xref: /netbsd-src/external/bsd/tcpdump/dist/print-ppp.c (revision 3117ece4fc4a4ca4489ba793710b60b0d26bab6c)
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 #include <sys/cdefs.h>
35 #ifndef lint
36 __RCSID("$NetBSD: print-ppp.c,v 1.11 2024/09/02 16:15:32 christos Exp $");
37 #endif
38 
39 #include <config.h>
40 
41 #include "netdissect-stdinc.h"
42 
43 #include <stdlib.h>
44 
45 #ifdef __bsdi__
46 #include <net/slcompress.h>
47 #include <net/if_ppp.h>
48 #endif
49 
50 #include "netdissect.h"
51 #include "extract.h"
52 #include "addrtoname.h"
53 #include "ppp.h"
54 #include "chdlc.h"
55 #include "ethertype.h"
56 #include "oui.h"
57 #include "netdissect-alloc.h"
58 
59 /*
60  * The following constants are defined by IANA. Please refer to
61  *    https://www.isi.edu/in-notes/iana/assignments/ppp-numbers
62  * for the up-to-date information.
63  */
64 
65 /* Protocol Codes defined in ppp.h */
66 
67 static const struct tok ppptype2str[] = {
68         { PPP_IP,	  "IP" },
69         { PPP_OSI,	  "OSI" },
70         { PPP_NS,	  "NS" },
71         { PPP_DECNET,	  "DECNET" },
72         { PPP_APPLE,	  "APPLE" },
73 	{ PPP_IPX,	  "IPX" },
74 	{ PPP_VJC,	  "VJC IP" },
75 	{ PPP_VJNC,	  "VJNC IP" },
76 	{ PPP_BRPDU,	  "BRPDU" },
77 	{ PPP_STII,	  "STII" },
78 	{ PPP_VINES,	  "VINES" },
79 	{ PPP_MPLS_UCAST, "MPLS" },
80 	{ PPP_MPLS_MCAST, "MPLS" },
81         { PPP_COMP,       "Compressed"},
82         { PPP_ML,         "MLPPP"},
83         { PPP_IPV6,       "IP6"},
84 
85 	{ PPP_HELLO,	  "HELLO" },
86 	{ PPP_LUXCOM,	  "LUXCOM" },
87 	{ PPP_SNS,	  "SNS" },
88 	{ PPP_IPCP,	  "IPCP" },
89 	{ PPP_OSICP,	  "OSICP" },
90 	{ PPP_NSCP,	  "NSCP" },
91 	{ PPP_DECNETCP,   "DECNETCP" },
92 	{ PPP_APPLECP,	  "APPLECP" },
93 	{ PPP_IPXCP,	  "IPXCP" },
94 	{ PPP_STIICP,	  "STIICP" },
95 	{ PPP_VINESCP,	  "VINESCP" },
96         { PPP_IPV6CP,     "IP6CP" },
97 	{ PPP_MPLSCP,	  "MPLSCP" },
98 
99 	{ PPP_LCP,	  "LCP" },
100 	{ PPP_PAP,	  "PAP" },
101 	{ PPP_LQM,	  "LQM" },
102 	{ PPP_CHAP,	  "CHAP" },
103 	{ PPP_EAP,	  "EAP" },
104 	{ PPP_SPAP,	  "SPAP" },
105 	{ PPP_SPAP_OLD,	  "Old-SPAP" },
106 	{ PPP_BACP,	  "BACP" },
107 	{ PPP_BAP,	  "BAP" },
108 	{ PPP_MPCP,	  "MLPPP-CP" },
109 	{ PPP_CCP,	  "CCP" },
110 	{ 0,		  NULL }
111 };
112 
113 /* Control Protocols (LCP/IPCP/CCP etc.) Codes defined in RFC 1661 */
114 
115 #define CPCODES_VEXT		0	/* Vendor-Specific (RFC2153) */
116 #define CPCODES_CONF_REQ	1	/* Configure-Request */
117 #define CPCODES_CONF_ACK	2	/* Configure-Ack */
118 #define CPCODES_CONF_NAK	3	/* Configure-Nak */
119 #define CPCODES_CONF_REJ	4	/* Configure-Reject */
120 #define CPCODES_TERM_REQ	5	/* Terminate-Request */
121 #define CPCODES_TERM_ACK	6	/* Terminate-Ack */
122 #define CPCODES_CODE_REJ	7	/* Code-Reject */
123 #define CPCODES_PROT_REJ	8	/* Protocol-Reject (LCP only) */
124 #define CPCODES_ECHO_REQ	9	/* Echo-Request (LCP only) */
125 #define CPCODES_ECHO_RPL	10	/* Echo-Reply (LCP only) */
126 #define CPCODES_DISC_REQ	11	/* Discard-Request (LCP only) */
127 #define CPCODES_ID		12	/* Identification (LCP only) RFC1570 */
128 #define CPCODES_TIME_REM	13	/* Time-Remaining (LCP only) RFC1570 */
129 #define CPCODES_RESET_REQ	14	/* Reset-Request (CCP only) RFC1962 */
130 #define CPCODES_RESET_REP	15	/* Reset-Reply (CCP only) */
131 
132 static const struct tok cpcodes[] = {
133 	{CPCODES_VEXT,      "Vendor-Extension"}, /* RFC2153 */
134 	{CPCODES_CONF_REQ,  "Conf-Request"},
135         {CPCODES_CONF_ACK,  "Conf-Ack"},
136 	{CPCODES_CONF_NAK,  "Conf-Nack"},
137 	{CPCODES_CONF_REJ,  "Conf-Reject"},
138 	{CPCODES_TERM_REQ,  "Term-Request"},
139 	{CPCODES_TERM_ACK,  "Term-Ack"},
140 	{CPCODES_CODE_REJ,  "Code-Reject"},
141 	{CPCODES_PROT_REJ,  "Prot-Reject"},
142 	{CPCODES_ECHO_REQ,  "Echo-Request"},
143 	{CPCODES_ECHO_RPL,  "Echo-Reply"},
144 	{CPCODES_DISC_REQ,  "Disc-Req"},
145 	{CPCODES_ID,        "Ident"},            /* RFC1570 */
146 	{CPCODES_TIME_REM,  "Time-Rem"},         /* RFC1570 */
147 	{CPCODES_RESET_REQ, "Reset-Req"},        /* RFC1962 */
148 	{CPCODES_RESET_REP, "Reset-Ack"},        /* RFC1962 */
149         {0,                 NULL}
150 };
151 
152 /* LCP Config Options */
153 
154 #define LCPOPT_VEXT	0
155 #define LCPOPT_MRU	1
156 #define LCPOPT_ACCM	2
157 #define LCPOPT_AP	3
158 #define LCPOPT_QP	4
159 #define LCPOPT_MN	5
160 #define LCPOPT_DEP6	6
161 #define LCPOPT_PFC	7
162 #define LCPOPT_ACFC	8
163 #define LCPOPT_FCSALT	9
164 #define LCPOPT_SDP	10
165 #define LCPOPT_NUMMODE	11
166 #define LCPOPT_DEP12	12
167 #define LCPOPT_CBACK	13
168 #define LCPOPT_DEP14	14
169 #define LCPOPT_DEP15	15
170 #define LCPOPT_DEP16	16
171 #define LCPOPT_MLMRRU	17
172 #define LCPOPT_MLSSNHF	18
173 #define LCPOPT_MLED	19
174 #define LCPOPT_PROP	20
175 #define LCPOPT_DCEID	21
176 #define LCPOPT_MPP	22
177 #define LCPOPT_LD	23
178 #define LCPOPT_LCPAOPT	24
179 #define LCPOPT_COBS	25
180 #define LCPOPT_PE	26
181 #define LCPOPT_MLHF	27
182 #define LCPOPT_I18N	28
183 #define LCPOPT_SDLOS	29
184 #define LCPOPT_PPPMUX	30
185 
186 static const char *lcpconfopts[] = {
187 	"Vend-Ext",		/* (0) */
188 	"MRU",			/* (1) */
189 	"ACCM",			/* (2) */
190 	"Auth-Prot",		/* (3) */
191 	"Qual-Prot",		/* (4) */
192 	"Magic-Num",		/* (5) */
193 	"deprecated(6)",	/* used to be a Quality Protocol */
194 	"PFC",			/* (7) */
195 	"ACFC",			/* (8) */
196 	"FCS-Alt",		/* (9) */
197 	"SDP",			/* (10) */
198 	"Num-Mode",		/* (11) */
199 	"deprecated(12)",	/* used to be a Multi-Link-Procedure*/
200 	"Call-Back",		/* (13) */
201 	"deprecated(14)",	/* used to be a Connect-Time */
202 	"deprecated(15)",	/* used to be a Compound-Frames */
203 	"deprecated(16)",	/* used to be a Nominal-Data-Encap */
204 	"MRRU",			/* (17) */
205 	"12-Bit seq #",		/* (18) */
206 	"End-Disc",		/* (19) */
207 	"Proprietary",		/* (20) */
208 	"DCE-Id",		/* (21) */
209 	"MP+",			/* (22) */
210 	"Link-Disc",		/* (23) */
211 	"LCP-Auth-Opt",		/* (24) */
212 	"COBS",			/* (25) */
213 	"Prefix-elision",	/* (26) */
214 	"Multilink-header-Form",/* (27) */
215 	"I18N",			/* (28) */
216 	"SDL-over-SONET/SDH",	/* (29) */
217 	"PPP-Muxing",		/* (30) */
218 };
219 
220 #define NUM_LCPOPTS	(sizeof(lcpconfopts) / sizeof(lcpconfopts[0]))
221 
222 /* ECP - to be supported */
