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

   1 /* Copyright (c) 2001 NETLAB, Temple University
   2  * Copyright (c) 2001 Protocol Engineering Lab, University of Delaware
   3  *
   4  * Jerry Heinz <gheinz@astro.temple.edu>
   5  * John Fiore <jfiore@joda.cis.temple.edu>
   6  * Armando L. Caro Jr. <acaro@cis.udel.edu>
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * 3. Neither the name of the University nor of the Laboratory may be used
  20  *    to endorse or promote products derived from this software without
  21  *    specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 /* \summary: Stream Control Transmission Protocol (SCTP) printer */
  37
  38 #ifdef HAVE_CONFIG_H
  39 #include "config.h"
  40 #endif
  41
  42 #include <netdissect-stdinc.h>
  43
  44 #include "netdissect.h"
  45 #include "addrtoname.h"
  46 #include "extract.h"
  47 #include "ip.h"
  48 #include "ip6.h"
  49
  50 /* Definitions from:
  51  *
  52  * SCTP reference Implementation Copyright (C) 1999 Cisco And Motorola
  53  *
  54  * Redistribution and use in source and binary forms, with or without
  55  * modification, are permitted provided that the following conditions
  56  * are met:
  57  *
  58  * 1. Redistributions of source code must retain the above copyright
  59  *    notice, this list of conditions and the following disclaimer.
  60  *
  61  * 2. Redistributions in binary form must reproduce the above copyright
  62  *    notice, this list of conditions and the following disclaimer in the
  63  *    documentation and/or other materials provided with the distribution.
  64  *
  65  * 3. Neither the name of Cisco nor of Motorola may be used
  66  *    to endorse or promote products derived from this software without
  67  *    specific prior written permission.
  68  *
  69  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  70  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  71  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  72  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  73  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  74  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  75  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  76  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  77  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  78  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  79  * SUCH DAMAGE.
  80  *
  81  * This file is part of the SCTP reference Implementation
  82  *
  83  *
  84  * Please send any bug reports or fixes you make to one of the following email
  85  * addresses:
  86  *
  87  * rstewar1@email.mot.com
  88  * kmorneau@cisco.com
  89  * qxie1@email.mot.com
  90  *
  91  * Any bugs reported given to us we will try to fix... any fixes shared will
  92  * be incorperated into the next SCTP release.
  93  */
  94
  95 /* The valid defines for all message
  96  * types know to SCTP. 0 is reserved
  97  */
  98 #define SCTP_DATA               0x00
  99 #define SCTP_INITIATION         0x01
 100 #define SCTP_INITIATION_ACK     0x02
 101 #define SCTP_SELECTIVE_ACK      0x03
 102 #define SCTP_HEARTBEAT_REQUEST  0x04
 103 #define SCTP_HEARTBEAT_ACK      0x05
 104 #define SCTP_ABORT_ASSOCIATION  0x06
 105 #define SCTP_SHUTDOWN           0x07
 106 #define SCTP_SHUTDOWN_ACK       0x08
 107 #define SCTP_OPERATION_ERR      0x09
 108 #define SCTP_COOKIE_ECHO        0x0a
 109 #define SCTP_COOKIE_ACK         0x0b
 110 #define SCTP_ECN_ECHO           0x0c
 111 #define SCTP_ECN_CWR            0x0d
 112 #define SCTP_SHUTDOWN_COMPLETE  0x0e
 113 #define SCTP_FORWARD_CUM_TSN    0xc0
 114 #define SCTP_RELIABLE_CNTL      0xc1
 115 #define SCTP_RELIABLE_CNTL_ACK  0xc2
 116
