1 files changed, 121 insertions, 0 deletions
diff --git a/include/comphelper/hash.hxx b/include/comphelper/hash.hxx
new file mode 100644
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--- /dev/null
+++ b/include/comphelper/hash.hxx
@@ -0,0 +1,121 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#ifndef INCLUDED_COMPHELPER_HASH_HXX
+#define INCLUDED_COMPHELPER_HASH_HXX
+
+#include <comphelper/comphelperdllapi.h>
+#include <rtl/digest.h>
+
+#include <memory>
+#include <vector>
+
+namespace rtl {
+    class OUString;
+}
+
+namespace comphelper {
+
+enum class HashType
+{
+    MD5,
+    SHA1,
+    SHA256,
+    SHA512
+};
+
+const sal_uInt32 MD5_HASH_LENGTH = RTL_DIGEST_LENGTH_MD5;
+const sal_uInt32 SHA1_HASH_LENGTH = RTL_DIGEST_LENGTH_SHA1;
+const sal_uInt32 SHA256_HASH_LENGTH = 32;
+const sal_uInt32 SHA512_HASH_LENGTH = 64;
+
+struct HashImpl;
+
+class COMPHELPER_DLLPUBLIC Hash
+{
+private:
+    std::unique_ptr<HashImpl> mpImpl;
+
+public:
+
+    enum class IterCount
+    {
+        NONE,       /// Iteration count not added to hash iterations.
+        PREPEND,    /// Iteration count prepended to hash iterations.
+        APPEND      /// Iteration count appended to hash iterations.
+    };
+
+    Hash(HashType eType);
+    ~Hash();
+
+    void update(const unsigned char* pInput, size_t length);
+
+    std::vector<unsigned char> finalize();
+
+    static std::vector<unsigned char> calculateHash(const unsigned char* pInput, size_t length, HashType eType);
+
+    /** Calculate hash value with salt (pSalt,nSaltLen) prepended to password
+        (pInput,nLength) and repeated iterations run if nSpinCount>0.
+
+        This implements the algorithms as specified in
+        https://msdn.microsoft.com/en-us/library/dd920692 or
+        https://msdn.microsoft.com/en-us/library/dd924776 and
+        https://msdn.microsoft.com/en-us/library/dd925430
+
+        @param  pSalt
+                may be nullptr thus no salt prepended
+
+        @param  nSpinCount
+                If >0, repeat nSpinCount iterations. For each iteration, the
+                previous iteration's result plus a 4 byte value (0-based,
+                little endian) containing the number of the iteration prepended
+                or appended to the hash value is the input for the next
+                iteration.
+
+        @param  eIterCount
+                If IterCount::APPEND, append iteration count as per
+                https://msdn.microsoft.com/en-us/library/dd920692
+                If IterCount::PREPEND, prepend iteration count as per
+                https://msdn.microsoft.com/en-us/library/dd924776 and
+                https://msdn.microsoft.com/en-us/library/dd925430
+                If IterCount::NONE, do not add the iteration count to hash
+                iterations.
+
+        @return the raw hash value
+     */
+    static std::vector<unsigned char> calculateHash(
+            const unsigned char* pInput, size_t nLength,
+            const unsigned char* pSalt, size_t nSaltLen,
+            sal_uInt32 nSpinCount,
+            IterCount eIterCount,
+            HashType eType);
+
+    /** Convenience function to calculate a salted hash with iterations.
+
+        @param  rPassword
+                UTF-16 encoded string, hashed byte-wise as unsigned char.
+
+        @param  rSaltValue
+                Salt that will be prepended to password data.
+     */
+    static std::vector<unsigned char> calculateHash(
+            const rtl::OUString& rPassword,
+            const std::vector<unsigned char>& rSaltValue,
+            sal_uInt32 nSpinCount,
+            IterCount eIterCount,
+            HashType eType);
+
+    size_t getLength() const;
+};
+
+}
+
+#endif // INCLUDED_COMPHELPER_HASH_HXX
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */