1 /*
2 * Copyright (c) 1991, 1993, 1994, 1995, 1996, 1997
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 * L2TP support contributed by Motonori Shindo (mshindo@mshindo.net)
22 */
23
24 #ifndef lint
25 static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/tcpdump/print-l2tp.c,v 1.20 2006-06-23 02:03:09 hannes Exp $";
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
37 #include "l2tp.h"
38 #include "interface.h"
39 #include "extract.h"
40
41 static char tstr[] = " [|l2tp]";
42
43 #define L2TP_MSGTYPE_SCCRQ 1 /* Start-Control-Connection-Request */
44 #define L2TP_MSGTYPE_SCCRP 2 /* Start-Control-Connection-Reply */
45 #define L2TP_MSGTYPE_SCCCN 3 /* Start-Control-Connection-Connected */
46 #define L2TP_MSGTYPE_STOPCCN 4 /* Stop-Control-Connection-Notification */
47 #define L2TP_MSGTYPE_HELLO 6 /* Hello */
48 #define L2TP_MSGTYPE_OCRQ 7 /* Outgoing-Call-Request */
49 #define L2TP_MSGTYPE_OCRP 8 /* Outgoing-Call-Reply */
50 #define L2TP_MSGTYPE_OCCN 9 /* Outgoing-Call-Connected */
51 #define L2TP_MSGTYPE_ICRQ 10 /* Incoming-Call-Request */
52 #define L2TP_MSGTYPE_ICRP 11 /* Incoming-Call-Reply */
53 #define L2TP_MSGTYPE_ICCN 12 /* Incoming-Call-Connected */
54 #define L2TP_MSGTYPE_CDN 14 /* Call-Disconnect-Notify */
55 #define L2TP_MSGTYPE_WEN 15 /* WAN-Error-Notify */
56 #define L2TP_MSGTYPE_SLI 16 /* Set-Link-Info */
57
58 static const struct tok l2tp_msgtype2str[] = {
59 { L2TP_MSGTYPE_SCCRQ, "SCCRQ" },
60 { L2TP_MSGTYPE_SCCRP, "SCCRP" },
61 { L2TP_MSGTYPE_SCCCN, "SCCCN" },
62 { L2TP_MSGTYPE_STOPCCN, "StopCCN" },
63 { L2TP_MSGTYPE_HELLO, "HELLO" },
64 { L2TP_MSGTYPE_OCRQ, "OCRQ" },
65 { L2TP_MSGTYPE_OCRP, "OCRP" },
66 { L2TP_MSGTYPE_OCCN, "OCCN" },
67 { L2TP_MSGTYPE_ICRQ, "ICRQ" },
68 { L2TP_MSGTYPE_ICRP, "ICRP" },
69 { L2TP_MSGTYPE_ICCN, "ICCN" },
70 { L2TP_MSGTYPE_CDN, "CDN" },
71 { L2TP_MSGTYPE_WEN, "WEN" },
72 { L2TP_MSGTYPE_SLI, "SLI" },
73 { 0, NULL }
74 };
75
76 #define L2TP_AVP_MSGTYPE 0 /* Message Type */
77 #define L2TP_AVP_RESULT_CODE 1 /* Result Code */
78 #define L2TP_AVP_PROTO_VER 2 /* Protocol Version */
79 #define L2TP_AVP_FRAMING_CAP 3 /* Framing Capabilities */
80 #define L2TP_AVP_BEARER_CAP 4 /* Bearer Capabilities */
81 #define L2TP_AVP_TIE_BREAKER 5 /* Tie Breaker */
82 #define L2TP_AVP_FIRM_VER 6 /* Firmware Revision */
83 #define L2TP_AVP_HOST_NAME 7 /* Host Name */
84 #define L2TP_AVP_VENDOR_NAME 8 /* Vendor Name */
85 #define L2TP_AVP_ASSND_TUN_ID 9 /* Assigned Tunnel ID */
86 #define L2TP_AVP_RECV_WIN_SIZE 10 /* Receive Window Size */
87 #define L2TP_AVP_CHALLENGE 11 /* Challenge */
88 #define L2TP_AVP_Q931_CC 12 /* Q.931 Cause Code */
89 #define L2TP_AVP_CHALLENGE_RESP 13 /* Challenge Response */
