print-sctp.c

/* Copyright (c) 2001 NETLAB, Temple University
 * Copyright (c) 2001 Protocol Engineering Lab, University of Delaware
 *
 * Jerry Heinz <gheinz@astro.temple.edu>
 * John Fiore <jfiore@joda.cis.temple.edu>
 * Armando L. Caro Jr. <acaro@cis.udel.edu>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <tcpdump-stdinc.h>

#include <assert.h>

#include <stdio.h>
#include <string.h>

#include "interface.h"
#include "addrtoname.h"
#include "extract.h"			/* must come after interface.h */
#include "ip.h"
#ifdef INET6
#include "ip6.h"
#endif

/* Definitions from:
 *
 * SCTP reference Implementation Copyright (C) 1999 Cisco And Motorola
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of Cisco nor of Motorola may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This file is part of the SCTP reference Implementation
 *
 *
 * Please send any bug reports or fixes you make to one of the following email
 * addresses:
 *
 * rstewar1@email.mot.com
 * kmorneau@cisco.com
 * qxie1@email.mot.com
 *
 * Any bugs reported given to us we will try to fix... any fixes shared will
 * be incorperated into the next SCTP release.
 */

/* The valid defines for all message
 * types know to SCTP. 0 is reserved
 */
#define SCTP_DATA		0x00
#define SCTP_INITIATION		0x01
#define SCTP_INITIATION_ACK	0x02
#define SCTP_SELECTIVE_ACK	0x03
#define SCTP_HEARTBEAT_REQUEST	0x04
#define SCTP_HEARTBEAT_ACK	0x05
#define SCTP_ABORT_ASSOCIATION	0x06
#define SCTP_SHUTDOWN		0x07
#define SCTP_SHUTDOWN_ACK	0x08
#define SCTP_OPERATION_ERR	0x09
#define SCTP_COOKIE_ECHO	0x0a
#define SCTP_COOKIE_ACK         0x0b
#define SCTP_ECN_ECHO		0x0c
#define SCTP_ECN_CWR		0x0d
#define SCTP_SHUTDOWN_COMPLETE	0x0e
#define SCTP_FORWARD_CUM_TSN    0xc0
#define SCTP_RELIABLE_CNTL      0xc1
#define SCTP_RELIABLE_CNTL_ACK  0xc2

/* Data Chuck Specific Flags */
#define SCTP_DATA_FRAG_MASK	0x03
#define SCTP_DATA_MIDDLE_FRAG	0x00
#define SCTP_DATA_LAST_FRAG	0x01
#define SCTP_DATA_FIRST_FRAG	0x02
#define SCTP_DATA_NOT_FRAG	0x03
#define SCTP_DATA_UNORDERED	0x04

#define SCTP_ADDRMAX 60

#define CHAN_HP 6704
#define CHAN_MP 6705
#define CHAN_LP 6706

/* the sctp common header */

struct sctpHeader{
  u_int16_t source;
  u_int16_t destination;
  u_int32_t verificationTag;
  u_int32_t adler32;
};

/* various descriptor parsers */

struct sctpChunkDesc{
  u_int8_t chunkID;
  u_int8_t chunkFlg;
  u_int16_t chunkLength;
};

struct sctpParamDesc{
  u_int16_t paramType;
  u_int16_t paramLength;
};


struct sctpRelChunkDesc{
  struct sctpChunkDesc chk;
  u_int32_t serialNumber;
};

struct sctpVendorSpecificParam {
  struct sctpParamDesc p;  /* type must be 0xfffe */
  u_int32_t vendorId;	   /* vendor ID from RFC 1700 */
  u_int16_t vendorSpecificType;
  u_int16_t vendorSpecificLen;
};


/* Structures for the control parts */



/* Sctp association init request/ack */

/* this is used for init ack, too */
struct sctpInitiation{
  u_int32_t initTag;		/* tag of mine */
  u_int32_t rcvWindowCredit;	/* rwnd */
  u_int16_t NumPreopenStreams;	/* OS */
  u_int16_t MaxInboundStreams;     /* MIS */
  u_int32_t initialTSN;
  /* optional param's follow in sctpParamDesc form */
};

struct sctpV4IpAddress{
  struct sctpParamDesc p;	/* type is set to SCTP_IPV4_PARAM_TYPE, len=10 */
  u_int32_t  ipAddress;
};


struct sctpV6IpAddress{
  struct sctpParamDesc p;	/* type is set to SCTP_IPV6_PARAM_TYPE, len=22 */
  u_int8_t  ipAddress[16];
};

struct sctpDNSName{
  struct sctpParamDesc param;
  u_int8_t name[1];
};


struct sctpCookiePreserve{
  struct sctpParamDesc p;	/* type is set to SCTP_COOKIE_PRESERVE, len=8 */
  u_int32_t extraTime;
};


struct sctpTimeStamp{
  u_int32_t ts_sec;
  u_int32_t ts_usec;
};

