[ros-diffs] [fireball] 31768: - Implement canonicalizing the service binary path properly, handling all possible cases (instead of a memory-overwriting hack Christoph noticed yesterday).

Author: fireball
Date: Mon Jan 14 14:46:14 2008
New Revision: 31768
URL: http://svn.reactos.org/svn/reactos?rev=31768&view=rev
Log:
- Implement canonicalizing the service binary path properly, handling all possible cases
(instead of a memory-overwriting hack Christoph noticed yesterday).
Modified:
    trunk/reactos/base/system/services/rpcserver.c
Modified: trunk/reactos/base/system/services/rpcserver.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/base/system/services/rpcse…
==============================================================================
--- trunk/reactos/base/system/services/rpcserver.c (original)
+++ trunk/reactos/base/system/services/rpcserver.c Mon Jan 14 14:46:14 2008
@@ -993,6 +993,380 @@
     DPRINT("ScmrChangeServiceConfigW() done (Error %lu)\n", dwError);
     return dwError;
+}
+
+/* Create a path suitable for the bootloader out of the full path */
+DWORD
+ScmConvertToBootPathName(wchar_t *CanonName, wchar_t **RelativeName)
+{
+    DWORD ServiceNameLen, BufferSize, ExpandedLen;
+    WCHAR Dest;
+    WCHAR *Expanded;
+    UNICODE_STRING NtPathName, SystemRoot, LinkTarget;
+    OBJECT_ATTRIBUTES ObjectAttributes;
+    NTSTATUS Status;
+    HANDLE SymbolicLinkHandle;
+
+    DPRINT("ScmConvertToBootPathName %S\n", CanonName);
+
+    ServiceNameLen = wcslen(CanonName);
+    /* First check, if it's already good */
+    if (ServiceNameLen > 12 &&
+        !wcsnicmp(L"\\SystemRoot\\", CanonName, 12))
+    {
+        *RelativeName = LocalAlloc(LMEM_ZEROINIT, ServiceNameLen * sizeof(WCHAR) +
sizeof(WCHAR));
+
+        if (*RelativeName == NULL)
+        {
+            DPRINT1("Error allocating memory for boot driver name!\n");
+            return ERROR_NOT_ENOUGH_MEMORY;
+        }
+
+        /* Copy it */
+        wcscpy(*RelativeName, CanonName);
+
+        DPRINT1("Bootdriver name %S\n", *RelativeName);
+        return ERROR_SUCCESS;
+    }
+
+    /* If it has %SystemRoot% prefix, substitute it to \System*/
+    if (ServiceNameLen > 13 &&
+        !wcsnicmp(L"%SystemRoot%\\", CanonName, 13))
+    {
+        /* There is no +sizeof(wchar_t) because the name is less by 1 wchar */
+        *RelativeName = LocalAlloc(LMEM_ZEROINIT, ServiceNameLen * sizeof(WCHAR));
+
+        if (*RelativeName == NULL)
+        {
+            DPRINT1("Error allocating memory for boot driver name!\n");
+            return ERROR_NOT_ENOUGH_MEMORY;
+        }
+
+        /* Copy it */
+        wcscpy(*RelativeName, L"\\SystemRoot\\");
+        wcscat(*RelativeName, CanonName + 13);
+
+        DPRINT1("Bootdriver name %S\n", *RelativeName);
+        return ERROR_SUCCESS;
+    }
+
+    /* Get buffer size needed for expanding env strings */
+    BufferSize = ExpandEnvironmentStringsW(L"%SystemRoot%\\", &Dest, 1);
+
+    if (BufferSize <= 1)
+    {
+        DPRINT1("Error during a call to ExpandEnvironmentStringsW()\n");
+        return ERROR_INVALID_ENVIRONMENT;
+    }
+
+    /* Allocate memory, since the size is known now */
+    Expanded = LocalAlloc(LMEM_ZEROINIT, BufferSize * sizeof(WCHAR) + sizeof(WCHAR));
+    if (!Expanded)
+    {
+            DPRINT1("Error allocating memory for boot driver name!\n");
+            return ERROR_NOT_ENOUGH_MEMORY;
+    }
+
+    /* Expand it */
+    if (ExpandEnvironmentStringsW(L"%SystemRoot%\\", Expanded, BufferSize) >
+        BufferSize)
+    {
+        DPRINT1("Error during a call to ExpandEnvironmentStringsW()\n");
