The Tcpdump Group git mirrors - tcpdump/blob - print-fr.c

   1 /*
   2  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 #ifndef lint
  23 static const char rcsid[] _U_ =
  24         "@(#)$Header: /tcpdump/master/tcpdump/print-fr.c,v 1.36 2005-05-27 14:53:48 hannes Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <tcpdump-stdinc.h>
  32
  33 #include <stdio.h>
  34 #include <string.h>
  35 #include <pcap.h>
  36
  37 #include "addrtoname.h"
  38 #include "interface.h"
  39 #include "ethertype.h"
  40 #include "nlpid.h"
  41 #include "extract.h"
  42 #include "oui.h"
  43
  44 static void frf15_print(const u_char *, u_int);
  45
  46 /*
  47  * the frame relay header has a variable length
  48  *
  49  * the EA bit determines if there is another byte
  50  * in the header
  51  *
  52  * minimum header length is 2 bytes
  53  * maximum header length is 4 bytes
  54  *
  55  *      7    6    5    4    3    2    1    0
  56  *    +----+----+----+----+----+----+----+----+
  57  *    |        DLCI (6 bits)        | CR | EA |
  58  *    +----+----+----+----+----+----+----+----+
  59  *    |   DLCI (4 bits)   |FECN|BECN| DE | EA |
  60  *    +----+----+----+----+----+----+----+----+
  61  *    |           DLCI (7 bits)          | EA |
  62  *    +----+----+----+----+----+----+----+----+
  63  *    |        DLCI (6 bits)        |SDLC| EA |
  64  *    +----+----+----+----+----+----+----+----+
  65  */
  66
  67 #define FR_EA_BIT       0x01
  68
  69 #define FR_CR_BIT       0x02000000
  70 #define FR_DE_BIT       0x00020000
  71 #define FR_BECN_BIT     0x00040000
  72 #define FR_FECN_BIT     0x00080000
  73 #define FR_SDLC_BIT     0x00000002
  74
  75
  76 struct tok fr_header_flag_values[] = {
  77     { FR_CR_BIT, "C!" },
  78     { FR_DE_BIT, "DE" },
  79     { FR_BECN_BIT, "BECN" },
  80     { FR_FECN_BIT, "FECN" },
  81     { FR_SDLC_BIT, "sdlcore" },
  82     { 0, NULL }
  83 };
  84
  85
  86 /* Finds out Q.922 address length, DLCI and flags. Returns 0 on success
  87  * save the flags dep. on address length
  88  */
  89 static int parse_q922_addr(const u_char *p, u_int *dlci, u_int *sdlcore,
  90                            u_int *addr_len, u_int8_t *flags)
  91 {
  92         if ((p[0] & FR_EA_BIT))
  93                 return -1;
  94
  95         *addr_len = 2;
  96         *dlci = ((p[0] & 0xFC) << 2) | ((p[1] & 0xF0) >> 4);
  97
  98         flags[0] = p[0] & 0x02; /* populate the first flag fields */
  99         flags[1] = p[1] & 0x0c;
 100
 101         if (p[1] & FR_EA_BIT)
 102                 return 0;       /* 2-byte Q.922 address */
 103
 104         p += 2;
 105         (*addr_len)++;          /* 3- or 4-byte Q.922 address */
 106         if ((p[0] & FR_EA_BIT) == 0) {
 107                 *dlci = (*dlci << 7) | (p[0] >> 1);
 108                 (*addr_len)++;  /* 4-byte Q.922 address */
 109                 p++;
 110         }
 111
 112         if ((p[0] & FR_EA_BIT) == 0)
 113                 return -1; /* more than 4 bytes of Q.922 address? */
 114
 115         flags[3] = p[0] & 0x02;
 116
 117         if (p[0] & 0x02)
 118                 *sdlcore =  p[0] >> 2;
 119         else
 120                 *dlci = (*dlci << 6) | (p[0] >> 2);
 121
 122         return 0;
 123 }
 124
 125 /* Frame Relay packet structure, with flags and CRC removed
 126
 127                   +---------------------------+
 128                   |       Q.922 Address*      |
 129                   +--                       --+
 130                   |                           |
 131                   +---------------------------+
 132                   | Control (UI = 0x03)       |
 133                   +---------------------------+
 134                   | Optional Pad      (0x00)  |
 135                   +---------------------------+
 136                   | NLPID                     |
 137                   +---------------------------+
 138                   |             .             |
 139                   |             .             |
 140                   |             .             |
 141                   |           Data            |
 142                   |             .             |
 143                   |             .             |
 144                   +---------------------------+
 145
 146            * Q.922 addresses, as presently defined, are two octets and
 147              contain a 10-bit DLCI.  In some networks Q.922 addresses
 148              may optionally be increased to three or four octets.
