xref: /freebsd/contrib/tcpdump/print-fr.c (revision d056fa046c6a91b90cd98165face0e42a33a5173)
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 #ifndef lint
25 static const char rcsid[] _U_ =
26 	"@(#)$Header: /tcpdump/master/tcpdump/print-fr.c,v 1.32.2.4 2005/05/27 14:56:52 hannes Exp $ (LBL)";
27 #endif
28 
29 #ifdef HAVE_CONFIG_H
30 #include "config.h"
31 #endif
32 
33 #include <tcpdump-stdinc.h>
34 
35 #include <stdio.h>
36 #include <string.h>
37 #include <pcap.h>
38 
39 #include "addrtoname.h"
40 #include "interface.h"
41 #include "ethertype.h"
42 #include "nlpid.h"
43 #include "extract.h"
44 #include "oui.h"
45 
46 static void frf15_print(const u_char *, u_int);
47 
48 /*
49  * the frame relay header has a variable length
50  *
51  * the EA bit determines if there is another byte
52  * in the header
53  *
54  * minimum header length is 2 bytes
55  * maximum header length is 4 bytes
56  *
57  *      7    6    5    4    3    2    1    0
58  *    +----+----+----+----+----+----+----+----+
59  *    |        DLCI (6 bits)        | CR | EA |
60  *    +----+----+----+----+----+----+----+----+
61  *    |   DLCI (4 bits)   |FECN|BECN| DE | EA |
62  *    +----+----+----+----+----+----+----+----+
63  *    |           DLCI (7 bits)          | EA |
64  *    +----+----+----+----+----+----+----+----+
65  *    |        DLCI (6 bits)        |SDLC| EA |
66  *    +----+----+----+----+----+----+----+----+
67  */
68 
69 #define FR_EA_BIT	0x01
70 
71 #define FR_CR_BIT       0x02000000
72 #define FR_DE_BIT	0x00020000
73 #define FR_BECN_BIT	0x00040000
74 #define FR_FECN_BIT	0x00080000
75 #define FR_SDLC_BIT	0x00000002
76 
77 
78 struct tok fr_header_flag_values[] = {
79     { FR_CR_BIT, "C!" },
80     { FR_DE_BIT, "DE" },
81     { FR_BECN_BIT, "BECN" },
82     { FR_FECN_BIT, "FECN" },
83     { FR_SDLC_BIT, "sdlcore" },
84     { 0, NULL }
85 };
86 
87 
88 /* Finds out Q.922 address length, DLCI and flags. Returns 0 on success
89  * save the flags dep. on address length
90  */
91 static int parse_q922_addr(const u_char *p, u_int *dlci, u_int *sdlcore,
92                            u_int *addr_len, u_int8_t *flags)
93 {
94 	if ((p[0] & FR_EA_BIT))
95 		return -1;
96 
97 	*addr_len = 2;
98 	*dlci = ((p[0] & 0xFC) << 2) | ((p[1] & 0xF0) >> 4);
99 
100         flags[0] = p[0] & 0x02; /* populate the first flag fields */
101         flags[1] = p[1] & 0x0c;
102 
103 	if (p[1] & FR_EA_BIT)
104 		return 0;	/* 2-byte Q.922 address */
105 
106 	p += 2;
107 	(*addr_len)++;		/* 3- or 4-byte Q.922 address */
108 	if ((p[0] & FR_EA_BIT) == 0) {
109 		*dlci = (*dlci << 7) | (p[0] >> 1);
110 		(*addr_len)++;	/* 4-byte Q.922 address */
111 		p++;
112 	}
113 
114 	if ((p[0] & FR_EA_BIT) == 0)
115 		return -1; /* more than 4 bytes of Q.922 address? */
116 
117         flags[3] = p[0] & 0x02;
118 
119 	if (p[0] & 0x02)
120                 *sdlcore =  p[0] >> 2;
121 	else
122 		*dlci = (*dlci << 6) | (p[0] >> 2);
123 
124 	return 0;
125 }
126 
127 /* Frame Relay packet structure, with flags and CRC removed
128 
129                   +---------------------------+
130                   |       Q.922 Address*      |
131                   +--                       --+
132                   |                           |
133                   +---------------------------+
134                   | Control (UI = 0x03)       |
135                   +---------------------------+
136                   | Optional Pad      (0x00)  |
137                   +---------------------------+
138                   | NLPID                     |
139                   +---------------------------+
140                   |             .             |
141                   |             .             |
142                   |             .             |
143                   |           Data            |
144                   |             .             |
145                   |             .             |
146                   +---------------------------+
147 
148            * Q.922 addresses, as presently defined, are two octets and
149              contain a 10-bit DLCI.  In some networks Q.922 addresses
150              may optionally be increased to three or four octets.
