tcpdump/print-hsrp.c
2018-02-12 13:53:37 +01:00

139 lines
4.6 KiB
C

/*
* Copyright (C) 2001 Julian Cowley
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project 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 BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/* \summary: Cisco Hot Standby Router Protocol (HSRP) printer */
/* specification: RFC 2281 for version 1 */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "addrtoname.h"
#include "extract.h"
/* HSRP op code types. */
static const char *op_code_str[] = {
"hello",
"coup",
"resign"
};
/* HSRP states and associated names. */
static const struct tok states[] = {
{ 0, "initial" },
{ 1, "learn" },
{ 2, "listen" },
{ 4, "speak" },
{ 8, "standby" },
{ 16, "active" },
{ 0, NULL }
};
/*
* RFC 2281:
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Version | Op Code | State | Hellotime |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Holdtime | Priority | Group | Reserved |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Virtual IP Address |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
#define HSRP_AUTH_SIZE 8
/* HSRP protocol header. */
struct hsrp {
nd_uint8_t hsrp_version;
nd_uint8_t hsrp_op_code;
nd_uint8_t hsrp_state;
nd_uint8_t hsrp_hellotime;
nd_uint8_t hsrp_holdtime;
nd_uint8_t hsrp_priority;
nd_uint8_t hsrp_group;
nd_uint8_t hsrp_reserved;
nd_byte hsrp_authdata[HSRP_AUTH_SIZE];
nd_ipv4 hsrp_virtaddr;
};
void
hsrp_print(netdissect_options *ndo, const u_char *bp, u_int len)
{
const struct hsrp *hp = (const struct hsrp *) bp;
uint8_t version;
ND_TCHECK_1(hp->hsrp_version);
version = EXTRACT_U_1(hp->hsrp_version);
ND_PRINT("HSRPv%u", version);
if (version != 0)
return;
ND_TCHECK_1(hp->hsrp_op_code);
ND_PRINT("-");
ND_PRINT("%s ", tok2strary(op_code_str, "unknown (%u)", EXTRACT_U_1(hp->hsrp_op_code)));
ND_PRINT("%u: ", len);
ND_TCHECK_1(hp->hsrp_state);
ND_PRINT("state=%s ", tok2str(states, "Unknown (%u)", EXTRACT_U_1(hp->hsrp_state)));
ND_TCHECK_1(hp->hsrp_group);
ND_PRINT("group=%u ", EXTRACT_U_1(hp->hsrp_group));
ND_TCHECK_1(hp->hsrp_reserved);
if (EXTRACT_U_1(hp->hsrp_reserved) != 0) {
ND_PRINT("[reserved=%u!] ", EXTRACT_U_1(hp->hsrp_reserved));
}
ND_TCHECK_4(hp->hsrp_virtaddr);
ND_PRINT("addr=%s", ipaddr_string(ndo, hp->hsrp_virtaddr));
if (ndo->ndo_vflag) {
ND_PRINT(" hellotime=");
unsigned_relts_print(ndo, EXTRACT_U_1(hp->hsrp_hellotime));
ND_PRINT(" holdtime=");
unsigned_relts_print(ndo, EXTRACT_U_1(hp->hsrp_holdtime));
ND_PRINT(" priority=%u", EXTRACT_U_1(hp->hsrp_priority));
ND_PRINT(" auth=\"");
if (fn_printn(ndo, hp->hsrp_authdata, sizeof(hp->hsrp_authdata),
ndo->ndo_snapend)) {
ND_PRINT("\"");
goto trunc;
}
ND_PRINT("\"");
}
return;
trunc:
ND_PRINT("[|hsrp]");
}