 117 static const struct tok sctp_chunkid_str[] = {
 118         { SCTP_DATA,              "DATA"              },
 119         { SCTP_INITIATION,        "INIT"              },
 120         { SCTP_INITIATION_ACK,    "INIT ACK"          },
 121         { SCTP_SELECTIVE_ACK,     "SACK"              },
 122         { SCTP_HEARTBEAT_REQUEST, "HB REQ"            },
 123         { SCTP_HEARTBEAT_ACK,     "HB ACK"            },
 124         { SCTP_ABORT_ASSOCIATION, "ABORT"             },
 125         { SCTP_SHUTDOWN,          "SHUTDOWN"          },
 126         { SCTP_SHUTDOWN_ACK,      "SHUTDOWN ACK"      },
 127         { SCTP_OPERATION_ERR,     "OP ERR"            },
 128         { SCTP_COOKIE_ECHO,       "COOKIE ECHO"       },
 129         { SCTP_COOKIE_ACK,        "COOKIE ACK"        },
 130         { SCTP_ECN_ECHO,          "ECN ECHO"          },
 131         { SCTP_ECN_CWR,           "ECN CWR"           },
 132         { SCTP_SHUTDOWN_COMPLETE, "SHUTDOWN COMPLETE" },
 133         { SCTP_FORWARD_CUM_TSN,   "FOR CUM TSN"       },
 134         { SCTP_RELIABLE_CNTL,     "REL CTRL"          },
 135         { SCTP_RELIABLE_CNTL_ACK, "REL CTRL ACK"      },
 136         { 0, NULL }
 137 };
 138
 139 /* Data Chuck Specific Flags */
 140 #define SCTP_DATA_FRAG_MASK     0x03
 141 #define SCTP_DATA_MIDDLE_FRAG   0x00
 142 #define SCTP_DATA_LAST_FRAG     0x01
 143 #define SCTP_DATA_FIRST_FRAG    0x02
 144 #define SCTP_DATA_NOT_FRAG      0x03
 145 #define SCTP_DATA_UNORDERED     0x04
 146
 147 #define SCTP_ADDRMAX 60
 148
 149 #define CHAN_HP 6704
 150 #define CHAN_MP 6705
 151 #define CHAN_LP 6706
 152
 153 /* the sctp common header */
 154
 155 struct sctpHeader{
 156   nd_uint16_t source;
 157   nd_uint16_t destination;
 158   nd_uint32_t verificationTag;
 159   nd_uint32_t adler32;
 160 };
 161
 162 /* various descriptor parsers */
 163
 164 struct sctpChunkDesc{
 165   nd_uint8_t  chunkID;
 166   nd_uint8_t  chunkFlg;
 167   nd_uint16_t chunkLength;
 168 };
 169
 170 struct sctpParamDesc{
 171   nd_uint16_t paramType;
 172   nd_uint16_t paramLength;
 173 };
 174
 175
 176 struct sctpRelChunkDesc{
 177   struct sctpChunkDesc chk;
 178   nd_uint32_t serialNumber;
 179 };
 180
 181 struct sctpVendorSpecificParam {
 182   struct sctpParamDesc p;  /* type must be 0xfffe */
 183   nd_uint32_t vendorId;    /* vendor ID from RFC 1700 */
 184   nd_uint16_t vendorSpecificType;
 185   nd_uint16_t vendorSpecificLen;
 186 };
 187
 188
 189 /* Structures for the control parts */
 190
 191
 192
 193 /* Sctp association init request/ack */
 194
 195 /* this is used for init ack, too */
 196 struct sctpInitiation{
 197   nd_uint32_t initTag;                  /* tag of mine */
 198   nd_uint32_t rcvWindowCredit;          /* rwnd */
 199   nd_uint16_t NumPreopenStreams;        /* OS */
 200   nd_uint16_t MaxInboundStreams;        /* MIS */
 201   nd_uint32_t initialTSN;
 202   /* optional param's follow in sctpParamDesc form */
 203 };
 204
 205 struct sctpV4IpAddress{
 206   struct sctpParamDesc p;       /* type is set to SCTP_IPV4_PARAM_TYPE, len=10 */
 207   nd_ipv4  ipAddress;
 208 };
 209
 210
 211 struct sctpV6IpAddress{
 212   struct sctpParamDesc p;       /* type is set to SCTP_IPV6_PARAM_TYPE, len=22 */
 213   nd_ipv6  ipAddress;
 214 };
 215
 216 struct sctpDNSName{
 217   struct sctpParamDesc param;
 218   nd_byte name[1];
 219 };
 220
 221
 222 struct sctpCookiePreserve{
 223   struct sctpParamDesc p;       /* type is set to SCTP_COOKIE_PRESERVE, len=8 */
 224   nd_uint32_t extraTime;
 225 };
 226
 227
 228 struct sctpTimeStamp{
 229   nd_uint32_t ts_sec;
 230   nd_uint32_t ts_usec;
 231 };
 232
 233
 234 /* this guy is for use when
 235  * I have a initiate message gloming the
 236  * things together.