90 #define L2TP_AVP_ASSND_SESS_ID 14 /* Assigned Session ID */
91 #define L2TP_AVP_CALL_SER_NUM 15 /* Call Serial Number */
92 #define L2TP_AVP_MINIMUM_BPS 16 /* Minimum BPS */
93 #define L2TP_AVP_MAXIMUM_BPS 17 /* Maximum BPS */
94 #define L2TP_AVP_BEARER_TYPE 18 /* Bearer Type */
95 #define L2TP_AVP_FRAMING_TYPE 19 /* Framing Type */
96 #define L2TP_AVP_PACKET_PROC_DELAY 20 /* Packet Processing Delay (OBSOLETE) */
97 #define L2TP_AVP_CALLED_NUMBER 21 /* Called Number */
98 #define L2TP_AVP_CALLING_NUMBER 22 /* Calling Number */
99 #define L2TP_AVP_SUB_ADDRESS 23 /* Sub-Address */
100 #define L2TP_AVP_TX_CONN_SPEED 24 /* (Tx) Connect Speed */
101 #define L2TP_AVP_PHY_CHANNEL_ID 25 /* Physical Channel ID */
102 #define L2TP_AVP_INI_RECV_LCP 26 /* Initial Received LCP CONFREQ */
103 #define L2TP_AVP_LAST_SENT_LCP 27 /* Last Sent LCP CONFREQ */
104 #define L2TP_AVP_LAST_RECV_LCP 28 /* Last Received LCP CONFREQ */
105 #define L2TP_AVP_PROXY_AUTH_TYPE 29 /* Proxy Authen Type */
106 #define L2TP_AVP_PROXY_AUTH_NAME 30 /* Proxy Authen Name */
107 #define L2TP_AVP_PROXY_AUTH_CHAL 31 /* Proxy Authen Challenge */
108 #define L2TP_AVP_PROXY_AUTH_ID 32 /* Proxy Authen ID */
109 #define L2TP_AVP_PROXY_AUTH_RESP 33 /* Proxy Authen Response */
110 #define L2TP_AVP_CALL_ERRORS 34 /* Call Errors */
111 #define L2TP_AVP_ACCM 35 /* ACCM */
112 #define L2TP_AVP_RANDOM_VECTOR 36 /* Random Vector */
113 #define L2TP_AVP_PRIVATE_GRP_ID 37 /* Private Group ID */
114 #define L2TP_AVP_RX_CONN_SPEED 38 /* (Rx) Connect Speed */
115 #define L2TP_AVP_SEQ_REQUIRED 39 /* Sequencing Required */
116 #define L2TP_AVP_PPP_DISCON_CC 46 /* PPP Disconnect Cause Code */
117
118 static const struct tok l2tp_avp2str[] = {
119 { L2TP_AVP_MSGTYPE, "MSGTYPE" },
120 { L2TP_AVP_RESULT_CODE, "RESULT_CODE" },
121 { L2TP_AVP_PROTO_VER, "PROTO_VER" },
122 { L2TP_AVP_FRAMING_CAP, "FRAMING_CAP" },
123 { L2TP_AVP_BEARER_CAP, "BEARER_CAP" },
124 { L2TP_AVP_TIE_BREAKER, "TIE_BREAKER" },
125 { L2TP_AVP_FIRM_VER, "FIRM_VER" },
126 { L2TP_AVP_HOST_NAME, "HOST_NAME" },
127 { L2TP_AVP_VENDOR_NAME, "VENDOR_NAME" },
128 { L2TP_AVP_ASSND_TUN_ID, "ASSND_TUN_ID" },
129 { L2TP_AVP_RECV_WIN_SIZE, "RECV_WIN_SIZE" },
130 { L2TP_AVP_CHALLENGE, "CHALLENGE" },
131 { L2TP_AVP_Q931_CC, "Q931_CC", },
132 { L2TP_AVP_CHALLENGE_RESP, "CHALLENGE_RESP" },
133 { L2TP_AVP_ASSND_SESS_ID, "ASSND_SESS_ID" },
134 { L2TP_AVP_CALL_SER_NUM, "CALL_SER_NUM" },
135 { L2TP_AVP_MINIMUM_BPS, "MINIMUM_BPS" },
136 { L2TP_AVP_MAXIMUM_BPS, "MAXIMUM_BPS" },
137 { L2TP_AVP_BEARER_TYPE, "BEARER_TYPE" },
138 { L2TP_AVP_FRAMING_TYPE, "FRAMING_TYPE" },
139 { L2TP_AVP_PACKET_PROC_DELAY, "PACKET_PROC_DELAY" },
140 { L2TP_AVP_CALLED_NUMBER, "CALLED_NUMBER" },
141 { L2TP_AVP_CALLING_NUMBER, "CALLING_NUMBER" },
