/*

* 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.

*/

#define NETDISSECT_REWORKED

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <tcpdump-stdinc.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(netdissect_options *, const u_char *, const u_char *, u_int);

static int print_report(netdissect_options *, const u_char *, const u_char *, u_int);

static int print_neighbors(netdissect_options *, const u_char *, const u_char *, u_int);

static int print_neighbors2(netdissect_options *, const u_char *, const u_char *, u_int);

static int print_prune(netdissect_options *, const u_char *);

static int print_graft(netdissect_options *, const u_char *);

static int print_graft_ack(netdissect_options *, const u_char *);

static u_int32_t target_level;

void

dvmrp_print(netdissect_options *ndo,

register const u_char *bp, register u_int len)

{

register const u_char *ep;

register u_char type;

ep = (const u_char *)ndo->ndo_snapend;

if (bp >= ep)

return;

ND_TCHECK(bp[1]);

type = bp[1];

/* Skip IGMP header */

bp += 8;

len -= 8;

switch (type) {

case DVMRP_PROBE:

ND_PRINT((ndo, " Probe"));

if (ndo->ndo_vflag) {

if (print_probe(ndo, bp, ep, len) < 0)

goto trunc;

}

break;

case DVMRP_REPORT:

ND_PRINT((ndo, " Report"));

if (ndo->ndo_vflag > 1) {

if (print_report(ndo, bp, ep, len) < 0)

goto trunc;

}

break;

case DVMRP_ASK_NEIGHBORS:

ND_PRINT((ndo, " Ask-neighbors(old)"));

break;

case DVMRP_NEIGHBORS:

ND_PRINT((ndo, " Neighbors(old)"));

if (print_neighbors(ndo, bp, ep, len) < 0)

goto trunc;

break;

case DVMRP_ASK_NEIGHBORS2:

ND_PRINT((ndo, " Ask-neighbors2"));

break;

case DVMRP_NEIGHBORS2:

ND_PRINT((ndo, " Neighbors2"));

/*

* extract version and capabilities from IGMP group

* address field

*/

bp -= 4;

ND_TCHECK2(bp[0], 4);

target_level = (bp[0] << 24) | (bp[1] << 16) |

(bp[2] << 8) | bp[3];

bp += 4;

if (print_neighbors2(ndo, bp, ep, len) < 0)

goto trunc;

break;

case DVMRP_PRUNE:

ND_PRINT((ndo, " Prune"));

if (print_prune(ndo, bp) < 0)

goto trunc;

break;

case DVMRP_GRAFT:

ND_PRINT((ndo, " Graft"));

if (print_graft(ndo, bp) < 0)

goto trunc;

break;

case DVMRP_GRAFT_ACK:

ND_PRINT((ndo, " Graft-ACK"));

if (print_graft_ack(ndo, bp) < 0)

goto trunc;

break;

default:

ND_PRINT((ndo, " [type %d]", type));

break;

}

return;

trunc:

ND_PRINT((ndo, "[|dvmrp]"));

return;

}

static int

print_report(netdissect_options *ndo,

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) {

ND_PRINT((ndo, " [|]"));

return (0);

}

ND_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;

ND_PRINT((ndo, "\n\tMask %s", intoa(htonl(mask))));

bp += 3;

len -= 3;

do {

if (bp + width + 1 > ep) {

ND_PRINT((ndo, " [|]"));

return (0);

}

if (len < width + 1) {

ND_PRINT((ndo, "\n\t [Truncated Report]"));

return (0);

}

origin = 0;

for (i = 0; i < width; ++i) {

ND_TCHECK(*bp);

origin = origin << 8 | *bp++;

}

for ( ; i < 4; ++i)

origin <<= 8;

ND_TCHECK(*bp);

metric = *bp++;

done = metric & 0x80;

metric &= 0x7f;

ND_PRINT((ndo, "\n\t %s metric %d", intoa(htonl(origin)),

metric));

len -= width + 1;

} while (!done);