 149 */
 150
 151 static u_int
 152 fr_hdrlen(const u_char *p, u_int addr_len)
 153 {
 154         if (!p[addr_len + 1] /* pad exist */)
 155                 return addr_len + 1 /* UI */ + 1 /* pad */ + 1 /* NLPID */;
 156         else
 157                 return addr_len + 1 /* UI */ + 1 /* NLPID */;
 158 }
 159
 160 static void
 161 fr_hdr_print(int length, u_int addr_len, u_int dlci, u_int8_t *flags, u_int16_t nlpid)
 162 {
 163     if (qflag) {
 164         (void)printf("Q.922, DLCI %u, length %u: ",
 165                      dlci,
 166                      length);
 167     } else {
 168         if (nlpid <= 0xff) /* if its smaller than 256 then its a NLPID */
 169             (void)printf("Q.922, hdr-len %u, DLCI %u, Flags [%s], NLPID %s (0x%02x), length %u: ",
 170                          addr_len,
 171                          dlci,
 172                          bittok2str(fr_header_flag_values, "none", EXTRACT_32BITS(flags)),
 173                          tok2str(nlpid_values,"unknown", nlpid),
 174                          nlpid,
 175                          length);
 176         else /* must be an ethertype */
 177             (void)printf("Q.922, hdr-len %u, DLCI %u, Flags [%s], cisco-ethertype %s (0x%04x), length %u: ",
 178                          addr_len,
 179                          dlci,
 180                          bittok2str(fr_header_flag_values, "none", EXTRACT_32BITS(flags)),
 181                          tok2str(ethertype_values, "unknown", nlpid),
 182                          nlpid,
 183                          length);
 184     }
 185 }
 186
 187 u_int
 188 fr_if_print(const struct pcap_pkthdr *h, register const u_char *p)
 189 {
 190         register u_int length = h->len;
 191         register u_int caplen = h->caplen;
 192
 193         TCHECK2(*p, 4); /* minimum frame header length */
 194
 195         if ((length = fr_print(p, length)) == 0)
 196             return (0);
 197         else
 198             return length;
 199  trunc:
 200         printf("[|fr]");
 201         return caplen;
 202 }
 203
 204 u_int
 205 fr_print(register const u_char *p, u_int length)
 206 {
 207         u_int16_t extracted_ethertype;
 208         u_int dlci;
 209         u_int sdlcore;
 210         u_int addr_len;
 211         u_int16_t nlpid;
 212         u_int hdr_len;
 213         u_int8_t flags[4];
 214
 215         if (parse_q922_addr(p, &dlci, &sdlcore, &addr_len, flags)) {
 216                 printf("Q.922, invalid address");
 217                 return 0;
 218         }
 219
 220         TCHECK2(*p,addr_len+1+1);
 221         hdr_len = fr_hdrlen(p, addr_len);
 222         TCHECK2(*p,hdr_len);
 223
 224         if (p[addr_len] != 0x03 && dlci != 0) {
 225
 226                 /* lets figure out if we have cisco style encapsulation: */
 227                 extracted_ethertype = EXTRACT_16BITS(p+addr_len);
 228
 229                 if (eflag)
 230                     fr_hdr_print(length, addr_len, dlci, flags, extracted_ethertype);
 231
 232                 if (ether_encap_print(extracted_ethertype,
 233                                       p+addr_len+ETHERTYPE_LEN,
 234                                       length-addr_len-ETHERTYPE_LEN,
 235                                       length-addr_len-ETHERTYPE_LEN,
 236                                       &extracted_ethertype) == 0)
 237                     /* ether_type not known, probably it wasn't one */
 238                     printf("UI %02x! ", p[addr_len]);
 239                 else
 240                     return hdr_len;
 241         }
 242
 243         if (!p[addr_len + 1]) { /* pad byte should be used with 3-byte Q.922 */
 244                 if (addr_len != 3)
