xref: /freebsd/contrib/tcpdump/print-ppp.c (revision 02e9120893770924227138ba49df1edb3896112a)
1 /*
2  * Copyright (c) 1990, 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  * Extensively modified by Motonori Shindo (mshindo@mshindo.net) for more
22  * complete PPP support.
23  */
24 
25 /* \summary: Point to Point Protocol (PPP) printer */
26 
27 /*
28  * TODO:
29  * o resolve XXX as much as possible
30  * o MP support
31  * o BAP support
32  */
33 
34 #ifdef HAVE_CONFIG_H
35 #include <config.h>
36 #endif
37 
38 #include "netdissect-stdinc.h"
39 
40 #ifdef __bsdi__
41 #include <net/slcompress.h>
42 #include <net/if_ppp.h>
43 #endif
44 
45 #include "netdissect.h"
46 #include "extract.h"
47 #include "addrtoname.h"
48 #include "ppp.h"
49 #include "chdlc.h"
50 #include "ethertype.h"
51 #include "oui.h"
52 #include "netdissect-alloc.h"
53 
54 /*
55  * The following constants are defined by IANA. Please refer to
56  *    https://www.isi.edu/in-notes/iana/assignments/ppp-numbers
57  * for the up-to-date information.
58  */
59 
60 /* Protocol Codes defined in ppp.h */
61 
62 static const struct tok ppptype2str[] = {
63         { PPP_IP,	  "IP" },
64         { PPP_OSI,	  "OSI" },
65         { PPP_NS,	  "NS" },
66         { PPP_DECNET,	  "DECNET" },
67         { PPP_APPLE,	  "APPLE" },
68 	{ PPP_IPX,	  "IPX" },
69 	{ PPP_VJC,	  "VJC IP" },
70 	{ PPP_VJNC,	  "VJNC IP" },
71 	{ PPP_BRPDU,	  "BRPDU" },
72 	{ PPP_STII,	  "STII" },
73 	{ PPP_VINES,	  "VINES" },
74 	{ PPP_MPLS_UCAST, "MPLS" },
75 	{ PPP_MPLS_MCAST, "MPLS" },
76         { PPP_COMP,       "Compressed"},
77         { PPP_ML,         "MLPPP"},
78         { PPP_IPV6,       "IP6"},
79 
80 	{ PPP_HELLO,	  "HELLO" },
81 	{ PPP_LUXCOM,	  "LUXCOM" },
82 	{ PPP_SNS,	  "SNS" },
83 	{ PPP_IPCP,	  "IPCP" },
84 	{ PPP_OSICP,	  "OSICP" },
85 	{ PPP_NSCP,	  "NSCP" },
86 	{ PPP_DECNETCP,   "DECNETCP" },
87 	{ PPP_APPLECP,	  "APPLECP" },
88 	{ PPP_IPXCP,	  "IPXCP" },
89 	{ PPP_STIICP,	  "STIICP" },
90 	{ PPP_VINESCP,	  "VINESCP" },
91         { PPP_IPV6CP,     "IP6CP" },
92 	{ PPP_MPLSCP,	  "MPLSCP" },
93 
94 	{ PPP_LCP,	  "LCP" },
95 	{ PPP_PAP,	  "PAP" },
96 	{ PPP_LQM,	  "LQM" },
97 	{ PPP_CHAP,	  "CHAP" },
98 	{ PPP_EAP,	  "EAP" },
99 	{ PPP_SPAP,	  "SPAP" },
100 	{ PPP_SPAP_OLD,	  "Old-SPAP" },
101 	{ PPP_BACP,	  "BACP" },
102 	{ PPP_BAP,	  "BAP" },
103 	{ PPP_MPCP,	  "MLPPP-CP" },
104 	{ PPP_CCP,	  "CCP" },
105 	{ 0,		  NULL }
106 };
107 
108 /* Control Protocols (LCP/IPCP/CCP etc.) Codes defined in RFC 1661 */
109 
110 #define CPCODES_VEXT		0	/* Vendor-Specific (RFC2153) */
111 #define CPCODES_CONF_REQ	1	/* Configure-Request */
112 #define CPCODES_CONF_ACK	2	/* Configure-Ack */
113 #define CPCODES_CONF_NAK	3	/* Configure-Nak */
114 #define CPCODES_CONF_REJ	4	/* Configure-Reject */
115 #define CPCODES_TERM_REQ	5	/* Terminate-Request */
116 #define CPCODES_TERM_ACK	6	/* Terminate-Ack */
117 #define CPCODES_CODE_REJ	7	/* Code-Reject */
118 #define CPCODES_PROT_REJ	8	/* Protocol-Reject (LCP only) */
119 #define CPCODES_ECHO_REQ	9	/* Echo-Request (LCP only) */
120 #define CPCODES_ECHO_RPL	10	/* Echo-Reply (LCP only) */
121 #define CPCODES_DISC_REQ	11	/* Discard-Request (LCP only) */
122 #define CPCODES_ID		12	/* Identification (LCP only) RFC1570 */
123 #define CPCODES_TIME_REM	13	/* Time-Remaining (LCP only) RFC1570 */
124 #define CPCODES_RESET_REQ	14	/* Reset-Request (CCP only) RFC1962 */
125 #define CPCODES_RESET_REP	15	/* Reset-Reply (CCP only) */
126 
127 static const struct tok cpcodes[] = {
128 	{CPCODES_VEXT,      "Vendor-Extension"}, /* RFC2153 */
129 	{CPCODES_CONF_REQ,  "Conf-Request"},
130         {CPCODES_CONF_ACK,  "Conf-Ack"},
131 	{CPCODES_CONF_NAK,  "Conf-Nack"},
132 	{CPCODES_CONF_REJ,  "Conf-Reject"},
133 	{CPCODES_TERM_REQ,  "Term-Request"},
134 	{CPCODES_TERM_ACK,  "Term-Ack"},
135 	{CPCODES_CODE_REJ,  "Code-Reject"},
136 	{CPCODES_PROT_REJ,  "Prot-Reject"},
137 	{CPCODES_ECHO_REQ,  "Echo-Request"},
138 	{CPCODES_ECHO_RPL,  "Echo-Reply"},
139 	{CPCODES_DISC_REQ,  "Disc-Req"},
140 	{CPCODES_ID,        "Ident"},            /* RFC1570 */
141 	{CPCODES_TIME_REM,  "Time-Rem"},         /* RFC1570 */
142 	{CPCODES_RESET_REQ, "Reset-Req"},        /* RFC1962 */
143 	{CPCODES_RESET_REP, "Reset-Ack"},        /* RFC1962 */
144         {0,                 NULL}
145 };
146 
147 /* LCP Config Options */
148 
149 #define LCPOPT_VEXT	0
150 #define LCPOPT_MRU	1
151 #define LCPOPT_ACCM	2
152 #define LCPOPT_AP	3
153 #define LCPOPT_QP	4
154 #define LCPOPT_MN	5
155 #define LCPOPT_DEP6	6
156 #define LCPOPT_PFC	7
157 #define LCPOPT_ACFC	8
158 #define LCPOPT_FCSALT	9
159 #define LCPOPT_SDP	10
160 #define LCPOPT_NUMMODE	11
161 #define LCPOPT_DEP12	12
162 #define LCPOPT_CBACK	13
163 #define LCPOPT_DEP14	14
164 #define LCPOPT_DEP15	15
165 #define LCPOPT_DEP16	16
166 #define LCPOPT_MLMRRU	17
167 #define LCPOPT_MLSSNHF	18
168 #define LCPOPT_MLED	19
169 #define LCPOPT_PROP	20
170 #define LCPOPT_DCEID	21
171 #define LCPOPT_MPP	22
172 #define LCPOPT_LD	23
173 #define LCPOPT_LCPAOPT	24
174 #define LCPOPT_COBS	25
175 #define LCPOPT_PE	26
176 #define LCPOPT_MLHF	27
177 #define LCPOPT_I18N	28
178 #define LCPOPT_SDLOS	29
179 #define LCPOPT_PPPMUX	30
180 
181 static const char *lcpconfopts[] = {
182 	"Vend-Ext",		/* (0) */
183 	"MRU",			/* (1) */
184 	"ACCM",			/* (2) */
185 	"Auth-Prot",		/* (3) */
186 	"Qual-Prot",		/* (4) */
187 	"Magic-Num",		/* (5) */
188 	"deprecated(6)",	/* used to be a Quality Protocol */
189 	"PFC",			/* (7) */
190 	"ACFC",			/* (8) */
191 	"FCS-Alt",		/* (9) */
192 	"SDP",			/* (10) */
193 	"Num-Mode",		/* (11) */
194 	"deprecated(12)",	/* used to be a Multi-Link-Procedure*/
195 	"Call-Back",		/* (13) */
196 	"deprecated(14)",	/* used to be a Connect-Time */
197 	"deprecated(15)",	/* used to be a Compund-Frames */
198 	"deprecated(16)",	/* used to be a Nominal-Data-Encap */
199 	"MRRU",			/* (17) */
200 	"12-Bit seq #",		/* (18) */
201 	"End-Disc",		/* (19) */
202 	"Proprietary",		/* (20) */
203 	"DCE-Id",		/* (21) */
204 	"MP+",			/* (22) */
205 	"Link-Disc",		/* (23) */
206 	"LCP-Auth-Opt",		/* (24) */
207 	"COBS",			/* (25) */
208 	"Prefix-elision",	/* (26) */
209 	"Multilink-header-Form",/* (27) */
210 	"I18N",			/* (28) */
211 	"SDL-over-SONET/SDH",	/* (29) */
212 	"PPP-Muxing",		/* (30) */