223 
224 /* CCP Config Options */
225 
226 #define CCPOPT_OUI	0	/* RFC1962 */
227 #define CCPOPT_PRED1	1	/* RFC1962 */
228 #define CCPOPT_PRED2	2	/* RFC1962 */
229 #define CCPOPT_PJUMP	3	/* RFC1962 */
230 /* 4-15 unassigned */
231 #define CCPOPT_HPPPC	16	/* RFC1962 */
232 #define CCPOPT_STACLZS	17	/* RFC1974 */
233 #define CCPOPT_MPPC	18	/* RFC2118 */
234 #define CCPOPT_GFZA	19	/* RFC1962 */
235 #define CCPOPT_V42BIS	20	/* RFC1962 */
236 #define CCPOPT_BSDCOMP	21	/* RFC1977 */
237 /* 22 unassigned */
238 #define CCPOPT_LZSDCP	23	/* RFC1967 */
239 #define CCPOPT_MVRCA	24	/* RFC1975 */
240 #define CCPOPT_DEC	25	/* RFC1976 */
241 #define CCPOPT_DEFLATE	26	/* RFC1979 */
242 /* 27-254 unassigned */
243 #define CCPOPT_RESV	255	/* RFC1962 */
244 
245 static const struct tok ccpconfopts_values[] = {
246         { CCPOPT_OUI, "OUI" },
247         { CCPOPT_PRED1, "Pred-1" },
248         { CCPOPT_PRED2, "Pred-2" },
249         { CCPOPT_PJUMP, "Puddle" },
250         { CCPOPT_HPPPC, "HP-PPC" },
251         { CCPOPT_STACLZS, "Stac-LZS" },
252         { CCPOPT_MPPC, "MPPC" },
253         { CCPOPT_GFZA, "Gand-FZA" },
254         { CCPOPT_V42BIS, "V.42bis" },
255         { CCPOPT_BSDCOMP, "BSD-Comp" },
256         { CCPOPT_LZSDCP, "LZS-DCP" },
257         { CCPOPT_MVRCA, "MVRCA" },
258         { CCPOPT_DEC, "DEC" },
259         { CCPOPT_DEFLATE, "Deflate" },
260         { CCPOPT_RESV, "Reserved"},
261         {0,                 NULL}
262 };
263 
264 /* BACP Config Options */
265 
266 #define BACPOPT_FPEER	1	/* RFC2125 */
267 
268 static const struct tok bacconfopts_values[] = {
269         { BACPOPT_FPEER, "Favored-Peer" },
270         {0,                 NULL}
271 };
272 
273 
274 /* SDCP - to be supported */
275 
276 /* IPCP Config Options */
277 #define IPCPOPT_2ADDR	1	/* RFC1172, RFC1332 (deprecated) */
278 #define IPCPOPT_IPCOMP	2	/* RFC1332 */
279 #define IPCPOPT_ADDR	3	/* RFC1332 */
280 #define IPCPOPT_MOBILE4	4	/* RFC2290 */
281 #define IPCPOPT_PRIDNS	129	/* RFC1877 */
282 #define IPCPOPT_PRINBNS	130	/* RFC1877 */
283 #define IPCPOPT_SECDNS	131	/* RFC1877 */
284 #define IPCPOPT_SECNBNS	132	/* RFC1877 */
285 
286 static const struct tok ipcpopt_values[] = {
287         { IPCPOPT_2ADDR, "IP-Addrs" },
288         { IPCPOPT_IPCOMP, "IP-Comp" },
289         { IPCPOPT_ADDR, "IP-Addr" },
290         { IPCPOPT_MOBILE4, "Home-Addr" },
291         { IPCPOPT_PRIDNS, "Pri-DNS" },
292         { IPCPOPT_PRINBNS, "Pri-NBNS" },
293         { IPCPOPT_SECDNS, "Sec-DNS" },
294         { IPCPOPT_SECNBNS, "Sec-NBNS" },
295 	{ 0,		  NULL }
296 };
297 
298 #define IPCPOPT_IPCOMP_HDRCOMP 0x61  /* rfc3544 */
299 #define IPCPOPT_IPCOMP_MINLEN    14
300 
301 static const struct tok ipcpopt_compproto_values[] = {
302         { PPP_VJC, "VJ-Comp" },
303         { IPCPOPT_IPCOMP_HDRCOMP, "IP Header Compression" },
304 	{ 0,		  NULL }
305 };
306 
307 static const struct tok ipcpopt_compproto_subopt_values[] = {
308         { 1, "RTP-Compression" },
309         { 2, "Enhanced RTP-Compression" },
310 	{ 0,		  NULL }
311 };
312 
313 /* IP6CP Config Options */
314 #define IP6CP_IFID      1
315 
316 static const struct tok ip6cpopt_values[] = {
317         { IP6CP_IFID, "Interface-ID" },
318 	{ 0,		  NULL }
319 };
320 
321 /* ATCP - to be supported */
322 /* OSINLCP - to be supported */
323 /* BVCP - to be supported */
324 /* BCP - to be supported */
325 /* IPXCP - to be supported */
326 /* MPLSCP - to be supported */
327 
328 /* Auth Algorithms */
329 
330 /* 0-4 Reserved (RFC1994) */
331 #define AUTHALG_CHAPMD5	5	/* RFC1994 */
332 #define AUTHALG_MSCHAP1	128	/* RFC2433 */
333 #define AUTHALG_MSCHAP2	129	/* RFC2795 */
334 
335 static const struct tok authalg_values[] = {
336         { AUTHALG_CHAPMD5, "MD5" },
337         { AUTHALG_MSCHAP1, "MS-CHAPv1" },
338         { AUTHALG_MSCHAP2, "MS-CHAPv2" },
339 	{ 0,		  NULL }
340 };
341 
342 /* FCS Alternatives - to be supported */
343 
344 /* Multilink Endpoint Discriminator (RFC1717) */
345 #define MEDCLASS_NULL	0	/* Null Class */
346 #define MEDCLASS_LOCAL	1	/* Locally Assigned */
347 #define MEDCLASS_IPV4	2	/* Internet Protocol (IPv4) */
348 #define MEDCLASS_MAC	3	/* IEEE 802.1 global MAC address */
349 #define MEDCLASS_MNB	4	/* PPP Magic Number Block */
350 #define MEDCLASS_PSNDN	5	/* Public Switched Network Director Number */
351 
352 /* PPP LCP Callback */
353 #define CALLBACK_AUTH	0	/* Location determined by user auth */
354 #define CALLBACK_DSTR	1	/* Dialing string */
355 #define CALLBACK_LID	2	/* Location identifier */
356 #define CALLBACK_E164	3	/* E.164 number */
357 #define CALLBACK_X500	4	/* X.500 distinguished name */
358 #define CALLBACK_CBCP	6	/* Location is determined during CBCP nego */
359 
360 static const struct tok ppp_callback_values[] = {
361         { CALLBACK_AUTH, "UserAuth" },
362         { CALLBACK_DSTR, "DialString" },
363         { CALLBACK_LID, "LocalID" },
364         { CALLBACK_E164, "E.164" },
365         { CALLBACK_X500, "X.500" },
366         { CALLBACK_CBCP, "CBCP" },
367 	{ 0,		  NULL }
368 };
369 
370 /* CHAP */
371 
372 #define CHAP_CHAL	1
373 #define CHAP_RESP	2
374 #define CHAP_SUCC	3
375 #define CHAP_FAIL	4
376 
377 static const struct tok chapcode_values[] = {
378 	{ CHAP_CHAL, "Challenge" },
379 	{ CHAP_RESP, "Response" },
380 	{ CHAP_SUCC, "Success" },
381 	{ CHAP_FAIL, "Fail" },
382         { 0, NULL}
383 };
384 
385 /* PAP */
386 
387 #define PAP_AREQ	1
388 #define PAP_AACK	2
389 #define PAP_ANAK	3
390 
391 static const struct tok papcode_values[] = {
392         { PAP_AREQ, "Auth-Req" },
393         { PAP_AACK, "Auth-ACK" },
394         { PAP_ANAK, "Auth-NACK" },
395         { 0, NULL }
396 };
397 
398 /* BAP */
399 #define BAP_CALLREQ	1
400 #define BAP_CALLRES	2
401 #define BAP_CBREQ	3
402 #define BAP_CBRES	4
403 #define BAP_LDQREQ	5
404 #define BAP_LDQRES	6
405 #define BAP_CSIND	7
406 #define BAP_CSRES	8
407 
408 static u_int print_lcp_config_options(netdissect_options *, const u_char *p, u_int);
409 static u_int print_ipcp_config_options(netdissect_options *, const u_char *p, u_int);
410 static u_int print_ip6cp_config_options(netdissect_options *, const u_char *p, u_int);
