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[tcpdump] / print-fr.c
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
22 #ifndef lint
23 static const char rcsid[] =
24 "@(#)$Header: /tcpdump/master/tcpdump/print-fr.c,v 1.3 2002-07-16 04:09:27 guy Exp $ (LBL)";
25 #endif
26
27 #ifdef HAVE_CONFIG_H
28 #include "config.h"
29 #endif
30
31 #include <sys/param.h>
32 #include <sys/time.h>
33 #include <sys/socket.h>
34
35 struct mbuf;
36 struct rtentry;
37
38 #include <netinet/in.h>
39
40 #include <stdio.h>
41 #include <string.h>
42 #include <pcap.h>
43
44 #include "interface.h"
45 #include "addrtoname.h"
46 #include "ethertype.h"
47 #include "extract.h"
48
49 static void q933_print(const u_char *, int);
50
51 #define FR_CR_BIT 0x02
52 #define FR_EA_BIT(p) ((p)&0x01)
53 #define FR_FECN 0x08
54 #define FR_BECN 0x04
55 #define FR_DE 0x02
56 #define FR_DLCI(b0, b1) ((((b0)&0xFC)<<2)+(((b1)&0xF0)>>4))
57
58 /* find out how many bytes are there in a frame */
59 static int
60 fr_addr_len(const u_char *p)
61 {
62 int i=0;
63
64 while (!FR_EA_BIT(p[i]) && i++ && !FR_EA_BIT(p[i+1])) i++;
65 return (i+1);
66 }
67
68 /* the following is for framerelay */
69 #define NLPID_LEN 1 /* NLPID is one byte long */
70 #define NLPID_Q933 0x08
71 #define NLPID_LMI 0x09
72 #define NLPID_SNAP 0x80
73 #define NLPID_CLNP 0x81
74 #define NLPID_ESIS 0x82
75 #define NLPID_ISIS 0x83
76 #define NLPID_CONS 0x84
77 #define NLPID_IDRP 0x85
78 #define NLPID_X25_ESIS 0x8a
79 #define NLPID_IP 0xcc
80
81
82 static const char *fr_nlpids[256];
83
84 static void
85 init_fr_nlpids(void)
86 {
87 int i;
88 static int fr_nlpid_flag = 0;
89
90 if (!fr_nlpid_flag) {
91 for (i=0; i < 256; i++)
92 fr_nlpids[i] = NULL;
93 fr_nlpids[NLPID_Q933] = "Q.933";
94 fr_nlpids[NLPID_LMI] = "LMI";
95 fr_nlpids[NLPID_SNAP] = "SNAP";
96 fr_nlpids[NLPID_CLNP] = "CLNP";
97 fr_nlpids[NLPID_ESIS] = "ESIS";
98 fr_nlpids[NLPID_ISIS] = "ISIS";
99 fr_nlpids[NLPID_CONS] = "CONS";
100 fr_nlpids[NLPID_IDRP] = "IDRP";
101 fr_nlpids[NLPID_X25_ESIS] = "X25_ESIS";
102 fr_nlpids[NLPID_IP] = "IP";
103 }
104 fr_nlpid_flag = 1;
105 }
106
107 /* Framerelay packet structure */
108
109 /*
110 +---------------------------+
111 | flag (7E hexadecimal) |
112 +---------------------------+
113 | Q.922 Address* |
114 +-- --+
115 | |
116 +---------------------------+
117 | Control (UI = 0x03) |
118 +---------------------------+
119 | Optional Pad (0x00) |
120 +---------------------------+
121 | NLPID |
122 +---------------------------+
123 | . |
124 | . |
125 | . |
126 | Data |
127 | . |
128 | . |
129 +---------------------------+
130 | Frame Check Sequence |
131 +-- . --+
132 | (two octets) |
133 +---------------------------+
134 | flag (7E hexadecimal) |
135 +---------------------------+
136
137 * Q.922 addresses, as presently defined, are two octets and
138 contain a 10-bit DLCI. In some networks Q.922 addresses
139 may optionally be increased to three or four octets.
