applied patch #1687456 - [UserInfo plugin] Fix for #1684777, GetAccountType and Vista

git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@5033 212acab6-be3b-0410-9dea-997c60f758d6

Contrib/UserInfo/UserInfo.c

@@ -1,5 +1,7 @@
 #include <windows.h>
 #include "../ExDLL/exdll.h"
+typedef BOOL (WINAPI*CHECKTOKENMEMBERSHIP)(HANDLE TokenHandle,PSID SidToCheck,PBOOL IsMember);
+CHECKTOKENMEMBERSHIP _CheckTokenMembership=NULL;
 
 void __declspec(dllexport) GetName(HWND hwndParent, int string_size, 
                                    char *variables, stack_t **stacktop)
@@ -17,102 +19,127 @@ void __declspec(dllexport) GetName(HWND hwndParent, int string_size,
   }
 }
 
-void __declspec(dllexport) GetAccountType(HWND hwndParent, int string_size, 
+char* GetAccountTypeHelper(BOOL CheckTokenForGroupDeny) 
-                                          char *variables, stack_t **stacktop)
 {
-  EXDLL_INIT();
+  char  *group;
-
+  HANDLE  hToken = NULL;
-  {
-    HANDLE        hThread;
-    TOKEN_GROUPS  *ptg = NULL;
-    DWORD         cbTokenGroups;
-    DWORD         i, j;
-
-    SID_IDENTIFIER_AUTHORITY SystemSidAuthority = {SECURITY_NT_AUTHORITY};
-
-    char *group = "";
-
-    if (GetVersion() & 0x80000000) // Not NT
-    {
-      group = "Admin";
-    }
-
-    // First we must open a handle to the access token for this thread.
-
-    else if (OpenThreadToken(GetCurrentThread(), TOKEN_QUERY, FALSE, &hThread) ||
-        OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hThread))
-    {
-      // Then we must query the size of the group information associated with
-      // the token. Note that we expect a FALSE result from GetTokenInformation
-      // because we've given it a NULL buffer. On exit cbTokenGroups will tell
-      // the size of the group information.
-
-      if (!GetTokenInformation (hThread, TokenGroups, NULL, 0, &cbTokenGroups) &&
-          GetLastError() == ERROR_INSUFFICIENT_BUFFER)
-      {
-
-        // Now we allocate a buffer for the group information.
-        // Since _alloca allocates on the stack, we don't have
-        // to explicitly deallocate it. That happens automatically
-        // when we exit this function.
-
-        if ((ptg = GlobalAlloc(GPTR, cbTokenGroups)))
-        {
-
-          // Now we ask for the group information again.
-          // This may fail if an administrator has added this account
-          // to an additional group between our first call to
-          // GetTokenInformation and this one.
-
-          if (GetTokenInformation(hThread, TokenGroups, ptg, cbTokenGroups, &cbTokenGroups))
-          {
-
   struct group
   {
     DWORD auth_id;
     char *name;
-            } groups[] = {
+  };
+
+  struct group groups[] = 
+  {
     {DOMAIN_ALIAS_RID_USERS, "User"},
-              // every user belongs to the users group, hence users comes before guests
+    // every user belongs to the users group, hence users come before guests
     {DOMAIN_ALIAS_RID_GUESTS, "Guest"},
     {DOMAIN_ALIAS_RID_POWER_USERS, "Power"},
     {DOMAIN_ALIAS_RID_ADMINS, "Admin"}
   };
 
-            // Finally we'll iterate through the list of groups for this access
+  if (GetVersion() & 0x80000000) // Not NT
-            // token looking for a match against the SID we created above.
+  {
+    return "Admin";
+  }
 
