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Handle very large -f files by rejecting them.
[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@gredler.at)
14 * and Steinar Haug (sthaug@nethelp.no)
15 */
16
17 /* \summary: Label Distribution Protocol (LDP) printer */
18
19 #ifdef HAVE_CONFIG_H
20 #include "config.h"
21 #endif
22
23 #include <netdissect-stdinc.h>
24
25 #include "netdissect.h"
26 #include "extract.h"
27 #include "addrtoname.h"
28
29 #include "l2vpn.h"
30 #include "af.h"
31
32 static const char tstr[] = " [|LDP]";
33
34 /*
35 * ldp common header
36 *
37 * 0 1 2 3
38 * 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
39 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
40 * | Version | PDU Length |
41 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
42 * | LDP Identifier |
43 * + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
44 * | |
45 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
46 *
47 */
48
49 struct ldp_common_header {
50 uint8_t version[2];
51 uint8_t pdu_length[2];
52 uint8_t lsr_id[4];
53 uint8_t label_space[2];
54 };
55
56 #define LDP_VERSION 1
57
58 /*
59 * ldp message header
60 *
61 * 0 1 2 3
62 * 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
63 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
64 * |U| Message Type | Message Length |
65 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
66 * | Message ID |
67 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
68 * | |
69 * + +
70 * | Mandatory Parameters |
71 * + +
72 * | |
73 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
74 * | |
75 * + +
76 * | Optional Parameters |
77 * + +
78 * | |
79 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
80 */
81
82 struct ldp_msg_header {
83 uint8_t type[2];
84 uint8_t length[2];
85 uint8_t id[4];
86 };
87
88 #define LDP_MASK_MSG_TYPE(x) ((x)&0x7fff)
89 #define LDP_MASK_U_BIT(x) ((x)&0x8000)
90
91 #define LDP_MSG_NOTIF 0x0001
92 #define LDP_MSG_HELLO 0x0100
93 #define LDP_MSG_INIT 0x0200
94 #define LDP_MSG_KEEPALIVE 0x0201
95 #define LDP_MSG_ADDRESS 0x0300
96 #define LDP_MSG_ADDRESS_WITHDRAW 0x0301
97 #define LDP_MSG_LABEL_MAPPING 0x0400
98 #define LDP_MSG_LABEL_REQUEST 0x0401
99 #define LDP_MSG_LABEL_WITHDRAW 0x0402
100 #define LDP_MSG_LABEL_RELEASE 0x0403
101 #define LDP_MSG_LABEL_ABORT_REQUEST 0x0404
102
103 #define LDP_VENDOR_PRIVATE_MIN 0x3e00
104 #define LDP_VENDOR_PRIVATE_MAX 0x3eff
105 #define LDP_EXPERIMENTAL_MIN 0x3f00
106 #define LDP_EXPERIMENTAL_MAX 0x3fff
107
108 static const struct tok ldp_msg_values[] = {
109 { LDP_MSG_NOTIF, "Notification" },
110 { LDP_MSG_HELLO, "Hello" },
111 { LDP_MSG_INIT, "Initialization" },
112 { LDP_MSG_KEEPALIVE, "Keepalive" },
113 { LDP_MSG_ADDRESS, "Address" },
114 { LDP_MSG_ADDRESS_WITHDRAW, "Address Withdraw" },
115 { LDP_MSG_LABEL_MAPPING, "Label Mapping" },
116 { LDP_MSG_LABEL_REQUEST, "Label Request" },
117 { LDP_MSG_LABEL_WITHDRAW, "Label Withdraw" },
118 { LDP_MSG_LABEL_RELEASE, "Label Release" },
119 { LDP_MSG_LABEL_ABORT_REQUEST, "Label Abort Request" },