151 */
152 
153 static u_int
154 fr_hdrlen(const u_char *p, u_int addr_len)
155 {
156 	if (!p[addr_len + 1] /* pad exist */)
157 		return addr_len + 1 /* UI */ + 1 /* pad */ + 1 /* NLPID */;
158 	else
159 		return addr_len + 1 /* UI */ + 1 /* NLPID */;
160 }
161 
162 static void
163 fr_hdr_print(int length, u_int addr_len, u_int dlci, u_int8_t *flags, u_int16_t nlpid)
164 {
165     if (qflag) {
166         (void)printf("Q.922, DLCI %u, length %u: ",
167                      dlci,
168                      length);
169     } else {
170         if (nlpid <= 0xff) /* if its smaller than 256 then its a NLPID */
171             (void)printf("Q.922, hdr-len %u, DLCI %u, Flags [%s], NLPID %s (0x%02x), length %u: ",
172                          addr_len,
173                          dlci,
174                          bittok2str(fr_header_flag_values, "none", EXTRACT_32BITS(flags)),
175                          tok2str(nlpid_values,"unknown", nlpid),
176                          nlpid,
177                          length);
178         else /* must be an ethertype */
179             (void)printf("Q.922, hdr-len %u, DLCI %u, Flags [%s], cisco-ethertype %s (0x%04x), length %u: ",
180                          addr_len,
181                          dlci,
182                          bittok2str(fr_header_flag_values, "none", EXTRACT_32BITS(flags)),
183                          tok2str(ethertype_values, "unknown", nlpid),
184                          nlpid,
185                          length);
186     }
187 }
188 
189 u_int
190 fr_if_print(const struct pcap_pkthdr *h, register const u_char *p)
191 {
192 	register u_int length = h->len;
193 	register u_int caplen = h->caplen;
194 
195         TCHECK2(*p, 4); /* minimum frame header length */
196 
197         if ((length = fr_print(p, length)) == 0)
198             return (0);
199         else
200             return length;
201  trunc:
202         printf("[|fr]");
203         return caplen;
204 }
205 
206 u_int
207 fr_print(register const u_char *p, u_int length)
208 {
209 	u_int16_t extracted_ethertype;
210 	u_int dlci;
211         u_int sdlcore;
212 	u_int addr_len;
213 	u_int16_t nlpid;
214 	u_int hdr_len;
215 	u_int8_t flags[4];
216 
217 	if (parse_q922_addr(p, &dlci, &sdlcore, &addr_len, flags)) {
218 		printf("Q.922, invalid address");
219 		return 0;
220 	}
221 
222         TCHECK2(*p,addr_len+1+1);
223 	hdr_len = fr_hdrlen(p, addr_len);
224         TCHECK2(*p,hdr_len);
225 
226 	if (p[addr_len] != 0x03 && dlci != 0) {
227 
228                 /* lets figure out if we have cisco style encapsulation: */
229                 extracted_ethertype = EXTRACT_16BITS(p+addr_len);
230 
231                 if (eflag)
232                     fr_hdr_print(length, addr_len, dlci, flags, extracted_ethertype);
233 
234                 if (ether_encap_print(extracted_ethertype,
235                                       p+addr_len+ETHERTYPE_LEN,
236                                       length-addr_len-ETHERTYPE_LEN,
237                                       length-addr_len-ETHERTYPE_LEN,
238                                       &extracted_ethertype) == 0)
239                     /* ether_type not known, probably it wasn't one */
240                     printf("UI %02x! ", p[addr_len]);
241                 else
242                     return hdr_len;
243         }
244 
