEQ_NUMBER, "Configuration Sequence Number" },
167 { LDP_TLV_IPV6_TRANSPORT_ADDR, "IPv6 Transport Address" },
168 { LDP_TLV_COMMON_SESSION, "Common Session Parameters" },
169 { LDP_TLV_ATM_SESSION_PARM, "ATM Session Parameters" },
170 { LDP_TLV_FR_SESSION_PARM, "Frame-Relay Session Parameters" },
171 { LDP_TLV_FT_SESSION, "Fault-Tolerant Session Parameters" },
172 { LDP_TLV_LABEL_REQUEST_MSG_ID, "Label Request Message ID" },
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 draft-martini-l2circuit-trans-mpls-13.txt */
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 /* RFC1700 address family numbers, same definition in print-bgp.c */
191 #define AFNUM_INET 1
192 #define AFNUM_INET6 2
193
194 #define FALSE 0
195 #define TRUE 1
196
197 int ldp_tlv_print(register const u_char *);
198
199 /*
200 * ldp tlv header
201 *
202 * 0 1 2 3
203 * 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
204 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
205 * |U|F| Type | Length |
206 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
207 * | |
208 * | Value |
209 * ~ ~
210 * | |
211 * | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
212 * | |
213 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
214 */
215
216 int
217 ldp_tlv_print(register const u_char *tptr) {
218
219 struct ldp_tlv_header {
220 u_int8_t type[2];
221 u_int8_t length[2];
222 };
223
224 const struct ldp_tlv_header *ldp_tlv_header;
225 u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
226 u_char fec_type;
227 u_int ui;
228 char buf[100];
229 int i;
230
231 ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
232 tlv_len=EXTRACT_16BITS(ldp_tlv_header->length);
233 tlv_tlen=tlv_len;
234 tlv_type=LDP_MASK_TLV_TYPE(EXTRACT_16BITS(ldp_tlv_header->type));
235
236 /* FIXME vendor private / experimental check */
237 printf("\n\t %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
238 tok2str(ldp_tlv_values,
239 "Unknown",
240 tlv_type),
241 tlv_type,
242 tlv_len,
243 LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "continue processing" : "ignore",
244 LDP_MASK_F_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "do" : "don't");
245
246 tptr+=sizeof(struct ldp_tlv_header);
247
248 switch(tlv_type) {
249
250 case LDP_TLV_COMMON_HELLO:
251 printf("\n\t Hold Time: %us, Flags: [%s Hello%s]",
252 EXTRACT_16BITS(tptr),
253 (EXTRACT_16BITS(tptr+2)&0x8000) ? "Targeted" : "Link",
254 (EXTRACT_16BITS(tptr+2)&0x4000) ? ", Request for targeted Hellos" : "");
255 break;
256
257 case LDP_TLV_IPV4_TRANSPORT_ADDR:
258 printf("\n\t IPv4 Transport Address: %s", ipaddr_string(tptr));
259 break;
260 #ifdef INET6
261 case LDP_TLV_IPV6_TRANSPORT_ADDR:
262 printf("\n\t IPv6 Transport Address: %s", ip6addr_string(tptr));
263 break;
264 #endif
265 case LDP_TLV_CONFIG_SEQ_NUMBER:
266 printf("\n\t Sequence Number: %u", EXTRACT_32BITS(tptr));
267 break;
268
269 case LDP_TLV_ADDRESS_LIST:
270 af = EXTRACT_16BITS(tptr);
271 tptr+=2;
272 printf("\n\t Adress Family: ");
273 if (af == AFNUM_INET) {
274 printf("IPv4, addresses:");
275 for (i=0; i<(tlv_tlen-2)/4; i++) {
276 printf(" %s",ipaddr_string(tptr));
277 tptr+=4;
278 }
279 }
280 #ifdef INET6
281 else if (af == AFNUM_INET6) {
282 printf("IPv6, addresses:");
283 for (i=0; i<(tlv_tlen-2)/16; i++) {
284 printf(" %s",ip6addr_string(tptr));
285 tptr+=16;
