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 1.10 2019/10/01 16:06:16 christos Exp $");
20 #endif
21
22 /* \summary: Label Distribution Protocol (LDP) printer */
23
24 #ifdef HAVE_CONFIG_H
25 #include "config.h"
26 #endif
27
28 #include <netdissect-stdinc.h>
29
30 #include "netdissect.h"
31 #include "extract.h"
32 #include "addrtoname.h"
33
34 #include "l2vpn.h"
35 #include "af.h"
36
37 static const char tstr[] = " [|LDP]";
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 uint8_t version[2];
56 uint8_t pdu_length[2];
57 uint8_t lsr_id[4];
58 uint8_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 uint8_t type[2];
89 uint8_t length[2];
90 uint8_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 Withdraw" },
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_ADDRESS_LIST_AFNUM_LEN 2
134 #define LDP_TLV_HOP_COUNT 0x0103
135 #define LDP_TLV_PATH_VECTOR 0x0104
136 #define LDP_TLV_GENERIC_LABEL 0x0200
137 #define LDP_TLV_ATM_LABEL 0x0201
138 #define LDP_TLV_FR_LABEL 0x0202
139 #define LDP_TLV_STATUS 0x0300
140 #define LDP_TLV_EXTD_STATUS 0x0301
141 #define LDP_TLV_RETURNED_PDU 0x0302
142 #define LDP_TLV_RETURNED_MSG 0x0303
143 #define LDP_TLV_COMMON_HELLO 0x0400
144 #define LDP_TLV_IPV4_TRANSPORT_ADDR 0x0401
145 #define LDP_TLV_CONFIG_SEQ_NUMBER 0x0402
146 #define LDP_TLV_IPV6_TRANSPORT_ADDR 0x0403
147 #define LDP_TLV_COMMON_SESSION 0x0500
148 #define LDP_TLV_ATM_SESSION_PARM 0x0501
149 #define LDP_TLV_FR_SESSION_PARM 0x0502
150 #define LDP_TLV_FT_SESSION 0x0503
151 #define LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
152 #define LDP_TLV_MTU 0x0601 /* rfc 3988 */
153
154 static const struct tok ldp_tlv_values[] = {
155 { LDP_TLV_FEC, "FEC" },
156 { LDP_TLV_ADDRESS_LIST, "Address List" },
157 { LDP_TLV_HOP_COUNT, "Hop Count" },
158 { LDP_TLV_PATH_VECTOR, "Path Vector" },
159 { LDP_TLV_GENERIC_LABEL, "Generic Label" },
160 { LDP_TLV_ATM_LABEL, "ATM Label" },
161 { LDP_TLV_FR_LABEL, "Frame-Relay Label" },
162 { LDP_TLV_STATUS, "Status" },
163 { LDP_TLV_EXTD_STATUS, "Extended Status" },
164 { LDP_TLV_RETURNED_PDU, "Returned PDU" },
165 { LDP_TLV_RETURNED_MSG, "Returned Message" },
166 { LDP_TLV_COMMON_HELLO, "Common Hello Parameters" },
167 { LDP_TLV_IPV4_TRANSPORT_ADDR, "IPv4 Transport Address" },
168 { LDP_TLV_CONFIG_SEQ_NUMBER, "Configuration Sequence Number" },
169 { LDP_TLV_IPV6_TRANSPORT_ADDR, "IPv6 Transport Address" },
170 { LDP_TLV_COMMON_SESSION, "Common Session Parameters" },
171 { LDP_TLV_ATM_SESSION_PARM, "ATM Session Parameters" },
172 { LDP_TLV_FR_SESSION_PARM, "Frame-Relay Session Parameters" },
173 { LDP_TLV_FT_SESSION, "Fault-Tolerant Session Parameters" },
174 { LDP_TLV_LABEL_REQUEST_MSG_ID, "Label Request Message ID" },
175 { LDP_TLV_MTU, "MTU" },
176 { 0, NULL}
177 };
178
179 #define LDP_FEC_WILDCARD 0x01
180 #define LDP_FEC_PREFIX 0x02
181 #define LDP_FEC_HOSTADDRESS 0x03
182 /* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
183 #define LDP_FEC_MARTINI_VC 0x80
184
185 static const struct tok ldp_fec_values[] = {
186 { LDP_FEC_WILDCARD, "Wildcard" },
187 { LDP_FEC_PREFIX, "Prefix" },
188 { LDP_FEC_HOSTADDRESS, "Host address" },