+  // First we must open a handle to the access token for this thread.
+  if (OpenThreadToken(GetCurrentThread(), TOKEN_QUERY, FALSE, &hToken) ||
+    OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hToken))
+  {
+    SID_IDENTIFIER_AUTHORITY SystemSidAuthority = {SECURITY_NT_AUTHORITY};
+    TOKEN_GROUPS  *ptg          = NULL;
+    BOOL       ValidTokenGroups = FALSE;
+    DWORD      cbTokenGroups;
+    DWORD      i, j;
+    
+    
+    if (CheckTokenForGroupDeny)
+      // GetUserName is in advapi32.dll so we can avoid Load/Freelibrary
+      _CheckTokenMembership=
+        (CHECKTOKENMEMBERSHIP) GetProcAddress(
+          GetModuleHandle("ADVAPI32"), "CheckTokenMembership");
+    
+    // Use "old school" membership check?
+    if (!CheckTokenForGroupDeny || _CheckTokenMembership == NULL)
+    {
+      // We must query the size of the group information associated with
+      // the token. Note that we expect a FALSE result from GetTokenInformation
+      // because we've given it a NULL buffer. On exit cbTokenGroups will tell
+      // the size of the group information.
+      if (!GetTokenInformation(hToken, TokenGroups, NULL, 0, &cbTokenGroups) &&
+        GetLastError() == ERROR_INSUFFICIENT_BUFFER)
+      {
+        // Allocate buffer and ask for the group information again.
+        // This may fail if an administrator has added this account
+        // to an additional group between our first call to
+        // GetTokenInformation and this one.
+        if ((ptg = GlobalAlloc(GPTR, cbTokenGroups)) &&
+          GetTokenInformation(hToken, TokenGroups, ptg, cbTokenGroups, &cbTokenGroups))
+        {
+          ValidTokenGroups=TRUE;
+        }
+      }
+    }
+    
+    if (ValidTokenGroups || (CheckTokenForGroupDeny && _CheckTokenMembership))
+    {
+      PSID psid;
       for (i = 0; i < sizeof(groups)/sizeof(struct group); i++)
       {
-              PSID psid = 0;
+        // Create a SID for the local group and then check if it exists in our token
-              AllocateAndInitializeSid(
+        if (AllocateAndInitializeSid(
-                &SystemSidAuthority,
+          &SystemSidAuthority, 2, SECURITY_BUILTIN_DOMAIN_RID,
-                2,
+          groups[i].auth_id, 0, 0, 0, 0, 0, 0,&psid))
-                SECURITY_BUILTIN_DOMAIN_RID,
+        {
-                groups[i].auth_id,
+          BOOL IsMember = FALSE;
-                0, 0, 0, 0, 0, 0,
+          if (CheckTokenForGroupDeny && _CheckTokenMembership)
-                &psid
+          {
-              );
+            _CheckTokenMembership(0, psid, &IsMember);
-              if (psid == 0) continue;
+          }
+          else if (ValidTokenGroups)
+          {
             for (j = 0; j < ptg->GroupCount; j++)
+            {
               if (EqualSid(ptg->Groups[j].Sid, psid))
-                  group = groups[i].name;
+              {
+                IsMember = TRUE;
+              }
+            }
+          }
+          
+          if (IsMember) group=groups[i].name;
           FreeSid(psid);
         }
       }
+    }
 
+    if (ptg)
       GlobalFree(ptg);
-        }
+    CloseHandle(hToken);
+
+    return group;
   }
 
-      CloseHandle(hThread);
+  return "";
 }
 
-    pushstring(group);
+void __declspec(dllexport) GetAccountType(HWND hwndParent, int string_size, 
+                                          char *variables, stack_t **stacktop)
+{
+  EXDLL_INIT();
+  pushstring(GetAccountTypeHelper(TRUE));
 }
+
+void __declspec(dllexport) GetOriginalAccountType(HWND hwndParent, int string_size, 
+                                                  char *variables, stack_t **stacktop)
+{
+  EXDLL_INIT();
+  pushstring(GetAccountTypeHelper(FALSE));
 }
 
 BOOL WINAPI DllMain(HANDLE hInst, ULONG ul_reason_for_call, LPVOID lpReserved)
 {
   return TRUE;
 }
+

Contrib/UserInfo/UserInfo.nsi

@@ -1,6 +1,8 @@
 Name "UserInfo.dll test"
 OutFile UserInfo.exe
 
+!define REALMSG "$\nOriginal non-restricted account type: $2"
+
 Section
 	ClearErrors
 	UserInfo::GetName
@@ -8,17 +10,26 @@ Section
 	Pop $0
 	UserInfo::GetAccountType
 	Pop $1
+	# GetOriginalAccountType will check the tokens of the original user of the
+	# current thread/process. If the user tokens were elevated or limited for
+	# this process, GetOriginalAccountType will return the non-restricted
+	# account type.
+	# On Vista with UAC, for example, this is not the same value when running
+	# with `RequestExecutionLevel user`. GetOriginalAccountType will return
+	# "admin" while GetAccountType will return "user".
+	UserInfo::GetOriginalAccountType
+	Pop $2
 	StrCmp $1 "Admin" 0 +3
-		MessageBox MB_OK 'User "$0" is in the Administrators group'
+		MessageBox MB_OK 'User "$0" is in the Administrators group${REALMSG}'
 		Goto done
 	StrCmp $1 "Power" 0 +3
-		MessageBox MB_OK 'User "$0" is in the Power Users group'
+		MessageBox MB_OK 'User "$0" is in the Power Users group${REALMSG}'
 		Goto done
 	StrCmp $1 "User" 0 +3
-		MessageBox MB_OK 'User "$0" is just a regular user'
+		MessageBox MB_OK 'User "$0" is just a regular user${REALMSG}'
 		Goto done
 	StrCmp $1 "Guest" 0 +3
-		MessageBox MB_OK 'User "$0" is a guest'
+		MessageBox MB_OK 'User "$0" is a guest${REALMSG}'
 		Goto done
 	MessageBox MB_OK "Unknown error"
 	Goto done
@@ -30,3 +41,4 @@ Section
 
 	done:
 SectionEnd
+