Albin Sebastian / WIZnetInterface

Library for ethernet

Dependents:   VC0706_FTP_Client_Ethernet_MQTT

Fork of WIZnetInterface by Akshay Tom

Socket/NTPClient.cpp@16:c830d2e7e0f5, 2015-06-24 (annotated)

Committer:
eunkyoungkim
Date:
Wed Jun 24 02:27:46 2015 +0000
Revision:
16:c830d2e7e0f5
Add SNTP Client

Who changed what in which revision?

UserRevisionLine numberNew contents of line
eunkyoungkim 16:c830d2e7e0f5 1 /* NTPClient.cpp */
eunkyoungkim 16:c830d2e7e0f5 2 /* Copyright (C) 2012 mbed.org, MIT License
eunkyoungkim 16:c830d2e7e0f5 3 *
eunkyoungkim 16:c830d2e7e0f5 4 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
eunkyoungkim 16:c830d2e7e0f5 5 * and associated documentation files (the "Software"), to deal in the Software without restriction,
eunkyoungkim 16:c830d2e7e0f5 6 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
eunkyoungkim 16:c830d2e7e0f5 7 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
eunkyoungkim 16:c830d2e7e0f5 8 * furnished to do so, subject to the following conditions:
eunkyoungkim 16:c830d2e7e0f5 9 *
eunkyoungkim 16:c830d2e7e0f5 10 * The above copyright notice and this permission notice shall be included in all copies or
eunkyoungkim 16:c830d2e7e0f5 11 * substantial portions of the Software.
eunkyoungkim 16:c830d2e7e0f5 12 *
eunkyoungkim 16:c830d2e7e0f5 13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
eunkyoungkim 16:c830d2e7e0f5 14 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
eunkyoungkim 16:c830d2e7e0f5 15 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
eunkyoungkim 16:c830d2e7e0f5 16 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
eunkyoungkim 16:c830d2e7e0f5 17 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
eunkyoungkim 16:c830d2e7e0f5 18 */
eunkyoungkim 16:c830d2e7e0f5 19
eunkyoungkim 16:c830d2e7e0f5 20 //Debug is disabled by default
eunkyoungkim 16:c830d2e7e0f5 21 #if 0
eunkyoungkim 16:c830d2e7e0f5 22 //Enable debug
eunkyoungkim 16:c830d2e7e0f5 23 #define __DEBUG__
eunkyoungkim 16:c830d2e7e0f5 24 #include <cstdio>
eunkyoungkim 16:c830d2e7e0f5 25 #define DBG(x, ...) std::printf("[NTPClient : DBG]"x"\r\n", ##__VA_ARGS__);
eunkyoungkim 16:c830d2e7e0f5 26 #define WARN(x, ...) std::printf("[NTPClient : WARN]"x"\r\n", ##__VA_ARGS__);
eunkyoungkim 16:c830d2e7e0f5 27 #define ERR(x, ...) std::printf("[NTPClient : ERR]"x"\r\n", ##__VA_ARGS__);
eunkyoungkim 16:c830d2e7e0f5 28
eunkyoungkim 16:c830d2e7e0f5 29 #else
eunkyoungkim 16:c830d2e7e0f5 30 //Disable debug
