Logo Search packages:      
Sourcecode: tcpdump version File versions

print-dvmrp.c

/*
 * Copyright (c) 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.
 */

#ifndef lint
static const char rcsid[] _U_ =
    "@(#) $Header: /tcpdump/master/tcpdump/print-dvmrp.c,v 1.24.2.3 2003/11/19 09:41:28 guy Exp $ (LBL)";
#endif

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

#include <tcpdump-stdinc.h>

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

#include "interface.h"
#include "extract.h"
#include "addrtoname.h"

/*
 * DVMRP message types and flag values shamelessly stolen from
 * mrouted/dvmrp.h.
 */
#define DVMRP_PROBE           1     /* for finding neighbors */
#define DVMRP_REPORT          2     /* for reporting some or all routes */
#define DVMRP_ASK_NEIGHBORS   3     /* sent by mapper, asking for a list */
                              /* of this router's neighbors */
#define DVMRP_NEIGHBORS       4     /* response to such a request */
#define DVMRP_ASK_NEIGHBORS2  5     /* as above, want new format reply */
#define DVMRP_NEIGHBORS2      6
#define DVMRP_PRUNE           7     /* prune message */
#define DVMRP_GRAFT           8     /* graft message */
#define DVMRP_GRAFT_ACK       9     /* graft acknowledgement */

/*
 * 'flags' byte values in DVMRP_NEIGHBORS2 reply.
 */
#define DVMRP_NF_TUNNEL       0x01  /* neighbors reached via tunnel */
#define DVMRP_NF_SRCRT        0x02  /* tunnel uses IP source routing */
#define DVMRP_NF_DOWN         0x10  /* kernel state of interface */
#define DVMRP_NF_DISABLED     0x20  /* administratively disabled */
#define DVMRP_NF_QUERIER      0x40  /* I am the subnet's querier */

static int print_probe(const u_char *, const u_char *, u_int);
static int print_report(const u_char *, const u_char *, u_int);
static int print_neighbors(const u_char *, const u_char *, u_int);
static int print_neighbors2(const u_char *, const u_char *, u_int);
static int print_prune(const u_char *);
static int print_graft(const u_char *);
static int print_graft_ack(const u_char *);

static u_int32_t target_level;

void
dvmrp_print(register const u_char *bp, register u_int len)
{
      register const u_char *ep;
      register u_char type;

      ep = (const u_char *)snapend;
      if (bp >= ep)
            return;

      TCHECK(bp[1]);
      type = bp[1];

      /* Skip IGMP header */
      bp += 8;
      len -= 8;

      switch (type) {

      case DVMRP_PROBE:
            printf(" Probe");
            if (vflag) {
                  if (print_probe(bp, ep, len) < 0)
                        goto trunc;
            }
            break;

      case DVMRP_REPORT:
            printf(" Report");
            if (vflag > 1) {
                  if (print_report(bp, ep, len) < 0)
                        goto trunc;
            }
            break;

      case DVMRP_ASK_NEIGHBORS:
            printf(" Ask-neighbors(old)");
            break;

      case DVMRP_NEIGHBORS:
            printf(" Neighbors(old)");
            if (print_neighbors(bp, ep, len) < 0)
                  goto trunc;
            break;

      case DVMRP_ASK_NEIGHBORS2:
            printf(" Ask-neighbors2");
            break;

      case DVMRP_NEIGHBORS2:
            printf(" Neighbors2");
            /*
             * extract version and capabilities from IGMP group
             * address field
             */
            bp -= 4;
            TCHECK2(bp[0], 4);
            target_level = (bp[0] << 24) | (bp[1] << 16) |
                (bp[2] << 8) | bp[3];
            bp += 4;
            if (print_neighbors2(bp, ep, len) < 0)
                  goto trunc;
            break;

      case DVMRP_PRUNE:
            printf(" Prune");
            if (print_prune(bp) < 0)
                  goto trunc;
            break;

      case DVMRP_GRAFT:
            printf(" Graft");
            if (print_graft(bp) < 0)
                  goto trunc;
            break;

      case DVMRP_GRAFT_ACK:
            printf(" Graft-ACK");
            if (print_graft_ack(bp) < 0)
                  goto trunc;
            break;

      default:
            printf(" [type %d]", type);
            break;
      }
      return;

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

static int 
print_report(register const u_char *bp, register const u_char *ep,
    register u_int len)
{
      register u_int32_t mask, origin;
      register int metric, done;
      register u_int i, width;

      while (len > 0) {
            if (len < 3) {
                  printf(" [|]");
                  return (0);
            }
            TCHECK2(bp[0], 3);
            mask = (u_int32_t)0xff << 24 | bp[0] << 16 | bp[1] << 8 | bp[2];
            width = 1;
            if (bp[0])
                  width = 2;
            if (bp[1])
                  width = 3;
            if (bp[2])
                  width = 4;

            printf("\n\tMask %s", intoa(htonl(mask)));
            bp += 3;
            len -= 3;
            do {
                  if (bp + width + 1 > ep) {
                        printf(" [|]");
                        return (0);
                  }
                  if (len < width + 1) {
                        printf("\n\t  [Truncated Report]");
                        return (0);
                  }
                  origin = 0;
                  for (i = 0; i < width; ++i) {
                        TCHECK(*bp);
                        origin = origin << 8 | *bp++;
                  }
                  for ( ; i < 4; ++i)
                        origin <<= 8;