411 static u_int print_ccp_config_options(netdissect_options *, const u_char *p, u_int);
412 static u_int print_bacp_config_options(netdissect_options *, const u_char *p, u_int);
413 static void handle_ppp(netdissect_options *, u_int proto, const u_char *p, u_int length);
414 
415 /* generic Control Protocol (e.g. LCP, IPCP, CCP, etc.) handler */
416 static void
417 handle_ctrl_proto(netdissect_options *ndo,
418                   u_int proto, const u_char *pptr, u_int length)
419 {
420 	const char *typestr;
421 	u_int code, len;
422 	u_int (*pfunc)(netdissect_options *, const u_char *, u_int);
423 	u_int tlen, advance;
424         const u_char *tptr;
425 
426         tptr=pptr;
427 
428         typestr = tok2str(ppptype2str, "unknown ctrl-proto (0x%04x)", proto);
429 	ND_PRINT("%s, ", typestr);
430 
431 	if (length < 4) /* FIXME weak boundary checking */
432 		goto trunc;
433 	ND_TCHECK_2(tptr);
434 
435 	code = GET_U_1(tptr);
436 	tptr++;
437 
438 	ND_PRINT("%s (0x%02x), id %u, length %u",
439 	          tok2str(cpcodes, "Unknown Opcode",code),
440 	          code,
441 	          GET_U_1(tptr), /* ID */
442 	          length + 2);
443 	tptr++;
444 
445 	if (!ndo->ndo_vflag)
446 		return;
447 
448 	len = GET_BE_U_2(tptr);
449 	tptr += 2;
450 
451 	if (len < 4) {
452 		ND_PRINT("\n\tencoded length %u (< 4))", len);
453 		return;
454 	}
455 
456 	if (len > length) {
457 		ND_PRINT("\n\tencoded length %u (> packet length %u))", len, length);
458 		return;
459 	}
460 	length = len;
461 
462 	ND_PRINT("\n\tencoded length %u (=Option(s) length %u)", len, len - 4);
463 
464 	if (length == 4)
465 		return;    /* there may be a NULL confreq etc. */
466 
467 	if (ndo->ndo_vflag > 1)
468 		print_unknown_data(ndo, pptr - 2, "\n\t", 6);
469 
470 
471 	switch (code) {
472 	case CPCODES_VEXT:
473 		if (length < 11)
474 			break;
475 		ND_PRINT("\n\t  Magic-Num 0x%08x", GET_BE_U_4(tptr));
476 		tptr += 4;
477 		ND_PRINT(" Vendor: %s (%u)",
478                        tok2str(oui_values,"Unknown",GET_BE_U_3(tptr)),
479                        GET_BE_U_3(tptr));
480 		/* XXX: need to decode Kind and Value(s)? */
481 		break;
482 	case CPCODES_CONF_REQ:
483 	case CPCODES_CONF_ACK:
484 	case CPCODES_CONF_NAK:
485 	case CPCODES_CONF_REJ:
486 		tlen = len - 4;	/* Code(1), Identifier(1) and Length(2) */
487 		do {
488 			switch (proto) {
489 			case PPP_LCP:
490 				pfunc = print_lcp_config_options;
491 				break;
492 			case PPP_IPCP:
493 				pfunc = print_ipcp_config_options;
494 				break;
495 			case PPP_IPV6CP:
496 				pfunc = print_ip6cp_config_options;
497 				break;
498 			case PPP_CCP:
499 				pfunc = print_ccp_config_options;
500 				break;
501 			case PPP_BACP:
502 				pfunc = print_bacp_config_options;
503 				break;
504 			default:
505 				/*
506 				 * No print routine for the options for
507 				 * this protocol.
508 				 */
509 				pfunc = NULL;
510 				break;
511 			}
512 
513 			if (pfunc == NULL) /* catch the above null pointer if unknown CP */
514 				break;
515 
516 			if ((advance = (*pfunc)(ndo, tptr, len)) == 0)
517 				break;
518 			if (tlen < advance) {
519 				ND_PRINT(" [remaining options length %u < %u]",
520 					 tlen, advance);
521 				nd_print_invalid(ndo);
522 				break;
523 			}
524 			tlen -= advance;
525 			tptr += advance;
526 		} while (tlen != 0);
527 		break;
528 
529 	case CPCODES_TERM_REQ:
530 	case CPCODES_TERM_ACK:
531 		/* XXX: need to decode Data? */
532 		break;
533 	case CPCODES_CODE_REJ:
534 		/* XXX: need to decode Rejected-Packet? */
535 		break;
536 	case CPCODES_PROT_REJ:
537 		if (length < 6)
538 			break;
539 		ND_PRINT("\n\t  Rejected %s Protocol (0x%04x)",
540 		       tok2str(ppptype2str,"unknown", GET_BE_U_2(tptr)),
541 		       GET_BE_U_2(tptr));
542 		/* XXX: need to decode Rejected-Information? - hexdump for now */
543 		if (len > 6) {
544 			ND_PRINT("\n\t  Rejected Packet");
545 			print_unknown_data(ndo, tptr + 2, "\n\t    ", len - 2);
546 		}
547 		break;
548 	case CPCODES_ECHO_REQ:
549 	case CPCODES_ECHO_RPL:
550 	case CPCODES_DISC_REQ:
551 		if (length < 8)
552 			break;
553 		ND_PRINT("\n\t  Magic-Num 0x%08x", GET_BE_U_4(tptr));
554 		/* XXX: need to decode Data? - hexdump for now */
555 		if (len > 8) {
556 			ND_PRINT("\n\t  -----trailing data-----");
557 			ND_TCHECK_LEN(tptr + 4, len - 8);
558 			print_unknown_data(ndo, tptr + 4, "\n\t  ", len - 8);
559 		}
560 		break;
561 	case CPCODES_ID:
562 		if (length < 8)
563 			break;
564 		ND_PRINT("\n\t  Magic-Num 0x%08x", GET_BE_U_4(tptr));
565 		/* RFC 1661 says this is intended to be human readable */
566 		if (len > 8) {
567 			ND_PRINT("\n\t  Message\n\t    ");
568 			if (nd_printn(ndo, tptr + 4, len - 4, ndo->ndo_snapend))
569 				goto trunc;
570 		}
571 		break;
572 	case CPCODES_TIME_REM:
573 		if (length < 12)
574 			break;
575 		ND_PRINT("\n\t  Magic-Num 0x%08x", GET_BE_U_4(tptr));
576 		ND_PRINT(", Seconds-Remaining %us", GET_BE_U_4(tptr + 4));
577 		/* XXX: need to decode Message? */
578 		break;
579 	default:
580 		/* XXX this is dirty but we do not get the
581 		 * original pointer passed to the begin
582 		 * the PPP packet */
583 		if (ndo->ndo_vflag <= 1)
584 			print_unknown_data(ndo, pptr - 2, "\n\t  ", length + 2);
585 		break;
586 	}
587 	return;
588 
589 trunc:
590 	ND_PRINT("[|%s]", typestr);
591 }
592 
593 /* LCP config options */
594 static u_int
595 print_lcp_config_options(netdissect_options *ndo,
596                          const u_char *p, u_int length)
597 {
598 	u_int opt, len;
599 
600 	if (length < 2)
601 		return 0;
602 	ND_TCHECK_2(p);
603 	opt = GET_U_1(p);
604 	len = GET_U_1(p + 1);
605 	if (length < len)
606 		return 0;
607 	if (len < 2) {
608 		if (opt < NUM_LCPOPTS)
609 			ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
610 			          lcpconfopts[opt], opt, len);
611 		else
612 			ND_PRINT("\n\tunknown LCP option 0x%02x", opt);
613 		return 0;
614 	}
615 	if (opt < NUM_LCPOPTS)
616 		ND_PRINT("\n\t  %s Option (0x%02x), length %u", lcpconfopts[opt], opt, len);
617 	else {
618 		ND_PRINT("\n\tunknown LCP option 0x%02x", opt);
619 		return len;
620 	}
621 
622 	switch (opt) {
623 	case LCPOPT_VEXT:
624 		if (len < 6) {
625 			ND_PRINT(" (length bogus, should be >= 6)");
626 			return len;