/* wire structure of my cookie */
struct cookieMessage{
  u_int32_t TieTag_curTag;		/* copied from assoc if present */
  u_int32_t TieTag_hisTag; 		/* copied from assoc if present */
  int32_t cookieLife;			/* life I will award this cookie */
  struct sctpTimeStamp timeEnteringState; /* the time I built cookie */
  struct sctpInitiation initAckISent;	/* the INIT-ACK that I sent to my peer */
  u_int32_t addressWhereISent[4];	/* I make this 4 ints so I get 128bits for future */
  int32_t addrtype;			/* address type */
  u_int16_t locScope;			/* V6 local scope flag */
  u_int16_t siteScope;			/* V6 site scope flag */
  /* at the end is tacked on the INIT chunk sent in
   * its entirety and of course our
   * signature.
   */
};


/* this guy is for use when
 * I have a initiate message gloming the
 * things together.

 */
struct sctpUnifiedInit{
  struct sctpChunkDesc uh;
  struct sctpInitiation initm;
};

struct sctpSendableInit{
  struct sctpHeader mh;
  struct sctpUnifiedInit msg;
};


/* Selective Acknowledgement
 * has the following structure with
 * a optional ammount of trailing int's
 * on the last part (based on the numberOfDesc
 * field).
 */

struct sctpSelectiveAck{
  u_int32_t highestConseqTSN;
  u_int32_t updatedRwnd;
  u_int16_t numberOfdesc;
  u_int16_t numDupTsns;
};

struct sctpSelectiveFrag{
  u_int16_t fragmentStart;
  u_int16_t fragmentEnd;
};


struct sctpUnifiedSack{
  struct sctpChunkDesc uh;
  struct sctpSelectiveAck sack;
};

/* for both RTT request/response the
 * following is sent
 */

struct sctpHBrequest {
  u_int32_t time_value_1;
  u_int32_t time_value_2;
};

/* here is what I read and respond with to. */
struct sctpHBunified{
  struct sctpChunkDesc hdr;
  struct sctpParamDesc hb;
};


/* here is what I send */
struct sctpHBsender{
  struct sctpChunkDesc hdr;
  struct sctpParamDesc hb;
  struct sctpHBrequest rtt;
  int8_t addrFmt[SCTP_ADDRMAX];
  u_int16_t userreq;
};



/* for the abort and shutdown ACK
 * we must carry the init tag in the common header. Just the
 * common header is all that is needed with a chunk descriptor.
 */
struct sctpUnifiedAbort{
  struct sctpChunkDesc uh;
};

struct sctpUnifiedAbortLight{
  struct sctpHeader mh;
  struct sctpChunkDesc uh;
};

struct sctpUnifiedAbortHeavy{
  struct sctpHeader mh;
  struct sctpChunkDesc uh;
  u_int16_t causeCode;
  u_int16_t causeLen;
};

/* For the graceful shutdown we must carry
 * the tag (in common header)  and the highest consequitive acking value
 */
struct sctpShutdown {
  u_int32_t TSN_Seen;
};

struct sctpUnifiedShutdown{
  struct sctpChunkDesc uh;
  struct sctpShutdown shut;
};

/* in the unified message we add the trailing
 * stream id since it is the only message
 * that is defined as a operation error.
 */
struct sctpOpErrorCause{
  u_int16_t cause;
  u_int16_t causeLen;
};

struct sctpUnifiedOpError{
  struct sctpChunkDesc uh;
  struct sctpOpErrorCause c;
};

struct sctpUnifiedStreamError{
  struct sctpHeader mh;
  struct sctpChunkDesc uh;
  struct sctpOpErrorCause c;
  u_int16_t strmNum;
  u_int16_t reserved;
};

struct staleCookieMsg{
  struct sctpHeader mh;
  struct sctpChunkDesc uh;
  struct sctpOpErrorCause c;
  u_int32_t moretime;
};

