Zebediah Figura : msi: Create the custom action server as an elevated process.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 366398cc53c76028c8dfe8d8a16c78a6a10ce962
URL:    https://gitlab.winehq.org/wine/wine/-/commit/366398cc53c76028c8dfe8d8a16c78a...

Author: Zebediah Figura 
Date:   Sun May 16 20:49:05 2021 -0500

msi: Create the custom action server as an elevated process.

Dragon Naturally Speaking 12.5 manually validates that the custom action server
is elevated.

One might imagine that the right approach here is to add a manifest to msiexec;
however, msiexec does not always trigger a UAC prompt on Windows.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=51143

---

dlls/msi/custom.c | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/dlls/msi/custom.c b/dlls/msi/custom.c
index d1e064f5b65..12a7c3c3676 100644
--- a/dlls/msi/custom.c
+++ b/dlls/msi/custom.c
@@ -573,12 +573,28 @@ UINT CDECL __wine_msi_call_dll_function(DWORD client_pid, const GUID *guid)
     return r;
 }

+static HANDLE get_admin_token(void)
+{
+    TOKEN_ELEVATION_TYPE type;
+    TOKEN_LINKED_TOKEN linked;
+    DWORD size;
+
+    if (!GetTokenInformation(GetCurrentThreadEffectiveToken(), TokenElevationType, &type, sizeof(type), &size)
+            || type == TokenElevationTypeFull)
+        return NULL;
+
+    if (!GetTokenInformation(GetCurrentThreadEffectiveToken(), TokenLinkedToken, &linked, sizeof(linked), &size))
+        return NULL;
+    return linked.LinkedToken;
+}
+
 static DWORD custom_start_server(MSIPACKAGE *package, DWORD arch)
 {
     WCHAR path[MAX_PATH], cmdline[MAX_PATH + 23];
     PROCESS_INFORMATION pi = {0};
     STARTUPINFOW si = {0};
     WCHAR buffer[24];
+    HANDLE token;
     void *cookie;
     HANDLE pipe;

@@ -600,14 +616,18 @@ static DWORD custom_start_server(MSIPACKAGE *package, DWORD arch)
     lstrcatW(path, L"\msiexec.exe");
     swprintf(cmdline, ARRAY_SIZE(cmdline), L"%s -Embedding %d", path, GetCurrentProcessId());

+    token = get_admin_token();
+
     if (is_wow64 && arch == SCS_64BIT_BINARY)
     {
         Wow64DisableWow64FsRedirection(&cookie);
-        CreateProcessW(path, cmdline, NULL, NULL, FALSE, 0, NULL, NULL, &si, &pi);
+        CreateProcessAsUserW(token, path, cmdline, NULL, NULL, FALSE, 0, NULL, NULL, &si, &pi);
         Wow64RevertWow64FsRedirection(cookie);
     }
     else
-        CreateProcessW(path, cmdline, NULL, NULL, FALSE, 0, NULL, NULL, &si, &pi);
+        CreateProcessAsUserW(token, path, cmdline, NULL, NULL, FALSE, 0, NULL, NULL, &si, &pi);
+
+    if (token) CloseHandle(token);

CloseHandle(pi.hThread);