120 { 0, NULL}
121 };
122
123 #define LDP_MASK_TLV_TYPE(x) ((x)&0x3fff)
124 #define LDP_MASK_F_BIT(x) ((x)&0x4000)
125
126 #define LDP_TLV_FEC 0x0100
127 #define LDP_TLV_ADDRESS_LIST 0x0101
128 #define LDP_TLV_ADDRESS_LIST_AFNUM_LEN 2
129 #define LDP_TLV_HOP_COUNT 0x0103
130 #define LDP_TLV_PATH_VECTOR 0x0104
131 #define LDP_TLV_GENERIC_LABEL 0x0200
132 #define LDP_TLV_ATM_LABEL 0x0201
133 #define LDP_TLV_FR_LABEL 0x0202
134 #define LDP_TLV_STATUS 0x0300
135 #define LDP_TLV_EXTD_STATUS 0x0301
136 #define LDP_TLV_RETURNED_PDU 0x0302
137 #define LDP_TLV_RETURNED_MSG 0x0303
138 #define LDP_TLV_COMMON_HELLO 0x0400
139 #define LDP_TLV_IPV4_TRANSPORT_ADDR 0x0401
140 #define LDP_TLV_CONFIG_SEQ_NUMBER 0x0402
141 #define LDP_TLV_IPV6_TRANSPORT_ADDR 0x0403
142 #define LDP_TLV_COMMON_SESSION 0x0500
143 #define LDP_TLV_ATM_SESSION_PARM 0x0501
144 #define LDP_TLV_FR_SESSION_PARM 0x0502
145 #define LDP_TLV_FT_SESSION 0x0503
146 #define LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
147 #define LDP_TLV_MTU 0x0601 /* rfc 3988 */
148
149 static const struct tok ldp_tlv_values[] = {
150 { LDP_TLV_FEC, "FEC" },
151 { LDP_TLV_ADDRESS_LIST, "Address List" },
152 { LDP_TLV_HOP_COUNT, "Hop Count" },
153 { LDP_TLV_PATH_VECTOR, "Path Vector" },
154 { LDP_TLV_GENERIC_LABEL, "Generic Label" },
155 { LDP_TLV_ATM_LABEL, "ATM Label" },
156 { LDP_TLV_FR_LABEL, "Frame-Relay Label" },
157 { LDP_TLV_STATUS, "Status" },
158 { LDP_TLV_EXTD_STATUS, "Extended Status" },
159 { LDP_TLV_RETURNED_PDU, "Returned PDU" },
160 { LDP_TLV_RETURNED_MSG, "Returned Message" },
161 { LDP_TLV_COMMON_HELLO, "Common Hello Parameters" },
162 { LDP_TLV_IPV4_TRANSPORT_ADDR, "IPv4 Transport Address" },
163 { LDP_TLV_CONFIG_SEQ_NUMBER, "Configuration Sequence Number" },
164 { LDP_TLV_IPV6_TRANSPORT_ADDR, "IPv6 Transport Address" },
165 { LDP_TLV_COMMON_SESSION, "Common Session Parameters" },
166 { LDP_TLV_ATM_SESSION_PARM, "ATM Session Parameters" },
167 { LDP_TLV_FR_SESSION_PARM, "Frame-Relay Session Parameters" },
168 { LDP_TLV_FT_SESSION, "Fault-Tolerant Session Parameters" },
169 { LDP_TLV_LABEL_REQUEST_MSG_ID, "Label Request Message ID" },
170 { LDP_TLV_MTU, "MTU" },
171 { 0, NULL}
172 };
173
174 #define LDP_FEC_WILDCARD 0x01
175 #define LDP_FEC_PREFIX 0x02
176 #define LDP_FEC_HOSTADDRESS 0x03
177 /* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
178 #define LDP_FEC_MARTINI_VC 0x80
179
180 static const struct tok ldp_fec_values[] = {
181 { LDP_FEC_WILDCARD, "Wildcard" },
182 { LDP_FEC_PREFIX, "Prefix" },
183 { LDP_FEC_HOSTADDRESS, "Host address" },
184 { LDP_FEC_MARTINI_VC, "Martini VC" },
185 { 0, NULL}
186 };
187
188 #define LDP_FEC_MARTINI_IFPARM_MTU 0x01
189 #define LDP_FEC_MARTINI_IFPARM_DESC 0x03
190 #define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
191
192 static const struct tok ldp_fec_martini_ifparm_values[] = {
193 { LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
194 { LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
