5 * Copyright (C) 2007-2012 Intel Corporation. All rights reserved.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
33 #include <sys/socket.h>
34 #include <netinet/in.h>
35 #include <netinet/ip.h>
36 #include <arpa/inet.h>
45 } __attribute__ ((packed));
50 } __attribute__ ((packed));
53 uint8_t flags; /* Mode, version and leap indicator */
54 uint8_t stratum; /* Stratum details */
55 int8_t poll; /* Maximum interval in log2 seconds */
56 int8_t precision; /* Clock precision in log2 seconds */
57 struct ntp_short rootdelay; /* Root delay */
58 struct ntp_short rootdisp; /* Root dispersion */
59 uint32_t refid; /* Reference ID */
60 struct ntp_time reftime; /* Reference timestamp */
61 struct ntp_time orgtime; /* Origin timestamp */
62 struct ntp_time rectime; /* Receive timestamp */
63 struct ntp_time xmttime; /* Transmit timestamp */
64 } __attribute__ ((packed));
66 #define OFFSET_1900_1970 2208988800UL /* 1970 - 1900 in seconds */
68 #define STEPTIME_MIN_OFFSET 0.128
70 #define LOGTOD(a) ((a) < 0 ? 1. / (1L << -(a)) : 1L << (int)(a))
72 static guint channel_watch = 0;
73 static struct timeval transmit_timeval;
74 static int transmit_fd = 0;
76 static char *timeserver = NULL;
77 static gint poll_id = 0;
78 static gint timeout_id = 0;
80 static void send_packet(int fd, const char *server)
83 struct sockaddr_in addr;
86 memset(&msg, 0, sizeof(msg));
90 msg.xmttime.seconds = random();
91 msg.xmttime.fraction = random();
93 memset(&addr, 0, sizeof(addr));
94 addr.sin_family = AF_INET;
95 addr.sin_port = htons(123);
96 addr.sin_addr.s_addr = inet_addr(server);
98 gettimeofday(&transmit_timeval, NULL);
100 len = sendto(fd, &msg, sizeof(msg), MSG_DONTWAIT,
101 &addr, sizeof(addr));
103 connman_error("Time request for server %s failed (%d/%s)",
104 server, errno, strerror(errno));
106 if (errno == ENETUNREACH)
107 __connman_timeserver_sync_next();
112 if (len != sizeof(msg)) {
113 connman_error("Broken time request for server %s", server);
118 static gboolean next_server(gpointer user_data)
120 if (timeserver != NULL) {
125 __connman_timeserver_sync_next();
130 static gboolean next_poll(gpointer user_data)
132 if (timeserver == NULL || transmit_fd == 0)
135 send_packet(transmit_fd, timeserver);
140 static void decode_msg(void *base, size_t len, struct timeval *tv)
142 struct ntp_msg *msg = base;
143 double org, rec, xmt, dst;
144 double delay, offset;
145 static guint transmit_delay;
147 if (len < sizeof(*msg)) {
148 connman_error("Invalid response from time server");
153 connman_error("Invalid packet timestamp from time server");
157 DBG("flags : 0x%02x", msg->flags);
158 DBG("stratum : %u", msg->stratum);
159 DBG("poll : %f seconds (%d)",
160 LOGTOD(msg->poll), msg->poll);
161 DBG("precision : %f seconds (%d)",
162 LOGTOD(msg->precision), msg->precision);
163 DBG("root delay : %u seconds (fraction %u)",
164 msg->rootdelay.seconds, msg->rootdelay.fraction);
165 DBG("root disp. : %u seconds (fraction %u)",
166 msg->rootdisp.seconds, msg->rootdisp.fraction);
167 DBG("reference : 0x%04x", msg->refid);
169 transmit_delay = LOGTOD(msg->poll);
171 if (msg->flags != 0x24)
174 org = transmit_timeval.tv_sec +
175 (1.0e-6 * transmit_timeval.tv_usec) + OFFSET_1900_1970;
176 rec = ntohl(msg->rectime.seconds) +
177 ((double) ntohl(msg->rectime.fraction) / UINT_MAX);
178 xmt = ntohl(msg->xmttime.seconds) +
179 ((double) ntohl(msg->xmttime.fraction) / UINT_MAX);
180 dst = tv->tv_sec + (1.0e-6 * tv->tv_usec) + OFFSET_1900_1970;
182 DBG("org=%f rec=%f xmt=%f dst=%f", org, rec, xmt, dst);
184 offset = ((rec - org) + (xmt - dst)) / 2;
185 delay = (dst - org) - (xmt - rec);
187 DBG("offset=%f delay=%f", offset, delay);
189 /* Remove the timeout, as timeserver has responded */
191 g_source_remove(timeout_id);
194 * Now poll the server every transmit_delay seconds
195 * for time correction.
