1 /*
2 * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 *
21 * $FreeBSD$
22 */
23
24 #define NETDISSECT_REWORKED
25 #ifdef HAVE_CONFIG_H
26 #include "config.h"
27 #endif
28
29 #include <tcpdump-stdinc.h>
30
31 #include <stdio.h>
32 #include <string.h>
33
34 #include "interface.h"
35 #include "addrtoname.h"
36 #include "ethertype.h"
37 #include "llc.h"
38 #include "nlpid.h"
39 #include "extract.h"
40 #include "oui.h"
41
42 static void frf15_print(netdissect_options *ndo, const u_char *, u_int);
43
44 /*
45 * the frame relay header has a variable length
46 *
47 * the EA bit determines if there is another byte
48 * in the header
49 *
50 * minimum header length is 2 bytes
51 * maximum header length is 4 bytes
52 *
53 * 7 6 5 4 3 2 1 0
54 * +----+----+----+----+----+----+----+----+
55 * | DLCI (6 bits) | CR | EA |
56 * +----+----+----+----+----+----+----+----+
57 * | DLCI (4 bits) |FECN|BECN| DE | EA |
58 * +----+----+----+----+----+----+----+----+
59 * | DLCI (7 bits) | EA |
60 * +----+----+----+----+----+----+----+----+
61 * | DLCI (6 bits) |SDLC| EA |
62 * +----+----+----+----+----+----+----+----+
63 */
64
65 #define FR_EA_BIT 0x01
66
67 #define FR_CR_BIT 0x02000000
68 #define FR_DE_BIT 0x00020000
69 #define FR_BECN_BIT 0x00040000
70 #define FR_FECN_BIT 0x00080000
71 #define FR_SDLC_BIT 0x00000002
72
73
74 static const struct tok fr_header_flag_values[] = {
75 { FR_CR_BIT, "C!" },
76 { FR_DE_BIT, "DE" },
77 { FR_BECN_BIT, "BECN" },
78 { FR_FECN_BIT, "FECN" },
79 { FR_SDLC_BIT, "sdlcore" },
80 { 0, NULL }
81 };
82
83 /* FRF.15 / FRF.16 */
84 #define MFR_B_BIT 0x80
85 #define MFR_E_BIT 0x40
86 #define MFR_C_BIT 0x20
87 #define MFR_BEC_MASK (MFR_B_BIT | MFR_E_BIT | MFR_C_BIT)
88 #define MFR_CTRL_FRAME (MFR_B_BIT | MFR_E_BIT | MFR_C_BIT)
89 #define MFR_FRAG_FRAME (MFR_B_BIT | MFR_E_BIT )
90
91 static const struct tok frf_flag_values[] = {
92 { MFR_B_BIT, "Begin" },
93 { MFR_E_BIT, "End" },
94 { MFR_C_BIT, "Control" },
95 { 0, NULL }
96 };
97
98 /* Finds out Q.922 address length, DLCI and flags. Returns 1 on success,
99 * 0 on invalid address, -1 on truncated packet
100 * save the flags dep. on address length
101 */
parse_q922_addr(netdissect_options * ndo,const u_char * p,u_int * dlci,u_int * addr_len,uint8_t * flags,u_int length)102 static int parse_q922_addr(netdissect_options *ndo,
103 const u_char *p, u_int *dlci,
104 u_int *addr_len, uint8_t *flags, u_int length)
105 {
106 if (!ND_TTEST(p[0]) || length < 1)
107 return -1;
108 if ((p[0] & FR_EA_BIT))
109 return 0;
110
111 if (!ND_TTEST(p[1]) || length < 2)
112 return -1;
113 *addr_len = 2;
114 *dlci = ((p[0] & 0xFC) << 2) | ((p[1] & 0xF0) >> 4);
115
116 flags[0] = p[0] & 0x02; /* populate the first flag fields */
117 flags[1] = p[1] & 0x0c;
118 flags[2] = 0; /* clear the rest of the flags */
119 flags[3] = 0;
120
121 if (p[1] & FR_EA_BIT)
122 return 1; /* 2-byte Q.922 address */
123
124 p += 2;
125 length -= 2;
126 if (!ND_TTEST(p[0]) || length < 1)
127 return -1;
128 (*addr_len)++; /* 3- or 4-byte Q.922 address */
129 if ((p[0] & FR_EA_BIT) == 0) {
130 *dlci = (*dlci << 7) | (p[0] >> 1);
131 (*addr_len)++; /* 4-byte Q.922 address */
132 p++;
133 length--;
134 }
135
136 if (!ND_TTEST(p[0]) || length < 1)
137 return -1;
138 if ((p[0] & FR_EA_BIT) == 0)
139 return 0; /* more than 4 bytes of Q.922 address? */
140
141 flags[3] = p[0] & 0x02;
142
143 *dlci = (*dlci << 6) | (p[0] >> 2);
144
145 return 1;
146 }
147
