ku: UUID v5 generation

src/ku/uuid5.c

@@ -0,0 +1,134 @@
+/**
+ * @file dll/uuid5.c
+ *
+ * @copyright 2015-2019 Bill Zissimopoulos
+ */
+/*
+ * This file is part of WinFsp.
+ *
+ * You can redistribute it and/or modify it under the terms of the GNU
+ * General Public License version 3 as published by the Free Software
+ * Foundation.
+ *
+ * Licensees holding a valid commercial license may use this software
+ * in accordance with the commercial license agreement provided in
+ * conjunction with the software.  The terms and conditions of any such
+ * commercial license agreement shall govern, supersede, and render
+ * ineffective any application of the GPLv3 license to this software,
+ * notwithstanding of any reference thereto in the software or
+ * associated repository.
+ */
+
+#include <ku/library.h>
+#include <bcrypt.h>
+
+/*
+ * This module is used to create UUID v5 identifiers. UUID v5 identifiers
+ * are effectively SHA1 hashes that are modified to fit within the UUID
+ * format. The resulting identifiers use version 5 and variant 2. The hash
+ * is taken over the concatenation of a namespace ID and a name; the namespace
+ * ID is another UUID and the name can be any string of bytes ("octets").
+ *
+ * For details see RFC 4122: https://tools.ietf.org/html/rfc4122
+ */
+
+NTSTATUS FspUuid5Make(const UUID *Namespace, const VOID *Buffer, ULONG Size, UUID *Uuid)
+{
+    BCRYPT_ALG_HANDLE ProvHandle = 0;
+    BCRYPT_HASH_HANDLE HashHandle = 0;
+    UINT8 Temp[20];
+    NTSTATUS Result;
+
+    /*
+     * Windows UUID's are encoded in little-endian format. RFC 4122 specifies that for
+     * UUID v5 computation, UUID's must be converted to/from big-endian.
+     *
+     * Note that Windows is always little-endian:
+     * https://community.osr.com/discussion/comment/146810/#Comment_146810
+     */
+
+    /* copy Namespace to local buffer in network byte order (big-endian) */
+    Temp[ 0] = ((PUINT8)Namespace)[ 3];
+    Temp[ 1] = ((PUINT8)Namespace)[ 2];
+    Temp[ 2] = ((PUINT8)Namespace)[ 1];
+    Temp[ 3] = ((PUINT8)Namespace)[ 0];
+    Temp[ 4] = ((PUINT8)Namespace)[ 5];
+    Temp[ 5] = ((PUINT8)Namespace)[ 4];
+    Temp[ 6] = ((PUINT8)Namespace)[ 7];
+    Temp[ 7] = ((PUINT8)Namespace)[ 6];
+    Temp[ 8] = ((PUINT8)Namespace)[ 8];
+    Temp[ 9] = ((PUINT8)Namespace)[ 9];
+    Temp[10] = ((PUINT8)Namespace)[10];
+    Temp[11] = ((PUINT8)Namespace)[11];
+    Temp[12] = ((PUINT8)Namespace)[12];
+    Temp[13] = ((PUINT8)Namespace)[13];
+    Temp[14] = ((PUINT8)Namespace)[14];
+    Temp[15] = ((PUINT8)Namespace)[15];
+
+    /*
+     * Unfortunately we cannot reuse the hashing object, because BCRYPT_HASH_REUSABLE_FLAG
+     * is available in Windows 8 and later. (WinFsp currently supports Windows 7 or later).
+     */
+
+    Result = BCryptOpenAlgorithmProvider(&ProvHandle, BCRYPT_SHA1_ALGORITHM, 0, 0);
+    if (!NT_SUCCESS(Result))
+        goto exit;
+
+    Result = BCryptCreateHash(ProvHandle, &HashHandle, 0, 0, 0, 0, 0);
+    if (!NT_SUCCESS(Result))
+        goto exit;
+
+    Result = BCryptHashData(HashHandle, (PVOID)Temp, 16, 0);
+    if (!NT_SUCCESS(Result))
+        goto exit;
+
+    Result = BCryptHashData(HashHandle, (PVOID)Buffer, Size, 0);
+    if (!NT_SUCCESS(Result))
+        goto exit;
+
+    Result = BCryptFinishHash(HashHandle, Temp, 20, 0);
+    if (!NT_SUCCESS(Result))
+        goto exit;
+
+    /* copy local buffer to Uuid in host byte order (little-endian) */
+    ((PUINT8)Uuid)[ 0] = Temp[ 3];
+    ((PUINT8)Uuid)[ 1] = Temp[ 2];
+    ((PUINT8)Uuid)[ 2] = Temp[ 1];
+    ((PUINT8)Uuid)[ 3] = Temp[ 0];
+    ((PUINT8)Uuid)[ 4] = Temp[ 5];
+    ((PUINT8)Uuid)[ 5] = Temp[ 4];
+    ((PUINT8)Uuid)[ 6] = Temp[ 7];
+    ((PUINT8)Uuid)[ 7] = Temp[ 6];
+    ((PUINT8)Uuid)[ 8] = Temp[ 8];
+    ((PUINT8)Uuid)[ 9] = Temp[ 9];
+    ((PUINT8)Uuid)[10] = Temp[10];
+    ((PUINT8)Uuid)[11] = Temp[11];
+    ((PUINT8)Uuid)[12] = Temp[12];
+    ((PUINT8)Uuid)[13] = Temp[13];
+    ((PUINT8)Uuid)[14] = Temp[14];
+    ((PUINT8)Uuid)[15] = Temp[15];
+
+    /* [RFC 4122 Section 4.3]
+     * Set the four most significant bits (bits 12 through 15) of the
+     * time_hi_and_version field to the appropriate 4-bit version number
+     * from Section 4.1.3.
+     */
+    Uuid->Data3 = (5 << 12) | (Uuid->Data3 & 0x0fff);
+
+    /* [RFC 4122 Section 4.3]
+     * Set the two most significant bits (bits 6 and 7) of the
+     * clock_seq_hi_and_reserved to zero and one, respectively.
+     */
+    Uuid->Data4[0] = (2 << 6) | (Uuid->Data4[0] & 0x3f);
+
+    Result = STATUS_SUCCESS;
+
+exit:
+    if (0 != HashHandle)
+        BCryptDestroyHash(HashHandle);
+
+    if (0 != ProvHandle)
+        BCryptCloseAlgorithmProvider(ProvHandle, 0);
+
+    return Result;
+}

src/sys/driver.h

@@ -493,6 +493,9 @@ NTSTATUS FspFileNameInExpression(
     PWCH UpcaseTable,
     PBOOLEAN PResult);
 
+/* UUID5 creation (ku) */
+NTSTATUS FspUuid5Make(const UUID *Namespace, const VOID *Buffer, ULONG Size, UUID *Uuid);
+
 /* utility */
 PVOID FspAllocatePoolMustSucceed(POOL_TYPE PoolType, SIZE_T Size, ULONG Tag);
 PVOID FspAllocateIrpMustSucceed(CCHAR StackSize);