 245                         printf("Pad! ");
 246         } else if (addr_len == 3)
 247                 printf("No pad! ");
 248
 249         nlpid = p[hdr_len - 1];
 250
 251         if (eflag)
 252                 fr_hdr_print(length, addr_len, dlci, flags, nlpid);
 253
 254         p += hdr_len;
 255         length -= hdr_len;
 256
 257         switch (nlpid) {
 258         case NLPID_IP:
 259                 ip_print(gndo, p, length);
 260                 break;
 261
 262 #ifdef INET6
 263         case NLPID_IP6:
 264                 ip6_print(p, length);
 265                 break;
 266 #endif
 267         case NLPID_CLNP:
 268         case NLPID_ESIS:
 269         case NLPID_ISIS:
 270                 isoclns_print(p-1, length+1, length+1); /* OSI printers need the NLPID field */
 271                 break;
 272
 273         case NLPID_SNAP:
 274                 if (snap_print(p, length, length, &extracted_ethertype, 0) == 0) {
 275                         /* ether_type not known, print raw packet */
 276                         if (!eflag)
 277                             fr_hdr_print(length + hdr_len, hdr_len,
 278                                          dlci, flags, nlpid);
 279                         if (!xflag && !qflag)
 280                             default_print(p - hdr_len, length + hdr_len);
 281                 }
 282                 break;
 283
 284         case NLPID_Q933:
 285                 q933_print(p, length);
 286                 break;
 287
 288         case NLPID_MFR:
 289                 frf15_print(p, length);
 290                 break;
 291
 292         default:
 293                 if (!eflag)
 294                     fr_hdr_print(length + hdr_len, addr_len,
 295                                      dlci, flags, nlpid);
 296                 if (!xflag)
 297                         default_print(p, length);
 298         }
 299
 300         return hdr_len;
 301
 302  trunc:
 303         printf("[|fr]");
 304         return 0;
 305
 306 }
 307
 308 /* an NLPID of 0xb1 indicates a 2-byte
 309  * FRF.15 header
 310  *
 311  *      7    6    5    4    3    2    1    0
 312  *    +----+----+----+----+----+----+----+----+
 313  *    ~              Q.922 header             ~
 314  *    +----+----+----+----+----+----+----+----+
 315  *    |             NLPID (8 bits)            | NLPID=0xb1
 316  *    +----+----+----+----+----+----+----+----+
 317  *    | B  | E  | C  |seq. (high 4 bits) | R  |
 318  *    +----+----+----+----+----+----+----+----+
 319  *    |        sequence  (low 8 bits)         |
 320  *    +----+----+----+----+----+----+----+----+
 321  */
 322
 323 struct tok frf15_flag_values[] = {
 324     { 0x80, "Begin" },
 325     { 0x40, "End" },
 326     { 0x20, "Control" },
 327     { 0, NULL }
 328 };
 329
 330 #define FR_FRF15_FRAGTYPE 0x01
 331
 332 static void
 333 frf15_print (const u_char *p, u_int length) {
 334
 335     u_int16_t sequence_num, flags;
 336
 337     flags = p[0]&0xe0;
 338     sequence_num = (p[0]&0x1e)<<7 | p[1];
 339
 340     printf("FRF.15, seq 0x%03x, Flags [%s],%s Fragmentation, length %u",
 341            sequence_num,
 342            bittok2str(frf15_flag_values,"none",flags),
 343            flags&FR_FRF15_FRAGTYPE ? "Interface" : "End-to-End",
 344            length);
 345
 346 /* TODO:
 347  * depending on all permutations of the B, E and C bit
 348  * dig as deep as we can - e.g. on the first (B) fragment
 349  * there is enough payload to print the IP header
 350  * on non (B) fragments it depends if the fragmentation
 351  * model is end-to-end or interface based wether we want to print
 352  * another Q.922 header
 353  */
 354
 355 }
 356
 357 /*
 358  * Q.933 decoding portion for framerelay specific.
