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 /* \summary: Cisco Hot Standby Router Protocol (HSRP) printer */ 31 32 /* specification: RFC 2281 for version 1 */ 33 34 #include <config.h> 35 36 #include "netdissect-stdinc.h" 37 38 #include "netdissect.h" 39 #include "addrtoname.h" 40 #include "extract.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 nd_uint8_t hsrp_version; 83 nd_uint8_t hsrp_op_code; 84 nd_uint8_t hsrp_state; 85 nd_uint8_t hsrp_hellotime; 86 nd_uint8_t hsrp_holdtime; 87 nd_uint8_t hsrp_priority; 88 nd_uint8_t hsrp_group; 89 nd_uint8_t hsrp_reserved; 90 nd_byte hsrp_authdata[HSRP_AUTH_SIZE]; 91 nd_ipv4 hsrp_virtaddr; 92 }; 93 94 void 95 hsrp_print(netdissect_options *ndo, const u_char *bp, u_int len) 96 { 97 const struct hsrp *hp = (const struct hsrp *) bp; 98 uint8_t version; 99 100 ndo->ndo_protocol = "hsrp"; 101 version = GET_U_1(hp->hsrp_version); 102 ND_PRINT("HSRPv%u", version); 103 if (version != 0) 104 return; 105 ND_PRINT("-"); 106 ND_PRINT("%s ", 107 tok2strary(op_code_str, "unknown (%u)", GET_U_1(hp->hsrp_op_code))); 108 ND_PRINT("%u: ", len); 109 ND_PRINT("state=%s ", 110 tok2str(states, "Unknown (%u)", GET_U_1(hp->hsrp_state))); 111 ND_PRINT("group=%u ", GET_U_1(hp->hsrp_group)); 112 if (GET_U_1(hp->hsrp_reserved) != 0) { 113 ND_PRINT("[reserved=%u!] ", GET_U_1(hp->hsrp_reserved)); 114 } 115 ND_PRINT("addr=%s", GET_IPADDR_STRING(hp->hsrp_virtaddr)); 116 if (ndo->ndo_vflag) { 117 ND_PRINT(" hellotime="); 118 unsigned_relts_print(ndo, GET_U_1(hp->hsrp_hellotime)); 119 ND_PRINT(" holdtime="); 120 unsigned_relts_print(ndo, GET_U_1(hp->hsrp_holdtime)); 121 ND_PRINT(" priority=%u", GET_U_1(hp->hsrp_priority)); 122 ND_PRINT(" auth=\""); 123 /* 124 * RFC 2281 Section 5.1 does not specify the encoding of 125 * Authentication Data explicitly, but zero padding can be 126 * inferred from the "recommended default value". 127 */ 128 nd_printjnp(ndo, hp->hsrp_authdata, HSRP_AUTH_SIZE); 129 ND_PRINT("\""); 130 } 131 } 132