213 };
214 
215 #define NUM_LCPOPTS	(sizeof(lcpconfopts) / sizeof(lcpconfopts[0]))
216 
217 /* ECP - to be supported */
218 
219 /* CCP Config Options */
220 
221 #define CCPOPT_OUI	0	/* RFC1962 */
222 #define CCPOPT_PRED1	1	/* RFC1962 */
223 #define CCPOPT_PRED2	2	/* RFC1962 */
224 #define CCPOPT_PJUMP	3	/* RFC1962 */
225 /* 4-15 unassigned */
226 #define CCPOPT_HPPPC	16	/* RFC1962 */
227 #define CCPOPT_STACLZS	17	/* RFC1974 */
228 #define CCPOPT_MPPC	18	/* RFC2118 */
229 #define CCPOPT_GFZA	19	/* RFC1962 */
230 #define CCPOPT_V42BIS	20	/* RFC1962 */
231 #define CCPOPT_BSDCOMP	21	/* RFC1977 */
232 /* 22 unassigned */
233 #define CCPOPT_LZSDCP	23	/* RFC1967 */
234 #define CCPOPT_MVRCA	24	/* RFC1975 */
235 #define CCPOPT_DEC	25	/* RFC1976 */
236 #define CCPOPT_DEFLATE	26	/* RFC1979 */
237 /* 27-254 unassigned */
238 #define CCPOPT_RESV	255	/* RFC1962 */
239 
240 static const struct tok ccpconfopts_values[] = {
241         { CCPOPT_OUI, "OUI" },
242         { CCPOPT_PRED1, "Pred-1" },
243         { CCPOPT_PRED2, "Pred-2" },
244         { CCPOPT_PJUMP, "Puddle" },
245         { CCPOPT_HPPPC, "HP-PPC" },
246         { CCPOPT_STACLZS, "Stac-LZS" },
247         { CCPOPT_MPPC, "MPPC" },
248         { CCPOPT_GFZA, "Gand-FZA" },
249         { CCPOPT_V42BIS, "V.42bis" },
250         { CCPOPT_BSDCOMP, "BSD-Comp" },
251         { CCPOPT_LZSDCP, "LZS-DCP" },
252         { CCPOPT_MVRCA, "MVRCA" },
253         { CCPOPT_DEC, "DEC" },
254         { CCPOPT_DEFLATE, "Deflate" },
255         { CCPOPT_RESV, "Reserved"},
256         {0,                 NULL}
257 };
258 
259 /* BACP Config Options */
260 
261 #define BACPOPT_FPEER	1	/* RFC2125 */
262 
263 static const struct tok bacconfopts_values[] = {
264         { BACPOPT_FPEER, "Favored-Peer" },
265         {0,                 NULL}
266 };
267 
268 
269 /* SDCP - to be supported */
270 
271 /* IPCP Config Options */
272 #define IPCPOPT_2ADDR	1	/* RFC1172, RFC1332 (deprecated) */
273 #define IPCPOPT_IPCOMP	2	/* RFC1332 */
274 #define IPCPOPT_ADDR	3	/* RFC1332 */
275 #define IPCPOPT_MOBILE4	4	/* RFC2290 */
276 #define IPCPOPT_PRIDNS	129	/* RFC1877 */
277 #define IPCPOPT_PRINBNS	130	/* RFC1877 */
278 #define IPCPOPT_SECDNS	131	/* RFC1877 */
279 #define IPCPOPT_SECNBNS	132	/* RFC1877 */
280 
281 static const struct tok ipcpopt_values[] = {
282         { IPCPOPT_2ADDR, "IP-Addrs" },
283         { IPCPOPT_IPCOMP, "IP-Comp" },
284         { IPCPOPT_ADDR, "IP-Addr" },
285         { IPCPOPT_MOBILE4, "Home-Addr" },
286         { IPCPOPT_PRIDNS, "Pri-DNS" },
287         { IPCPOPT_PRINBNS, "Pri-NBNS" },
288         { IPCPOPT_SECDNS, "Sec-DNS" },
289         { IPCPOPT_SECNBNS, "Sec-NBNS" },
290 	{ 0,		  NULL }
291 };
292 
293 #define IPCPOPT_IPCOMP_HDRCOMP 0x61  /* rfc3544 */
294 #define IPCPOPT_IPCOMP_MINLEN    14
295 
296 static const struct tok ipcpopt_compproto_values[] = {
297         { PPP_VJC, "VJ-Comp" },
298         { IPCPOPT_IPCOMP_HDRCOMP, "IP Header Compression" },
299 	{ 0,		  NULL }
300 };
301 
302 static const struct tok ipcpopt_compproto_subopt_values[] = {
303         { 1, "RTP-Compression" },
304         { 2, "Enhanced RTP-Compression" },
305 	{ 0,		  NULL }
306 };
307 
308 /* IP6CP Config Options */
309 #define IP6CP_IFID      1
310 
311 static const struct tok ip6cpopt_values[] = {
312         { IP6CP_IFID, "Interface-ID" },
313 	{ 0,		  NULL }
314 };
315 
316 /* ATCP - to be supported */
317 /* OSINLCP - to be supported */
318 /* BVCP - to be supported */
319 /* BCP - to be supported */
320 /* IPXCP - to be supported */
321 /* MPLSCP - to be supported */
322 
323 /* Auth Algorithms */
324 
325 /* 0-4 Reserved (RFC1994) */
326 #define AUTHALG_CHAPMD5	5	/* RFC1994 */
327 #define AUTHALG_MSCHAP1	128	/* RFC2433 */
328 #define AUTHALG_MSCHAP2	129	/* RFC2795 */
329 
330 static const struct tok authalg_values[] = {
331         { AUTHALG_CHAPMD5, "MD5" },
332         { AUTHALG_MSCHAP1, "MS-CHAPv1" },
333         { AUTHALG_MSCHAP2, "MS-CHAPv2" },
334 	{ 0,		  NULL }
335 };
336 
337 /* FCS Alternatives - to be supported */
338 
339 /* Multilink Endpoint Discriminator (RFC1717) */
340 #define MEDCLASS_NULL	0	/* Null Class */
341 #define MEDCLASS_LOCAL	1	/* Locally Assigned */
342 #define MEDCLASS_IPV4	2	/* Internet Protocol (IPv4) */
343 #define MEDCLASS_MAC	3	/* IEEE 802.1 global MAC address */
344 #define MEDCLASS_MNB	4	/* PPP Magic Number Block */
345 #define MEDCLASS_PSNDN	5	/* Public Switched Network Director Number */
346 
347 /* PPP LCP Callback */
348 #define CALLBACK_AUTH	0	/* Location determined by user auth */
349 #define CALLBACK_DSTR	1	/* Dialing string */
350 #define CALLBACK_LID	2	/* Location identifier */
351 #define CALLBACK_E164	3	/* E.164 number */
352 #define CALLBACK_X500	4	/* X.500 distinguished name */
353 #define CALLBACK_CBCP	6	/* Location is determined during CBCP nego */
354 
355 static const struct tok ppp_callback_values[] = {
356         { CALLBACK_AUTH, "UserAuth" },
357         { CALLBACK_DSTR, "DialString" },
358         { CALLBACK_LID, "LocalID" },
359         { CALLBACK_E164, "E.164" },
360         { CALLBACK_X500, "X.500" },
361         { CALLBACK_CBCP, "CBCP" },
362 	{ 0,		  NULL }
363 };
364 
365 /* CHAP */
366 
367 #define CHAP_CHAL	1
368 #define CHAP_RESP	2
369 #define CHAP_SUCC	3
370 #define CHAP_FAIL	4
371 
372 static const struct tok chapcode_values[] = {
373 	{ CHAP_CHAL, "Challenge" },
374 	{ CHAP_RESP, "Response" },
375 	{ CHAP_SUCC, "Success" },
376 	{ CHAP_FAIL, "Fail" },
377         { 0, NULL}
378 };
379 
380 /* PAP */
381 
382 #define PAP_AREQ	1
383 #define PAP_AACK	2
384 #define PAP_ANAK	3
385 
386 static const struct tok papcode_values[] = {
387         { PAP_AREQ, "Auth-Req" },
388         { PAP_AACK, "Auth-ACK" },
389         { PAP_ANAK, "Auth-NACK" },
390         { 0, NULL }
391 };
392 
393 /* BAP */
394 #define BAP_CALLREQ	1
395 #define BAP_CALLRES	2
396 #define BAP_CBREQ	3
397 #define BAP_CBRES	4
398 #define BAP_LDQREQ	5
399 #define BAP_LDQRES	6
400 #define BAP_CSIND	7
401 #define BAP_CSRES	8
402 
403 static u_int print_lcp_config_options(netdissect_options *, const u_char *p, u_int);
404 static u_int print_ipcp_config_options(netdissect_options *, const u_char *p, u_int);
405 static u_int print_ip6cp_config_options(netdissect_options *, const u_char *p, u_int);
