diff options
Diffstat (limited to 'lib/rtems_bsdnet_ntp.c')
| -rw-r--r-- | lib/rtems_bsdnet_ntp.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/lib/rtems_bsdnet_ntp.c b/lib/rtems_bsdnet_ntp.c new file mode 100644 index 0000000..e675759 --- /dev/null +++ b/lib/rtems_bsdnet_ntp.c @@ -0,0 +1,219 @@ +#include <machine/rtems-bsd-user-space.h> + +/* + * Synchronize with an NTP server + * + * This program may be distributed and used for any purpose. + * I ask only that you: + * 1. Leave this author information intact. + * 2. Document any changes you make. + * + * W. Eric Norum + * Canadian Light Source + * University of Saskatchewan + * Saskatoon, Saskatchewan, CANADA + * eric@cls.usask.ca + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <unistd.h> /* close */ +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <time.h> +#include <limits.h> +#include <rtems.h> +#include <rtems/rtems_bsdnet.h> +#include <rtems/error.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> + +#include <rtems/bsdnet/servers.h> + +/* + * RTEMS base: 1988, January 1 + * UNIX base: 1970, January 1 + * NTP base: 1900, January 1 + */ +#define UNIX_BASE_TO_NTP_BASE (uint32_t)(((70UL*365UL)+17UL) * (24UL*60UL*60UL)) + +struct ntpPacket { + struct ntpPacketSmall ntp; + char authenticator[96]; +}; + +static int +processPacket (struct ntpPacketSmall *p, int state, void *unused) +{ + time_t tbuf; + struct tm *lt; + rtems_time_of_day rt; + rtems_interval ticks_per_second; + + if ( state ) + return 0; + + ticks_per_second = rtems_clock_get_ticks_per_second(); + tbuf = ntohl (p->transmit_timestamp.integer) - UNIX_BASE_TO_NTP_BASE - rtems_bsdnet_timeoffset; + lt = gmtime (&tbuf); + rt.year = lt->tm_year + 1900; + rt.month = lt->tm_mon + 1; + rt.day = lt->tm_mday; + rt.hour = lt->tm_hour; + rt.minute = lt->tm_min; + rt.second = lt->tm_sec; + rt.ticks = ntohl (p->transmit_timestamp.fraction) / (ULONG_MAX / ticks_per_second); + if (rt.ticks >= ticks_per_second) + rt.ticks = ticks_per_second - 1; + rtems_clock_set (&rt); + return 0; +} + +static int +getServerTimespec(struct ntpPacketSmall *p, int state, void *usr_data) +{ +struct timespec *ts = usr_data; +unsigned long long tmp; + + if ( 0 == state ) { + ts->tv_sec = ntohl( p->transmit_timestamp.integer ); + ts->tv_sec -= rtems_bsdnet_timeoffset + UNIX_BASE_TO_NTP_BASE; + + tmp = 1000000000 * (unsigned long long)ntohl(p->transmit_timestamp.fraction); + + ts->tv_nsec = (unsigned long) (tmp>>32); + } + return 0; +} + +int rtems_bsdnet_ntp_retry_count = 5; +int rtems_bsdnet_ntp_timeout_secs = 5; +int rtems_bsdnet_ntp_bcast_timeout_secs = 80; + +static int +tryServer (int i, int s, rtems_bsdnet_ntp_callback_t callback, void *usr_data) +{ + int l = 0; + struct timeval tv; + socklen_t farlen; + struct sockaddr_in farAddr; + struct ntpPacketSmall packet; + + if (i < 0) + tv.tv_sec = rtems_bsdnet_ntp_bcast_timeout_secs; + else + tv.tv_sec = rtems_bsdnet_ntp_timeout_secs; + tv.tv_usec = 0; + if (setsockopt (s, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv, sizeof tv) < 0) { + fprintf (stderr, "rtems_bsdnet_get_ntp() Can't set socket receive