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.

2 files changed, 36 insertions, 24 deletions

diff --git a/src/block/lion/lion.cpp b/src/block/lion/lion.cpp
index c7cdf6d13..bfff64b67 100644
--- a/src/block/lion/lion.cpp
+++ b/src/block/lion/lion.cpp
@@ -14,41 +14,53 @@ namespace Botan {
 /*
 * Lion Encryption
 */
-void Lion::enc(const byte in[], byte out[]) const
+void Lion::encrypt_n(const byte in[], byte out[], u32bit blocks) const
    {
-   SecureVector<byte> buffer(LEFT_SIZE);
+   for(u32bit i = 0; i != blocks; ++i)
+      {
+      SecureVector<byte> buffer(LEFT_SIZE);
 
-   xor_buf(buffer, in, key1, LEFT_SIZE);
-   cipher->set_key(buffer, LEFT_SIZE);
-   cipher->encrypt(in + LEFT_SIZE, out + LEFT_SIZE, RIGHT_SIZE);
+      xor_buf(buffer, in, key1, LEFT_SIZE);
+      cipher->set_key(buffer, LEFT_SIZE);
+      cipher->encrypt(in + LEFT_SIZE, out + LEFT_SIZE, RIGHT_SIZE);
 
-   hash->update(out + LEFT_SIZE, RIGHT_SIZE);
-   hash->final(buffer);
-   xor_buf(out, in, buffer, LEFT_SIZE);
+      hash->update(out + LEFT_SIZE, RIGHT_SIZE);
+      hash->final(buffer);
+      xor_buf(out, in, buffer, LEFT_SIZE);
 
-   xor_buf(buffer, out, key2, LEFT_SIZE);
-   cipher->set_key(buffer, LEFT_SIZE);
-   cipher->encrypt(out + LEFT_SIZE, RIGHT_SIZE);
+      xor_buf(buffer, out, key2, LEFT_SIZE);
+      cipher->set_key(buffer, LEFT_SIZE);
+      cipher->encrypt(out + LEFT_SIZE, RIGHT_SIZE);
+
+      in += BLOCK_SIZE;
+      out += BLOCK_SIZE;
+      }
    }
 
 /*
 * Lion Decryption
 */
-void Lion::dec(const byte in[], byte out[]) const
+void Lion::decrypt_n(const byte in[], byte out[], u32bit blocks) const
    {
-   SecureVector<byte> buffer(LEFT_SIZE);
+   for(u32bit i = 0; i != blocks; ++i)
+      {
+      SecureVector<byte> buffer(LEFT_SIZE);
+
+      xor_buf(buffer, in, key2, LEFT_SIZE);
+      cipher->set_key(buffer, LEFT_SIZE);
+      cipher->encrypt(in + LEFT_SIZE, out + LEFT_SIZE, RIGHT_SIZE);
 
-   xor_buf(buffer, in, key2, LEFT_SIZE);
-   cipher->set_key(buffer, LEFT_SIZE);
-   cipher->encrypt(in + LEFT_SIZE, out + LEFT_SIZE, RIGHT_SIZE);
+      hash->update(out + LEFT_SIZE, RIGHT_SIZE);
+      hash->final(buffer);
+      xor_buf(out, in, buffer, LEFT_SIZE);
 
-   hash->update(out + LEFT_SIZE, RIGHT_SIZE);
-   hash->final(buffer);
-   xor_buf(out, in, buffer, LEFT_SIZE);
+      xor_buf(buffer, out, key1, LEFT_SIZE);
+      cipher->set_key(buffer, LEFT_SIZE);
+      cipher->encrypt(out + LEFT_SIZE, RIGHT_SIZE);
 
-   xor_buf(buffer, out, key1, LEFT_SIZE);
-   cipher->set_key(buffer, LEFT_SIZE);
-   cipher->encrypt(out + LEFT_SIZE, RIGHT_SIZE);
+      in += BLOCK_SIZE;
+      out += BLOCK_SIZE;
+      }
    }
 
 /*
diff --git a/src/block/lion/lion.h b/src/block/lion/lion.h
index 5bc4e72c0..d9f933846 100644
--- a/src/block/lion/lion.h
+++ b/src/block/lion/lion.h
@@ -27,8 +27,8 @@ class BOTAN_DLL Lion : public BlockCipher
       Lion(HashFunction*, StreamCipher*, u32bit);
       ~Lion() { delete hash; delete cipher; }
    private:
-      void enc(const byte[], byte[]) const;
-      void dec(const byte[], byte[]) const;
+      void encrypt_n(const byte in[], byte out[], u32bit blocks) const;
+      void decrypt_n(const byte in[], byte out[], u32bit blocks) const;
       void key_schedule(const byte[], u32bit);
 
       const u32bit LEFT_SIZE, RIGHT_SIZE;