406 static u_int print_ccp_config_options(netdissect_options *, const u_char *p, u_int);
407 static u_int print_bacp_config_options(netdissect_options *, const u_char *p, u_int);
408 static void handle_ppp(netdissect_options *, u_int proto, const u_char *p, u_int length);
409 
410 /* generic Control Protocol (e.g. LCP, IPCP, CCP, etc.) handler */
411 static void
412 handle_ctrl_proto(netdissect_options *ndo,
413                   u_int proto, const u_char *pptr, u_int length)
414 {
415 	const char *typestr;
416 	u_int code, len;
417 	u_int (*pfunc)(netdissect_options *, const u_char *, u_int);
418 	u_int tlen, advance;
419         const u_char *tptr;
420 
421         tptr=pptr;
422 
423         typestr = tok2str(ppptype2str, "unknown ctrl-proto (0x%04x)", proto);
424 	ND_PRINT("%s, ", typestr);
425 
426 	if (length < 4) /* FIXME weak boundary checking */
427 		goto trunc;
428 	ND_TCHECK_2(tptr);
429 
430 	code = GET_U_1(tptr);
431 	tptr++;
432 
433 	ND_PRINT("%s (0x%02x), id %u, length %u",
434 	          tok2str(cpcodes, "Unknown Opcode",code),
435 	          code,
436 	          GET_U_1(tptr), /* ID */
437 	          length + 2);
438 	tptr++;
439 
440 	if (!ndo->ndo_vflag)
441 		return;
442 
443 	len = GET_BE_U_2(tptr);
444 	tptr += 2;
445 
446 	if (len < 4) {
447 		ND_PRINT("\n\tencoded length %u (< 4))", len);
448 		return;
449 	}
450 
451 	if (len > length) {
452 		ND_PRINT("\n\tencoded length %u (> packet length %u))", len, length);
453 		return;
454 	}
455 	length = len;
456 
457 	ND_PRINT("\n\tencoded length %u (=Option(s) length %u)", len, len - 4);
458 
459 	if (length == 4)
460 		return;    /* there may be a NULL confreq etc. */
461 
462 	if (ndo->ndo_vflag > 1)
463 		print_unknown_data(ndo, pptr - 2, "\n\t", 6);
464 
465 
466 	switch (code) {
467 	case CPCODES_VEXT:
468 		if (length < 11)
469 			break;
470 		ND_PRINT("\n\t  Magic-Num 0x%08x", GET_BE_U_4(tptr));
471 		tptr += 4;
472 		ND_PRINT(" Vendor: %s (%u)",
473                        tok2str(oui_values,"Unknown",GET_BE_U_3(tptr)),
474                        GET_BE_U_3(tptr));
475 		/* XXX: need to decode Kind and Value(s)? */
476 		break;
477 	case CPCODES_CONF_REQ:
478 	case CPCODES_CONF_ACK:
479 	case CPCODES_CONF_NAK:
480 	case CPCODES_CONF_REJ:
481 		tlen = len - 4;	/* Code(1), Identifier(1) and Length(2) */
482 		do {
483 			switch (proto) {
484 			case PPP_LCP:
485 				pfunc = print_lcp_config_options;
486 				break;
487 			case PPP_IPCP:
488 				pfunc = print_ipcp_config_options;
489 				break;
490 			case PPP_IPV6CP:
491 				pfunc = print_ip6cp_config_options;
492 				break;
493 			case PPP_CCP:
494 				pfunc = print_ccp_config_options;
495 				break;
496 			case PPP_BACP:
497 				pfunc = print_bacp_config_options;
498 				break;
499 			default:
500 				/*
501 				 * No print routine for the options for
502 				 * this protocol.
503 				 */
504 				pfunc = NULL;
505 				break;
506 			}
507 
508 			if (pfunc == NULL) /* catch the above null pointer if unknown CP */
509 				break;
510 
511 			if ((advance = (*pfunc)(ndo, tptr, len)) == 0)
512 				break;
513 			if (tlen < advance) {
514 				ND_PRINT(" [remaining options length %u < %u]",
515 					 tlen, advance);
516 				nd_print_invalid(ndo);
517 				break;
518 			}
519 			tlen -= advance;
520 			tptr += advance;
521 		} while (tlen != 0);
522 		break;
523 
524 	case CPCODES_TERM_REQ:
525 	case CPCODES_TERM_ACK:
526 		/* XXX: need to decode Data? */
527 		break;
528 	case CPCODES_CODE_REJ:
529 		/* XXX: need to decode Rejected-Packet? */
530 		break;
531 	case CPCODES_PROT_REJ:
532 		if (length < 6)
533 			break;
534 		ND_PRINT("\n\t  Rejected %s Protocol (0x%04x)",
535 		       tok2str(ppptype2str,"unknown", GET_BE_U_2(tptr)),
536 		       GET_BE_U_2(tptr));
537 		/* XXX: need to decode Rejected-Information? - hexdump for now */
538 		if (len > 6) {
539 			ND_PRINT("\n\t  Rejected Packet");
540 			print_unknown_data(ndo, tptr + 2, "\n\t    ", len - 2);
541 		}
542 		break;
543 	case CPCODES_ECHO_REQ:
544 	case CPCODES_ECHO_RPL:
545 	case CPCODES_DISC_REQ:
546 		if (length < 8)
547 			break;
548 		ND_PRINT("\n\t  Magic-Num 0x%08x", GET_BE_U_4(tptr));
549 		/* XXX: need to decode Data? - hexdump for now */
550 		if (len > 8) {
551 			ND_PRINT("\n\t  -----trailing data-----");
552 			ND_TCHECK_LEN(tptr + 4, len - 8);
553 			print_unknown_data(ndo, tptr + 4, "\n\t  ", len - 8);
554 		}
555 		break;
556 	case CPCODES_ID:
557 		if (length < 8)
558 			break;
559 		ND_PRINT("\n\t  Magic-Num 0x%08x", GET_BE_U_4(tptr));
560 		/* RFC 1661 says this is intended to be human readable */
561 		if (len > 8) {
562 			ND_PRINT("\n\t  Message\n\t    ");
563 			if (nd_printn(ndo, tptr + 4, len - 4, ndo->ndo_snapend))
564 				goto trunc;
565 		}
566 		break;
567 	case CPCODES_TIME_REM:
568 		if (length < 12)
569 			break;
570 		ND_PRINT("\n\t  Magic-Num 0x%08x", GET_BE_U_4(tptr));
571 		ND_PRINT(", Seconds-Remaining %us", GET_BE_U_4(tptr + 4));
572 		/* XXX: need to decode Message? */
573 		break;
574 	default:
575 		/* XXX this is dirty but we do not get the
576 		 * original pointer passed to the begin
577 		 * the PPP packet */
578 		if (ndo->ndo_vflag <= 1)
579 			print_unknown_data(ndo, pptr - 2, "\n\t  ", length + 2);
580 		break;
581 	}
582 	return;
583 
584 trunc:
585 	ND_PRINT("[|%s]", typestr);
586 }
587 
588 /* LCP config options */
589 static u_int
590 print_lcp_config_options(netdissect_options *ndo,
591                          const u_char *p, u_int length)
592 {
593 	u_int opt, len;
594 
595 	if (length < 2)
596 		return 0;
597 	ND_TCHECK_2(p);
598 	opt = GET_U_1(p);
599 	len = GET_U_1(p + 1);
600 	if (length < len)
601 		return 0;
602 	if (len < 2) {
603 		if (opt < NUM_LCPOPTS)
604 			ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
605 			          lcpconfopts[opt], opt, len);
606 		else
607 			ND_PRINT("\n\tunknown LCP option 0x%02x", opt);
608 		return 0;
609 	}
610 	if (opt < NUM_LCPOPTS)
611 		ND_PRINT("\n\t  %s Option (0x%02x), length %u", lcpconfopts[opt], opt, len);
612 	else {
613 		ND_PRINT("\n\tunknown LCP option 0x%02x", opt);
614 		return len;
615 	}
616 
617 	switch (opt) {
618 	case LCPOPT_VEXT:
619 		if (len < 6) {
620 			ND_PRINT(" (length bogus, should be >= 6)");
