Move most of what was left in core to utils (since that is what they are,

basically). buf_comp and data_src might need their own directory, but it
doesn't really feel like it.

7 files changed, 1174 insertions, 1 deletions

diff --git a/src/utils/buf_comp.h b/src/utils/buf_comp.h
new file mode 100644
index 000000000..c05324b8f
--- /dev/null
+++ b/src/utils/buf_comp.h
@@ -0,0 +1,124 @@
+/**
+* BufferedComputation
+* (C) 1999-2007 Jack Lloyd
+*/
+
+#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
diff --git a/src/utils/data_src.cpp b/src/utils/data_src.cpp
new file mode 100644
index 000000000..de5544885
--- /dev/null
+++ b/src/utils/data_src.cpp
@@ -0,0 +1,205 @@
+/*************************************************
+* DataSource Source File                         *
+* (C) 1999-2007 Jack Lloyd                       *
+*     2005 Matthew Gregan                        *
+*************************************************/
+
+#include <botan/data_src.h>
+#include <botan/exceptn.h>
+
+#include <fstream>
+#include <algorithm>
+
+namespace Botan {
+
+/*************************************************
+* Read a single byte from the DataSource         *
+*************************************************/
+u32bit DataSource::read_byte(byte& out)
+   {
+   return read(&out, 1);
+   }
+
+/*************************************************
+* Peek a single byte from the DataSource         *
+*************************************************/
+u32bit DataSource::peek_byte(byte& out) const
+   {
+   return peek(&out, 1, 0);
+   }
+
+/*************************************************
+* Discard the next N bytes of the data           *
+*************************************************/
+u32bit DataSource::discard_next(u32bit n)
+   {
+   u32bit discarded = 0;
+   byte dummy;
+   for(u32bit j = 0; j != n; ++j)
+      discarded = read_byte(dummy);
+   return discarded;
+   }
+
+/*************************************************
+* Read from a memory buffer                      *
+*************************************************/
+u32bit DataSource_Memory::read(byte out[], u32bit length)
+   {
+   u32bit got = std::min(source.size() - offset, length);
+   copy_mem(out, source + offset, got);
+   offset += got;
+   return got;
+   }
+
+/*************************************************
+* Peek into a memory buffer                      *
+*************************************************/
+u32bit DataSource_Memory::peek(byte out[], u32bit length,
+                               u32bit peek_offset) const
+   {
+   const u32bit bytes_left = source.size() - offset;
+   if(peek_offset >= bytes_left) return 0;
+
+   u32bit got = std::min(bytes_left - peek_offset, length);
+   copy_mem(out, source + offset + peek_offset, got);
+   return got;
+   }
+
+/*************************************************
+* Check if the memory buffer is empty            *
+*************************************************/
+bool DataSource_Memory::end_of_data() const
+   {
+   return (offset == source.size());
+   }
+
+/*************************************************
+* DataSource_Memory Constructor                  *
+*************************************************/
+DataSource_Memory::DataSource_Memory(const byte in[], u32bit length)
+   {
+   source.set(in, length);
+   offset = 0;
+   }
+
+/*************************************************
+* DataSource_Memory Constructor                  *
+*************************************************/
+DataSource_Memory::DataSource_Memory(const MemoryRegion<byte>& in)
+   {
+   source = in;
+   offset = 0;
+   }
+
+/*************************************************
+* DataSource_Memory Constructor                  *
+*************************************************/
+DataSource_Memory::DataSource_Memory(const std::string& in)
+   {
+   source.set(reinterpret_cast<const byte*>(in.data()), in.length());
+   offset = 0;
+   }
+
+/*************************************************
+* Read from a stream                             *
+*************************************************/
+u32bit DataSource_Stream::read(byte out[], u32bit length)
+   {
+   source->read(reinterpret_cast<char*>(out), length);
+   if(source->bad())
+      throw Stream_IO_Error("DataSource_Stream::read: Source failure");
+
+   u32bit got = source->gcount();
+   total_read += got;
+   return got;
+   }
+
+/*************************************************
+* Peek into a stream                             *
+*************************************************/
+u32bit DataSource_Stream::peek(byte out[], u32bit length, u32bit offset) const