195 { LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
196 { 0, NULL}
197 };
198
199 /* draft-ietf-pwe3-vccv-04.txt */
200 static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
201 { 0x01, "PWE3 control word" },
202 { 0x02, "MPLS Router Alert Label" },
203 { 0x04, "MPLS inner label TTL = 1" },
204 { 0, NULL}
205 };
206
207 /* draft-ietf-pwe3-vccv-04.txt */
208 static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
209 { 0x01, "ICMP Ping" },
210 { 0x02, "LSP Ping" },
211 { 0x04, "BFD" },
212 { 0, NULL}
213 };
214
215 static u_int ldp_pdu_print(netdissect_options *, register const u_char *);
216
217 /*
218 * ldp tlv header
219 *
220 * 0 1 2 3
221 * 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
222 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
223 * |U|F| Type | Length |
224 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
225 * | |
226 * | Value |
227 * ~ ~
228 * | |
229 * | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
230 * | |
231 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
232 */
233
234 #define TLV_TCHECK(minlen) \
235 ND_TCHECK2(*tptr, minlen); if (tlv_tlen < minlen) goto badtlv;
236
237 static int
238 ldp_tlv_print(netdissect_options *ndo,
239 register const u_char *tptr,
240 u_short msg_tlen)
241 {
242 struct ldp_tlv_header {
243 uint8_t type[2];
244 uint8_t length[2];
245 };
246
247 const struct ldp_tlv_header *ldp_tlv_header;
248 u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
249 u_char fec_type;
250 u_int ui,vc_info_len, vc_info_tlv_type, vc_info_tlv_len,idx;
251 char buf[100];
252 int i;
253
254 ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
255 ND_TCHECK(*ldp_tlv_header);
256 tlv_len=EXTRACT_16BITS(ldp_tlv_header->length);
257 if (tlv_len + 4 > msg_tlen) {
258 ND_PRINT((ndo, "\n\t\t TLV contents go past end of message"));
259 return 0;
260 }
261 tlv_tlen=tlv_len;
262 tlv_type=LDP_MASK_TLV_TYPE(EXTRACT_16BITS(ldp_tlv_header->type));
263
264 /* FIXME vendor private / experimental check */
265 ND_PRINT((ndo, "\n\t %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
266 tok2str(ldp_tlv_values,
267 "Unknown",
268 tlv_type),
269 tlv_type,
270 tlv_len,
271 LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "continue processing" : "ignore",
272 LDP_MASK_F_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "do" : "don't"));
273
274 tptr+=sizeof(struct ldp_tlv_header);
275
276 switch(tlv_type) {
277
278 case LDP_TLV_COMMON_HELLO:
279 TLV_TCHECK(4);
280 ND_PRINT((ndo, "\n\t Hold Time: %us, Flags: [%s Hello%s]",
281 EXTRACT_16BITS(tptr),
282 (EXTRACT_16BITS(tptr+2)&0x8000) ? "Targeted" : "Link",
283 (EXTRACT_16BITS(tptr+2)&0x4000) ? ", Request for targeted Hellos" : ""));
284 break;
285
286 case LDP_TLV_IPV4_TRANSPORT_ADDR:
287 TLV_TCHECK(4);
288 ND_PRINT((ndo, "\n\t IPv4 Transport Address: %s", ipaddr_string(ndo, tptr)));
289 break;
290 case LDP_TLV_IPV6_TRANSPORT_ADDR:
291 TLV_TCHECK(16);
292 ND_PRINT((ndo, "\n\t IPv6 Transport Address: %s", ip6addr_string(ndo, tptr)));
293 break;
