1 /* $OpenBSD: print-ntp.c,v 1.20 2021/12/01 18:28:46 deraadt Exp $ */
2
3 /*
4 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that: (1) source code distributions
9 * retain the above copyright notice and this paragraph in its entirety, (2)
10 * distributions including binary code include the above copyright notice and
11 * this paragraph in its entirety in the documentation or other materials
12 * provided with the distribution, and (3) all advertising materials mentioning
13 * features or use of this software display the following acknowledgement:
14 * ``This product includes software developed by the University of California,
15 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16 * the University nor the names of its contributors may be used to endorse
17 * or promote products derived from this software without specific prior
18 * written permission.
19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22 *
23 * Format and print ntp packets.
24 * By Jeffrey Mogul/DECWRL
25 * loosely based on print-bootp.c
26 */
27
28 #include <sys/time.h>
29 #include <sys/socket.h>
30
31 #include <net/if.h>
32
33 #include <netinet/in.h>
34 #include <netinet/if_ether.h>
35
36 #include <ctype.h>
37 #include <stdio.h>
38 #include <string.h>
39
40 #include "interface.h"
41 #include "addrtoname.h"
42 #ifdef MODEMASK
43 #undef MODEMASK /* Solaris sucks */
44 #endif
45 #include "ntp.h"
46
47 static void p_sfix(const struct s_fixedpt *);
48 static void p_ntp_time(const struct l_fixedpt *);
49 static void p_ntp_delta(const struct l_fixedpt *, const struct l_fixedpt *);
50
51 /*
52 * Print ntp requests
53 */
54 void
ntp_print(const u_char * cp,u_int length)55 ntp_print(const u_char *cp, u_int length)
56 {
57 const struct ntpdata *bp;
58 int mode, version, leapind;
59
60 bp = (struct ntpdata *)cp;
61 /* Note funny sized packets */
62 if (length != sizeof(struct ntpdata))
63 printf(" [len=%d]", length);
64
65 TCHECK(bp->status);
66
67 version = (int)(bp->status & VERSIONMASK) >> 3;
68 printf("v%d", version);
69
70 leapind = bp->status & LEAPMASK;
71 switch (leapind) {
72
73 case NO_WARNING:
74 break;
75
76 case ALARM:
77 printf(" alarm");
78 break;
79
80 case PLUS_SEC:
81 printf(" +1s");
82 break;
83
84 case MINUS_SEC:
85 printf(" -1s");
86 break;
87 }
88
89 mode = bp->status & MODEMASK;
90 switch (mode) {
91
92 case MODE_UNSPEC: /* unspecified */
93 printf(" unspec");
94 break;
95
96 case MODE_SYM_ACT: /* symmetric active */
97 printf(" sym_act");
98 break;
99
100 case MODE_SYM_PAS: /* symmetric passive */
101 printf(" sym_pas");
102 break;
103
104 case MODE_CLIENT: /* client */
105 printf(" client");
106 break;
107
108 case MODE_SERVER: /* server */
109 printf(" server");
110 break;
111
112 case MODE_BROADCAST: /* broadcast */
113 printf(" bcast");
114 break;
115
116 case MODE_RES1: /* reserved */
117 printf(" res1");
118 break;
119
120 case MODE_RES2: /* reserved */
121 printf(" res2");
122 break;
123
124 }
125
126 TCHECK(bp->stratum);
127 printf(" strat %d", bp->stratum);
128
129 TCHECK(bp->ppoll);
130 printf(" poll %d", bp->ppoll);
131
132 /* Can't TCHECK bp->precision bitfield so bp->distance + 0 instead */
133 TCHECK2(bp->distance, 0);
134 printf(" prec %d", bp->precision);
135
136 if (!vflag)
137 return;
138
139 TCHECK(bp->distance);
140 printf(" dist ");