627 		}
628 		ND_PRINT(": Vendor: %s (%u)",
629 			tok2str(oui_values,"Unknown",GET_BE_U_3(p + 2)),
630 			GET_BE_U_3(p + 2));
631 #if 0
632 		ND_PRINT(", kind: 0x%02x", GET_U_1(p + 5));
633 		ND_PRINT(", Value: 0x");
634 		for (i = 0; i < len - 6; i++) {
635 			ND_PRINT("%02x", GET_U_1(p + 6 + i));
636 		}
637 #endif
638 		break;
639 	case LCPOPT_MRU:
640 		if (len != 4) {
641 			ND_PRINT(" (length bogus, should be = 4)");
642 			return len;
643 		}
644 		ND_PRINT(": %u", GET_BE_U_2(p + 2));
645 		break;
646 	case LCPOPT_ACCM:
647 		if (len != 6) {
648 			ND_PRINT(" (length bogus, should be = 6)");
649 			return len;
650 		}
651 		ND_PRINT(": 0x%08x", GET_BE_U_4(p + 2));
652 		break;
653 	case LCPOPT_AP:
654 		if (len < 4) {
655 			ND_PRINT(" (length bogus, should be >= 4)");
656 			return len;
657 		}
658 		ND_PRINT(": %s",
659 			 tok2str(ppptype2str, "Unknown Auth Proto (0x04x)", GET_BE_U_2(p + 2)));
660 
661 		switch (GET_BE_U_2(p + 2)) {
662 		case PPP_CHAP:
663 			ND_PRINT(", %s",
664 				 tok2str(authalg_values, "Unknown Auth Alg %u", GET_U_1(p + 4)));
665 			break;
666 		case PPP_PAP: /* fall through */
667 		case PPP_EAP:
668 		case PPP_SPAP:
669 		case PPP_SPAP_OLD:
670                         break;
671 		default:
672 			print_unknown_data(ndo, p, "\n\t", len);
673 		}
674 		break;
675 	case LCPOPT_QP:
676 		if (len < 4) {
677 			ND_PRINT(" (length bogus, should be >= 4)");
678 			return 0;
679 		}
680 		if (GET_BE_U_2(p + 2) == PPP_LQM)
681 			ND_PRINT(": LQR");
682 		else
683 			ND_PRINT(": unknown");
684 		break;
685 	case LCPOPT_MN:
686 		if (len != 6) {
687 			ND_PRINT(" (length bogus, should be = 6)");
688 			return 0;
689 		}
690 		ND_PRINT(": 0x%08x", GET_BE_U_4(p + 2));
691 		break;
692 	case LCPOPT_PFC:
693 		break;
694 	case LCPOPT_ACFC:
695 		break;
696 	case LCPOPT_LD:
697 		if (len != 4) {
698 			ND_PRINT(" (length bogus, should be = 4)");
699 			return 0;
700 		}
701 		ND_PRINT(": 0x%04x", GET_BE_U_2(p + 2));
702 		break;
703 	case LCPOPT_CBACK:
704 		if (len < 3) {
705 			ND_PRINT(" (length bogus, should be >= 3)");
706 			return 0;
707 		}
708 		ND_PRINT(": Callback Operation %s (%u)",
709                        tok2str(ppp_callback_values, "Unknown", GET_U_1(p + 2)),
710                        GET_U_1(p + 2));
711 		break;
712 	case LCPOPT_MLMRRU:
713 		if (len != 4) {
714 			ND_PRINT(" (length bogus, should be = 4)");
715 			return 0;
716 		}
717 		ND_PRINT(": %u", GET_BE_U_2(p + 2));
718 		break;
719 	case LCPOPT_MLED:
720 		if (len < 3) {
721 			ND_PRINT(" (length bogus, should be >= 3)");
722 			return 0;
723 		}
724 		switch (GET_U_1(p + 2)) {		/* class */
725 		case MEDCLASS_NULL:
726 			ND_PRINT(": Null");
727 			break;
728 		case MEDCLASS_LOCAL:
729 			ND_PRINT(": Local"); /* XXX */
730 			break;
731 		case MEDCLASS_IPV4:
732 			if (len != 7) {
733 				ND_PRINT(" (length bogus, should be = 7)");
734 				return 0;
735 			}
736 			ND_PRINT(": IPv4 %s", GET_IPADDR_STRING(p + 3));
737 			break;
738 		case MEDCLASS_MAC:
739 			if (len != 9) {
740 				ND_PRINT(" (length bogus, should be = 9)");
741 				return 0;
742 			}
743 			ND_PRINT(": MAC %s", GET_ETHERADDR_STRING(p + 3));
744 			break;
745 		case MEDCLASS_MNB:
746 			ND_PRINT(": Magic-Num-Block"); /* XXX */
747 			break;
748 		case MEDCLASS_PSNDN:
749 			ND_PRINT(": PSNDN"); /* XXX */
750 			break;
751 		default:
752 			ND_PRINT(": Unknown class %u", GET_U_1(p + 2));
753 			break;
754 		}
755 		break;
756 
757 /* XXX: to be supported */
758 #if 0
759 	case LCPOPT_DEP6:
760 	case LCPOPT_FCSALT:
761 	case LCPOPT_SDP:
762 	case LCPOPT_NUMMODE:
763 	case LCPOPT_DEP12:
764 	case LCPOPT_DEP14:
765 	case LCPOPT_DEP15:
766 	case LCPOPT_DEP16:
767         case LCPOPT_MLSSNHF:
768 	case LCPOPT_PROP:
769 	case LCPOPT_DCEID:
770 	case LCPOPT_MPP:
771 	case LCPOPT_LCPAOPT:
772 	case LCPOPT_COBS:
773 	case LCPOPT_PE:
774 	case LCPOPT_MLHF:
775 	case LCPOPT_I18N:
776 	case LCPOPT_SDLOS:
777 	case LCPOPT_PPPMUX:
778 		break;
779 #endif
780 	default:
781 		/*
782 		 * Unknown option; dump it as raw bytes now if we're
783 		 * not going to do so below.
784 		 */
785 		if (ndo->ndo_vflag < 2)
786 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
787 		break;
788 	}
789 
790 	if (ndo->ndo_vflag > 1)
791 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
792 
793 	return len;
794 
795 trunc:
796 	ND_PRINT("[|lcp]");
797 	return 0;
798 }
799 
800 /* ML-PPP*/
801 static const struct tok ppp_ml_flag_values[] = {
802     { 0x80, "begin" },
803     { 0x40, "end" },
804     { 0, NULL }
805 };
806 
807 static void
808 handle_mlppp(netdissect_options *ndo,
809              const u_char *p, u_int length)
810 {
811     if (!ndo->ndo_eflag)
812         ND_PRINT("MLPPP, ");
813 
814     if (length < 2) {
815         ND_PRINT("[|mlppp]");
816         return;
817     }
818     if (!ND_TTEST_2(p)) {
819         ND_PRINT("[|mlppp]");
820         return;
821     }
822 
823     ND_PRINT("seq 0x%03x, Flags [%s], length %u",
824            (GET_BE_U_2(p))&0x0fff,
825            /* only support 12-Bit sequence space for now */
826            bittok2str(ppp_ml_flag_values, "none", GET_U_1(p) & 0xc0),
827            length);
828 }
829 
830 /* CHAP */
831 static void
832 handle_chap(netdissect_options *ndo,
833             const u_char *p, u_int length)
834 {
835 	u_int code, len;
836 	u_int val_size, name_size, msg_size;
837 	const u_char *p0;
838 	u_int i;
839 
840 	p0 = p;
841 	if (length < 1) {
842 		ND_PRINT("[|chap]");
843 		return;
844 	} else if (length < 4) {
845 		ND_PRINT("[|chap 0x%02x]", GET_U_1(p));
846 		return;
847 	}
848 
849 	code = GET_U_1(p);
850 	ND_PRINT("CHAP, %s (0x%02x)",
851                tok2str(chapcode_values,"unknown",code),
852                code);
853 	p++;
854 
855 	ND_PRINT(", id %u", GET_U_1(p));	/* ID */
856 	p++;
857 
858 	len = GET_BE_U_2(p);
859 	p += 2;
860 
861 	/*
862 	 * Note that this is a generic CHAP decoding routine. Since we
863 	 * don't know which flavor of CHAP (i.e. CHAP-MD5, MS-CHAPv1,
864 	 * MS-CHAPv2) is used at this point, we can't decode packet
865 	 * specifically to each algorithms. Instead, we simply decode
866 	 * the GCD (Greatest Common Denominator) for all algorithms.