148 char *
q922_string(netdissect_options * ndo,const u_char * p,u_int length)149 q922_string(netdissect_options *ndo, const u_char *p, u_int length)
150 {
151
152 static u_int dlci, addr_len;
153 static uint8_t flags[4];
154 static char buffer[sizeof("DLCI xxxxxxxxxx")];
155 memset(buffer, 0, sizeof(buffer));
156
157 if (parse_q922_addr(ndo, p, &dlci, &addr_len, flags, length) == 1){
158 snprintf(buffer, sizeof(buffer), "DLCI %u", dlci);
159 }
160
161 return buffer;
162 }
163
164
165 /* Frame Relay packet structure, with flags and CRC removed
166
167 +---------------------------+
168 | Q.922 Address* |
169 +-- --+
170 | |
171 +---------------------------+
172 | Control (UI = 0x03) |
173 +---------------------------+
174 | Optional Pad (0x00) |
175 +---------------------------+
176 | NLPID |
177 +---------------------------+
178 | . |
179 | . |
180 | . |
181 | Data |
182 | . |
183 | . |
184 +---------------------------+
185
186 * Q.922 addresses, as presently defined, are two octets and
187 contain a 10-bit DLCI. In some networks Q.922 addresses
188 may optionally be increased to three or four octets.
189 */
190
191 static void
fr_hdr_print(netdissect_options * ndo,int length,u_int addr_len,u_int dlci,uint8_t * flags,uint16_t nlpid)192 fr_hdr_print(netdissect_options *ndo,
193 int length, u_int addr_len, u_int dlci, uint8_t *flags, uint16_t nlpid)
194 {
195 if (ndo->ndo_qflag) {
196 ND_PRINT((ndo, "Q.922, DLCI %u, length %u: ",
197 dlci,
198 length));
199 } else {
200 if (nlpid <= 0xff) /* if its smaller than 256 then its a NLPID */
201 ND_PRINT((ndo, "Q.922, hdr-len %u, DLCI %u, Flags [%s], NLPID %s (0x%02x), length %u: ",
202 addr_len,
203 dlci,
204 bittok2str(fr_header_flag_values, "none", EXTRACT_32BITS(flags)),
205 tok2str(nlpid_values,"unknown", nlpid),
206 nlpid,
207 length));
208 else /* must be an ethertype */
209 ND_PRINT((ndo, "Q.922, hdr-len %u, DLCI %u, Flags [%s], cisco-ethertype %s (0x%04x), length %u: ",
210 addr_len,
211 dlci,
212 bittok2str(fr_header_flag_values, "none", EXTRACT_32BITS(flags)),
213 tok2str(ethertype_values, "unknown", nlpid),
214 nlpid,
215 length));
216 }
217 }
218
219 u_int
fr_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,register const u_char * p)220 fr_if_print(netdissect_options *ndo,
221 const struct pcap_pkthdr *h, register const u_char *p)
222 {
223 register u_int length = h->len;
224 register u_int caplen = h->caplen;
225
226 ND_TCHECK2(*p, 4); /* minimum frame header length */
227
228 if ((length = fr_print(ndo, p, length)) == 0)
229 return (0);
230 else
231 return length;
232 trunc:
233 ND_PRINT((ndo, "[|fr]"));
234 return caplen;
235 }
236
237 u_int
fr_print(netdissect_options * ndo,register const u_char * p,u_int length)238 fr_print(netdissect_options *ndo,
239 register const u_char *p, u_int length)
240 {
241 int ret;
242 uint16_t extracted_ethertype;
243 u_int dlci;
244 u_int addr_len;
245 uint16_t nlpid;
246 u_int hdr_len;
247 uint8_t flags[4];
248
249 ret = parse_q922_addr(ndo, p, &dlci, &addr_len, flags, length);
250 if (ret == -1)
251 goto trunc;
252 if (ret == 0) {
253 ND_PRINT((ndo, "Q.922, invalid address"));
254 return 0;
255 }
256
257 ND_TCHECK(p[addr_len]);
258 if (length < addr_len + 1)
259 goto trunc;
260
261 if (p[addr_len] != LLC_UI && dlci != 0) {
262 /*
263 * Let's figure out if we have Cisco-style encapsulation,
264 * with an Ethernet type (Cisco HDLC type?) following the
265 * address.