141 p_sfix(&bp->distance);
142
143 TCHECK(bp->dispersion);
144 printf(" disp ");
145 p_sfix(&bp->dispersion);
146
147 TCHECK(bp->refid);
148 printf(" ref ");
149 /* Interpretation depends on stratum */
150 switch (bp->stratum) {
151
152 case UNSPECIFIED:
153 printf("(unspec)");
154 break;
155
156 case PRIM_REF:
157 fn_printn((u_char *)&bp->refid, sizeof(bp->refid), NULL);
158 break;
159
160 case INFO_QUERY:
161 printf("%s INFO_QUERY", ipaddr_string(&(bp->refid)));
162 /* this doesn't have more content */
163 return;
164
165 case INFO_REPLY:
166 printf("%s INFO_REPLY", ipaddr_string(&(bp->refid)));
167 /* this is too complex to be worth printing */
168 return;
169
170 default:
171 printf("%s", ipaddr_string(&(bp->refid)));
172 break;
173 }
174
175 TCHECK(bp->reftime);
176 putchar('@');
177 p_ntp_time(&(bp->reftime));
178
179 TCHECK(bp->org);
180 printf(" orig ");
181 p_ntp_time(&(bp->org));
182
183 TCHECK(bp->rec);
184 printf(" rec ");
185 p_ntp_delta(&(bp->org), &(bp->rec));
186
187 TCHECK(bp->xmt);
188 printf(" xmt ");
189 p_ntp_delta(&(bp->org), &(bp->xmt));
190
191 return;
192
193 trunc:
194 printf(" [|ntp]");
195 }
196
197 static void
p_sfix(const struct s_fixedpt * sfp)198 p_sfix(const struct s_fixedpt *sfp)
199 {
200 int i;
201 int f;
202 float ff;
203
204 i = ntohs(sfp->int_part);
205 f = ntohs(sfp->fraction);
206 ff = f / 65536.0; /* shift radix point by 16 bits */
207 f = ff * 1000000.0; /* Treat fraction as parts per million */
208 printf("%d.%06d", i, f);
209 }
210
211 #define FMAXINT (4294967296.0) /* floating point rep. of MAXINT */
212
213 static void
p_ntp_time(const struct l_fixedpt * lfp)214 p_ntp_time(const struct l_fixedpt *lfp)
215 {
216 int32_t i;
217 u_int32_t uf;
218 u_int32_t f;
219 float ff;
220
221 i = ntohl(lfp->int_part);
222 uf = ntohl(lfp->fraction);
223 ff = uf;
224 if (ff < 0.0) /* some compilers are buggy */
225 ff += FMAXINT;
226 ff = ff / FMAXINT; /* shift radix point by 32 bits */
227 f = ff * 1000000000.0; /* treat fraction as parts per billion */
228 printf("%u.%09d", i, f);
229 }
230
231 /* Prints time difference between *lfp and *olfp */
232 static void
p_ntp_delta(const struct l_fixedpt * olfp,const struct l_fixedpt * lfp)233 p_ntp_delta(const struct l_fixedpt *olfp, const struct l_fixedpt *lfp)
234 {
235 int32_t i;
236 u_int32_t uf;
237 u_int32_t ouf;
238 u_int32_t f;
239 float ff;
240 int signbit;
241
242 i = ntohl(lfp->int_part) - ntohl(olfp->int_part);
243
244 uf = ntohl(lfp->fraction);
245 ouf = ntohl(olfp->fraction);
246
247 if (i > 0) { /* new is definitely greater than old */
248 signbit = 0;
249 f = uf - ouf;
250 if (ouf > uf) /* must borrow from high-order bits */
251 i -= 1;
252 } else if (i < 0) { /* new is definitely less than old */
253 signbit = 1;
254 f = ouf - uf;
255 if (uf > ouf) /* must carry into the high-order bits */
256 i += 1;
257 i = -i;
258 } else { /* int_part is zero */
259 if (uf > ouf) {
260 signbit = 0;
261 f = uf - ouf;
262 } else {
263 signbit = 1;
264 f = ouf - uf;
265 }
266 }
267
268 ff = f;
269 if (ff < 0.0) /* some compilers are buggy */
270 ff += FMAXINT;
271 ff = ff / FMAXINT; /* shift radix point by 32 bits */
272 f = ff * 1000000000.0; /* treat fraction as parts per billion */
273 if (signbit)
274 putchar('-');
275 else
276 putchar('+');
277 printf("%d.%09d", i, f);
278 }
279