timeout: %s\n", strerror (errno)); + close (s); + return -1; + } + if (i >= 0) { + memset (&farAddr, 0, sizeof farAddr); + farAddr.sin_family = AF_INET; + farAddr.sin_port = htons (123); + farAddr.sin_addr = rtems_bsdnet_ntpserver[i]; + memset (&packet, 0, sizeof packet); + packet.li_vn_mode = (3 << 3) | 3; /* NTP version 3, client */ + if ( callback( &packet, 1, usr_data ) ) + return -1; + l = sendto (s, &packet, sizeof packet, 0, (struct sockaddr *)&farAddr, sizeof farAddr); + if (l != sizeof packet) { + fprintf (stderr, "rtems_bsdnet_get_ntp() Can't send: %s\n", strerror (errno)); + return -1; + } + } else { + if ( callback( &packet, -1, usr_data ) ) + return -1; + } + farlen = sizeof farAddr; + i = recvfrom (s, &packet, sizeof packet, 0, (struct sockaddr *)&farAddr, &farlen); + if (i == 0) + fprintf (stderr, "rtems_bsdnet_get_ntp() Unexpected EOF"); + if (i < 0) { + if ((errno == EWOULDBLOCK) || (errno == EAGAIN)) + return -1; + fprintf (stderr, "rtems_bsdnet_get_ntp() Can't receive: %s\n", strerror (errno)); + } + + if ( i >= sizeof packet && + (((packet.li_vn_mode & (0x7 << 3)) == (3 << 3)) || + ((packet.li_vn_mode & (0x7 << 3)) == (4 << 3))) && + ((packet.transmit_timestamp.integer != 0) || (packet.transmit_timestamp.fraction != 0)) && + 0 == callback( &packet, 0 , usr_data) ) + return 0; + + return -1; +} + +int rtems_bsdnet_get_ntp(int sock, rtems_bsdnet_ntp_callback_t callback, void *usr_data) +{ +int s = -1; +int i; +int retry; +struct sockaddr_in myAddr; +int reuseFlag; +int ret; + + if ( !callback ) + callback = getServerTimespec; + + if ( sock < 0 ) { + s = socket (AF_INET, SOCK_DGRAM, 0); + if (s < 0) { + fprintf (stderr, "rtems_bsdnet_get_ntp() Can't create socket: %s\n", strerror (errno)); + return -1; + } + reuseFlag = 1; + if (setsockopt (s, SOL_SOCKET, SO_REUSEADDR, (char *)&reuseFlag, sizeof reuseFlag) < 0) { + fprintf (stderr, "rtems_bsdnet_get_ntp() Can't set socket reuse: %s\n", strerror (errno)); + close (s); + return -1; + } + memset (&myAddr, 0, sizeof myAddr); + myAddr.sin_family = AF_INET; + myAddr.sin_port = htons (123); + myAddr.sin_addr.s_addr = htonl (INADDR_ANY); + if (bind (s, (struct sockaddr *)&myAddr, sizeof myAddr) < 0) { + fprintf (stderr, "rtems_bsdnet_get_ntp() Can't bind socket: %s\n", strerror (errno)); + close (s); + return -1; + } + sock = s; + } + ret = -1; + for (retry = 0 ; (ret == -1) && (retry < rtems_bsdnet_ntp_retry_count) ; retry++) { + /* + * If there's no server we just have to wait + * and hope that there's an NTP broadcast + * server out there somewhere. + */ + if (rtems_bsdnet_ntpserver_count <= 0) { + ret = tryServer (-1, sock, callback, usr_data); + } + else { + for (i = 0 ; (ret == -1) && (i < rtems_bsdnet_ntpserver_count) ; i++) { + ret = tryServer (i, sock, callback, usr_data); + } + } + } + if ( s >= 0 ) + close (s); + return ret; +} + +int +rtems_bsdnet_synchronize_ntp (int interval, rtems_task_priority priority) +{ + if (interval != 0) { + fprintf (stderr, "Daemon-mode note yet supported.\n"); + errno = EINVAL; + return -1; + } + return rtems_bsdnet_get_ntp( -1, processPacket, 0); +} |