142 { L2TP_AVP_SUB_ADDRESS, "SUB_ADDRESS" },
143 { L2TP_AVP_TX_CONN_SPEED, "TX_CONN_SPEED" },
144 { L2TP_AVP_PHY_CHANNEL_ID, "PHY_CHANNEL_ID" },
145 { L2TP_AVP_INI_RECV_LCP, "INI_RECV_LCP" },
146 { L2TP_AVP_LAST_SENT_LCP, "LAST_SENT_LCP" },
147 { L2TP_AVP_LAST_RECV_LCP, "LAST_RECV_LCP" },
148 { L2TP_AVP_PROXY_AUTH_TYPE, "PROXY_AUTH_TYPE" },
149 { L2TP_AVP_PROXY_AUTH_NAME, "PROXY_AUTH_NAME" },
150 { L2TP_AVP_PROXY_AUTH_CHAL, "PROXY_AUTH_CHAL" },
151 { L2TP_AVP_PROXY_AUTH_ID, "PROXY_AUTH_ID" },
152 { L2TP_AVP_PROXY_AUTH_RESP, "PROXY_AUTH_RESP" },
153 { L2TP_AVP_CALL_ERRORS, "CALL_ERRORS" },
154 { L2TP_AVP_ACCM, "ACCM" },
155 { L2TP_AVP_RANDOM_VECTOR, "RANDOM_VECTOR" },
156 { L2TP_AVP_PRIVATE_GRP_ID, "PRIVATE_GRP_ID" },
157 { L2TP_AVP_RX_CONN_SPEED, "RX_CONN_SPEED" },
158 { L2TP_AVP_SEQ_REQUIRED, "SEQ_REQUIRED" },
159 { L2TP_AVP_PPP_DISCON_CC, "PPP_DISCON_CC" },
160 { 0, NULL }
161 };
162
163 static const struct tok l2tp_authentype2str[] = {
164 { L2TP_AUTHEN_TYPE_RESERVED, "Reserved" },
165 { L2TP_AUTHEN_TYPE_TEXTUAL, "Textual" },
166 { L2TP_AUTHEN_TYPE_CHAP, "CHAP" },
167 { L2TP_AUTHEN_TYPE_PAP, "PAP" },
168 { L2TP_AUTHEN_TYPE_NO_AUTH, "No Auth" },
169 { L2TP_AUTHEN_TYPE_MSCHAPv1, "MS-CHAPv1" },
170 { 0, NULL }
171 };
172
173 #define L2TP_PPP_DISCON_CC_DIRECTION_GLOBAL 0
174 #define L2TP_PPP_DISCON_CC_DIRECTION_AT_PEER 1
175 #define L2TP_PPP_DISCON_CC_DIRECTION_AT_LOCAL 2
176
177 static const struct tok l2tp_cc_direction2str[] = {
178 { L2TP_PPP_DISCON_CC_DIRECTION_GLOBAL, "global error" },
179 { L2TP_PPP_DISCON_CC_DIRECTION_AT_PEER, "at peer" },
180 { L2TP_PPP_DISCON_CC_DIRECTION_AT_LOCAL,"at local" },
181 { 0, NULL }
182 };
183
184 #if 0
185 static char *l2tp_result_code_StopCCN[] = {
186 "Reserved",
187 "General request to clear control connection",
188 "General error--Error Code indicates the problem",
189 "Control channel already exists",
190 "Requester is not authorized to establish a control channel",
191 "The protocol version of the requester is not supported",
192 "Requester is being shut down",
193 "Finite State Machine error"
194 #define L2TP_MAX_RESULT_CODE_STOPCC_INDEX 8
195 };
196 #endif
197
198 #if 0
199 static char *l2tp_result_code_CDN[] = {
200 "Reserved",
201 "Call disconnected due to loss of carrier",
202 "Call disconnected for the reason indicated in error code",
203 "Call disconnected for administrative reasons",
204 "Call failed due to lack of appropriate facilities being " \
205 "available (temporary condition)",
206 "Call failed due to lack of appropriate facilities being " \
207 "available (permanent condition)",
208 "Invalid destination",
209 "Call failed due to no carrier detected",
210 "Call failed due to detection of a busy signal",
