/** * @file * SNTP client module * */ /* * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY * OF SUCH DAMAGE. * * This file is part of the lwIP TCP/IP stack. * */ #include "lwip/opt.h" #if LWIP_SOCKET /* don't build if not configured for use in lwipopts.h */ #include "lwip/sys.h" #include "lwip/sockets.h" #include "time.h" /** This is an example of a "SNTP" client (with socket API). * * For a list of some public NTP servers, see this link : * http://support.ntp.org/bin/view/Servers/NTPPoolServers * */ /** * SNTP_DEBUG: Enable debugging for SNTP. */ #ifndef SNTP_DEBUG #define SNTP_DEBUG LWIP_DBG_ON #endif /** SNTP server port */ #ifndef SNTP_PORT #define SNTP_PORT 123 #endif /** SNTP server address as IPv4 address in "u32_t" format */ #ifndef SNTP_SERVER_ADDRESS #define SNTP_SERVER_ADDRESS inet_addr("91.121.71.87") /* pool.ntp.org */ #endif /** SNTP receive timeout - in milliseconds */ #ifndef SNTP_RECV_TIMEOUT #define SNTP_RECV_TIMEOUT 3000 #endif /** SNTP update delay - in milliseconds */ #ifndef SNTP_UPDATE_DELAY #define SNTP_UPDATE_DELAY 60000 #endif /** SNTP macro to change system time and/or the update the RTC clock */ #ifndef SNTP_SYSTEM_TIME #define SNTP_SYSTEM_TIME(t) #endif /* SNTP protocol defines */ #define SNTP_MAX_DATA_LEN 48 #define SNTP_RCV_TIME_OFS 32 #define SNTP_LI_NO_WARNING 0x00 #define SNTP_VERSION (4/* NTP Version 4*/<<3) #define SNTP_MODE_CLIENT 0x03 #define SNTP_MODE_SERVER 0x04 #define SNTP_MODE_BROADCAST 0x05 #define SNTP_MODE_MASK 0x07 /* number of seconds between 1900 and 1970 */ #define DIFF_SEC_1900_1970 (2208988800) /** * SNTP processing */ static void sntp_process( time_t t) { /* change system time and/or the update the RTC clock */ SNTP_SYSTEM_TIME(t); /* display local time from GMT time */ LWIP_DEBUGF( SNTP_DEBUG, ("sntp_process: %s", ctime(&t))); } /** * SNTP request */ static void sntp_request() { int sock; struct sockaddr_in local; struct sockaddr_in to; int tolen; int size; int timeout; u8_t sntp_request [SNTP_MAX_DATA_LEN]; u8_t sntp_response[SNTP_MAX_DATA_LEN]; u32_t sntp_server_address; u32_t timestamp; time_t t; /* initialize SNTP server address */ sntp_server_address = SNTP_SERVER_ADDRESS; /* if we got a valid SNTP server address... */ if (sntp_server_address!=0) { /* create new socket */ sock = socket( AF_INET, SOCK_DGRAM, 0); if (sock>=0) { /* prepare local address */ memset(&local, 0, sizeof(local)); local.sin_family = AF_INET; local.sin_port = htons(INADDR_ANY); local.sin_addr.s_addr = htonl(INADDR_ANY); /* bind to local address */ if (bind( sock, (struct sockaddr *)&local, sizeof(local))==0) { /* set recv timeout */ timeout = SNTP_RECV_TIMEOUT; setsockopt( sock, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout)); /* prepare SNTP request */ memset( sntp_request, 0, sizeof(sntp_request)); sntp_request[0] = SNTP_LI_NO_WARNING | SNTP_VERSION | SNTP_MODE_CLIENT; /* prepare SNTP server address */ memset(&to, 0, sizeof(to)); to.sin_family = AF_INET; to.sin_port = htons(SNTP_PORT); to.sin_addr.s_addr = sntp_server_address; /* send SNTP request to server */ if (sendto( sock, sntp_request, sizeof(sntp_request), 0, (struct sockaddr *)&to, sizeof(to))>=0) { /* receive SNTP server response */ tolen = sizeof(to); size = recvfrom( sock, sntp_response, sizeof(sntp_response), 0, (struct sockaddr *)&to, (socklen_t *)&tolen); /* if the response size is good */ if (size == SNTP_MAX_DATA_LEN) { /* if this is a SNTP response... */ if (((sntp_response[0] & SNTP_MODE_MASK) == SNTP_MODE_SERVER) || ((sntp_response[0] & SNTP_MODE_MASK) == SNTP_MODE_BROADCAST)) { /* extract GMT time from response */ SMEMCPY( ×tamp, (sntp_response+SNTP_RCV_TIME_OFS), sizeof(timestamp)); t = (ntohl(timestamp) - DIFF_SEC_1900_1970); /* do time processing */ sntp_process(t); } else { LWIP_DEBUGF( SNTP_DEBUG, ("sntp_request: not response frame code\n")); } } else { LWIP_DEBUGF( SNTP_DEBUG, ("sntp_request: not recvfrom==%i\n", errno)); } } else { LWIP_DEBUGF( SNTP_DEBUG, ("sntp_request: not sendto==%i\n", errno)); } } /* close the socket */ closesocket(sock); } } } /** * SNTP thread */ static void sntp_thread(void *arg) { while(1) { sntp_request(); sys_msleep(SNTP_UPDATE_DELAY); } } void sntp_init(void) { sys_thread_new("sntp_thread", sntp_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO); } #endif /* LWIP_SOCKET */