245 	if (!p[addr_len + 1]) {	/* pad byte should be used with 3-byte Q.922 */
246 		if (addr_len != 3)
247 			printf("Pad! ");
248 	} else if (addr_len == 3)
249 		printf("No pad! ");
250 
251 	nlpid = p[hdr_len - 1];
252 
253 	if (eflag)
254 		fr_hdr_print(length, addr_len, dlci, flags, nlpid);
255 
256 	p += hdr_len;
257 	length -= hdr_len;
258 
259 	switch (nlpid) {
260 	case NLPID_IP:
261 	        ip_print(gndo, p, length);
262 		break;
263 
264 #ifdef INET6
265 	case NLPID_IP6:
266 		ip6_print(p, length);
267 		break;
268 #endif
269 	case NLPID_CLNP:
270 	case NLPID_ESIS:
271 	case NLPID_ISIS:
272                 isoclns_print(p-1, length+1, length+1); /* OSI printers need the NLPID field */
273 		break;
274 
275 	case NLPID_SNAP:
276 		if (snap_print(p, length, length, &extracted_ethertype, 0) == 0) {
277 			/* ether_type not known, print raw packet */
278                         if (!eflag)
279                             fr_hdr_print(length + hdr_len, hdr_len,
280                                          dlci, flags, nlpid);
281 			if (!xflag && !qflag)
282                             default_print(p - hdr_len, length + hdr_len);
283 		}
284 		break;
285 
286         case NLPID_Q933:
287 		q933_print(p, length);
288 		break;
289 
290         case NLPID_MFR:
291                 frf15_print(p, length);
292                 break;
293 
294 	default:
295 		if (!eflag)
296                     fr_hdr_print(length + hdr_len, addr_len,
297 				     dlci, flags, nlpid);
298 		if (!xflag)
299 			default_print(p, length);
300 	}
301 
302 	return hdr_len;
303 
304  trunc:
305         printf("[|fr]");
306         return 0;
307 
308 }
309 
310 /* an NLPID of 0xb1 indicates a 2-byte
311  * FRF.15 header
312  *
313  *      7    6    5    4    3    2    1    0
314  *    +----+----+----+----+----+----+----+----+
315  *    ~              Q.922 header             ~
316  *    +----+----+----+----+----+----+----+----+
317  *    |             NLPID (8 bits)            | NLPID=0xb1
318  *    +----+----+----+----+----+----+----+----+
319  *    | B  | E  | C  |seq. (high 4 bits) | R  |
320  *    +----+----+----+----+----+----+----+----+
321  *    |        sequence  (low 8 bits)         |
322  *    +----+----+----+----+----+----+----+----+
323  */
324 
325 struct tok frf15_flag_values[] = {
326     { 0x80, "Begin" },
327     { 0x40, "End" },
328     { 0x20, "Control" },
329     { 0, NULL }
330 };
331 
332 #define FR_FRF15_FRAGTYPE 0x01
333 
334 static void
335 frf15_print (const u_char *p, u_int length) {
336 
337     u_int16_t sequence_num, flags;
338 
339     flags = p[0]&0xe0;
340     sequence_num = (p[0]&0x1e)<<7 | p[1];
341 
342     printf("FRF.15, seq 0x%03x, Flags [%s],%s Fragmentation, length %u",
343            sequence_num,
344            bittok2str(frf15_flag_values,"none",flags),
345            flags&FR_FRF15_FRAGTYPE ? "Interface" : "End-to-End",
346            length);
347 
348 /* TODO:
349  * depending on all permutations of the B, E and C bit
350  * dig as deep as we can - e.g. on the first (B) fragment
351  * there is enough payload to print the IP header
352  * on non (B) fragments it depends if the fragmentation
353  * model is end-to-end or interface based wether we want to print
354  * another Q.922 header
355  */
356 
357 }
358 
359 /*
360  * Q.933 decoding portion for framerelay specific.
