| /*************************************************************************** |
| * _ _ ____ _ |
| * Project ___| | | | _ \| | |
| * / __| | | | |_) | | |
| * | (__| |_| | _ <| |___ |
| * \___|\___/|_| \_\_____| |
| * |
| * Copyright (C) 1998 - 2022, Daniel Stenberg, <daniel@haxx.se>, et al. |
| * |
| * This software is licensed as described in the file COPYING, which |
| * you should have received as part of this distribution. The terms |
| * are also available at https://curl.se/docs/copyright.html. |
| * |
| * You may opt to use, copy, modify, merge, publish, distribute and/or sell |
| * copies of the Software, and permit persons to whom the Software is |
| * furnished to do so, under the terms of the COPYING file. |
| * |
| * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY |
| * KIND, either express or implied. |
| * |
| * SPDX-License-Identifier: curl |
| * |
| ***************************************************************************/ |
| /* <DESC> |
| * Set your system time from a remote HTTP server's Date: header. |
| * </DESC> |
| */ |
| /* This example code only builds as-is on Windows. |
| * |
| * While Unix/Linux user, you do not need this software. |
| * You can achieve the same result as synctime using curl, awk and date. |
| * Set proxy as according to your network, but beware of proxy Cache-Control. |
| * |
| * To set your system clock, root access is required. |
| * # date -s "`curl -sI https://nist.time.gov/timezone.cgi?UTC/s/0 \ |
| * | awk -F': ' '/Date: / {print $2}'`" |
| * |
| * To view remote webserver date and time. |
| * $ curl -sI https://nist.time.gov/timezone.cgi?UTC/s/0 \ |
| * | awk -F': ' '/Date: / {print $2}' |
| * |
| * Synchronising your computer clock via Internet time server usually relies |
| * on DAYTIME, TIME, or NTP protocols. These protocols provide good accurate |
| * time synchronization but it does not work very well through a |
| * firewall/proxy. Some adjustment has to be made to the firewall/proxy for |
| * these protocols to work properly. |
| * |
| * There is an indirect method. Since most webserver provide server time in |
| * their HTTP header, therefore you could synchronise your computer clock |
| * using HTTP protocol which has no problem with firewall/proxy. |
| * |
| * For this software to work, you should take note of these items. |
| * 1. Your firewall/proxy must allow your computer to surf internet. |
| * 2. Webserver system time must in sync with the NTP time server, |
| * or at least provide an accurate time keeping. |
| * 3. Webserver HTTP header does not provide the milliseconds units, |
| * so there is no way to get very accurate time. |
| * 4. This software could only provide an accuracy of +- a few seconds, |
| * as Round-Trip delay time is not taken into consideration. |
| * Compensation of network, firewall/proxy delay cannot be simply divide |
| * the Round-Trip delay time by half. |
| * 5. Win32 SetSystemTime() API will set your computer clock according to |
| * GMT/UTC time. Therefore your computer timezone must be properly set. |
| * 6. Webserver data should not be cached by the proxy server. Some |