621 			return len;
622 		}
623 		ND_PRINT(": Vendor: %s (%u)",
624 			tok2str(oui_values,"Unknown",GET_BE_U_3(p + 2)),
625 			GET_BE_U_3(p + 2));
626 #if 0
627 		ND_PRINT(", kind: 0x%02x", GET_U_1(p + 5));
628 		ND_PRINT(", Value: 0x");
629 		for (i = 0; i < len - 6; i++) {
630 			ND_PRINT("%02x", GET_U_1(p + 6 + i));
631 		}
632 #endif
633 		break;
634 	case LCPOPT_MRU:
635 		if (len != 4) {
636 			ND_PRINT(" (length bogus, should be = 4)");
637 			return len;
638 		}
639 		ND_PRINT(": %u", GET_BE_U_2(p + 2));
640 		break;
641 	case LCPOPT_ACCM:
642 		if (len != 6) {
643 			ND_PRINT(" (length bogus, should be = 6)");
644 			return len;
645 		}
646 		ND_PRINT(": 0x%08x", GET_BE_U_4(p + 2));
647 		break;
648 	case LCPOPT_AP:
649 		if (len < 4) {
650 			ND_PRINT(" (length bogus, should be >= 4)");
651 			return len;
652 		}
653 		ND_PRINT(": %s",
654 			 tok2str(ppptype2str, "Unknown Auth Proto (0x04x)", GET_BE_U_2(p + 2)));
655 
656 		switch (GET_BE_U_2(p + 2)) {
657 		case PPP_CHAP:
658 			ND_PRINT(", %s",
659 				 tok2str(authalg_values, "Unknown Auth Alg %u", GET_U_1(p + 4)));
660 			break;
661 		case PPP_PAP: /* fall through */
662 		case PPP_EAP:
663 		case PPP_SPAP:
664 		case PPP_SPAP_OLD:
665                         break;
666 		default:
667 			print_unknown_data(ndo, p, "\n\t", len);
668 		}
669 		break;
670 	case LCPOPT_QP:
671 		if (len < 4) {
672 			ND_PRINT(" (length bogus, should be >= 4)");
673 			return 0;
674 		}
675 		if (GET_BE_U_2(p + 2) == PPP_LQM)
676 			ND_PRINT(": LQR");
677 		else
678 			ND_PRINT(": unknown");
679 		break;
680 	case LCPOPT_MN:
681 		if (len != 6) {
682 			ND_PRINT(" (length bogus, should be = 6)");
683 			return 0;
684 		}
685 		ND_PRINT(": 0x%08x", GET_BE_U_4(p + 2));
686 		break;
687 	case LCPOPT_PFC:
688 		break;
689 	case LCPOPT_ACFC:
690 		break;
691 	case LCPOPT_LD:
692 		if (len != 4) {
693 			ND_PRINT(" (length bogus, should be = 4)");
694 			return 0;
695 		}
696 		ND_PRINT(": 0x%04x", GET_BE_U_2(p + 2));
697 		break;
698 	case LCPOPT_CBACK:
699 		if (len < 3) {
700 			ND_PRINT(" (length bogus, should be >= 3)");
701 			return 0;
702 		}
703 		ND_PRINT(": ");
704 		ND_PRINT(": Callback Operation %s (%u)",
705                        tok2str(ppp_callback_values, "Unknown", GET_U_1(p + 2)),
706                        GET_U_1(p + 2));
707 		break;
708 	case LCPOPT_MLMRRU:
709 		if (len != 4) {
710 			ND_PRINT(" (length bogus, should be = 4)");
711 			return 0;
712 		}
713 		ND_PRINT(": %u", GET_BE_U_2(p + 2));
714 		break;
715 	case LCPOPT_MLED:
716 		if (len < 3) {
717 			ND_PRINT(" (length bogus, should be >= 3)");
718 			return 0;
719 		}
720 		switch (GET_U_1(p + 2)) {		/* class */
721 		case MEDCLASS_NULL:
722 			ND_PRINT(": Null");
723 			break;
724 		case MEDCLASS_LOCAL:
725 			ND_PRINT(": Local"); /* XXX */
726 			break;
727 		case MEDCLASS_IPV4:
728 			if (len != 7) {
729 				ND_PRINT(" (length bogus, should be = 7)");
730 				return 0;
731 			}
732 			ND_PRINT(": IPv4 %s", GET_IPADDR_STRING(p + 3));
733 			break;
734 		case MEDCLASS_MAC:
735 			if (len != 9) {
736 				ND_PRINT(" (length bogus, should be = 9)");
737 				return 0;
738 			}
739 			ND_PRINT(": MAC %s", GET_ETHERADDR_STRING(p + 3));
740 			break;
741 		case MEDCLASS_MNB:
742 			ND_PRINT(": Magic-Num-Block"); /* XXX */
743 			break;
744 		case MEDCLASS_PSNDN:
745 			ND_PRINT(": PSNDN"); /* XXX */
746 			break;
747 		default:
748 			ND_PRINT(": Unknown class %u", GET_U_1(p + 2));
749 			break;
750 		}
751 		break;
752 
753 /* XXX: to be supported */
754 #if 0
755 	case LCPOPT_DEP6:
756 	case LCPOPT_FCSALT:
757 	case LCPOPT_SDP:
758 	case LCPOPT_NUMMODE:
759 	case LCPOPT_DEP12:
760 	case LCPOPT_DEP14:
761 	case LCPOPT_DEP15:
762 	case LCPOPT_DEP16:
763         case LCPOPT_MLSSNHF:
764 	case LCPOPT_PROP:
765 	case LCPOPT_DCEID:
766 	case LCPOPT_MPP:
767 	case LCPOPT_LCPAOPT:
768 	case LCPOPT_COBS:
769 	case LCPOPT_PE:
770 	case LCPOPT_MLHF:
771 	case LCPOPT_I18N:
772 	case LCPOPT_SDLOS:
773 	case LCPOPT_PPPMUX:
774 		break;
775 #endif
776 	default:
777 		/*
778 		 * Unknown option; dump it as raw bytes now if we're
779 		 * not going to do so below.
780 		 */
781 		if (ndo->ndo_vflag < 2)
782 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
783 		break;
784 	}
785 
786 	if (ndo->ndo_vflag > 1)
787 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
788 
789 	return len;
790 
791 trunc:
792 	ND_PRINT("[|lcp]");
793 	return 0;
794 }
795 
796 /* ML-PPP*/
797 static const struct tok ppp_ml_flag_values[] = {
798     { 0x80, "begin" },
799     { 0x40, "end" },
800     { 0, NULL }
801 };
802 
803 static void
804 handle_mlppp(netdissect_options *ndo,
805              const u_char *p, u_int length)
806 {
807     if (!ndo->ndo_eflag)
808         ND_PRINT("MLPPP, ");
809 
810     if (length < 2) {
811         ND_PRINT("[|mlppp]");
812         return;
813     }
814     if (!ND_TTEST_2(p)) {
815         ND_PRINT("[|mlppp]");
816         return;
817     }
818 
819     ND_PRINT("seq 0x%03x, Flags [%s], length %u",
820            (GET_BE_U_2(p))&0x0fff,
821            /* only support 12-Bit sequence space for now */
822            bittok2str(ppp_ml_flag_values, "none", GET_U_1(p) & 0xc0),
823            length);
824 }
825 
826 /* CHAP */
827 static void
828 handle_chap(netdissect_options *ndo,
829             const u_char *p, u_int length)
830 {
831 	u_int code, len;
832 	u_int val_size, name_size, msg_size;
833 	const u_char *p0;
834 	u_int i;
835 
836 	p0 = p;
837 	if (length < 1) {
838 		ND_PRINT("[|chap]");
839 		return;
840 	} else if (length < 4) {
841 		ND_PRINT("[|chap 0x%02x]", GET_U_1(p));
842 		return;
843 	}
844 
845 	code = GET_U_1(p);
846 	ND_PRINT("CHAP, %s (0x%02x)",
847                tok2str(chapcode_values,"unknown",code),
848                code);
849 	p++;
850 
851 	ND_PRINT(", id %u", GET_U_1(p));	/* ID */
852 	p++;
853 
854 	len = GET_BE_U_2(p);
855 	p += 2;
856 
857 	/*
858 	 * Note that this is a generic CHAP decoding routine. Since we
859 	 * don't know which flavor of CHAP (i.e. CHAP-MD5, MS-CHAPv1,
860 	 * MS-CHAPv2) is used at this point, we can't decode packet
861 	 * specifically to each algorithms. Instead, we simply decode
862 	 * the GCD (Gratest Common Denominator) for all algorithms.