361  */
362 
363 /* Q.933 packet format
364                       Format of Other Protocols
365                           using Q.933 NLPID
366                   +-------------------------------+
367                   |        Q.922 Address          |
368                   +---------------+---------------+
369                   |Control  0x03  | NLPID   0x08  |
370                   +---------------+---------------+
371                   |          L2 Protocol ID       |
372                   | octet 1       |  octet 2      |
373                   +-------------------------------+
374                   |          L3 Protocol ID       |
375                   | octet 2       |  octet 2      |
376                   +-------------------------------+
377                   |         Protocol Data         |
378                   +-------------------------------+
379                   | FCS                           |
380                   +-------------------------------+
381  */
382 
383 /* L2 (Octet 1)- Call Reference Usually is 0x0 */
384 
385 /*
386  * L2 (Octet 2)- Message Types definition 1 byte long.
387  */
388 /* Call Establish */
389 #define MSG_TYPE_ESC_TO_NATIONAL  0x00
390 #define MSG_TYPE_ALERT            0x01
391 #define MSG_TYPE_CALL_PROCEEDING  0x02
392 #define MSG_TYPE_CONNECT          0x07
393 #define MSG_TYPE_CONNECT_ACK      0x0F
394 #define MSG_TYPE_PROGRESS         0x03
395 #define MSG_TYPE_SETUP            0x05
396 /* Call Clear */
397 #define MSG_TYPE_DISCONNECT       0x45
398 #define MSG_TYPE_RELEASE          0x4D
399 #define MSG_TYPE_RELEASE_COMPLETE 0x5A
400 #define MSG_TYPE_RESTART          0x46
401 #define MSG_TYPE_RESTART_ACK      0x4E
402 /* Status */
403 #define MSG_TYPE_STATUS           0x7D
404 #define MSG_TYPE_STATUS_ENQ       0x75
405 
406 struct tok fr_q933_msg_values[] = {
407     { MSG_TYPE_ESC_TO_NATIONAL, "ESC to National" },
408     { MSG_TYPE_ALERT, "Alert" },
409     { MSG_TYPE_CALL_PROCEEDING, "Call proceeding" },
410     { MSG_TYPE_CONNECT, "Connect" },
411     { MSG_TYPE_CONNECT_ACK, "Connect ACK" },
412     { MSG_TYPE_PROGRESS, "Progress" },
413     { MSG_TYPE_SETUP, "Setup" },
414     { MSG_TYPE_DISCONNECT, "Disconnect" },
415     { MSG_TYPE_RELEASE, "Release" },
416     { MSG_TYPE_RELEASE_COMPLETE, "Release Complete" },
417     { MSG_TYPE_RESTART, "Restart" },
418     { MSG_TYPE_RESTART_ACK, "Restart ACK" },
419     { MSG_TYPE_STATUS, "Status Reply" },
420     { MSG_TYPE_STATUS_ENQ, "Status Enquiry" },
421     { 0, NULL }
422 };
423 
424 #define MSG_ANSI_LOCKING_SHIFT	0x95
425 
426 #define FR_LMI_ANSI_REPORT_TYPE_IE	0x01
427 #define FR_LMI_ANSI_LINK_VERIFY_IE_91	0x19 /* details? */
428 #define FR_LMI_ANSI_LINK_VERIFY_IE	0x03
429 #define FR_LMI_ANSI_PVC_STATUS_IE	0x07
430 
431 #define FR_LMI_CCITT_REPORT_TYPE_IE	0x51
432 #define FR_LMI_CCITT_LINK_VERIFY_IE	0x53
433 #define FR_LMI_CCITT_PVC_STATUS_IE	0x57
434 
435 struct tok fr_q933_ie_values_codeset5[] = {
436     { FR_LMI_ANSI_REPORT_TYPE_IE, "ANSI Report Type" },
437     { FR_LMI_ANSI_LINK_VERIFY_IE_91, "ANSI Link Verify" },
438     { FR_LMI_ANSI_LINK_VERIFY_IE, "ANSI Link Verify" },
439     { FR_LMI_ANSI_PVC_STATUS_IE, "ANSI PVC Status" },
440     { FR_LMI_CCITT_REPORT_TYPE_IE, "CCITT Report Type" },
441     { FR_LMI_CCITT_LINK_VERIFY_IE, "CCITT Link Verify" },