+   {
+   if(end_of_data())
+      throw Invalid_State("DataSource_Stream: Cannot peek when out of data");
+
+   u32bit got = 0;
+
+   if(offset)
+      {
+      SecureVector<byte> buf(offset);
+      source->read(reinterpret_cast<char*>(buf.begin()), buf.size());
+      if(source->bad())
+         throw Stream_IO_Error("DataSource_Stream::peek: Source failure");
+      got = source->gcount();
+      }
+
+   if(got == offset)
+      {
+      source->read(reinterpret_cast<char*>(out), length);
+      if(source->bad())
+         throw Stream_IO_Error("DataSource_Stream::peek: Source failure");
+      got = source->gcount();
+      }
+
+   if(source->eof())
+      source->clear();
+   source->seekg(total_read, std::ios::beg);
+
+   return got;
+   }
+
+/*************************************************
+* Check if the stream is empty or in error       *
+*************************************************/
+bool DataSource_Stream::end_of_data() const
+   {
+   return (!source->good());
+   }
+
+/*************************************************
+* Return a human-readable ID for this stream     *
+*************************************************/
+std::string DataSource_Stream::id() const
+   {
+   return identifier;
+   }
+
+/*************************************************
+* DataSource_Stream Constructor                  *
+*************************************************/
+DataSource_Stream::DataSource_Stream(const std::string& path,
+                                     bool use_binary) :
+   identifier(path), owner(true)
+   {
+   if(use_binary)
+      source = new std::ifstream(path.c_str(), std::ios::binary);
+   else
+      source = new std::ifstream(path.c_str());
+
+   if(!source->good())
+      throw Stream_IO_Error("DataSource: Failure opening file " + path);
+
+   total_read = 0;
+   }
+
+/*************************************************
+* DataSource_Stream Constructor                  *
+*************************************************/
+DataSource_Stream::DataSource_Stream(std::istream& in,
+                                     const std::string& name) :
+   identifier(name), owner(false)
+   {
+   source = &in;
+   total_read = 0;
+   }
+
+/*************************************************
+* DataSource_Stream Destructor                   *
+*************************************************/
+DataSource_Stream::~DataSource_Stream()
+   {
+   if(owner)
+      delete source;
+   }
+
+}
diff --git a/src/utils/data_src.h b/src/utils/data_src.h
new file mode 100644
index 000000000..25bdce00f
--- /dev/null
+++ b/src/utils/data_src.h
@@ -0,0 +1,148 @@
+/*************************************************
+* DataSource Header File                         *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#ifndef BOTAN_DATA_SRC_H__
+#define BOTAN_DATA_SRC_H__
+
+#include <botan/secmem.h>
+#include <string>
+#include <iosfwd>
+
+namespace Botan {
+
+/**
+* This class represents an abstract data source object.
+*/
+class BOTAN_DLL DataSource
+   {
+   public:
+      /**
+      * Read from the source. Moves the internal offset so that
+      * every call to read will return a new portion of the source.
+      * @param out the byte array to write the result to
+      * @param length the length of the byte array out
+      * @return the length in bytes that was actually read and put
+      * into out
+      */
+      virtual u32bit read(byte out[], u32bit length) = 0;
+
+      /**
+      * Read from the source but do not modify the internal offset. Consecutive
+      * calls to peek() will return portions of the source starting at the same
+      * position.
+      * @param out the byte array to write the output to
+      * @param length the length of the byte array out
+      * @return the length in bytes that was actually read and put
+      * into out
+      */
+      virtual u32bit peek(byte out[], u32bit length,
+                          u32bit peek_offset) const = 0;
+
+      /**
+      * Test whether the source still has data that can be read.
+      * @return true if there is still data to read, false otherwise
+      */
+      virtual bool end_of_data() const = 0;
+      /**
+      * return the id of this data source
+      * @return the std::string representing the id of this data source
+      */
+      virtual std::string id() const { return ""; }
+
+      /**
+      * Read one byte.
+      * @param the byte to read to
+      * @return the length in bytes that was actually read and put
+      * into out
+      */
+      u32bit read_byte(byte& out);
+
+      /**
+      * Peek at one byte.