/* the following is used in all sends
 * where nothing is needed except the
 * chunk/type i.e. shutdownAck Abort */

struct sctpUnifiedSingleMsg{
  struct sctpHeader mh;
  struct sctpChunkDesc uh;
};

struct sctpDataPart{
  u_int32_t TSN;
  u_int16_t streamId;
  u_int16_t sequence;
  u_int32_t payloadtype;
};

struct sctpUnifiedDatagram{
  struct sctpChunkDesc uh;
  struct sctpDataPart dp;
};

struct sctpECN_echo{
  struct sctpChunkDesc uh;
  u_int32_t Lowest_TSN;
};


struct sctpCWR{
  struct sctpChunkDesc uh;
  u_int32_t TSN_reduced_at;
};

static const struct tok ForCES_channels[] = {
	{ CHAN_HP, "ForCES HP" },
	{ CHAN_MP, "ForCES MP" },
	{ CHAN_LP, "ForCES LP" },
	{ 0, NULL }
};

static inline int isForCES_port(u_short Port)
{
	if (Port == CHAN_HP)
		return 1;
	if (Port == CHAN_MP)
		return 1;
	if (Port == CHAN_LP)
		return 1;

	return 0;
}

void sctp_print(const u_char *bp,        /* beginning of sctp packet */
		const u_char *bp2,       /* beginning of enclosing */
		u_int sctpPacketLength)  /* ip packet */
{
  const struct sctpHeader *sctpPktHdr;
  const struct ip *ip;
#ifdef INET6
  const struct ip6_hdr *ip6;
#endif
  const void *endPacketPtr;
  u_short sourcePort, destPort;
  int chunkCount;
  const struct sctpChunkDesc *chunkDescPtr;
  const void *nextChunk;
  const char *sep;
  int isforces = 0;


  sctpPktHdr = (const struct sctpHeader*) bp;
  endPacketPtr = (const u_char*)sctpPktHdr+sctpPacketLength;

  if( (u_long) endPacketPtr > (u_long) snapend)
    endPacketPtr = (const void *) snapend;
  ip = (struct ip *)bp2;
#ifdef INET6
  if (IP_V(ip) == 6)
    ip6 = (const struct ip6_hdr *)bp2;
  else
    ip6 = NULL;
#endif /*INET6*/
  TCHECK(*sctpPktHdr);

  if (sctpPacketLength < sizeof(struct sctpHeader))
    {
      (void)printf("truncated-sctp - %ld bytes missing!",
		   (long)sctpPacketLength-sizeof(struct sctpHeader));
      return;
    }

  /*    sctpPacketLength -= sizeof(struct sctpHeader);  packet length  */
  /*  			      is now only as long as the payload  */

  sourcePort = EXTRACT_16BITS(&sctpPktHdr->source);
  destPort = EXTRACT_16BITS(&sctpPktHdr->destination);

#ifdef INET6
  if (ip6) {
    (void)printf("%s.%d > %s.%d: sctp",
      ip6addr_string(&ip6->ip6_src),
      sourcePort,
      ip6addr_string(&ip6->ip6_dst),
      destPort);
  } else
#endif /*INET6*/
  {
    (void)printf("%s.%d > %s.%d: sctp",
      ipaddr_string(&ip->ip_src),
      sourcePort,
      ipaddr_string(&ip->ip_dst),
      destPort);
  }
  fflush(stdout);

  if (isForCES_port(sourcePort)) {
         printf("[%s]", tok2str(ForCES_channels, NULL, sourcePort));
         isforces = 1;
  }
  if (isForCES_port(destPort)) {
         printf("[%s]", tok2str(ForCES_channels, NULL, destPort));
         isforces = 1;
  }

  if (vflag >= 2)
    sep = "\n\t";
  else
    sep = " (";
  /* cycle through all chunks, printing information on each one */
  for (chunkCount = 0,
	 chunkDescPtr = (const struct sctpChunkDesc *)
	    ((const u_char*) sctpPktHdr + sizeof(struct sctpHeader));
       chunkDescPtr != NULL &&
	 ( (const void *)
	    ((const u_char *) chunkDescPtr + sizeof(struct sctpChunkDesc))
	   <= endPacketPtr);

       chunkDescPtr = (const struct sctpChunkDesc *) nextChunk, chunkCount++)
    {
      u_int16_t chunkLength;
      const u_char *chunkEnd;
      u_int16_t align;

      TCHECK(*chunkDescPtr);
      chunkLength = EXTRACT_16BITS(&chunkDescPtr->chunkLength);
      if (chunkLength < sizeof(*chunkDescPtr)) {
      	printf("%s%d) [Bad chunk length %u]", sep, chunkCount+1, chunkLength);
      	break;
      }

