dll/cpl/timedate/ntpclient.c

   1 /*
   2  * PROJECT:     ReactOS Timedate Control Panel
   3  * LICENSE:     GPL - See COPYING in the top level directory
   4  * FILE:        dll/cpl/timedate/ntpclient.c
   5  * PURPOSE:     Queries the NTP server
   6  * COPYRIGHT:   Copyright 2006 Ged Murphy <gedmurphy@gmail.com>
   7  *
   8  */
   9
  10 #include "timedate.h"
  11
  12 #include <winsock2.h>
  13
  14 #define TIMEOUT 4000 /* 4 second timeout */
  15
  16 typedef struct _INFO
  17 {
  18     SOCKET Sock;
  19     SOCKADDR_IN myAddr;
  20     SOCKADDR_IN ntpAddr;
  21     NTPPACKET SendPacket;
  22     NTPPACKET RecvPacket;
  23 } INFO, *PINFO;
  24
  25
  26 static BOOL
  27 InitConnection(PINFO pInfo,
  28                LPSTR lpAddress)
  29 {
  30     WSADATA wsaData;
  31     HOSTENT *he;
  32     INT Ret;
  33
  34     Ret = WSAStartup(MAKEWORD(2, 2),
  35                      &wsaData);
  36     if (Ret != 0)
  37         return FALSE;
  38
  39     pInfo->Sock = socket(AF_INET,
  40                          SOCK_DGRAM,
  41                          0);
  42     if (pInfo->Sock == INVALID_SOCKET)
  43         return FALSE;
  44
  45     /* Setup server info */
  46     he = gethostbyname(lpAddress);
  47     if (he != NULL)
  48     {
  49         /* Setup server socket info */
  50         ZeroMemory(&pInfo->ntpAddr, sizeof(SOCKADDR_IN));
  51         pInfo->ntpAddr.sin_family = AF_INET; // he->h_addrtype;
  52         pInfo->ntpAddr.sin_port = htons(NTPPORT);
  53         pInfo->ntpAddr.sin_addr = *((struct in_addr *)he->h_addr);
  54     }
  55     else
  56         return FALSE;
  57
  58     return TRUE;
  59 }
  60
  61
  62 static VOID
  63 DestroyConnection(VOID)
  64 {
  65     WSACleanup();
  66 }
  67
  68
  69 static BOOL
  70 GetTransmitTime(PTIMEPACKET ptp)
  71 {
  72     return TRUE;
  73 }
  74
  75
  76 /* Send some data to wake the server up */
  77 static BOOL
  78 SendData(PINFO pInfo)
  79 {
  80     TIMEPACKET tp = { 0, 0 };
  81     INT Ret;
  82
  83     ZeroMemory(&pInfo->SendPacket, sizeof(pInfo->SendPacket));
  84     pInfo->SendPacket.LiVnMode = 27;
  85     if (!GetTransmitTime(&tp))
  86         return FALSE;
  87     pInfo->SendPacket.TransmitTimestamp = tp;
  88
  89     Ret = sendto(pInfo->Sock,
  90                  (char *)&pInfo->SendPacket,
  91                  sizeof(pInfo->SendPacket),
  92                  0,
  93                  (SOCKADDR *)&pInfo->ntpAddr,
  94                  sizeof(SOCKADDR_IN));
  95
  96     if (Ret == SOCKET_ERROR)
  97         return FALSE;
  98
  99     return TRUE;
 100 }
 101
 102
 103 static ULONG
 104 ReceiveData(PINFO pInfo)
 105 {
 106     TIMEVAL timeVal;
 107     FD_SET readFDS;
 108     INT Ret;
 109     ULONG ulTime = 0;
 110
 111     /* Monitor socket for incomming connections */
 112     FD_ZERO(&readFDS);
 113     FD_SET(pInfo->Sock, &readFDS);
 114
 115     /* Set timeout values */
 116     timeVal.tv_sec  = TIMEOUT / 1000;
 117     timeVal.tv_usec = TIMEOUT % 1000;
 118
 119     /* Check for data on the socket for TIMEOUT millisecs */
 120     Ret = select(0, &readFDS, NULL, NULL, &timeVal);
 121
 122     if ((Ret != SOCKET_ERROR) && (Ret != 0))
 123     {
 124
 125         Ret = recvfrom(pInfo->Sock,
 126                        (char *)&pInfo->RecvPacket,
 127                        sizeof(pInfo->RecvPacket),
 128                        0,
 129                        NULL,
 130                        NULL);
 131         if (Ret != SOCKET_ERROR)
 132             ulTime = ntohl(ulTime);
 133     }
 134
 135     return ulTime;
 136 }
 137
 138
 139 ULONG
 140 GetServerTime(LPWSTR lpAddress)
 141 {
 142     PINFO pInfo;
 143     LPSTR lpAddr;
 144     DWORD dwSize = wcslen(lpAddress) + 1;
 145     ULONG ulTime = 0;
 146
 147     pInfo = (PINFO)HeapAlloc(GetProcessHeap(),
 148                              0,
 149                              sizeof(INFO));
 150     lpAddr = (LPSTR)HeapAlloc(GetProcessHeap(),
 151                               0,
 152                               dwSize);
 153
 154     if (pInfo && lpAddr)
 155     {
 156         if (WideCharToMultiByte(CP_ACP,
 157                                 0,
 158                                 lpAddress,
 159                                 -1,
 160                                 lpAddr,
 161                                 dwSize,
 162                                 NULL,
 163                                 NULL))
 164         {
 165             if (InitConnection(pInfo, lpAddr))
 166             {
 167                 if (SendData(pInfo))
 168                 {
 169                     ulTime = ReceiveData(pInfo);
 170                 }
 171             }
 172
 173             DestroyConnection();
 174         }
 175     }
 176
 177     if (pInfo)
 178         HeapFree(GetProcessHeap(), 0, pInfo);
 179     if (lpAddr)
 180         HeapFree(GetProcessHeap(), 0, lpAddr);
 181
 182     return ulTime;
 183 }