+      * @param the byte to read to
+      * @return the length in bytes that was actually read and put
+      * into out
+      */
+      u32bit peek_byte(byte& out) const;
+
+      /**
+      * Discard the next N bytes of the data
+      * @param N the number of bytes to discard
+      * @return the number of bytes actually discarded
+      */
+      u32bit discard_next(u32bit N);
+
+      DataSource() {}
+      virtual ~DataSource() {}
+   private:
+      DataSource& operator=(const DataSource&) { return (*this); }
+      DataSource(const DataSource&);
+   };
+
+/**
+* This class represents a Memory-Based DataSource
+*/
+class BOTAN_DLL DataSource_Memory : public DataSource
+   {
+   public:
+      u32bit read(byte[], u32bit);
+      u32bit peek(byte[], u32bit, u32bit) const;
+      bool end_of_data() const;
+
+      /**
+      * Construct a memory source that reads from a string
+      * @param in the string to read from
+      */
+      DataSource_Memory(const std::string& in);
+
+      /**
+      * Construct a memory source that reads from a byte array
+      * @param in the byte array to read from
+      * @param length the length of the byte array
+      */
+      DataSource_Memory(const byte in[], u32bit length);
+
+      /**
+      * Construct a memory source that reads from a MemoryRegion
+      * @param in the MemoryRegion to read from
+      */
+      DataSource_Memory(const MemoryRegion<byte>& in);
+   private:
+      SecureVector<byte> source;
+      u32bit offset;
+   };
+
+/**
+* This class represents a Stream-Based DataSource.
+*/
+class BOTAN_DLL DataSource_Stream : public DataSource
+   {
+   public:
+      u32bit read(byte[], u32bit);
+      u32bit peek(byte[], u32bit, u32bit) const;
+      bool end_of_data() const;
+      std::string id() const;
+
+      DataSource_Stream(std::istream&, const std::string& id = "");
+
+      /**
+      * Construct a Stream-Based DataSource from file
+      * @param file the name of the file
+      * @param use_binary whether to treat the file as binary or not
+      */
+      DataSource_Stream(const std::string& file, bool use_binary = false);
+
+      ~DataSource_Stream();
+   private:
+      const std::string identifier;
+      const bool owner;
+
+      std::istream* source;
+      u32bit total_read;
+   };
+
+}
+
+#endif
diff --git a/src/utils/exceptn.cpp b/src/utils/exceptn.cpp
new file mode 100644
index 000000000..29357afa5
--- /dev/null
+++ b/src/utils/exceptn.cpp
@@ -0,0 +1,60 @@
+/*************************************************
+* Exceptions Source File                         *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/exceptn.h>
+#include <botan/parsing.h>
+
+namespace Botan {
+
+/*************************************************
+* Constructor for Invalid_Key_Length             *
+*************************************************/
+Invalid_Key_Length::Invalid_Key_Length(const std::string& name, u32bit length)
+   {
+   set_msg(name + " cannot accept a key of length " + to_string(length));
+   }
+
+/*************************************************
+* Constructor for Invalid_Block_Size             *
+*************************************************/
+Invalid_Block_Size::Invalid_Block_Size(const std::string& mode,
+                                       const std::string& pad)
+   {
+   set_msg("Padding method " + pad + " cannot be used with " + mode);
+   }
+
+/*************************************************
+* Constructor for Invalid_IV_Length              *
+*************************************************/
+Invalid_IV_Length::Invalid_IV_Length(const std::string& mode, u32bit bad_len)
+   {
+   set_msg("IV length " + to_string(bad_len) + " is invalid for " + mode);
+   }
+
+/*************************************************
+* Constructor for Algorithm_Not_Found            *
+*************************************************/
+Algorithm_Not_Found::Algorithm_Not_Found(const std::string& name)
+   {
+   set_msg("Could not find any algorithm named \"" + name + "\"");
+   }
+
+/*************************************************
+* Constructor for Invalid_Algorithm_Name         *
+*************************************************/
+Invalid_Algorithm_Name::Invalid_Algorithm_Name(const std::string& name)
+   {
+   set_msg("Invalid algorithm name: " + name);
+   }
+
+/*************************************************
