xref: /dragonfly/contrib/tcpdump/print-ppp.c (revision 59c07fbdf8168fa08c76c515186d561b5a92690c)
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
handle_ctrl_proto(netdissect_options * ndo,u_int proto,const u_char * pptr,u_int length)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
print_lcp_config_options(netdissect_options * ndo,const u_char * p,u_int length)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
handle_mlppp(netdissect_options * ndo,const u_char * p,u_int length)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
handle_chap(netdissect_options * ndo,const u_char * p,u_int length)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
handle_pap(netdissect_options * ndo,const u_char * p,u_int length)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
handle_bap(netdissect_options * ndo _U_,const u_char * p _U_,u_int length _U_)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
print_ipcp_config_options(netdissect_options * ndo,const u_char * p,u_int length)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
print_ip6cp_config_options(netdissect_options * ndo,const u_char * p,u_int length)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
print_ccp_config_options(netdissect_options * ndo,const u_char * p,u_int length)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
print_bacp_config_options(netdissect_options * ndo,const u_char * p,u_int length)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
ppp_hdlc(netdissect_options * ndo,const u_char * p,u_int length)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 *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            */
1399           se = ndo->ndo_snapend;
1400           ndo->ndo_snapend = t;
1401           length = ND_BYTES_AVAILABLE_AFTER(b);
1402 
1403         /* now lets guess about the payload codepoint format */
1404         if (length < 1)
1405                 goto trunc;
1406         proto = GET_U_1(b); /* start with a one-octet codepoint guess */
1407 
1408         switch (proto) {
1409         case PPP_IP:
1410                     ip_print(ndo, b + 1, length - 1);
1411                     goto cleanup;
1412         case PPP_IPV6:
1413                     ip6_print(ndo, b + 1, length - 1);
1414                     goto cleanup;
1415         default: /* no luck - try next guess */
1416                     break;
1417         }
1418 
1419         if (length < 2)
1420                 goto trunc;
1421         proto = GET_BE_U_2(b); /* next guess - load two octets */
1422 
1423         switch (proto) {
1424         case (PPP_ADDRESS << 8 | PPP_CONTROL): /* looks like a PPP frame */
1425             if (length < 4)
1426                 goto trunc;
1427             proto = GET_BE_U_2(b + 2); /* load the PPP proto-id */
1428             handle_ppp(ndo, proto, b + 4, length - 4);
1429             break;
1430         default: /* last guess - proto must be a PPP proto-id */
1431             handle_ppp(ndo, proto, b + 2, length - 2);
1432             break;
1433         }
1434 
1435 cleanup:
1436           ndo->ndo_snapend = se;
1437         return;
1438 
1439 trunc:
1440           ndo->ndo_snapend = se;
1441           nd_print_trunc(ndo);
1442 }
1443 
1444 
1445 /* PPP */
1446 static void
handle_ppp(netdissect_options * ndo,u_int proto,const u_char * p,u_int length)1447 handle_ppp(netdissect_options *ndo,
1448            u_int proto, const u_char *p, u_int length)
1449 {
1450           if ((proto & 0xff00) == 0x7e00) { /* is this an escape code ? */
1451                     ppp_hdlc(ndo, p - 1, length);
1452                     return;
1453           }
1454 
1455           switch (proto) {
1456           case PPP_LCP: /* fall through */
1457           case PPP_IPCP:
1458           case PPP_OSICP:
1459           case PPP_MPLSCP:
1460           case PPP_IPV6CP:
1461           case PPP_CCP:
1462           case PPP_BACP:
1463                     handle_ctrl_proto(ndo, proto, p, length);
1464                     break;
1465           case PPP_ML:
1466                     handle_mlppp(ndo, p, length);
1467                     break;
1468           case PPP_CHAP:
1469                     handle_chap(ndo, p, length);
1470                     break;
1471           case PPP_PAP:
1472                     handle_pap(ndo, p, length);
1473                     break;
1474           case PPP_BAP:                 /* XXX: not yet completed */