+        LocalFree(Expanded);
+        return ERROR_NOT_ENOUGH_MEMORY;
+    }
+
+    /* Convert to NY-style path */
+    if (!RtlDosPathNameToNtPathName_U(Expanded, &NtPathName, NULL, NULL))
+    {
+        DPRINT1("Error during a call to RtlDosPathNameToNtPathName_U()\n");
+        return ERROR_INVALID_ENVIRONMENT;
+    }
+
+    DPRINT("Converted to NT-style %wZ\n", &NtPathName);
+
+    /* No need to keep the dos-path anymore */
+    LocalFree(Expanded);
+
+    /* Copy it to the allocated place */
+    Expanded = LocalAlloc(LMEM_ZEROINIT, NtPathName.Length + sizeof(WCHAR));
+    if (!Expanded)
+    {
+            DPRINT1("Error allocating memory for boot driver name!\n");
+            return ERROR_NOT_ENOUGH_MEMORY;
+    }
+
+    ExpandedLen = NtPathName.Length / sizeof(WCHAR);
+    wcsncpy(Expanded, NtPathName.Buffer, ExpandedLen);
+    Expanded[ExpandedLen] = 0;
+
+    if (ServiceNameLen > ExpandedLen &&
+        !wcsnicmp(Expanded, CanonName, ExpandedLen))
+    {
+        /* Only \SystemRoot\ is missing */
+        *RelativeName = LocalAlloc(LMEM_ZEROINIT,
+            (ServiceNameLen - ExpandedLen) * sizeof(WCHAR) + 13*sizeof(WCHAR));
+
+        if (*RelativeName == NULL)
+        {
+            DPRINT1("Error allocating memory for boot driver name!\n");
+            LocalFree(Expanded);
+            return ERROR_NOT_ENOUGH_MEMORY;
+        }
+
+        wcscpy(*RelativeName, L"\\SystemRoot\\");
+        wcscat(*RelativeName, CanonName + ExpandedLen);
+
+        RtlFreeUnicodeString(&NtPathName);
+        return ERROR_SUCCESS;
+    }
+
+    /* The most complex case starts here */
+    RtlInitUnicodeString(&SystemRoot, L"\\SystemRoot");
+    InitializeObjectAttributes(&ObjectAttributes,
+                               &SystemRoot,
+                               OBJ_CASE_INSENSITIVE,
+                               NULL,
+                               NULL);
+
+    /* Open this symlink */
+    Status = NtOpenSymbolicLinkObject(&SymbolicLinkHandle, SYMBOLIC_LINK_QUERY,
&ObjectAttributes);
+
+    if (NT_SUCCESS(Status))
+    {
+        LinkTarget.Length = 0;
+        LinkTarget.MaximumLength = 0;
+
+        DPRINT("Opened symbolic link object\n");
+
+        Status = NtQuerySymbolicLinkObject(SymbolicLinkHandle, &LinkTarget,
&BufferSize);
+        if (NT_SUCCESS(Status) || Status == STATUS_BUFFER_TOO_SMALL)
+        {
+            /* Check if required buffer size is sane */
+            if (BufferSize > 0xFFFD)
+            {
+                DPRINT1("Too large buffer required\n");
+                *RelativeName = 0;
+
+                if (SymbolicLinkHandle) NtClose(SymbolicLinkHandle);
+                LocalFree(Expanded);
+                return ERROR_NOT_ENOUGH_MEMORY;
+            }
+
+            /* Alloc the string */
+            LinkTarget.Buffer = LocalAlloc(LMEM_ZEROINIT, BufferSize + sizeof(WCHAR));
+            if (!LinkTarget.Buffer)
+            {
+                DPRINT1("Unable to alloc buffer\n");
+                if (SymbolicLinkHandle) NtClose(SymbolicLinkHandle);
+                LocalFree(Expanded);
+                return ERROR_NOT_ENOUGH_MEMORY;
+            }
+
+            /* Do a real query now */
+            LinkTarget.Length = BufferSize;
+            LinkTarget.MaximumLength = LinkTarget.Length + sizeof(WCHAR);
+
+            Status = NtQuerySymbolicLinkObject(SymbolicLinkHandle, &LinkTarget,
&BufferSize);
+            if (NT_SUCCESS(Status))
+            {
+                DPRINT("LinkTarget: %wZ\n", &LinkTarget);
+
+                ExpandedLen = LinkTarget.Length / sizeof(WCHAR);
+                if ((ServiceNameLen > ExpandedLen) &&