+* Constructor for Config_Error                   *
+*************************************************/
+Config_Error::Config_Error(const std::string& err, u32bit line)
+   {
+   set_msg("Config error at line " + to_string(line) + ": " + err);
+   }
+
+}
diff --git a/src/utils/exceptn.h b/src/utils/exceptn.h
new file mode 100644
index 000000000..3bfec2fd2
--- /dev/null
+++ b/src/utils/exceptn.h
@@ -0,0 +1,195 @@
+/*************************************************
+* Exceptions Header File                         *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#ifndef BOTAN_EXCEPTION_H__
+#define BOTAN_EXCEPTION_H__
+
+#include <botan/types.h>
+#include <exception>
+#include <string>
+
+namespace Botan {
+
+/*************************************************
+* Exception Base Class                           *
+*************************************************/
+class BOTAN_DLL Exception : public std::exception
+   {
+   public:
+      const char* what() const throw() { return msg.c_str(); }
+      Exception(const std::string& m = "Unknown error") { set_msg(m); }
+      virtual ~Exception() throw() {}
+   protected:
+      void set_msg(const std::string& m) { msg = "Botan: " + m; }
+   private:
+      std::string msg;
+   };
+
+/*************************************************
+* Invalid_Argument Exception                     *
+*************************************************/
+struct BOTAN_DLL Invalid_Argument : public Exception
+   {
+   Invalid_Argument(const std::string& err = "") : Exception(err) {}
+   };
+
+/*************************************************
+* Invalid_Key_Length Exception                   *
+*************************************************/
+struct BOTAN_DLL Invalid_Key_Length : public Invalid_Argument
+   {
+   Invalid_Key_Length(const std::string&, u32bit);
+   };
+
+/*************************************************
+* Invalid_Block_Size Exception                   *
+*************************************************/
+struct BOTAN_DLL Invalid_Block_Size : public Invalid_Argument
+   {
+   Invalid_Block_Size(const std::string&, const std::string&);
+   };
+
+/*************************************************
+* Invalid_IV_Length Exception                    *
+*************************************************/
+struct BOTAN_DLL Invalid_IV_Length : public Invalid_Argument
+   {
+   Invalid_IV_Length(const std::string&, u32bit);
+   };
+
+/*************************************************
+* Invalid_State Exception                        *
+*************************************************/
+struct BOTAN_DLL Invalid_State : public Exception
+   {
+   Invalid_State(const std::string& err) : Exception(err) {}
+   };
+
+/*************************************************
+* PRNG_Unseeded Exception                        *
+*************************************************/
+struct BOTAN_DLL PRNG_Unseeded : public Invalid_State
+   {
+   PRNG_Unseeded(const std::string& algo) :
+      Invalid_State("PRNG not seeded: " + algo) {}
+   };
+
+/*************************************************
+* Policy_Violation Exception                     *
+*************************************************/
+struct BOTAN_DLL Policy_Violation : public Invalid_State
+   {
+   Policy_Violation(const std::string& err) :
+      Invalid_State("Policy violation: " + err) {}
+   };
+
+/*************************************************
+* Lookup_Error Exception                         *
+*************************************************/
+struct BOTAN_DLL Lookup_Error : public Exception
+   {
+   Lookup_Error(const std::string& err) : Exception(err) {}
+   };
+
+/*************************************************
+* Algorithm_Not_Found Exception                  *
+*************************************************/
+struct BOTAN_DLL Algorithm_Not_Found : public Exception
+   {
+   Algorithm_Not_Found(const std::string&);
+   };
+
+/*************************************************
+* Format_Error Exception                         *
+*************************************************/
+struct BOTAN_DLL Format_Error : public Exception
+   {
+   Format_Error(const std::string& err = "") : Exception(err) {}
+   };
+
+/*************************************************
+* Invalid_Algorithm_Name Exception               *
+*************************************************/
+struct BOTAN_DLL Invalid_Algorithm_Name : public Format_Error
+   {
+   Invalid_Algorithm_Name(const std::string&);
+   };
+
+/*************************************************
+* Encoding_Error Exception                       *
+*************************************************/
+struct BOTAN_DLL Encoding_Error : public Format_Error
+   {
+   Encoding_Error(const std::string& name) :
+      Format_Error("Encoding error: " + name) {}
+   };
+
+/*************************************************
+* Decoding_Error Exception                       *
+*************************************************/
+struct BOTAN_DLL Decoding_Error : public Format_Error
+   {
+   Decoding_Error(const std::string& name) :
+      Format_Error("Decoding error: " + name) {}
+   };
+
+/*************************************************
+* Invalid_OID Exception                          *
+*************************************************/
+struct BOTAN_DLL Invalid_OID : public Decoding_Error
+   {
+   Invalid_OID(const std::string& oid) :
+      Decoding_Error("Invalid ASN.1 OID: " + oid) {}
+   };
+
+/*************************************************
+* Stream_IO_Error Exception                      *
+*************************************************/
+struct BOTAN_DLL Stream_IO_Error : public Exception
+   {
+   Stream_IO_Error(const std::string& err) :
+      Exception("I/O error: " + err) {}
+   };
+
+/*************************************************
+* Configuration Error Exception                  *
+*************************************************/
+struct BOTAN_DLL Config_Error : public Format_Error
+   {
+   Config_Error(const std::string& err) :
+      Format_Error("Config error: " + err) {}
+   Config_Error(const std::string&, u32bit);
+   };
+
+/*************************************************
+* Integrity Failure Exception                    *
+*************************************************/
+struct BOTAN_DLL Integrity_Failure : public Exception
+   {
+   Integrity_Failure(const std::string& err) :
+      Exception("Integrity failure: " + err) {}
+   };
+
+/*************************************************
+* Internal_Error Exception                       *
+*************************************************/
+struct BOTAN_DLL Internal_Error : public Exception
+   {
+   Internal_Error(const std::string& err) :
+      Exception("Internal error: " + err) {}
+   };
+
+/*************************************************
+* Self Test Failure Exception                    *
+*************************************************/
+struct BOTAN_DLL Self_Test_Failure : public Internal_Error
+   {
+   Self_Test_Failure(const std::string& err) :
+      Internal_Error("Self test failed: " + err) {}
+   };
+
+}
+
+#endif
diff --git a/src/utils/info.txt b/src/utils/info.txt
index 127ea5e2f..4999a08e7 100644
--- a/src/utils/info.txt
+++ b/src/utils/info.txt
@@ -15,12 +15,17 @@ filters
 <add>
 bit_ops.h
 bswap.h
+buf_comp.h
 charset.cpp
 charset.h
+data_src.cpp
+data_src.h
 datastor.cpp
 datastor.h
-entropy.h
 entropy.cpp
+entropy.h
+exceptn.cpp
+exceptn.h
 loadstor.h
 mem_ops.h
 mlock.cpp
@@ -28,6 +33,7 @@ mutex.h
 parsing.cpp
 parsing.h
 rotate.h
+secmem.h
 stl_util.h
 types.h
 ui.cpp
diff --git a/src/utils/secmem.h b/src/utils/secmem.h
new file mode 100644
index 000000000..8e353a68b
--- /dev/null
+++ b/src/utils/secmem.h
@@ -0,0 +1,435 @@
+/*************************************************
+* Secure Memory Buffers Header File              *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#ifndef BOTAN_SECURE_MEMORY_BUFFERS_H__
+#define BOTAN_SECURE_MEMORY_BUFFERS_H__
+
+#include <botan/allocate.h>
+#include <botan/mem_ops.h>
+
+namespace Botan {
+
+/**
+* This class represents variable length memory buffers.
+*/
+template<typename T>
+class MemoryRegion
+   {
+   public:
+      /**
+      * Find out the size of the buffer, i.e. how many objects of type T it
+      * contains.
+      * @return the size of the buffer
+      */
+      u32bit size() const { return used; }
+
+      /**
+      * Find out whether this buffer is empty.
+      * @return true if the buffer is empty, false otherwise
+      */
+      bool is_empty() const { return (used == 0); }
+
+      /**
+      * Find out whether this buffer is non-empty
+      * @return true if the buffer is non-empty, false otherwise
+      */
+      bool has_items() const { return (used != 0); }
+
+      /**
+      * Get a pointer to the first element in the buffer.
