Wininet库忽略Https证书
相信很多朋友使用C++ WINAPI开发的时候网络模块的时候遇到Https忽悠证书无效的情况下，
仍然希望获取结果下列代码便是忽略异常的Https CA证书，下面对原理进行简单的讲解首先,
需要设置Https忽略需要用到如下结果函数与参数InternetQueryOptionA/InternetSetOptionA
参数需要SECURITY_FLAG_IGNORE_UNKNOWN_CA,下面建议先阅读下代码可以发现忽略Https证书
是发生在HttpSendRequestA之后设置这是因为InternetConnect主要负责主要负责建立与服务器
的连接，而涉及到CA（Certificate Authority）的验证通常是在建立连接后的HTTP请求阶段进行的,
CA的验证是在SSL/TLS握手过程中完成的，而握手过程通常是在 HttpSendRequestA被调用时发生。
因此，在建立连接时，我们还没有进入HTTP请求的阶段，所以无法在 InternetConnect 之前
处理CA验证的问题,因此下列代码是进行这样忽略的首先HttpSendRequestA返回ERROR_INTERNET_INVALID_CA
出现CA证书异常这个时候需要忽略证书无效，InternetQueryOptionA获取当前的安全选项然后
追加上SECURITY_FLAG_IGNORE_UNKNOWN_CA忽略证书无效CA将设置后的值通过InternetSetOptionA
函数应用再次发起HttpSendRequestA即可忽略CA证书进行下一步操作。
#include <Windows.h>
#include <Wininet.h>
#include <stdio.h>
#pragma comment(lib, "wininet.lib")#define TRANSFER_SIZE 1024
bool PerformHttpRequest() {LPCSTR lpszAgent = "";HINTERNET hInternet = InternetOpenA(lpszAgent, INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);if (!hInternet) {return false; }LPCSTR lpszServerName = "192.168.99.111"; INTERNET_PORT nServerPort = INTERNET_DEFAULT_HTTPS_PORT; LPCSTR lpszUserName = NULL; LPCSTR lpszPassword = NULL; DWORD dwConnectFlags = 0;DWORD dwConnectContext = 0;HINTERNET hConnect = InternetConnectA(hInternet,lpszServerName, nServerPort,lpszUserName, lpszPassword,INTERNET_SERVICE_HTTP,dwConnectFlags, dwConnectContext);if (!hConnect) {InternetCloseHandle(hInternet);return false; }LPCSTR lpszVerb = "GET";LPCSTR lpszObjectName = "/Login";LPCSTR lpszVersion = NULL; LPCSTR lpszReferrer = NULL; LPCSTR* lplpszAcceptTypes = NULL; DWORD dwOpenRequestFlags = INTERNET_FLAG_IGNORE_REDIRECT_TO_HTTP |INTERNET_FLAG_KEEP_CONNECTION |INTERNET_FLAG_NO_AUTH |INTERNET_FLAG_NO_COOKIES |INTERNET_FLAG_NO_UI |INTERNET_FLAG_SECURE |INTERNET_FLAG_IGNORE_CERT_CN_INVALID |INTERNET_FLAG_RELOAD;DWORD dwOpenRequestContext = 0;HINTERNET hRequest = HttpOpenRequestA(hConnect, lpszVerb, lpszObjectName, lpszVersion,lpszReferrer, lplpszAcceptTypes,dwOpenRequestFlags, dwOpenRequestContext);if (!hRequest) {InternetCloseHandle(hConnect);InternetCloseHandle(hInternet);return false; }BOOL bResult = HttpSendRequestA(hRequest, NULL, 0, NULL, 0);if (!bResult && GetLastError() == ERROR_INTERNET_INVALID_CA) {DWORD dwFlags;DWORD dwBuffLen = sizeof(dwFlags);InternetQueryOptionA(hRequest, INTERNET_OPTION_SECURITY_FLAGS, (LPVOID)&dwFlags, &dwBuffLen);dwFlags |= SECURITY_FLAG_IGNORE_UNKNOWN_CA;InternetSetOptionA(hRequest, INTERNET_OPTION_SECURITY_FLAGS, &dwFlags, sizeof(dwFlags));bResult = HttpSendRequestA(hRequest, NULL, 0, NULL, 0);}if (!bResult) {InternetCloseHandle(hRequest);InternetCloseHandle(hConnect);InternetCloseHandle(hInternet);return false; }char szBuff[TRANSFER_SIZE];DWORD dwReadSize = TRANSFER_SIZE;bResult = HttpQueryInfoA(hRequest, HTTP_QUERY_RAW_HEADERS_CRLF, szBuff, &dwReadSize, NULL);if (!bResult) {InternetCloseHandle(hRequest);InternetCloseHandle(hConnect);InternetCloseHandle(hInternet);return false; }szBuff[dwReadSize] = '\0';printf("%s\n", szBuff);DWORD dwBytesAvailable;bResult = InternetQueryDataAvailable(hRequest, &dwBytesAvailable, 0, 0);if (!bResult) {InternetCloseHandle(hRequest);InternetCloseHandle(hConnect);InternetCloseHandle(hInternet);return false; }if (dwBytesAvailable > TRANSFER_SIZE) {printf("数据太长 %d /b", GetLastError(), dwBytesAvailable);InternetCloseHandle(hRequest);InternetCloseHandle(hConnect);InternetCloseHandle(hInternet);return false; }DWORD dwBytesRead;bResult = InternetReadFile(hRequest, szBuff, dwBytesAvailable, &dwBytesRead);if (!bResult) {InternetCloseHandle(hRequest);InternetCloseHandle(hConnect);InternetCloseHandle(hInternet);return false; }szBuff[dwBytesRead] = '\0';printf("%s\n", szBuff);InternetCloseHandle(hRequest);InternetCloseHandle(hConnect);InternetCloseHandle(hInternet);return true;
}int main() {if (PerformHttpRequest()) {return 0;}else {return 1;}
}
综合实验)