eunkyoungkim 16:c830d2e7e0f5 31 #define DBG(x, ...)
eunkyoungkim 16:c830d2e7e0f5 32 #define WARN(x, ...)
eunkyoungkim 16:c830d2e7e0f5 33 #define ERR(x, ...)
eunkyoungkim 16:c830d2e7e0f5 34
eunkyoungkim 16:c830d2e7e0f5 35 #endif
eunkyoungkim 16:c830d2e7e0f5 36
eunkyoungkim 16:c830d2e7e0f5 37 #include "NTPClient.h"
eunkyoungkim 16:c830d2e7e0f5 38
eunkyoungkim 16:c830d2e7e0f5 39 #include "UDPSocket.h"
eunkyoungkim 16:c830d2e7e0f5 40
eunkyoungkim 16:c830d2e7e0f5 41 #include "mbed.h" //time() and set_time()
eunkyoungkim 16:c830d2e7e0f5 42
eunkyoungkim 16:c830d2e7e0f5 43 #define NTP_PORT 123
eunkyoungkim 16:c830d2e7e0f5 44 #define NTP_CLIENT_PORT 0 //Random port
eunkyoungkim 16:c830d2e7e0f5 45 #define NTP_TIMESTAMP_DELTA 2208988800ull //Diff btw a UNIX timestamp (Starting Jan, 1st 1970) and a NTP timestamp (Starting Jan, 1st 1900)
eunkyoungkim 16:c830d2e7e0f5 46
eunkyoungkim 16:c830d2e7e0f5 47 NTPClient::NTPClient() : m_sock()
eunkyoungkim 16:c830d2e7e0f5 48 {
eunkyoungkim 16:c830d2e7e0f5 49
eunkyoungkim 16:c830d2e7e0f5 50
eunkyoungkim 16:c830d2e7e0f5 51 }
eunkyoungkim 16:c830d2e7e0f5 52
eunkyoungkim 16:c830d2e7e0f5 53 NTPResult NTPClient::setTime(const char* host, uint16_t port, uint32_t timeout)
eunkyoungkim 16:c830d2e7e0f5 54 {
eunkyoungkim 16:c830d2e7e0f5 55 #ifdef __DEBUG__
eunkyoungkim 16:c830d2e7e0f5 56 time_t ctTime;
eunkyoungkim 16:c830d2e7e0f5 57 ctTime = time(NULL);
eunkyoungkim 16:c830d2e7e0f5 58 DBG("Time is set to (UTC): %s", ctime(&ctTime));
eunkyoungkim 16:c830d2e7e0f5 59 #endif
eunkyoungkim 16:c830d2e7e0f5 60
eunkyoungkim 16:c830d2e7e0f5 61 //Create & bind socket
eunkyoungkim 16:c830d2e7e0f5 62 DBG("Binding socket");
eunkyoungkim 16:c830d2e7e0f5 63 m_sock.bind(0); //Bind to a random port
eunkyoungkim 16:c830d2e7e0f5 64
eunkyoungkim 16:c830d2e7e0f5 65 m_sock.set_blocking(false, timeout); //Set not blocking
eunkyoungkim 16:c830d2e7e0f5 66
eunkyoungkim 16:c830d2e7e0f5 67 struct NTPPacket pkt;
eunkyoungkim 16:c830d2e7e0f5 68
eunkyoungkim 16:c830d2e7e0f5 69 //Now ping the server and wait for response
eunkyoungkim 16:c830d2e7e0f5 70 DBG("Ping");
eunkyoungkim 16:c830d2e7e0f5 71 //Prepare NTP Packet:
eunkyoungkim 16:c830d2e7e0f5 72 pkt.li = 0; //Leap Indicator : No warning
eunkyoungkim 16:c830d2e7e0f5 73 pkt.vn = 4; //Version Number : 4
eunkyoungkim 16:c830d2e7e0f5 74 pkt.mode = 3; //Client mode
eunkyoungkim 16:c830d2e7e0f5 75 pkt.stratum = 0; //Not relevant here
eunkyoungkim 16:c830d2e7e0f5 76 pkt.poll = 0; //Not significant as well