+      * @return a pointer to the first element in the buffer
+      */
+      operator T* () { return buf; }
+
+      /**
+      * Get a constant pointer to the first element in the buffer.
+      * @return a constant pointer to the first element in the buffer
+      */
+      operator const T* () const { return buf; }
+
+      /**
+      * Get a pointer to the first element in the buffer.
+      * @return a pointer to the first element in the buffer
+      */
+      T* begin() { return buf; }
+
+      /**
+      * Get a constant pointer to the first element in the buffer.
+      * @return a constant pointer to the first element in the buffer
+      */
+      const T* begin() const { return buf; }
+
+      /**
+      * Get a pointer to the last element in the buffer.
+      * @return a pointer to the last element in the buffer
+      */
+      T* end() { return (buf + size()); }
+
+      /**
+      * Get a constant pointer to the last element in the buffer.
+      * @return a constant pointer to the last element in the buffer
+      */
+      const T* end() const { return (buf + size()); }
+
+      /**
+      * Check two buffers for equality.
+      * @return true iff the content of both buffers is byte-wise equal
+      */
+      bool operator==(const MemoryRegion<T>& other) const
+         {
+         return (size() == other.size() &&
+                 same_mem(buf, other.buf, size()));
+         }
+
+      /**
+      * Compare two buffers lexicographically.
+      * @return true if this buffer is lexicographically smaller than other.
+      */
+      bool operator<(const MemoryRegion<T>& other) const;
+
+      /**
+      * Check two buffers for inequality.
+      * @return false if the content of both buffers is byte-wise equal, true
+      * otherwise.
+      */
+      bool operator!=(const MemoryRegion<T>& in) const
+         { return (!(*this == in)); }
+
+      /**
+      * Copy the contents of another buffer into this buffer.
+      * The former contents of *this are discarded.
+      * @param in the buffer to copy the contents from.
+      * @return a reference to *this
+      */
+      MemoryRegion<T>& operator=(const MemoryRegion<T>& in)
+         { if(this != &in) set(in); return (*this); }
+
+      /**
+      * The use of this function is discouraged because of the risk of memory
+      * errors. Use MemoryRegion<T>::set()
+      * instead.
+      * Copy the contents of an array of objects of type T into this buffer.
+      * The former contents of *this are discarded.
+      * The length of *this must be at least n, otherwise memory errors occur.
+      * @param in the array to copy the contents from
+      * @param n the length of in
+      */
+      void copy(const T in[], u32bit n)
+         { copy(0, in, n); }
+
+      /**
+      * The use of this function is discouraged because of the risk of memory
+      * errors. Use MemoryRegion<T>::set()
+      * instead.
+      * Copy the contents of an array of objects of type T into this buffer.
+      * The former contents of *this are discarded.
+      * The length of *this must be at least n, otherwise memory errors occur.
+      * @param off the offset position inside this buffer to start inserting
+      * the copied bytes
+      * @param in the array to copy the contents from
+      * @param n the length of in
+      */
+      void copy(u32bit off, const T in[], u32bit n)
+         { copy_mem(buf + off, in, (n > size() - off) ? (size() - off) : n); }
+
+      /**
+      * Set the contents of this according to the argument. The size of
+      * *this is increased if necessary.
+      * @param in the array of objects of type T to copy the contents from
+      * @param n the size of array in
+      */
+      void set(const T in[], u32bit n)    { create(n); copy(in, n); }
+
+      /**
+      * Set the contents of this according to the argument. The size of
+      * *this is increased if necessary.
+      * @param in the buffer to copy the contents from
+      */
+      void set(const MemoryRegion<T>& in) { set(in.begin(), in.size()); }
+
+      /**
+      * Append data to the end of this buffer.
+      * @param data the array containing the data to append
+      * @param n the size of the array data
+      */
+      void append(const T data[], u32bit n)
+         { grow_to(size()+n); copy(size() - n, data, n); }
+
+      /**
+      * Append a single element.
+      * @param x the element to append
+      */
+      void append(T x) { append(&x, 1); }
+
+      /**
+      * Append data to the end of this buffer.