442     { FR_LMI_CCITT_PVC_STATUS_IE, "CCITT PVC Status" },
443     { 0, NULL }
444 };
445 
446 #define FR_LMI_REPORT_TYPE_IE_FULL_STATUS 0
447 #define FR_LMI_REPORT_TYPE_IE_LINK_VERIFY 1
448 #define FR_LMI_REPORT_TYPE_IE_ASYNC_PVC   2
449 
450 struct tok fr_lmi_report_type_ie_values[] = {
451     { FR_LMI_REPORT_TYPE_IE_FULL_STATUS, "Full Status" },
452     { FR_LMI_REPORT_TYPE_IE_LINK_VERIFY, "Link verify" },
453     { FR_LMI_REPORT_TYPE_IE_ASYNC_PVC, "Async PVC Status" },
454     { 0, NULL }
455 };
456 
457 /* array of 16 codepages - currently we only support codepage 5 */
458 static struct tok *fr_q933_ie_codesets[] = {
459     NULL,
460     NULL,
461     NULL,
462     NULL,
463     NULL,
464     fr_q933_ie_values_codeset5,
465     NULL,
466     NULL,
467     NULL,
468     NULL,
469     NULL,
470     NULL,
471     NULL,
472     NULL,
473     NULL,
474     NULL
475 };
476 
477 
478 struct common_ie_header {
479     u_int8_t ie_id;
480     u_int8_t ie_len;
481 };
482 
483 static int fr_q933_print_ie_codeset5(const struct common_ie_header *ie_p,
484     const u_char *p);
485 
486 typedef int (*codeset_pr_func_t)(const struct common_ie_header *ie_p,
487     const u_char *p);
488 
489 /* array of 16 codepages - currently we only support codepage 5 */
490 static codeset_pr_func_t fr_q933_print_ie_codeset[] = {
491     NULL,
492     NULL,
493     NULL,
494     NULL,
495     NULL,
496     fr_q933_print_ie_codeset5,
497     NULL,
498     NULL,
499     NULL,
500     NULL,
501     NULL,
502     NULL,
503     NULL,
504     NULL,
505     NULL,
506     NULL
507 };
508 
509 void
510 q933_print(const u_char *p, u_int length)
511 {
512 	const u_char *ptemp = p;
513 	struct common_ie_header *ie_p;
514         int olen;
515 	int is_ansi = 0;
516         u_int codeset;
517 
518 	if (length < 9) {	/* shortest: Q.933a LINK VERIFY */
519 		printf("[|q.933]");
520 		return;
521 	}
522 
523         codeset = p[2]&0x0f;   /* extract the codeset */
524 
525 	if (p[2] == MSG_ANSI_LOCKING_SHIFT)
526 		is_ansi = 1;
527 
528         printf("%s", eflag ? "" : "Q.933, ");
529 
530 	/* printing out header part */
531 	printf(is_ansi ? "ANSI" : "CCITT");
532 
533 	if (p[0])
534 		printf(", Call Ref: 0x%02x", p[0]);
535 
536         if (vflag)
537             printf(", %s (0x%02x), length %u",
538                    tok2str(fr_q933_msg_values,"unknown message",p[1]),
539                    p[1],
540                    length);
541         else
542             printf(", %s",
543                    tok2str(fr_q933_msg_values,"unknown message 0x%02x",p[1]));
544 
545         olen = length; /* preserve the original length for non verbose mode */
546 
547 	if (length < (u_int)(2 - is_ansi)) {
548 		printf("[|q.933]");
549 		return;
550 	}
551 	length -= 2 - is_ansi;
552 	ptemp += 2 + is_ansi;
553 
554 	/* Loop through the rest of IE */
555 	while (length > sizeof(struct common_ie_header)) {
556 		ie_p = (struct common_ie_header *)ptemp;
557 		if (length < sizeof(struct common_ie_header) ||
558 		    length < sizeof(struct common_ie_header) + ie_p->ie_len) {
559                     if (vflag) /* not bark if there is just a trailer */
560                         printf("\n[|q.933]");
561                     else
562                         printf(", length %u",olen);
