path: root/patches/mscodec/mscodec-svx-inc-mscodec-hxx.diff

--- /dev/null	2004-07-26 12:51:14.000000000 +0100
+++ svx/inc/mscodec.hxx	2004-08-11 09:54:04.000000000 +0100
@@ -0,0 +1,326 @@
+/*************************************************************************
+ *
+ *  $RCSfile$
+ *
+ *  $Revision$
+ *
+ *  last change: $Author$ $Date$
+ *
+ *  The Contents of this file are made available subject to the terms of
+ *  either of the following licenses
+ *
+ *         - GNU Lesser General Public License Version 2.1
+ *         - Sun Industry Standards Source License Version 1.1
+ *
+ *  Sun Microsystems Inc., October, 2000
+ *
+ *  GNU Lesser General Public License Version 2.1
+ *  =============================================
+ *  Copyright 2000 by Sun Microsystems, Inc.
+ *  901 San Antonio Road, Palo Alto, CA 94303, USA
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License version 2.1, as published by the Free Software Foundation.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ *  MA  02111-1307  USA
+ *
+ *
+ *  Sun Industry Standards Source License Version 1.1
+ *  =================================================
+ *  The contents of this file are subject to the Sun Industry Standards
+ *  Source License Version 1.1 (the "License"); You may not use this file
+ *  except in compliance with the License. You may obtain a copy of the
+ *  License at http://www.openoffice.org/license.html.
+ *
+ *  Software provided under this License is provided on an "AS IS" basis,
+ *  WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
+ *  WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
+ *  MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
+ *  See the License for the specific provisions governing your rights and
+ *  obligations concerning the Software.
+ *
+ *  The Initial Developer of the Original Code is: Sun Microsystems, Inc.
+ *
+ *  Copyright: 2000 by Sun Microsystems, Inc.
+ *
+ *  All Rights Reserved.
+ *
+ *  Contributor(s): _______________________________________
+ *
+ *
+ ************************************************************************/
+
+#ifndef SVX_MSCODEC_HXX
+#define SVX_MSCODEC_HXX
+
+#ifndef _RTL_CIPHER_H_
+#include "rtl/cipher.h"
+#endif
+#ifndef _RTL_DIGEST_H_
+#include "rtl/digest.h"
+#endif
+
+namespace svx {
+
+// ============================================================================
+
+/** Encodes and decodes data from protected MSO 95- documents.
+ */
+class MSCodec_Xor95
+{
+public:
+    explicit            MSCodec_Xor95(int nRotateDistance);
+    virtual            ~MSCodec_Xor95();
+
+    /** Initializes the algorithm with the specified password.
+
+        @param pPassData
+            Character array containing the password. Must be zero terminated,
+            which results in a maximum length of 15 characters.
+     */
+    void                InitKey( const sal_uInt8 pnPassData[ 16 ] );
+
+    /** Verifies the validity of the password using the passed key and hash.
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+
+        @param nKey
+            Password key value read from the file.
+        @param nHash
+            Password hash value read from the file.
+
+        @return
+            true = Test was successful.
+     */
+    bool                VerifyKey( sal_uInt16 nKey, sal_uInt16 nHash ) const;
+
+    /** Reinitializes the codec to start a new memory block.
+
+        Resets the internal key offset to 0.
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+     */
+    void                InitCipher();
+
+    /** Decodes a block of memory inplace.
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+
+        @param pnData
+            Encrypted data block. Will contain the decrypted data afterwards.
+        @param nBytes
+            Size of the passed data block.
+    */
+    virtual void                Decode( sal_uInt8* pnData, sal_Size nBytes )=0;
+
+    /** Lets the cipher skip a specific amount of bytes.
+
+        This function sets the cipher to the same state as if the specified
+        amount of data has been decoded with one or more calls of Decode().
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+
+        @param nBytes
+            Number of bytes to be skipped (cipher "seeks" forward).
+     */
+    void                Skip( sal_Size nBytes );
+
+    // static -----------------------------------------------------------------
+
+    /** Calculates the 16-bit hash value for the given password.
+
+        The password data may be longer than 16 bytes. The array does not need
+        to be terminated with a NULL byte (but it can without invalidating the
+        result).
+     */
+    static sal_uInt16   GetHash( const sal_uInt8* pnPassData, sal_Size nSize );
+
+protected:
+    sal_uInt8           mpnKey[ 16 ];   /// Encryption key.
+    sal_Size            mnOffset;       /// Key offset.
+
+private:
+                        MSCodec_Xor95( const MSCodec_Xor95& );
+    MSCodec_Xor95&      operator=( const MSCodec_Xor95& );
+
+    sal_uInt16          mnKey;          /// Base key from password.
