[RPCSS] During the setup phase, the RPCSS service, initially running under the LocalSystem account, should re-configure itself to run under the NetworkService account.

This will also fix MS Office 2010 installation, where the installation
expects the NetworkService account profile to be already loaded (this
condition is always verified on Windows since RPCSS and other services
also run under this account).

CORE-14988, CORE-14989

base/services/rpcss/CMakeLists.txt

@@ -8,6 +8,7 @@ list(APPEND SOURCE
     epmp.c
     irotp.c
     rpcss_main.c
+    setup.c
     precomp.h
     ${CMAKE_CURRENT_BINARY_DIR}/epm_s.c
     ${CMAKE_CURRENT_BINARY_DIR}/irot_s.c)

base/services/rpcss/rpcss_main.c

@@ -118,6 +118,10 @@ static DWORD WINAPI service_handler( DWORD ctrl, DWORD event_type, LPVOID event_
     }
 }
 
+#ifdef __REACTOS__
+extern VOID DoRpcSsSetupConfiguration(VOID);
+#endif
+
 static void WINAPI ServiceMain( DWORD argc, LPWSTR *argv )
 {
     SERVICE_STATUS status;
@@ -140,6 +144,10 @@ static void WINAPI ServiceMain( DWORD argc, LPWSTR *argv )
     status.dwWaitHint                = 10000;
     SetServiceStatus( service_handle, &status );
 
+#ifdef __REACTOS__
+    DoRpcSsSetupConfiguration();
+#endif
+
     WaitForSingleObject( exit_event, INFINITE );
 
     status.dwCurrentState     = SERVICE_STOPPED;

