/*      $OpenBSD: print-hsrp.c,v 1.5 2015/11/16 00:16:39 mmcc Exp $     */

/*
 * 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.
 */

/* Cisco Hot Standby Router Protocol (HSRP). */

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

#include <sys/types.h>

#include <stdio.h>
#include <netinet/in.h>

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

/* HSRP op code types. */
static const char *op_code_str[] = {
        "hello",
        "coup",
        "resign"
};

/* HSRP states and associated names. */
static 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 {
        u_char          hsrp_version;
        u_char          hsrp_op_code;
        u_char          hsrp_state;
        u_char          hsrp_hellotime;
        u_char          hsrp_holdtime;
        u_char          hsrp_priority;
        u_char          hsrp_group;
        u_char          hsrp_reserved;
        u_char          hsrp_authdata[HSRP_AUTH_SIZE];
        struct in_addr  hsrp_virtaddr;
};

void
hsrp_print(const u_char *bp, u_int len)
{
        struct hsrp *hp = (struct hsrp *) bp;

        TCHECK(hp->hsrp_version);
        printf("HSRPv%d", hp->hsrp_version);
        if (hp->hsrp_version != 0)
                return;
        TCHECK(hp->hsrp_op_code);
        printf("-");
        if (hp->hsrp_op_code >= sizeof(op_code_str)/sizeof(*op_code_str))
                printf("unknown (%d) ", hp->hsrp_op_code);
        else
                printf("%s ", op_code_str[hp->hsrp_op_code]);
        printf("%d: ", len);
        TCHECK(hp->hsrp_state);
        printf("state=%s ", tok2str(states, "Unknown (%d)", hp->hsrp_state));
        TCHECK(hp->hsrp_group);
        printf("group=%d ", hp->hsrp_group);
        TCHECK(hp->hsrp_reserved);
        if (hp->hsrp_reserved != 0) {
                printf("[reserved=%d!] ", hp->hsrp_reserved);
        }
        TCHECK2(hp->hsrp_virtaddr, sizeof(hp->hsrp_virtaddr));
        printf("addr=%s", ipaddr_string(&hp->hsrp_virtaddr));
        if (vflag) {
                printf(" hellotime=");
                relts_print(hp->hsrp_hellotime);
                printf(" holdtime=");
                relts_print(hp->hsrp_holdtime);
                printf(" priority=%d", hp->hsrp_priority);
                printf(" auth=\"");
                fn_printn(hp->hsrp_authdata, sizeof(hp->hsrp_authdata), NULL);
                printf("\"");
        }
        return;
trunc:
        printf("[|hsrp]");
}