+    sal_uInt16          mnHash;         /// Hash value from password.
+    int 		mnRotateDistance;
+};
+
+/** Encodes and decodes data from protected MSO XLS 95- documents.
+ */
+class MSCodec_XorXLS95 : public MSCodec_Xor95
+{
+public:
+    explicit            MSCodec_XorXLS95() : MSCodec_Xor95(2) {}
+
+    /** Decodes a block of memory inplace.
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+
+        @param pnData
+            Encrypted data block. Will contain the decrypted data afterwards.
+        @param nBytes
+            Size of the passed data block.
+    */
+    virtual void                Decode( sal_uInt8* pnData, sal_Size nBytes );
+};
+
+/** Encodes and decodes data from protected MSO Word 95- documents.
+ */
+class MSCodec_XorWord95 : public MSCodec_Xor95
+{
+public:
+    explicit            MSCodec_XorWord95() : MSCodec_Xor95(7) {}
+
+    /** Decodes a block of memory inplace.
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+
+        @param pnData
+            Encrypted data block. Will contain the decrypted data afterwards.
+        @param nBytes
+            Size of the passed data block.
+    */
+    virtual void                Decode( sal_uInt8* pnData, sal_Size nBytes );
+};
+
+
+// ============================================================================
+
+/** Encodes and decodes data from protected MSO 97+ documents.
+
+    This is a wrapper class around low level cryptographic functions from RTL.
+    Implementation is based on the wvDecrypt package by Caolan McNamara:
+    http://www.csn.ul.ie/~caolan/docs/wvDecrypt.html
+ */
+class MSCodec_Std97
+{
+public:
+    explicit            MSCodec_Std97();
+                        ~MSCodec_Std97();
+
+    /** Initializes the algorithm with the specified password and document ID.
+
+        @param pPassData
+            Wide character array containing the password. Must be zero
+            terminated, which results in a maximum length of 15 characters.
+        @param pUnique
+            Unique document identifier read from or written to the file.
+     */
+    void                InitKey(
+                            const sal_uInt16 pPassData[ 16 ],
+                            const sal_uInt8 pUnique[ 16 ] );
+
+    /** Verifies the validity of the password using the passed salt data.
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+
+        @param pSaltData
+            Salt data block read from the file.
+        @param pSaltDigest
+            Salt digest read from the file.
+
+        @return
+            true = Test was successful.
+     */
+    bool                VerifyKey(
+                            const sal_uInt8 pSaltData[ 16 ],
+                            const sal_uInt8 pSaltDigest[ 16 ] );
+
+    /** Rekeys the codec using the specified counter.
+
+        After reading a specific amount of data the cipher algorithm needs to
+        be rekeyed using a counter that counts the data blocks.
+
+        The block size is for example 512 Bytes for Word files and 1024 Bytes
+        for Excel files.
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+
+        @param nCounter
+            Block counter used to rekey the cipher.
+     */
+    bool                InitCipher( sal_uInt32 nCounter );
+
+    /** Decodes a block of memory.
+
+        @see rtl_cipher_decode()
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used. The destination buffer must be able to take all
+            encoded data from the source buffer (usually this means it must be
+            as long as or longer than the source buffer).
+
+        @param pData
+            Encrypted source data block.
+        @param nDatLen
+            Size of the passed source data block.
+        @param pBuffer
+            Destination buffer for the decrypted data.
+        @param nBufLen
+            Size of the destination buffer.
+
+        @return
+            true = Decoding was successful (no error occured).
+    */
+    bool                Decode(
+                            const void* pData, sal_Size nDatLen,
+                            sal_uInt8* pBuffer, sal_Size nBufLen );
+
+    /** Lets the cipher skip a specific amount of bytes.
+
+        This function sets the cipher to the same state as if the specified
+        amount of data has been decoded with one or more calls of Decode().
+
+        @precond
+            The codec must be initialized with InitKey() before this function
+            can be used.
+
+        @param nDatLen
+            Number of bytes to be skipped (cipher "seeks" forward).
+     */
+    bool                Skip( sal_Size nDatLen );
+
+private:
+                        MSCodec_Std97( const MSCodec_Std97& );
+    MSCodec_Std97&      operator=( const MSCodec_Std97& );
+
+    rtlCipher           m_hCipher;
+    rtlDigest           m_hDigest;
+    sal_uInt8           m_pDigestValue[ RTL_DIGEST_LENGTH_MD5 ];
+};
+
+// ============================================================================
+
+} // namespace svx
+
+#endif
+