1 /*
2 * Copyright (c) 2000 Ben Smithurst <ben@scientia.demon.co.uk>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 */
21
22 /* \summary: Berkeley UNIX Time Synchronization Protocol */
23
24 /* specification: https://docs.freebsd.org/44doc/smm/12.timed/paper.pdf */
25
26 #include <config.h>
27
28 #include "netdissect-stdinc.h"
29
30 #include "netdissect.h"
31 #include "extract.h"
32
33 struct tsp_timeval {
34 nd_int32_t tv_sec;
35 nd_int32_t tv_usec;
36 };
37
38 struct tsp {
39 nd_uint8_t tsp_type;
40 nd_uint8_t tsp_vers;
41 nd_uint16_t tsp_seq;
42 union {
43 struct tsp_timeval tspu_time;
44 nd_int8_t tspu_hopcnt;
45 } tsp_u;
46 nd_byte tsp_name[256]; /* null-terminated string up to 256 */
47 };
48
49 #define tsp_time tsp_u.tspu_time
50 #define tsp_hopcnt tsp_u.tspu_hopcnt
51
52 /*
53 * Command types.
54 */
55 #define TSP_ANY 0 /* match any types */
56 #define TSP_ADJTIME 1 /* send adjtime */
57 #define TSP_ACK 2 /* generic acknowledgement */
58 #define TSP_MASTERREQ 3 /* ask for master's name */
59 #define TSP_MASTERACK 4 /* acknowledge master request */
60 #define TSP_SETTIME 5 /* send network time */
61 #define TSP_MASTERUP 6 /* inform slaves that master is up */
62 #define TSP_SLAVEUP 7 /* slave is up but not polled */
63 #define TSP_ELECTION 8 /* advance candidature for master */
64 #define TSP_ACCEPT 9 /* support candidature of master */
65 #define TSP_REFUSE 10 /* reject candidature of master */
66 #define TSP_CONFLICT 11 /* two or more masters present */
67 #define TSP_RESOLVE 12 /* masters' conflict resolution */
68 #define TSP_QUIT 13 /* reject candidature if master is up */
69 #define TSP_DATE 14 /* reset the time (date command) */
70 #define TSP_DATEREQ 15 /* remote request to reset the time */
71 #define TSP_DATEACK 16 /* acknowledge time setting */
72 #define TSP_TRACEON 17 /* turn tracing on */
73 #define TSP_TRACEOFF 18 /* turn tracing off */
74 #define TSP_MSITE 19 /* find out master's site */
75 #define TSP_MSITEREQ 20 /* remote master's site request */
76 #define TSP_TEST 21 /* for testing election algo */
77 #define TSP_SETDATE 22 /* New from date command */
78 #define TSP_SETDATEREQ 23 /* New remote for above */
79 #define TSP_LOOP 24 /* loop detection packet */
80 static const struct tok tsptype_str[] = {
81 { TSP_ANY, "TSP_ANY" },
82 { TSP_ADJTIME, "TSP_ADJTIME" },
83 { TSP_ACK, "TSP_ACK" },
84 { TSP_MASTERREQ, "TSP_MASTERREQ" },
85 { TSP_MASTERACK, "TSP_MASTERACK" },
86 { TSP_SETTIME, "TSP_SETTIME" },
87 { TSP_MASTERUP, "TSP_MASTERUP" },
88 { TSP_SLAVEUP, "TSP_SLAVEUP" },
89 { TSP_ELECTION, "TSP_ELECTION" },
90 { TSP_ACCEPT, "TSP_ACCEPT" },
91 { TSP_REFUSE, "TSP_REFUSE" },
92 { TSP_CONFLICT, "TSP_CONFLICT" },
93 { TSP_RESOLVE, "TSP_RESOLVE" },
94 { TSP_QUIT, "TSP_QUIT" },
95 { TSP_DATE, "TSP_DATE" },
96 { TSP_DATEREQ, "TSP_DATEREQ" },
97 { TSP_DATEACK, "TSP_DATEACK" },
98 { TSP_TRACEON, "TSP_TRACEON" },
99 { TSP_TRACEOFF, "TSP_TRACEOFF" },
100 { TSP_MSITE, "TSP_MSITE" },
101 { TSP_MSITEREQ, "TSP_MSITEREQ" },
102 { TSP_TEST, "TSP_TEST" },
103 { TSP_SETDATE, "TSP_SETDATE" },
104 { TSP_SETDATEREQ, "TSP_SETDATEREQ" },
105 { TSP_LOOP, "TSP_LOOP" },
106 { 0, NULL }
107 };
108
109 void
timed_print(netdissect_options * ndo,const u_char * bp)110 timed_print(netdissect_options *ndo,
111 const u_char *bp)
112 {
113 const struct tsp *tsp = (const struct tsp *)bp;
114 uint8_t tsp_type;
115 int sec, usec;
116
117 ndo->ndo_protocol = "timed";
118 tsp_type = GET_U_1(tsp->tsp_type);
119 ND_PRINT("%s", tok2str(tsptype_str, "(tsp_type %#x)", tsp_type));
120
121 ND_PRINT(" vers %u", GET_U_1(tsp->tsp_vers));
122
123 ND_PRINT(" seq %u", GET_BE_U_2(tsp->tsp_seq));
124
125 switch (tsp_type) {
126 case TSP_LOOP:
127 ND_PRINT(" hopcnt %u", GET_U_1(tsp->tsp_hopcnt));
128 break;
129 case TSP_SETTIME:
130 case TSP_ADJTIME:
131 case TSP_SETDATE:
132 case TSP_SETDATEREQ:
133 sec = GET_BE_S_4(tsp->tsp_time.tv_sec);
134 usec = GET_BE_S_4(tsp->tsp_time.tv_usec);
135 /* XXX The comparison below is always false? */
136 if (usec < 0)
137 /* invalid, skip the rest of the packet */
138 return;
139 ND_PRINT(" time ");
140 if (sec < 0 && usec != 0) {
141 sec++;
142 if (sec == 0)
143 ND_PRINT("-");
144 usec = 1000000 - usec;
145 }
146 ND_PRINT("%d.%06d", sec, usec);
147 break;
148 }
149 ND_PRINT(" name ");
150 nd_printjnp(ndo, tsp->tsp_name, sizeof(tsp->tsp_name));
151 }
152