 237
 238  */
 239 struct sctpUnifiedInit{
 240   struct sctpChunkDesc uh;
 241   struct sctpInitiation initm;
 242 };
 243
 244 struct sctpSendableInit{
 245   struct sctpHeader mh;
 246   struct sctpUnifiedInit msg;
 247 };
 248
 249
 250 /* Selective Acknowledgement
 251  * has the following structure with
 252  * a optional ammount of trailing int's
 253  * on the last part (based on the numberOfDesc
 254  * field).
 255  */
 256
 257 struct sctpSelectiveAck{
 258   nd_uint32_t highestConseqTSN;
 259   nd_uint32_t updatedRwnd;
 260   nd_uint16_t numberOfdesc;
 261   nd_uint16_t numDupTsns;
 262 };
 263
 264 struct sctpSelectiveFrag{
 265   nd_uint16_t fragmentStart;
 266   nd_uint16_t fragmentEnd;
 267 };
 268
 269
 270 struct sctpUnifiedSack{
 271   struct sctpChunkDesc uh;
 272   struct sctpSelectiveAck sack;
 273 };
 274
 275 /* for the abort and shutdown ACK
 276  * we must carry the init tag in the common header. Just the
 277  * common header is all that is needed with a chunk descriptor.
 278  */
 279 struct sctpUnifiedAbort{
 280   struct sctpChunkDesc uh;
 281 };
 282
 283 struct sctpUnifiedAbortLight{
 284   struct sctpHeader mh;
 285   struct sctpChunkDesc uh;
 286 };
 287
 288 struct sctpUnifiedAbortHeavy{
 289   struct sctpHeader mh;
 290   struct sctpChunkDesc uh;
 291   nd_uint16_t causeCode;
 292   nd_uint16_t causeLen;
 293 };
 294
 295 /* For the graceful shutdown we must carry
 296  * the tag (in common header)  and the highest consequitive acking value
 297  */
 298 struct sctpShutdown {
 299   nd_uint32_t TSN_Seen;
 300 };
 301
 302 struct sctpUnifiedShutdown{
 303   struct sctpChunkDesc uh;
 304   struct sctpShutdown shut;
 305 };
 306
 307 /* in the unified message we add the trailing
 308  * stream id since it is the only message
 309  * that is defined as a operation error.
 310  */
 311 struct sctpOpErrorCause{
 312   nd_uint16_t cause;
 313   nd_uint16_t causeLen;
 314 };
 315
 316 struct sctpUnifiedOpError{
 317   struct sctpChunkDesc uh;
 318   struct sctpOpErrorCause c;
 319 };
 320
 321 struct sctpUnifiedStreamError{
 322   struct sctpHeader mh;
 323   struct sctpChunkDesc uh;
 324   struct sctpOpErrorCause c;
 325   nd_uint16_t strmNum;
 326   nd_uint16_t reserved;
 327 };
 328
 329 struct staleCookieMsg{
 330   struct sctpHeader mh;
 331   struct sctpChunkDesc uh;
 332   struct sctpOpErrorCause c;
 333   nd_uint32_t moretime;
 334 };
 335
 336 /* the following is used in all sends
 337  * where nothing is needed except the
 338  * chunk/type i.e. shutdownAck Abort */
 339
 340 struct sctpUnifiedSingleMsg{
 341   struct sctpHeader mh;
 342   struct sctpChunkDesc uh;
 343 };
 344
 345 struct sctpDataPart{
 346   nd_uint32_t TSN;
 347   nd_uint16_t streamId;
 348   nd_uint16_t sequence;
 349   nd_uint32_t payloadtype;
 350 };
 351
 352 struct sctpUnifiedDatagram{
 353   struct sctpChunkDesc uh;
 354   struct sctpDataPart dp;
 355 };
 356
 357 struct sctpECN_echo{
 358   struct sctpChunkDesc uh;
 359   nd_uint32_t Lowest_TSN;
 360 };
 361
 362
 363 struct sctpCWR{
 364   struct sctpChunkDesc uh;
 365   nd_uint32_t TSN_reduced_at;
 366 };
 367
 368 static const struct tok ForCES_channels[] = {