189 { LDP_FEC_MARTINI_VC, "Martini VC" },
190 { 0, NULL}
191 };
192
193 #define LDP_FEC_MARTINI_IFPARM_MTU 0x01
194 #define LDP_FEC_MARTINI_IFPARM_DESC 0x03
195 #define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
196
197 static const struct tok ldp_fec_martini_ifparm_values[] = {
198 { LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
199 { LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
200 { LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
201 { 0, NULL}
202 };
203
204 /* draft-ietf-pwe3-vccv-04.txt */
205 static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
206 { 0x01, "PWE3 control word" },
207 { 0x02, "MPLS Router Alert Label" },
208 { 0x04, "MPLS inner label TTL = 1" },
209 { 0, NULL}
210 };
211
212 /* draft-ietf-pwe3-vccv-04.txt */
213 static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
214 { 0x01, "ICMP Ping" },
215 { 0x02, "LSP Ping" },
216 { 0x04, "BFD" },
217 { 0, NULL}
218 };
219
220 static u_int ldp_pdu_print(netdissect_options *, register const u_char *);
221
222 /*
223 * ldp tlv header
224 *
225 * 0 1 2 3
226 * 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
227 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
228 * |U|F| Type | Length |
229 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
230 * | |
231 * | Value |
232 * ~ ~
233 * | |
234 * | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
235 * | |
236 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
237 */
238
239 #define TLV_TCHECK(minlen) \
240 ND_TCHECK2(*tptr, minlen); if (tlv_tlen < minlen) goto badtlv;
241
242 static int
ldp_tlv_print(netdissect_options * ndo,register const u_char * tptr,u_short msg_tlen)243 ldp_tlv_print(netdissect_options *ndo,
244 register const u_char *tptr,
245 u_short msg_tlen)
246 {
247 struct ldp_tlv_header {
248 uint8_t type[2];
249 uint8_t length[2];
250 };
251
252 const struct ldp_tlv_header *ldp_tlv_header;
253 u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
254 u_char fec_type;
255 u_int ui,vc_info_len, vc_info_tlv_type, vc_info_tlv_len,idx;
256 char buf[100];
257 int i;
258
259 ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
260 ND_TCHECK(*ldp_tlv_header);
261 tlv_len=EXTRACT_16BITS(ldp_tlv_header->length);
262 if (tlv_len + 4 > msg_tlen) {
263 ND_PRINT((ndo, "\n\t\t TLV contents go past end of message"));
264 return 0;
265 }
266 tlv_tlen=tlv_len;
267 tlv_type=LDP_MASK_TLV_TYPE(EXTRACT_16BITS(ldp_tlv_header->type));
268
269 /* FIXME vendor private / experimental check */
270 ND_PRINT((ndo, "\n\t %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
271 tok2str(ldp_tlv_values,
272 "Unknown",
273 tlv_type),
274 tlv_type,
275 tlv_len,
276 LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "continue processing" : "ignore",
277 LDP_MASK_F_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "do" : "don't"));
278
279 tptr+=sizeof(struct ldp_tlv_header);
280
281 switch(tlv_type) {
282
283 case LDP_TLV_COMMON_HELLO:
284 TLV_TCHECK(4);
285 ND_PRINT((ndo, "\n\t Hold Time: %us, Flags: [%s Hello%s]",
286 EXTRACT_16BITS(tptr),
287 (EXTRACT_16BITS(tptr+2)&0x8000) ? "Targeted" : "Link",