base/services/rpcss/setup.c

@@ -0,0 +1,179 @@
+/*
+ * PROJECT:     ReactOS RPC Subsystem Service
+ * LICENSE:     GPL-2.0+ (https://spdx.org/licenses/GPL-2.0+)
+ * PURPOSE:     One-time service setup configuration.
+ * COPYRIGHT:   Copyright 2018 Hermes Belusca-Maito
+ */
+
+/* INCLUDES *****************************************************************/
+
+/* PSDK/NDK Headers */
+#define WIN32_NO_STATUS
+#include <windef.h>
+#include <winbase.h>
+#include <winreg.h>
+#include <winsvc.h>
+
+#include <ndk/rtlfuncs.h>
+#include <ntsecapi.h>
+
+#include "wine/debug.h"
+
+WINE_DEFAULT_DEBUG_CHANNEL(rpcss);
+
+/* FUNCTIONS ****************************************************************/
+
+static BOOL
+SetupIsActive(VOID)
+{
+    LONG lResult;
+    HKEY hKey;
+    DWORD dwData = 0;
+    DWORD cbData = sizeof(dwData);
+    DWORD dwType = REG_NONE;
+
+    lResult = RegOpenKeyExW(HKEY_LOCAL_MACHINE, L"SYSTEM\\Setup", 0, KEY_QUERY_VALUE, &hKey);
+    if (lResult != ERROR_SUCCESS)
+        return FALSE;
+
+    lResult = RegQueryValueExW(hKey, L"SystemSetupInProgress", NULL,
+                               &dwType, (LPBYTE)&dwData, &cbData);
+    RegCloseKey(hKey);
+
+    if ((lResult == ERROR_SUCCESS) && (dwType == REG_DWORD) &&
+        (cbData == sizeof(dwData)) && (dwData == 1))
+    {
+        return TRUE;
+    }
+
+    return FALSE;
+}
+
+static BOOL
+RunningAsSYSTEM(VOID)
+{
+    /* S-1-5-18 -- Local System */
+    static SID SystemSid = { SID_REVISION, 1, { SECURITY_NT_AUTHORITY }, { SECURITY_LOCAL_SYSTEM_RID } };
+
+    BOOL bRet = FALSE;
+    PTOKEN_USER pTokenUser;
+    HANDLE hToken;
+    DWORD cbTokenBuffer = 0;
+
+    /* Get the process token */
+    if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hToken))
+        return FALSE;
+
+    /* Retrieve token's information */
+    if (!GetTokenInformation(hToken, TokenUser, NULL, 0, &cbTokenBuffer) &&
+        GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+    {
+        goto Quit;
+    }
+
+    pTokenUser = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, cbTokenBuffer);
+    if (!pTokenUser)
+        goto Quit;
+
+    if (GetTokenInformation(hToken, TokenUser, pTokenUser, cbTokenBuffer, &cbTokenBuffer))
+    {
+        /* Compare with SYSTEM SID */
+        bRet = EqualSid(pTokenUser->User.Sid, &SystemSid);
+    }
+
+    HeapFree(GetProcessHeap(), 0, pTokenUser);
+
+Quit:
+    CloseHandle(hToken);
+    return bRet;
+}
+
+static VOID
+RpcSsConfigureAsNetworkService(VOID)
+{
+    SC_HANDLE hSCManager, hService;
+
+    /* Open the service controller */
+    hSCManager = OpenSCManagerW(NULL, SERVICES_ACTIVE_DATABASE, SC_MANAGER_CONNECT);
+    if (!hSCManager)
+    {
+        ERR("OpenSCManager() failed with error 0x%lx\n", GetLastError());
+        return;
+    }
+
+    /* Open the RPCSS service */
+    hService = OpenServiceW(hSCManager, L"RPCSS", SERVICE_CHANGE_CONFIG);
+    if (!hService)
+        ERR("OpenService(\"RPCSS\") failed with error 0x%lx\n", GetLastError());
+    if (hService)
+    {
+        /* Use the NetworkService account */
+        if (!ChangeServiceConfigW(hService,
+                                  SERVICE_NO_CHANGE,
+                                  SERVICE_NO_CHANGE,
+                                  SERVICE_NO_CHANGE,
+                                  NULL,
+                                  NULL,
+                                  NULL,
+                                  NULL,
+                                  L"NT AUTHORITY\\NetworkService",
+                                  L"",
+                                  NULL))
+        {
+            ERR("ChangeServiceConfig(\"RPCSS\") failed with error 0x%lx\n", GetLastError());
+        }
+
+        CloseServiceHandle(hService);
+    }
+
+    CloseServiceHandle(hSCManager);
+}
+
+static VOID
+AddImpersonatePrivilege(VOID)
+{
+    /* S-1-5-6 -- "Service" group */
+    static SID ServiceSid = { SID_REVISION, 1, { SECURITY_NT_AUTHORITY }, { SECURITY_SERVICE_RID } };
+
+    NTSTATUS Status;
+    LSA_HANDLE PolicyHandle;
+    LSA_OBJECT_ATTRIBUTES ObjectAttributes;
+    LSA_UNICODE_STRING RightString;
+
+    ZeroMemory(&ObjectAttributes, sizeof(ObjectAttributes));
+    Status = LsaOpenPolicy(NULL, &ObjectAttributes,
+                           POLICY_CREATE_ACCOUNT | POLICY_LOOKUP_NAMES,
+                           &PolicyHandle);
+    if (!NT_SUCCESS(Status))
+    {
+        ERR("LsaOpenPolicy() failed with Status 0x%08lx\n", Status);
+        return;
+    }
+
+    RtlInitUnicodeString(&RightString, L"SeImpersonatePrivilege");
+    Status = LsaAddAccountRights(PolicyHandle, &ServiceSid, &RightString, 1);
+    if (!NT_SUCCESS(Status))
+    {
+        ERR("LsaAddAccountRights(\"S-1-5-6\", \"%wZ\") failed with Status 0x%08lx\n", Status, &RightString);
+    }
+
+    LsaClose(PolicyHandle);
+}
+
+VOID DoRpcSsSetupConfiguration(VOID)
+{
+    /*
+     * On first run during the setup phase, the RPCSS service runs under
+     * the LocalSystem account. RPCSS then re-configures itself to run
+     * under the NetworkService account and adds the Impersonate privilege
+     * to the "Service" group.
+     * This is done in this way, because the NetworkService account does not
+     * initially exist when the setup phase is running and the RPCSS service
+     * is started, but this account is created later during the setup phase.
+     */
+    if (SetupIsActive() && RunningAsSYSTEM())
+    {
+        RpcSsConfigureAsNetworkService();
+        AddImpersonatePrivilege();
+    }
+}