 359  */
 360
 361 /* Q.933 packet format
 362                       Format of Other Protocols
 363                           using Q.933 NLPID
 364                   +-------------------------------+
 365                   |        Q.922 Address          |
 366                   +---------------+---------------+
 367                   |Control  0x03  | NLPID   0x08  |
 368                   +---------------+---------------+
 369                   |          L2 Protocol ID       |
 370                   | octet 1       |  octet 2      |
 371                   +-------------------------------+
 372                   |          L3 Protocol ID       |
 373                   | octet 2       |  octet 2      |
 374                   +-------------------------------+
 375                   |         Protocol Data         |
 376                   +-------------------------------+
 377                   | FCS                           |
 378                   +-------------------------------+
 379  */
 380
 381 /* L2 (Octet 1)- Call Reference Usually is 0x0 */
 382
 383 /*
 384  * L2 (Octet 2)- Message Types definition 1 byte long.
 385  */
 386 /* Call Establish */
 387 #define MSG_TYPE_ESC_TO_NATIONAL  0x00
 388 #define MSG_TYPE_ALERT            0x01
 389 #define MSG_TYPE_CALL_PROCEEDING  0x02
 390 #define MSG_TYPE_CONNECT          0x07
 391 #define MSG_TYPE_CONNECT_ACK      0x0F
 392 #define MSG_TYPE_PROGRESS         0x03
 393 #define MSG_TYPE_SETUP            0x05
 394 /* Call Clear */
 395 #define MSG_TYPE_DISCONNECT       0x45
 396 #define MSG_TYPE_RELEASE          0x4D
 397 #define MSG_TYPE_RELEASE_COMPLETE 0x5A
 398 #define MSG_TYPE_RESTART          0x46
 399 #define MSG_TYPE_RESTART_ACK      0x4E
 400 /* Status */
 401 #define MSG_TYPE_STATUS           0x7D
 402 #define MSG_TYPE_STATUS_ENQ       0x75
 403
 404 struct tok fr_q933_msg_values[] = {
 405     { MSG_TYPE_ESC_TO_NATIONAL, "ESC to National" },
 406     { MSG_TYPE_ALERT, "Alert" },
 407     { MSG_TYPE_CALL_PROCEEDING, "Call proceeding" },
 408     { MSG_TYPE_CONNECT, "Connect" },
 409     { MSG_TYPE_CONNECT_ACK, "Connect ACK" },
 410     { MSG_TYPE_PROGRESS, "Progress" },
 411     { MSG_TYPE_SETUP, "Setup" },
 412     { MSG_TYPE_DISCONNECT, "Disconnect" },
 413     { MSG_TYPE_RELEASE, "Release" },
 414     { MSG_TYPE_RELEASE_COMPLETE, "Release Complete" },
 415     { MSG_TYPE_RESTART, "Restart" },
 416     { MSG_TYPE_RESTART_ACK, "Restart ACK" },
 417     { MSG_TYPE_STATUS, "Status Reply" },
 418     { MSG_TYPE_STATUS_ENQ, "Status Enquiry" },
 419     { 0, NULL }
 420 };
 421
 422 #define MSG_ANSI_LOCKING_SHIFT  0x95
 423
 424 #define FR_LMI_ANSI_REPORT_TYPE_IE      0x01
 425 #define FR_LMI_ANSI_LINK_VERIFY_IE_91   0x19 /* details? */
 426 #define FR_LMI_ANSI_LINK_VERIFY_IE      0x03
 427 #define FR_LMI_ANSI_PVC_STATUS_IE       0x07
 428
 429 #define FR_LMI_CCITT_REPORT_TYPE_IE     0x51
 430 #define FR_LMI_CCITT_LINK_VERIFY_IE     0x53
 431 #define FR_LMI_CCITT_PVC_STATUS_IE      0x57
 432
 433 struct tok fr_q933_ie_values_codeset5[] = {
 434     { FR_LMI_ANSI_REPORT_TYPE_IE, "ANSI Report Type" },
 435     { FR_LMI_ANSI_LINK_VERIFY_IE_91, "ANSI Link Verify" },
 436     { FR_LMI_ANSI_LINK_VERIFY_IE, "ANSI Link Verify" },
 437     { FR_LMI_ANSI_PVC_STATUS_IE, "ANSI PVC Status" },
 438     { FR_LMI_CCITT_REPORT_TYPE_IE, "CCITT Report Type" },
 439     { FR_LMI_CCITT_LINK_VERIFY_IE, "CCITT Link Verify" },
 440     { FR_LMI_CCITT_PVC_STATUS_IE, "CCITT PVC Status" },