863 	 */
864 	switch (code) {
865 	case CHAP_CHAL:
866 	case CHAP_RESP:
867 		if (length - (p - p0) < 1)
868 			return;
869 		val_size = GET_U_1(p);	/* value size */
870 		p++;
871 		if (length - (p - p0) < val_size)
872 			return;
873 		ND_PRINT(", Value ");
874 		for (i = 0; i < val_size; i++) {
875 			ND_PRINT("%02x", GET_U_1(p));
876 			p++;
877 		}
878 		name_size = len - (u_int)(p - p0);
879 		ND_PRINT(", Name ");
880 		for (i = 0; i < name_size; i++) {
881 			fn_print_char(ndo, GET_U_1(p));
882 			p++;
883 		}
884 		break;
885 	case CHAP_SUCC:
886 	case CHAP_FAIL:
887 		msg_size = len - (u_int)(p - p0);
888 		ND_PRINT(", Msg ");
889 		for (i = 0; i< msg_size; i++) {
890 			fn_print_char(ndo, GET_U_1(p));
891 			p++;
892 		}
893 		break;
894 	}
895 }
896 
897 /* PAP (see RFC 1334) */
898 static void
899 handle_pap(netdissect_options *ndo,
900            const u_char *p, u_int length)
901 {
902 	u_int code, len;
903 	u_int peerid_len, passwd_len, msg_len;
904 	const u_char *p0;
905 	u_int i;
906 
907 	p0 = p;
908 	if (length < 1) {
909 		ND_PRINT("[|pap]");
910 		return;
911 	} else if (length < 4) {
912 		ND_PRINT("[|pap 0x%02x]", GET_U_1(p));
913 		return;
914 	}
915 
916 	code = GET_U_1(p);
917 	ND_PRINT("PAP, %s (0x%02x)",
918 	          tok2str(papcode_values, "unknown", code),
919 	          code);
920 	p++;
921 
922 	ND_PRINT(", id %u", GET_U_1(p));	/* ID */
923 	p++;
924 
925 	len = GET_BE_U_2(p);
926 	p += 2;
927 
928 	if (len > length) {
929 		ND_PRINT(", length %u > packet size", len);
930 		return;
931 	}
932 	length = len;
933 	if (length < (size_t)(p - p0)) {
934 		ND_PRINT(", length %u < PAP header length", length);
935 		return;
936 	}
937 
938 	switch (code) {
939 	case PAP_AREQ:
940 		/* A valid Authenticate-Request is 6 or more octets long. */
941 		if (len < 6)
942 			goto trunc;
943 		if (length - (p - p0) < 1)
944 			return;
945 		peerid_len = GET_U_1(p);	/* Peer-ID Length */
946 		p++;
947 		if (length - (p - p0) < peerid_len)
948 			return;
949 		ND_PRINT(", Peer ");
950 		for (i = 0; i < peerid_len; i++) {
951 			fn_print_char(ndo, GET_U_1(p));
952 			p++;
953 		}
954 
955 		if (length - (p - p0) < 1)
956 			return;
957 		passwd_len = GET_U_1(p);	/* Password Length */
958 		p++;
959 		if (length - (p - p0) < passwd_len)
960 			return;
961 		ND_PRINT(", Name ");
962 		for (i = 0; i < passwd_len; i++) {
963 			fn_print_char(ndo, GET_U_1(p));
964 			p++;
965 		}
966 		break;
967 	case PAP_AACK:
968 	case PAP_ANAK:
969 		/* Although some implementations ignore truncation at
970 		 * this point and at least one generates a truncated
971 		 * packet, RFC 1334 section 2.2.2 clearly states that
972 		 * both AACK and ANAK are at least 5 bytes long.
973 		 */
974 		if (len < 5)
975 			goto trunc;
976 		if (length - (p - p0) < 1)
977 			return;
978 		msg_len = GET_U_1(p);	/* Msg-Length */
979 		p++;
980 		if (length - (p - p0) < msg_len)
981 			return;
982 		ND_PRINT(", Msg ");
983 		for (i = 0; i< msg_len; i++) {
984 			fn_print_char(ndo, GET_U_1(p));
985 			p++;
986 		}
987 		break;
988 	}
989 	return;
990 
991 trunc:
992 	ND_PRINT("[|pap]");
993 }
994 
995 /* BAP */
996 static void
997 handle_bap(netdissect_options *ndo _U_,
998            const u_char *p _U_, u_int length _U_)
999 {
1000 	/* XXX: to be supported!! */
1001 }
1002 
1003 
1004 /* IPCP config options */
1005 static u_int
1006 print_ipcp_config_options(netdissect_options *ndo,
1007                           const u_char *p, u_int length)
1008 {
1009 	u_int opt, len;
1010         u_int compproto, ipcomp_subopttotallen, ipcomp_subopt, ipcomp_suboptlen;
1011 
1012 	if (length < 2)
1013 		return 0;
1014 	ND_TCHECK_2(p);
1015 	opt = GET_U_1(p);
1016 	len = GET_U_1(p + 1);
1017 	if (length < len)
1018 		return 0;
1019 	if (len < 2) {
1020 		ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
1021 		       tok2str(ipcpopt_values,"unknown",opt),
1022 		       opt,
1023 		       len);
1024 		return 0;
1025 	}
1026 
1027 	ND_PRINT("\n\t  %s Option (0x%02x), length %u",
1028 	       tok2str(ipcpopt_values,"unknown",opt),
1029 	       opt,
1030 	       len);
1031 
1032 	switch (opt) {
1033 	case IPCPOPT_2ADDR:		/* deprecated */
1034 		if (len != 10) {
1035 			ND_PRINT(" (length bogus, should be = 10)");
1036 			return len;
1037 		}
1038 		ND_PRINT(": src %s, dst %s",
1039 		       GET_IPADDR_STRING(p + 2),
1040 		       GET_IPADDR_STRING(p + 6));
1041 		break;
1042 	case IPCPOPT_IPCOMP:
1043 		if (len < 4) {
1044 			ND_PRINT(" (length bogus, should be >= 4)");
1045 			return 0;
1046 		}
1047 		compproto = GET_BE_U_2(p + 2);
1048 
1049 		ND_PRINT(": %s (0x%02x):",
1050 		          tok2str(ipcpopt_compproto_values, "Unknown", compproto),
1051 		          compproto);
1052 
1053 		switch (compproto) {
1054                 case PPP_VJC:
1055 			/* XXX: VJ-Comp parameters should be decoded */
1056                         break;
1057                 case IPCPOPT_IPCOMP_HDRCOMP:
1058                         if (len < IPCPOPT_IPCOMP_MINLEN) {
1059                                 ND_PRINT(" (length bogus, should be >= %u)",
1060                                          IPCPOPT_IPCOMP_MINLEN);
1061                                 return 0;
1062                         }
1063 
1064                         ND_TCHECK_LEN(p + 2, IPCPOPT_IPCOMP_MINLEN);
1065                         ND_PRINT("\n\t    TCP Space %u, non-TCP Space %u"
1066                                ", maxPeriod %u, maxTime %u, maxHdr %u",
1067                                GET_BE_U_2(p + 4),
1068                                GET_BE_U_2(p + 6),
1069                                GET_BE_U_2(p + 8),
1070                                GET_BE_U_2(p + 10),
1071                                GET_BE_U_2(p + 12));
1072 
1073                         /* suboptions present ? */
1074                         if (len > IPCPOPT_IPCOMP_MINLEN) {
1075                                 ipcomp_subopttotallen = len - IPCPOPT_IPCOMP_MINLEN;
1076                                 p += IPCPOPT_IPCOMP_MINLEN;
1077 
1078                                 ND_PRINT("\n\t      Suboptions, length %u", ipcomp_subopttotallen);
1079 
1080                                 while (ipcomp_subopttotallen >= 2) {
1081                                         ND_TCHECK_2(p);
1082                                         ipcomp_subopt = GET_U_1(p);
1083                                         ipcomp_suboptlen = GET_U_1(p + 1);
1084 
1085                                         /* sanity check */
1086                                         if (ipcomp_subopt == 0 ||
1087                                             ipcomp_suboptlen == 0 )
1088                                                 break;
1089 
1090                                         /* XXX: just display the suboptions for now */
1091                                         ND_PRINT("\n\t\t%s Suboption #%u, length %u",
1092                                                tok2str(ipcpopt_compproto_subopt_values,
1093                                                        "Unknown",
1094                                                        ipcomp_subopt),
1095                                                ipcomp_subopt,
1096                                                ipcomp_suboptlen);
1097                                         if (ipcomp_subopttotallen < ipcomp_suboptlen) {
1098                                                 ND_PRINT(" [remaining suboptions length %u < %u]",
1099                                                          ipcomp_subopttotallen, ipcomp_suboptlen);
1100                                                 nd_print_invalid(ndo);
1101                                                 break;
1102                                         }
1103                                         ipcomp_subopttotallen -= ipcomp_suboptlen;
1104                                         p += ipcomp_suboptlen;
1105                                 }
1106                         }
1107                         break;
1108                 default:
1109                         break;
1110 		}
1111 		break;
1112 
1113 	case IPCPOPT_ADDR:     /* those options share the same format - fall through */
1114 	case IPCPOPT_MOBILE4:
1115 	case IPCPOPT_PRIDNS:
1116 	case IPCPOPT_PRINBNS:
1117 	case IPCPOPT_SECDNS:
1118 	case IPCPOPT_SECNBNS:
1119 		if (len != 6) {
1120 			ND_PRINT(" (length bogus, should be = 6)");
1121 			return 0;
1122 		}
1123 		ND_PRINT(": %s", GET_IPADDR_STRING(p + 2));
1124 		break;
1125 	default:
1126 		/*
1127 		 * Unknown option; dump it as raw bytes now if we're
1128 		 * not going to do so below.