      TCHECK2(*((u_int8_t *)chunkDescPtr), chunkLength);
      chunkEnd = ((const u_char*)chunkDescPtr + chunkLength);

      align=chunkLength % 4;
      if (align != 0)
	align = 4 - align;

      nextChunk = (const void *) (chunkEnd + align);

      printf("%s%d) ", sep, chunkCount+1);
      switch (chunkDescPtr->chunkID)
	{
	case SCTP_DATA :
	  {
	    const struct sctpDataPart *dataHdrPtr;

	    printf("[DATA] ");

	    if ((chunkDescPtr->chunkFlg & SCTP_DATA_UNORDERED)
		== SCTP_DATA_UNORDERED)
	      printf("(U)");

	    if ((chunkDescPtr->chunkFlg & SCTP_DATA_FIRST_FRAG)
		== SCTP_DATA_FIRST_FRAG)
	      printf("(B)");

	    if ((chunkDescPtr->chunkFlg & SCTP_DATA_LAST_FRAG)
		== SCTP_DATA_LAST_FRAG)
	      printf("(E)");

	    if( ((chunkDescPtr->chunkFlg & SCTP_DATA_UNORDERED)
		 == SCTP_DATA_UNORDERED)
		||
		((chunkDescPtr->chunkFlg & SCTP_DATA_FIRST_FRAG)
		 == SCTP_DATA_FIRST_FRAG)
		||
		((chunkDescPtr->chunkFlg & SCTP_DATA_LAST_FRAG)
		 == SCTP_DATA_LAST_FRAG) )
	      printf(" ");

	    dataHdrPtr=(const struct sctpDataPart*)(chunkDescPtr+1);

	    printf("[TSN: %u] ", EXTRACT_32BITS(&dataHdrPtr->TSN));
	    printf("[SID: %u] ", EXTRACT_16BITS(&dataHdrPtr->streamId));
	    printf("[SSEQ %u] ", EXTRACT_16BITS(&dataHdrPtr->sequence));
	    printf("[PPID 0x%x] ", EXTRACT_32BITS(&dataHdrPtr->payloadtype));
	    fflush(stdout);
	    if (isforces) {
		const u_char *payloadPtr;
		u_int chunksize = sizeof(struct sctpDataPart)+
			          sizeof(struct sctpChunkDesc);
		payloadPtr = (const u_char *) (dataHdrPtr + 1);
		if (EXTRACT_16BITS(&chunkDescPtr->chunkLength) <
			sizeof(struct sctpDataPart)+
			sizeof(struct sctpChunkDesc)+1) {
		/* Less than 1 byte of chunk payload */
			printf("bogus ForCES chunk length %u]",
			    EXTRACT_16BITS(&chunkDescPtr->chunkLength));
			return;
		}

		forces_print(payloadPtr, EXTRACT_16BITS(&chunkDescPtr->chunkLength)- chunksize);
	   } else if (vflag >= 2) {	/* if verbose output is specified */
					/* at the command line */
		const u_char *payloadPtr;

		printf("[Payload");

		if (!suppress_default_print) {
			payloadPtr = (const u_char *) (++dataHdrPtr);
			printf(":");
			if (EXTRACT_16BITS(&chunkDescPtr->chunkLength) <
			    sizeof(struct sctpDataPart)+
			    sizeof(struct sctpChunkDesc)+1) {
				/* Less than 1 byte of chunk payload */
				printf("bogus chunk length %u]",
				    EXTRACT_16BITS(&chunkDescPtr->chunkLength));
				return;
			}
			default_print(payloadPtr,
			      EXTRACT_16BITS(&chunkDescPtr->chunkLength) -
			      (sizeof(struct sctpDataPart)+
			      sizeof(struct sctpChunkDesc)));
		} else
			printf("]");
	      }
	    break;
	  }
	case SCTP_INITIATION :
	  {
	    const struct sctpInitiation *init;

	    printf("[INIT] ");
	    init=(const struct sctpInitiation*)(chunkDescPtr+1);
	    printf("[init tag: %u] ", EXTRACT_32BITS(&init->initTag));
	    printf("[rwnd: %u] ", EXTRACT_32BITS(&init->rcvWindowCredit));
	    printf("[OS: %u] ", EXTRACT_16BITS(&init->NumPreopenStreams));
	    printf("[MIS: %u] ", EXTRACT_16BITS(&init->MaxInboundStreams));
	    printf("[init TSN: %u] ", EXTRACT_32BITS(&init->initialTSN));