 369         { CHAN_HP, "ForCES HP" },
 370         { CHAN_MP, "ForCES MP" },
 371         { CHAN_LP, "ForCES LP" },
 372         { 0, NULL }
 373 };
 374
 375 /* data chunk's payload protocol identifiers */
 376
 377 #define SCTP_PPID_IUA 1
 378 #define SCTP_PPID_M2UA 2
 379 #define SCTP_PPID_M3UA 3
 380 #define SCTP_PPID_SUA 4
 381 #define SCTP_PPID_M2PA 5
 382 #define SCTP_PPID_V5UA 6
 383 #define SCTP_PPID_H248 7
 384 #define SCTP_PPID_BICC 8
 385 #define SCTP_PPID_TALI 9
 386 #define SCTP_PPID_DUA 10
 387 #define SCTP_PPID_ASAP 11
 388 #define SCTP_PPID_ENRP 12
 389 #define SCTP_PPID_H323 13
 390 #define SCTP_PPID_QIPC 14
 391 #define SCTP_PPID_SIMCO 15
 392 #define SCTP_PPID_DDPSC 16
 393 #define SCTP_PPID_DDPSSC 17
 394 #define SCTP_PPID_S1AP 18
 395 #define SCTP_PPID_RUA 19
 396 #define SCTP_PPID_HNBAP 20
 397 #define SCTP_PPID_FORCES_HP 21
 398 #define SCTP_PPID_FORCES_MP 22
 399 #define SCTP_PPID_FORCES_LP 23
 400 #define SCTP_PPID_SBC_AP 24
 401 #define SCTP_PPID_NBAP 25
 402 /* 26 */
 403 #define SCTP_PPID_X2AP 27
 404
 405 static const struct tok PayloadProto_idents[] = {
 406         { SCTP_PPID_IUA,    "ISDN Q.921" },
 407         { SCTP_PPID_M2UA,   "M2UA"   },
 408         { SCTP_PPID_M3UA,   "M3UA"   },
 409         { SCTP_PPID_SUA,    "SUA"    },
 410         { SCTP_PPID_M2PA,   "M2PA"   },
 411         { SCTP_PPID_V5UA,   "V5.2"   },
 412         { SCTP_PPID_H248,   "H.248"  },
 413         { SCTP_PPID_BICC,   "BICC"   },
 414         { SCTP_PPID_TALI,   "TALI"   },
 415         { SCTP_PPID_DUA,    "DUA"    },
 416         { SCTP_PPID_ASAP,   "ASAP"   },
 417         { SCTP_PPID_ENRP,   "ENRP"   },
 418         { SCTP_PPID_H323,   "H.323"  },
 419         { SCTP_PPID_QIPC,   "Q.IPC"  },
 420         { SCTP_PPID_SIMCO,  "SIMCO"  },
 421         { SCTP_PPID_DDPSC,  "DDPSC"  },
 422         { SCTP_PPID_DDPSSC, "DDPSSC" },
 423         { SCTP_PPID_S1AP,   "S1AP"   },
 424         { SCTP_PPID_RUA,    "RUA"    },
 425         { SCTP_PPID_HNBAP,  "HNBAP"  },
 426         { SCTP_PPID_FORCES_HP, "ForCES HP" },
 427         { SCTP_PPID_FORCES_MP, "ForCES MP" },
 428         { SCTP_PPID_FORCES_LP, "ForCES LP" },
 429         { SCTP_PPID_SBC_AP, "SBc-AP" },
 430         { SCTP_PPID_NBAP,   "NBAP"   },
 431         /* 26 */
 432         { SCTP_PPID_X2AP,   "X2AP"   },
 433         { 0, NULL }
 434 };
 435
 436
 437 static inline int isForCES_port(u_short Port)
 438 {
 439         if (Port == CHAN_HP)
 440                 return 1;
 441         if (Port == CHAN_MP)
 442                 return 1;
 443         if (Port == CHAN_LP)
 444                 return 1;
 445
 446         return 0;
 447 }
 448
 449 void
 450 sctp_print(netdissect_options *ndo,
 451            const u_char *bp,        /* beginning of sctp packet */
 452            const u_char *bp2,       /* beginning of enclosing */
 453            u_int sctpPacketLength)  /* ip packet */
 454 {
 455   u_int sctpPacketLengthRemaining;
 456   const struct sctpHeader *sctpPktHdr;
 457   const struct ip *ip;
 458   const struct ip6_hdr *ip6;
 459   uint8_t chunkID;
 460   u_short sourcePort, destPort;
 461   u_int chunkCount;
 462   const struct sctpChunkDesc *chunkDescPtr;