1129 		 */
1130 		if (ndo->ndo_vflag < 2)
1131 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
1132 		break;
1133 	}
1134 	if (ndo->ndo_vflag > 1)
1135 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
1136 	return len;
1137 
1138 trunc:
1139 	ND_PRINT("[|ipcp]");
1140 	return 0;
1141 }
1142 
1143 /* IP6CP config options */
1144 static u_int
1145 print_ip6cp_config_options(netdissect_options *ndo,
1146                            const u_char *p, u_int length)
1147 {
1148 	u_int opt, len;
1149 
1150 	if (length < 2)
1151 		return 0;
1152 	ND_TCHECK_2(p);
1153 	opt = GET_U_1(p);
1154 	len = GET_U_1(p + 1);
1155 	if (length < len)
1156 		return 0;
1157 	if (len < 2) {
1158 		ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
1159 		       tok2str(ip6cpopt_values,"unknown",opt),
1160 		       opt,
1161 		       len);
1162 		return 0;
1163 	}
1164 
1165 	ND_PRINT("\n\t  %s Option (0x%02x), length %u",
1166 	       tok2str(ip6cpopt_values,"unknown",opt),
1167 	       opt,
1168 	       len);
1169 
1170 	switch (opt) {
1171 	case IP6CP_IFID:
1172 		if (len != 10) {
1173 			ND_PRINT(" (length bogus, should be = 10)");
1174 			return len;
1175 		}
1176 		ND_TCHECK_8(p + 2);
1177 		ND_PRINT(": %04x:%04x:%04x:%04x",
1178 		       GET_BE_U_2(p + 2),
1179 		       GET_BE_U_2(p + 4),
1180 		       GET_BE_U_2(p + 6),
1181 		       GET_BE_U_2(p + 8));
1182 		break;
1183 	default:
1184 		/*
1185 		 * Unknown option; dump it as raw bytes now if we're
1186 		 * not going to do so below.
1187 		 */
1188 		if (ndo->ndo_vflag < 2)
1189 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
1190 		break;
1191 	}
1192 	if (ndo->ndo_vflag > 1)
1193 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
1194 
1195 	return len;
1196 
1197 trunc:
1198 	ND_PRINT("[|ip6cp]");
1199 	return 0;
1200 }
1201 
1202 
1203 /* CCP config options */
1204 static u_int
1205 print_ccp_config_options(netdissect_options *ndo,
1206                          const u_char *p, u_int length)
1207 {
1208 	u_int opt, len;
1209 
1210 	if (length < 2)
1211 		return 0;
1212 	ND_TCHECK_2(p);
1213 	opt = GET_U_1(p);
1214 	len = GET_U_1(p + 1);
1215 	if (length < len)
1216 		return 0;
1217 	if (len < 2) {
1218 		ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
1219 		          tok2str(ccpconfopts_values, "Unknown", opt),
1220 		          opt,
1221 		          len);
1222 		return 0;
1223 	}
1224 
1225 	ND_PRINT("\n\t  %s Option (0x%02x), length %u",
1226 	          tok2str(ccpconfopts_values, "Unknown", opt),
1227 	          opt,
1228 	          len);
1229 
1230 	switch (opt) {
1231 	case CCPOPT_BSDCOMP:
1232 		if (len < 3) {
1233 			ND_PRINT(" (length bogus, should be >= 3)");
1234 			return len;
1235 		}
1236 		ND_PRINT(": Version: %u, Dictionary Bits: %u",
1237 			GET_U_1(p + 2) >> 5,
1238 			GET_U_1(p + 2) & 0x1f);
1239 		break;
1240 	case CCPOPT_MVRCA:
1241 		if (len < 4) {
1242 			ND_PRINT(" (length bogus, should be >= 4)");
1243 			return len;
1244 		}
1245 		ND_PRINT(": Features: %u, PxP: %s, History: %u, #CTX-ID: %u",
1246 				(GET_U_1(p + 2) & 0xc0) >> 6,
1247 				(GET_U_1(p + 2) & 0x20) ? "Enabled" : "Disabled",
1248 				GET_U_1(p + 2) & 0x1f,
1249 				GET_U_1(p + 3));
1250 		break;
1251 	case CCPOPT_DEFLATE:
1252 		if (len < 4) {
1253 			ND_PRINT(" (length bogus, should be >= 4)");
1254 			return len;
1255 		}
1256 		ND_PRINT(": Window: %uK, Method: %s (0x%x), MBZ: %u, CHK: %u",
1257 			(GET_U_1(p + 2) & 0xf0) >> 4,
1258 			((GET_U_1(p + 2) & 0x0f) == 8) ? "zlib" : "unknown",
1259 			GET_U_1(p + 2) & 0x0f,
1260 			(GET_U_1(p + 3) & 0xfc) >> 2,
1261 			GET_U_1(p + 3) & 0x03);
1262 		break;
1263 
1264 /* XXX: to be supported */
1265 #if 0
1266 	case CCPOPT_OUI:
1267 	case CCPOPT_PRED1:
1268 	case CCPOPT_PRED2:
1269 	case CCPOPT_PJUMP:
1270 	case CCPOPT_HPPPC:
1271 	case CCPOPT_STACLZS:
1272 	case CCPOPT_MPPC:
1273 	case CCPOPT_GFZA:
1274 	case CCPOPT_V42BIS:
1275 	case CCPOPT_LZSDCP:
1276 	case CCPOPT_DEC:
1277 	case CCPOPT_RESV:
1278 		break;
1279 #endif
1280 	default:
1281 		/*
1282 		 * Unknown option; dump it as raw bytes now if we're
1283 		 * not going to do so below.
1284 		 */
1285 		if (ndo->ndo_vflag < 2)
1286 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
1287 		break;
1288 	}
1289 	if (ndo->ndo_vflag > 1)
1290 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
1291 
1292 	return len;
1293 
1294 trunc:
1295 	ND_PRINT("[|ccp]");
1296 	return 0;
1297 }
1298 
1299 /* BACP config options */
1300 static u_int
1301 print_bacp_config_options(netdissect_options *ndo,
1302                           const u_char *p, u_int length)
1303 {
1304 	u_int opt, len;
1305 
1306 	if (length < 2)
1307 		return 0;
1308 	ND_TCHECK_2(p);
1309 	opt = GET_U_1(p);
1310 	len = GET_U_1(p + 1);
1311 	if (length < len)
1312 		return 0;
1313 	if (len < 2) {
1314 		ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
1315 		          tok2str(bacconfopts_values, "Unknown", opt),
1316 		          opt,
1317 		          len);
1318 		return 0;
1319 	}
1320 
1321 	ND_PRINT("\n\t  %s Option (0x%02x), length %u",
1322 	          tok2str(bacconfopts_values, "Unknown", opt),
1323 	          opt,
1324 	          len);
1325 
1326 	switch (opt) {
1327 	case BACPOPT_FPEER:
1328 		if (len != 6) {
1329 			ND_PRINT(" (length bogus, should be = 6)");
1330 			return len;
1331 		}
1332 		ND_PRINT(": Magic-Num 0x%08x", GET_BE_U_4(p + 2));
1333 		break;
1334 	default:
1335 		/*
1336 		 * Unknown option; dump it as raw bytes now if we're
1337 		 * not going to do so below.
1338 		 */
1339 		if (ndo->ndo_vflag < 2)
1340 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
1341 		break;
1342 	}
1343 	if (ndo->ndo_vflag > 1)
1344 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
1345 
1346 	return len;
1347 
1348 trunc:
1349 	ND_PRINT("[|bacp]");
1350 	return 0;
1351 }
1352 
1353 /*
1354  * Un-escape RFC 1662 PPP in HDLC-like framing, with octet escapes.
1355  * The length argument is the on-the-wire length, not the captured
1356  * length; we can only un-escape the captured part.
1357  */
1358 static void
1359 ppp_hdlc(netdissect_options *ndo,
1360          const u_char *p, u_int length)
1361 {
1362 	u_int caplen = ND_BYTES_AVAILABLE_AFTER(p);
1363 	u_char *b, *t, c;
1364 	const u_char *s;
1365 	u_int i, proto;
1366 	const void *sb, *se;
1367 
1368 	if (caplen == 0)
1369 		return;
1370 
1371         if (length == 0)
1372                 return;
1373 
1374 	b = (u_char *)nd_malloc(ndo, caplen);
1375 	if (b == NULL)
1376 		return;
1377 
1378 	/*
1379 	 * Unescape all the data into a temporary, private, buffer.
1380 	 * Do this so that we don't overwrite the original packet
1381 	 * contents.
1382 	 */
1383 	for (s = p, t = b, i = caplen; i != 0; i--) {
1384 		c = GET_U_1(s);
1385 		s++;
1386 		if (c == 0x7d) {
1387 			if (i <= 1)
1388 				break;
1389 			i--;
1390 			c = GET_U_1(s) ^ 0x20;
1391 			s++;
1392 		}
1393 		*t++ = c;
1394 	}
1395 
1396 	/*
1397 	 * Change the end pointer, so bounds checks work.
1398 	 * Change the pointer to packet data to help debugging.
