1 files changed, 105 insertions, 0 deletions
diff --git a/botan/src/hash/mdx_hash/mdx_hash.cpp b/botan/src/hash/mdx_hash/mdx_hash.cpp
new file mode 100644
index 0000000..b630ec2
--- /dev/null
+++ b/botan/src/hash/mdx_hash/mdx_hash.cpp
@@ -0,0 +1,105 @@
+/**
+* Merkle-Damgard Hash Function
+* (C) 1999-2008 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/mdx_hash.h>
+#include <botan/exceptn.h>
+#include <botan/loadstor.h>
+
+namespace Botan {
+
+/**
+* MDx_HashFunction Constructor
+*/
+MDx_HashFunction::MDx_HashFunction(u32bit hash_len, u32bit block_len,
+                                   bool byte_end, bool bit_end,
+                                   u32bit cnt_size) :
+   HashFunction(hash_len, block_len), buffer(block_len),
+   BIG_BYTE_ENDIAN(byte_end), BIG_BIT_ENDIAN(bit_end), COUNT_SIZE(cnt_size)
+   {
+   if(COUNT_SIZE >= OUTPUT_LENGTH || COUNT_SIZE >= HASH_BLOCK_SIZE)
+      throw Invalid_Argument("MDx_HashFunction: COUNT_SIZE is too big");
+   count = position = 0;
+   }
+
+/**
+* Clear memory of sensitive data
+*/
+void MDx_HashFunction::clear() throw()
+   {
+   buffer.clear();
+   count = position = 0;
+   }
+
+/**
+* Update the hash
+*/
+void MDx_HashFunction::add_data(const byte input[], u32bit length)
+   {
+   count += length;
+
+   if(position)
+      {
+      buffer.copy(position, input, length);
+
+      if(position + length >= HASH_BLOCK_SIZE)
+         {
+         compress_n(buffer.begin(), 1);
+         input += (HASH_BLOCK_SIZE - position);
+         length -= (HASH_BLOCK_SIZE - position);
+         position = 0;
+         }
+      }
+
+   const u32bit full_blocks = length / HASH_BLOCK_SIZE;
+   const u32bit remaining   = length % HASH_BLOCK_SIZE;
+
+   if(full_blocks)
+      compress_n(input, full_blocks);
+
+   buffer.copy(position, input + full_blocks * HASH_BLOCK_SIZE, remaining);
+   position += remaining;
+   }
+
+/**
+* Finalize a hash
+*/
+void MDx_HashFunction::final_result(byte output[])
+   {
+   buffer[position] = (BIG_BIT_ENDIAN ? 0x80 : 0x01);
+   for(u32bit j = position+1; j != HASH_BLOCK_SIZE; ++j)
+      buffer[j] = 0;
+
+   if(position >= HASH_BLOCK_SIZE - COUNT_SIZE)
+      {
+      compress_n(buffer, 1);
+      buffer.clear();
+      }
+
+   write_count(buffer + HASH_BLOCK_SIZE - COUNT_SIZE);
+
+   compress_n(buffer, 1);
+   copy_out(output);
+   clear();
+   }
+
+/**
+* Write the count bits to the buffer
+*/
+void MDx_HashFunction::write_count(byte out[])
+   {
+   if(COUNT_SIZE < 8)
+      throw Invalid_State("MDx_HashFunction::write_count: COUNT_SIZE < 8");
+
+   const u64bit bit_count = count * 8;
+
+   if(BIG_BYTE_ENDIAN)
+      store_be(bit_count, out + COUNT_SIZE - 8);
+   else
+      store_le(bit_count, out + COUNT_SIZE - 8);
+   }
+
+}