从Windows系统服务获取活动用户的注册表信息（当前活动用户的sessionId. 当前活动用户的 hUserToken）

首先，对“活动用户”的定义是，当前拥有桌面的用户。对于Windows XP及其以后的系统，即使是可以多个用户同时登录了，拥有桌面的也仅仅只有一个。 
如果系统级服务调用Windows API来获取注册表键值的时候，直接以HKEY_CURRENT_USER为参数，则取到的并不是活动用户的注册表信息，而是系统用户的注册表信息，即，位于HKEY_LOCAL_MACHINE之下的。那么如何以系统服务的身份获取活动用户（真正的HKEY_CURRENT_USER）之下的注册表信息呢？主要有以下这么几步：

1. 系统服务程序调用 WTSGetActiveConsoleSessionId() 以获取当前活动用户的sessionId.
2. 以此sessionId为参数，调用 WTSQueryUserToken() 以获取当前活动用户的 hUserToken.
3. 以此hUserToken为参数，调用 DuplicateTokenEx() 以复制一个token，如hFakeToken.
4. 以此hFakeToken为参数，调用 ImpersonateLoggedOnUser() 以模拟活动用户登录的环境.
5. 调用 RegOpenCurrentUser() 以打开活动用户的 HKEY_CURRENT_USER.
6. 调用 RegOpenKeyEx() 以获取指定位置的注册表键值.

以QT和Windows API来实现的代码如下：

void GetUserRegistryFromSystemService() { #ifdef Q_OS_WIN DWORD sessionId = WTSGetActiveConsoleSessionId(); qInfo() << "Session ID = " << sessionId; wchar_t * ppUserName[100]; DWORD sizeOfUserName; WTSQuerySessionInformation(WTS_CURRENT_SERVER_HANDLE, sessionId, WTSUserName, ppUserName, &sizeOfUserName); qInfo() << "Windows User Name = " << QString::fromWCharArray(*ppUserName); std::wstring strValueOfBinDir = L"Unknown Value"; LONG regOpenResult = ERROR_SUCCESS; HANDLE hUserToken = NULL; HANDLE hFakeToken = NULL; if (WTSQueryUserToken(sessionId, &hUserToken)) { if (DuplicateTokenEx(hUserToken, TOKEN_ASSIGN_PRIMARY | TOKEN_ALL_ACCESS, 0, SecurityImpersonation, TokenPrimary, &hFakeToken) == TRUE) { if (ImpersonateLoggedOnUser(hFakeToken)) { HKEY hKey; regOpenResult = RegOpenCurrentUser(KEY_READ, &hKey); if (regOpenResult != ERROR_SUCCESS) { qCritical() << "Failed to call RegOpenCurrentUser(), Error is " << regOpenResult; } HKEY hSubKey; RegOpenKeyEx(hKey, TEXT("Software\\Baidu\\BaiduYunGuanjia"), 0, KEY_READ, &hSubKey); GetStringRegKey(hSubKey, TEXT("installDir"), strValueOfBinDir, TEXT("Unknown")); RevertToSelf(); } else { qCritical() << "Failed to ImpersonateLoggedOnUser..."; } CloseHandle(hFakeToken); } else { qCritical() << "Failed to call DuplicateTokenEx..."; } CloseHandle(hUserToken); } else { qCritical() << "Failed to get the user token of session " << sessionId; } qInfo() << "The value of Registry is " << QString::fromWCharArray( strValueOfBinDir.c_str() ); #endif }

最后，取注册表信息一些方法：

HKEY hKey;
LONG lRes = RegOpenKeyExW(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Perl", 0, KEY_READ, &hKey); bool bExistsAndSuccess (lRes == ERROR_SUCCESS); bool bDoesNotExistsSpecifically (lRes == ERROR_FILE_NOT_FOUND); std::wstring strValueOfBinDir; std::wstring strKeyDefaultValue; GetStringRegKey(hKey, L"BinDir", strValueOfBinDir, L"bad"); GetStringRegKey(hKey, L"", strKeyDefaultValue, L"bad"); LONG GetStringRegKey(HKEY hKey, const std::wstring &strValueName, std::wstring &strValue, const std::wstring &strDefaultValue) { strValue = strDefaultValue; WCHAR szBuffer[512]; DWORD dwBufferSize = sizeof(szBuffer); ULONG nError; nError = RegQueryValueExW(hKey, strValueName.c_str(), 0, NULL, (LPBYTE)szBuffer, &dwBufferSize); if (ERROR_SUCCESS == nError) { strValue = szBuffer; } return nError; } LONG GetDWORDRegKey(HKEY hKey, const std::wstring &strValueName, DWORD &nValue, DWORD nDefaultValue) { nValue = nDefaultValue; DWORD dwBufferSize(sizeof(DWORD)); DWORD nResult(0); LONG nError = ::RegQueryValueExW(hKey, strValueName.c_str(), 0, NULL, reinterpret_cast<LPBYTE>(&nResult), &dwBufferSize); if (ERROR_SUCCESS == nError) { nValue = nResult; } return nError; } LONG GetBoolRegKey(HKEY hKey, const std::wstring &strValueName, bool &bValue, bool bDefaultValue) { DWORD nDefValue((bDefaultValue) ? 1 : 0); DWORD nResult(nDefValue); LONG nError = GetDWORDRegKey(hKey, strValueName.c_str(), nResult, nDefValue); if (ERROR_SUCCESS == nError) { bValue = (nResult != 0) ? true : false; } return nError; } 

 

http://blog.csdn.net/nirendao/article/details/52077637