 463   const char *sep;
 464   int isforces = 0;
 465
 466   if (sctpPacketLength < sizeof(struct sctpHeader))
 467     {
 468       ND_PRINT("truncated-sctp - %ld bytes missing!",
 469                    (long)(sizeof(struct sctpHeader) - sctpPacketLength));
 470       return;
 471     }
 472   sctpPktHdr = (const struct sctpHeader*) bp;
 473   ND_TCHECK_SIZE(sctpPktHdr);
 474   sctpPacketLengthRemaining = sctpPacketLength;
 475
 476   sourcePort = EXTRACT_BE_U_2(sctpPktHdr->source);
 477   destPort = EXTRACT_BE_U_2(sctpPktHdr->destination);
 478
 479   ip = (const struct ip *)bp2;
 480   if (IP_V(ip) == 6)
 481     ip6 = (const struct ip6_hdr *)bp2;
 482   else
 483     ip6 = NULL;
 484
 485   if (ip6) {
 486     ND_PRINT("%s.%u > %s.%u: sctp",
 487       ip6addr_string(ndo, &ip6->ip6_src),
 488       sourcePort,
 489       ip6addr_string(ndo, &ip6->ip6_dst),
 490       destPort);
 491   } else
 492   {
 493     ND_PRINT("%s.%u > %s.%u: sctp",
 494       ipaddr_string(ndo, &ip->ip_src),
 495       sourcePort,
 496       ipaddr_string(ndo, &ip->ip_dst),
 497       destPort);
 498   }
 499
 500   if (isForCES_port(sourcePort)) {
 501          ND_PRINT("[%s]", tok2str(ForCES_channels, NULL, sourcePort));
 502          isforces = 1;
 503   }
 504   if (isForCES_port(destPort)) {
 505          ND_PRINT("[%s]", tok2str(ForCES_channels, NULL, destPort));
 506          isforces = 1;
 507   }
 508
 509   bp += sizeof(struct sctpHeader);
 510   sctpPacketLengthRemaining -= sizeof(struct sctpHeader);
 511
 512   if (ndo->ndo_vflag >= 2)
 513     sep = "\n\t";
 514   else
 515     sep = " (";
 516   /* cycle through all chunks, printing information on each one */
 517   for (chunkCount = 0, chunkDescPtr = (const struct sctpChunkDesc *)bp;
 518       sctpPacketLengthRemaining != 0;
 519       chunkCount++)
 520     {
 521       uint16_t chunkLength, chunkLengthRemaining;
 522       uint16_t align;
 523
 524       chunkDescPtr = (const struct sctpChunkDesc *)bp;
 525       if (sctpPacketLengthRemaining < sizeof(*chunkDescPtr)) {
 526         ND_PRINT("%s%u) [chunk descriptor cut off at end of packet]", sep, chunkCount+1);
 527         break;
 528       }
 529       ND_TCHECK_SIZE(chunkDescPtr);
 530       chunkLength = EXTRACT_BE_U_2(chunkDescPtr->chunkLength);
 531       if (chunkLength < sizeof(*chunkDescPtr)) {
 532         ND_PRINT("%s%u) [Bad chunk length %u, < size of chunk descriptor]", sep, chunkCount+1, chunkLength);
 533         break;
 534       }
 535       chunkLengthRemaining = chunkLength;
 536
 537       align = chunkLength % 4;
 538       if (align != 0)
 539         align = 4 - align;
 540
 541       if (sctpPacketLengthRemaining < align) {
 542         ND_PRINT("%s%u) [Bad chunk length %u, > remaining data in packet]", sep, chunkCount+1, chunkLength);
 543         break;
 544       }
 545
 546       ND_TCHECK_LEN(bp, chunkLength);
 547
 548       bp += sizeof(*chunkDescPtr);
 549       sctpPacketLengthRemaining -= sizeof(*chunkDescPtr);
 550       chunkLengthRemaining -= sizeof(*chunkDescPtr);
 551
 552       ND_PRINT("%s%u) ", sep, chunkCount+1);
 553       chunkID = EXTRACT_U_1(chunkDescPtr->chunkID);