266 */
267 if (!ND_TTEST2(p[addr_len], 2) || length < addr_len + 2) {
268 /* no Ethertype */
269 ND_PRINT((ndo, "UI %02x! ", p[addr_len]));
270 } else {
271 extracted_ethertype = EXTRACT_16BITS(p+addr_len);
272
273 if (ndo->ndo_eflag)
274 fr_hdr_print(ndo, length, addr_len, dlci,
275 flags, extracted_ethertype);
276
277 if (ethertype_print(ndo, extracted_ethertype,
278 p+addr_len+ETHERTYPE_LEN,
279 length-addr_len-ETHERTYPE_LEN,
280 length-addr_len-ETHERTYPE_LEN) == 0)
281 /* ether_type not known, probably it wasn't one */
282 ND_PRINT((ndo, "UI %02x! ", p[addr_len]));
283 else
284 return addr_len + 2;
285 }
286 }
287
288 ND_TCHECK(p[addr_len+1]);
289 if (length < addr_len + 2)
290 goto trunc;
291
292 if (p[addr_len + 1] == 0) {
293 /*
294 * Assume a pad byte after the control (UI) byte.
295 * A pad byte should only be used with 3-byte Q.922.
296 */
297 if (addr_len != 3)
298 ND_PRINT((ndo, "Pad! "));
299 hdr_len = addr_len + 1 /* UI */ + 1 /* pad */ + 1 /* NLPID */;
300 } else {
301 /*
302 * Not a pad byte.
303 * A pad byte should be used with 3-byte Q.922.
304 */
305 if (addr_len == 3)
306 ND_PRINT((ndo, "No pad! "));
307 hdr_len = addr_len + 1 /* UI */ + 1 /* NLPID */;
308 }
309
310 ND_TCHECK(p[hdr_len - 1]);
311 if (length < hdr_len)
312 goto trunc;
313 nlpid = p[hdr_len - 1];
314
315 if (ndo->ndo_eflag)
316 fr_hdr_print(ndo, length, addr_len, dlci, flags, nlpid);
317 p += hdr_len;
318 length -= hdr_len;
319
320 switch (nlpid) {
321 case NLPID_IP:
322 ip_print(ndo, p, length);
323 break;
324
325 case NLPID_IP6:
326 ip6_print(ndo, p, length);
327 break;
328
329 case NLPID_CLNP:
330 case NLPID_ESIS:
331 case NLPID_ISIS:
332 isoclns_print(ndo, p - 1, length + 1, length + 1); /* OSI printers need the NLPID field */
333 break;
334
335 case NLPID_SNAP:
336 if (snap_print(ndo, p, length, length, 0) == 0) {
337 /* ether_type not known, print raw packet */
338 if (!ndo->ndo_eflag)
339 fr_hdr_print(ndo, length + hdr_len, hdr_len,
340 dlci, flags, nlpid);
341 if (!ndo->ndo_suppress_default_print)
342 ND_DEFAULTPRINT(p - hdr_len, length + hdr_len);
343 }
344 break;
345
346 case NLPID_Q933:
347 q933_print(ndo, p, length);
348 break;
349
350 case NLPID_MFR:
351 frf15_print(ndo, p, length);
352 break;
353
354 case NLPID_PPP:
355 ppp_print(ndo, p, length);
356 break;
357
358 default:
359 if (!ndo->ndo_eflag)
360 fr_hdr_print(ndo, length + hdr_len, addr_len,
361 dlci, flags, nlpid);
362 if (!ndo->ndo_xflag)
363 ND_DEFAULTPRINT(p, length);
364 }
365
366 return hdr_len;
367
368 trunc:
369 ND_PRINT((ndo, "[|fr]"));
370 return 0;
371
372 }
373
374 u_int
mfr_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,register const u_char * p)375 mfr_if_print(netdissect_options *ndo,
376 const struct pcap_pkthdr *h, register const u_char *p)
377 {
378 register u_int length = h->len;
379 register u_int caplen = h->caplen;
380
381 ND_TCHECK2(*p, 2); /* minimum frame header length */
382
383 if ((length = mfr_print(ndo, p, length)) == 0)
384 return (0);
385 else
386 return length;
387 trunc:
388 ND_PRINT((ndo, "[|mfr]"));
389 return caplen;
390 }
391
392
393 #define MFR_CTRL_MSG_ADD_LINK 1
394 #define MFR_CTRL_MSG_ADD_LINK_ACK 2
395 #define MFR_CTRL_MSG_ADD_LINK_REJ 3
396 #define MFR_CTRL_MSG_HELLO 4
397 #define MFR_CTRL_MSG_HELLO_ACK 5
398 #define MFR_CTRL_MSG_REMOVE_LINK 6