eunkyoungkim 16:c830d2e7e0f5 77 pkt.precision = 0; //Neither this one is
eunkyoungkim 16:c830d2e7e0f5 78
eunkyoungkim 16:c830d2e7e0f5 79 pkt.rootDelay = 0; //Or this one
eunkyoungkim 16:c830d2e7e0f5 80 pkt.rootDispersion = 0; //Or that one
eunkyoungkim 16:c830d2e7e0f5 81 pkt.refId = 0; //...
eunkyoungkim 16:c830d2e7e0f5 82
eunkyoungkim 16:c830d2e7e0f5 83 pkt.refTm_s = 0;
eunkyoungkim 16:c830d2e7e0f5 84 pkt.origTm_s = 0;
eunkyoungkim 16:c830d2e7e0f5 85 pkt.rxTm_s = 0;
eunkyoungkim 16:c830d2e7e0f5 86 pkt.txTm_s = htonl( NTP_TIMESTAMP_DELTA + time(NULL) ); //WARN: We are in LE format, network byte order is BE
eunkyoungkim 16:c830d2e7e0f5 87
eunkyoungkim 16:c830d2e7e0f5 88 pkt.refTm_f = pkt.origTm_f = pkt.rxTm_f = pkt.txTm_f = 0;
eunkyoungkim 16:c830d2e7e0f5 89
eunkyoungkim 16:c830d2e7e0f5 90 Endpoint outEndpoint;
eunkyoungkim 16:c830d2e7e0f5 91
eunkyoungkim 16:c830d2e7e0f5 92 if( outEndpoint.set_address(host, port) < 0)
eunkyoungkim 16:c830d2e7e0f5 93 {
eunkyoungkim 16:c830d2e7e0f5 94 m_sock.close();
eunkyoungkim 16:c830d2e7e0f5 95 return NTP_DNS;
eunkyoungkim 16:c830d2e7e0f5 96 }
eunkyoungkim 16:c830d2e7e0f5 97
eunkyoungkim 16:c830d2e7e0f5 98 //Set timeout, non-blocking and wait using select
eunkyoungkim 16:c830d2e7e0f5 99 int ret = m_sock.sendTo( outEndpoint, (char*)&pkt, sizeof(NTPPacket) );
eunkyoungkim 16:c830d2e7e0f5 100 if (ret < 0 )
eunkyoungkim 16:c830d2e7e0f5 101 {
eunkyoungkim 16:c830d2e7e0f5 102 ERR("Could not send packet");
eunkyoungkim 16:c830d2e7e0f5 103 m_sock.close();
eunkyoungkim 16:c830d2e7e0f5 104 return NTP_CONN;
eunkyoungkim 16:c830d2e7e0f5 105 }
eunkyoungkim 16:c830d2e7e0f5 106
eunkyoungkim 16:c830d2e7e0f5 107 //Read response
eunkyoungkim 16:c830d2e7e0f5 108 Endpoint inEndpoint;
eunkyoungkim 16:c830d2e7e0f5 109
eunkyoungkim 16:c830d2e7e0f5 110 DBG("Pong");
eunkyoungkim 16:c830d2e7e0f5 111 do
eunkyoungkim 16:c830d2e7e0f5 112 {
eunkyoungkim 16:c830d2e7e0f5 113 ret = m_sock.receiveFrom( inEndpoint, (char*)&pkt, sizeof(NTPPacket) ); //FIXME need a DNS Resolver to actually compare the incoming address with the DNS name
eunkyoungkim 16:c830d2e7e0f5 114 if(ret < 0)
eunkyoungkim 16:c830d2e7e0f5 115 {
eunkyoungkim 16:c830d2e7e0f5 116 ERR("Could not receive packet");
eunkyoungkim 16:c830d2e7e0f5 117 m_sock.close();
eunkyoungkim 16:c830d2e7e0f5 118 return NTP_CONN;
eunkyoungkim 16:c830d2e7e0f5 119 }
eunkyoungkim 16:c830d2e7e0f5 120 } while( strcmp(outEndpoint.get_address(), inEndpoint.get_address()) != 0 );