 554       ND_PRINT("[%s] ", tok2str(sctp_chunkid_str, "Unknown chunk type: 0x%x",
 555                                       chunkID));
 556       switch (chunkID)
 557         {
 558         case SCTP_DATA :
 559           {
 560             const struct sctpDataPart *dataHdrPtr;
 561             uint8_t chunkFlg;
 562             uint32_t ppid;
 563             u_int payload_size;
 564
 565             chunkFlg = EXTRACT_U_1(chunkDescPtr->chunkFlg);
 566             if ((chunkFlg & SCTP_DATA_UNORDERED) == SCTP_DATA_UNORDERED)
 567               ND_PRINT("(U)");
 568
 569             if ((chunkFlg & SCTP_DATA_FIRST_FRAG) == SCTP_DATA_FIRST_FRAG)
 570               ND_PRINT("(B)");
 571
 572             if ((chunkFlg & SCTP_DATA_LAST_FRAG) == SCTP_DATA_LAST_FRAG)
 573               ND_PRINT("(E)");
 574
 575             if( ((chunkFlg & SCTP_DATA_UNORDERED) == SCTP_DATA_UNORDERED) ||
 576                 ((chunkFlg & SCTP_DATA_FIRST_FRAG) == SCTP_DATA_FIRST_FRAG) ||
 577                 ((chunkFlg & SCTP_DATA_LAST_FRAG) == SCTP_DATA_LAST_FRAG) )
 578               ND_PRINT(" ");
 579
 580             if (chunkLengthRemaining < sizeof(*dataHdrPtr)) {
 581                 ND_PRINT("bogus chunk length %u]", chunkLength);
 582                 return;
 583             }
 584             dataHdrPtr=(const struct sctpDataPart*)bp;
 585
 586             ppid = EXTRACT_BE_U_4(dataHdrPtr->payloadtype);
 587             ND_PRINT("[TSN: %u] ", EXTRACT_BE_U_4(dataHdrPtr->TSN));
 588             ND_PRINT("[SID: %u] ", EXTRACT_BE_U_2(dataHdrPtr->streamId));
 589             ND_PRINT("[SSEQ %u] ", EXTRACT_BE_U_2(dataHdrPtr->sequence));
 590             ND_PRINT("[PPID %s] ",
 591                     tok2str(PayloadProto_idents, "0x%x", ppid));
 592
 593             if (!isforces) {
 594                 isforces = (ppid == SCTP_PPID_FORCES_HP) ||
 595                     (ppid == SCTP_PPID_FORCES_MP) ||
 596                     (ppid == SCTP_PPID_FORCES_LP);
 597             }
 598
 599             bp += sizeof(*dataHdrPtr);
 600             sctpPacketLengthRemaining -= sizeof(*dataHdrPtr);
 601             chunkLengthRemaining -= sizeof(*dataHdrPtr);
 602             payload_size = chunkLengthRemaining;
 603             if (payload_size == 0) {
 604                 ND_PRINT("bogus chunk length %u]", chunkLength);
 605                 return;
 606             }
 607
 608             if (isforces) {
 609                 forces_print(ndo, bp, payload_size);
 610             } else if (ndo->ndo_vflag >= 2) {   /* if verbose output is specified */
 611                                         /* at the command line */
 612                 switch (ppid) {
 613                 case SCTP_PPID_M3UA :
 614                         m3ua_print(ndo, bp, payload_size);
 615                         break;
 616                 default:
 617                         ND_PRINT("[Payload");
 618                         if (!ndo->ndo_suppress_default_print) {
 619                                 ND_PRINT(":");
 620                                 ND_DEFAULTPRINT(bp, payload_size);
 621                         }
 622                         ND_PRINT("]");
 623                         break;
 624                 }