294 case LDP_TLV_CONFIG_SEQ_NUMBER:
295 TLV_TCHECK(4);
296 ND_PRINT((ndo, "\n\t Sequence Number: %u", EXTRACT_32BITS(tptr)));
297 break;
298
299 case LDP_TLV_ADDRESS_LIST:
300 TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
301 af = EXTRACT_16BITS(tptr);
302 tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
303 tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
304 ND_PRINT((ndo, "\n\t Address Family: %s, addresses",
305 tok2str(af_values, "Unknown (%u)", af)));
306 switch (af) {
307 case AFNUM_INET:
308 while(tlv_tlen >= sizeof(struct in_addr)) {
309 ND_TCHECK2(*tptr, sizeof(struct in_addr));
310 ND_PRINT((ndo, " %s", ipaddr_string(ndo, tptr)));
311 tlv_tlen-=sizeof(struct in_addr);
312 tptr+=sizeof(struct in_addr);
313 }
314 break;
315 case AFNUM_INET6:
316 while(tlv_tlen >= sizeof(struct in6_addr)) {
317 ND_TCHECK2(*tptr, sizeof(struct in6_addr));
318 ND_PRINT((ndo, " %s", ip6addr_string(ndo, tptr)));
319 tlv_tlen-=sizeof(struct in6_addr);
320 tptr+=sizeof(struct in6_addr);
321 }
322 break;
323 default:
324 /* unknown AF */
325 break;
326 }
327 break;
328
329 case LDP_TLV_COMMON_SESSION:
330 TLV_TCHECK(8);
331 ND_PRINT((ndo, "\n\t Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
332 EXTRACT_16BITS(tptr), EXTRACT_16BITS(tptr+2),
333 (EXTRACT_16BITS(tptr+6)&0x8000) ? "On Demand" : "Unsolicited",
334 (EXTRACT_16BITS(tptr+6)&0x4000) ? "Enabled" : "Disabled"
335 ));
336 break;
337
338 case LDP_TLV_FEC:
339 TLV_TCHECK(1);
340 fec_type = *tptr;
341 ND_PRINT((ndo, "\n\t %s FEC (0x%02x)",
342 tok2str(ldp_fec_values, "Unknown", fec_type),
343 fec_type));
344
345 tptr+=1;
346 tlv_tlen-=1;
347 switch(fec_type) {
348
349 case LDP_FEC_WILDCARD:
350 break;
351 case LDP_FEC_PREFIX:
352 TLV_TCHECK(2);
353 af = EXTRACT_16BITS(tptr);
354 tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
355 tlv_tlen-=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
356 if (af == AFNUM_INET) {
357 i=decode_prefix4(ndo, tptr, tlv_tlen, buf, sizeof(buf));
358 if (i == -2)
359 goto trunc;
360 if (i == -3)
361 ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
362 else if (i == -1)
363 ND_PRINT((ndo, ": IPv4 prefix (invalid length)"));
364 else
365 ND_PRINT((ndo, ": IPv4 prefix %s", buf));
366 }
367 else if (af == AFNUM_INET6) {
368 i=decode_prefix6(ndo, tptr, tlv_tlen, buf, sizeof(buf));
369 if (i == -2)
370 goto trunc;
371 if (i == -3)
372 ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
373 else if (i == -1)
374 ND_PRINT((ndo, ": IPv6 prefix (invalid length)"));
375 else
376 ND_PRINT((ndo, ": IPv6 prefix %s", buf));
377 }
378 else
379 ND_PRINT((ndo, ": Address family %u prefix", af));
380 break;
381 case LDP_FEC_HOSTADDRESS:
382 break;
383 case LDP_FEC_MARTINI_VC:
384 /*
385 * We assume the type was supposed to be one of the MPLS
386 * Pseudowire Types.
387 */
388 TLV_TCHECK(7);
389 vc_info_len = *(tptr+2);
390
391 /*
392 * According to RFC 4908, the VC info Length field can be zero,
393 * in which case not only are there no interface parameters,
394 * there's no VC ID.
