Extraction des multiplications hors de tweakey.c

De  façon à  ce  que  d'autres versions  puissent  réutiliser l'un  ou
l'autre.

4 files changed, 119 insertions, 91 deletions

diff --git a/src/ref/constants.h b/src/ref/constants.h
index 6812fd8..d2da2a0 100644
--- a/src/ref/constants.h
+++ b/src/ref/constants.h
@@ -23,6 +23,7 @@ This file provides bit and byte lengths for input and output parameters.
 #include "parameters.h"
 
 #define TWEAKEY_LENGTH_BITS       (TWEAK_LENGTH_BITS+KEY_LENGTH_BITS)
+#define LANE_BITS                 64
 #define ROUND_TWEAKEY_LENGTH_BITS 64
 #define BLOCK_LENGTH_BITS         128
 #define NONCE_LENGTH_BITS         120
@@ -31,6 +32,7 @@ This file provides bit and byte lengths for input and output parameters.
 #define TWEAK_BYTES         (TWEAK_LENGTH_BITS/8)
 #define KEY_BYTES           (KEY_LENGTH_BITS/8)
 #define TWEAKEY_BYTES       (TWEAKEY_LENGTH_BITS/8)
+#define LANE_BYTES          (LANE_BITS/8)
 #define ROUND_TWEAKEY_BYTES (ROUND_TWEAKEY_LENGTH_BITS/8)
 #define BLOCK_BYTES         (BLOCK_LENGTH_BITS/8)
 #define NONCE_BYTES         (NONCE_LENGTH_BITS/8)
diff --git a/src/ref/implem.mk b/src/ref/implem.mk
index f396696..a29b452 100644
--- a/src/ref/implem.mk
+++ b/src/ref/implem.mk
@@ -26,7 +26,7 @@ $(src_dir)/lilliput-ae.h $(src_dir)/cipher.h $(src_dir)/constants.h
 $(variant_dir)/parameters.h
 
 $(results_dir)/$(src_dir)/tweakey.o: $(src_dir)/tweakey.h       \
-$(src_dir)/constants.h $(variant_dir)/parameters.h
+$(src_dir)/constants.h $(src_dir)/multiplications.h $(variant_dir)/parameters.h
 
 $(results_dir)/test/test-tbc-encrypt.o $(results_dir)/test/test-tbc-decrypt.o $(results_dir)/test/traces-tbc.o: \
 $(src_dir)/cipher.h
diff --git a/src/ref/multiplications.h b/src/ref/multiplications.h
new file mode 100644
index 0000000..32327f2
--- /dev/null
+++ b/src/ref/multiplications.h
@@ -0,0 +1,114 @@
+/*
+Implementation of the Lilliput-AE tweakable block cipher.
+
+Authors, hereby denoted as "the implementer":
+    Kévin Le Gouguec,
+    2019.
+
+For more information, feedback or questions, refer to our website:
+https://paclido.fr/lilliput-ae
+
+To the extent possible under law, the implementer has waived all copyright
+and related or neighboring rights to the source code in this file.
+http://creativecommons.org/publicdomain/zero/1.0/
+
+---
+
+This file implements the alpha-multiplications used in Lilliput-TBC's
+tweakey schedule, where each matrix M and M_R to the power n are
+implemented in distinct functions with shifts and XORs.
+*/
+
+#ifndef MULTIPLICATIONS_H
+#define MULTIPLICATIONS_H
+
+#include <stdint.h>
+
+#include "constants.h"
+
+static void _multiply_M(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
+{
+    y[7] = x[6];
+    y[6] = x[5];
+    y[5] = x[5]<<3 ^ x[4];
+    y[4] = x[4]>>3 ^ x[3];
+    y[3] = x[2];
+    y[2] = x[6]<<2 ^ x[1];
+    y[1] = x[0];
+    y[0] = x[7];
+}
+
+static void _multiply_M2(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
+{
+    uint8_t x_M_5 = x[5]<<3 ^ x[4];
+    uint8_t x_M_4 = x[4]>>3 ^ x[3];
+
+    y[7] = x[5];
+    y[6] = x_M_5;
+    y[5] = x_M_5<<3 ^ x_M_4;
+    y[4] = x_M_4>>3 ^ x[2];
+    y[3] = x[6]<<2  ^ x[1];
+    y[2] = x[5]<<2  ^ x[0];
+    y[1] = x[7];
+    y[0] = x[6];
+}
+
+static void _multiply_M3(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
+{
+    uint8_t x_M_5  = x[5]<<3  ^ x[4];
+    uint8_t x_M_4  = x[4]>>3  ^ x[3];
+    uint8_t x_M2_5 = x_M_5<<3 ^ x_M_4;
+    uint8_t x_M2_4 = x_M_4>>3 ^ x[2];
+
+    y[7] = x_M_5;
+    y[6] = x_M2_5;
+    y[5] = x_M2_5<<3 ^ x_M2_4;
+    y[4] = x_M2_4>>3 ^ x[6]<<2 ^ x[1];
+    y[3] = x[5]<<2   ^ x[0];
+    y[2] = x_M_5<<2  ^ x[7];
+    y[1] = x[6];
+    y[0] = x[5];
+}
+
+static void _multiply_MR(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
+{
+    y[0] = x[1];
+    y[1] = x[2];
+    y[2] = x[3]    ^ x[4]>>3;
+    y[3] = x[4];
+    y[4] = x[5]    ^ x[6]<<3;
+    y[5] = x[3]<<2 ^ x[6];
+    y[6] = x[7];
+    y[7] = x[0];
+}
+
+static void _multiply_MR2(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
+{
+    uint8_t x_MR_4 = x[5] ^ x[6]<<3;
+
+    y[0] = x[2];
+    y[1] = x[3]    ^ x[4]>>3;
+    y[2] = x[4]    ^ x_MR_4>>3;
+    y[3] = x_MR_4;
+    y[4] = x[3]<<2 ^ x[6]      ^ x[7]<<3;
+    y[5] = x[4]<<2 ^ x[7];
+    y[6] = x[0];
+    y[7] = x[1];
+}
+
+static void _multiply_MR3(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
+{
+    uint8_t x_MR_4  = x[5]    ^ x[6]<<3;
+    uint8_t x_MR2_4 = x[3]<<2 ^ x[6]    ^ x[7]<<3;
+
+    y[0] = x[3]      ^ x[4]>>3;
+    y[1] = x[4]      ^ x_MR_4>>3;
+    y[2] = x_MR_4    ^ x_MR2_4>>3;
+    y[3] = x_MR2_4;
+    y[4] = x[0]<<3   ^ x[4]<<2   ^ x[7];
+    y[5] = x_MR_4<<2 ^ x[0];
+    y[6] = x[1];
+    y[7] = x[2];
+}
+
+#endif /* MULTIPLICATIONS_H */
diff --git a/src/ref/tweakey.c b/src/ref/tweakey.c
index 78c6060..bae09d3 100644
--- a/src/ref/tweakey.c
+++ b/src/ref/tweakey.c
@@ -14,20 +14,17 @@ http://creativecommons.org/publicdomain/zero/1.0/
 