| * webserver provide Cache-Control to prevent caching. |
| * |
| * References: |
| * https://web.archive.org/web/20100228012139/ \ |
| * tf.nist.gov/timefreq/service/its.htm |
| * https://web.archive.org/web/20100409024302/ \ |
| * tf.nist.gov/timefreq/service/firewall.htm |
| * |
| * Usage: |
| * This software will synchronise your computer clock only when you issue |
| * it with --synctime. By default, it only display the webserver's clock. |
| * |
| * Written by: Frank (contributed to libcurl) |
| * |
| * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, |
| * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY |
| * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. |
| * |
| * IN NO EVENT SHALL THE AUTHOR OF THIS SOFTWARE BE LIABLE FOR |
| * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, |
| * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, |
| * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF |
| * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE |
| * OF THIS SOFTWARE. |
| * |
| */ |
| |
| #include <stdio.h> |
| #include <time.h> |
| #ifndef __CYGWIN__ |
| #include <winsock2.h> |
| #include <windows.h> |
| #endif |
| #include <curl/curl.h> |
| |
| |
| #define MAX_STRING 256 |
| #define MAX_STRING1 MAX_STRING + 1 |
| |
| #define SYNCTIME_UA "synctime/1.0" |
| |
| typedef struct |
| { |
| char http_proxy[MAX_STRING1]; |
| char proxy_user[MAX_STRING1]; |
| char timeserver[MAX_STRING1]; |
| } conf_t; |
| |
| const char DefaultTimeServer[3][MAX_STRING1] = |
| { |
| "https://nist.time.gov/", |
| "https://www.google.com/" |
| }; |
| |
| const char *DayStr[] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"}; |
| const char *MthStr[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", |
| "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"}; |
| |
| int ShowAllHeader; |
| int AutoSyncTime; |
| SYSTEMTIME SYSTime; |
| SYSTEMTIME LOCALTime; |
| |
| #define HTTP_COMMAND_HEAD 0 |
| #define HTTP_COMMAND_GET 1 |
| |
| |
| size_t SyncTime_CURL_WriteOutput(void *ptr, size_t size, size_t nmemb, |
| void *stream) |
| { |
| fwrite(ptr, size, nmemb, stream); |
| return (nmemb*size); |
| } |
| |
| size_t SyncTime_CURL_WriteHeader(void *ptr, size_t size, size_t nmemb, |
| void *stream) |
| { |
| char TmpStr1[26], TmpStr2[26]; |
| |
| (void)stream; |
| |
| if(ShowAllHeader == 1) |
| fprintf(stderr, "%s", (char *)(ptr)); |
| |
| if(strncmp((char *)(ptr), "Date:", 5) == 0) { |
| if(ShowAllHeader == 0) |
| fprintf(stderr, "HTTP Server. %s", (char *)(ptr)); |
| |
| if(AutoSyncTime == 1) { |
| *TmpStr1 = 0; |
| *TmpStr2 = 0; |
| if(strlen((char *)(ptr)) > 50) /* Can prevent buffer overflow to |
| TmpStr1 & 2? */ |
| AutoSyncTime = 0; |
| else { |
| int RetVal = sscanf((char *)(ptr), "Date: %25s %hu %s %hu %hu:%hu:%hu", |
| TmpStr1, &SYSTime.wDay, TmpStr2, &SYSTime.wYear, |
| &SYSTime.wHour, &SYSTime.wMinute, |
| &SYSTime.wSecond); |
| |
| if(RetVal == 7) { |
| int i; |
| SYSTime.wMilliseconds = 500; /* adjust to midpoint, 0.5 sec */ |
| for(i = 0; i<12; i++) { |
| if(strcmp(MthStr[i], TmpStr2) == 0) { |
| SYSTime.wMonth = i + 1; |
| break; |
| } |
| } |