1475                     handle_bap(ndo, p, length);
1476                     break;
1477           case ETHERTYPE_IP:  /*XXX*/
1478         case PPP_VJNC:
1479           case PPP_IP:
1480                     ip_print(ndo, p, length);
1481                     break;
1482           case ETHERTYPE_IPV6:          /*XXX*/
1483           case PPP_IPV6:
1484                     ip6_print(ndo, p, length);
1485                     break;
1486           case ETHERTYPE_IPX: /*XXX*/
1487           case PPP_IPX:
1488                     ipx_print(ndo, p, length);
1489                     break;
1490           case PPP_OSI:
1491                     isoclns_print(ndo, p, length);
1492                     break;
1493           case PPP_MPLS_UCAST:
1494           case PPP_MPLS_MCAST:
1495                     mpls_print(ndo, p, length);
1496                     break;
1497           case PPP_COMP:
1498                     ND_PRINT("compressed PPP data");
1499                     break;
1500           default:
1501                     ND_PRINT("%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto));
1502                     print_unknown_data(ndo, p, "\n\t", length);
1503                     break;
1504           }
1505 }
1506 
1507 /* Standard PPP printer */
1508 u_int
ppp_print(netdissect_options * ndo,const u_char * p,u_int length)1509 ppp_print(netdissect_options *ndo,
1510           const u_char *p, u_int length)
1511 {
1512           u_int proto,ppp_header;
1513         u_int olen = length; /* _o_riginal length */
1514           u_int hdr_len = 0;
1515 
1516           ndo->ndo_protocol = "ppp";
1517           /*
1518            * Here, we assume that p points to the Address and Control
1519            * field (if they present).
1520            */
1521           if (length < 2)
1522                     goto trunc;
1523         ppp_header = GET_BE_U_2(p);
1524 
1525         switch(ppp_header) {
1526         case (PPP_PPPD_IN  << 8 | PPP_CONTROL):
1527             if (ndo->ndo_eflag) ND_PRINT("In  ");
1528             p += 2;
1529             length -= 2;
1530             hdr_len += 2;
1531             break;
1532         case (PPP_PPPD_OUT << 8 | PPP_CONTROL):
1533             if (ndo->ndo_eflag) ND_PRINT("Out ");
1534             p += 2;
1535             length -= 2;
1536             hdr_len += 2;
1537             break;
1538         case (PPP_ADDRESS << 8 | PPP_CONTROL):
1539             p += 2;                     /* ACFC not used */
1540             length -= 2;
1541             hdr_len += 2;
1542             break;
1543 
1544         default:
1545             break;
1546         }
1547 
1548           if (length < 2)
1549                     goto trunc;
1550           if (GET_U_1(p) % 2) {
1551                     proto = GET_U_1(p); /* PFC is used */
1552                     p++;
1553                     length--;
1554                     hdr_len++;
1555           } else {
1556                     proto = GET_BE_U_2(p);
1557                     p += 2;
1558                     length -= 2;
1559                     hdr_len += 2;
1560           }
1561 
1562           if (ndo->ndo_eflag)
1563                     ND_PRINT("%s (0x%04x), length %u: ",
1564                               tok2str(ppptype2str, "unknown", proto),
1565                               proto,
1566                               olen);
1567 
1568           handle_ppp(ndo, proto, p, length);
1569           return (hdr_len);
1570 trunc:
1571           nd_print_trunc(ndo);
1572           return (0);
1573 }
1574 
1575 
1576 /* PPP I/F printer */
1577 void
ppp_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,const u_char * p)1578 ppp_if_print(netdissect_options *ndo,
1579              const struct pcap_pkthdr *h, const u_char *p)
1580 {
1581           u_int length = h->len;
1582           u_int caplen = h->caplen;
1583 
1584           ndo->ndo_protocol = "ppp";
1585           if (caplen < PPP_HDRLEN) {
1586                     nd_print_trunc(ndo);
1587                     ndo->ndo_ll_hdr_len += caplen;
1588                     return;
1589           }
1590           ndo->ndo_ll_hdr_len += PPP_HDRLEN;
1591 
1592 #if 0
1593           /*
1594            * XXX: seems to assume that there are 2 octets prepended to an
1595            * actual PPP frame. The 1st octet looks like Input/Output flag
1596            * while 2nd octet is unknown, at least to me
1597            * (mshindo@mshindo.net).