+      * @param data the buffer containing the data to append
+      */
+      void append(const MemoryRegion<T>& x) { append(x.begin(), x.size()); }
+
+      /**
+      * Zeroise the bytes of this buffer. The length remains unchanged.
+      */
+      void clear() { clear_mem(buf, allocated); }
+
+      /**
+      * Reset this buffer to an empty buffer with size zero.
+      */
+      void destroy() { create(0); }
+
+      /**
+      * Reset this buffer to a buffer of specified length. The content will be
+      * initialized to zero bytes.
+      * @param n the new length of the buffer
+      */
+      void create(u32bit n);
+
+      /**
+      * Preallocate memory, so that this buffer can grow up to size n without
+      * having to perform any actual memory allocations. (This is
+      * the same principle as for std::vector::reserve().)
+      */
+      void grow_to(u32bit N);
+
+      /**
+      * Swap this buffer with another object.
+      */
+      void swap(MemoryRegion<T>& other);
+
+      ~MemoryRegion() { deallocate(buf, allocated); }
+   protected:
+      MemoryRegion() { buf = 0; alloc = 0; used = allocated = 0; }
+      MemoryRegion(const MemoryRegion<T>& other)
+         {
+         buf = 0;
+         used = allocated = 0;
+         alloc = other.alloc;
+         set(other.buf, other.used);
+         }
+
+      void init(bool locking, u32bit length = 0)
+         { alloc = Allocator::get(locking); create(length); }
+   private:
+      T* allocate(u32bit n)
+         {
+         return static_cast<T*>(alloc->allocate(sizeof(T)*n));
+         }
+
+      void deallocate(T* p, u32bit n)
+         { alloc->deallocate(p, sizeof(T)*n); }
+
+      T* buf;
+      u32bit used;
+      u32bit allocated;
+      Allocator* alloc;
+   };
+
+/*************************************************
+* Create a new buffer                            *
+*************************************************/
+template<typename T>
+void MemoryRegion<T>::create(u32bit n)
+   {
+   if(n <= allocated) { clear(); used = n; return; }
+   deallocate(buf, allocated);
+   buf = allocate(n);
+   allocated = used = n;
+   }
+
+/*************************************************
+* Increase the size of the buffer                *
+*************************************************/
+template<typename T>
+void MemoryRegion<T>::grow_to(u32bit n)
+   {
+   if(n > used && n <= allocated)
+      {
+      clear_mem(buf + used, n - used);
+      used = n;
+      return;
+      }
+   else if(n > allocated)
+      {
+      T* new_buf = allocate(n);
+      copy_mem(new_buf, buf, used);
+      deallocate(buf, allocated);
+      buf = new_buf;
+      allocated = used = n;
+      }
+   }
+
+/*************************************************
+* Compare this buffer with another one           *
+*************************************************/
+template<typename T>
+bool MemoryRegion<T>::operator<(const MemoryRegion<T>& in) const
+   {
+   if(size() < in.size()) return true;
+   if(size() > in.size()) return false;
+
+   for(u32bit j = 0; j != size(); j++)
+      {
+      if(buf[j] < in[j]) return true;
+      if(buf[j] > in[j]) return false;
+      }
+
+   return false;
+   }
+
+/*************************************************
+* Swap this buffer with another one              *
+*************************************************/
+template<typename T>
+void MemoryRegion<T>::swap(MemoryRegion<T>& x)
+   {
+   std::swap(buf, x.buf);
+   std::swap(used, x.used);
+   std::swap(allocated, x.allocated);
+   std::swap(alloc, x.alloc);
+   }
+
+/**
+* This class represents variable length buffers that do not
+* make use of memory locking.
+*/
+template<typename T>
+class MemoryVector : public MemoryRegion<T>
+   {
+   public:
+      /**
+      * Copy the contents of another buffer into this buffer.
+      * @param in the buffer to copy the contents from
+      * @return a reference to *this
+      */
+      MemoryVector<T>& operator=(const MemoryRegion<T>& in)
+         { if(this != &in) set(in); return (*this); }
+
+      /**
+      * Create a buffer of the specified length.
+      * @param n the length of the buffer to create.
