From 6c6813d7f7ded25015decb1f5c07f8f1c28779b9 Mon Sep 17 00:00:00 2001
From: Eric Kohl <eric.kohl@reactos.org>
Date: Sat, 3 Sep 2016 15:06:20 +0000
Subject: [PATCH] [SAMSRV] SamrQuerySecurityObject: Return security information
 according to the SecurityInformation parameter.

svn path=/trunk/; revision=72547
---
 reactos/dll/win32/samsrv/samrpc.c | 94 +++++++++++++++++++++----------
 1 file changed, 65 insertions(+), 29 deletions(-)

diff --git a/reactos/dll/win32/samsrv/samrpc.c b/reactos/dll/win32/samsrv/samrpc.c
index aa81c2f6d4c..9d957dbe0a2 100644
--- a/reactos/dll/win32/samsrv/samrpc.c
+++ b/reactos/dll/win32/samsrv/samrpc.c
@@ -218,10 +218,12 @@ SamrQuerySecurityObject(IN SAMPR_HANDLE ObjectHandle,
                         OUT PSAMPR_SR_SECURITY_DESCRIPTOR *SecurityDescriptor)
 {
     PSAM_DB_OBJECT SamObject;
-    PSAMPR_SR_SECURITY_DESCRIPTOR SamSD = NULL;
-    PSECURITY_DESCRIPTOR SdBuffer = NULL;
+    PSAMPR_SR_SECURITY_DESCRIPTOR SdData = NULL;
+    PSECURITY_DESCRIPTOR RelativeSd = NULL;
+    PSECURITY_DESCRIPTOR ResultSd = NULL;
     ACCESS_MASK DesiredAccess = 0;
-    ULONG Length = 0;
+    ULONG RelativeSdSize = 0;
+    ULONG ResultSdSize = 0;
     NTSTATUS Status;
 
     TRACE("(%p %lx %p)\n",
@@ -248,64 +250,98 @@ SamrQuerySecurityObject(IN SAMPR_HANDLE ObjectHandle,
     if (!NT_SUCCESS(Status))
         goto done;
 
-    SamSD = midl_user_allocate(sizeof(SAMPR_SR_SECURITY_DESCRIPTOR));
-    if (SamSD == NULL)
-    {
-        Status = STATUS_INSUFFICIENT_RESOURCES;
-        goto done;
-    }
-
+    /* Get the size of the SD */
     Status = SampGetObjectAttribute(SamObject,
                                     L"SecDesc",
                                     NULL,
                                     NULL,
-                                    &Length);
+                                    &RelativeSdSize);
     if (!NT_SUCCESS(Status) && Status != STATUS_BUFFER_OVERFLOW)
     {
         TRACE("Status 0x%08lx\n", Status);
         goto done;
     }
 
-    TRACE("SD Length: %lu\n", Length);
-
-    SdBuffer = midl_user_allocate(Length);
-    if (SdBuffer == NULL)
+    /* Allocate a buffer for the SD */
+    RelativeSd = midl_user_allocate(RelativeSdSize);
+    if (RelativeSd == NULL)
     {
         Status = STATUS_INSUFFICIENT_RESOURCES;
         goto done;
     }
 
+    /* Get the SD */
     Status = SampGetObjectAttribute(SamObject,
                                     L"SecDesc",
                                     NULL,
-                                    SdBuffer,
-                                    &Length);
+                                    RelativeSd,
+                                    &RelativeSdSize);
     if (!NT_SUCCESS(Status))
     {
         TRACE("Status 0x%08lx\n", Status);
         goto done;
     }
 
-    /* FIXME: Use SecurityInformation to return only the requested information */
+    /* Invalidate the SD information that was not requested */
+    if (!(SecurityInformation & OWNER_SECURITY_INFORMATION))
+        ((PISECURITY_DESCRIPTOR)RelativeSd)->Owner = NULL;
 
-    SamSD->Length = Length;
-    SamSD->SecurityDescriptor = SdBuffer;
+    if (!(SecurityInformation & GROUP_SECURITY_INFORMATION))
+        ((PISECURITY_DESCRIPTOR)RelativeSd)->Group = NULL;
+
+    if (!(SecurityInformation & DACL_SECURITY_INFORMATION))
+        ((PISECURITY_DESCRIPTOR)RelativeSd)->Control &= ~SE_DACL_PRESENT;
+
+    if (!(SecurityInformation & SACL_SECURITY_INFORMATION))
+        ((PISECURITY_DESCRIPTOR)RelativeSd)->Control &= ~SE_SACL_PRESENT;
+
+    /* Calculate the required SD size */
+    Status = RtlMakeSelfRelativeSD(RelativeSd,
+                                   NULL,
+                                   &ResultSdSize);
+    if (Status != STATUS_BUFFER_TOO_SMALL)
+        goto done;
+
+    /* Allocate a buffer for the new SD */
+    ResultSd = MIDL_user_allocate(ResultSdSize);
+    if (ResultSd == NULL)
+    {
+        Status = STATUS_INSUFFICIENT_RESOURCES;
+        goto done;
+    }
+
+    /* Build the new SD */
+    Status = RtlMakeSelfRelativeSD(RelativeSd,
+                                   ResultSd,
+                                   &ResultSdSize);
+    if (!NT_SUCCESS(Status))
+        goto done;
+
+    /* Allocate the SD data buffer */
+    SdData = midl_user_allocate(sizeof(SAMPR_SR_SECURITY_DESCRIPTOR));
+    if (SdData == NULL)
+    {
+        Status = STATUS_INSUFFICIENT_RESOURCES;
+        goto done;
+    }
+
+    /* Fill the SD data buffer and return it to the caller */
+    SdData->Length = RelativeSdSize;
+    SdData->SecurityDescriptor = (PBYTE)ResultSd;
+
+    *SecurityDescriptor = SdData;
 
 done:
     RtlReleaseResource(&SampResource);
 
-    if (NT_SUCCESS(Status))
+    if (!NT_SUCCESS(Status))
     {
-        *SecurityDescriptor = SamSD;
+        if (ResultSd != NULL)
+            MIDL_user_free(ResultSd);
     }
-    else
-    {
-        if (SdBuffer != NULL)
-            midl_user_free(SdBuffer);
 
-        if (SamSD != NULL)
-            midl_user_free(SamSD);
-    }
+    if (RelativeSd != NULL)
+        MIDL_user_free(RelativeSd);
 
     return Status;
 }