1 /*
2 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. 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 * Format and print ntp packets.
22 * By Jeffrey Mogul/DECWRL
23 * loosely based on print-bootp.c
24 */
25
26 #ifndef lint
27 static const char rcsid[] _U_ =
28 "@(#) $Header: /tcpdump/master/tcpdump/print-ntp.c,v 1.41.2.1 2005/05/06 07:57:18 guy Exp $ (LBL)";
29 #endif
30
31 #ifdef HAVE_CONFIG_H
32 #include "config.h"
33 #endif
34
35 #include <tcpdump-stdinc.h>
36
37 #include <stdio.h>
38 #include <string.h>
39 #ifdef HAVE_STRFTIME
40 #include <time.h>
41 #endif
42
43 #include "interface.h"
44 #include "addrtoname.h"
45 #include "extract.h"
46 #ifdef MODEMASK
47 #undef MODEMASK /* Solaris sucks */
48 #endif
49 #include "ntp.h"
50
51 static void p_sfix(const struct s_fixedpt *);
52 static void p_ntp_time(const struct l_fixedpt *);
53 static void p_ntp_delta(const struct l_fixedpt *, const struct l_fixedpt *);
54
55 static struct tok ntp_mode_values[] = {
56 { MODE_UNSPEC, "unspecified" },
57 { MODE_SYM_ACT, "symmetric active" },
58 { MODE_SYM_PAS, "symmetric passive" },
59 { MODE_CLIENT, "Client" },
60 { MODE_SERVER, "Server" },
61 { MODE_BROADCAST, "Broadcast" },
62 { MODE_RES1, "Reserved" },
63 { MODE_RES2, "Reserved" },
64 { 0, NULL }
65 };
66
67 static struct tok ntp_leapind_values[] = {
68 { NO_WARNING, "" },
69 { PLUS_SEC, "+1s" },
70 { MINUS_SEC, "-1s" },
71 { ALARM, "clock unsynchronized" },
72 { 0, NULL }
73 };
74
75 /*
76 * Print ntp requests
77 */
78 void
ntp_print(register const u_char * cp,u_int length)79 ntp_print(register const u_char *cp, u_int length)
80 {
81 register const struct ntpdata *bp;
82 int mode, version, leapind;
83
84 bp = (struct ntpdata *)cp;
85
86 TCHECK(bp->status);
87
88 version = (int)(bp->status & VERSIONMASK) >> 3;
89 printf("NTPv%d", version);
90
91 mode = bp->status & MODEMASK;
92 if (!vflag) {
93 printf (", %s, length %u",
94 tok2str(ntp_mode_values, "Unknown mode", mode),
95 length);
96 return;
97 }
98
99 printf (", length %u\n\t%s",
100 length,
101 tok2str(ntp_mode_values, "Unknown mode", mode));
102
103 leapind = bp->status & LEAPMASK;
104 printf (", Leap indicator: %s (%u)",
105 tok2str(ntp_leapind_values, "Unknown", leapind),
106 leapind);
107
108 TCHECK(bp->stratum);
109 printf(", Stratum %u", bp->stratum);
110
111 TCHECK(bp->ppoll);
112 printf(", poll %us", bp->ppoll);
113
114 /* Can't TCHECK bp->precision bitfield so bp->distance + 0 instead */
115 TCHECK2(bp->root_delay, 0);
116 printf(", precision %d", bp->precision);
117
118 TCHECK(bp->root_delay);
119 fputs("\n\tRoot Delay: ", stdout);
120 p_sfix(&bp->root_delay);
121
122 TCHECK(bp->root_dispersion);
123 fputs(", Root dispersion: ", stdout);
124 p_sfix(&bp->root_dispersion);
125
126 TCHECK(bp->refid);
127 fputs(", Reference-ID: ", stdout);
128 /* Interpretation depends on stratum */
129 switch (bp->stratum) {
130
131 case UNSPECIFIED:
132 printf("(unspec)");
133 break;
134
135 case PRIM_REF:
136 if (fn_printn((u_char *)&(bp->refid), 4, snapend))
137 goto trunc;
138 break;
139
140 case INFO_QUERY:
141 printf("%s INFO_QUERY", ipaddr_string(&(bp->refid)));
142 /* this doesn't have more content */
143 return;
144
145 case INFO_REPLY:
146 printf("%s INFO_REPLY", ipaddr_string(&(bp->refid)));
147 /* this is too complex to be worth printing */
148 return;
149
150 default:
151 printf("%s", ipaddr_string(&(bp->refid)));
152 break;
153 }
154
155 TCHECK(bp->ref_timestamp);
156 fputs("\n\t Reference Timestamp: ", stdout);
157 p_ntp_time(&(bp->ref_timestamp));
158
159 TCHECK(bp->org_timestamp);