211 "Call failed due to lack of a dial tone",
212 "Call was not established within time allotted by LAC",
213 "Call was connected but no appropriate framing was detected"
214 #define L2TP_MAX_RESULT_CODE_CDN_INDEX 12
215 };
216 #endif
217
218 #if 0
219 static char *l2tp_error_code_general[] = {
220 "No general error",
221 "No control connection exists yet for this LAC-LNS pair",
222 "Length is wrong",
223 "One of the field values was out of range or " \
224 "reserved field was non-zero"
225 "Insufficient resources to handle this operation now",
226 "The Session ID is invalid in this context",
227 "A generic vendor-specific error occurred in the LAC",
228 "Try another"
229 #define L2TP_MAX_ERROR_CODE_GENERAL_INDEX 8
230 };
231 #endif
232
233 /******************************/
234 /* generic print out routines */
235 /******************************/
236 static void
print_string(const u_char * dat,u_int length)237 print_string(const u_char *dat, u_int length)
238 {
239 u_int i;
240 for (i=0; i<length; i++) {
241 printf("%c", *dat++);
242 }
243 }
244
245 static void
print_octets(const u_char * dat,u_int length)246 print_octets(const u_char *dat, u_int length)
247 {
248 u_int i;
249 for (i=0; i<length; i++) {
250 printf("%02x", *dat++);
251 }
252 }
253
254 static void
print_16bits_val(const u_int16_t * dat)255 print_16bits_val(const u_int16_t *dat)
256 {
257 printf("%u", EXTRACT_16BITS(dat));
258 }
259
260 static void
print_32bits_val(const u_int32_t * dat)261 print_32bits_val(const u_int32_t *dat)
262 {
263 printf("%lu", (u_long)EXTRACT_32BITS(dat));
264 }
265
266 /***********************************/
267 /* AVP-specific print out routines */
268 /***********************************/
269 static void
l2tp_msgtype_print(const u_char * dat)270 l2tp_msgtype_print(const u_char *dat)
271 {
272 u_int16_t *ptr = (u_int16_t*)dat;
273
274 printf("%s", tok2str(l2tp_msgtype2str, "MSGTYPE-#%u",
275 EXTRACT_16BITS(ptr)));
276 }
277
278 static void
l2tp_result_code_print(const u_char * dat,u_int length)279 l2tp_result_code_print(const u_char *dat, u_int length)
280 {
281 u_int16_t *ptr = (u_int16_t *)dat;
282
283 printf("%u", EXTRACT_16BITS(ptr)); ptr++; /* Result Code */
284 if (length > 2) { /* Error Code (opt) */
285 printf("/%u", EXTRACT_16BITS(ptr)); ptr++;
286 }
287 if (length > 4) { /* Error Message (opt) */
288 printf(" ");
289 print_string((u_char *)ptr, length - 4);
290 }
291 }
292
293 static void
l2tp_proto_ver_print(const u_int16_t * dat)294 l2tp_proto_ver_print(const u_int16_t *dat)
295 {
296 printf("%u.%u", (EXTRACT_16BITS(dat) >> 8),
297 (EXTRACT_16BITS(dat) & 0xff));
298 }
299
300 static void
l2tp_framing_cap_print(const u_char * dat)301 l2tp_framing_cap_print(const u_char *dat)