1399 	 */
1400 	sb = ndo->ndo_packetp;
1401 	se = ndo->ndo_snapend;
1402 	ndo->ndo_packetp = b;
1403 	ndo->ndo_snapend = t;
1404 	length = ND_BYTES_AVAILABLE_AFTER(b);
1405 
1406         /* now lets guess about the payload codepoint format */
1407         if (length < 1)
1408                 goto trunc;
1409         proto = GET_U_1(b); /* start with a one-octet codepoint guess */
1410 
1411         switch (proto) {
1412         case PPP_IP:
1413 		ip_print(ndo, b + 1, length - 1);
1414 		goto cleanup;
1415         case PPP_IPV6:
1416 		ip6_print(ndo, b + 1, length - 1);
1417 		goto cleanup;
1418         default: /* no luck - try next guess */
1419 		break;
1420         }
1421 
1422         if (length < 2)
1423                 goto trunc;
1424         proto = GET_BE_U_2(b); /* next guess - load two octets */
1425 
1426         switch (proto) {
1427         case (PPP_ADDRESS << 8 | PPP_CONTROL): /* looks like a PPP frame */
1428             if (length < 4)
1429                 goto trunc;
1430             proto = GET_BE_U_2(b + 2); /* load the PPP proto-id */
1431             if ((proto & 0xff00) == 0x7e00)
1432                 ND_PRINT("(protocol 0x%04x invalid)", proto);
1433             else
1434                 handle_ppp(ndo, proto, b + 4, length - 4);
1435             break;
1436         default: /* last guess - proto must be a PPP proto-id */
1437             if ((proto & 0xff00) == 0x7e00)
1438                 ND_PRINT("(protocol 0x%04x invalid)", proto);
1439             else
1440                 handle_ppp(ndo, proto, b + 2, length - 2);
1441             break;
1442         }
1443 
1444 cleanup:
1445 	ndo->ndo_packetp = sb;
1446 	ndo->ndo_snapend = se;
1447         return;
1448 
1449 trunc:
1450 	ndo->ndo_packetp = sb;
1451 	ndo->ndo_snapend = se;
1452 	nd_print_trunc(ndo);
1453 }
1454 
1455 
1456 /* PPP */
1457 static void
1458 handle_ppp(netdissect_options *ndo,
1459            u_int proto, const u_char *p, u_int length)
1460 {
1461 	if ((proto & 0xff00) == 0x7e00) { /* is this an escape code ? */
1462 		ppp_hdlc(ndo, p - 1, length);
1463 		return;
1464 	}
1465 
1466 	switch (proto) {
1467 	case PPP_LCP: /* fall through */
1468 	case PPP_IPCP:
1469 	case PPP_OSICP:
1470 	case PPP_MPLSCP:
1471 	case PPP_IPV6CP:
1472 	case PPP_CCP:
1473 	case PPP_BACP:
1474 		handle_ctrl_proto(ndo, proto, p, length);
1475 		break;
1476 	case PPP_ML:
1477 		handle_mlppp(ndo, p, length);
1478 		break;
1479 	case PPP_CHAP:
1480 		handle_chap(ndo, p, length);
1481 		break;
1482 	case PPP_PAP:
1483 		handle_pap(ndo, p, length);
1484 		break;
1485 	case PPP_BAP:		/* XXX: not yet completed */
1486 		handle_bap(ndo, p, length);
1487 		break;
1488 	case ETHERTYPE_IP:	/*XXX*/
1489         case PPP_VJNC:
1490 	case PPP_IP:
1491 		ip_print(ndo, p, length);
1492 		break;
1493 	case ETHERTYPE_IPV6:	/*XXX*/
1494 	case PPP_IPV6:
1495 		ip6_print(ndo, p, length);
1496 		break;
1497 	case ETHERTYPE_IPX:	/*XXX*/
1498 	case PPP_IPX:
1499 		ipx_print(ndo, p, length);
1500 		break;
1501 	case PPP_OSI:
1502 		isoclns_print(ndo, p, length);
1503 		break;
1504 	case PPP_MPLS_UCAST:
1505 	case PPP_MPLS_MCAST:
1506 		mpls_print(ndo, p, length);
1507 		break;
1508 	case PPP_COMP:
1509 		ND_PRINT("compressed PPP data");
1510 		break;
1511 	default:
1512 		ND_PRINT("%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto));
1513 		print_unknown_data(ndo, p, "\n\t", length);
1514 		break;
1515 	}
1516 }
1517 
1518 /* Standard PPP printer */
1519 u_int
1520 ppp_print(netdissect_options *ndo,
1521           const u_char *p, u_int length)
1522 {
1523 	u_int proto,ppp_header;
1524         u_int olen = length; /* _o_riginal length */
1525 	u_int hdr_len = 0;
1526 
1527 	ndo->ndo_protocol = "ppp";
1528 	/*
1529 	 * Here, we assume that p points to the Address and Control
1530 	 * field (if they present).
1531 	 */
1532 	if (length < 2)
1533 		goto trunc;
1534         ppp_header = GET_BE_U_2(p);
1535 
1536         switch(ppp_header) {
1537         case (PPP_PPPD_IN  << 8 | PPP_CONTROL):
1538             if (ndo->ndo_eflag) ND_PRINT("In  ");
1539             p += 2;
1540             length -= 2;
1541             hdr_len += 2;
1542             break;
1543         case (PPP_PPPD_OUT << 8 | PPP_CONTROL):
1544             if (ndo->ndo_eflag) ND_PRINT("Out ");
1545             p += 2;
1546             length -= 2;
1547             hdr_len += 2;
1548             break;
1549         case (PPP_ADDRESS << 8 | PPP_CONTROL):
1550             p += 2;			/* ACFC not used */
1551             length -= 2;
1552             hdr_len += 2;
1553             break;
1554 
1555         default:
1556             break;
1557         }
1558 
1559 	if (length < 2)
1560 		goto trunc;
1561 	if (GET_U_1(p) % 2) {
1562 		proto = GET_U_1(p);	/* PFC is used */
1563 		p++;
1564 		length--;
1565 		hdr_len++;
1566 	} else {
1567 		proto = GET_BE_U_2(p);
1568 		p += 2;
1569 		length -= 2;
1570 		hdr_len += 2;
1571 	}
1572 
1573 	if (ndo->ndo_eflag) {
1574 		const char *typestr;
1575 		typestr = tok2str(ppptype2str, "unknown", proto);
1576 		ND_PRINT("%s (0x%04x), length %u",
1577 		          typestr,
1578 		          proto,
1579 		          olen);
1580 		if (*typestr == 'u')	/* "unknown" */
1581 			return hdr_len;
1582 
1583 		ND_PRINT(": ");
1584 	}
1585 
1586 	handle_ppp(ndo, proto, p, length);
1587 	return (hdr_len);
1588 trunc:
1589 	nd_print_trunc(ndo);
1590 	return (0);
1591 }
1592 
1593 
1594 /* PPP I/F printer */
1595 void
1596 ppp_if_print(netdissect_options *ndo,
1597              const struct pcap_pkthdr *h, const u_char *p)
1598 {
1599 	u_int length = h->len;
1600 	u_int caplen = h->caplen;
1601 
1602 	ndo->ndo_protocol = "ppp";
1603 	if (caplen < PPP_HDRLEN) {
1604 		nd_print_trunc(ndo);
1605 		ndo->ndo_ll_hdr_len += caplen;
1606 		return;
1607 	}
1608 	ndo->ndo_ll_hdr_len += PPP_HDRLEN;
1609 
1610 #if 0
1611 	/*
1612 	 * XXX: seems to assume that there are 2 octets prepended to an
1613 	 * actual PPP frame. The 1st octet looks like Input/Output flag
1614 	 * while 2nd octet is unknown, at least to me
1615 	 * (mshindo@mshindo.net).
1616 	 *
1617 	 * That was what the original tcpdump code did.
1618 	 *
1619 	 * FreeBSD's "if_ppp.c" *does* set the first octet to 1 for outbound
1620 	 * packets and 0 for inbound packets - but only if the
1621 	 * protocol field has the 0x8000 bit set (i.e., it's a network
1622 	 * control protocol); it does so before running the packet through
1623 	 * "bpf_filter" to see if it should be discarded, and to see
1624 	 * if we should update the time we sent the most recent packet...
1625 	 *
1626 	 * ...but it puts the original address field back after doing
1627 	 * so.
1628 	 *
1629 	 * NetBSD's "if_ppp.c" doesn't set the first octet in that fashion.
1630 	 *
1631 	 * I don't know if any PPP implementation handed up to a BPF
1632 	 * device packets with the first octet being 1 for outbound and
1633 	 * 0 for inbound packets, so I (guy@alum.mit.edu) don't know
1634 	 * whether that ever needs to be checked or not.
1635 	 *
1636 	 * Note that NetBSD has a DLT_PPP_SERIAL, which it uses for PPP,
1637 	 * and its tcpdump appears to assume that the frame always
1638 	 * begins with an address field and a control field, and that
1639 	 * the address field might be 0x0f or 0x8f, for Cisco
1640 	 * point-to-point with HDLC framing as per section 4.3.1 of RFC
1641 	 * 1547, as well as 0xff, for PPP in HDLC-like framing as per
1642 	 * RFC 1662.
1643 	 *
1644 	 * (Is the Cisco framing in question what DLT_C_HDLC, in
1645 	 * BSD/OS, is?)
1646 	 */
1647 	if (ndo->ndo_eflag)
1648 		ND_PRINT("%c %4d %02x ", GET_U_1(p) ? 'O' : 'I',
1649 			 length, GET_U_1(p + 1));
1650 #endif
1651 
1652 	ppp_print(ndo, p, length);
1653 }
1654 
1655 /*
1656  * PPP I/F printer to use if we know that RFC 1662-style PPP in HDLC-like
1657  * framing, or Cisco PPP with HDLC framing as per section 4.3.1 of RFC 1547,
1658  * is being used (i.e., we don't check for PPP_ADDRESS and PPP_CONTROL,
1659  * discard them *if* those are the first two octets, and parse the remaining
1660  * packet as a PPP packet, as "ppp_print()" does).