288 (EXTRACT_16BITS(tptr+2)&0x4000) ? ", Request for targeted Hellos" : ""));
289 break;
290
291 case LDP_TLV_IPV4_TRANSPORT_ADDR:
292 TLV_TCHECK(4);
293 ND_PRINT((ndo, "\n\t IPv4 Transport Address: %s", ipaddr_string(ndo, tptr)));
294 break;
295 case LDP_TLV_IPV6_TRANSPORT_ADDR:
296 TLV_TCHECK(16);
297 ND_PRINT((ndo, "\n\t IPv6 Transport Address: %s", ip6addr_string(ndo, tptr)));
298 break;
299 case LDP_TLV_CONFIG_SEQ_NUMBER:
300 TLV_TCHECK(4);
301 ND_PRINT((ndo, "\n\t Sequence Number: %u", EXTRACT_32BITS(tptr)));
302 break;
303
304 case LDP_TLV_ADDRESS_LIST:
305 TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
306 af = EXTRACT_16BITS(tptr);
307 tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
308 tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
309 ND_PRINT((ndo, "\n\t Address Family: %s, addresses",
310 tok2str(af_values, "Unknown (%u)", af)));
311 switch (af) {
312 case AFNUM_INET:
313 while(tlv_tlen >= sizeof(struct in_addr)) {
314 ND_TCHECK2(*tptr, sizeof(struct in_addr));
315 ND_PRINT((ndo, " %s", ipaddr_string(ndo, tptr)));
316 tlv_tlen-=sizeof(struct in_addr);
317 tptr+=sizeof(struct in_addr);
318 }
319 break;
320 case AFNUM_INET6:
321 while(tlv_tlen >= sizeof(struct in6_addr)) {
322 ND_TCHECK2(*tptr, sizeof(struct in6_addr));
323 ND_PRINT((ndo, " %s", ip6addr_string(ndo, tptr)));
324 tlv_tlen-=sizeof(struct in6_addr);
325 tptr+=sizeof(struct in6_addr);
326 }
327 break;
328 default:
329 /* unknown AF */
330 break;
331 }
332 break;
333
334 case LDP_TLV_COMMON_SESSION:
335 TLV_TCHECK(8);
336 ND_PRINT((ndo, "\n\t Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
337 EXTRACT_16BITS(tptr), EXTRACT_16BITS(tptr+2),
338 (EXTRACT_16BITS(tptr+6)&0x8000) ? "On Demand" : "Unsolicited",
339 (EXTRACT_16BITS(tptr+6)&0x4000) ? "Enabled" : "Disabled"
340 ));
341 break;
342
343 case LDP_TLV_FEC:
344 TLV_TCHECK(1);
345 fec_type = *tptr;
346 ND_PRINT((ndo, "\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 = EXTRACT_16BITS(tptr);
359 tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
360 tlv_tlen-=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
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((ndo, ": IPv4 prefix (goes past end of TLV)"));
367 else if (i == -1)
368 ND_PRINT((ndo, ": IPv4 prefix (invalid length)"));
369 else
370 ND_PRINT((ndo, ": IPv4 prefix %s", buf));
371 }
372 else if (af == AFNUM_INET6) {
373 i=decode_prefix6(ndo, tptr, tlv_tlen, buf, sizeof(buf));
374 if (i == -2)
375 goto trunc;
376 if (i == -3)
377 ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
378 else if (i == -1)
379 ND_PRINT((ndo, ": IPv6 prefix (invalid length)"));
380 else
381 ND_PRINT((ndo, ": IPv6 prefix %s", buf));
382 }
383 else
384 ND_PRINT((ndo, ": Address family %u prefix", af));
385 break;
386 case LDP_FEC_HOSTADDRESS:
387 break;
388 case LDP_FEC_MARTINI_VC:
389 /*
390 * We assume the type was supposed to be one of the MPLS
391 * Pseudowire Types.
392 */
393 TLV_TCHECK(7);
394 vc_info_len = *(tptr+2);
395
396 /*
397 * According to RFC 4908, the VC info Length field can be zero,
398 * in which case not only are there no interface parameters,
399 * there's no VC ID.
