1 files changed, 56 insertions, 0 deletions

diff --git a/src/experimental/ciphermodeofb.h b/src/experimental/ciphermodeofb.h
new file mode 100644
index 0000000..8c2aa20
--- /dev/null
+++ b/src/experimental/ciphermodeofb.h
@@ -0,0 +1,56 @@
+#ifndef BU_MODE_OFB_H
+#define BU_MODE_OFB_H
+
+#include "bu/filter.h"
+#include "bu/string.h"
+
+namespace Bu
+{
+        template<int iBlockSize, typename CipherType>
+        class CipherModeOfb : public CipherType
+        {
+        public:
+                CipherModeOfb(class Stream &rNext ) :
+                        CipherType( rNext ),
+                        bStart( true )
+                {
+                        memset( aVector, 0, iBlockSize );
+                }
+
+                virtual ~CipherModeOfb()
+                {
+                }
+
+                void setIv( const Bu::String &sIv )
+                {
+                        memcpy( aVector, sIv.getStr(), iBlockSize );
+                }
+
+        protected:
+                void decipher( void *pBuf )
+                {
+                        CipherType::encipher( aVector );
+                        uint8_t aTmp[iBlockSize];
+                        memcpy( aTmp, aVector, iBlockSize );
+                        for( int j = 0; j < iBlockSize; j++ )
+                                ((uint8_t *)pBuf)[j] ^= aVector[j];
+                        memcpy( aVector, aTmp, iBlockSize );
+                }
+
+                void encipher( void *pBuf )
+                {
+                        CipherType::encipher( aVector );
+                        uint8_t aTmp[iBlockSize];
+                        memcpy( aTmp, aVector, iBlockSize );
+                        for( int j = 0; j < iBlockSize; j++ )
+                                ((uint8_t *)pBuf)[j] ^= aVector[j];
+                        memcpy( aVector, aTmp, iBlockSize );
+                }
+
+        private:
+                bool bStart;
+                uint8_t aVector[iBlockSize];
+        };
+};
+
+#endif