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 /* Cisco Hot Standby Router Protocol (HSRP). */
33
34 #ifdef HAVE_CONFIG_H
35 #include "config.h"
36 #endif
37
38 #include <netdissect-stdinc.h>
39
40 #include "netdissect.h"
41 #include "addrtoname.h"
42
43 /* HSRP op code types. */
44 static const char *op_code_str[] = {
45 "hello",
46 "coup",
47 "resign"
48 };
49
50 /* HSRP states and associated names. */
51 static const struct tok states[] = {
52 { 0, "initial" },
53 { 1, "learn" },
54 { 2, "listen" },
55 { 4, "speak" },
56 { 8, "standby" },
57 { 16, "active" },
58 { 0, NULL }
59 };
60
61 /*
62 * RFC 2281:
63 *
64 * 0 1 2 3
65 * 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
66 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
67 * | Version | Op Code | State | Hellotime |
68 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
69 * | Holdtime | Priority | Group | Reserved |
70 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71 * | Authentication Data |
72 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73 * | Authentication Data |
74 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
75 * | Virtual IP Address |
76 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
77 */
78
79 #define HSRP_AUTH_SIZE 8
80
81 /* HSRP protocol header. */
82 struct hsrp {
83 uint8_t hsrp_version;
84 uint8_t hsrp_op_code;
85 uint8_t hsrp_state;
86 uint8_t hsrp_hellotime;
87 uint8_t hsrp_holdtime;
88 uint8_t hsrp_priority;
89 uint8_t hsrp_group;
90 uint8_t hsrp_reserved;
91 uint8_t hsrp_authdata[HSRP_AUTH_SIZE];
92 struct in_addr hsrp_virtaddr;
93 };
94
95 void
hsrp_print(netdissect_options * ndo,register const uint8_t * bp,register u_int len)96 hsrp_print(netdissect_options *ndo, register const uint8_t *bp, register u_int len)
97 {
98 const struct hsrp *hp = (const struct hsrp *) bp;
99
100 ND_TCHECK(hp->hsrp_version);
101 ND_PRINT((ndo, "HSRPv%d", hp->hsrp_version));
102 if (hp->hsrp_version != 0)
103 return;
104 ND_TCHECK(hp->hsrp_op_code);
105 ND_PRINT((ndo, "-"));
106 ND_PRINT((ndo, "%s ", tok2strary(op_code_str, "unknown (%d)", hp->hsrp_op_code)));
107 ND_PRINT((ndo, "%d: ", len));
108 ND_TCHECK(hp->hsrp_state);
109 ND_PRINT((ndo, "state=%s ", tok2str(states, "Unknown (%d)", hp->hsrp_state)));
110 ND_TCHECK(hp->hsrp_group);
111 ND_PRINT((ndo, "group=%d ", hp->hsrp_group));
112 ND_TCHECK(hp->hsrp_reserved);
113 if (hp->hsrp_reserved != 0) {
114 ND_PRINT((ndo, "[reserved=%d!] ", hp->hsrp_reserved));
115 }
116 ND_TCHECK(hp->hsrp_virtaddr);
117 ND_PRINT((ndo, "addr=%s", ipaddr_string(ndo, &hp->hsrp_virtaddr)));
118 if (ndo->ndo_vflag) {
119 ND_PRINT((ndo, " hellotime="));
120 unsigned_relts_print(ndo, hp->hsrp_hellotime);
121 ND_PRINT((ndo, " holdtime="));
122 unsigned_relts_print(ndo, hp->hsrp_holdtime);
123 ND_PRINT((ndo, " priority=%d", hp->hsrp_priority));
124 ND_PRINT((ndo, " auth=\""));
125 if (fn_printn(ndo, hp->hsrp_authdata, sizeof(hp->hsrp_authdata),
126 ndo->ndo_snapend)) {
127 ND_PRINT((ndo, "\""));
128 goto trunc;
129 }
130 ND_PRINT((ndo, "\""));
131 }
132 return;
133 trunc:
134 ND_PRINT((ndo, "[|hsrp]"));
135 }
136