1 files changed, 126 insertions, 0 deletions
diff --git a/src/utils/buf_comp/buf_comp.h b/src/utils/buf_comp/buf_comp.h
new file mode 100644
index 000000000..3f1e90bad
--- /dev/null
+++ b/src/utils/buf_comp/buf_comp.h
@@ -0,0 +1,126 @@
+/**
+* BufferedComputation
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_BUFFERED_COMPUTATION_H__
+#define BOTAN_BUFFERED_COMPUTATION_H__
+
+#include <botan/secmem.h>
+
+namespace Botan {
+
+/**
+* This class represents any kind of computation which
+* uses an internal state,
+* such as hash functions.
+*/
+class BOTAN_DLL BufferedComputation
+   {
+   public:
+
+      /**
+      * The length of the output of this function in bytes.
+      */
+      const u32bit OUTPUT_LENGTH;
+
+      /**
+      * Add new input to process.
+      * @param in the input to process as a byte array
+      * @param the length of the byte array
+      */
+      void update(const byte in[], u32bit length) { add_data(in, length); }
+
+      /**
+      * Add new input to process.
+      * @param in the input to process as a MemoryRegion
+      */
+      void update(const MemoryRegion<byte>& in) { add_data(in, in.size()); }
+
+      /**
+      * Add new input to process.
+      * @param str the input to process as a std::string. Will be interpreted
+      * as a byte array based on
+      * the strings encoding.
+      */
+      void update(const std::string& str)
+         {
+         add_data(reinterpret_cast<const byte*>(str.data()), str.size());
+         }
+
+      /**
+      * Process a single byte.
+      * @param in the byte to process
+      */
+      void update(byte in) { add_data(&in, 1); }
+
+      /**
+      * Complete the computation and retrieve the
+      * final result.
+      * @param out The byte array to be filled with the result.
+      * Must be of length OUTPUT_LENGTH.
+      */
+      void final(byte out[]) { final_result(out); }
+
+      /**
+      * Complete the computation and retrieve the
+      * final result.
+      * @return a SecureVector holding the result
+      */
+      SecureVector<byte> final()
+         {
+         SecureVector<byte> output(OUTPUT_LENGTH);
+         final_result(output);
+         return output;
+         }
+
+      /**
+      * Update and finalize computation. Does the same as calling update()
+      * and final() consecutively.
+      * @param in the input to process as a byte array
+      * @param length the length of the byte array
+      * @result the result of the call to final()
+      */
+      SecureVector<byte> process(const byte in[], u32bit length)
+         {
+         add_data(in, length);
+         return final();
+         }
+
+      /**
+      * Update and finalize computation. Does the same as calling update()
+      * and final() consecutively.
+      * @param in the input to process
+      * @result the result of the call to final()
+      */
+      SecureVector<byte> process(const MemoryRegion<byte>& in)
+         {
+         add_data(in, in.size());
+         return final();
+         }
+
+      /**
+      * Update and finalize computation. Does the same as calling update()
+      * and final() consecutively.
+      * @param in the input to process as a string
+      * @result the result of the call to final()
+      */
+      SecureVector<byte> process(const std::string& in)
+         {
+         update(in);
+         return final();
+         }
+
+      BufferedComputation(u32bit out_len) : OUTPUT_LENGTH(out_len) {}
+      virtual ~BufferedComputation() {}
+   private:
+      BufferedComputation& operator=(const BufferedComputation&);
+      virtual void add_data(const byte[], u32bit) = 0;
+      virtual void final_result(byte[]) = 0;
+   };
+
+}
+
+#endif