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, 77 insertions, 65 deletions

diff --git a/src/block/mars/mars.cpp b/src/block/mars/mars.cpp
index 08c8409c5..69556acb3 100644
--- a/src/block/mars/mars.cpp
+++ b/src/block/mars/mars.cpp
@@ -1,6 +1,6 @@
 /*
 * MARS
-* (C) 1999-2007 Jack Lloyd
+* (C) 1999-2009 Jack Lloyd
 *
 * Distributed under the terms of the Botan license
 */
@@ -50,75 +50,87 @@ u32bit gen_mask(u32bit input)
 /*
 * MARS Encryption
 */
-void MARS::enc(const byte in[], byte out[]) const
+void MARS::encrypt_n(const byte in[], byte out[], u32bit blocks) const
    {
-   u32bit A = load_le<u32bit>(in, 0) + EK[0];
-   u32bit B = load_le<u32bit>(in, 1) + EK[1];
-   u32bit C = load_le<u32bit>(in, 2) + EK[2];
-   u32bit D = load_le<u32bit>(in, 3) + EK[3];
-
-   forward_mix(A, B, C, D);
-
-   encrypt_round(A, B, C, D,  0);
-   encrypt_round(B, C, D, A,  1);
-   encrypt_round(C, D, A, B,  2);
-   encrypt_round(D, A, B, C,  3);
-   encrypt_round(A, B, C, D,  4);
-   encrypt_round(B, C, D, A,  5);
-   encrypt_round(C, D, A, B,  6);
-   encrypt_round(D, A, B, C,  7);
-
-   encrypt_round(A, D, C, B,  8);
-   encrypt_round(B, A, D, C,  9);
-   encrypt_round(C, B, A, D, 10);
-   encrypt_round(D, C, B, A, 11);
-   encrypt_round(A, D, C, B, 12);
-   encrypt_round(B, A, D, C, 13);
-   encrypt_round(C, B, A, D, 14);
-   encrypt_round(D, C, B, A, 15);
-
-   reverse_mix(A, B, C, D);
-
-   A -= EK[36]; B -= EK[37]; C -= EK[38]; D -= EK[39];
-
-   store_le(out, A, B, C, D);
+   for(u32bit i = 0; i != blocks; ++i)
+      {
+      u32bit A = load_le<u32bit>(in, 0) + EK[0];
+      u32bit B = load_le<u32bit>(in, 1) + EK[1];
+      u32bit C = load_le<u32bit>(in, 2) + EK[2];
+      u32bit D = load_le<u32bit>(in, 3) + EK[3];
+
+      forward_mix(A, B, C, D);
+
+      encrypt_round(A, B, C, D,  0);
+      encrypt_round(B, C, D, A,  1);
+      encrypt_round(C, D, A, B,  2);
+      encrypt_round(D, A, B, C,  3);
+      encrypt_round(A, B, C, D,  4);
+      encrypt_round(B, C, D, A,  5);
+      encrypt_round(C, D, A, B,  6);
+      encrypt_round(D, A, B, C,  7);
+
+      encrypt_round(A, D, C, B,  8);
+      encrypt_round(B, A, D, C,  9);
+      encrypt_round(C, B, A, D, 10);
+      encrypt_round(D, C, B, A, 11);
+      encrypt_round(A, D, C, B, 12);
+      encrypt_round(B, A, D, C, 13);
+      encrypt_round(C, B, A, D, 14);
+      encrypt_round(D, C, B, A, 15);
+
+      reverse_mix(A, B, C, D);
+
+      A -= EK[36]; B -= EK[37]; C -= EK[38]; D -= EK[39];
+
+      store_le(out, A, B, C, D);
+
+      in += BLOCK_SIZE;
+      out += BLOCK_SIZE;
+      }
    }
 
 /*
 * MARS Decryption
 */
-void MARS::dec(const byte in[], byte out[]) const
+void MARS::decrypt_n(const byte in[], byte out[], u32bit blocks) const
    {
-   u32bit A = load_le<u32bit>(in, 3) + EK[39];
-   u32bit B = load_le<u32bit>(in, 2) + EK[38];
-   u32bit C = load_le<u32bit>(in, 1) + EK[37];
-   u32bit D = load_le<u32bit>(in, 0) + EK[36];
-
-   forward_mix(A, B, C, D);
-
-   decrypt_round(A, B, C, D, 15);
-   decrypt_round(B, C, D, A, 14);
-   decrypt_round(C, D, A, B, 13);
-   decrypt_round(D, A, B, C, 12);
-   decrypt_round(A, B, C, D, 11);
-   decrypt_round(B, C, D, A, 10);
-   decrypt_round(C, D, A, B,  9);
-   decrypt_round(D, A, B, C,  8);
-
-   decrypt_round(A, D, C, B,  7);
-   decrypt_round(B, A, D, C,  6);
-   decrypt_round(C, B, A, D,  5);
-   decrypt_round(D, C, B, A,  4);
-   decrypt_round(A, D, C, B,  3);
-   decrypt_round(B, A, D, C,  2);
-   decrypt_round(C, B, A, D,  1);
-   decrypt_round(D, C, B, A,  0);
-
-   reverse_mix(A, B, C, D);
-
-   A -= EK[3]; B -= EK[2]; C -= EK[1]; D -= EK[0];
-
-   store_le(out, D, C, B, A);
+   for(u32bit i = 0; i != blocks; ++i)
+      {
+      u32bit A = load_le<u32bit>(in, 3) + EK[39];
+      u32bit B = load_le<u32bit>(in, 2) + EK[38];
+      u32bit C = load_le<u32bit>(in, 1) + EK[37];
+      u32bit D = load_le<u32bit>(in, 0) + EK[36];
+
+      forward_mix(A, B, C, D);
+
+      decrypt_round(A, B, C, D, 15);
+      decrypt_round(B, C, D, A, 14);
+      decrypt_round(C, D, A, B, 13);
+      decrypt_round(D, A, B, C, 12);
+      decrypt_round(A, B, C, D, 11);
+      decrypt_round(B, C, D, A, 10);
+      decrypt_round(C, D, A, B,  9);
+      decrypt_round(D, A, B, C,  8);
+
+      decrypt_round(A, D, C, B,  7);
+      decrypt_round(B, A, D, C,  6);
+      decrypt_round(C, B, A, D,  5);
+      decrypt_round(D, C, B, A,  4);
+      decrypt_round(A, D, C, B,  3);
+      decrypt_round(B, A, D, C,  2);
+      decrypt_round(C, B, A, D,  1);
+      decrypt_round(D, C, B, A,  0);
+
+      reverse_mix(A, B, C, D);
+
+      A -= EK[3]; B -= EK[2]; C -= EK[1]; D -= EK[0];
+
+      store_le(out, D, C, B, A);
+
+      in += BLOCK_SIZE;
+      out += BLOCK_SIZE;
+      }
    }
 
 /*
diff --git a/src/block/mars/mars.h b/src/block/mars/mars.h
index ca49695af..b3d74b179 100644
--- a/src/block/mars/mars.h
+++ b/src/block/mars/mars.h
@@ -20,8 +20,8 @@ class BOTAN_DLL MARS : public BlockCipher
       BlockCipher* clone() const { return new MARS; }
       MARS() : BlockCipher(16, 16, 32, 4) {}
    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);
 
       void encrypt_round(u32bit&, u32bit&, u32bit&, u32bit&, u32bit) const;