1 files changed, 50 insertions, 0 deletions

diff --git a/src/ext/Util/ca/scanet.cpp b/src/ext/Util/ca/scanet.cpp
new file mode 100644
index 00000000..11ee487d
--- /dev/null
+++ b/src/ext/Util/ca/scanet.cpp
@@ -0,0 +1,50 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+#include "precomp.h"
+#include "scanet.h"
+
+
+HRESULT GetDomainServerName(LPCWSTR pwzDomain, LPWSTR* ppwzServerName, ULONG flags)
+{
+    DWORD er = ERROR_SUCCESS;
+    PDOMAIN_CONTROLLER_INFOW pDomainControllerInfo = NULL;
+    HRESULT hr = S_OK;
+
+    if (pwzDomain && *pwzDomain)
+    {
+        er = ::DsGetDcNameW(NULL, pwzDomain, NULL, NULL, flags, &pDomainControllerInfo);
+        if (RPC_S_SERVER_UNAVAILABLE == er)
+        {
+            // MSDN says, if we get the above error code, try again with the "DS_FORCE_REDISCOVERY" flag
+            er = ::DsGetDcNameW(NULL, pwzDomain, NULL, NULL, flags | DS_FORCE_REDISCOVERY, &pDomainControllerInfo);
+        }
+
+        if (ERROR_SUCCESS == er && pDomainControllerInfo->DomainControllerName)
+        {
+            // Skip the \\ prefix if present.
+            if ('\\' == *pDomainControllerInfo->DomainControllerName && '\\' == *pDomainControllerInfo->DomainControllerName + 1)
+            {
+                hr = StrAllocString(ppwzServerName, pDomainControllerInfo->DomainControllerName + 2, 0);
+                ExitOnFailure(hr, "failed to allocate memory for string");
+            }
+            else
+            {
+                hr = StrAllocString(ppwzServerName, pDomainControllerInfo->DomainControllerName, 0);
+                ExitOnFailure(hr, "failed to allocate memory for string");
+            }
+        }
+        else
+        {
+            StrAllocString(ppwzServerName, pwzDomain, 0);
+            hr = HRESULT_FROM_WIN32(er);
+            ExitOnFailure(hr, "failed to contact domain %ls", pwzDomain);
+        }
+    }
+
+LExit:
+    if (pDomainControllerInfo)
+    {
+        ::NetApiBufferFree((LPVOID)pDomainControllerInfo);
+    }
+    return hr;
+}