198 g_source_remove(poll_id);
200 DBG("Timeserver %s, next sync in %d seconds", timeserver, transmit_delay);
202 poll_id = g_timeout_add_seconds(transmit_delay, next_poll, NULL);
204 connman_info("ntp: time slew %+.6f s", offset);
206 if (offset < STEPTIME_MIN_OFFSET && offset > -STEPTIME_MIN_OFFSET) {
209 adj.tv_sec = (long) offset;
210 adj.tv_usec = (offset - adj.tv_sec) * 1000000;
212 DBG("adjusting time");
214 if (adjtime(&adj, &adj) < 0) {
215 connman_error("Failed to adjust time");
219 DBG("%lu seconds, %lu msecs", adj.tv_sec, adj.tv_usec);
224 gettimeofday(&cur, NULL);
225 dtime = offset + cur.tv_sec + 1.0e-6 * cur.tv_usec;
226 cur.tv_sec = (long) dtime;
227 cur.tv_usec = (dtime - cur.tv_sec) * 1000000;
231 if (settimeofday(&cur, NULL) < 0) {
232 connman_error("Failed to set time");
236 DBG("%lu seconds, %lu msecs", cur.tv_sec, cur.tv_usec);
240 static gboolean received_data(GIOChannel *channel, GIOCondition condition,
243 unsigned char buf[128];
246 struct cmsghdr *cmsg;
252 if (condition & (G_IO_HUP | G_IO_ERR | G_IO_NVAL)) {
253 connman_error("Problem with timer server channel");
258 fd = g_io_channel_unix_get_fd(channel);
261 iov.iov_len = sizeof(buf);
263 memset(&msg, 0, sizeof(msg));
266 msg.msg_control = aux;
267 msg.msg_controllen = sizeof(aux);
269 len = recvmsg(fd, &msg, MSG_DONTWAIT);
275 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
276 if (cmsg->cmsg_level != SOL_SOCKET)
279 switch (cmsg->cmsg_type) {
281 tv = (struct timeval *) CMSG_DATA(cmsg);
286 decode_msg(iov.iov_base, iov.iov_len, tv);
291 static void start_ntp(char *server)
294 struct sockaddr_in addr;
295 int tos = IPTOS_LOWDELAY, timestamp = 1;
300 DBG("server %s", server);
302 if (channel_watch > 0)
305 transmit_fd = socket(PF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
306 if (transmit_fd < 0) {
307 connman_error("Failed to open time server socket");
311 memset(&addr, 0, sizeof(addr));
312 addr.sin_family = AF_INET;
314 if (bind(transmit_fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
315 connman_error("Failed to bind time server socket");
320 if (setsockopt(transmit_fd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0) {
321 connman_error("Failed to set type of service option");
326 if (setsockopt(transmit_fd, SOL_SOCKET, SO_TIMESTAMP, ×tamp,
327 sizeof(timestamp)) < 0) {
328 connman_error("Failed to enable timestamp support");
333 channel = g_io_channel_unix_new(transmit_fd);
334 if (channel == NULL) {
339 g_io_channel_set_encoding(channel, NULL, NULL);
340 g_io_channel_set_buffered(channel, FALSE);
342 g_io_channel_set_close_on_unref(channel, TRUE);
344 channel_watch = g_io_add_watch_full(channel, G_PRIORITY_DEFAULT,
345 G_IO_IN | G_IO_HUP | G_IO_ERR | G_IO_NVAL,
346 received_data, NULL, NULL);
348 g_io_channel_unref(channel);
351 send_packet(transmit_fd, server);
354 int __connman_ntp_start(char *server)
361 if (timeserver != NULL)
364 timeserver = g_strdup(server);
366 start_ntp(timeserver);
369 * Add a fallback timeout , preferably short, 5 sec here,
370 * to fallback on the next server.
373 timeout_id = g_timeout_add_seconds(5, next_server, NULL);
378 void __connman_ntp_stop()
383 g_source_remove(poll_id);
386 g_source_remove(timeout_id);
388 if (channel_watch > 0) {
389 g_source_remove(channel_watch);
394 if (timeserver != NULL) {