302 {
303 u_int32_t *ptr = (u_int32_t *)dat;
304
305 if (EXTRACT_32BITS(ptr) & L2TP_FRAMING_CAP_ASYNC_MASK) {
306 printf("A");
307 }
308 if (EXTRACT_32BITS(ptr) & L2TP_FRAMING_CAP_SYNC_MASK) {
309 printf("S");
310 }
311 }
312
313 static void
l2tp_bearer_cap_print(const u_char * dat)314 l2tp_bearer_cap_print(const u_char *dat)
315 {
316 u_int32_t *ptr = (u_int32_t *)dat;
317
318 if (EXTRACT_32BITS(ptr) & L2TP_BEARER_CAP_ANALOG_MASK) {
319 printf("A");
320 }
321 if (EXTRACT_32BITS(ptr) & L2TP_BEARER_CAP_DIGITAL_MASK) {
322 printf("D");
323 }
324 }
325
326 static void
l2tp_q931_cc_print(const u_char * dat,u_int length)327 l2tp_q931_cc_print(const u_char *dat, u_int length)
328 {
329 print_16bits_val((u_int16_t *)dat);
330 printf(", %02x", dat[2]);
331 if (length > 3) {
332 printf(" ");
333 print_string(dat+3, length-3);
334 }
335 }
336
337 static void
l2tp_bearer_type_print(const u_char * dat)338 l2tp_bearer_type_print(const u_char *dat)
339 {
340 u_int32_t *ptr = (u_int32_t *)dat;
341
342 if (EXTRACT_32BITS(ptr) & L2TP_BEARER_TYPE_ANALOG_MASK) {
343 printf("A");
344 }
345 if (EXTRACT_32BITS(ptr) & L2TP_BEARER_TYPE_DIGITAL_MASK) {
346 printf("D");
347 }
348 }
349
350 static void
l2tp_framing_type_print(const u_char * dat)351 l2tp_framing_type_print(const u_char *dat)
352 {
353 u_int32_t *ptr = (u_int32_t *)dat;
354
355 if (EXTRACT_32BITS(ptr) & L2TP_FRAMING_TYPE_ASYNC_MASK) {
356 printf("A");
357 }
358 if (EXTRACT_32BITS(ptr) & L2TP_FRAMING_TYPE_SYNC_MASK) {
359 printf("S");
360 }
361 }
362
363 static void
l2tp_packet_proc_delay_print(void)364 l2tp_packet_proc_delay_print(void)
365 {
366 printf("obsolete");
367 }
368
369 static void
l2tp_proxy_auth_type_print(const u_char * dat)370 l2tp_proxy_auth_type_print(const u_char *dat)
371 {
372 u_int16_t *ptr = (u_int16_t *)dat;
373
374 printf("%s", tok2str(l2tp_authentype2str,
375 "AuthType-#%u", EXTRACT_16BITS(ptr)));
376 }
377
378 static void
l2tp_proxy_auth_id_print(const u_char * dat)379 l2tp_proxy_auth_id_print(const u_char *dat)
380 {
381 u_int16_t *ptr = (u_int16_t *)dat;
382
383 printf("%u", EXTRACT_16BITS(ptr) & L2TP_PROXY_AUTH_ID_MASK);
384 }
385
386 static void
l2tp_call_errors_print(const u_char * dat)387 l2tp_call_errors_print(const u_char *dat)
388 {
389 u_int16_t *ptr = (u_int16_t *)dat;
390 u_int16_t val_h, val_l;
391
392 ptr++; /* skip "Reserved" */
393
394 val_h = EXTRACT_16BITS(ptr); ptr++;
395 val_l = EXTRACT_16BITS(ptr); ptr++;
396 printf("CRCErr=%u ", (val_h<<16) + val_l);
397
398 val_h = EXTRACT_16BITS(ptr); ptr++;
399 val_l = EXTRACT_16BITS(ptr); ptr++;
400 printf("FrameErr=%u ", (val_h<<16) + val_l);
401
402 val_h = EXTRACT_16BITS(ptr); ptr++;
