1 /* $OpenBSD: sensors.c,v 1.45 2010/04/20 20:49:36 deraadt Exp $ */ 2 3 /* 4 * Copyright (c) 2006 Henning Brauer <henning@openbsd.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 MIND, USE, DATA OR PROFITS, WHETHER 15 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 16 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/param.h> 20 #include <sys/queue.h> 21 #include <sys/sensors.h> 22 #include <sys/sysctl.h> 23 #include <sys/device.h> 24 #include <sys/hotplug.h> 25 26 #include <errno.h> 27 #include <fcntl.h> 28 #include <stdio.h> 29 #include <stdlib.h> 30 #include <string.h> 31 #include <unistd.h> 32 33 #include "ntpd.h" 34 35 #define MAXDEVNAMLEN 16 36 #define _PATH_DEV_HOTPLUG "/dev/hotplug" 37 38 int sensor_probe(int, char *, struct sensor *); 39 void sensor_add(int, char *); 40 void sensor_remove(struct ntp_sensor *); 41 void sensor_update(struct ntp_sensor *); 42 43 void 44 sensor_init(void) 45 { 46 TAILQ_INIT(&conf->ntp_sensors); 47 } 48 49 int 50 sensor_scan(void) 51 { 52 int i, n, err; 53 char d[MAXDEVNAMLEN]; 54 struct sensor s; 55 56 n = 0; 57 for (i = 0; ; i++) 58 if ((err = sensor_probe(i, d, &s))) { 59 if (err == 0) 60 continue; 61 if (err == -1) /* no further sensors */ 62 break; 63 sensor_add(i, d); 64 n++; 65 } 66 67 return n; 68 } 69 70 /* 71 * 1 = time sensor! 72 * 0 = sensor exists... but is not a time sensor 73 * -1: no sensor here, and no further sensors after this 74 */ 75 int 76 sensor_probe(int devid, char *dxname, struct sensor *sensor) 77 { 78 int mib[5]; 79 size_t slen, sdlen; 80 struct sensordev sensordev; 81 82 mib[0] = CTL_HW; 83 mib[1] = HW_SENSORS; 84 mib[2] = devid; 85 mib[3] = SENSOR_TIMEDELTA; 86 mib[4] = 0; 87 88 sdlen = sizeof(sensordev); 89 if (sysctl(mib, 3, &sensordev, &sdlen, NULL, 0) == -1) { 90 if (errno == ENXIO) 91 return (0); 92 if (errno == ENOENT) 93 return (-1); 94 log_warn("sensor_probe sysctl"); 95 } 96 97 if (sensordev.maxnumt[SENSOR_TIMEDELTA] == 0) 98 return (0); 99 100 strlcpy(dxname, sensordev.xname, MAXDEVNAMLEN); 101 102 slen = sizeof(*sensor); 103 if (sysctl(mib, 5, sensor, &slen, NULL, 0) == -1) { 104 if (errno != ENOENT) 105 log_warn("sensor_probe sysctl"); 106 return (0); 107 } 108 109 return (1); 110 } 111 112 void 113 sensor_add(int sensordev, char *dxname) 114 { 115 struct ntp_sensor *s; 116 struct ntp_conf_sensor *cs; 117 118 /* check whether it is already there */ 119 TAILQ_FOREACH(s, &conf->ntp_sensors, entry) 120 if (!strcmp(s->device, dxname)) 121 return; 122 123 /* check whether it is requested in the config file */ 124 for (cs = TAILQ_FIRST(&conf->ntp_conf_sensors); cs != NULL && 125 strcmp(cs->device, dxname) && strcmp(cs->device, "*"); 126 cs = TAILQ_NEXT(cs, entry)) 127 ; /* nothing */ 128 if (cs == NULL) 129 return; 130 131 if ((s = calloc(1, sizeof(*s))) == NULL) 132 fatal("sensor_add calloc"); 133 134 s->next = getmonotime(); 135 s->weight = cs->weight; 136 s->correction = cs->correction; 137 if ((s->device = strdup(dxname)) == NULL) 138 fatal("sensor_add strdup"); 139 s->sensordevid = sensordev; 140 141 if (cs->refstr == NULL) 142 memcpy(&s->refid, "HARD", sizeof(s->refid)); 143 else { 144 s->refid = 0; 145 strncpy((char *)&s->refid, cs->refstr, sizeof(s->refid)); 146 } 147 148 TAILQ_INSERT_TAIL(&conf->ntp_sensors, s, entry); 149 150 log_debug("sensor %s added (weight %d, correction %.6f, refstr %.4s)", 151 s->device, s->weight, s->correction / 1e6, &s->refid); 152 } 153 154 void 155 sensor_remove(struct ntp_sensor *s) 156 { 157 