 625             }
 626             bp += payload_size;
 627             sctpPacketLengthRemaining -= payload_size;
 628             chunkLengthRemaining -= payload_size;
 629             break;
 630           }
 631         case SCTP_INITIATION :
 632           {
 633             const struct sctpInitiation *init;
 634
 635             if (chunkLengthRemaining < sizeof(*init)) {
 636                 ND_PRINT("bogus chunk length %u]", chunkLength);
 637                 return;
 638             }
 639             init=(const struct sctpInitiation*)bp;
 640             ND_PRINT("[init tag: %u] ", EXTRACT_BE_U_4(init->initTag));
 641             ND_PRINT("[rwnd: %u] ", EXTRACT_BE_U_4(init->rcvWindowCredit));
 642             ND_PRINT("[OS: %u] ", EXTRACT_BE_U_2(init->NumPreopenStreams));
 643             ND_PRINT("[MIS: %u] ", EXTRACT_BE_U_2(init->MaxInboundStreams));
 644             ND_PRINT("[init TSN: %u] ", EXTRACT_BE_U_4(init->initialTSN));
 645             bp += sizeof(*init);
 646             sctpPacketLengthRemaining -= sizeof(*init);
 647             chunkLengthRemaining -= sizeof(*init);
 648
 649 #if 0 /* ALC you can add code for optional params here */
 650             if( chunkLengthRemaining != 0 )
 651               ND_PRINT(" @@@@@ UNFINISHED @@@@@@%s\n",
 652                      "Optional params present, but not printed.");
 653 #endif
 654             bp += chunkLengthRemaining;
 655             sctpPacketLengthRemaining -= chunkLengthRemaining;
 656             chunkLengthRemaining = 0;
 657             break;
 658           }
 659         case SCTP_INITIATION_ACK :
 660           {
 661             const struct sctpInitiation *init;
 662
 663             if (chunkLengthRemaining < sizeof(*init)) {
 664                 ND_PRINT("bogus chunk length %u]", chunkLength);
 665                 return;
 666             }
 667             init=(const struct sctpInitiation*)bp;
 668             ND_PRINT("[init tag: %u] ", EXTRACT_BE_U_4(init->initTag));
 669             ND_PRINT("[rwnd: %u] ", EXTRACT_BE_U_4(init->rcvWindowCredit));
 670             ND_PRINT("[OS: %u] ", EXTRACT_BE_U_2(init->NumPreopenStreams));
 671             ND_PRINT("[MIS: %u] ", EXTRACT_BE_U_2(init->MaxInboundStreams));
 672             ND_PRINT("[init TSN: %u] ", EXTRACT_BE_U_4(init->initialTSN));
 673             bp += sizeof(*init);
 674             sctpPacketLengthRemaining -= sizeof(*init);
 675             chunkLengthRemaining -= sizeof(*init);
 676
 677 #if 0 /* ALC you can add code for optional params here */
 678             if( chunkLengthRemaining != 0 )
 679               ND_PRINT(" @@@@@ UNFINISHED @@@@@@%s\n",
 680                      "Optional params present, but not printed.");
 681 #endif
 682             bp += chunkLengthRemaining;
 683             sctpPacketLengthRemaining -= chunkLengthRemaining;
 684             chunkLengthRemaining = 0;
 685             break;
 686           }
 687         case SCTP_SELECTIVE_ACK:
 688           {
 689             const struct sctpSelectiveAck *sack;
 690             const struct sctpSelectiveFrag *frag;
 691             u_int fragNo, tsnNo;
 692             const u_char *dupTSN;
 693