286 }
287 }
288 #endif
289 break;
290
291 case LDP_TLV_COMMON_SESSION:
292 printf("\n\t Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
293 EXTRACT_16BITS(tptr), EXTRACT_16BITS(tptr+2),
294 (EXTRACT_16BITS(tptr+6)&0x8000) ? "On Demand" : "Unsolicited",
295 (EXTRACT_16BITS(tptr+6)&0x4000) ? "Enabled" : "Disabled"
296 );
297 break;
298
299 case LDP_TLV_FEC:
300 fec_type = *tptr;
301 printf("\n\t %s FEC (0x%02x)",
302 tok2str(ldp_fec_values, "Unknown", fec_type),
303 fec_type);
304
305 tptr+=1;
306 switch(fec_type) {
307
308 case LDP_FEC_WILDCARD:
309 break;
310 case LDP_FEC_PREFIX:
311 af = EXTRACT_16BITS(tptr);
312 tptr+=2;
313 if (af == AFNUM_INET) {
314 i=decode_prefix4(tptr,buf,sizeof(buf));
315 printf(": IPv4 prefix %s",buf);
316 }
317 #ifdef INET6
318 else if (af == AFNUM_INET6) {
319 i=decode_prefix6(tptr,buf,sizeof(buf));
320 printf(": IPv6 prefix %s",buf);
321 }
322 #endif
323 break;
324 case LDP_FEC_HOSTADDRESS:
325 break;
326 case LDP_FEC_MARTINI_VC:
327 printf(": %s, %scontrol word, VC %u",
328 tok2str(l2vpn_encaps_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
329 EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
330 EXTRACT_32BITS(tptr+7));
331 break;
332 }
333
334 break;
335
336 case LDP_TLV_GENERIC_LABEL:
337 printf("\n\t Label: %u", EXTRACT_32BITS(tptr) & 0xfffff);
338 break;
339
340 case LDP_TLV_STATUS:
341 ui = EXTRACT_32BITS(tptr);
342 tptr+=4;
343 printf("\n\t Status: 0x%02x, Flags: [%s and %s forward]",
344 ui&0x3fffffff,
345 ui&0x80000000 ? "Fatal error" : "Advisory Notification",
346 ui&0x40000000 ? "do" : "don't");
347 ui = EXTRACT_32BITS(tptr);
348 tptr+=4;
349 if (ui)
350 printf(", causing Message ID: 0x%08x", ui);
351 break;
352
353 case LDP_TLV_FT_SESSION:
354 ft_flags = EXTRACT_16BITS(tptr);
355 printf("\n\t Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
356 ft_flags&0x8000 ? "" : "No ",
357 ft_flags&0x8 ? "" : "Don't ",
358 ft_flags&0x4 ? "" : "No ",
359 ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
360 ft_flags&0x1 ? "" : "Don't ");
361 tptr+=4;
362 ui = EXTRACT_32BITS(tptr);
363 if (ui)
364 printf(", Reconnect Timeout: %ums", ui);
365 tptr+=4;
366 ui = EXTRACT_32BITS(tptr);
367 if (ui)
368 printf(", Recovery Time: %ums", ui);
369 break;
370
371
372 /*
373 * FIXME those are the defined TLVs that lack a decoder
374 * you are welcome to contribute code ;-)
375 */
376
377 case LDP_TLV_HOP_COUNT:
378 case LDP_TLV_PATH_VECTOR:
379 case LDP_TLV_ATM_LABEL:
380 case LDP_TLV_FR_LABEL:
381 case LDP_TLV_EXTD_STATUS:
382 case LDP_TLV_RETURNED_PDU:
383 case LDP_TLV_RETURNED_MSG:
384 case LDP_TLV_ATM_SESSION_PARM:
385 case LDP_TLV_FR_SESSION_PARM:
386 case LDP_TLV_LABEL_REQUEST_MSG_ID:
387
388 default:
389 if (vflag <= 1)
390 print_unknown_data(tptr,"\n\t ",tlv_tlen);
391 break;
392 }
393 return(tlv_len+4); /* Type & Length fields not included */
394 }
395
396 void
397 ldp_print(register const u_char *pptr, register u_int len) {
398
399 const struct ldp_common_header *ldp_com_header;
400 const struct ldp_msg_header *ldp_msg_header;
401 const u_char *tptr,*msg_tptr;
402 u_short tlen;
403 u_short msg_len,msg_type,msg_tlen;
404 int hexdump,processed;
405
406 tptr=pptr;
407 ldp_com_header = (const struct ldp_common_header *)pptr;
408 TCHECK(*ldp_com_header);
409
410 /*
411 * Sanity checking of the header.