 441     { 0, NULL }
 442 };
 443
 444 #define FR_LMI_REPORT_TYPE_IE_FULL_STATUS 0
 445 #define FR_LMI_REPORT_TYPE_IE_LINK_VERIFY 1
 446 #define FR_LMI_REPORT_TYPE_IE_ASYNC_PVC   2
 447
 448 struct tok fr_lmi_report_type_ie_values[] = {
 449     { FR_LMI_REPORT_TYPE_IE_FULL_STATUS, "Full Status" },
 450     { FR_LMI_REPORT_TYPE_IE_LINK_VERIFY, "Link verify" },
 451     { FR_LMI_REPORT_TYPE_IE_ASYNC_PVC, "Async PVC Status" },
 452     { 0, NULL }
 453 };
 454
 455 /* array of 16 codepages - currently we only support codepage 5 */
 456 static struct tok *fr_q933_ie_codesets[] = {
 457     NULL,
 458     NULL,
 459     NULL,
 460     NULL,
 461     NULL,
 462     fr_q933_ie_values_codeset5,
 463     NULL,
 464     NULL,
 465     NULL,
 466     NULL,
 467     NULL,
 468     NULL,
 469     NULL,
 470     NULL,
 471     NULL,
 472     NULL
 473 };
 474
 475
 476 struct common_ie_header {
 477     u_int8_t ie_id;
 478     u_int8_t ie_len;
 479 };
 480
 481 static int fr_q933_print_ie_codeset5(const struct common_ie_header *ie_p,
 482     const u_char *p);
 483
 484 typedef int (*codeset_pr_func_t)(const struct common_ie_header *ie_p,
 485     const u_char *p);
 486
 487 /* array of 16 codepages - currently we only support codepage 5 */
 488 static codeset_pr_func_t fr_q933_print_ie_codeset[] = {
 489     NULL,
 490     NULL,
 491     NULL,
 492     NULL,
 493     NULL,
 494     fr_q933_print_ie_codeset5,
 495     NULL,
 496     NULL,
 497     NULL,
 498     NULL,
 499     NULL,
 500     NULL,
 501     NULL,
 502     NULL,
 503     NULL,
 504     NULL
 505 };
 506
 507 void
 508 q933_print(const u_char *p, u_int length)
 509 {
 510         const u_char *ptemp = p;
 511         struct common_ie_header *ie_p;
 512         int olen;
 513         int is_ansi = 0;
 514         u_int codeset;
 515
 516         if (length < 9) {       /* shortest: Q.933a LINK VERIFY */
 517                 printf("[|q.933]");
 518                 return;
 519         }
 520
 521         codeset = p[2]&0x0f;   /* extract the codeset */
 522
 523         if (p[2] == MSG_ANSI_LOCKING_SHIFT)
 524                 is_ansi = 1;
 525
 526         printf("%s", eflag ? "" : "Q.933, ");
 527
 528         /* printing out header part */
 529         printf(is_ansi ? "ANSI" : "CCITT");
 530
 531         if (p[0])
 532                 printf(", Call Ref: 0x%02x", p[0]);
 533
 534         if (vflag)
 535             printf(", %s (0x%02x), length %u",
 536                    tok2str(fr_q933_msg_values,"unknown message",p[1]),
 537                    p[1],
 538                    length);
 539         else
 540             printf(", %s",
 541                    tok2str(fr_q933_msg_values,"unknown message 0x%02x",p[1]));
 542
 543         olen = length; /* preserve the original length for non verbose mode */
 544
 545         if (length < (u_int)(2 - is_ansi)) {
 546                 printf("[|q.933]");
 547                 return;
 548         }
 549         length -= 2 - is_ansi;
 550         ptemp += 2 + is_ansi;
 551
 552         /* Loop through the rest of IE */
 553         while (length > sizeof(struct common_ie_header)) {
 554                 ie_p = (struct common_ie_header *)ptemp;
 555                 if (length < sizeof(struct common_ie_header) ||
 556                     length < sizeof(struct common_ie_header) + ie_p->ie_len) {
 557                     if (vflag) /* not bark if there is just a trailer */
 558                         printf("\n[|q.933]");