1598            *
1599            * That was what the original tcpdump code did.
1600            *
1601            * FreeBSD's "if_ppp.c" *does* set the first octet to 1 for outbound
1602            * packets and 0 for inbound packets - but only if the
1603            * protocol field has the 0x8000 bit set (i.e., it's a network
1604            * control protocol); it does so before running the packet through
1605            * "bpf_filter" to see if it should be discarded, and to see
1606            * if we should update the time we sent the most recent packet...
1607            *
1608            * ...but it puts the original address field back after doing
1609            * so.
1610            *
1611            * NetBSD's "if_ppp.c" doesn't set the first octet in that fashion.
1612            *
1613            * I don't know if any PPP implementation handed up to a BPF
1614            * device packets with the first octet being 1 for outbound and
1615            * 0 for inbound packets, so I (guy@alum.mit.edu) don't know
1616            * whether that ever needs to be checked or not.
1617            *
1618            * Note that NetBSD has a DLT_PPP_SERIAL, which it uses for PPP,
1619            * and its tcpdump appears to assume that the frame always
1620            * begins with an address field and a control field, and that
1621            * the address field might be 0x0f or 0x8f, for Cisco
1622            * point-to-point with HDLC framing as per section 4.3.1 of RFC
1623            * 1547, as well as 0xff, for PPP in HDLC-like framing as per
1624            * RFC 1662.
1625            *
1626            * (Is the Cisco framing in question what DLT_C_HDLC, in
1627            * BSD/OS, is?)
1628            */
1629           if (ndo->ndo_eflag)
1630                     ND_PRINT("%c %4d %02x ", GET_U_1(p) ? 'O' : 'I',
1631                                length, GET_U_1(p + 1));
1632 #endif
1633 
1634           ppp_print(ndo, p, length);
1635 }
1636 
1637 /*
1638  * PPP I/F printer to use if we know that RFC 1662-style PPP in HDLC-like
1639  * framing, or Cisco PPP with HDLC framing as per section 4.3.1 of RFC 1547,
1640  * is being used (i.e., we don't check for PPP_ADDRESS and PPP_CONTROL,
1641  * discard them *if* those are the first two octets, and parse the remaining
1642  * packet as a PPP packet, as "ppp_print()" does).
1643  *
1644  * This handles, for example, DLT_PPP_SERIAL in NetBSD.