400 */
401 if (vc_info_len == 0) {
402 ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-info-length: %u",
403 tok2str(mpls_pw_types_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
404 EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
405 EXTRACT_32BITS(tptr+3),
406 vc_info_len));
407 break;
408 }
409
410 /* Make sure we have the VC ID as well */
411 TLV_TCHECK(11);
412 ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
413 tok2str(mpls_pw_types_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
414 EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
415 EXTRACT_32BITS(tptr+3),
416 EXTRACT_32BITS(tptr+7),
417 vc_info_len));
418 if (vc_info_len < 4) {
419 /* minimum 4, for the VC ID */
420 ND_PRINT((ndo, " (invalid, < 4"));
421 return(tlv_len+4); /* Type & Length fields not included */
422 }
423 vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
424
425 /* Skip past the fixed information and the VC ID */
426 tptr+=11;
427 tlv_tlen-=11;
428 TLV_TCHECK(vc_info_len);
429
430 while (vc_info_len > 2) {
431 vc_info_tlv_type = *tptr;
432 vc_info_tlv_len = *(tptr+1);
433 if (vc_info_tlv_len < 2)
434 break;
435 if (vc_info_len < vc_info_tlv_len)
436 break;
437
438 ND_PRINT((ndo, "\n\t\tInterface Parameter: %s (0x%02x), len %u",
439 tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
440 vc_info_tlv_type,
441 vc_info_tlv_len));
442
443 switch(vc_info_tlv_type) {
444 case LDP_FEC_MARTINI_IFPARM_MTU:
445 ND_TCHECK_16BITS(tptr + 2);
446 ND_PRINT((ndo, ": %u", EXTRACT_16BITS(tptr+2)));
447 break;
448
449 case LDP_FEC_MARTINI_IFPARM_DESC:
450 ND_PRINT((ndo, ": "));
451 for (idx = 2; idx < vc_info_tlv_len; idx++) {
452 ND_TCHECK_8BITS(tptr + idx);
453 safeputchar(ndo, *(tptr + idx));
454 }
455 break;
456
457 case LDP_FEC_MARTINI_IFPARM_VCCV:
458 ND_TCHECK_8BITS(tptr + 2);
459 ND_PRINT((ndo, "\n\t\t Control Channels (0x%02x) = [%s]",
460 *(tptr+2),
461 bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", *(tptr+2))));
462 ND_TCHECK_8BITS(tptr + 3);
463 ND_PRINT((ndo, "\n\t\t CV Types (0x%02x) = [%s]",
464 *(tptr+3),
465 bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", *(tptr+3))));
466 break;
467
468 default:
469 print_unknown_data(ndo, tptr+2, "\n\t\t ", vc_info_tlv_len-2);
470 break;
471 }
472
473 vc_info_len -= vc_info_tlv_len;
474 tptr += vc_info_tlv_len;
475 }
476 break;
477 }
478
479 break;
480
481 case LDP_TLV_GENERIC_LABEL:
482 TLV_TCHECK(4);
483 ND_PRINT((ndo, "\n\t Label: %u", EXTRACT_32BITS(tptr) & 0xfffff));
484 break;
485
486 case LDP_TLV_STATUS:
487 TLV_TCHECK(8);
488 ui = EXTRACT_32BITS(tptr);
489 tptr+=4;
490 ND_PRINT((ndo, "\n\t Status: 0x%02x, Flags: [%s and %s forward]",
491 ui&0x3fffffff,
492 ui&0x80000000 ? "Fatal error" : "Advisory Notification",
493 ui&0x40000000 ? "do" : "don't"));
494 ui = EXTRACT_32BITS(tptr);