+                    !wcsnicmp(LinkTarget.Buffer, CanonName, ExpandedLen))
+                {
+                    *RelativeName = LocalAlloc(LMEM_ZEROINIT,
+                       (ServiceNameLen - ExpandedLen) * sizeof(WCHAR) +
13*sizeof(WCHAR));
+
+                    if (*RelativeName == NULL)
+                    {
+                        DPRINT1("Unable to alloc buffer\n");
+                        if (SymbolicLinkHandle) NtClose(SymbolicLinkHandle);
+                        LocalFree(Expanded);
+                        RtlFreeUnicodeString(&NtPathName);
+                        return ERROR_NOT_ENOUGH_MEMORY;
+                    }
+
+                    /* Copy it over, substituting the first part
+                       with SystemRoot */
+                    wcscpy(*RelativeName, L"\\SystemRoot\\");
+                    wcscat(*RelativeName, CanonName+ExpandedLen+1);
+
+                    /* Cleanup */
+                    if (SymbolicLinkHandle) NtClose(SymbolicLinkHandle);
+                    LocalFree(Expanded);
+                    RtlFreeUnicodeString(&NtPathName);
+
+                    /* Return success */
+                    return ERROR_SUCCESS;
+                }
+                else
+                {
+                    if (SymbolicLinkHandle) NtClose(SymbolicLinkHandle);
+                    LocalFree(Expanded);
+                    RtlFreeUnicodeString(&NtPathName);
+                    return ERROR_INVALID_PARAMETER;
+                }
+            }
+            else
+            {
+                DPRINT1("Error, Status = %08X\n", Status);
+                if (SymbolicLinkHandle) NtClose(SymbolicLinkHandle);
+                LocalFree(Expanded);
+                RtlFreeUnicodeString(&NtPathName);
+                return ERROR_INVALID_PARAMETER;
+            }
+        }
+        else
+        {
+            DPRINT1("Error, Status = %08X\n", Status);
+            if (SymbolicLinkHandle) NtClose(SymbolicLinkHandle);
+            LocalFree(Expanded);
+            RtlFreeUnicodeString(&NtPathName);
+            return ERROR_INVALID_PARAMETER;
+        }
+    }
+    else
+    {
+        DPRINT1("Error, Status = %08X\n", Status);
+        LocalFree(Expanded);
+        return ERROR_INVALID_PARAMETER;
+    }
+
+    /* Failure */
+    *RelativeName = NULL;
+    return ERROR_INVALID_PARAMETER;
+}
+
+DWORD
+ScmCanonDriverImagePath(DWORD dwStartType,
+                        wchar_t *lpServiceName,
+                        wchar_t **lpCanonName)
+{
+    DWORD ServiceNameLen, Result;
+    UNICODE_STRING NtServiceName;
+    WCHAR *RelativeName;
+    WCHAR *SourceName = lpServiceName;
+
+    /* Calculate the length of the service's name */
+    ServiceNameLen = wcslen(lpServiceName);
+
+    /* 12 is wcslen(L"\\SystemRoot\\") */
+    if (ServiceNameLen > 12 &&
+        !wcsnicmp(L"\\SystemRoot\\", lpServiceName, 12))
+    {
+        /* SystemRoot prefix is already included */
+
+        *lpCanonName = LocalAlloc(LMEM_ZEROINIT, ServiceNameLen * sizeof(WCHAR) +
sizeof(WCHAR));
+
+        if (*lpCanonName == NULL)
+        {
+            DPRINT1("Error allocating memory for canonized service name!\n");
+            return ERROR_NOT_ENOUGH_MEMORY;
+        }
+
+        /* If it's a boot-time driver, it must be systemroot relative */
+        if (dwStartType == SERVICE_BOOT_START)
+            SourceName += 12;
+
+        /* Copy it */
+        wcscpy(*lpCanonName, SourceName);
+
+        DPRINT("Canonicalized name %S\n", *lpCanonName);
+        return NO_ERROR;
+    }
+
+    /* Check if it has %SystemRoot% (len=13) */
+    if (ServiceNameLen > 13 &&