867 	 */
868 	switch (code) {
869 	case CHAP_CHAL:
870 	case CHAP_RESP:
871 		if (length - (p - p0) < 1)
872 			return;
873 		val_size = GET_U_1(p);	/* value size */
874 		p++;
875 		if (length - (p - p0) < val_size)
876 			return;
877 		ND_PRINT(", Value ");
878 		for (i = 0; i < val_size; i++) {
879 			ND_PRINT("%02x", GET_U_1(p));
880 			p++;
881 		}
882 		name_size = len - (u_int)(p - p0);
883 		ND_PRINT(", Name ");
884 		for (i = 0; i < name_size; i++) {
885 			fn_print_char(ndo, GET_U_1(p));
886 			p++;
887 		}
888 		break;
889 	case CHAP_SUCC:
890 	case CHAP_FAIL:
891 		msg_size = len - (u_int)(p - p0);
892 		ND_PRINT(", Msg ");
893 		for (i = 0; i< msg_size; i++) {
894 			fn_print_char(ndo, GET_U_1(p));
895 			p++;
896 		}
897 		break;
898 	}
899 }
900 
901 /* PAP (see RFC 1334) */
902 static void
903 handle_pap(netdissect_options *ndo,
904            const u_char *p, u_int length)
905 {
906 	u_int code, len;
907 	u_int peerid_len, passwd_len, msg_len;
908 	const u_char *p0;
909 	u_int i;
910 
911 	p0 = p;
912 	if (length < 1) {
913 		ND_PRINT("[|pap]");
914 		return;
915 	} else if (length < 4) {
916 		ND_PRINT("[|pap 0x%02x]", GET_U_1(p));
917 		return;
918 	}
919 
920 	code = GET_U_1(p);
921 	ND_PRINT("PAP, %s (0x%02x)",
922 	          tok2str(papcode_values, "unknown", code),
923 	          code);
924 	p++;
925 
926 	ND_PRINT(", id %u", GET_U_1(p));	/* ID */
927 	p++;
928 
929 	len = GET_BE_U_2(p);
930 	p += 2;
931 
932 	if (len > length) {
933 		ND_PRINT(", length %u > packet size", len);
934 		return;
935 	}
936 	length = len;
937 	if (length < (size_t)(p - p0)) {
938 		ND_PRINT(", length %u < PAP header length", length);
939 		return;
940 	}
941 
942 	switch (code) {
943 	case PAP_AREQ:
944 		/* A valid Authenticate-Request is 6 or more octets long. */
945 		if (len < 6)
946 			goto trunc;
947 		if (length - (p - p0) < 1)
948 			return;
949 		peerid_len = GET_U_1(p);	/* Peer-ID Length */
950 		p++;
951 		if (length - (p - p0) < peerid_len)
952 			return;
953 		ND_PRINT(", Peer ");
954 		for (i = 0; i < peerid_len; i++) {
955 			fn_print_char(ndo, GET_U_1(p));
956 			p++;
957 		}
958 
959 		if (length - (p - p0) < 1)
960 			return;
961 		passwd_len = GET_U_1(p);	/* Password Length */
962 		p++;
963 		if (length - (p - p0) < passwd_len)
964 			return;
965 		ND_PRINT(", Name ");
966 		for (i = 0; i < passwd_len; i++) {
967 			fn_print_char(ndo, GET_U_1(p));
968 			p++;
969 		}
970 		break;
971 	case PAP_AACK:
972 	case PAP_ANAK:
973 		/* Although some implementations ignore truncation at
974 		 * this point and at least one generates a truncated
975 		 * packet, RFC 1334 section 2.2.2 clearly states that
976 		 * both AACK and ANAK are at least 5 bytes long.
977 		 */
978 		if (len < 5)
979 			goto trunc;
980 		if (length - (p - p0) < 1)
981 			return;
982 		msg_len = GET_U_1(p);	/* Msg-Length */
983 		p++;
984 		if (length - (p - p0) < msg_len)
985 			return;
986 		ND_PRINT(", Msg ");
987 		for (i = 0; i< msg_len; i++) {
988 			fn_print_char(ndo, GET_U_1(p));
989 			p++;
990 		}
991 		break;
992 	}
993 	return;
994 
995 trunc:
996 	ND_PRINT("[|pap]");
997 }
998 
999 /* BAP */
1000 static void
1001 handle_bap(netdissect_options *ndo _U_,
1002            const u_char *p _U_, u_int length _U_)
1003 {
1004 	/* XXX: to be supported!! */
1005 }
1006 
1007 
1008 /* IPCP config options */
1009 static u_int
1010 print_ipcp_config_options(netdissect_options *ndo,
1011                           const u_char *p, u_int length)
1012 {
1013 	u_int opt, len;
1014         u_int compproto, ipcomp_subopttotallen, ipcomp_subopt, ipcomp_suboptlen;
1015 
1016 	if (length < 2)
1017 		return 0;
1018 	ND_TCHECK_2(p);
1019 	opt = GET_U_1(p);
1020 	len = GET_U_1(p + 1);
1021 	if (length < len)
1022 		return 0;
1023 	if (len < 2) {
1024 		ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
1025 		       tok2str(ipcpopt_values,"unknown",opt),
1026 		       opt,
1027 		       len);
1028 		return 0;
1029 	}
1030 
1031 	ND_PRINT("\n\t  %s Option (0x%02x), length %u",
1032 	       tok2str(ipcpopt_values,"unknown",opt),
1033 	       opt,
1034 	       len);
1035 
1036 	switch (opt) {
1037 	case IPCPOPT_2ADDR:		/* deprecated */
1038 		if (len != 10) {
1039 			ND_PRINT(" (length bogus, should be = 10)");
1040 			return len;
1041 		}
1042 		ND_PRINT(": src %s, dst %s",
1043 		       GET_IPADDR_STRING(p + 2),
1044 		       GET_IPADDR_STRING(p + 6));
1045 		break;
1046 	case IPCPOPT_IPCOMP:
1047 		if (len < 4) {
1048 			ND_PRINT(" (length bogus, should be >= 4)");
1049 			return 0;
1050 		}
1051 		compproto = GET_BE_U_2(p + 2);
1052 
1053 		ND_PRINT(": %s (0x%02x):",
1054 		          tok2str(ipcpopt_compproto_values, "Unknown", compproto),
1055 		          compproto);
1056 
1057 		switch (compproto) {
1058                 case PPP_VJC:
1059 			/* XXX: VJ-Comp parameters should be decoded */
1060                         break;
1061                 case IPCPOPT_IPCOMP_HDRCOMP:
1062                         if (len < IPCPOPT_IPCOMP_MINLEN) {
1063                                 ND_PRINT(" (length bogus, should be >= %u)",
1064                                          IPCPOPT_IPCOMP_MINLEN);
1065                                 return 0;
1066                         }
1067 
1068                         ND_TCHECK_LEN(p + 2, IPCPOPT_IPCOMP_MINLEN);
1069                         ND_PRINT("\n\t    TCP Space %u, non-TCP Space %u"
1070                                ", maxPeriod %u, maxTime %u, maxHdr %u",
1071                                GET_BE_U_2(p + 4),
1072                                GET_BE_U_2(p + 6),
1073                                GET_BE_U_2(p + 8),
1074                                GET_BE_U_2(p + 10),
1075                                GET_BE_U_2(p + 12));
1076 
1077                         /* suboptions present ? */
1078                         if (len > IPCPOPT_IPCOMP_MINLEN) {
1079                                 ipcomp_subopttotallen = len - IPCPOPT_IPCOMP_MINLEN;
1080                                 p += IPCPOPT_IPCOMP_MINLEN;
1081 
1082                                 ND_PRINT("\n\t      Suboptions, length %u", ipcomp_subopttotallen);
1083 
1084                                 while (ipcomp_subopttotallen >= 2) {
1085                                         ND_TCHECK_2(p);
1086                                         ipcomp_subopt = GET_U_1(p);
1087                                         ipcomp_suboptlen = GET_U_1(p + 1);
1088 
1089                                         /* sanity check */
1090                                         if (ipcomp_subopt == 0 ||
1091                                             ipcomp_suboptlen == 0 )
1092                                                 break;
1093 
1094                                         /* XXX: just display the suboptions for now */
1095                                         ND_PRINT("\n\t\t%s Suboption #%u, length %u",
1096                                                tok2str(ipcpopt_compproto_subopt_values,
1097                                                        "Unknown",
1098                                                        ipcomp_subopt),
1099                                                ipcomp_subopt,
1100                                                ipcomp_suboptlen);
1101                                         if (ipcomp_subopttotallen < ipcomp_suboptlen) {
1102                                                 ND_PRINT(" [remaining suboptions length %u < %u]",
1103                                                          ipcomp_subopttotallen, ipcomp_suboptlen);
1104                                                 nd_print_invalid(ndo);
1105                                                 break;
1106                                         }
1107                                         ipcomp_subopttotallen -= ipcomp_suboptlen;
1108                                         p += ipcomp_suboptlen;
1109                                 }
1110                         }
1111                         break;
1112                 default:
1113                         break;
1114 		}
1115 		break;
1116 
1117 	case IPCPOPT_ADDR:     /* those options share the same format - fall through */
1118 	case IPCPOPT_MOBILE4:
1119 	case IPCPOPT_PRIDNS:
1120 	case IPCPOPT_PRINBNS:
1121 	case IPCPOPT_SECDNS:
1122 	case IPCPOPT_SECNBNS:
1123 		if (len != 6) {
1124 			ND_PRINT(" (length bogus, should be = 6)");
1125 			return 0;
1126 		}
1127 		ND_PRINT(": %s", GET_IPADDR_STRING(p + 2));
1128 		break;
1129 	default:
1130 		/*
1131 		 * Unknown option; dump it as raw bytes now if we're
1132 		 * not going to do so below.