| AutoSyncTime = 3; /* Computer clock will be adjusted */ |
| } |
| else { |
| AutoSyncTime = 0; /* Error in sscanf() fields conversion */ |
| } |
| } |
| } |
| } |
| |
| if(strncmp((char *)(ptr), "X-Cache: HIT", 12) == 0) { |
| fprintf(stderr, "ERROR: HTTP Server data is cached." |
| " Server Date is no longer valid.\n"); |
| AutoSyncTime = 0; |
| } |
| return (nmemb*size); |
| } |
| |
| void SyncTime_CURL_Init(CURL *curl, char *proxy_port, |
| char *proxy_user_password) |
| { |
| if(strlen(proxy_port) > 0) |
| curl_easy_setopt(curl, CURLOPT_PROXY, proxy_port); |
| |
| if(strlen(proxy_user_password) > 0) |
| curl_easy_setopt(curl, CURLOPT_PROXYUSERPWD, proxy_user_password); |
| |
| #ifdef SYNCTIME_UA |
| curl_easy_setopt(curl, CURLOPT_USERAGENT, SYNCTIME_UA); |
| #endif |
| curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, SyncTime_CURL_WriteOutput); |
| curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, SyncTime_CURL_WriteHeader); |
| } |
| |
| int SyncTime_CURL_Fetch(CURL *curl, char *URL_Str, char *OutFileName, |
| int HttpGetBody) |
| { |
| FILE *outfile; |
| CURLcode res; |
| |
| outfile = NULL; |
| if(HttpGetBody == HTTP_COMMAND_HEAD) |
| curl_easy_setopt(curl, CURLOPT_NOBODY, 1L); |
| else { |
| outfile = fopen(OutFileName, "wb"); |
| curl_easy_setopt(curl, CURLOPT_WRITEDATA, outfile); |
| } |
| |
| curl_easy_setopt(curl, CURLOPT_URL, URL_Str); |
| res = curl_easy_perform(curl); |
| if(outfile) |
| fclose(outfile); |
| return res; /* (CURLE_OK) */ |
| } |
| |
| void showUsage(void) |
| { |
| fprintf(stderr, "SYNCTIME: Synchronising computer clock with time server" |
| " using HTTP protocol.\n"); |
| fprintf(stderr, "Usage : SYNCTIME [Option]\n"); |
| fprintf(stderr, "Options :\n"); |
| fprintf(stderr, " --server=WEBSERVER Use this time server instead" |
| " of default.\n"); |
| fprintf(stderr, " --showall Show all HTTP header.\n"); |
| fprintf(stderr, " --synctime Synchronising computer clock" |
| " with time server.\n"); |
| fprintf(stderr, " --proxy-user=USER[:PASS] Set proxy username and" |
| " password.\n"); |
| fprintf(stderr, " --proxy=HOST[:PORT] Use HTTP proxy on given" |
| " port.\n"); |
| fprintf(stderr, " --help Print this help.\n"); |
| fprintf(stderr, "\n"); |
| return; |
| } |
| |
| int conf_init(conf_t *conf) |
| { |
| int i; |
| |
| *conf->http_proxy = 0; |
| for(i = 0; i<MAX_STRING1; i++) |
| conf->proxy_user[i] = 0; /* Clean up password from memory */ |
| *conf->timeserver = 0; |
| return 1; |
| } |
| |
| int main(int argc, char *argv[]) |
| { |
| CURL *curl; |
| conf_t conf[1]; |
| int RetValue; |
| |
| ShowAllHeader = 0; /* Do not show HTTP Header */ |
| AutoSyncTime = 0; /* Do not synchronise computer clock */ |
| RetValue = 0; /* Successful Exit */ |
| conf_init(conf); |
| |
| if(argc > 1) { |
| int OptionIndex = 0; |
| while(OptionIndex < argc) { |
| if(strncmp(argv[OptionIndex], "--server=", 9) == 0) |
| snprintf(conf->timeserver, MAX_STRING, "%s", &argv[OptionIndex][9]); |
| |
| if(strcmp(argv[OptionIndex], "--showall") == 0) |
| ShowAllHeader = 1; |
| |
| if(strcmp(argv[OptionIndex], "--synctime") == 0) |
| AutoSyncTime = 1; |
| |
| if(strncmp(argv[OptionIndex], "--proxy-user=", 13) == 0) |
