tcpdump/print-dvmrp.c
Guy Harris fb2479d733 Always include <config.h> rather than "config.h".
This can prevent bizarre failures if, for example, you've done a
configuration in the top-level source directory, leaving behind one
config.h file, and then do an out-of-tree build in another directory,
with different configuration options.  This way, we always pick up the
same config.h, in the build directory.
2018-01-21 12:27:28 -08:00

379 lines
8.8 KiB
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.
*/
/* \summary: Distance Vector Multicast Routing Protocol printer */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "extract.h"
#include "addrtoname.h"
/*
* See: RFC 1075 and draft-ietf-idmr-dvmrp-v3
*
* 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, uint8_t, uint8_t);
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 *);
void
dvmrp_print(netdissect_options *ndo,
const u_char *bp, u_int len)
{
const u_char *ep;
u_char type;
uint8_t major_version, minor_version;
ep = ndo->ndo_snapend;
if (bp >= ep)
return;
ND_TCHECK_1(bp + 1);
type = EXTRACT_U_1(bp + 1);
/* Skip IGMP header */
bp += 8;
len -= 8;
switch (type) {
case DVMRP_PROBE:
ND_PRINT(" Probe");
if (ndo->ndo_vflag) {
if (print_probe(ndo, bp, ep, len) < 0)
goto trunc;
}
break;
case DVMRP_REPORT:
ND_PRINT(" Report");
if (ndo->ndo_vflag > 1) {
if (print_report(ndo, bp, ep, len) < 0)
goto trunc;
}
break;
case DVMRP_ASK_NEIGHBORS:
ND_PRINT(" Ask-neighbors(old)");
break;
case DVMRP_NEIGHBORS:
ND_PRINT(" Neighbors(old)");
if (print_neighbors(ndo, bp, ep, len) < 0)
goto trunc;
break;
case DVMRP_ASK_NEIGHBORS2:
ND_PRINT(" Ask-neighbors2");
break;
case DVMRP_NEIGHBORS2:
ND_PRINT(" Neighbors2");
/*
* extract version from IGMP group address field
*/
bp -= 4;
ND_TCHECK_4(bp);
major_version = EXTRACT_U_1(bp + 3);
minor_version = EXTRACT_U_1(bp + 2);
bp += 4;
if (print_neighbors2(ndo, bp, ep, len, major_version,
minor_version) < 0)
goto trunc;
break;
case DVMRP_PRUNE:
ND_PRINT(" Prune");
if (print_prune(ndo, bp) < 0)
goto trunc;
break;
case DVMRP_GRAFT:
ND_PRINT(" Graft");
if (print_graft(ndo, bp) < 0)
goto trunc;
break;
case DVMRP_GRAFT_ACK:
ND_PRINT(" Graft-ACK");
if (print_graft_ack(ndo, bp) < 0)
goto trunc;
break;
default:
ND_PRINT(" [type %u]", type);
break;
}
return;
trunc:
ND_PRINT("[|dvmrp]");
return;
}
static int
print_report(netdissect_options *ndo,
const u_char *bp, const u_char *ep,
u_int len)
{
uint32_t mask, origin;
u_int metric, done;
u_int i, width;
while (len > 0) {
if (len < 3) {
ND_PRINT(" [|]");
return (0);
}
ND_TCHECK_3(bp);
mask = (uint32_t)0xff << 24 | EXTRACT_U_1(bp) << 16 |
EXTRACT_U_1(bp + 1) << 8 | EXTRACT_U_1(bp + 2);
width = 1;
if (EXTRACT_U_1(bp))
width = 2;
if (EXTRACT_U_1(bp + 1))
width = 3;
if (EXTRACT_U_1(bp + 2))
width = 4;
ND_PRINT("\n\tMask %s", intoa(htonl(mask)));
bp += 3;
len -= 3;
do {
if (bp + width + 1 > ep) {
ND_PRINT(" [|]");
return (0);
}
if (len < width + 1) {
ND_PRINT("\n\t [Truncated Report]");
return (0);
}
origin = 0;
for (i = 0; i < width; ++i) {
ND_TCHECK_1(bp);