403 val_l = EXTRACT_16BITS(ptr); ptr++;
404 printf("HardOver=%u ", (val_h<<16) + val_l);
405
406 val_h = EXTRACT_16BITS(ptr); ptr++;
407 val_l = EXTRACT_16BITS(ptr); ptr++;
408 printf("BufOver=%u ", (val_h<<16) + val_l);
409
410 val_h = EXTRACT_16BITS(ptr); ptr++;
411 val_l = EXTRACT_16BITS(ptr); ptr++;
412 printf("Timeout=%u ", (val_h<<16) + val_l);
413
414 val_h = EXTRACT_16BITS(ptr); ptr++;
415 val_l = EXTRACT_16BITS(ptr); ptr++;
416 printf("AlignErr=%u ", (val_h<<16) + val_l);
417 }
418
419 static void
l2tp_accm_print(const u_char * dat)420 l2tp_accm_print(const u_char *dat)
421 {
422 u_int16_t *ptr = (u_int16_t *)dat;
423 u_int16_t val_h, val_l;
424
425 ptr++; /* skip "Reserved" */
426
427 val_h = EXTRACT_16BITS(ptr); ptr++;
428 val_l = EXTRACT_16BITS(ptr); ptr++;
429 printf("send=%08x ", (val_h<<16) + val_l);
430
431 val_h = EXTRACT_16BITS(ptr); ptr++;
432 val_l = EXTRACT_16BITS(ptr); ptr++;
433 printf("recv=%08x ", (val_h<<16) + val_l);
434 }
435
436 static void
l2tp_ppp_discon_cc_print(const u_char * dat,u_int length)437 l2tp_ppp_discon_cc_print(const u_char *dat, u_int length)
438 {
439 u_int16_t *ptr = (u_int16_t *)dat;
440
441 printf("%04x, ", EXTRACT_16BITS(ptr)); ptr++; /* Disconnect Code */
442 printf("%04x ", EXTRACT_16BITS(ptr)); ptr++; /* Control Protocol Number */
443 printf("%s", tok2str(l2tp_cc_direction2str,
444 "Direction-#%u", *((u_char *)ptr++)));
445
446 if (length > 5) {
447 printf(" ");
448 print_string((const u_char *)ptr, length-5);
449 }
450 }
451
452 static void
l2tp_avp_print(const u_char * dat,int length)453 l2tp_avp_print(const u_char *dat, int length)
454 {
455 u_int len;
456 const u_int16_t *ptr = (u_int16_t *)dat;
457 u_int16_t attr_type;
458 int hidden = FALSE;
459
460 if (length <= 0) {
461 return;
462 }
463
464 printf(" ");
465
466 TCHECK(*ptr); /* Flags & Length */
467 len = EXTRACT_16BITS(ptr) & L2TP_AVP_HDR_LEN_MASK;
468
469 /* If it is not long enough to contain the header, we'll give up. */
470 if (len < 6)
471 goto trunc;
472
473 /* If it goes past the end of the remaining length of the packet,
474 we'll give up. */
475 if (len > (u_int)length)
476 goto trunc;
477
478 /* If it goes past the end of the remaining length of the captured
479 data, we'll give up. */
480 TCHECK2(*ptr, len);
481 /* After this point, no need to worry about truncation */
482
483 if (EXTRACT_16BITS(ptr) & L2TP_AVP_HDR_FLAG_MANDATORY) {
484 printf("*");
485 }
486 if (EXTRACT_16BITS(ptr) & L2TP_AVP_HDR_FLAG_HIDDEN) {
487 hidden = TRUE;
488 printf("?");
489 }
490 ptr++;
491
492 if (EXTRACT_16BITS(ptr)) {
493 /* Vendor Specific Attribute */
494 printf("VENDOR%04x:", EXTRACT_16BITS(ptr)); ptr++;
495 printf("ATTR%04x", EXTRACT_16BITS(ptr)); ptr++;
496 printf("(");