+        !wcsnicmp(L"%SystemRoot%\\", lpServiceName, 13))
+    {
+        /* Substitute %SystemRoot% with \\SystemRoot\\ */
+        *lpCanonName = LocalAlloc(LMEM_ZEROINIT, ServiceNameLen * sizeof(WCHAR) +
sizeof(WCHAR));
+
+        if (*lpCanonName == NULL)
+        {
+            DPRINT1("Error allocating memory for canonized service name!\n");
+            return ERROR_NOT_ENOUGH_MEMORY;
+        }
+
+        /* If it's a boot-time driver, it must be systemroot relative */
+        if (dwStartType == SERVICE_BOOT_START)
+            wcscpy(*lpCanonName, L"\\SystemRoot\\");
+
+        wcscat(*lpCanonName, lpServiceName);
+
+        DPRINT("Canonicalized name %S\n", *lpCanonName);
+        return NO_ERROR;
+    }
+
+    /* Check if it's a relative path name */
+    if (lpServiceName[0] != L'\\' && lpServiceName[1] != L':')
+    {
+        *lpCanonName = LocalAlloc(LMEM_ZEROINIT, ServiceNameLen * sizeof(WCHAR) +
sizeof(WCHAR));
+
+        if (*lpCanonName == NULL)
+        {
+            DPRINT1("Error allocating memory for canonized service name!\n");
+            return ERROR_NOT_ENOUGH_MEMORY;
+        }
+
+        /* Just copy it over without changing */
+        wcscpy(*lpCanonName, lpServiceName);
+
+        return NO_ERROR;
+    }
+
+    /* It seems to be a DOS path, convert it */
+    if (!RtlDosPathNameToNtPathName_U(lpServiceName, &NtServiceName, NULL, NULL))
+    {
+        DPRINT1("RtlDosPathNameToNtPathName_U() failed!\n");
+        return ERROR_INVALID_PARAMETER;
+    }
+
+    *lpCanonName = LocalAlloc(LMEM_ZEROINIT, NtServiceName.Length + sizeof(WCHAR));
+
+    if (*lpCanonName == NULL)
+    {
+        DPRINT1("Error allocating memory for canonized service name!\n");
+        RtlFreeUnicodeString(&NtServiceName);
+        return ERROR_NOT_ENOUGH_MEMORY;
+    }
+
+    /* Copy the string */
+    wcsncpy(*lpCanonName, NtServiceName.Buffer, NtServiceName.Length / sizeof(WCHAR));
+
+    /* The unicode string is not needed anymore */
+    RtlFreeUnicodeString(&NtServiceName);
+
+    if (dwStartType != SERVICE_BOOT_START)
+    {
+        DPRINT("Canonicalized name %S\n", *lpCanonName);
+        return NO_ERROR;
+    }
+
+    /* The service is boot-started, so must be relative */
+    Result = ScmConvertToBootPathName(*lpCanonName, &RelativeName);
+    if (Result)
+    {
+        /* There is a problem, free name and return */
+        LocalFree(*lpCanonName);
+        DPRINT1("Error converting named!\n");
+        return Result;
+    }
+
+    ASSERT(RelativeName);
+
+    /* Copy that string */
+    wcscpy(*lpCanonName, RelativeName + 12);
+
+    /* Free the allocated buffer */
+    LocalFree(RelativeName);
+
+    DPRINT("Canonicalized name %S\n", *lpCanonName);
+
+    /* Success */
+    return NO_ERROR;
 }
@@ -1058,24 +1432,12 @@
     if (dwServiceType & SERVICE_DRIVER)
     {
-        lpImagePath = (WCHAR*) HeapAlloc(GetProcessHeap(),
-                                HEAP_ZERO_MEMORY,
-                                (wcslen(lpBinaryPathName) + 5) * sizeof(WCHAR));
-        if (lpImagePath == NULL)
-        {
-            dwError = ERROR_NOT_ENOUGH_MEMORY;
+        dwError = ScmCanonDriverImagePath(dwStartType,
+            lpBinaryPathName,
+            &lpImagePath);
+
+        if (dwError != ERROR_SUCCESS)
             goto done;
-        }
-
-        if (lpBinaryPathName[1] == L':')
-        {
-            wcscpy(lpImagePath, L"\\??\\");
-            wcscat(lpImagePath, lpBinaryPathName);
-        }
-        else
-        {
-            wcscpy(lpImagePath, lpBinaryPathName);
-        }
     }
     /* Allocate a new service entry */