1133 		 */
1134 		if (ndo->ndo_vflag < 2)
1135 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
1136 		break;
1137 	}
1138 	if (ndo->ndo_vflag > 1 && ND_TTEST_LEN(p + 2, len - 2))
1139 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
1140 	return len;
1141 
1142 trunc:
1143 	ND_PRINT("[|ipcp]");
1144 	return 0;
1145 }
1146 
1147 /* IP6CP config options */
1148 static u_int
1149 print_ip6cp_config_options(netdissect_options *ndo,
1150                            const u_char *p, u_int length)
1151 {
1152 	u_int opt, len;
1153 
1154 	if (length < 2)
1155 		return 0;
1156 	ND_TCHECK_2(p);
1157 	opt = GET_U_1(p);
1158 	len = GET_U_1(p + 1);
1159 	if (length < len)
1160 		return 0;
1161 	if (len < 2) {
1162 		ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
1163 		       tok2str(ip6cpopt_values,"unknown",opt),
1164 		       opt,
1165 		       len);
1166 		return 0;
1167 	}
1168 
1169 	ND_PRINT("\n\t  %s Option (0x%02x), length %u",
1170 	       tok2str(ip6cpopt_values,"unknown",opt),
1171 	       opt,
1172 	       len);
1173 
1174 	switch (opt) {
1175 	case IP6CP_IFID:
1176 		if (len != 10) {
1177 			ND_PRINT(" (length bogus, should be = 10)");
1178 			return len;
1179 		}
1180 		ND_TCHECK_8(p + 2);
1181 		ND_PRINT(": %04x:%04x:%04x:%04x",
1182 		       GET_BE_U_2(p + 2),
1183 		       GET_BE_U_2(p + 4),
1184 		       GET_BE_U_2(p + 6),
1185 		       GET_BE_U_2(p + 8));
1186 		break;
1187 	default:
1188 		/*
1189 		 * Unknown option; dump it as raw bytes now if we're
1190 		 * not going to do so below.
1191 		 */
1192 		if (ndo->ndo_vflag < 2)
1193 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
1194 		break;
1195 	}
1196 	if (ndo->ndo_vflag > 1)
1197 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
1198 
1199 	return len;
1200 
1201 trunc:
1202 	ND_PRINT("[|ip6cp]");
1203 	return 0;
1204 }
1205 
1206 
1207 /* CCP config options */
1208 static u_int
1209 print_ccp_config_options(netdissect_options *ndo,
1210                          const u_char *p, u_int length)
1211 {
1212 	u_int opt, len;
1213 
1214 	if (length < 2)
1215 		return 0;
1216 	ND_TCHECK_2(p);
1217 	opt = GET_U_1(p);
1218 	len = GET_U_1(p + 1);
1219 	if (length < len)
1220 		return 0;
1221 	if (len < 2) {
1222 		ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
1223 		          tok2str(ccpconfopts_values, "Unknown", opt),
1224 		          opt,
1225 		          len);
1226 		return 0;
1227 	}
1228 
1229 	ND_PRINT("\n\t  %s Option (0x%02x), length %u",
1230 	          tok2str(ccpconfopts_values, "Unknown", opt),
1231 	          opt,
1232 	          len);
1233 
1234 	switch (opt) {
1235 	case CCPOPT_BSDCOMP:
1236 		if (len < 3) {
1237 			ND_PRINT(" (length bogus, should be >= 3)");
1238 			return len;
1239 		}
1240 		ND_PRINT(": Version: %u, Dictionary Bits: %u",
1241 			GET_U_1(p + 2) >> 5,
1242 			GET_U_1(p + 2) & 0x1f);
1243 		break;
1244 	case CCPOPT_MVRCA:
1245 		if (len < 4) {
1246 			ND_PRINT(" (length bogus, should be >= 4)");
1247 			return len;
1248 		}
1249 		ND_PRINT(": Features: %u, PxP: %s, History: %u, #CTX-ID: %u",
1250 				(GET_U_1(p + 2) & 0xc0) >> 6,
1251 				(GET_U_1(p + 2) & 0x20) ? "Enabled" : "Disabled",
1252 				GET_U_1(p + 2) & 0x1f,
1253 				GET_U_1(p + 3));
1254 		break;
1255 	case CCPOPT_DEFLATE:
1256 		if (len < 4) {
1257 			ND_PRINT(" (length bogus, should be >= 4)");
1258 			return len;
1259 		}
1260 		ND_PRINT(": Window: %uK, Method: %s (0x%x), MBZ: %u, CHK: %u",
1261 			(GET_U_1(p + 2) & 0xf0) >> 4,
1262 			((GET_U_1(p + 2) & 0x0f) == 8) ? "zlib" : "unknown",
1263 			GET_U_1(p + 2) & 0x0f,
1264 			(GET_U_1(p + 3) & 0xfc) >> 2,
1265 			GET_U_1(p + 3) & 0x03);
1266 		break;
1267 
1268 /* XXX: to be supported */
1269 #if 0
1270 	case CCPOPT_OUI:
1271 	case CCPOPT_PRED1:
1272 	case CCPOPT_PRED2:
1273 	case CCPOPT_PJUMP:
1274 	case CCPOPT_HPPPC:
1275 	case CCPOPT_STACLZS:
1276 	case CCPOPT_MPPC:
1277 	case CCPOPT_GFZA:
1278 	case CCPOPT_V42BIS:
1279 	case CCPOPT_LZSDCP:
1280 	case CCPOPT_DEC:
1281 	case CCPOPT_RESV:
1282 		break;
1283 #endif
1284 	default:
1285 		/*
1286 		 * Unknown option; dump it as raw bytes now if we're
1287 		 * not going to do so below.
1288 		 */
1289 		if (ndo->ndo_vflag < 2)
1290 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
1291 		break;
1292 	}
1293 	if (ndo->ndo_vflag > 1)
1294 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
1295 
1296 	return len;
1297 
1298 trunc:
1299 	ND_PRINT("[|ccp]");
1300 	return 0;
1301 }
1302 
1303 /* BACP config options */
1304 static u_int
1305 print_bacp_config_options(netdissect_options *ndo,
1306                           const u_char *p, u_int length)
1307 {
1308 	u_int opt, len;
1309 
1310 	if (length < 2)
1311 		return 0;
1312 	ND_TCHECK_2(p);
1313 	opt = GET_U_1(p);
1314 	len = GET_U_1(p + 1);
1315 	if (length < len)
1316 		return 0;
1317 	if (len < 2) {
1318 		ND_PRINT("\n\t  %s Option (0x%02x), length %u (length bogus, should be >= 2)",
1319 		          tok2str(bacconfopts_values, "Unknown", opt),
1320 		          opt,
1321 		          len);
1322 		return 0;
1323 	}
1324 
1325 	ND_PRINT("\n\t  %s Option (0x%02x), length %u",
1326 	          tok2str(bacconfopts_values, "Unknown", opt),
1327 	          opt,
1328 	          len);
1329 
1330 	switch (opt) {
1331 	case BACPOPT_FPEER:
1332 		if (len != 6) {
1333 			ND_PRINT(" (length bogus, should be = 6)");
1334 			return len;
1335 		}
1336 		ND_PRINT(": Magic-Num 0x%08x", GET_BE_U_4(p + 2));
1337 		break;
1338 	default:
1339 		/*
1340 		 * Unknown option; dump it as raw bytes now if we're
1341 		 * not going to do so below.
1342 		 */
1343 		if (ndo->ndo_vflag < 2)
1344 			print_unknown_data(ndo, p + 2, "\n\t    ", len - 2);
1345 		break;
1346 	}
1347 	if (ndo->ndo_vflag > 1)
1348 		print_unknown_data(ndo, p + 2, "\n\t    ", len - 2); /* exclude TLV header */
1349 
1350 	return len;
1351 
1352 trunc:
1353 	ND_PRINT("[|bacp]");
1354 	return 0;
1355 }
1356 
1357 /*
1358  * Un-escape RFC 1662 PPP in HDLC-like framing, with octet escapes.
1359  * The length argument is the on-the-wire length, not the captured
1360  * length; we can only un-escape the captured part.
1361  */
1362 static void
1363 ppp_hdlc(netdissect_options *ndo,
1364          const u_char *p, u_int length)
1365 {
1366 	u_int caplen = ND_BYTES_AVAILABLE_AFTER(p);
1367 	u_char *b, *t, c;
1368 	const u_char *s;
1369 	u_int i, proto;
1370 
1371 	if (caplen == 0)
1372 		return;
1373 
1374         if (length == 0)
1375                 return;
1376 
1377 	b = (u_char *)malloc(caplen);
1378 	if (b == NULL) {
1379 		(*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
1380 			"%s: malloc", __func__);
1381 	}
1382 
1383 	/*
1384 	 * Unescape all the data into a temporary, private, buffer.
1385 	 * Do this so that we don't overwrite the original packet
1386 	 * contents.
1387 	 */
1388 	for (s = p, t = b, i = caplen; i != 0; i--) {
1389 		c = GET_U_1(s);
1390 		s++;
1391 		if (c == 0x7d) {
1392 			if (i <= 1)
1393 				break;
1394 			i--;
1395 			c = GET_U_1(s) ^ 0x20;
1396 			s++;
1397 		}
1398 		*t++ = c;
1399 	}
1400 
1401 	/*
1402 	 * Switch to the output buffer for dissection, and save it
1403 	 * on the buffer stack so it can be freed; our caller must
1404 	 * pop it when done.