+      *
+      */
+      MemoryVector(u32bit n = 0) { MemoryRegion<T>::init(false, n); }
+
+      /**
+      * Create a buffer with the specified contents.
+      * @param in the array containing the data to be initially copied
+      * into the newly created buffer
+      * @param n the size of the arry in
+      */
+      MemoryVector(const T in[], u32bit n)
+         { MemoryRegion<T>::init(false); set(in, n); }
+
+      /**
+      * Copy constructor.
+      */
+      MemoryVector(const MemoryRegion<T>& in)
+         { MemoryRegion<T>::init(false); set(in); }
+
+      /**
+      * Create a buffer whose content is the concatenation of two other
+      * buffers.
+      * @param in1 the first part of the new contents
+      * @param in2 the contents to be appended to in1
+      */
+      MemoryVector(const MemoryRegion<T>& in1, const MemoryRegion<T>& in2)
+         { MemoryRegion<T>::init(false); set(in1); append(in2); }
+   };
+
+/**
+* This class represents variable length buffers using the operating
+* systems capability to lock memory, i.e. keeping it from being
+* swapped out to disk. In this way, a security hole allowing attackers
+* to find swapped out secret keys is closed. Please refer to
+* Botan::InitializerOptions::secure_memory() for restrictions and
+* further details.
+*/
+template<typename T>
+class SecureVector : public MemoryRegion<T>
+   {
+   public:
+      /**
+      * Copy the contents of another buffer into this buffer.
+      * @param in the buffer to copy the contents from
+      * @return a reference to *this
+      */
+      SecureVector<T>& operator=(const MemoryRegion<T>& in)
+         { if(this != &in) set(in); return (*this); }
+
+      /**
+      * Create a buffer of the specified length.
+      * @param n the length of the buffer to create.
+      *
+      */
+      SecureVector(u32bit n = 0) { MemoryRegion<T>::init(true, n); }
+
+      /**
+      * Create a buffer with the specified contents.
+      * @param in the array containing the data to be initially copied
+      * into the newly created buffer
+      * @param n the size of the array in
+      */
+      SecureVector(const T in[], u32bit n)
+         { MemoryRegion<T>::init(true); set(in, n); }
+
+      /**
+      * Create a buffer with contents specified contents.
+      * @param in the buffer holding the contents that will be
+      * copied into the newly created buffer.
+      */
+      SecureVector(const MemoryRegion<T>& in)
+         { MemoryRegion<T>::init(true); set(in); }
+
+      /**
+      * Create a buffer whose content is the concatenation of two other
+      * buffers.
+      * @param in1 the first part of the new contents
+      * @param in2 the contents to be appended to in1
+      */
+      SecureVector(const MemoryRegion<T>& in1, const MemoryRegion<T>& in2)
+         { MemoryRegion<T>::init(true); set(in1); append(in2); }
+   };
+
+/**
+* This class represents fixed length buffers using the operating
+* systems capability to lock memory, i.e. keeping it from being
+* swapped out to disk. In this way, a security hole allowing attackers
+* to find swapped out secret keys is closed. Please refer to
+* Botan::InitializerOptions::secure_memory() for restrictions and
+* further details.
+*/
+template<typename T, u32bit L>
+class SecureBuffer : public MemoryRegion<T>
+   {
+   public:
+      /**
+      * Copy the contents of another buffer into this buffer.
+      * @param in the buffer to copy the contents from
+      * @return a reference to *this
+      */
+      SecureBuffer<T,L>& operator=(const SecureBuffer<T,L>& in)
+         { if(this != &in) set(in); return (*this); }
+
+      /**
+      * Create a buffer of the length L.
+      */
+      SecureBuffer() { MemoryRegion<T>::init(true, L); }
+
+      /**
+      * Create a buffer of size L with the specified contents.
+      * @param in the array containing the data to be initially copied
+      * into the newly created buffer
+      * @param n the size of the array in
+      */
+      SecureBuffer(const T in[], u32bit n)
+         { MemoryRegion<T>::init(true, L); copy(in, n); }
+   private:
+      SecureBuffer<T, L>& operator=(const MemoryRegion<T>& in)
+         { if(this != &in) set(in); return (*this); }
+   };
+
+}
+
+#endif