The Tcpdump Group git mirrors - tcpdump/blob - print-hsrp.c

   1 /*
   2  * Copyright (C) 2001 Julian Cowley
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the project nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 /* Cisco Hot Standby Router Protocol (HSRP). */
  31
  32 #define NETDISSECT_REWORKED
  33 #ifdef HAVE_CONFIG_H
  34 #include "config.h"
  35 #endif
  36
  37 #include <tcpdump-stdinc.h>
  38
  39 #include "interface.h"
  40 #include "addrtoname.h"
  41
  42 /* HSRP op code types. */
  43 static const char *op_code_str[] = {
  44         "hello",
  45         "coup",
  46         "resign"
  47 };
  48
  49 /* HSRP states and associated names. */
  50 static const struct tok states[] = {
  51         {  0, "initial" },
  52         {  1, "learn" },
  53         {  2, "listen" },
  54         {  4, "speak" },
  55         {  8, "standby" },
  56         { 16, "active" },
  57         {  0, NULL }
  58 };
  59
  60 /*
  61  * RFC 2281:
  62  *
  63  *  0                   1                   2                   3
  64  *  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
  65  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  66  * |   Version     |   Op Code     |     State     |   Hellotime   |
  67  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  68  * |   Holdtime    |   Priority    |     Group     |   Reserved    |
  69  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  70  * |                      Authentication  Data                     |
  71  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  72  * |                      Authentication  Data                     |
  73  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  74  * |                      Virtual IP Address                       |
  75  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  76  */
  77
  78 #define HSRP_AUTH_SIZE  8
  79
  80 /* HSRP protocol header. */
  81 struct hsrp {
  82         uint8_t         hsrp_version;
  83         uint8_t         hsrp_op_code;
  84         uint8_t         hsrp_state;
  85         uint8_t         hsrp_hellotime;
  86         uint8_t         hsrp_holdtime;
  87         uint8_t         hsrp_priority;
  88         uint8_t         hsrp_group;
  89         uint8_t         hsrp_reserved;
  90         uint8_t         hsrp_authdata[HSRP_AUTH_SIZE];
  91         struct in_addr  hsrp_virtaddr;
  92 };
  93
  94 void
  95 hsrp_print(netdissect_options *ndo, register const uint8_t *bp, register u_int len)
  96 {
  97         struct hsrp *hp = (struct hsrp *) bp;
  98
  99         ND_TCHECK(hp->hsrp_version);
 100         ND_PRINT((ndo, "HSRPv%d", hp->hsrp_version));
 101         if (hp->hsrp_version != 0)
 102                 return;
 103         ND_TCHECK(hp->hsrp_op_code);
 104         ND_PRINT((ndo, "-"));
 105         ND_PRINT((ndo, "%s ", tok2strary(op_code_str, "unknown (%d)", hp->hsrp_op_code)));
 106         ND_PRINT((ndo, "%d: ", len));
 107         ND_TCHECK(hp->hsrp_state);
 108         ND_PRINT((ndo, "state=%s ", tok2str(states, "Unknown (%d)", hp->hsrp_state)));
 109         ND_TCHECK(hp->hsrp_group);
 110         ND_PRINT((ndo, "group=%d ", hp->hsrp_group));
 111         ND_TCHECK(hp->hsrp_reserved);
 112         if (hp->hsrp_reserved != 0) {
 113                 ND_PRINT((ndo, "[reserved=%d!] ", hp->hsrp_reserved));
 114         }
 115         ND_TCHECK(hp->hsrp_virtaddr);
 116         ND_PRINT((ndo, "addr=%s", ipaddr_string(ndo, &hp->hsrp_virtaddr)));
 117         if (ndo->ndo_vflag) {
 118                 ND_PRINT((ndo, " hellotime="));
 119                 relts_print(ndo, hp->hsrp_hellotime);
 120                 ND_PRINT((ndo, " holdtime="));
 121                 relts_print(ndo, hp->hsrp_holdtime);
 122                 ND_PRINT((ndo, " priority=%d", hp->hsrp_priority));
 123                 ND_PRINT((ndo, " auth=\""));
 124                 if (fn_printn(ndo, hp->hsrp_authdata, sizeof(hp->hsrp_authdata),
 125                     ndo->ndo_snapend)) {
 126                         ND_PRINT((ndo, "\""));
 127                         goto trunc;
 128                 }
 129                 ND_PRINT((ndo, "\""));
 130         }
 131         return;
 132 trunc:
 133         ND_PRINT((ndo, "[|hsrp]"));
 134 }