_token.c

This directory contains source code for tcpdump, a tool for network monitoring and data acquisition

/*
 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University nor the names of its contributors may be used to endorse
 * or promote products derived from this software without specific prior
 * written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Hacked version of print-ether.c  Larry Lile <[e-mail]>
 *
 * $FreeBSD: src/contrib/tcpdump/print-token.c,v 1.3 2000/01/30 01:00:54 fenner Exp $
 */

#if 0
static const char rcsid[] =
"@(#) $Header: /home/ncvs/src/contrib/tcpdump/print-token.c,v 1.1 1999/02/20 11:17:55 julian Exp $";
#endif

#include <stdio.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>

#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/tcp.h>
#include <netinet/tcpip.h>
#include <pcap.h>

#include "token.h"
#include "interfac.h"
#include "a2name.h"
#include "ethertyp.h"
#include "llc.h"


static void token_print (const u_char * bp, u_int length)
{
  struct token_header *tp;
  struct llc          *lp;
  u_short ether_type;

  tp = (struct token_header *) bp;
  lp = (struct llc *) (bp + TOKEN_HDR_LEN);

  if (IS_SOURCE_ROUTED(tp))
  {
    tp->ether_shost[0] = tp->ether_shost[0] & 0x7f;
    lp = (struct llc *) (bp + TOKEN_HDR_LEN + RIF_LENGTH(tp));
  }

  /* 
   * Ethertype on ethernet is a short, but ethertype in an llc-snap has
   * been defined as 2 u_chars.  This is a stupid little hack to fix
   * this for now but something better should be done using ntohs()
   * XXX
   */
  ether_type = ((u_short) lp->ethertype[1] << 16) | lp->ethertype[0];

  if (qflag)
       PRINTF ("%s %s %d: ",
               etheraddr_string (ESRC (tp)),
               etheraddr_string (EDST (tp)), length);
  else PRINTF ("%s %s %s %d: ",
               etheraddr_string (ESRC (tp)),
               etheraddr_string (EDST (tp)),
               etherproto_string (ether_type), length);
}

/*
 * This is the top level routine of the printer.  'p' is the points
 * to the ether header of the packet, 'tvp' is the timestamp,
 * 'length' is the length of the packet off the wire, and 'caplen'
 * is the number of bytes actually captured.
 */
void token_if_print (u_char *user, const struct pcap_pkthdr *h, const u_char *p)
{
  struct token_header *tp = (struct token_header *) p;
  struct llc          *lp;

  u_int   caplen = h->caplen;
  u_int   length = h->len;
  u_int   route_len = 0, seg;
  u_short ether_type;

  ts_print (&h->ts);

  if (caplen < TOKEN_HDR_LEN)
  {
    PUTS ("[|token-ring]");
    goto out;
  }

  /*
   * Some printers want to get back at the ethernet addresses,
   * and/or check that they're not walking off the end of the packet.
   * Rather than pass them all the way down, we set these globals.
   */
  tp = (struct token_header *) p;

  /* Adjust for source routing information in the MAC header
   */
  if (IS_SOURCE_ROUTED(tp))
  {
    if (eflag)
       token_print (p, length);

    route_len = RIF_LENGTH(tp);
    if (vflag)
    {
      if (vflag > 1)
         PRINTF ("ac %x fc %x ", tp->ac, tp->fc);
      ether_type = ntohs ((int) lp->ethertype);

      PRINTF ("%s ", broadcast_indicator [BROADCAST(tp)]);
      PRINTF ("%s",  direction [DIRECTION(tp)]);

      for (seg = 0; seg < SEGMENT_COUNT(tp); seg++)
         PRINTF (" [%d:%d]", RING_NUMBER(tp,seg), BRIDGE_NUMBER(tp,seg));
    }
    else
    {
      PRINTF ("rt = %x", ntohs(tp->rcf));

      for (seg = 0; seg < SEGMENT_COUNT(tp); seg++)
         PRINTF (":%x", ntohs(tp->rseg[seg]));
    }
    PRINTF (" (%s) ", largest_frame[LARGEST_FRAME(tp)]);
  }
  else
  {
    if (eflag)
      token_print (p, length);
  }

  /* Set pointer to llc header, adjusted for routing information
   */
  lp = (struct llc*) (p + TOKEN_HDR_LEN + route_len);

  packetp = p;
  snapend = p + caplen;

  /* Skip over token ring MAC header
   */
  length -= TOKEN_HDR_LEN + route_len;
  caplen -= TOKEN_HDR_LEN + route_len;
  p += TOKEN_HDR_LEN + route_len;

  extracted_ethertype = 0;

  /* Try to print the LLC-layer header & higher layers
   */
  if (llc_print (p, length, caplen, ESRC (tp), EDST (tp)) == 0)
  {
    /* ether_type not known, print raw packet
     */
    if (!eflag)
       token_print ((u_char *) tp, length);

    if (extracted_ethertype)
       PRINTF ("(LLC %s) ", etherproto_string (htons(extracted_ethertype)));

    if (!xflag && !qflag)
       default_print (p, caplen);
  }

  if (xflag)
    default_print (p, caplen);

out:
  PUTCHAR ('\n');
}