1645  */
1646 void
ppp_hdlc_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,const u_char * p)1647 ppp_hdlc_if_print(netdissect_options *ndo,
1648                   const struct pcap_pkthdr *h, const u_char *p)
1649 {
1650           u_int length = h->len;
1651           u_int caplen = h->caplen;
1652           u_int proto;
1653           u_int hdrlen = 0;
1654 
1655           ndo->ndo_protocol = "ppp_hdlc";
1656           if (caplen < 2) {
1657                     nd_print_trunc(ndo);
1658                     ndo->ndo_ll_hdr_len += caplen;
1659                     return;
1660           }
1661 
1662           switch (GET_U_1(p)) {
1663 
1664           case PPP_ADDRESS:
1665                     if (caplen < 4) {
1666                               nd_print_trunc(ndo);
1667                               ndo->ndo_ll_hdr_len += caplen;
1668                               return;
1669                     }
1670 
1671                     if (ndo->ndo_eflag)
1672                               ND_PRINT("%02x %02x %u ", GET_U_1(p),
1673                                          GET_U_1(p + 1), length);
1674                     p += 2;
1675                     length -= 2;
1676                     hdrlen += 2;
1677 
1678                     proto = GET_BE_U_2(p);
1679                     p += 2;
1680                     length -= 2;
1681                     hdrlen += 2;
1682                     ND_PRINT("%s: ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto));
1683 
1684                     handle_ppp(ndo, proto, p, length);
1685                     break;
1686 
1687           case CHDLC_UNICAST:
1688           case CHDLC_BCAST:
1689                     chdlc_if_print(ndo, h, p);
1690                     return;
1691 
1692           default:
1693                     if (caplen < 4) {
1694                               nd_print_trunc(ndo);
1695                               ndo->ndo_ll_hdr_len += caplen;
1696                               return;
1697                     }
1698 
1699                     if (ndo->ndo_eflag)
1700                               ND_PRINT("%02x %02x %u ", GET_U_1(p),
1701                                          GET_U_1(p + 1), length);
1702                     p += 2;
1703                     hdrlen += 2;
1704 
1705                     /*
1706                      * XXX - NetBSD's "ppp_netbsd_serial_if_print()" treats
1707                      * the next two octets as an Ethernet type; does that
1708                      * ever happen?
1709                      */
1710                     ND_PRINT("unknown addr %02x; ctrl %02x", GET_U_1(p),
1711                                GET_U_1(p + 1));
1712                     break;
1713           }
1714 
1715           ndo->ndo_ll_hdr_len += hdrlen;
1716 }
1717 
1718 #define PPP_BSDI_HDRLEN 24
1719 
1720 /* BSD/OS specific PPP printer */
1721 void
ppp_bsdos_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h _U_,const u_char * p _U_)1722 ppp_bsdos_if_print(netdissect_options *ndo,
1723                    const struct pcap_pkthdr *h _U_, const u_char *p _U_)
1724 {
1725           u_int hdrlength;
1726 #ifdef __bsdi__
1727           u_int length = h->len;
1728           u_int caplen = h->caplen;
1729           uint16_t ptype;
1730           uint8_t llhl;
1731           const u_char *q;
1732           u_int i;
1733 
1734           ndo->ndo_protocol = "ppp_bsdos";
1735           if (caplen < PPP_BSDI_HDRLEN) {
1736                     nd_print_trunc(ndo);
1737                     ndo->ndo_ll_hdr_len += caplen;
1738                     return;
1739           }
1740 
1741           hdrlength = 0;
1742 
1743 #if 0
1744           if (GET_U_1(p) == PPP_ADDRESS &&
1745               GET_U_1(p + 1) == PPP_CONTROL) {
1746                     if (ndo->ndo_eflag)
1747                               ND_PRINT("%02x %02x ", GET_U_1(p),
1748                                          GET_U_1(p + 1));
1749                     p += 2;
1750                     hdrlength = 2;
1751           }
1752 
1753           if (ndo->ndo_eflag)
1754                     ND_PRINT("%u ", length);
1755           /* Retrieve the protocol type */
1756           if (GET_U_1(p) & 01) {
1757                     /* Compressed protocol field */
1758                     ptype = GET_U_1(p);
1759                     if (ndo->ndo_eflag)
1760                               ND_PRINT("%02x ", ptype);
1761                     p++;
1762                     hdrlength += 1;
1763           } else {
1764                     /* Un-compressed protocol field */
1765                     ptype = GET_BE_U_2(p);
1766                     if (ndo->ndo_eflag)
1767                               ND_PRINT("%04x ", ptype);
1768                     p += 2;
1769                     hdrlength += 2;
1770           }
1771 #else
1772           ptype = 0;          /*XXX*/
1773           if (ndo->ndo_eflag)
1774                     ND_PRINT("%c ", GET_U_1(p + SLC_DIR) ? 'O' : 'I');