563                     return;
564 		}
565 
566                 /* lets do the full IE parsing only in verbose mode
567                  * however some IEs (DLCI Status, Link Verify)
568                  * are also intereststing in non-verbose mode */
569                 if (vflag)
570                     printf("\n\t%s IE (%u), length %u: ",
571                            tok2str(fr_q933_ie_codesets[codeset],"unknown",ie_p->ie_id),
572                            ie_p->ie_id,
573                            ie_p->ie_len);
574 
575                 if (!fr_q933_print_ie_codeset[codeset] ||
576                     (*fr_q933_print_ie_codeset[codeset])(ie_p, ptemp)) {
577                     if (vflag <= 1)
578                         print_unknown_data(ptemp+2,"\n\t",ie_p->ie_len);
579                 }
580 
581                 /* do we want to see a hexdump of the IE ? */
582                 if (vflag> 1)
583                     print_unknown_data(ptemp+2,"\n\t  ",ie_p->ie_len);
584 
585 		length = length - ie_p->ie_len - 2;
586 		ptemp = ptemp + ie_p->ie_len + 2;
587 	}
588         if (!vflag)
589             printf(", length %u",olen);
590 }
591 
592 static int
593 fr_q933_print_ie_codeset5(const struct common_ie_header *ie_p, const u_char *p)
594 {
595         u_int dlci;
596 
597         switch (ie_p->ie_id) {
598 
599         case FR_LMI_ANSI_REPORT_TYPE_IE: /* fall through */
600         case FR_LMI_CCITT_REPORT_TYPE_IE:
601             if (vflag)
602                 printf("%s (%u)",
603                        tok2str(fr_lmi_report_type_ie_values,"unknown",p[2]),
604                        p[2]);
605             return 1;
606 
607         case FR_LMI_ANSI_LINK_VERIFY_IE: /* fall through */
608         case FR_LMI_CCITT_LINK_VERIFY_IE:
609         case FR_LMI_ANSI_LINK_VERIFY_IE_91:
610             if (!vflag)
611                 printf(", ");
612             printf("TX Seq: %3d, RX Seq: %3d", p[2], p[3]);
613             return 1;
614 
615         case FR_LMI_ANSI_PVC_STATUS_IE: /* fall through */
616         case FR_LMI_CCITT_PVC_STATUS_IE:
617             if (!vflag)
618                 printf(", ");
619             /* now parse the DLCI information element. */
620             if ((ie_p->ie_len < 3) ||
621                 (p[2] & 0x80) ||
622                 ((ie_p->ie_len == 3) && !(p[3] & 0x80)) ||
623                 ((ie_p->ie_len == 4) && ((p[3] & 0x80) || !(p[4] & 0x80))) ||
624                 ((ie_p->ie_len == 5) && ((p[3] & 0x80) || (p[4] & 0x80) ||
625                                    !(p[5] & 0x80))) ||
626                 (ie_p->ie_len > 5) ||
627                 !(p[ie_p->ie_len + 1] & 0x80))
628                 printf("Invalid DLCI IE");
629 
630             dlci = ((p[2] & 0x3F) << 4) | ((p[3] & 0x78) >> 3);
631             if (ie_p->ie_len == 4)
632                 dlci = (dlci << 6) | ((p[4] & 0x7E) >> 1);
633             else if (ie_p->ie_len == 5)
634                 dlci = (dlci << 13) | (p[4] & 0x7F) | ((p[5] & 0x7E) >> 1);
635 
636             printf("DLCI %u: status %s%s", dlci,
637                     p[ie_p->ie_len + 1] & 0x8 ? "New, " : "",
638                     p[ie_p->ie_len + 1] & 0x2 ? "Active" : "Inactive");
639             return 1;
640 	}
641 
642         return 0;
643 }
644