eunkyoungkim 16:c830d2e7e0f5 121
eunkyoungkim 16:c830d2e7e0f5 122 if(ret < sizeof(NTPPacket)) //TODO: Accept chunks
eunkyoungkim 16:c830d2e7e0f5 123 {
eunkyoungkim 16:c830d2e7e0f5 124 ERR("Receive packet size does not match");
eunkyoungkim 16:c830d2e7e0f5 125 m_sock.close();
eunkyoungkim 16:c830d2e7e0f5 126 return NTP_PRTCL;
eunkyoungkim 16:c830d2e7e0f5 127 }
eunkyoungkim 16:c830d2e7e0f5 128
eunkyoungkim 16:c830d2e7e0f5 129 if( pkt.stratum == 0) //Kiss of death message : Not good !
eunkyoungkim 16:c830d2e7e0f5 130 {
eunkyoungkim 16:c830d2e7e0f5 131 ERR("Kissed to death!");
eunkyoungkim 16:c830d2e7e0f5 132 m_sock.close();
eunkyoungkim 16:c830d2e7e0f5 133 return NTP_PRTCL;
eunkyoungkim 16:c830d2e7e0f5 134 }
eunkyoungkim 16:c830d2e7e0f5 135
eunkyoungkim 16:c830d2e7e0f5 136 //Correct Endianness
eunkyoungkim 16:c830d2e7e0f5 137 pkt.refTm_s = ntohl( pkt.refTm_s );
eunkyoungkim 16:c830d2e7e0f5 138 pkt.refTm_f = ntohl( pkt.refTm_f );
eunkyoungkim 16:c830d2e7e0f5 139 pkt.origTm_s = ntohl( pkt.origTm_s );
eunkyoungkim 16:c830d2e7e0f5 140 pkt.origTm_f = ntohl( pkt.origTm_f );
eunkyoungkim 16:c830d2e7e0f5 141 pkt.rxTm_s = ntohl( pkt.rxTm_s );
eunkyoungkim 16:c830d2e7e0f5 142 pkt.rxTm_f = ntohl( pkt.rxTm_f );
eunkyoungkim 16:c830d2e7e0f5 143 pkt.txTm_s = ntohl( pkt.txTm_s );
eunkyoungkim 16:c830d2e7e0f5 144 pkt.txTm_f = ntohl( pkt.txTm_f );
eunkyoungkim 16:c830d2e7e0f5 145
eunkyoungkim 16:c830d2e7e0f5 146 //Compute offset, see RFC 4330 p.13
eunkyoungkim 16:c830d2e7e0f5 147 uint32_t destTm_s = (NTP_TIMESTAMP_DELTA + time(NULL));
eunkyoungkim 16:c830d2e7e0f5 148 int64_t offset = ( (int64_t)( pkt.rxTm_s - pkt.origTm_s ) + (int64_t) ( pkt.txTm_s - destTm_s ) ) / 2; //Avoid overflow
eunkyoungkim 16:c830d2e7e0f5 149 DBG("Sent @%ul", pkt.txTm_s);
eunkyoungkim 16:c830d2e7e0f5 150 DBG("Offset: %lld", offset);
eunkyoungkim 16:c830d2e7e0f5 151 //Set time accordingly
eunkyoungkim 16:c830d2e7e0f5 152 set_time( time(NULL) + offset );
eunkyoungkim 16:c830d2e7e0f5 153
eunkyoungkim 16:c830d2e7e0f5 154 #ifdef __DEBUG__
eunkyoungkim 16:c830d2e7e0f5 155 ctTime = time(NULL);
eunkyoungkim 16:c830d2e7e0f5 156 DBG("Time is now (UTC): %s", ctime(&ctTime));
eunkyoungkim 16:c830d2e7e0f5 157 #endif
eunkyoungkim 16:c830d2e7e0f5 158
eunkyoungkim 16:c830d2e7e0f5 159 m_sock.close();
eunkyoungkim 16:c830d2e7e0f5 160
eunkyoungkim 16:c830d2e7e0f5 161 return NTP_OK;
eunkyoungkim 16:c830d2e7e0f5 162 }
eunkyoungkim 16:c830d2e7e0f5 163