395 */
396 if (vc_info_len == 0) {
397 ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-info-length: %u",
398 tok2str(mpls_pw_types_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
399 EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
400 EXTRACT_32BITS(tptr+3),
401 vc_info_len));
402 break;
403 }
404
405 /* Make sure we have the VC ID as well */
406 TLV_TCHECK(11);
407 ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
408 tok2str(mpls_pw_types_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
409 EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
410 EXTRACT_32BITS(tptr+3),
411 EXTRACT_32BITS(tptr+7),
412 vc_info_len));
413 if (vc_info_len < 4) {
414 /* minimum 4, for the VC ID */
415 ND_PRINT((ndo, " (invalid, < 4"));
416 return(tlv_len+4); /* Type & Length fields not included */
417 }
418 vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
419
420 /* Skip past the fixed information and the VC ID */
421 tptr+=11;
422 tlv_tlen-=11;
423 TLV_TCHECK(vc_info_len);
424
425 while (vc_info_len > 2) {
426 vc_info_tlv_type = *tptr;
427 vc_info_tlv_len = *(tptr+1);
428 if (vc_info_tlv_len < 2)
429 break;
430 if (vc_info_len < vc_info_tlv_len)
431 break;
432
433 ND_PRINT((ndo, "\n\t\tInterface Parameter: %s (0x%02x), len %u",
434 tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
435 vc_info_tlv_type,
436 vc_info_tlv_len));
437
438 switch(vc_info_tlv_type) {
439 case LDP_FEC_MARTINI_IFPARM_MTU:
440 ND_TCHECK_16BITS(tptr + 2);
441 ND_PRINT((ndo, ": %u", EXTRACT_16BITS(tptr+2)));
442 break;
443
444 case LDP_FEC_MARTINI_IFPARM_DESC:
445 ND_PRINT((ndo, ": "));
446 for (idx = 2; idx < vc_info_tlv_len; idx++) {
447 ND_TCHECK_8BITS(tptr + idx);
448 safeputchar(ndo, *(tptr + idx));
449 }
450 break;
451
452 case LDP_FEC_MARTINI_IFPARM_VCCV:
453 ND_TCHECK_8BITS(tptr + 2);
454 ND_PRINT((ndo, "\n\t\t Control Channels (0x%02x) = [%s]",
455 *(tptr+2),
456 bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", *(tptr+2))));
457 ND_TCHECK_8BITS(tptr + 3);
458 ND_PRINT((ndo, "\n\t\t CV Types (0x%02x) = [%s]",
459 *(tptr+3),
460 bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", *(tptr+3))));
461 break;
462
463 default:
464 print_unknown_data(ndo, tptr+2, "\n\t\t ", vc_info_tlv_len-2);
465 break;
466 }
467
468 vc_info_len -= vc_info_tlv_len;
469 tptr += vc_info_tlv_len;
470 }
471 break;
472 }
473
474 break;
475
476 case LDP_TLV_GENERIC_LABEL:
477 TLV_TCHECK(4);
478 ND_PRINT((ndo, "\n\t Label: %u", EXTRACT_32BITS(tptr) & 0xfffff));
479 break;
480
481 case LDP_TLV_STATUS:
482 TLV_TCHECK(8);
483 ui = EXTRACT_32BITS(tptr);
484 tptr+=4;
485 ND_PRINT((ndo, "\n\t Status: 0x%02x, Flags: [%s and %s forward]",
486 ui&0x3fffffff,
487 ui&0x80000000 ? "Fatal error" : "Advisory Notification",