                  TCHECK(*bp);
                  metric = *bp++;
                  done = metric & 0x80;
                  metric &= 0x7f;
                  printf("\n\t  %s metric %d", intoa(htonl(origin)),
                        metric);
                  len -= width + 1;
            } while (!done);
      }
      return (0);
trunc:
      return (-1);
}

static int
print_probe(register const u_char *bp, register const u_char *ep,
    register u_int len)
{
      register u_int32_t genid;

      TCHECK2(bp[0], 4);
      if ((len < 4) || ((bp + 4) > ep)) {
            /* { (ctags) */
            printf(" [|}");
            return (0);
      }
      genid = (bp[0] << 24) | (bp[1] << 16) | (bp[2] << 8) | bp[3];
      bp += 4;
      len -= 4;
      if (vflag > 1)
            printf("\n\t");
      else
            printf(" ");
      printf("genid %u", genid);
      if (vflag < 2)
            return (0);

      while ((len > 0) && (bp < ep)) {
            TCHECK2(bp[0], 4);
            printf("\n\tneighbor %s", ipaddr_string(bp));
            bp += 4; len -= 4;
      }
      return (0);
trunc:
      return (-1);
}

static int
print_neighbors(register const u_char *bp, register const u_char *ep,
    register u_int len)
{
      const u_char *laddr;
      register u_char metric;
      register u_char thresh;
      register int ncount;

      while (len > 0 && bp < ep) {
            TCHECK2(bp[0], 7);
            laddr = bp;
            bp += 4;
            metric = *bp++;
            thresh = *bp++;
            ncount = *bp++;
            len -= 7;
            while (--ncount >= 0) {
                  TCHECK2(bp[0], 4);
                  printf(" [%s ->", ipaddr_string(laddr));
                  printf(" %s, (%d/%d)]",
                           ipaddr_string(bp), metric, thresh);
                  bp += 4;
                  len -= 4;
            }
      }
      return (0);
trunc:
      return (-1);
}

static int
print_neighbors2(register const u_char *bp, register const u_char *ep,
    register u_int len)
{
      const u_char *laddr;
      register u_char metric, thresh, flags;
      register int ncount;

      printf(" (v %d.%d):",
             (int)target_level & 0xff,
             (int)(target_level >> 8) & 0xff);

      while (len > 0 && bp < ep) {
            TCHECK2(bp[0], 8);
            laddr = bp;
            bp += 4;
            metric = *bp++;
            thresh = *bp++;
            flags = *bp++;
            ncount = *bp++;
            len -= 8;
            while (--ncount >= 0 && (len >= 4) && (bp + 4) <= ep) {
                  printf(" [%s -> ", ipaddr_string(laddr));
                  printf("%s (%d/%d", ipaddr_string(bp),
                             metric, thresh);
                  if (flags & DVMRP_NF_TUNNEL)
                        printf("/tunnel");
                  if (flags & DVMRP_NF_SRCRT)
                        printf("/srcrt");
                  if (flags & DVMRP_NF_QUERIER)
                        printf("/querier");
                  if (flags & DVMRP_NF_DISABLED)
                        printf("/disabled");
                  if (flags & DVMRP_NF_DOWN)
                        printf("/down");
                  printf(")]");
                  bp += 4;
                  len -= 4;
            }
            if (ncount != -1) {
                  printf(" [|]");
                  return (0);
            }
      }
      return (0);
trunc:
      return (-1);
}

static int
print_prune(register const u_char *bp)
{
      TCHECK2(bp[0], 12);
      printf(" src %s grp %s", ipaddr_string(bp), ipaddr_string(bp + 4));
      bp += 8;
      (void)printf(" timer ");
      relts_print(EXTRACT_32BITS(bp));
      return (0);
trunc:
      return (-1);
}

static int
print_graft(register const u_char *bp)
{
      TCHECK2(bp[0], 8);
      printf(" src %s grp %s", ipaddr_string(bp), ipaddr_string(bp + 4));
      return (0);
trunc:
      return (-1);
}

static int
print_graft_ack(register const u_char *bp)
{
      TCHECK2(bp[0], 8);
      printf(" src %s grp %s", ipaddr_string(bp), ipaddr_string(bp + 4));
      return (0);
trunc:
      return (-1);
}

Generated by  Doxygen 1.6.0   Back to index