Prepare to handle OOXML Agile Encryption password hash as well

... that prepends the iteration count to the hash instead of
appending it

Change-Id: I090393e6337c110029e35baaa259b40ef4e5d416

2 files changed, 41 insertions, 8 deletions

diff --git a/include/comphelper/docpasswordhelper.hxx b/include/comphelper/docpasswordhelper.hxx
index 51ecb7102abd..0755106b1d23 100644
--- a/include/comphelper/docpasswordhelper.hxx
+++ b/include/comphelper/docpasswordhelper.hxx
@@ -194,11 +194,21 @@ public:
         @param  nSpinCount
                 If >0 the number of repeated iterations.
 
+        @param  bPrependNotAppend
+                If <FALSE/>, append spin count in iterations as per
+                https://msdn.microsoft.com/en-us/library/dd920692
+                If <TRUE/>, prepend spin count in iterations as per
+                https://msdn.microsoft.com/en-us/library/dd924776 and
+                https://msdn.microsoft.com/en-us/library/dd925430
+
         @param  rAlgorithmName
-                One of "SHA-512", "SHA-256", ... as listed in
+                One of "SHA-512", "SHA-256", ... as listed for AlgorithmName in
                 https://msdn.microsoft.com/en-us/library/dd920692
-                that have a valid match in HashType. If not, an empty string is
-                returned. Not all algorithm names are supported.
+                or "SHA512", "SHA256", ... as listed for HashAlgorithm in
+                https://msdn.microsoft.com/en-us/library/dd925810
+                that have a valid match in comphelper::HashType. If not, an
+                empty sequence is returned. Not all algorithm names are
+                supported.
 
         @return the raw hash value as sal_Int8 sequence.
      */
@@ -206,6 +216,7 @@ public:
             const rtl::OUString& rPassword,
             const rtl::OUString& rSaltValue,
             sal_uInt32 nSpinCount,
+            bool bPrependNotAppend,
             const rtl::OUString& rAlgorithmName);
 
 
@@ -223,11 +234,21 @@ public:
         @param  nSpinCount
                 If >0 the number of repeated iterations.
 
+        @param  bPrependNotAppend
+                If <FALSE/>, append spin count in iterations as per
+                https://msdn.microsoft.com/en-us/library/dd920692
+                If <TRUE/>, prepend spin count in iterations as per
+                https://msdn.microsoft.com/en-us/library/dd924776 and
+                https://msdn.microsoft.com/en-us/library/dd925430
+
         @param  rAlgorithmName
-                One of "SHA-512", "SHA-256", ... as listed in
+                One of "SHA-512", "SHA-256", ... as listed for AlgorithmName in
                 https://msdn.microsoft.com/en-us/library/dd920692
-                that have a valid match in HashType. If not, an empty string is
-                returned. Not all algorithm names are supported.
+                or "SHA512", "SHA256", ... as listed for HashAlgorithm in
+                https://msdn.microsoft.com/en-us/library/dd925810
+                that have a valid match in comphelper::HashType. If not, an
+                empty sequence is returned. Not all algorithm names are
+                supported.
 
         @return the base64 encoded string of the hash value, that can be
                 compared against a stored base64 encoded hash value.
@@ -236,6 +257,7 @@ public:
             const rtl::OUString& rPassword,
             const rtl::OUString& rSaltValue,
             sal_uInt32 nSpinCount,
+            bool bPrependNotAppend,
             const rtl::OUString& rAlgorithmName);
 
 
diff --git a/include/comphelper/hash.hxx b/include/comphelper/hash.hxx
index a9cda038b748..9ef2cbd58465 100644
--- a/include/comphelper/hash.hxx
+++ b/include/comphelper/hash.hxx
@@ -54,18 +54,28 @@ public:
         (0-based, little endian) containing the number of the iteration
         appended to the hash value is the input for the next iteration.
 
-        This implements the algorithm as specified in
-        https://msdn.microsoft.com/en-us/library/dd920692
+        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  bPrependNotAppend
+                If <FALSE/>, append spin count in iterations as per
+                https://msdn.microsoft.com/en-us/library/dd920692
+                If <TRUE/>, prepend spin count in iterations as per
+                https://msdn.microsoft.com/en-us/library/dd924776 and
+                https://msdn.microsoft.com/en-us/library/dd925430
+
         @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,
+            bool bPrependNotAppend,
             HashType eType);
 
     /** Convenience function to calculate a salted hash with iterations.
@@ -80,6 +90,7 @@ public:
             const rtl::OUString& rPassword,
             const std::vector<unsigned char>& rSaltValue,
             sal_uInt32 nSpinCount,
+            bool bPrependNotAppend,
             HashType eType);
 
     size_t getLength() const;