origin = origin << 8 | EXTRACT_U_1(bp);
bp++;
}
for ( ; i < 4; ++i)
origin <<= 8;
ND_TCHECK_1(bp);
metric = EXTRACT_U_1(bp);
bp++;
done = metric & 0x80;
metric &= 0x7f;
ND_PRINT("\n\t %s metric %u", intoa(htonl(origin)),
metric);
len -= width + 1;
} while (!done);
}
return (0);
trunc:
return (-1);
}
static int
print_probe(netdissect_options *ndo,
const u_char *bp, const u_char *ep,
u_int len)
{
uint32_t genid;
ND_TCHECK_4(bp);
if ((len < 4) || ((bp + 4) > ep)) {
/* { (ctags) */
ND_PRINT(" [|}");
return (0);
}
genid = (EXTRACT_U_1(bp) << 24) | (EXTRACT_U_1(bp + 1) << 16) |
(EXTRACT_U_1(bp + 2) << 8) | EXTRACT_U_1(bp + 3);
bp += 4;
len -= 4;
ND_PRINT(ndo->ndo_vflag > 1 ? "\n\t" : " ");
ND_PRINT("genid %u", genid);
if (ndo->ndo_vflag < 2)
return (0);
while ((len > 0) && (bp < ep)) {
ND_TCHECK_4(bp);
ND_PRINT("\n\tneighbor %s", ipaddr_string(ndo, bp));
bp += 4; len -= 4;
}
return (0);
trunc:
return (-1);
}
static int
print_neighbors(netdissect_options *ndo,
const u_char *bp, const u_char *ep,
u_int len)
{
const u_char *laddr;
u_char metric;
u_char thresh;
int ncount;
while (len > 0 && bp < ep) {
ND_TCHECK_7(bp);
laddr = bp;
bp += 4;
metric = EXTRACT_U_1(bp);
bp++;
thresh = EXTRACT_U_1(bp);
bp++;
ncount = EXTRACT_U_1(bp);
bp++;
len -= 7;
while (--ncount >= 0) {
ND_TCHECK_4(bp);
ND_PRINT(" [%s ->", ipaddr_string(ndo, laddr));
ND_PRINT(" %s, (%u/%u)]",
ipaddr_string(ndo, bp), metric, thresh);
bp += 4;
len -= 4;
}
}
return (0);
trunc:
return (-1);
}
static int
print_neighbors2(netdissect_options *ndo,
const u_char *bp, const u_char *ep,
u_int len, uint8_t major_version,
uint8_t minor_version)
{
const u_char *laddr;
u_char metric, thresh, flags;
int ncount;
ND_PRINT(" (v %u.%u):", major_version, minor_version);
while (len > 0 && bp < ep) {
ND_TCHECK_8(bp);
laddr = bp;
bp += 4;
metric = EXTRACT_U_1(bp);
bp++;
thresh = EXTRACT_U_1(bp);
bp++;
flags = EXTRACT_U_1(bp);
bp++;
ncount = EXTRACT_U_1(bp);
bp++;
len -= 8;
while (--ncount >= 0 && (len >= 4) && (bp + 4) <= ep) {
ND_PRINT(" [%s -> ", ipaddr_string(ndo, laddr));
ND_PRINT("%s (%u/%u", ipaddr_string(ndo, bp),
metric, thresh);
if (flags & DVMRP_NF_TUNNEL)
ND_PRINT("/tunnel");
if (flags & DVMRP_NF_SRCRT)
ND_PRINT("/srcrt");
if (flags & DVMRP_NF_QUERIER)
ND_PRINT("/querier");
if (flags & DVMRP_NF_DISABLED)
ND_PRINT("/disabled");
if (flags & DVMRP_NF_DOWN)
ND_PRINT("/down");
ND_PRINT(")]");
bp += 4;
len -= 4;
}
if (ncount != -1) {
ND_PRINT(" [|]");
return (0);
}
}
return (0);
trunc:
return (-1);
}
static int
print_prune(netdissect_options *ndo,
const u_char *bp)
{
ND_TCHECK_LEN(bp, 12);
ND_PRINT(" src %s grp %s", ipaddr_string(ndo, bp), ipaddr_string(ndo, bp + 4));
bp += 8;
ND_PRINT(" timer ");
unsigned_relts_print(ndo, EXTRACT_BE_U_4(bp));
return (0);
trunc:
return (-1);
}
static int
print_graft(netdissect_options *ndo,
const u_char *bp)
{
ND_TCHECK_8(bp);
ND_PRINT(" 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,
const u_char *bp)
{
ND_TCHECK_8(bp);
ND_PRINT(" src %s grp %s", ipaddr_string(ndo, bp), ipaddr_string(ndo, bp + 4));
return (0);
trunc:
return (-1);
}