399 #define MFR_CTRL_MSG_REMOVE_LINK_ACK 7
400
401 static const struct tok mfr_ctrl_msg_values[] = {
402 { MFR_CTRL_MSG_ADD_LINK, "Add Link" },
403 { MFR_CTRL_MSG_ADD_LINK_ACK, "Add Link ACK" },
404 { MFR_CTRL_MSG_ADD_LINK_REJ, "Add Link Reject" },
405 { MFR_CTRL_MSG_HELLO, "Hello" },
406 { MFR_CTRL_MSG_HELLO_ACK, "Hello ACK" },
407 { MFR_CTRL_MSG_REMOVE_LINK, "Remove Link" },
408 { MFR_CTRL_MSG_REMOVE_LINK_ACK, "Remove Link ACK" },
409 { 0, NULL }
410 };
411
412 #define MFR_CTRL_IE_BUNDLE_ID 1
413 #define MFR_CTRL_IE_LINK_ID 2
414 #define MFR_CTRL_IE_MAGIC_NUM 3
415 #define MFR_CTRL_IE_TIMESTAMP 5
416 #define MFR_CTRL_IE_VENDOR_EXT 6
417 #define MFR_CTRL_IE_CAUSE 7
418
419 static const struct tok mfr_ctrl_ie_values[] = {
420 { MFR_CTRL_IE_BUNDLE_ID, "Bundle ID"},
421 { MFR_CTRL_IE_LINK_ID, "Link ID"},
422 { MFR_CTRL_IE_MAGIC_NUM, "Magic Number"},
423 { MFR_CTRL_IE_TIMESTAMP, "Timestamp"},
424 { MFR_CTRL_IE_VENDOR_EXT, "Vendor Extension"},
425 { MFR_CTRL_IE_CAUSE, "Cause"},
426 { 0, NULL }
427 };
428
429 #define MFR_ID_STRING_MAXLEN 50
430
431 struct ie_tlv_header_t {
432 uint8_t ie_type;
433 uint8_t ie_len;
434 };
435
436 u_int
mfr_print(netdissect_options * ndo,register const u_char * p,u_int length)437 mfr_print(netdissect_options *ndo,
438 register const u_char *p, u_int length)
439 {
440 u_int tlen,idx,hdr_len = 0;
441 uint16_t sequence_num;
442 uint8_t ie_type,ie_len;
443 const uint8_t *tptr;
444
445
446 /*
447 * FRF.16 Link Integrity Control Frame
448 *
449 * 7 6 5 4 3 2 1 0
450 * +----+----+----+----+----+----+----+----+
451 * | B | E | C=1| 0 0 0 0 | EA |
452 * +----+----+----+----+----+----+----+----+
453 * | 0 0 0 0 0 0 0 0 |
454 * +----+----+----+----+----+----+----+----+
455 * | message type |
456 * +----+----+----+----+----+----+----+----+
457 */
458
459 ND_TCHECK2(*p, 4); /* minimum frame header length */
460
461 if ((p[0] & MFR_BEC_MASK) == MFR_CTRL_FRAME && p[1] == 0) {
462 ND_PRINT((ndo, "FRF.16 Control, Flags [%s], %s, length %u",
463 bittok2str(frf_flag_values,"none",(p[0] & MFR_BEC_MASK)),
464 tok2str(mfr_ctrl_msg_values,"Unknown Message (0x%02x)",p[2]),
465 length));
466 tptr = p + 3;
467 tlen = length -3;
468 hdr_len = 3;
469
470 if (!ndo->ndo_vflag)
471 return hdr_len;
472
473 while (tlen>sizeof(struct ie_tlv_header_t)) {
474 ND_TCHECK2(*tptr, sizeof(struct ie_tlv_header_t));
475 ie_type=tptr[0];
476 ie_len=tptr[1];
477
478 ND_PRINT((ndo, "\n\tIE %s (%u), length %u: ",
479 tok2str(mfr_ctrl_ie_values,"Unknown",ie_type),
480 ie_type,
481 ie_len));
482
483 /* infinite loop check */
484 if (ie_type == 0 || ie_len <= sizeof(struct ie_tlv_header_t))
485 return hdr_len;
486
487 ND_TCHECK2(*tptr, ie_len);
488 tptr+=sizeof(struct ie_tlv_header_t);
489 /* tlv len includes header */
490 ie_len-=sizeof(struct ie_tlv_header_t);
491 tlen-=sizeof(struct ie_tlv_header_t);
492
493 switch (ie_type) {
494
495 case MFR_CTRL_IE_MAGIC_NUM:
496 ND_PRINT((ndo, "0x%08x", EXTRACT_32BITS(tptr)));
497 break;
498
499 case MFR_CTRL_IE_BUNDLE_ID: /* same message format */
500 case MFR_CTRL_IE_LINK_ID:
501 for (idx = 0; idx < ie_len && idx < MFR_ID_STRING_MAXLEN; idx++) {
502 if (*(tptr+idx) != 0) /* don't print null termination */
503 safeputchar(ndo, *(tptr + idx));
504 else
505 break;
506 }
507 break;
508
509 case MFR_CTRL_IE_TIMESTAMP:
510 if (ie_len == sizeof(struct timeval)) {
511 ts_print(ndo, (const struct timeval *)tptr);
512 break;
513 }
514 /* fall through and hexdump if no unix timestamp */
515
516 /*
517 * FIXME those are the defined IEs that lack a decoder
518 * you are welcome to contribute code ;-)
519 */
520
521 case MFR_CTRL_IE_VENDOR_EXT:
522 case MFR_CTRL_IE_CAUSE:
523
524 default:
525 if (ndo->ndo_vflag <= 1)
526 print_unknown_data(ndo, tptr, "\n\t ", ie_len);
527 break;
528 }
529
530 /* do we want to see a hexdump of the IE ? */
531 if (ndo->ndo_vflag > 1 )
532 print_unknown_data(ndo, tptr, "\n\t ", ie_len);
533
534 tlen-=ie_len;
535 tptr+=ie_len;
536 }
537 return hdr_len;
538 }
539 /*
540 * FRF.16 Fragmentation Frame
541 *
542 * 7 6 5 4 3 2 1 0
543 * +----+----+----+----+----+----+----+----+
544 * | B | E | C=0|seq. (high 4 bits) | EA |
545 * +----+----+----+----+----+----+----+----+
546 * | sequence (low 8 bits) |
547 * +----+----+----+----+----+----+----+----+
548 * | DLCI (6 bits) | CR | EA |
549 * +----+----+----+----+----+----+----+----+
550 * | DLCI (4 bits) |FECN|BECN| DE | EA |
551 * +----+----+----+----+----+----+----+----+
552 */
553
554 sequence_num = (p[0]&0x1e)<<7 | p[1];
555 /* whole packet or first fragment ? */
556 if ((p[0] & MFR_BEC_MASK) == MFR_FRAG_FRAME ||
557 (p[0] & MFR_BEC_MASK) == MFR_B_BIT) {
558 ND_PRINT((ndo, "FRF.16 Frag, seq %u, Flags [%s], ",
559 sequence_num,
560 bittok2str(frf_flag_values,"none",(p[0] & MFR_BEC_MASK))));
561 hdr_len = 2;
562 fr_print(ndo, p+hdr_len,length-hdr_len);
563 return hdr_len;
564 }
565
566 /* must be a middle or the last fragment */
567 ND_PRINT((ndo, "FRF.16 Frag, seq %u, Flags [%s]",
568 sequence_num,
569 bittok2str(frf_flag_values,"none",(p[0] & MFR_BEC_MASK))));
570 print_unknown_data(ndo, p, "\n\t", length);
571
572 return hdr_len;
573
574 trunc:
575 ND_PRINT((ndo, "[|mfr]"));
576 return length;
577 }
578
579 /* an NLPID of 0xb1 indicates a 2-byte
580 * FRF.15 header
581 *
582 * 7 6 5 4 3 2 1 0
583 * +----+----+----+----+----+----+----+----+
584 * ~ Q.922 header ~
585 * +----+----+----+----+----+----+----+----+
586 * | NLPID (8 bits) | NLPID=0xb1
587 * +----+----+----+----+----+----+----+----+
588 * | B | E | C |seq. (high 4 bits) | R |
589 * +----+----+----+----+----+----+----+----+
590 * | sequence (low 8 bits) |
591 * +----+----+----+----+----+----+----+----+
592 */
593
594 #define FR_FRF15_FRAGTYPE 0x01
595
596 static void
frf15_print(netdissect_options * ndo,const u_char * p,u_int length)597 frf15_print(netdissect_options *ndo,
598 const u_char *p, u_int length)
599 {
600 uint16_t sequence_num, flags;
601
602 flags = p[0]&MFR_BEC_MASK;
603 sequence_num = (p[0]&0x1e)<<7 | p[1];
604
605 ND_PRINT((ndo, "FRF.15, seq 0x%03x, Flags [%s],%s Fragmentation, length %u",
606 sequence_num,
607 bittok2str(frf_flag_values,"none",flags),
608 p[0]&FR_FRF15_FRAGTYPE ? "Interface" : "End-to-End",
609 length));
610
611 /* TODO:
612 * depending on all permutations of the B, E and C bit
613 * dig as deep as we can - e.g. on the first (B) fragment
614 * there is enough payload to print the IP header
615 * on non (B) fragments it depends if the fragmentation
616 * model is end-to-end or interface based wether we want to print
617 * another Q.922 header
618 */
619
620 }
621
622 /*
623 * Q.933 decoding portion for framerelay specific.
