Change the BlockCipher interface to support multi-block encryption and

decryption. Currently only used for counter mode. Doesn't offer much
advantage as-is (though might help slightly, in terms of cache effects),
but allows for SIMD implementations to process multiple blocks in parallel
when possible. Particularly thinking here of Serpent; TEA/XTEA also seem
promising in this sense, as is Threefish once that is implemented as a
standalone block cipher.

1 files changed, 58 insertions, 46 deletions

diff --git a/src/block/lubyrack/lubyrack.cpp b/src/block/lubyrack/lubyrack.cpp
index a9d2b1db2..6ad64f2b0 100644
--- a/src/block/lubyrack/lubyrack.cpp
+++ b/src/block/lubyrack/lubyrack.cpp
@@ -13,59 +13,71 @@ namespace Botan {
 /*
 * Luby-Rackoff Encryption
 */
-void LubyRackoff::enc(const byte in[], byte out[]) const
+void LubyRackoff::encrypt_n(const byte in[], byte out[], u32bit blocks) const
    {
-   const u32bit len = hash->OUTPUT_LENGTH;
-
-   SecureVector<byte> buffer(len);
-   hash->update(K1);
-   hash->update(in, len);
-   hash->final(buffer);
-   xor_buf(out + len, in + len, buffer, len);
-
-   hash->update(K2);
-   hash->update(out + len, len);
-   hash->final(buffer);
-   xor_buf(out, in, buffer, len);
-
-   hash->update(K1);
-   hash->update(out, len);
-   hash->final(buffer);
-   xor_buf(out + len, buffer, len);
-
-   hash->update(K2);
-   hash->update(out + len, len);
-   hash->final(buffer);
-   xor_buf(out, buffer, len);
+   for(u32bit i = 0; i != blocks; ++i)
+      {
+      const u32bit len = hash->OUTPUT_LENGTH;
+
+      SecureVector<byte> buffer(len);
+      hash->update(K1);
+      hash->update(in, len);
+      hash->final(buffer);
+      xor_buf(out + len, in + len, buffer, len);
+
+      hash->update(K2);
+      hash->update(out + len, len);
+      hash->final(buffer);
+      xor_buf(out, in, buffer, len);
+
+      hash->update(K1);
+      hash->update(out, len);
+      hash->final(buffer);
+      xor_buf(out + len, buffer, len);
+
+      hash->update(K2);
+      hash->update(out + len, len);
+      hash->final(buffer);
+      xor_buf(out, buffer, len);
+
+      in += BLOCK_SIZE;
+      out += BLOCK_SIZE;
+      }
    }
 
 /*
 * Luby-Rackoff Decryption
 */
-void LubyRackoff::dec(const byte in[], byte out[]) const
+void LubyRackoff::decrypt_n(const byte in[], byte out[], u32bit blocks) const
    {
-   const u32bit len = hash->OUTPUT_LENGTH;
-
-   SecureVector<byte> buffer(len);
-   hash->update(K2);
-   hash->update(in + len, len);
-   hash->final(buffer);
-   xor_buf(out, in, buffer, len);
-
-   hash->update(K1);
-   hash->update(out, len);
-   hash->final(buffer);
-   xor_buf(out + len, in + len, buffer, len);
-
-   hash->update(K2);
-   hash->update(out + len, len);
-   hash->final(buffer);
-   xor_buf(out, buffer, len);
-
-   hash->update(K1);
-   hash->update(out, len);
-   hash->final(buffer);
-   xor_buf(out + len, buffer, len);
+   for(u32bit i = 0; i != blocks; ++i)
+      {
+      const u32bit len = hash->OUTPUT_LENGTH;
+
+      SecureVector<byte> buffer(len);
+      hash->update(K2);
+      hash->update(in + len, len);
+      hash->final(buffer);
+      xor_buf(out, in, buffer, len);
+
+      hash->update(K1);
+      hash->update(out, len);
+      hash->final(buffer);
+      xor_buf(out + len, in + len, buffer, len);
+
+      hash->update(K2);
+      hash->update(out + len, len);
+      hash->final(buffer);
+      xor_buf(out, buffer, len);
+
+      hash->update(K1);
+      hash->update(out, len);
+      hash->final(buffer);
+      xor_buf(out + len, buffer, len);
+
+      in += BLOCK_SIZE;
+      out += BLOCK_SIZE;
+      }
    }
 
 /*