140
141 */
142
143 #define FR_PROTOCOL(p) fr_protocol((p))
144
145 static int
146 fr_hdrlen(const u_char *p)
147 {
148 int hlen;
149 hlen = fr_addr_len(p)+1; /* addr_len + 0x03 + padding */
150 if (p[hlen])
151 return hlen;
152 else
153 return hlen+1;
154 }
155
156 #define LAYER2_LEN(p) (fr_hdrlen((p))+NLPID_LEN)
157
158 static int
159 fr_protocol(const u_char *p)
160 {
161 int hlen;
162
163 hlen = fr_addr_len(p) + 1;
164 if (p[hlen]) /* check for padding */
165 return p[hlen];
166 else
167 return p[hlen+1];
168 }
169
170 static char *
171 fr_flags(const u_char *p)
172 {
173 static char flags[1+1+4+1+4+1+2+1];
174
175 if (p[0] & FR_CR_BIT)
176 strcpy(flags, "C");
177 else
178 strcpy(flags, "R");
179 if (p[1] & FR_FECN)
180 strcat(flags, ",FECN");
181 if (p[1] & FR_BECN)
182 strcat(flags, ",BECN");
183 if (p[1] & FR_DE)
184 strcat(flags, ",DE");
185 return flags;
186 }
187
188 static const char *
189 fr_protostring(u_int8_t proto)
190 {
191 static char buf[5+1+2+1];
192
193 if (nflag || fr_nlpids[proto] == NULL) {
194 sprintf(buf, "proto-%02x", proto);
195 return buf;
196 }
197 return fr_nlpids[proto];
198 }
199
200 static void
201 fr_hdr_print(const u_char *p, int length)
202 {
203 u_int8_t proto;
204
205 proto = FR_PROTOCOL(p);
206
207 init_fr_nlpids();
208 /* this is kinda kludge since it assumed that DLCI is two bytes. */
209 if (qflag)
210 (void)printf("DLCI-%u-%s %d: ",
211 FR_DLCI(p[0], p[1]), fr_flags(p), length);
212 else
213 (void)printf("DLCI-%u-%s %s %d: ",
214 FR_DLCI(p[0], p[1]), fr_flags(p),
215 fr_protostring(proto), length);
216 }
217
218 void
219 fr_if_print(u_char *user, const struct pcap_pkthdr *h,
220 register const u_char *p)
221 {
222 register u_int length = h->len;
223 register u_int caplen = h->caplen;
224 u_char protocol;
225 int layer2_len;
226 u_short extracted_ethertype;
227 u_int32_t orgcode;
228 register u_short et;
229
230 ts_print(&h->ts);
231
232 if (caplen < fr_hdrlen(p)) {
233 printf("[|fr]");
234 goto out;
235 }
236
237 /*
238 * Some printers want to get back at the link level addresses,
239 * and/or check that they're not walking off the end of the packet.
240 * Rather than pass them all the way down, we set these globals.
241 */
242 packetp = p;
243 snapend = p + caplen;
244
245 if (eflag)
246 fr_hdr_print(p, length);
247
248 protocol = FR_PROTOCOL(p);
249 layer2_len = LAYER2_LEN(p);
250 p += layer2_len;
251 length -= layer2_len;
252 caplen -= layer2_len;
253
254 switch (protocol) {
255
256 case NLPID_IP:
257 ip_print(p, length);
258 break;
259
260 case NLPID_CLNP:
261 case NLPID_ESIS:
262 case NLPID_ISIS:
263 isoclns_print(p, length, caplen, NULL, NULL);
264 break;
265
266 case NLPID_SNAP:
267 orgcode = EXTRACT_24BITS(p);
268 et = EXTRACT_16BITS(p + 3);
269 if (snap_print((const u_char *)(p + 5), length - 5,
270 caplen - 5, NULL, NULL,
271 &extracted_ethertype, orgcode, et, 0) == 0) {
272 /* ether_type not known, print raw packet */
273 if (!eflag)
274 fr_hdr_print(p - layer2_len, length + layer2_len);
275 if (extracted_ethertype) {
276 printf("(SNAP %s) ",
277 etherproto_string(htons(extracted_ethertype)));
278 }
279 if (!xflag && !qflag)
280 default_print(p - layer2_len, caplen + layer2_len);
281 }
282 break;
283
284 case NLPID_Q933:
285 q933_print(p, length);
286 break;
287
288 default:
289 if (!eflag)
290 fr_hdr_print(p - layer2_len, length + layer2_len);
291 if (!xflag)
292 default_print(p, caplen);
293 }
294
295 if (xflag)
296 default_print(p, caplen);
297 out:
298 putchar('\n');
299 }
300
301 /*
302 * Q.933 decoding portion for framerelay specific.
303 */
304
305 /* Q.933 packet format
306 Format of Other Protocols
307 using Q.933 NLPID
308 +-------------------------------+
309 | Q.922 Address |
310 +---------------+---------------+
311 |Control 0x03 | NLPID 0x08 |
312 +---------------+---------------+
313 | L2 Protocol ID |
314 | octet 1 | octet 2 |
315 +-------------------------------+
316 | L3 Protocol ID |
317 | octet 2 | octet 2 |
318 +-------------------------------+
319 | Protocol Data |
320 +-------------------------------+
321 | FCS |
322 +-------------------------------+
323 */
324
325 /* L2 (Octet 1)- Call Reference Usually is 0x0 */
326
327 /*
328 * L2 (Octet 2)- Message Types definition 1 byte long.
