5 * Copyright (C) 2007-2010 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;
79 static void send_packet(int fd, const char *server)
82 struct sockaddr_in addr;
85 memset(&msg, 0, sizeof(msg));
89 msg.xmttime.seconds = random();
90 msg.xmttime.fraction = random();
92 memset(&addr, 0, sizeof(addr));
93 addr.sin_family = AF_INET;
94 addr.sin_port = htons(123);
95 addr.sin_addr.s_addr = inet_addr(server);
97 gettimeofday(&transmit_timeval, NULL);
99 len = sendto(fd, &msg, sizeof(msg), MSG_DONTWAIT,
100 &addr, sizeof(addr));
102 connman_error("Time request for server %s failed", server);
106 if (len != sizeof(msg)) {
107 connman_error("Broken time request for server %s", server);
112 static gboolean next_poll(gpointer user_data)
114 if (timeserver == NULL || transmit_fd == 0)
117 send_packet(transmit_fd, timeserver);
122 static void decode_msg(void *base, size_t len, struct timeval *tv)
124 struct ntp_msg *msg = base;
125 double org, rec, xmt, dst;
126 double delay, offset;
127 static guint transmit_delay;
129 if (len < sizeof(*msg)) {
130 connman_error("Invalid response from time server");
135 connman_error("Invalid packet timestamp from time server");
139 DBG("flags : 0x%02x", msg->flags);
140 DBG("stratum : %u", msg->stratum);
141 DBG("poll : %f seconds (%d)",
142 LOGTOD(msg->poll), msg->poll);
143 DBG("precision : %f seconds (%d)",
144 LOGTOD(msg->precision), msg->precision);
145 DBG("root delay : %u seconds (fraction %u)",
146 msg->rootdelay.seconds, msg->rootdelay.fraction);
147 DBG("root disp. : %u seconds (fraction %u)",
148 msg->rootdisp.seconds, msg->rootdisp.fraction);
149 DBG("reference : 0x%04x", msg->refid);
151 transmit_delay = LOGTOD(msg->poll);
153 if (msg->flags != 0x24)
156 org = transmit_timeval.tv_sec +
157 (1.0e-6 * transmit_timeval.tv_usec) + OFFSET_1900_1970;
158 rec = ntohl(msg->rectime.seconds) +
159 ((double) ntohl(msg->rectime.fraction) / UINT_MAX);
160 xmt = ntohl(msg->xmttime.seconds) +
161 ((double) ntohl(msg->xmttime.fraction) / UINT_MAX);
162 dst = tv->tv_sec + (1.0e-6 * tv->tv_usec) + OFFSET_1900_1970;
164 DBG("org=%f rec=%f xmt=%f dst=%f", org, rec, xmt, dst);
166 offset = ((rec - org) + (xmt - dst)) / 2;
167 delay = (dst - org) - (xmt - rec);
169 DBG("offset=%f delay=%f", offset, delay);
171 /* Timeserver has responded.
172 * Now poll the server every transmit_delay seconds
173 * for time correction.
176 g_source_remove(poll_id);
178 DBG("Timeserver %s, next sync in %d seconds", timeserver, transmit_delay);
180 poll_id = g_timeout_add_seconds(transmit_delay, next_poll, NULL);
182 if (offset < STEPTIME_MIN_OFFSET && offset > -STEPTIME_MIN_OFFSET) {
185 adj.tv_sec = (long) offset;
186 adj.tv_usec = (offset - adj.tv_sec) * 1000000;
188 DBG("adjusting time");
190 if (adjtime(&adj, &adj) < 0) {
191 connman_error("Failed to adjust time");
195 DBG("%lu seconds, %lu msecs", adj.tv_sec, adj.tv_usec);
200 gettimeofday(&cur, NULL);
201 dtime = offset + cur.tv_sec + 1.0e-6 * cur.tv_usec;
202 cur.tv_sec = (long) dtime;
203 cur.tv_usec = (dtime - cur.tv_sec) * 1000000;
207 if (settimeofday(&cur, NULL) < 0) {
208 connman_error("Failed to set time");
212 DBG("%lu seconds, %lu msecs", cur.tv_sec, cur.tv_usec);
216 static gboolean received_data(GIOChannel *channel, GIOCondition condition,
219 unsigned char buf[128];
222 struct cmsghdr *cmsg;
228 if (condition & (G_IO_HUP | G_IO_ERR | G_IO_NVAL)) {
229 connman_error("Problem with timer server channel");
234 fd = g_io_channel_unix_get_fd(channel);
237 iov.iov_len = sizeof(buf);
239 memset(&msg, 0, sizeof(msg));
242 msg.msg_control = aux;
243 msg.msg_controllen = sizeof(aux);
245 len = recvmsg(fd, &msg, MSG_DONTWAIT);
251 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
252 if (cmsg->cmsg_level != SOL_SOCKET)
255 switch (cmsg->cmsg_type) {
257 tv = (struct timeval *) CMSG_DATA(cmsg);
262 decode_msg(iov.iov_base, iov.iov_len, tv);
267 static void start_ntp(char *server)
270 struct sockaddr_in addr;
271 int tos = IPTOS_LOWDELAY, timestamp = 1;
276 DBG("server %s", server);
278 if (channel_watch > 0)
281 transmit_fd = socket(PF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
282 if (transmit_fd < 0) {
283 connman_error("Failed to open time server socket");
287 memset(&addr, 0, sizeof(addr));
288 addr.sin_family = AF_INET;
290 if (bind(transmit_fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
291 connman_error("Failed to bind time server socket");
296 if (setsockopt(transmit_fd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0) {
297 connman_error("Failed to set type of service option");
302 if (setsockopt(transmit_fd, SOL_SOCKET, SO_TIMESTAMP, ×tamp,
303 sizeof(timestamp)) < 0) {
304 connman_error("Failed to enable timestamp support");
309 channel = g_io_channel_unix_new(transmit_fd);
310 if (channel == NULL) {
315 g_io_channel_set_encoding(channel, NULL, NULL);
316 g_io_channel_set_buffered(channel, FALSE);
318 g_io_channel_set_close_on_unref(channel, TRUE);
320 channel_watch = g_io_add_watch_full(channel, G_PRIORITY_DEFAULT,
321 G_IO_IN | G_IO_HUP | G_IO_ERR | G_IO_NVAL,
322 received_data, NULL, NULL);
324 g_io_channel_unref(channel);
327 send_packet(transmit_fd, server);
330 int __connman_ntp_start(char *server)
337 if (timeserver != NULL)
340 timeserver = g_strdup(server);
342 start_ntp(timeserver);
347 void __connman_ntp_stop()
352 g_source_remove(poll_id);
354 if (channel_watch > 0) {
355 g_source_remove(channel_watch);
360 if (timeserver != NULL) {