624 */
625
626 /* Q.933 packet format
627 Format of Other Protocols
628 using Q.933 NLPID
629 +-------------------------------+
630 | Q.922 Address |
631 +---------------+---------------+
632 |Control 0x03 | NLPID 0x08 |
633 +---------------+---------------+
634 | L2 Protocol ID |
635 | octet 1 | octet 2 |
636 +-------------------------------+
637 | L3 Protocol ID |
638 | octet 2 | octet 2 |
639 +-------------------------------+
640 | Protocol Data |
641 +-------------------------------+
642 | FCS |
643 +-------------------------------+
644 */
645
646 /* L2 (Octet 1)- Call Reference Usually is 0x0 */
647
648 /*
649 * L2 (Octet 2)- Message Types definition 1 byte long.
650 */
651 /* Call Establish */
652 #define MSG_TYPE_ESC_TO_NATIONAL 0x00
653 #define MSG_TYPE_ALERT 0x01
654 #define MSG_TYPE_CALL_PROCEEDING 0x02
655 #define MSG_TYPE_CONNECT 0x07
656 #define MSG_TYPE_CONNECT_ACK 0x0F
657 #define MSG_TYPE_PROGRESS 0x03
658 #define MSG_TYPE_SETUP 0x05
659 /* Call Clear */
660 #define MSG_TYPE_DISCONNECT 0x45
661 #define MSG_TYPE_RELEASE 0x4D
662 #define MSG_TYPE_RELEASE_COMPLETE 0x5A
663 #define MSG_TYPE_RESTART 0x46
664 #define MSG_TYPE_RESTART_ACK 0x4E
665 /* Status */
666 #define MSG_TYPE_STATUS 0x7D
667 #define MSG_TYPE_STATUS_ENQ 0x75
668
669 static const struct tok fr_q933_msg_values[] = {
670 { MSG_TYPE_ESC_TO_NATIONAL, "ESC to National" },
671 { MSG_TYPE_ALERT, "Alert" },
672 { MSG_TYPE_CALL_PROCEEDING, "Call proceeding" },
673 { MSG_TYPE_CONNECT, "Connect" },
674 { MSG_TYPE_CONNECT_ACK, "Connect ACK" },
675 { MSG_TYPE_PROGRESS, "Progress" },
676 { MSG_TYPE_SETUP, "Setup" },
677 { MSG_TYPE_DISCONNECT, "Disconnect" },
678 { MSG_TYPE_RELEASE, "Release" },
679 { MSG_TYPE_RELEASE_COMPLETE, "Release Complete" },
680 { MSG_TYPE_RESTART, "Restart" },
681 { MSG_TYPE_RESTART_ACK, "Restart ACK" },
682 { MSG_TYPE_STATUS, "Status Reply" },
683 { MSG_TYPE_STATUS_ENQ, "Status Enquiry" },
684 { 0, NULL }
685 };
686
687 #define MSG_ANSI_LOCKING_SHIFT 0x95
688
689 #define FR_LMI_ANSI_REPORT_TYPE_IE 0x01
690 #define FR_LMI_ANSI_LINK_VERIFY_IE_91 0x19 /* details? */
691 #define FR_LMI_ANSI_LINK_VERIFY_IE 0x03
692 #define FR_LMI_ANSI_PVC_STATUS_IE 0x07
693
694 #define FR_LMI_CCITT_REPORT_TYPE_IE 0x51
695 #define FR_LMI_CCITT_LINK_VERIFY_IE 0x53
696 #define FR_LMI_CCITT_PVC_STATUS_IE 0x57
697
698 static const struct tok fr_q933_ie_values_codeset5[] = {
699 { FR_LMI_ANSI_REPORT_TYPE_IE, "ANSI Report Type" },
700 { FR_LMI_ANSI_LINK_VERIFY_IE_91, "ANSI Link Verify" },
701 { FR_LMI_ANSI_LINK_VERIFY_IE, "ANSI Link Verify" },
702 { FR_LMI_ANSI_PVC_STATUS_IE, "ANSI PVC Status" },
703 { FR_LMI_CCITT_REPORT_TYPE_IE, "CCITT Report Type" },
704 { FR_LMI_CCITT_LINK_VERIFY_IE, "CCITT Link Verify" },
705 { FR_LMI_CCITT_PVC_STATUS_IE, "CCITT PVC Status" },
706 { 0, NULL }
707 };
708
709 #define FR_LMI_REPORT_TYPE_IE_FULL_STATUS 0
710 #define FR_LMI_REPORT_TYPE_IE_LINK_VERIFY 1
711 #define FR_LMI_REPORT_TYPE_IE_ASYNC_PVC 2
712