488 ui&0x40000000 ? "do" : "don't"));
489 ui = EXTRACT_32BITS(tptr);
490 tptr+=4;
491 if (ui)
492 ND_PRINT((ndo, ", causing Message ID: 0x%08x", ui));
493 break;
494
495 case LDP_TLV_FT_SESSION:
496 TLV_TCHECK(12);
497 ft_flags = EXTRACT_16BITS(tptr);
498 ND_PRINT((ndo, "\n\t Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
499 ft_flags&0x8000 ? "" : "No ",
500 ft_flags&0x8 ? "" : "Don't ",
501 ft_flags&0x4 ? "" : "No ",
502 ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
503 ft_flags&0x1 ? "" : "Don't "));
504 /* 16 bits (FT Flags) + 16 bits (Reserved) */
505 tptr+=4;
506 ui = EXTRACT_32BITS(tptr);
507 if (ui)
508 ND_PRINT((ndo, ", Reconnect Timeout: %ums", ui));
509 tptr+=4;
510 ui = EXTRACT_32BITS(tptr);
511 if (ui)
512 ND_PRINT((ndo, ", Recovery Time: %ums", ui));
513 break;
514
515 case LDP_TLV_MTU:
516 TLV_TCHECK(2);
517 ND_PRINT((ndo, "\n\t MTU: %u", EXTRACT_16BITS(tptr)));
518 break;
519
520
521 /*
522 * FIXME those are the defined TLVs that lack a decoder
523 * you are welcome to contribute code ;-)
524 */
525
526 case LDP_TLV_HOP_COUNT:
527 case LDP_TLV_PATH_VECTOR:
528 case LDP_TLV_ATM_LABEL:
529 case LDP_TLV_FR_LABEL:
530 case LDP_TLV_EXTD_STATUS:
531 case LDP_TLV_RETURNED_PDU:
532 case LDP_TLV_RETURNED_MSG:
533 case LDP_TLV_ATM_SESSION_PARM:
534 case LDP_TLV_FR_SESSION_PARM:
535 case LDP_TLV_LABEL_REQUEST_MSG_ID:
536
537 default:
538 if (ndo->ndo_vflag <= 1)
539 print_unknown_data(ndo, tptr, "\n\t ", tlv_tlen);
540 break;
541 }
542 return(tlv_len+4); /* Type & Length fields not included */
543
544 trunc:
545 ND_PRINT((ndo, "%s", tstr));
546 return 0;
547
548 badtlv:
549 ND_PRINT((ndo, "\n\t\t TLV contents go past end of TLV"));
550 return(tlv_len+4); /* Type & Length fields not included */
551 }
552
553 void
554 ldp_print(netdissect_options *ndo,
555 register const u_char *pptr, register u_int len)
556 {
557 u_int processed;
558 while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
559 processed = ldp_pdu_print(ndo, pptr);
560 if (processed == 0)
561 return;
562 if (len < processed) {
563 ND_PRINT((ndo, " [remaining length %u < %u]", len, processed));
564 ND_PRINT((ndo, "%s", istr));
565 break;
566
567 }
568 len -= processed;
569 pptr += processed;
570 }
571 }
572
573 static u_int
574 ldp_pdu_print(netdissect_options *ndo,
575 register const u_char *pptr)
576 {
577 const struct ldp_common_header *ldp_com_header;
578 const struct ldp_msg_header *ldp_msg_header;
579 const u_char *tptr,*msg_tptr;
580 u_short tlen;
581 u_short pdu_len,msg_len,msg_type,msg_tlen;
582 int hexdump,processed;
583
584 ldp_com_header = (const struct ldp_common_header *)pptr;
585 ND_TCHECK(*ldp_com_header);
586
587 /*
588 * Sanity checking of the header.