495 tptr+=4;
496 if (ui)
497 ND_PRINT((ndo, ", causing Message ID: 0x%08x", ui));
498 break;
499
500 case LDP_TLV_FT_SESSION:
501 TLV_TCHECK(12);
502 ft_flags = EXTRACT_16BITS(tptr);
503 ND_PRINT((ndo, "\n\t Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
504 ft_flags&0x8000 ? "" : "No ",
505 ft_flags&0x8 ? "" : "Don't ",
506 ft_flags&0x4 ? "" : "No ",
507 ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
508 ft_flags&0x1 ? "" : "Don't "));
509 /* 16 bits (FT Flags) + 16 bits (Reserved) */
510 tptr+=4;
511 ui = EXTRACT_32BITS(tptr);
512 if (ui)
513 ND_PRINT((ndo, ", Reconnect Timeout: %ums", ui));
514 tptr+=4;
515 ui = EXTRACT_32BITS(tptr);
516 if (ui)
517 ND_PRINT((ndo, ", Recovery Time: %ums", ui));
518 break;
519
520 case LDP_TLV_MTU:
521 TLV_TCHECK(2);
522 ND_PRINT((ndo, "\n\t MTU: %u", EXTRACT_16BITS(tptr)));
523 break;
524
525
526 /*
527 * FIXME those are the defined TLVs that lack a decoder
528 * you are welcome to contribute code ;-)
529 */
530
531 case LDP_TLV_HOP_COUNT:
532 case LDP_TLV_PATH_VECTOR:
533 case LDP_TLV_ATM_LABEL:
534 case LDP_TLV_FR_LABEL:
535 case LDP_TLV_EXTD_STATUS:
536 case LDP_TLV_RETURNED_PDU:
537 case LDP_TLV_RETURNED_MSG:
538 case LDP_TLV_ATM_SESSION_PARM:
539 case LDP_TLV_FR_SESSION_PARM:
540 case LDP_TLV_LABEL_REQUEST_MSG_ID:
541
542 default:
543 if (ndo->ndo_vflag <= 1)
544 print_unknown_data(ndo, tptr, "\n\t ", tlv_tlen);
545 break;
546 }
547 return(tlv_len+4); /* Type & Length fields not included */
548
549 trunc:
550 ND_PRINT((ndo, "%s", tstr));
551 return 0;
552
553 badtlv:
554 ND_PRINT((ndo, "\n\t\t TLV contents go past end of TLV"));
555 return(tlv_len+4); /* Type & Length fields not included */
556 }
557
558 void
ldp_print(netdissect_options * ndo,register const u_char * pptr,register u_int len)559 ldp_print(netdissect_options *ndo,
560 register const u_char *pptr, register u_int len)
561 {
562 u_int processed;
563 while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
564 processed = ldp_pdu_print(ndo, pptr);
565 if (processed == 0)
566 return;
567 if (len < processed) {
568 ND_PRINT((ndo, " [remaining length %u < %u]", len, processed));
569 ND_PRINT((ndo, "%s", istr));
570 break;
571
572 }
573 len -= processed;
574 pptr += processed;
575 }
576 }
577
578 static u_int
ldp_pdu_print(netdissect_options * ndo,register const u_char * pptr)579 ldp_pdu_print(netdissect_options *ndo,
580 register const u_char *pptr)
581 {
582 const struct ldp_common_header *ldp_com_header;
583 const struct ldp_msg_header *ldp_msg_header;
584 const u_char *tptr,*msg_tptr;
585 u_short tlen;
586 u_short pdu_len,msg_len,msg_type,msg_tlen;
587 int hexdump,processed;
588
589 ldp_com_header = (const struct ldp_common_header *)pptr;
590 ND_TCHECK(*ldp_com_header);
591
592 /*
593 * Sanity checking of the header.
