tcpdump/print-rt6.c
Guy Harris 93493458ca ip6r0_reserved is an array of octets; extract the value from it.
dp0->ip6r0_reserved evaluates to a pointer to the first element of the
array, which is always non-null, so it doesn't test whether the *value*
of the field is non-zero.  Call EXTRACT_32BITS() on it to check whether
the value is zero.
2017-09-13 12:25:44 +01:00

94 lines
2.7 KiB
C

/*
* Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994
* 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: IPv6 routing header printer */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <netdissect-stdinc.h>
#include <string.h>
#include "netdissect.h"
#include "addrtoname.h"
#include "extract.h"
#include "ip6.h"
int
rt6_print(netdissect_options *ndo, register const u_char *bp, const u_char *bp2 _U_)
{
register const struct ip6_rthdr *dp;
register const struct ip6_rthdr0 *dp0;
register const u_char *ep;
int i, len;
register const struct in6_addr *addr;
dp = (const struct ip6_rthdr *)bp;
/* 'ep' points to the end of available data. */
ep = ndo->ndo_snapend;
ND_TCHECK(dp->ip6r_segleft);
len = dp->ip6r_len;
ND_PRINT((ndo, "srcrt (len=%d", dp->ip6r_len)); /*)*/
ND_PRINT((ndo, ", type=%d", dp->ip6r_type));
ND_PRINT((ndo, ", segleft=%d", dp->ip6r_segleft));
switch (dp->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
case IPV6_RTHDR_TYPE_2: /* Mobile IPv6 ID-20 */
dp0 = (const struct ip6_rthdr0 *)dp;
ND_TCHECK(dp0->ip6r0_reserved);
if (EXTRACT_32BITS(dp0->ip6r0_reserved) || ndo->ndo_vflag) {
ND_PRINT((ndo, ", rsv=0x%0x",
EXTRACT_32BITS(&dp0->ip6r0_reserved)));
}
if (len % 2 == 1)
goto trunc;
len >>= 1;
addr = &dp0->ip6r0_addr[0];
for (i = 0; i < len; i++) {
if ((const u_char *)(addr + 1) > ep)
goto trunc;
ND_PRINT((ndo, ", [%d]%s", i, ip6addr_string(ndo, addr)));
addr++;
}
/*(*/
ND_PRINT((ndo, ") "));
return((dp0->ip6r0_len + 1) << 3);
break;
default:
goto trunc;
break;
}
trunc:
ND_PRINT((ndo, "[|srcrt]"));
return -1;
}