329 */
330 /* Call Establish */
331 #define MSG_TYPE_ESC_TO_NATIONAL 0x00
332 #define MSG_TYPE_ALERT 0x01
333 #define MSG_TYPE_CALL_PROCEEDING 0x02
334 #define MSG_TYPE_CONNECT 0x07
335 #define MSG_TYPE_CONNECT_ACK 0x0F
336 #define MSG_TYPE_PROGRESS 0x03
337 #define MSG_TYPE_SETUP 0x05
338 /* Call Clear */
339 #define MSG_TYPE_DISCONNECT 0x45
340 #define MSG_TYPE_RELEASE 0x4D
341 #define MSG_TYPE_RELEASE_COMPLETE 0x5A
342 #define MSG_TYPE_RESTART 0x46
343 #define MSG_TYPE_RESTART_ACK 0x4E
344 /* Status */
345 #define MSG_TYPE_STATUS 0x7D
346 #define MSG_TYPE_STATUS_ENQ 0x75
347
348 #define ONE_BYTE_IE_MASK 0xF0
349
350 /* See L2 protocol ID picture above */
351 struct q933_header {
352 u_char call_ref; /* usually is 0 for framerelay PVC */
353 u_char msg_type;
354 };
355
356 #define REPORT_TYPE_IE 0x01
357 #define LINK_VERIFY_IE_91 0x19
358 #define LINK_VERIFY_IE_94 0x03
359 #define PVC_STATUS_IE 0x07
360
361 #define MAX_IE_SIZE
362
363 struct common_ie_header {
364 u_char ie_id;
365 u_char ie_len;
366 };
367
368 #define FULL_STATUS 0
369 #define LINK_VERIFY 1
370 #define ASYNC_PVC 2
371
372 static void
373 q933_print(const u_char *p, int length)
374 {
375 struct q933_header *header = (struct q933_header *)(p+1);
376 const u_char *ptemp = p;
377 int ie_len;
378 char *decode_str, temp_str[255];
379 struct common_ie_header *ie_p;
380
381 /* printing out header part */
382 printf("Call Ref: %02x, MSG Type: %02x",
383 header->call_ref, header->msg_type);
384 switch(header->msg_type) {
385 case MSG_TYPE_STATUS:
386 decode_str = "STATUS REPLY";
387 break;
388 case MSG_TYPE_STATUS_ENQ:
389 decode_str = "STATUS ENQUIRY";
390 break;
391 default:
392 decode_str = "UNKNOWN MSG Type";
393 }
394 printf(" %s\n", decode_str);
395
396 length = length - 3;
397 ptemp = ptemp + 3;
398
399 /* Loop through the rest of IE */
400 while( length > 0 ) {
401 if (ptemp[0] & ONE_BYTE_IE_MASK) {
402 ie_len = 1;
403 printf("\t\tOne byte IE: %02x, Content %02x\n",
404 (*ptemp & 0x70)>>4, (*ptemp & 0x0F));
405 length--;
406 ptemp++;
407 }
408 else { /* Multi-byte IE */
409 ie_p = (struct common_ie_header *)ptemp;
410 switch (ie_p->ie_id) {
411 case REPORT_TYPE_IE:
412 switch(ptemp[2]) {
413 case FULL_STATUS:
414 decode_str = "FULL STATUS";
415 break;
416 case LINK_VERIFY:
417 decode_str = "LINK VERIFY";
418 break;
419 case ASYNC_PVC:
420 decode_str = "Async PVC Status";
421 break;
422 default:
423 decode_str = "Reserved Value";
424 }
425 break;
426 case LINK_VERIFY_IE_91:
427 case LINK_VERIFY_IE_94:
428 snprintf(temp_str, sizeof (temp_str), "TX Seq: %3d, RX Seq: %3d",
429 ptemp[2], ptemp[3]);
430 decode_str = temp_str;
431 break;
432 case PVC_STATUS_IE:
433 snprintf(temp_str, sizeof (temp_str), "DLCI %d: status %s %s",
434 ((ptemp[2]&0x3f)<<4)+ ((ptemp[3]&0x78)>>3),
435 ptemp[4] & 0x8 ?"new,":" ",
436 ptemp[4] & 0x2 ?"Active":"Inactive");
437 break;
438 default:
439 decode_str = "Non-decoded Value";
440 }
441 printf("\t\tIE: %02X Len: %d, %s\n",
442 ie_p->ie_id, ie_p->ie_len, decode_str);
443 length = length - ie_p->ie_len - 2;
444 ptemp = ptemp + ie_p->ie_len + 2;
445 }
446 }
447 }
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