160 fputs("\n\t Originator Timestamp: ", stdout);
161 p_ntp_time(&(bp->org_timestamp));
162
163 TCHECK(bp->rec_timestamp);
164 fputs("\n\t Receive Timestamp: ", stdout);
165 p_ntp_time(&(bp->rec_timestamp));
166
167 TCHECK(bp->xmt_timestamp);
168 fputs("\n\t Transmit Timestamp: ", stdout);
169 p_ntp_time(&(bp->xmt_timestamp));
170
171 fputs("\n\t Originator - Receive Timestamp: ", stdout);
172 p_ntp_delta(&(bp->org_timestamp), &(bp->rec_timestamp));
173
174 fputs("\n\t Originator - Transmit Timestamp: ", stdout);
175 p_ntp_delta(&(bp->org_timestamp), &(bp->xmt_timestamp));
176
177 /* FIXME key-id, authentication */
178
179 return;
180
181 trunc:
182 fputs(" [|ntp]", stdout);
183 }
184
185 static void
p_sfix(register const struct s_fixedpt * sfp)186 p_sfix(register const struct s_fixedpt *sfp)
187 {
188 register int i;
189 register int f;
190 register float ff;
191
192 i = EXTRACT_16BITS(&sfp->int_part);
193 f = EXTRACT_16BITS(&sfp->fraction);
194 ff = f / 65536.0; /* shift radix point by 16 bits */
195 f = ff * 1000000.0; /* Treat fraction as parts per million */
196 printf("%d.%06d", i, f);
197 }
198
199 #define FMAXINT (4294967296.0) /* floating point rep. of MAXINT */
200
201 static void
p_ntp_time(register const struct l_fixedpt * lfp)202 p_ntp_time(register const struct l_fixedpt *lfp)
203 {
204 register int32_t i;
205 register u_int32_t uf;
206 register u_int32_t f;
207 register float ff;
208
209 i = EXTRACT_32BITS(&lfp->int_part);
210 uf = EXTRACT_32BITS(&lfp->fraction);
211 ff = uf;
212 if (ff < 0.0) /* some compilers are buggy */
213 ff += FMAXINT;
214 ff = ff / FMAXINT; /* shift radix point by 32 bits */
215 f = ff * 1000000000.0; /* treat fraction as parts per billion */
216 printf("%u.%09d", i, f);
217
218 #ifdef HAVE_STRFTIME
219 /*
220 * print the time in human-readable format.
221 */
222 if (i) {
223 time_t seconds = i - JAN_1970;
224 struct tm *tm;
225 char time_buf[128];
226
227 tm = localtime(&seconds);
228 strftime(time_buf, sizeof (time_buf), "%Y/%m/%d %H:%M:%S", tm);
229 printf (" (%s)", time_buf);
230 }
231 #endif
232 }
233
234 /* Prints time difference between *lfp and *olfp */
235 static void
p_ntp_delta(register const struct l_fixedpt * olfp,register const struct l_fixedpt * lfp)236 p_ntp_delta(register const struct l_fixedpt *olfp,
237 register const struct l_fixedpt *lfp)
238 {
239 register int32_t i;
240 register u_int32_t u, uf;
241 register u_int32_t ou, ouf;
242 register u_int32_t f;
243 register float ff;
244 int signbit;
245
246 u = EXTRACT_32BITS(&lfp->int_part);
247 ou = EXTRACT_32BITS(&olfp->int_part);
248 uf = EXTRACT_32BITS(&lfp->fraction);
249 ouf = EXTRACT_32BITS(&olfp->fraction);
250 if (ou == 0 && ouf == 0) {
251 p_ntp_time(lfp);
252 return;
253 }
254
255 i = u - ou;
256
257 if (i > 0) { /* new is definitely greater than old */
258 signbit = 0;
259 f = uf - ouf;
260 if (ouf > uf) /* must borrow from high-order bits */
261 i -= 1;
262 } else if (i < 0) { /* new is definitely less than old */
263 signbit = 1;
264 f = ouf - uf;
265 if (uf > ouf) /* must carry into the high-order bits */
266 i += 1;
267 i = -i;
268 } else { /* int_part is zero */
269 if (uf > ouf) {
270 signbit = 0;
271 f = uf - ouf;
272 } else {
273 signbit = 1;
274 f = ouf - uf;
275 }
276 }
277
278 ff = f;
279 if (ff < 0.0) /* some compilers are buggy */
280 ff += FMAXINT;
281 ff = ff / FMAXINT; /* shift radix point by 32 bits */
282 f = ff * 1000000000.0; /* treat fraction as parts per billion */
283 if (signbit)
284 putchar('-');
285 else
286 putchar('+');
287 printf("%d.%09d", i, f);
288 }
289
290