497 print_octets((u_char *)ptr, len-6);
498 printf(")");
499 } else {
500 /* IETF-defined Attributes */
501 ptr++;
502 attr_type = EXTRACT_16BITS(ptr); ptr++;
503 printf("%s", tok2str(l2tp_avp2str, "AVP-#%u", attr_type));
504 printf("(");
505 if (hidden) {
506 printf("???");
507 } else {
508 switch (attr_type) {
509 case L2TP_AVP_MSGTYPE:
510 l2tp_msgtype_print((u_char *)ptr);
511 break;
512 case L2TP_AVP_RESULT_CODE:
513 l2tp_result_code_print((u_char *)ptr, len-6);
514 break;
515 case L2TP_AVP_PROTO_VER:
516 l2tp_proto_ver_print(ptr);
517 break;
518 case L2TP_AVP_FRAMING_CAP:
519 l2tp_framing_cap_print((u_char *)ptr);
520 break;
521 case L2TP_AVP_BEARER_CAP:
522 l2tp_bearer_cap_print((u_char *)ptr);
523 break;
524 case L2TP_AVP_TIE_BREAKER:
525 print_octets((u_char *)ptr, 8);
526 break;
527 case L2TP_AVP_FIRM_VER:
528 case L2TP_AVP_ASSND_TUN_ID:
529 case L2TP_AVP_RECV_WIN_SIZE:
530 case L2TP_AVP_ASSND_SESS_ID:
531 print_16bits_val(ptr);
532 break;
533 case L2TP_AVP_HOST_NAME:
534 case L2TP_AVP_VENDOR_NAME:
535 case L2TP_AVP_CALLING_NUMBER:
536 case L2TP_AVP_CALLED_NUMBER:
537 case L2TP_AVP_SUB_ADDRESS:
538 case L2TP_AVP_PROXY_AUTH_NAME:
539 case L2TP_AVP_PRIVATE_GRP_ID:
540 print_string((u_char *)ptr, len-6);
541 break;
542 case L2TP_AVP_CHALLENGE:
543 case L2TP_AVP_INI_RECV_LCP:
544 case L2TP_AVP_LAST_SENT_LCP:
545 case L2TP_AVP_LAST_RECV_LCP:
546 case L2TP_AVP_PROXY_AUTH_CHAL:
547 case L2TP_AVP_PROXY_AUTH_RESP:
548 case L2TP_AVP_RANDOM_VECTOR:
549 print_octets((u_char *)ptr, len-6);
550 break;
551 case L2TP_AVP_Q931_CC:
552 l2tp_q931_cc_print((u_char *)ptr, len-6);
553 break;
554 case L2TP_AVP_CHALLENGE_RESP:
555 print_octets((u_char *)ptr, 16);
556 break;
557 case L2TP_AVP_CALL_SER_NUM:
558 case L2TP_AVP_MINIMUM_BPS:
559 case L2TP_AVP_MAXIMUM_BPS:
560 case L2TP_AVP_TX_CONN_SPEED:
561 case L2TP_AVP_PHY_CHANNEL_ID:
562 case L2TP_AVP_RX_CONN_SPEED:
563 print_32bits_val((u_int32_t *)ptr);
564 break;
565 case L2TP_AVP_BEARER_TYPE:
566 l2tp_bearer_type_print((u_char *)ptr);
567 break;
568 case L2TP_AVP_FRAMING_TYPE:
569 l2tp_framing_type_print((u_char *)ptr);
570 break;
571 case L2TP_AVP_PACKET_PROC_DELAY:
572 l2tp_packet_proc_delay_print();
573 break;
574 case L2TP_AVP_PROXY_AUTH_TYPE:
575 l2tp_proxy_auth_type_print((u_char *)ptr);
576 break;
577 case L2TP_AVP_PROXY_AUTH_ID:
578 l2tp_proxy_auth_id_print((u_char *)ptr);
579 break;
580 case L2TP_AVP_CALL_ERRORS:
581 l2tp_call_errors_print((u_char *)ptr);
582 break;
583 case L2TP_AVP_ACCM:
584 l2tp_accm_print((u_char *)ptr);
585 break;
586 case L2TP_AVP_SEQ_REQUIRED:
587 break; /* No Attribute Value */
588 case L2TP_AVP_PPP_DISCON_CC:
589 l2tp_ppp_discon_cc_print((u_char *)ptr, len-6);
590 break;
591 default:
592 break;
593 }
594 }
595 printf(")");
596 }
597
598 l2tp_avp_print(dat+len, length-len);
599 return;
600
601 trunc:
602 printf("|...");
603 }
604
605
606 void
l2tp_print(const u_char * dat,u_int length)607 l2tp_print(const u_char *dat, u_int length)
608 {
609 const u_char *ptr = dat;
610 u_int cnt = 0; /* total octets consumed */
611 u_int16_t pad;
612 int flag_t, flag_l, flag_s, flag_o;
613 u_int16_t l2tp_len;
614
615 flag_t = flag_l = flag_s = flag_o = FALSE;
616
617 TCHECK2(*ptr, 2); /* Flags & Version */
618 if ((EXTRACT_16BITS(ptr) & L2TP_VERSION_MASK) == L2TP_VERSION_L2TP) {
619 printf(" l2tp:");
620 } else if ((EXTRACT_16BITS(ptr) & L2TP_VERSION_MASK) == L2TP_VERSION_L2F) {
621 printf(" l2f:");
622 return; /* nothing to do */
623 } else {
624 printf(" Unknown Version, neither L2F(1) nor L2TP(2)");
625 return; /* nothing we can do */
626 }
627
628 printf("[");
629 if (EXTRACT_16BITS(ptr) & L2TP_FLAG_TYPE) {
630 flag_t = TRUE;
631 printf("T");
632 }
633 if (EXTRACT_16BITS(ptr) & L2TP_FLAG_LENGTH) {
634 flag_l = TRUE;
635 printf("L");
636 }
637 if (EXTRACT_16BITS(ptr) & L2TP_FLAG_SEQUENCE) {
638 flag_s = TRUE;
639 printf("S");
640 }
641 if (EXTRACT_16BITS(ptr) & L2TP_FLAG_OFFSET) {
642 flag_o = TRUE;
643 printf("O");
644 }
645 if (EXTRACT_16BITS(ptr) & L2TP_FLAG_PRIORITY)
646 printf("P");
647 printf("]");
648
649 ptr += 2;
650 cnt += 2;
651
652 if (flag_l) {
653 TCHECK2(*ptr, 2); /* Length */
654 l2tp_len = EXTRACT_16BITS(ptr);
655 ptr += 2;
656 cnt += 2;
657 } else {
658 l2tp_len = 0;
659 }
660
661 TCHECK2(*ptr, 2); /* Tunnel ID */
662 printf("(%u/", EXTRACT_16BITS(ptr));
663 ptr += 2;
664 cnt += 2;
665 TCHECK2(*ptr, 2); /* Session ID */
666 printf("%u)", EXTRACT_16BITS(ptr));
667 ptr += 2;
668 cnt += 2;
669
670 if (flag_s) {
671 TCHECK2(*ptr, 2); /* Ns */
672 printf("Ns=%u,", EXTRACT_16BITS(ptr));
673 ptr += 2;
674 cnt += 2;
675 TCHECK2(*ptr, 2); /* Nr */
676 printf("Nr=%u", EXTRACT_16BITS(ptr));
677 ptr += 2;
678 cnt += 2;
679 }
680
681 if (flag_o) {
682 TCHECK2(*ptr, 2); /* Offset Size */
683 pad = EXTRACT_16BITS(ptr);
684 ptr += (2 + pad);
685 cnt += (2 + pad);
686 }
687
688 if (flag_l) {
689 if (length < l2tp_len) {
690 printf(" Length %u larger than packet", l2tp_len);
691 return;
692 }
693 length = l2tp_len;
694 }
695 if (length < cnt) {
696 printf(" Length %u smaller than header length", length);
697 return;
698 }
699 if (flag_t) {
700 if (!flag_l) {
701 printf(" No length");
702 return;
703 }
704 if (length - cnt == 0) {
705 printf(" ZLB");
706 } else {
707 l2tp_avp_print(ptr, length - cnt);
708 }
709 } else {
710 printf(" {");
711 ppp_print(ptr, length - cnt);
712 printf("}");
713 }
714
715 return;
716
717 trunc:
718 printf("%s", tstr);
719 }
720