 694             if (chunkLengthRemaining < sizeof(*sack)) {
 695               ND_PRINT("bogus chunk length %u]", chunkLength);
 696               return;
 697             }
 698             sack=(const struct sctpSelectiveAck*)bp;
 699             ND_PRINT("[cum ack %u] ", EXTRACT_BE_U_4(sack->highestConseqTSN));
 700             ND_PRINT("[a_rwnd %u] ", EXTRACT_BE_U_4(sack->updatedRwnd));
 701             ND_PRINT("[#gap acks %u] ", EXTRACT_BE_U_2(sack->numberOfdesc));
 702             ND_PRINT("[#dup tsns %u] ", EXTRACT_BE_U_2(sack->numDupTsns));
 703             bp += sizeof(*sack);
 704             sctpPacketLengthRemaining -= sizeof(*sack);
 705             chunkLengthRemaining -= sizeof(*sack);
 706
 707
 708             /* print gaps */
 709             for (fragNo=0;
 710                  chunkLengthRemaining != 0 && fragNo < EXTRACT_BE_U_2(sack->numberOfdesc);
 711                  bp += sizeof(*frag), sctpPacketLengthRemaining -= sizeof(*frag), chunkLengthRemaining -= sizeof(*frag), fragNo++) {
 712               if (chunkLengthRemaining < sizeof(*frag)) {
 713                 ND_PRINT("bogus chunk length %u]", chunkLength);
 714                 return;
 715               }
 716               frag = (const struct sctpSelectiveFrag *)bp;
 717               ND_PRINT("\n\t\t[gap ack block #%u: start = %u, end = %u] ",
 718                      fragNo+1,
 719                      EXTRACT_BE_U_4(sack->highestConseqTSN) + EXTRACT_BE_U_2(frag->fragmentStart),
 720                      EXTRACT_BE_U_4(sack->highestConseqTSN) + EXTRACT_BE_U_2(frag->fragmentEnd));
 721             }
 722
 723             /* print duplicate TSNs */
 724             for (tsnNo=0;
 725                  chunkLengthRemaining != 0 && tsnNo<EXTRACT_BE_U_2(sack->numDupTsns);
 726                  bp += 4, sctpPacketLengthRemaining -= 4, chunkLengthRemaining -= 4, tsnNo++) {
 727               if (chunkLengthRemaining < 4) {
 728                 ND_PRINT("bogus chunk length %u]", chunkLength);
 729                 return;
 730               }
 731               dupTSN = (const u_char *)bp;
 732               ND_PRINT("\n\t\t[dup TSN #%u: %u] ", tsnNo+1,
 733                 EXTRACT_BE_U_4(dupTSN));
 734             }
 735             break;
 736           }
 737         default :
 738           {
 739             bp += chunkLengthRemaining;
 740             sctpPacketLengthRemaining -= chunkLengthRemaining;
 741             chunkLengthRemaining = 0;
 742             break;
 743           }
 744         }
 745
 746       /*
 747        * Any extra stuff at the end of the chunk?
 748        * XXX - report this?
 749        */
 750       bp += chunkLengthRemaining;
 751       sctpPacketLengthRemaining -= chunkLengthRemaining;
 752
 753       if (ndo->ndo_vflag < 2)
 754         sep = ", (";
 755
 756       if (align != 0) {
 757         /*
 758          * Fail if the alignment padding isn't in the captured data.
 759          * Otherwise, skip it.
 760          */
 761         ND_TCHECK_LEN(bp, align);
 762         bp += align;
 763         sctpPacketLengthRemaining -= align;
 764       }
 765     }
 766     return;
 767
 768 trunc:
 769     ND_PRINT("[|sctp]");
 770 }