1661  *
1662  * This handles, for example, DLT_PPP_SERIAL in NetBSD.
1663  */
1664 void
1665 ppp_hdlc_if_print(netdissect_options *ndo,
1666                   const struct pcap_pkthdr *h, const u_char *p)
1667 {
1668 	u_int length = h->len;
1669 	u_int caplen = h->caplen;
1670 	u_int proto;
1671 	u_int hdrlen = 0;
1672 
1673 	ndo->ndo_protocol = "ppp_hdlc";
1674 	if (caplen < 2) {
1675 		nd_print_trunc(ndo);
1676 		ndo->ndo_ll_hdr_len += caplen;
1677 		return;
1678 	}
1679 
1680 	switch (GET_U_1(p)) {
1681 
1682 	case PPP_ADDRESS:
1683 		if (caplen < 4) {
1684 			nd_print_trunc(ndo);
1685 			ndo->ndo_ll_hdr_len += caplen;
1686 			return;
1687 		}
1688 
1689 		if (ndo->ndo_eflag)
1690 			ND_PRINT("%02x %02x %u ", GET_U_1(p),
1691 				 GET_U_1(p + 1), length);
1692 		p += 2;
1693 		length -= 2;
1694 		hdrlen += 2;
1695 
1696 		proto = GET_BE_U_2(p);
1697 		p += 2;
1698 		length -= 2;
1699 		hdrlen += 2;
1700 		ND_PRINT("%s: ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto));
1701 
1702 		handle_ppp(ndo, proto, p, length);
1703 		break;
1704 
1705 	case CHDLC_UNICAST:
1706 	case CHDLC_BCAST:
1707 		chdlc_if_print(ndo, h, p);
1708 		return;
1709 
1710 	default:
1711 		if (caplen < 4) {
1712 			nd_print_trunc(ndo);
1713 			ndo->ndo_ll_hdr_len += caplen;
1714 			return;
1715 		}
1716 
1717 		if (ndo->ndo_eflag)
1718 			ND_PRINT("%02x %02x %u ", GET_U_1(p),
1719 				 GET_U_1(p + 1), length);
1720 		p += 2;
1721 		hdrlen += 2;
1722 
1723 		/*
1724 		 * XXX - NetBSD's "ppp_netbsd_serial_if_print()" treats
1725 		 * the next two octets as an Ethernet type; does that
1726 		 * ever happen?
1727 		 */
1728 		ND_PRINT("unknown addr %02x; ctrl %02x", GET_U_1(p),
1729 			 GET_U_1(p + 1));
1730 		break;
1731 	}
1732 
1733 	ndo->ndo_ll_hdr_len += hdrlen;
1734 }
1735 
1736 #define PPP_BSDI_HDRLEN 24
1737 
1738 /* BSD/OS specific PPP printer */
1739 void
1740 ppp_bsdos_if_print(netdissect_options *ndo,
1741                    const struct pcap_pkthdr *h _U_, const u_char *p _U_)
1742 {
1743 	u_int hdrlength;
1744 #ifdef __bsdi__
1745 	u_int length = h->len;
1746 	u_int caplen = h->caplen;
1747 	uint16_t ptype;
1748 	uint8_t llhl;
1749 	const u_char *q;
1750 	u_int i;
1751 
1752 	ndo->ndo_protocol = "ppp_bsdos";
1753 	if (caplen < PPP_BSDI_HDRLEN) {
1754 		nd_print_trunc(ndo);
1755 		ndo->ndo_ll_hdr_len += caplen;
1756 		return;
1757 	}
1758 
1759 	hdrlength = 0;
1760 
1761 #if 0
1762 	if (GET_U_1(p) == PPP_ADDRESS &&
1763 	    GET_U_1(p + 1) == PPP_CONTROL) {
1764 		if (ndo->ndo_eflag)
1765 			ND_PRINT("%02x %02x ", GET_U_1(p),
1766 				 GET_U_1(p + 1));
1767 		p += 2;
1768 		hdrlength = 2;
1769 	}
1770 
1771 	if (ndo->ndo_eflag)
1772 		ND_PRINT("%u ", length);
1773 	/* Retrieve the protocol type */
1774 	if (GET_U_1(p) & 01) {
1775 		/* Compressed protocol field */
1776 		ptype = GET_U_1(p);
1777 		if (ndo->ndo_eflag)
1778 			ND_PRINT("%02x ", ptype);
1779 		p++;
1780 		hdrlength += 1;
1781 	} else {
1782 		/* Un-compressed protocol field */
1783 		ptype = GET_BE_U_2(p);
1784 		if (ndo->ndo_eflag)
1785 			ND_PRINT("%04x ", ptype);
1786 		p += 2;
1787 		hdrlength += 2;
1788 	}
1789 #else
1790 	ptype = 0;	/*XXX*/
1791 	if (ndo->ndo_eflag)
1792 		ND_PRINT("%c ", GET_U_1(p + SLC_DIR) ? 'O' : 'I');
1793 	llhl = GET_U_1(p + SLC_LLHL);
1794 	if (llhl) {
1795 		/* link level header */
1796 		struct ppp_header *ph;
1797 
1798 		q = p + SLC_BPFHDRLEN;
1799 		ph = (struct ppp_header *)q;
1800 		if (ph->phdr_addr == PPP_ADDRESS
1801 		 && ph->phdr_ctl == PPP_CONTROL) {
1802 			if (ndo->ndo_eflag)
1803 				ND_PRINT("%02x %02x ", GET_U_1(q),
1804 					 GET_U_1(q + 1));
1805 			ptype = GET_BE_U_2(&ph->phdr_type);
1806 			if (ndo->ndo_eflag && (ptype == PPP_VJC || ptype == PPP_VJNC)) {
1807 				ND_PRINT("%s ", tok2str(ppptype2str,
1808 						"proto-#%u", ptype));
1809 			}
1810 		} else {
1811 			if (ndo->ndo_eflag) {
1812 				ND_PRINT("LLH=[");
1813 				for (i = 0; i < llhl; i++)
1814 					ND_PRINT("%02x", GET_U_1(q + i));
1815 				ND_PRINT("] ");
1816 			}
1817 		}
1818 	}
1819 	if (ndo->ndo_eflag)
1820 		ND_PRINT("%u ", length);
1821 	if (GET_U_1(p + SLC_CHL)) {
1822 		q = p + SLC_BPFHDRLEN + llhl;
1823 
1824 		switch (ptype) {
1825 		case PPP_VJC:
1826 			ptype = vjc_print(ndo, q, ptype);
1827 			hdrlength = PPP_BSDI_HDRLEN;
1828 			p += hdrlength;
1829 			switch (ptype) {
1830 			case PPP_IP:
1831 				ip_print(ndo, p, length);
1832 				break;
1833 			case PPP_IPV6:
1834 				ip6_print(ndo, p, length);
1835 				break;
1836 			case PPP_MPLS_UCAST:
1837 			case PPP_MPLS_MCAST:
1838 				mpls_print(ndo, p, length);
1839 				break;
1840 			}
1841 			goto printx;
1842 		case PPP_VJNC:
1843 			ptype = vjc_print(ndo, q, ptype);
1844 			hdrlength = PPP_BSDI_HDRLEN;
1845 			p += hdrlength;
1846 			switch (ptype) {
1847 			case PPP_IP:
1848 				ip_print(ndo, p, length);
1849 				break;
1850 			case PPP_IPV6:
1851 				ip6_print(ndo, p, length);
1852 				break;
1853 			case PPP_MPLS_UCAST:
1854 			case PPP_MPLS_MCAST:
1855 				mpls_print(ndo, p, length);
1856 				break;
1857 			}
1858 			goto printx;
1859 		default:
1860 			if (ndo->ndo_eflag) {
1861 				ND_PRINT("CH=[");
1862 				for (i = 0; i < llhl; i++)
1863 					ND_PRINT("%02x",
1864 					    GET_U_1(q + i));
1865 				ND_PRINT("] ");
1866 			}
1867 			break;
1868 		}
1869 	}
1870 
1871 	hdrlength = PPP_BSDI_HDRLEN;
1872 #endif
1873 
1874 	length -= hdrlength;
1875 	p += hdrlength;
1876 
1877 	switch (ptype) {
1878 	case PPP_IP:
1879 		ip_print(p, length);
1880 		break;
1881 	case PPP_IPV6:
1882 		ip6_print(ndo, p, length);
1883 		break;
1884 	case PPP_MPLS_UCAST:
1885 	case PPP_MPLS_MCAST:
1886 		mpls_print(ndo, p, length);
1887 		break;
1888 	default:
1889 		ND_PRINT("%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", ptype));
1890 	}
1891 
1892 printx:
1893 #else /* __bsdi */
1894 	hdrlength = 0;
1895 #endif /* __bsdi__ */
1896 	ndo->ndo_ll_hdr_len += hdrlength;
1897 }
1898