1405 	 */
1406 	if (!nd_push_buffer(ndo, b, b, (u_int)(t - b))) {
1407 		free(b);
1408 		(*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
1409 			"%s: can't push buffer on buffer stack", __func__);
1410 	}
1411 	length = ND_BYTES_AVAILABLE_AFTER(b);
1412 
1413         /* now lets guess about the payload codepoint format */
1414         if (length < 1)
1415                 goto trunc;
1416         proto = GET_U_1(b); /* start with a one-octet codepoint guess */
1417 
1418         switch (proto) {
1419         case PPP_IP:
1420 		ip_print(ndo, b + 1, length - 1);
1421 		goto cleanup;
1422         case PPP_IPV6:
1423 		ip6_print(ndo, b + 1, length - 1);
1424 		goto cleanup;
1425         default: /* no luck - try next guess */
1426 		break;
1427         }
1428 
1429         if (length < 2)
1430                 goto trunc;
1431         proto = GET_BE_U_2(b); /* next guess - load two octets */
1432 
1433         switch (proto) {
1434         case (PPP_ADDRESS << 8 | PPP_CONTROL): /* looks like a PPP frame */
1435             if (length < 4)
1436                 goto trunc;
1437             proto = GET_BE_U_2(b + 2); /* load the PPP proto-id */
1438             if ((proto & 0xff00) == 0x7e00)
1439                 ND_PRINT("(protocol 0x%04x invalid)", proto);
1440             else
1441                 handle_ppp(ndo, proto, b + 4, length - 4);
1442             break;
1443         default: /* last guess - proto must be a PPP proto-id */
1444             if ((proto & 0xff00) == 0x7e00)
1445                 ND_PRINT("(protocol 0x%04x invalid)", proto);
1446             else
1447                 handle_ppp(ndo, proto, b + 2, length - 2);
1448             break;
1449         }
1450 
1451 cleanup:
1452 	nd_pop_packet_info(ndo);
1453         return;
1454 
1455 trunc:
1456 	nd_pop_packet_info(ndo);
1457 	nd_print_trunc(ndo);
1458 }
1459 
1460 
1461 /* PPP */
1462 static void
1463 handle_ppp(netdissect_options *ndo,
1464            u_int proto, const u_char *p, u_int length)
1465 {
1466 	if ((proto & 0xff00) == 0x7e00) { /* is this an escape code ? */
1467 		ppp_hdlc(ndo, p - 1, length);
1468 		return;
1469 	}
1470 
1471 	switch (proto) {
1472 	case PPP_LCP: /* fall through */
1473 	case PPP_IPCP:
1474 	case PPP_OSICP:
1475 	case PPP_MPLSCP:
1476 	case PPP_IPV6CP:
1477 	case PPP_CCP:
1478 	case PPP_BACP:
1479 		handle_ctrl_proto(ndo, proto, p, length);
1480 		break;
1481 	case PPP_ML:
1482 		handle_mlppp(ndo, p, length);
1483 		break;
1484 	case PPP_CHAP:
1485 		handle_chap(ndo, p, length);
1486 		break;
1487 	case PPP_PAP:
1488 		handle_pap(ndo, p, length);
1489 		break;
1490 	case PPP_BAP:		/* XXX: not yet completed */
1491 		handle_bap(ndo, p, length);
1492 		break;
1493 	case ETHERTYPE_IP:	/*XXX*/
1494         case PPP_VJNC:
1495 	case PPP_IP:
1496 		ip_print(ndo, p, length);
1497 		break;
1498 	case ETHERTYPE_IPV6:	/*XXX*/
1499 	case PPP_IPV6:
1500 		ip6_print(ndo, p, length);
1501 		break;
1502 	case ETHERTYPE_IPX:	/*XXX*/
1503 	case PPP_IPX:
1504 		ipx_print(ndo, p, length);
1505 		break;
1506 	case PPP_OSI:
1507 		isoclns_print(ndo, p, length);
1508 		break;
1509 	case PPP_MPLS_UCAST:
1510 	case PPP_MPLS_MCAST:
1511 		mpls_print(ndo, p, length);
1512 		break;
1513 	case PPP_COMP:
1514 		ND_PRINT("compressed PPP data");
1515 		break;
1516 	default:
1517 		ND_PRINT("%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto));
1518 		print_unknown_data(ndo, p, "\n\t", length);
1519 		break;
1520 	}
1521 }
1522 
1523 /* Standard PPP printer */
1524 u_int
1525 ppp_print(netdissect_options *ndo,
1526           const u_char *p, u_int length)
1527 {
1528 	u_int proto,ppp_header;
1529         u_int olen = length; /* _o_riginal length */
1530 	u_int hdr_len = 0;
1531 
1532 	ndo->ndo_protocol = "ppp";
1533 	/*
1534 	 * Here, we assume that p points to the Address and Control
1535 	 * field (if they present).
1536 	 */
1537 	if (length < 2)
1538 		goto trunc;
1539         ppp_header = GET_BE_U_2(p);
1540 
1541         switch(ppp_header) {
1542         case (PPP_PPPD_IN  << 8 | PPP_CONTROL):
1543             if (ndo->ndo_eflag) ND_PRINT("In  ");
1544             p += 2;
1545             length -= 2;
1546             hdr_len += 2;
1547             break;
1548         case (PPP_PPPD_OUT << 8 | PPP_CONTROL):
1549             if (ndo->ndo_eflag) ND_PRINT("Out ");
1550             p += 2;
1551             length -= 2;
1552             hdr_len += 2;
1553             break;
1554         case (PPP_ADDRESS << 8 | PPP_CONTROL):
1555             p += 2;			/* ACFC not used */
1556             length -= 2;
1557             hdr_len += 2;
1558             break;
1559 
1560         default:
1561             break;
1562         }
1563 
1564 	if (length < 2)
1565 		goto trunc;
1566 	if (GET_U_1(p) % 2) {
1567 		proto = GET_U_1(p);	/* PFC is used */
1568 		p++;
1569 		length--;
1570 		hdr_len++;
1571 	} else {
1572 		proto = GET_BE_U_2(p);
1573 		p += 2;
1574 		length -= 2;
1575 		hdr_len += 2;
1576 	}
1577 
1578 	if (ndo->ndo_eflag) {
1579 		const char *typestr;
1580 		typestr = tok2str(ppptype2str, "unknown", proto);
1581 		ND_PRINT("%s (0x%04x), length %u",
1582 		          typestr,
1583 		          proto,
1584 		          olen);
1585 		if (*typestr == 'u')	/* "unknown" */
1586 			return hdr_len;
1587 
1588 		ND_PRINT(": ");
1589 	}
1590 
1591 	handle_ppp(ndo, proto, p, length);
1592 	return (hdr_len);
1593 trunc:
1594 	nd_print_trunc(ndo);
1595 	return (0);
1596 }
1597 
1598 
1599 /* PPP I/F printer */
1600 void
1601 ppp_if_print(netdissect_options *ndo,
1602              const struct pcap_pkthdr *h, const u_char *p)
1603 {
1604 	u_int length = h->len;
1605 	u_int caplen = h->caplen;
1606 
1607 	ndo->ndo_protocol = "ppp";
1608 	if (caplen < PPP_HDRLEN) {
1609 		nd_print_trunc(ndo);
1610 		ndo->ndo_ll_hdr_len += caplen;
1611 		return;
1612 	}
1613 	ndo->ndo_ll_hdr_len += PPP_HDRLEN;
1614 
1615 #if 0
1616 	/*
1617 	 * XXX: seems to assume that there are 2 octets prepended to an
1618 	 * actual PPP frame. The 1st octet looks like Input/Output flag
1619 	 * while 2nd octet is unknown, at least to me
1620 	 * (mshindo@mshindo.net).
1621 	 *
1622 	 * That was what the original tcpdump code did.
1623 	 *
1624 	 * FreeBSD's "if_ppp.c" *does* set the first octet to 1 for outbound
1625 	 * packets and 0 for inbound packets - but only if the
1626 	 * protocol field has the 0x8000 bit set (i.e., it's a network
1627 	 * control protocol); it does so before running the packet through
1628 	 * "bpf_filter" to see if it should be discarded, and to see
1629 	 * if we should update the time we sent the most recent packet...
1630 	 *
1631 	 * ...but it puts the original address field back after doing
1632 	 * so.
1633 	 *
1634 	 * NetBSD's "if_ppp.c" doesn't set the first octet in that fashion.
1635 	 *
1636 	 * I don't know if any PPP implementation handed up to a BPF
1637 	 * device packets with the first octet being 1 for outbound and
1638 	 * 0 for inbound packets, so I (guy@alum.mit.edu) don't know
1639 	 * whether that ever needs to be checked or not.
1640 	 *
1641 	 * Note that NetBSD has a DLT_PPP_SERIAL, which it uses for PPP,
1642 	 * and its tcpdump appears to assume that the frame always
1643 	 * begins with an address field and a control field, and that
1644 	 * the address field might be 0x0f or 0x8f, for Cisco
1645 	 * point-to-point with HDLC framing as per section 4.3.1 of RFC
1646 	 * 1547, as well as 0xff, for PPP in HDLC-like framing as per
1647 	 * RFC 1662.
1648 	 *
1649 	 * (Is the Cisco framing in question what DLT_C_HDLC, in
1650 	 * BSD/OS, is?)
1651 	 */
1652 	if (ndo->ndo_eflag)
1653 		ND_PRINT("%c %4d %02x ", GET_U_1(p) ? 'O' : 'I',
1654 			 length, GET_U_1(p + 1));
1655 #endif
1656 
1657 	ppp_print(ndo, p, length);
1658 }
1659 
1660 /*
1661  * PPP I/F printer to use if we know that RFC 1662-style PPP in HDLC-like
1662  * framing, or Cisco PPP with HDLC framing as per section 4.3.1 of RFC 1547,
1663  * is being used (i.e., we don't check for PPP_ADDRESS and PPP_CONTROL,
1664  * discard them *if* those are the first two octets, and parse the remaining
1665  * packet as a PPP packet, as "ppp_print()" does).
