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Counter
Dependencies: EthernetInterface NTPClient SDFileSystem TextLCD WebSocketClient mbed-rtos mbed Socket lwip-eth lwip-sys lwip FATFileSystem
Diff: NTPClient/NTPClient.cpp
- Revision:
- 0:ecaf3e593122
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/NTPClient/NTPClient.cpp Mon Feb 29 18:59:15 2016 +0000 @@ -0,0 +1,163 @@ +/* NTPClient.cpp */ +/* Copyright (C) 2012 mbed.org, MIT License + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software + * and associated documentation files (the "Software"), to deal in the Software without restriction, + * including without limitation the rights to use, copy, modify, merge, publish, distribute, + * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or + * substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING + * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +//Debug is disabled by default +#if 0 +//Enable debug +#define __DEBUG__ +#include <cstdio> +#define DBG(x, ...) std::printf("[NTPClient : DBG]"x"\r\n", ##__VA_ARGS__); +#define WARN(x, ...) std::printf("[NTPClient : WARN]"x"\r\n", ##__VA_ARGS__); +#define ERR(x, ...) std::printf("[NTPClient : ERR]"x"\r\n", ##__VA_ARGS__); + +#else +//Disable debug +#define DBG(x, ...) +#define WARN(x, ...) +#define ERR(x, ...) + +#endif + +#include "NTPClient.h" + +#include "UDPSocket.h" + +#include "mbed.h" //time() and set_time() + +#define NTP_PORT 123 +#define NTP_CLIENT_PORT 0 //Random port +#define NTP_TIMESTAMP_DELTA 2208988800ull //Diff btw a UNIX timestamp (Starting Jan, 1st 1970) and a NTP timestamp (Starting Jan, 1st 1900) + +NTPClient::NTPClient() : m_sock() +{ + + +} + +NTPResult NTPClient::setTime(const char* host, uint16_t port, uint32_t timeout) +{ +#ifdef __DEBUG__ + time_t ctTime; + ctTime = time(NULL); + DBG("Time is set to (UTC): %s", ctime(&ctTime)); +#endif + + //Create & bind socket + DBG("Binding socket"); + m_sock.bind(0); //Bind to a random port + + m_sock.set_blocking(false, timeout); //Set not blocking + + struct NTPPacket pkt; + + //Now ping the server and wait for response + DBG("Ping"); + //Prepare NTP Packet: + pkt.li = 0; //Leap Indicator : No warning + pkt.vn = 4; //Version Number : 4 + pkt.mode = 3; //Client mode + pkt.stratum = 0; //Not relevant here + pkt.poll = 0; //Not significant as well + pkt.precision = 0; //Neither this one is + + pkt.rootDelay = 0; //Or this one + pkt.rootDispersion = 0; //Or that one + pkt.refId = 0; //... + + pkt.refTm_s = 0; + pkt.origTm_s = 0; + pkt.rxTm_s = 0; + pkt.txTm_s = htonl( NTP_TIMESTAMP_DELTA + time(NULL) ); //WARN: We are in LE format, network byte order is BE + + pkt.refTm_f = pkt.origTm_f = pkt.rxTm_f = pkt.txTm_f = 0; + + Endpoint outEndpoint; + + if( outEndpoint.set_address(host, port) < 0) + { + m_sock.close(); + return NTP_DNS; + } + + //Set timeout, non-blocking and wait using select + int ret = m_sock.sendTo( outEndpoint, (char*)&pkt, sizeof(NTPPacket) ); + if (ret < 0 ) + { + ERR("Could not send packet"); + m_sock.close(); + return NTP_CONN; + } + + //Read response + Endpoint inEndpoint; + + DBG("Pong"); + do + { + ret = m_sock.receiveFrom( inEndpoint, (char*)&pkt, sizeof(NTPPacket) ); //FIXME need a DNS Resolver to actually compare the incoming address with the DNS name + if(ret < 0) + { + ERR("Could not receive packet"); + m_sock.close(); + return NTP_CONN; + } + } while( strcmp(outEndpoint.get_address(), inEndpoint.get_address()) != 0 ); + + if(ret < sizeof(NTPPacket)) //TODO: Accept chunks + { + ERR("Receive packet size does not match"); + m_sock.close(); + return NTP_PRTCL; + } + + if( pkt.stratum == 0) //Kiss of death message : Not good ! + { + ERR("Kissed to death!"); + m_sock.close(); + return NTP_PRTCL; + } + + //Correct Endianness + pkt.refTm_s = ntohl( pkt.refTm_s ); + pkt.refTm_f = ntohl( pkt.refTm_f ); + pkt.origTm_s = ntohl( pkt.origTm_s ); + pkt.origTm_f = ntohl( pkt.origTm_f ); + pkt.rxTm_s = ntohl( pkt.rxTm_s ); + pkt.rxTm_f = ntohl( pkt.rxTm_f ); + pkt.txTm_s = ntohl( pkt.txTm_s ); + pkt.txTm_f = ntohl( pkt.txTm_f ); + + //Compute offset, see RFC 4330 p.13 + uint32_t destTm_s = (NTP_TIMESTAMP_DELTA + time(NULL)); + int64_t offset = ( (int64_t)( pkt.rxTm_s - pkt.origTm_s ) + (int64_t) ( pkt.txTm_s - destTm_s ) ) / 2; //Avoid overflow + DBG("Sent @%ul", pkt.txTm_s); + DBG("Offset: %lld", offset); + //Set time accordingly + set_time( time(NULL) + offset ); + +#ifdef __DEBUG__ + ctTime = time(NULL); + DBG("Time is now (UTC): %s", ctime(&ctTime)); +#endif + + m_sock.close(); + + return NTP_OK; +} +