412 */
413 if (EXTRACT_16BITS(&ldp_com_header->version) != LDP_VERSION) {
414 printf("LDP version %u packet not supported",
415 EXTRACT_16BITS(&ldp_com_header->version));
416 return;
417 }
418
419 /* print the LSR-ID, label-space & length */
420 printf("%sLDP, Label-Space-ID: %s:%u, length: %u",
421 (vflag < 1) ? "" : "\n\t",
422 ipaddr_string(&ldp_com_header->lsr_id),
423 EXTRACT_16BITS(&ldp_com_header->label_space),
424 len);
425
426 /* bail out if non-verbose */
427 if (vflag < 1)
428 return;
429
430 /* ok they seem to want to know everything - lets fully decode it */
431 tlen=EXTRACT_16BITS(ldp_com_header->pdu_length);
432
433 tptr += sizeof(const struct ldp_common_header);
434 tlen -= sizeof(const struct ldp_common_header)-4; /* Type & Length fields not included */
435
436 while(tlen>0) {
437 /* did we capture enough for fully decoding the msg header ? */
438 if (!TTEST2(*tptr, sizeof(struct ldp_msg_header)))
439 goto trunc;
440
441 ldp_msg_header = (const struct ldp_msg_header *)tptr;
442 msg_len=EXTRACT_16BITS(ldp_msg_header->length);
443 msg_type=LDP_MASK_MSG_TYPE(EXTRACT_16BITS(ldp_msg_header->type));
444
445 /* FIXME vendor private / experimental check */
446 printf("\n\t %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
447 tok2str(ldp_msg_values,
448 "Unknown",
449 msg_type),
450 msg_type,
451 msg_len,
452 EXTRACT_32BITS(&ldp_msg_header->id),
453 LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_msg_header->type)) ? "continue processing" : "ignore");
454
455 msg_tptr=tptr+sizeof(struct ldp_msg_header);
456 msg_tlen=msg_len-sizeof(struct ldp_msg_header)+4; /* Type & Length fields not included */
457
458 /* did we capture enough for fully decoding the message ? */
459 if (!TTEST2(*tptr, msg_len))
460 goto trunc;
461 hexdump=FALSE;
462
463 switch(msg_type) {
464
465 case LDP_MSG_NOTIF:
466 case LDP_MSG_HELLO:
467 case LDP_MSG_INIT:
468 case LDP_MSG_KEEPALIVE:
469 case LDP_MSG_ADDRESS:
470 case LDP_MSG_LABEL_MAPPING:
471 while(msg_tlen >= 4) {
472 processed = ldp_tlv_print(msg_tptr);
473 if (processed == 0)
474 break;
475 msg_tlen-=processed;
476 msg_tptr+=processed;
477 }
478 break;
479
480 /*
481 * FIXME those are the defined messages that lack a decoder
482 * you are welcome to contribute code ;-)
483 */
484
485 case LDP_MSG_ADDRESS_WITHDRAW:
486 case LDP_MSG_LABEL_REQUEST:
487 case LDP_MSG_LABEL_WITHDRAW:
488 case LDP_MSG_LABEL_RELEASE:
489 case LDP_MSG_LABEL_ABORT_REQUEST:
490
491 default:
492 if (vflag <= 1)
493 print_unknown_data(msg_tptr,"\n\t ",msg_tlen);
494 break;
495 }
496 /* do we want to see an additionally hexdump ? */
497 if (vflag > 1 || hexdump==TRUE)
498 print_unknown_data(tptr+sizeof(sizeof(struct ldp_msg_header)),"\n\t ",
499 msg_len);
500
501 tptr += msg_len+4;
502 tlen -= msg_len+4;
503 }
504 return;
505 trunc:
506 printf("\n\t\t packet exceeded snapshot");
507 }
508