713 static const struct tok fr_lmi_report_type_ie_values[] = {
714 { FR_LMI_REPORT_TYPE_IE_FULL_STATUS, "Full Status" },
715 { FR_LMI_REPORT_TYPE_IE_LINK_VERIFY, "Link verify" },
716 { FR_LMI_REPORT_TYPE_IE_ASYNC_PVC, "Async PVC Status" },
717 { 0, NULL }
718 };
719
720 /* array of 16 codepages - currently we only support codepage 1,5 */
721 static const struct tok *fr_q933_ie_codesets[] = {
722 NULL,
723 fr_q933_ie_values_codeset5,
724 NULL,
725 NULL,
726 NULL,
727 fr_q933_ie_values_codeset5,
728 NULL,
729 NULL,
730 NULL,
731 NULL,
732 NULL,
733 NULL,
734 NULL,
735 NULL,
736 NULL,
737 NULL
738 };
739
740 static int fr_q933_print_ie_codeset5(netdissect_options *ndo,
741 const struct ie_tlv_header_t *ie_p, const u_char *p);
742
743 typedef int (*codeset_pr_func_t)(netdissect_options *,
744 const struct ie_tlv_header_t *ie_p, const u_char *p);
745
746 /* array of 16 codepages - currently we only support codepage 1,5 */
747 static const codeset_pr_func_t fr_q933_print_ie_codeset[] = {
748 NULL,
749 fr_q933_print_ie_codeset5,
750 NULL,
751 NULL,
752 NULL,
753 fr_q933_print_ie_codeset5,
754 NULL,
755 NULL,
756 NULL,
757 NULL,
758 NULL,
759 NULL,
760 NULL,
761 NULL,
762 NULL,
763 NULL
764 };
765
766 void
q933_print(netdissect_options * ndo,const u_char * p,u_int length)767 q933_print(netdissect_options *ndo,
768 const u_char *p, u_int length)
769 {
770 const u_char *ptemp = p;
771 struct ie_tlv_header_t *ie_p;
772 int olen;
773 int is_ansi = 0;
774 u_int codeset;
775 u_int ie_is_known = 0;
776
777 if (length < 9) { /* shortest: Q.933a LINK VERIFY */
778 ND_PRINT((ndo, "[|q.933]"));
779 return;
780 }
781
782 codeset = p[2]&0x0f; /* extract the codeset */
783
784 if (p[2] == MSG_ANSI_LOCKING_SHIFT) {
785 is_ansi = 1;
786 }
787
788 ND_PRINT((ndo, "%s", ndo->ndo_eflag ? "" : "Q.933, "));
789
790 /* printing out header part */
791 ND_PRINT((ndo, "%s, codeset %u", is_ansi ? "ANSI" : "CCITT", codeset));
792
793 if (p[0]) {
794 ND_PRINT((ndo, ", Call Ref: 0x%02x", p[0]));
795 }
796 if (ndo->ndo_vflag) {
797 ND_PRINT((ndo, ", %s (0x%02x), length %u",
798 tok2str(fr_q933_msg_values,
799 "unknown message", p[1]),
800 p[1],
801 length));
802 } else {
803 ND_PRINT((ndo, ", %s",
804 tok2str(fr_q933_msg_values,
805 "unknown message 0x%02x", p[1])));
806 }
807
808 olen = length; /* preserve the original length for non verbose mode */
809
810 if (length < (u_int)(2 - is_ansi)) {
811 ND_PRINT((ndo, "[|q.933]"));
812 return;
813 }
814 length -= 2 + is_ansi;
815 ptemp += 2 + is_ansi;
816
817 /* Loop through the rest of IE */
818 while (length > sizeof(struct ie_tlv_header_t)) {
819 ie_p = (struct ie_tlv_header_t *)ptemp;
820 if (length < sizeof(struct ie_tlv_header_t) ||
821 length < sizeof(struct ie_tlv_header_t) + ie_p->ie_len) {
822 if (ndo->ndo_vflag) { /* not bark if there is just a trailer */
823 ND_PRINT((ndo, "\n[|q.933]"));
824 } else {
825 ND_PRINT((ndo, ", length %u", olen));
826 }
827 return;
828 }
829