TAILQ_REMOVE(&conf->ntp_sensors, s, entry); 158 free(s->device); 159 free(s); 160 } 161 162 void 163 sensor_query(struct ntp_sensor *s) 164 { 165 char dxname[MAXDEVNAMLEN]; 166 struct sensor sensor; 167 168 if (conf->settime) 169 s->next = getmonotime() + SENSOR_QUERY_INTERVAL_SETTIME; 170 else 171 s->next = getmonotime() + SENSOR_QUERY_INTERVAL; 172 173 /* rcvd is walltime here, monotime in client.c. not used elsewhere */ 174 if (s->update.rcvd < time(NULL) - SENSOR_DATA_MAXAGE) 175 s->update.good = 0; 176 177 if (!sensor_probe(s->sensordevid, dxname, &sensor)) { 178 sensor_remove(s); 179 return; 180 } 181 182 if (sensor.flags & SENSOR_FINVALID || 183 sensor.status != SENSOR_S_OK) 184 return; 185 186 if (strcmp(dxname, s->device)) { 187 sensor_remove(s); 188 return; 189 } 190 191 if (sensor.tv.tv_sec == s->last) /* already seen */ 192 return; 193 194 s->last = sensor.tv.tv_sec; 195 /* 196 * TD = device time 197 * TS = system time 198 * sensor.value = TS - TD in ns 199 * if value is positive, system time is ahead 200 */ 201 s->offsets[s->shift].offset = (sensor.value / -1e9) - getoffset() + 202 (s->correction / 1e6); 203 s->offsets[s->shift].rcvd = sensor.tv.tv_sec; 204 s->offsets[s->shift].good = 1; 205 206 s->offsets[s->shift].status.send_refid = s->refid; 207 s->offsets[s->shift].status.stratum = 0; /* increased when sent out */ 208 s->offsets[s->shift].status.rootdelay = 0; 209 s->offsets[s->shift].status.rootdispersion = 0; 210 s->offsets[s->shift].status.reftime = sensor.tv.tv_sec; 211 s->offsets[s->shift].status.synced = 1; 212 213 log_debug("sensor %s: offset %f", s->device, 214 s->offsets[s->shift].offset); 215 216 if (++s->shift >= SENSOR_OFFSETS) { 217 s->shift = 0; 218 sensor_update(s); 219 } 220 221 } 222 223 void 224 sensor_update(struct ntp_sensor *s) 225 { 226 struct ntp_offset **offsets; 227 int i; 228 229 if ((offsets = calloc(SENSOR_OFFSETS, sizeof(struct ntp_offset *))) == 230 NULL) 231 fatal("calloc sensor_update"); 232 233 for (i = 0; i < SENSOR_OFFSETS; i++) 234 offsets[i] = &s->offsets[i]; 235 236 qsort(offsets, SENSOR_OFFSETS, sizeof(struct ntp_offset *), 237 offset_compare); 238 239 i = SENSOR_OFFSETS / 2; 240 memcpy(&s->update, offsets[i], sizeof(s->update)); 241 if (SENSOR_OFFSETS % 2 == 0) { 242 s->update.offset = 243 (offsets[i - 1]->offset + offsets[i]->offset) / 2; 244 } 245 free(offsets); 246 247 log_debug("sensor update %s: offset %f", s->device, s->update.offset); 248 priv_adjtime(); 249 } 250 251 int 252 sensor_hotplugfd(void) 253 { 254 #ifdef notyet 255 int fd, flags; 256 257 if ((fd = open(_PATH_DEV_HOTPLUG, O_RDONLY, 0)) == -1) { 258 log_warn("open %s", _PATH_DEV_HOTPLUG); 259 return (-1); 260 } 261 262 if ((flags = fcntl(fd, F_GETFL, 0)) == -1) 263 fatal("fcntl F_GETFL"); 264 flags |= O_NONBLOCK; 265 if ((flags = fcntl(fd, F_SETFL, flags)) == -1) 266 fatal("fcntl F_SETFL"); 267 268 return (fd); 269 #else 270 return (-1); 271 #endif 272 } 273 274 void 275 sensor_hotplugevent(int fd) 276 { 277 struct hotplug_event he; 278 ssize_t n; 279 280 do { 281 if ((n = read(fd, &he, sizeof(he))) == -1 && 282 errno != EINTR && errno != EAGAIN) 283 fatal("sensor_hotplugevent read"); 284 285 if (n == sizeof(he)) 286 switch (he.he_type) { 287 case HOTPLUG_DEVAT: 288 if (he.he_devclass == DV_DULL && 289 !strcmp(he.he_devname, "sensordev")) 290 sensor_scan(); 291 break; 292 default: /* ignore */ 293 break; 294 } 295 else if (n > 0) 296 fatal("sensor_hotplugevent: short read"); 297 } while (n > 0 || (n == -1 && errno == EINTR)); 298 } 299