589 */
590 if (EXTRACT_16BITS(&ldp_com_header->version) != LDP_VERSION) {
591 ND_PRINT((ndo, "%sLDP version %u packet not supported",
592 (ndo->ndo_vflag < 1) ? "" : "\n\t",
593 EXTRACT_16BITS(&ldp_com_header->version)));
594 return 0;
595 }
596
597 pdu_len = EXTRACT_16BITS(&ldp_com_header->pdu_length);
598 if (pdu_len < sizeof(const struct ldp_common_header)-4) {
599 /* length too short */
600 ND_PRINT((ndo, "%sLDP, pdu-length: %u (too short, < %u)",
601 (ndo->ndo_vflag < 1) ? "" : "\n\t",
602 pdu_len,
603 (u_int)(sizeof(const struct ldp_common_header)-4)));
604 return 0;
605 }
606
607 /* print the LSR-ID, label-space & length */
608 ND_PRINT((ndo, "%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
609 (ndo->ndo_vflag < 1) ? "" : "\n\t",
610 ipaddr_string(ndo, &ldp_com_header->lsr_id),
611 EXTRACT_16BITS(&ldp_com_header->label_space),
612 pdu_len));
613
614 /* bail out if non-verbose */
615 if (ndo->ndo_vflag < 1)
616 return 0;
617
618 /* ok they seem to want to know everything - lets fully decode it */
619 tptr = pptr + sizeof(const struct ldp_common_header);
620 tlen = pdu_len - (sizeof(const struct ldp_common_header)-4); /* Type & Length fields not included */
621
622 while(tlen>0) {
623 /* did we capture enough for fully decoding the msg header ? */
624 ND_TCHECK2(*tptr, sizeof(struct ldp_msg_header));
625
626 ldp_msg_header = (const struct ldp_msg_header *)tptr;
627 msg_len=EXTRACT_16BITS(ldp_msg_header->length);
628 msg_type=LDP_MASK_MSG_TYPE(EXTRACT_16BITS(ldp_msg_header->type));
629
630 if (msg_len < sizeof(struct ldp_msg_header)-4) {
631 /* length too short */
632 /* FIXME vendor private / experimental check */
633 ND_PRINT((ndo, "\n\t %s Message (0x%04x), length: %u (too short, < %u)",
634 tok2str(ldp_msg_values,
635 "Unknown",
636 msg_type),
637 msg_type,
638 msg_len,
639 (u_int)(sizeof(struct ldp_msg_header)-4)));
640 return 0;
641 }
642
643 /* FIXME vendor private / experimental check */
644 ND_PRINT((ndo, "\n\t %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
645 tok2str(ldp_msg_values,
646 "Unknown",
647 msg_type),
648 msg_type,
649 msg_len,
650 EXTRACT_32BITS(&ldp_msg_header->id),
651 LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_msg_header->type)) ? "continue processing" : "ignore"));
652
653 msg_tptr=tptr+sizeof(struct ldp_msg_header);
654 msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
655
656 /* did we capture enough for fully decoding the message ? */
657 ND_TCHECK2(*tptr, msg_len);
658 hexdump=FALSE;
659
660 switch(msg_type) {
661
662 case LDP_MSG_NOTIF:
663 case LDP_MSG_HELLO:
664 case LDP_MSG_INIT:
665 case LDP_MSG_KEEPALIVE:
666 case LDP_MSG_ADDRESS:
667 case LDP_MSG_LABEL_MAPPING:
668 case LDP_MSG_ADDRESS_WITHDRAW:
669 case LDP_MSG_LABEL_WITHDRAW:
670 while(msg_tlen >= 4) {
671 processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
672 if (processed == 0)
673 break;
674 msg_tlen-=processed;
675 msg_tptr+=processed;
676 }
677 break;
678
679 /*
680 * FIXME those are the defined messages that lack a decoder
681 * you are welcome to contribute code ;-)
682 */
683
684 case LDP_MSG_LABEL_REQUEST:
685 case LDP_MSG_LABEL_RELEASE:
686 case LDP_MSG_LABEL_ABORT_REQUEST:
687
688 default:
689 if (ndo->ndo_vflag <= 1)
690 print_unknown_data(ndo, msg_tptr, "\n\t ", msg_tlen);
691 break;
692 }
693 /* do we want to see an additionally hexdump ? */
694 if (ndo->ndo_vflag > 1 || hexdump==TRUE)
695 print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t ",
696 msg_len);
697
698 tptr += msg_len+4;
699 tlen -= msg_len+4;
700 }
701 return pdu_len+4;
702 trunc:
703 ND_PRINT((ndo, "%s", tstr));
704 return 0;
705 }
706
707 /*
708 * Local Variables:
709 * c-style: whitesmith
710 * c-basic-offset: 8
711 * End:
712 */
[mirror] the TCPdump network dissector