#if(0) /* ALC you can add code for optional params here */
	    if( (init+1) < chunkEnd )
	      printf(" @@@@@ UNFINISHED @@@@@@%s\n",
		     "Optional params present, but not printed.");
#endif
	    break;
	  }
	case SCTP_INITIATION_ACK :
	  {
	    const struct sctpInitiation *init;

	    printf("[INIT ACK] ");
	    init=(const struct sctpInitiation*)(chunkDescPtr+1);
	    printf("[init tag: %u] ", EXTRACT_32BITS(&init->initTag));
	    printf("[rwnd: %u] ", EXTRACT_32BITS(&init->rcvWindowCredit));
	    printf("[OS: %u] ", EXTRACT_16BITS(&init->NumPreopenStreams));
	    printf("[MIS: %u] ", EXTRACT_16BITS(&init->MaxInboundStreams));
	    printf("[init TSN: %u] ", EXTRACT_32BITS(&init->initialTSN));

#if(0) /* ALC you can add code for optional params here */
	    if( (init+1) < chunkEnd )
	      printf(" @@@@@ UNFINISHED @@@@@@%s\n",
		     "Optional params present, but not printed.");
#endif
	    break;
	  }
	case SCTP_SELECTIVE_ACK:
	  {
	    const struct sctpSelectiveAck *sack;
	    const struct sctpSelectiveFrag *frag;
	    int fragNo, tsnNo;
	    const u_char *dupTSN;

	    printf("[SACK] ");
	    sack=(const struct sctpSelectiveAck*)(chunkDescPtr+1);
	    printf("[cum ack %u] ", EXTRACT_32BITS(&sack->highestConseqTSN));
	    printf("[a_rwnd %u] ", EXTRACT_32BITS(&sack->updatedRwnd));
	    printf("[#gap acks %u] ", EXTRACT_16BITS(&sack->numberOfdesc));
	    printf("[#dup tsns %u] ", EXTRACT_16BITS(&sack->numDupTsns));


	    /* print gaps */
	    for (frag = ( (const struct sctpSelectiveFrag *)
			  ((const struct sctpSelectiveAck *) sack+1)),
		   fragNo=0;
		 (const void *)frag < nextChunk && fragNo < EXTRACT_16BITS(&sack->numberOfdesc);
		 frag++, fragNo++)
	      printf("\n\t\t[gap ack block #%d: start = %u, end = %u] ",
		     fragNo+1,
		     EXTRACT_32BITS(&sack->highestConseqTSN) + EXTRACT_16BITS(&frag->fragmentStart),
		     EXTRACT_32BITS(&sack->highestConseqTSN) + EXTRACT_16BITS(&frag->fragmentEnd));


	    /* print duplicate TSNs */
	    for (dupTSN = (const u_char *)frag, tsnNo=0;
		 (const void *) dupTSN < nextChunk && tsnNo<EXTRACT_16BITS(&sack->numDupTsns);
		 dupTSN += 4, tsnNo++)
	      printf("\n\t\t[dup TSN #%u: %u] ", tsnNo+1,
	          EXTRACT_32BITS(dupTSN));

	    break;
	  }
	case SCTP_HEARTBEAT_REQUEST :
	  printf("[HB REQ] ");
	  break;
	case SCTP_HEARTBEAT_ACK :
	  printf("[HB ACK] ");
	  break;
	case SCTP_ABORT_ASSOCIATION :
	  printf("[ABORT] ");
	  break;
	case SCTP_SHUTDOWN :
	  printf("[SHUTDOWN] ");
	  break;
	case SCTP_SHUTDOWN_ACK :
	  printf("[SHUTDOWN ACK] ");
	  break;
	case SCTP_OPERATION_ERR :
	  printf("[OP ERR] ");
	  break;
	case SCTP_COOKIE_ECHO :
	  printf("[COOKIE ECHO] ");
	  break;
	case SCTP_COOKIE_ACK :
	  printf("[COOKIE ACK] ");
	  break;
	case SCTP_ECN_ECHO :
	  printf("[ECN ECHO] ");
	  break;
	case SCTP_ECN_CWR :
	  printf("[ECN CWR] ");
	  break;
	case SCTP_SHUTDOWN_COMPLETE :
	  printf("[SHUTDOWN COMPLETE] ");
	  break;
	case SCTP_FORWARD_CUM_TSN :
	  printf("[FOR CUM TSN] ");
	  break;
	case SCTP_RELIABLE_CNTL :
	  printf("[REL CTRL] ");
	  break;
	case SCTP_RELIABLE_CNTL_ACK :
	  printf("[REL CTRL ACK] ");
	  break;
	default :
	  printf("[Unknown chunk type: 0x%x]", chunkDescPtr->chunkID);
	  return;
	}

	if (vflag < 2)
	  sep = ", (";
    }
    return;

trunc:
    printf("[|sctp]");
    return;
}