xref: /freebsd/contrib/tcpdump/print-timed.c (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
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
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