594 */
595 if (EXTRACT_16BITS(&ldp_com_header->version) != LDP_VERSION) {
596 ND_PRINT((ndo, "%sLDP version %u packet not supported",
597 (ndo->ndo_vflag < 1) ? "" : "\n\t",
598 EXTRACT_16BITS(&ldp_com_header->version)));
599 return 0;
600 }
601
602 pdu_len = EXTRACT_16BITS(&ldp_com_header->pdu_length);
603 if (pdu_len < sizeof(const struct ldp_common_header)-4) {
604 /* length too short */
605 ND_PRINT((ndo, "%sLDP, pdu-length: %u (too short, < %u)",
606 (ndo->ndo_vflag < 1) ? "" : "\n\t",
607 pdu_len,
608 (u_int)(sizeof(const struct ldp_common_header)-4)));
609 return 0;
610 }
611
612 /* print the LSR-ID, label-space & length */
613 ND_PRINT((ndo, "%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
614 (ndo->ndo_vflag < 1) ? "" : "\n\t",
615 ipaddr_string(ndo, &ldp_com_header->lsr_id),
616 EXTRACT_16BITS(&ldp_com_header->label_space),
617 pdu_len));
618
619 /* bail out if non-verbose */
620 if (ndo->ndo_vflag < 1)
621 return 0;
622
623 /* ok they seem to want to know everything - lets fully decode it */
624 tptr = pptr + sizeof(const struct ldp_common_header);
625 tlen = pdu_len - (sizeof(const struct ldp_common_header)-4); /* Type & Length fields not included */
626
627 while(tlen>0) {
628 /* did we capture enough for fully decoding the msg header ? */
629 ND_TCHECK2(*tptr, sizeof(struct ldp_msg_header));
630
631 ldp_msg_header = (const struct ldp_msg_header *)tptr;
632 msg_len=EXTRACT_16BITS(ldp_msg_header->length);
633 msg_type=LDP_MASK_MSG_TYPE(EXTRACT_16BITS(ldp_msg_header->type));
634
635 if (msg_len < sizeof(struct ldp_msg_header)-4) {
636 /* length too short */
637 /* FIXME vendor private / experimental check */
638 ND_PRINT((ndo, "\n\t %s Message (0x%04x), length: %u (too short, < %u)",
639 tok2str(ldp_msg_values,
640 "Unknown",
641 msg_type),
642 msg_type,
643 msg_len,
644 (u_int)(sizeof(struct ldp_msg_header)-4)));
645 return 0;
646 }
647
648 /* FIXME vendor private / experimental check */
649 ND_PRINT((ndo, "\n\t %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
650 tok2str(ldp_msg_values,
651 "Unknown",
652 msg_type),
653 msg_type,
654 msg_len,
655 EXTRACT_32BITS(&ldp_msg_header->id),
656 LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_msg_header->type)) ? "continue processing" : "ignore"));
657
658 msg_tptr=tptr+sizeof(struct ldp_msg_header);
659 msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
660
661 /* did we capture enough for fully decoding the message ? */
662 ND_TCHECK2(*tptr, msg_len);
663 hexdump=FALSE;
664
665 switch(msg_type) {
666
667 case LDP_MSG_NOTIF:
668 case LDP_MSG_HELLO:
669 case LDP_MSG_INIT:
670 case LDP_MSG_KEEPALIVE:
671 case LDP_MSG_ADDRESS:
672 case LDP_MSG_LABEL_MAPPING:
673 case LDP_MSG_ADDRESS_WITHDRAW:
674 case LDP_MSG_LABEL_WITHDRAW:
675 while(msg_tlen >= 4) {
676 processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
677 if (processed == 0)
678 break;
679 msg_tlen-=processed;
680 msg_tptr+=processed;
681 }
682 break;
683
684 /*
685 * FIXME those are the defined messages that lack a decoder
686 * you are welcome to contribute code ;-)
687 */
688
689 case LDP_MSG_LABEL_REQUEST:
690 case LDP_MSG_LABEL_RELEASE:
691 case LDP_MSG_LABEL_ABORT_REQUEST:
692
693 default:
694 if (ndo->ndo_vflag <= 1)
695 print_unknown_data(ndo, msg_tptr, "\n\t ", msg_tlen);
696 break;
697 }
698 /* do we want to see an additionally hexdump ? */
699 if (ndo->ndo_vflag > 1 || hexdump==TRUE)
700 print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t ",
701 msg_len);
702
703 tptr += msg_len+4;
704 tlen -= msg_len+4;
705 }
706 return pdu_len+4;
707 trunc:
708 ND_PRINT((ndo, "%s", tstr));
709 return 0;
710 }
711
712 /*
713 * Local Variables:
714 * c-style: whitesmith
715 * c-basic-offset: 8
716 * End:
717 */
718