}

return (0);

trunc:

return (-1);

}

static int

print_probe(netdissect_options *ndo,

register const u_char *bp, register const u_char *ep,

register u_int len)

{

register u_int32_t genid;

ND_TCHECK2(bp[0], 4);

if ((len < 4) || ((bp + 4) > ep)) {

/* { (ctags) */

ND_PRINT((ndo, " [|}"));

return (0);

}

genid = (bp[0] << 24) | (bp[1] << 16) | (bp[2] << 8) | bp[3];

bp += 4;

len -= 4;

ND_PRINT((ndo, ndo->ndo_vflag > 1 ? "\n\t" : " "));

ND_PRINT((ndo, "genid %u", genid));

if (ndo->ndo_vflag < 2)

return (0);

while ((len > 0) && (bp < ep)) {

ND_TCHECK2(bp[0], 4);

ND_PRINT((ndo, "\n\tneighbor %s", ipaddr_string(ndo, bp)));

bp += 4; len -= 4;

}

return (0);

trunc:

return (-1);

}

static int

print_neighbors(netdissect_options *ndo,

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) {

ND_TCHECK2(bp[0], 7);

laddr = bp;

bp += 4;

metric = *bp++;

thresh = *bp++;

ncount = *bp++;

len -= 7;

while (--ncount >= 0) {

ND_TCHECK2(bp[0], 4);

ND_PRINT((ndo, " [%s ->", ipaddr_string(ndo, laddr)));

ND_PRINT((ndo, " %s, (%d/%d)]",

ipaddr_string(ndo, bp), metric, thresh));

bp += 4;

len -= 4;

}

}

return (0);

trunc:

return (-1);

}

static int

print_neighbors2(netdissect_options *ndo,

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;

ND_PRINT((ndo, " (v %d.%d):",

(int)target_level & 0xff,

(int)(target_level >> 8) & 0xff));

while (len > 0 && bp < ep) {

ND_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) {

ND_PRINT((ndo, " [%s -> ", ipaddr_string(ndo, laddr)));

ND_PRINT((ndo, "%s (%d/%d", ipaddr_string(ndo, bp),

metric, thresh));

if (flags & DVMRP_NF_TUNNEL)

ND_PRINT((ndo, "/tunnel"));

if (flags & DVMRP_NF_SRCRT)

ND_PRINT((ndo, "/srcrt"));

if (flags & DVMRP_NF_QUERIER)

ND_PRINT((ndo, "/querier"));

if (flags & DVMRP_NF_DISABLED)

ND_PRINT((ndo, "/disabled"));

if (flags & DVMRP_NF_DOWN)

ND_PRINT((ndo, "/down"));

ND_PRINT((ndo, ")]"));

bp += 4;

len -= 4;

}

if (ncount != -1) {

ND_PRINT((ndo, " [|]"));

return (0);

}

}

return (0);

trunc:

return (-1);

}

static int

print_prune(netdissect_options *ndo,

register const u_char *bp)

{

ND_TCHECK2(bp[0], 12);

ND_PRINT((ndo, " src %s grp %s", ipaddr_string(ndo, bp), ipaddr_string(ndo, bp + 4)));

bp += 8;

ND_PRINT((ndo, " timer "));

relts_print(ndo, EXTRACT_32BITS(bp));

return (0);

trunc:

return (-1);

}

static int

print_graft(netdissect_options *ndo,

register const u_char *bp)

{

ND_TCHECK2(bp[0], 8);

ND_PRINT((ndo, " src %s grp %s", ipaddr_string(ndo, bp), ipaddr_string(ndo, bp + 4)));

return (0);

trunc:

return (-1);

}

static int

print_graft_ack(netdissect_options *ndo,

register const u_char *bp)

{

ND_TCHECK2(bp[0], 8);

ND_PRINT((ndo, " src %s grp %s", ipaddr_string(ndo, bp), ipaddr_string(ndo, bp + 4)));

return (0);

trunc:

return (-1);

}