830 /* lets do the full IE parsing only in verbose mode
831 * however some IEs (DLCI Status, Link Verify)
832 * are also interestting in non-verbose mode */
833 if (ndo->ndo_vflag) {
834 ND_PRINT((ndo, "\n\t%s IE (0x%02x), length %u: ",
835 tok2str(fr_q933_ie_codesets[codeset],
836 "unknown", ie_p->ie_type),
837 ie_p->ie_type,
838 ie_p->ie_len));
839 }
840
841 /* sanity check */
842 if (ie_p->ie_type == 0 || ie_p->ie_len == 0) {
843 return;
844 }
845
846 if (fr_q933_print_ie_codeset[codeset] != NULL) {
847 ie_is_known = fr_q933_print_ie_codeset[codeset](ndo, ie_p, ptemp);
848 }
849
850 if (ndo->ndo_vflag >= 1 && !ie_is_known) {
851 print_unknown_data(ndo, ptemp+2, "\n\t", ie_p->ie_len);
852 }
853
854 /* do we want to see a hexdump of the IE ? */
855 if (ndo->ndo_vflag> 1 && ie_is_known) {
856 print_unknown_data(ndo, ptemp+2, "\n\t ", ie_p->ie_len);
857 }
858
859 length = length - ie_p->ie_len - 2;
860 ptemp = ptemp + ie_p->ie_len + 2;
861 }
862 if (!ndo->ndo_vflag) {
863 ND_PRINT((ndo, ", length %u", olen));
864 }
865 }
866
867 static int
fr_q933_print_ie_codeset5(netdissect_options * ndo,const struct ie_tlv_header_t * ie_p,const u_char * p)868 fr_q933_print_ie_codeset5(netdissect_options *ndo,
869 const struct ie_tlv_header_t *ie_p, const u_char *p)
870 {
871 u_int dlci;
872
873 switch (ie_p->ie_type) {
874
875 case FR_LMI_ANSI_REPORT_TYPE_IE: /* fall through */
876 case FR_LMI_CCITT_REPORT_TYPE_IE:
877 if (ndo->ndo_vflag) {
878 ND_PRINT((ndo, "%s (%u)",
879 tok2str(fr_lmi_report_type_ie_values,"unknown",p[2]),
880 p[2]));
881 }
882 return 1;
883
884 case FR_LMI_ANSI_LINK_VERIFY_IE: /* fall through */
885 case FR_LMI_CCITT_LINK_VERIFY_IE:
886 case FR_LMI_ANSI_LINK_VERIFY_IE_91:
887 if (!ndo->ndo_vflag) {
888 ND_PRINT((ndo, ", "));
889 }
890 ND_PRINT((ndo, "TX Seq: %3d, RX Seq: %3d", p[2], p[3]));
891 return 1;
892
893 case FR_LMI_ANSI_PVC_STATUS_IE: /* fall through */
894 case FR_LMI_CCITT_PVC_STATUS_IE:
895 if (!ndo->ndo_vflag) {
896 ND_PRINT((ndo, ", "));
897 }
898 /* now parse the DLCI information element. */
899 if ((ie_p->ie_len < 3) ||
900 (p[2] & 0x80) ||
901 ((ie_p->ie_len == 3) && !(p[3] & 0x80)) ||
902 ((ie_p->ie_len == 4) && ((p[3] & 0x80) || !(p[4] & 0x80))) ||
903 ((ie_p->ie_len == 5) && ((p[3] & 0x80) || (p[4] & 0x80) ||
904 !(p[5] & 0x80))) ||
905 (ie_p->ie_len > 5) ||
906 !(p[ie_p->ie_len + 1] & 0x80)) {
907 ND_PRINT((ndo, "Invalid DLCI IE"));
908 }
909
910 dlci = ((p[2] & 0x3F) << 4) | ((p[3] & 0x78) >> 3);
911 if (ie_p->ie_len == 4) {
912 dlci = (dlci << 6) | ((p[4] & 0x7E) >> 1);
913 }
914 else if (ie_p->ie_len == 5) {
915 dlci = (dlci << 13) | (p[4] & 0x7F) | ((p[5] & 0x7E) >> 1);
916 }
917
918 ND_PRINT((ndo, "DLCI %u: status %s%s", dlci,
919 p[ie_p->ie_len + 1] & 0x8 ? "New, " : "",
920 p[ie_p->ie_len + 1] & 0x2 ? "Active" : "Inactive"));
921 return 1;
922 }
923
924 return 0;
925 }
926 /*
927 * Local Variables:
928 * c-style: whitesmith
929 * c-basic-offset: 8
930 * End:
931 */
932