1666  *
1667  * This handles, for example, DLT_PPP_SERIAL in NetBSD.
1668  */
1669 void
1670 ppp_hdlc_if_print(netdissect_options *ndo,
1671                   const struct pcap_pkthdr *h, const u_char *p)
1672 {
1673 	u_int length = h->len;
1674 	u_int caplen = h->caplen;
1675 	u_int proto;
1676 	u_int hdrlen = 0;
1677 
1678 	ndo->ndo_protocol = "ppp_hdlc";
1679 	if (caplen < 2) {
1680 		nd_print_trunc(ndo);
1681 		ndo->ndo_ll_hdr_len += caplen;
1682 		return;
1683 	}
1684 
1685 	switch (GET_U_1(p)) {
1686 
1687 	case PPP_ADDRESS:
1688 		if (caplen < 4) {
1689 			nd_print_trunc(ndo);
1690 			ndo->ndo_ll_hdr_len += caplen;
1691 			return;
1692 		}
1693 
1694 		if (ndo->ndo_eflag)
1695 			ND_PRINT("%02x %02x %u ", GET_U_1(p),
1696 				 GET_U_1(p + 1), length);
1697 		p += 2;
1698 		length -= 2;
1699 		hdrlen += 2;
1700 
1701 		proto = GET_BE_U_2(p);
1702 		p += 2;
1703 		length -= 2;
1704 		hdrlen += 2;
1705 		ND_PRINT("%s: ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto));
1706 
1707 		handle_ppp(ndo, proto, p, length);
1708 		break;
1709 
1710 	case CHDLC_UNICAST:
1711 	case CHDLC_BCAST:
1712 		chdlc_if_print(ndo, h, p);
1713 		return;
1714 
1715 	default:
1716 		if (caplen < 4) {
1717 			nd_print_trunc(ndo);
1718 			ndo->ndo_ll_hdr_len += caplen;
1719 			return;
1720 		}
1721 
1722 		if (ndo->ndo_eflag)
1723 			ND_PRINT("%02x %02x %u ", GET_U_1(p),
1724 				 GET_U_1(p + 1), length);
1725 		p += 2;
1726 		hdrlen += 2;
1727 
1728 		/*
1729 		 * XXX - NetBSD's "ppp_netbsd_serial_if_print()" treats
1730 		 * the next two octets as an Ethernet type; does that
1731 		 * ever happen?
1732 		 */
1733 		ND_PRINT("unknown addr %02x; ctrl %02x", GET_U_1(p),
1734 			 GET_U_1(p + 1));
1735 		break;
1736 	}
1737 
1738 	ndo->ndo_ll_hdr_len += hdrlen;
1739 }
1740 
1741 #define PPP_BSDI_HDRLEN 24
1742 
1743 /* BSD/OS specific PPP printer */
1744 void
1745 ppp_bsdos_if_print(netdissect_options *ndo,
1746                    const struct pcap_pkthdr *h _U_, const u_char *p _U_)
1747 {
1748 	u_int hdrlength;
1749 #ifdef __bsdi__
1750 	u_int length = h->len;
1751 	u_int caplen = h->caplen;
1752 	uint16_t ptype;
1753 	uint8_t llhl;
1754 	const u_char *q;
1755 	u_int i;
1756 
1757 	ndo->ndo_protocol = "ppp_bsdos";
1758 	if (caplen < PPP_BSDI_HDRLEN) {
1759 		nd_print_trunc(ndo);
1760 		ndo->ndo_ll_hdr_len += caplen;
1761 		return;
1762 	}
1763 
1764 	hdrlength = 0;
1765 
1766 #if 0
1767 	if (GET_U_1(p) == PPP_ADDRESS &&
1768 	    GET_U_1(p + 1) == PPP_CONTROL) {
1769 		if (ndo->ndo_eflag)
1770 			ND_PRINT("%02x %02x ", GET_U_1(p),
1771 				 GET_U_1(p + 1));
1772 		p += 2;
1773 		hdrlength = 2;
1774 	}
1775 
1776 	if (ndo->ndo_eflag)
1777 		ND_PRINT("%u ", length);
1778 	/* Retrieve the protocol type */
1779 	if (GET_U_1(p) & 01) {
1780 		/* Compressed protocol field */
1781 		ptype = GET_U_1(p);
1782 		if (ndo->ndo_eflag)
1783 			ND_PRINT("%02x ", ptype);
1784 		p++;
1785 		hdrlength += 1;
1786 	} else {
1787 		/* Un-compressed protocol field */
1788 		ptype = GET_BE_U_2(p);
1789 		if (ndo->ndo_eflag)
1790 			ND_PRINT("%04x ", ptype);
1791 		p += 2;
1792 		hdrlength += 2;
1793 	}
1794 #else
1795 	ptype = 0;	/*XXX*/
1796 	if (ndo->ndo_eflag)
1797 		ND_PRINT("%c ", GET_U_1(p + SLC_DIR) ? 'O' : 'I');
1798 	llhl = GET_U_1(p + SLC_LLHL);
1799 	if (llhl) {
1800 		/* link level header */
1801 		struct ppp_header *ph;
1802 
1803 		q = p + SLC_BPFHDRLEN;
1804 		ph = (struct ppp_header *)q;
1805 		if (ph->phdr_addr == PPP_ADDRESS
1806 		 && ph->phdr_ctl == PPP_CONTROL) {
1807 			if (ndo->ndo_eflag)
1808 				ND_PRINT("%02x %02x ", GET_U_1(q),
1809 					 GET_U_1(q + 1));
1810 			ptype = GET_BE_U_2(&ph->phdr_type);
1811 			if (ndo->ndo_eflag && (ptype == PPP_VJC || ptype == PPP_VJNC)) {
1812 				ND_PRINT("%s ", tok2str(ppptype2str,
1813 						"proto-#%u", ptype));
1814 			}
1815 		} else {
1816 			if (ndo->ndo_eflag) {
1817 				ND_PRINT("LLH=[");
1818 				for (i = 0; i < llhl; i++)
1819 					ND_PRINT("%02x", GET_U_1(q + i));
1820 				ND_PRINT("] ");
1821 			}
1822 		}
1823 	}
1824 	if (ndo->ndo_eflag)
1825 		ND_PRINT("%u ", length);
1826 	if (GET_U_1(p + SLC_CHL)) {
1827 		q = p + SLC_BPFHDRLEN + llhl;
1828 
1829 		switch (ptype) {
1830 		case PPP_VJC:
1831 			ptype = vjc_print(ndo, q, ptype);
1832 			hdrlength = PPP_BSDI_HDRLEN;
1833 			p += hdrlength;
1834 			switch (ptype) {
1835 			case PPP_IP:
1836 				ip_print(ndo, p, length);
1837 				break;
1838 			case PPP_IPV6:
1839 				ip6_print(ndo, p, length);
1840 				break;
1841 			case PPP_MPLS_UCAST:
1842 			case PPP_MPLS_MCAST:
1843 				mpls_print(ndo, p, length);
1844 				break;
1845 			}
1846 			goto printx;
1847 		case PPP_VJNC:
1848 			ptype = vjc_print(ndo, q, ptype);
1849 			hdrlength = PPP_BSDI_HDRLEN;
1850 			p += hdrlength;
1851 			switch (ptype) {
1852 			case PPP_IP:
1853 				ip_print(ndo, p, length);
1854 				break;
1855 			case PPP_IPV6:
1856 				ip6_print(ndo, p, length);
1857 				break;
1858 			case PPP_MPLS_UCAST:
1859 			case PPP_MPLS_MCAST:
1860 				mpls_print(ndo, p, length);
1861 				break;
1862 			}
1863 			goto printx;
1864 		default:
1865 			if (ndo->ndo_eflag) {
1866 				ND_PRINT("CH=[");
1867 				for (i = 0; i < llhl; i++)
1868 					ND_PRINT("%02x",
1869 					    GET_U_1(q + i));
1870 				ND_PRINT("] ");
1871 			}
1872 			break;
1873 		}
1874 	}
1875 
1876 	hdrlength = PPP_BSDI_HDRLEN;
1877 #endif
1878 
1879 	length -= hdrlength;
1880 	p += hdrlength;
1881 
1882 	switch (ptype) {
1883 	case PPP_IP:
1884 		ip_print(p, length);
1885 		break;
1886 	case PPP_IPV6:
1887 		ip6_print(ndo, p, length);
1888 		break;
1889 	case PPP_MPLS_UCAST:
1890 	case PPP_MPLS_MCAST:
1891 		mpls_print(ndo, p, length);
1892 		break;
1893 	default:
1894 		ND_PRINT("%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", ptype));
1895 	}
1896 
1897 printx:
1898 #else /* __bsdi */
1899 	hdrlength = 0;
1900 #endif /* __bsdi__ */
1901 	ndo->ndo_ll_hdr_len += hdrlength;
1902 }
1903