1775           llhl = GET_U_1(p + SLC_LLHL);
1776           if (llhl) {
1777                     /* link level header */
1778                     struct ppp_header *ph;
1779 
1780                     q = p + SLC_BPFHDRLEN;
1781                     ph = (struct ppp_header *)q;
1782                     if (ph->phdr_addr == PPP_ADDRESS
1783                      && ph->phdr_ctl == PPP_CONTROL) {
1784                               if (ndo->ndo_eflag)
1785                                         ND_PRINT("%02x %02x ", GET_U_1(q),
1786                                                    GET_U_1(q + 1));
1787                               ptype = GET_BE_U_2(&ph->phdr_type);
1788                               if (ndo->ndo_eflag && (ptype == PPP_VJC || ptype == PPP_VJNC)) {
1789                                         ND_PRINT("%s ", tok2str(ppptype2str,
1790                                                             "proto-#%u", ptype));
1791                               }
1792                     } else {
1793                               if (ndo->ndo_eflag) {
1794                                         ND_PRINT("LLH=[");
1795                                         for (i = 0; i < llhl; i++)
1796                                                   ND_PRINT("%02x", GET_U_1(q + i));
1797                                         ND_PRINT("] ");
1798                               }
1799                     }
1800           }
1801           if (ndo->ndo_eflag)
1802                     ND_PRINT("%u ", length);
1803           if (GET_U_1(p + SLC_CHL)) {
1804                     q = p + SLC_BPFHDRLEN + llhl;
1805 
1806                     switch (ptype) {
1807                     case PPP_VJC:
1808                               ptype = vjc_print(ndo, q, ptype);
1809                               hdrlength = PPP_BSDI_HDRLEN;
1810                               p += hdrlength;
1811                               switch (ptype) {
1812                               case PPP_IP:
1813                                         ip_print(ndo, p, length);
1814                                         break;
1815                               case PPP_IPV6:
1816                                         ip6_print(ndo, p, length);
1817                                         break;
1818                               case PPP_MPLS_UCAST:
1819                               case PPP_MPLS_MCAST:
1820                                         mpls_print(ndo, p, length);
1821                                         break;
1822                               }
1823                               goto printx;
1824                     case PPP_VJNC:
1825                               ptype = vjc_print(ndo, q, ptype);
1826                               hdrlength = PPP_BSDI_HDRLEN;
1827                               p += hdrlength;
1828                               switch (ptype) {
1829                               case PPP_IP:
1830                                         ip_print(ndo, p, length);
1831                                         break;
1832                               case PPP_IPV6:
1833                                         ip6_print(ndo, p, length);
1834                                         break;
1835                               case PPP_MPLS_UCAST:
1836                               case PPP_MPLS_MCAST:
1837                                         mpls_print(ndo, p, length);
1838                                         break;
1839                               }
1840                               goto printx;
1841                     default:
1842                               if (ndo->ndo_eflag) {
1843                                         ND_PRINT("CH=[");
1844                                         for (i = 0; i < llhl; i++)
1845                                                   ND_PRINT("%02x",
1846                                                       GET_U_1(q + i));
1847                                         ND_PRINT("] ");
1848                               }
1849                               break;
1850                     }
1851           }
1852 
1853           hdrlength = PPP_BSDI_HDRLEN;
1854 #endif
1855 
1856           length -= hdrlength;
1857           p += hdrlength;
1858 
1859           switch (ptype) {
1860           case PPP_IP:
1861                     ip_print(p, length);
1862                     break;
1863           case PPP_IPV6:
1864                     ip6_print(ndo, p, length);
1865                     break;
1866           case PPP_MPLS_UCAST:
1867           case PPP_MPLS_MCAST:
1868                     mpls_print(ndo, p, length);
1869                     break;
1870           default:
1871                     ND_PRINT("%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", ptype));
1872           }
1873 
1874 printx:
1875 #else /* __bsdi */
1876           hdrlength = 0;
1877 #endif /* __bsdi__ */
1878           ndo->ndo_ll_hdr_len += hdrlength;
1879 }
1880