 559                     else
 560                         printf(", length %u",olen);
 561                     return;
 562                 }
 563
 564                 /* lets do the full IE parsing only in verbose mode
 565                  * however some IEs (DLCI Status, Link Verify)
 566                  * are also intereststing in non-verbose mode */
 567                 if (vflag)
 568                     printf("\n\t%s IE (%u), length %u: ",
 569                            tok2str(fr_q933_ie_codesets[codeset],"unknown",ie_p->ie_id),
 570                            ie_p->ie_id,
 571                            ie_p->ie_len);
 572
 573                 if (!fr_q933_print_ie_codeset[codeset] ||
 574                     (*fr_q933_print_ie_codeset[codeset])(ie_p, ptemp)) {
 575                     if (vflag <= 1)
 576                         print_unknown_data(ptemp+2,"\n\t",ie_p->ie_len);
 577                 }
 578
 579                 /* do we want to see a hexdump of the IE ? */
 580                 if (vflag> 1)
 581                     print_unknown_data(ptemp+2,"\n\t  ",ie_p->ie_len);
 582
 583                 length = length - ie_p->ie_len - 2;
 584                 ptemp = ptemp + ie_p->ie_len + 2;
 585         }
 586         if (!vflag)
 587             printf(", length %u",olen);
 588 }
 589
 590 static int
 591 fr_q933_print_ie_codeset5(const struct common_ie_header *ie_p, const u_char *p)
 592 {
 593         u_int dlci;
 594
 595         switch (ie_p->ie_id) {
 596
 597         case FR_LMI_ANSI_REPORT_TYPE_IE: /* fall through */
 598         case FR_LMI_CCITT_REPORT_TYPE_IE:
 599             if (vflag)
 600                 printf("%s (%u)",
 601                        tok2str(fr_lmi_report_type_ie_values,"unknown",p[2]),
 602                        p[2]);
 603             return 1;
 604
 605         case FR_LMI_ANSI_LINK_VERIFY_IE: /* fall through */
 606         case FR_LMI_CCITT_LINK_VERIFY_IE:
 607         case FR_LMI_ANSI_LINK_VERIFY_IE_91:
 608             if (!vflag)
 609                 printf(", ");
 610             printf("TX Seq: %3d, RX Seq: %3d", p[2], p[3]);
 611             return 1;
 612
 613         case FR_LMI_ANSI_PVC_STATUS_IE: /* fall through */
 614         case FR_LMI_CCITT_PVC_STATUS_IE:
 615             if (!vflag)
 616                 printf(", ");
 617             /* now parse the DLCI information element. */
 618             if ((ie_p->ie_len < 3) ||
 619                 (p[2] & 0x80) ||
 620                 ((ie_p->ie_len == 3) && !(p[3] & 0x80)) ||
 621                 ((ie_p->ie_len == 4) && ((p[3] & 0x80) || !(p[4] & 0x80))) ||
 622                 ((ie_p->ie_len == 5) && ((p[3] & 0x80) || (p[4] & 0x80) ||
 623                                    !(p[5] & 0x80))) ||
 624                 (ie_p->ie_len > 5) ||
 625                 !(p[ie_p->ie_len + 1] & 0x80))
 626                 printf("Invalid DLCI IE");
 627
 628             dlci = ((p[2] & 0x3F) << 4) | ((p[3] & 0x78) >> 3);
 629             if (ie_p->ie_len == 4)
 630                 dlci = (dlci << 6) | ((p[4] & 0x7E) >> 1);
 631             else if (ie_p->ie_len == 5)
 632                 dlci = (dlci << 13) | (p[4] & 0x7F) | ((p[5] & 0x7E) >> 1);
 633
 634             printf("DLCI %u: status %s%s", dlci,
 635                     p[ie_p->ie_len + 1] & 0x8 ? "New, " : "",
 636                     p[ie_p->ie_len + 1] & 0x2 ? "Active" : "Inactive");
 637             return 1;
 638         }
 639
 640         return 0;
 641 }