1 /* $OpenBSD: util.c,v 1.28 2023/12/20 15:36:36 otto Exp $ */
2
3 /*
4 * Copyright (c) 2004 Alexander Guy <alexander.guy@andern.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <fcntl.h>
20 #include <limits.h>
21 #include <stdint.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <time.h>
25 #include <unistd.h>
26
27 #include "ntpd.h"
28
29 double
gettime_corrected(void)30 gettime_corrected(void)
31 {
32 return (gettime() + getoffset());
33 }
34
35 double
getoffset(void)36 getoffset(void)
37 {
38 struct timeval tv;
39 if (adjtime(NULL, &tv) == -1)
40 return (0.0);
41 return (tv.tv_sec + 1.0e-6 * tv.tv_usec);
42 }
43
44 double
gettime(void)45 gettime(void)
46 {
47 struct timeval tv;
48
49 if (gettimeofday(&tv, NULL) == -1)
50 fatal("gettimeofday");
51
52 return (gettime_from_timeval(&tv));
53 }
54
55 double
gettime_from_timeval(struct timeval * tv)56 gettime_from_timeval(struct timeval *tv)
57 {
58 /*
59 * Account for overflow on OSes that have a 32-bit time_t.
60 */
61 return ((uint64_t)tv->tv_sec + JAN_1970 + 1.0e-6 * tv->tv_usec);
62 }
63
64 time_t
getmonotime(void)65 getmonotime(void)
66 {
67 struct timespec ts;
68
69 if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0)
70 fatal("clock_gettime");
71
72 return (ts.tv_sec);
73 }
74
75
76 void
d_to_tv(double d,struct timeval * tv)77 d_to_tv(double d, struct timeval *tv)
78 {
79 tv->tv_sec = d;
80 tv->tv_usec = (d - tv->tv_sec) * 1000000;
81 while (tv->tv_usec < 0) {
82 tv->tv_usec += 1000000;
83 tv->tv_sec -= 1;
84 }
85 }
86
87 double
lfp_to_d(struct l_fixedpt lfp)88 lfp_to_d(struct l_fixedpt lfp)
89 {
90 double base, ret;
91
92 lfp.int_partl = ntohl(lfp.int_partl);
93 lfp.fractionl = ntohl(lfp.fractionl);
94
95 /* see comment in ntp.h */
96 base = NTP_ERA;
97 if (lfp.int_partl <= INT32_MAX)
98 base++;
99 ret = base * SECS_IN_ERA;
100 ret += (double)(lfp.int_partl) + ((double)lfp.fractionl / L_DENOMINATOR);
101
102 return (ret);
103 }
104
105 struct l_fixedpt
d_to_lfp(double d)106 d_to_lfp(double d)
107 {
108 struct l_fixedpt lfp;
109
110 while (d > SECS_IN_ERA)
111 d -= SECS_IN_ERA;
112 lfp.int_partl = htonl((u_int32_t)d);
113 lfp.fractionl = htonl((u_int32_t)((d - (u_int32_t)d) * L_DENOMINATOR));
114
115 return (lfp);
116 }
117
118 double
sfp_to_d(struct s_fixedpt sfp)119 sfp_to_d(struct s_fixedpt sfp)
120 {
121 double ret;
122
123 sfp.int_parts = ntohs(sfp.int_parts);
124 sfp.fractions = ntohs(sfp.fractions);
125
126 ret = (double)(sfp.int_parts) + ((double)sfp.fractions / S_DENOMINATOR);
127
128 return (ret);
129 }
130
131 struct s_fixedpt
d_to_sfp(double d)132 d_to_sfp(double d)
133 {
134 struct s_fixedpt sfp;
135
136 sfp.int_parts = htons((u_int16_t)d);
137 sfp.fractions = htons((u_int16_t)((d - (u_int16_t)d) * S_DENOMINATOR));
138
139 return (sfp);
140 }
141
142 char *
print_rtable(int r)143 print_rtable(int r)
144 {
145 static char b[11];
146
147 b[0] = 0;
148 if (r > 0)
149 snprintf(b, sizeof(b), "rtable %d", r);
150
151 return (b);
152 }
153
154 const char *
log_sockaddr(struct sockaddr * sa)155 log_sockaddr(struct sockaddr *sa)
156 {
157 static char buf[NI_MAXHOST];
158
159 if (getnameinfo(sa, SA_LEN(sa), buf, sizeof(buf), NULL, 0,
160 NI_NUMERICHOST))
161 return ("(unknown)");
162 else
163 return (buf);
164 }
165
166 const char *
log_ntp_addr(struct ntp_addr * addr)167 log_ntp_addr(struct ntp_addr *addr)
168 {
169 if (addr == NULL)
170 return ("(unknown)");
171 return log_sockaddr((struct sockaddr *)&addr->ss);
172 }
173
174 pid_t
start_child(char * pname,int cfd,int argc,char ** argv)175 start_child(char *pname, int cfd, int argc, char **argv)
176 {
177 char **nargv;
178 int nargc, i;
179 pid_t pid;
180
181 /* Prepare the child process new argv. */
182 nargv = calloc(argc + 3, sizeof(char *));
183 if (nargv == NULL)
184 fatal("%s: calloc", __func__);
185
186 /* Copy the program name first. */
187 nargc = 0;
188 nargv[nargc++] = argv[0];
189
190 /* Set the process name and copy the original args. */
191 nargv[nargc++] = "-P";
192 nargv[nargc++] = pname;
193 for (i = 1; i < argc; i++)
194 nargv[nargc++] = argv[i];
195
196 nargv[nargc] = NULL;
197
198 switch (pid = fork()) {
199 case -1:
200 fatal("%s: fork", __func__);
201 break;
202 case 0:
203 /* Prepare the parent socket and execute. */
204 if (cfd != PARENT_SOCK_FILENO) {
205 if (dup2(cfd, PARENT_SOCK_FILENO) == -1)
206 fatal("dup2");
207 } else if (fcntl(cfd, F_SETFD, 0) == -1)
208 fatal("fcntl");
209
210 execvp(argv[0], nargv);
211 fatal("%s: execvp", __func__);
212 break;
213
214 default:
215 /* Close child's socket end. */
216 close(cfd);
217 break;
218 }
219
220 free(nargv);
221 return (pid);
222 }
223
224 int
sanitize_argv(int * argc,char *** argv)225 sanitize_argv(int *argc, char ***argv)
226 {
227 char **nargv;
228 int nargc;
229 int i;
230
231 /*
232 * We need at least three arguments:
233 * Example: '/usr/sbin/ntpd' '-P' 'foobar'.
234 */
235 if (*argc < 3)
236 return (-1);
237
238 *argc -= 2;
239
240 /* Allocate new arguments vector and copy pointers. */
241 nargv = calloc((*argc) + 1, sizeof(char *));
242 if (nargv == NULL)
243 return (-1);
244
245 nargc = 0;
246 nargv[nargc++] = (*argv)[0];
247 for (i = 1; i < *argc; i++)
248 nargv[nargc++] = (*argv)[i + 2];
249
250 nargv[nargc] = NULL;
251 *argv = nargv;
252 return (0);
253 }
254