| snprintf(conf->proxy_user, MAX_STRING, "%s", &argv[OptionIndex][13]); |
| |
| if(strncmp(argv[OptionIndex], "--proxy=", 8) == 0) |
| snprintf(conf->http_proxy, MAX_STRING, "%s", &argv[OptionIndex][8]); |
| |
| if((strcmp(argv[OptionIndex], "--help") == 0) || |
| (strcmp(argv[OptionIndex], "/?") == 0)) { |
| showUsage(); |
| return 0; |
| } |
| OptionIndex++; |
| } |
| } |
| |
| if(*conf->timeserver == 0) /* Use default server for time information */ |
| snprintf(conf->timeserver, MAX_STRING, "%s", DefaultTimeServer[0]); |
| |
| /* Init CURL before usage */ |
| curl_global_init(CURL_GLOBAL_ALL); |
| curl = curl_easy_init(); |
| if(curl) { |
| struct tm *lt; |
| struct tm *gmt; |
| time_t tt; |
| time_t tt_local; |
| time_t tt_gmt; |
| double tzonediffFloat; |
| int tzonediffWord; |
| char timeBuf[61]; |
| char tzoneBuf[16]; |
| |
| SyncTime_CURL_Init(curl, conf->http_proxy, conf->proxy_user); |
| |
| /* Calculating time diff between GMT and localtime */ |
| tt = time(0); |
| lt = localtime(&tt); |
| tt_local = mktime(lt); |
| gmt = gmtime(&tt); |
| tt_gmt = mktime(gmt); |
| tzonediffFloat = difftime(tt_local, tt_gmt); |
| tzonediffWord = (int)(tzonediffFloat/3600.0); |
| |
| if((double)(tzonediffWord * 3600) == tzonediffFloat) |
| snprintf(tzoneBuf, 15, "%+03d'00'", tzonediffWord); |
| else |
| snprintf(tzoneBuf, 15, "%+03d'30'", tzonediffWord); |
| |
| /* Get current system time and local time */ |
| GetSystemTime(&SYSTime); |
| GetLocalTime(&LOCALTime); |
| snprintf(timeBuf, 60, "%s, %02d %s %04d %02d:%02d:%02d.%03d, ", |
| DayStr[LOCALTime.wDayOfWeek], LOCALTime.wDay, |
| MthStr[LOCALTime.wMonth-1], LOCALTime.wYear, |
| LOCALTime.wHour, LOCALTime.wMinute, LOCALTime.wSecond, |
| LOCALTime.wMilliseconds); |
| |
| fprintf(stderr, "Fetch: %s\n\n", conf->timeserver); |
| fprintf(stderr, "Before HTTP. Date: %s%s\n\n", timeBuf, tzoneBuf); |
| |
| /* HTTP HEAD command to the Webserver */ |
| SyncTime_CURL_Fetch(curl, conf->timeserver, "index.htm", |
| HTTP_COMMAND_HEAD); |
| |
| GetLocalTime(&LOCALTime); |
| snprintf(timeBuf, 60, "%s, %02d %s %04d %02d:%02d:%02d.%03d, ", |
| DayStr[LOCALTime.wDayOfWeek], LOCALTime.wDay, |
| MthStr[LOCALTime.wMonth-1], LOCALTime.wYear, |
| LOCALTime.wHour, LOCALTime.wMinute, LOCALTime.wSecond, |
| LOCALTime.wMilliseconds); |
| fprintf(stderr, "\nAfter HTTP. Date: %s%s\n", timeBuf, tzoneBuf); |
| |
| if(AutoSyncTime == 3) { |
| /* Synchronising computer clock */ |
| if(!SetSystemTime(&SYSTime)) { /* Set system time */ |
| fprintf(stderr, "ERROR: Unable to set system time.\n"); |
| RetValue = 1; |
| } |
| else { |
| /* Successfully re-adjusted computer clock */ |
| GetLocalTime(&LOCALTime); |
| snprintf(timeBuf, 60, "%s, %02d %s %04d %02d:%02d:%02d.%03d, ", |
| DayStr[LOCALTime.wDayOfWeek], LOCALTime.wDay, |
| MthStr[LOCALTime.wMonth-1], LOCALTime.wYear, |
| LOCALTime.wHour, LOCALTime.wMinute, LOCALTime.wSecond, |
| LOCALTime.wMilliseconds); |
| fprintf(stderr, "\nNew System's Date: %s%s\n", timeBuf, tzoneBuf); |
| } |
| } |
| |
| /* Cleanup before exit */ |
| conf_init(conf); |
| curl_easy_cleanup(curl); |
| } |
| return RetValue; |
| } |