 ---
 
-This file provides an implementation of Lilliput-TBC's tweakey schedule,
-where multiplications by matrices M and M_R to the power n are performed
-by functions expressing the exponentiated matrices with shifts and XORs.
+This file provides the implementation of Lilliput-TBC's tweakey schedule.
 */
 
 #include <stdint.h>
 #include <string.h>
 
 #include "constants.h"
+#include "multiplications.h"
 #include "tweakey.h"
 
 
-#define LANE_BITS  64
-#define LANE_BYTES (LANE_BITS/8)
 #define LANES_NB   (TWEAKEY_BYTES/LANE_BYTES)
 
 
@@ -64,91 +61,6 @@ void tweakey_state_extract(
 }
 
 
-static void _multiply_M(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
-{
-    y[7] = x[6];
-    y[6] = x[5];
-    y[5] = x[5]<<3 ^ x[4];
-    y[4] = x[4]>>3 ^ x[3];
-    y[3] = x[2];
-    y[2] = x[6]<<2 ^ x[1];
-    y[1] = x[0];
-    y[0] = x[7];
-}
-
-static void _multiply_M2(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
-{
-    uint8_t x_M_5 = x[5]<<3 ^ x[4];
-    uint8_t x_M_4 = x[4]>>3 ^ x[3];
-
-    y[7] = x[5];
-    y[6] = x_M_5;
-    y[5] = x_M_5<<3 ^ x_M_4;
-    y[4] = x_M_4>>3 ^ x[2];
-    y[3] = x[6]<<2  ^ x[1];
-    y[2] = x[5]<<2  ^ x[0];
-    y[1] = x[7];
-    y[0] = x[6];
-}
-
-static void _multiply_M3(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
-{
-    uint8_t x_M_5  = x[5]<<3  ^ x[4];
-    uint8_t x_M_4  = x[4]>>3  ^ x[3];
-    uint8_t x_M2_5 = x_M_5<<3 ^ x_M_4;
-    uint8_t x_M2_4 = x_M_4>>3 ^ x[2];
-
-    y[7] = x_M_5;
-    y[6] = x_M2_5;
-    y[5] = x_M2_5<<3 ^ x_M2_4;
-    y[4] = x_M2_4>>3 ^ x[6]<<2 ^ x[1];
-    y[3] = x[5]<<2   ^ x[0];
-    y[2] = x_M_5<<2  ^ x[7];
-    y[1] = x[6];
-    y[0] = x[5];
-}
-
-static void _multiply_MR(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
-{
-    y[0] = x[1];
-    y[1] = x[2];
-    y[2] = x[3]    ^ x[4]>>3;
-    y[3] = x[4];
-    y[4] = x[5]    ^ x[6]<<3;
-    y[5] = x[3]<<2 ^ x[6];
-    y[6] = x[7];
-    y[7] = x[0];
-}
-
-static void _multiply_MR2(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
-{
-    uint8_t x_MR_4 = x[5] ^ x[6]<<3;
-
-    y[0] = x[2];
-    y[1] = x[3]    ^ x[4]>>3;
-    y[2] = x[4]    ^ x_MR_4>>3;
-    y[3] = x_MR_4;
-    y[4] = x[3]<<2 ^ x[6]      ^ x[7]<<3;
-    y[5] = x[4]<<2 ^ x[7];
-    y[6] = x[0];
-    y[7] = x[1];
-}
-
-static void _multiply_MR3(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
-{
-    uint8_t x_MR_4  = x[5]    ^ x[6]<<3;
-    uint8_t x_MR2_4 = x[3]<<2 ^ x[6]    ^ x[7]<<3;
-
-    y[0] = x[3]      ^ x[4]>>3;
-    y[1] = x[4]      ^ x_MR_4>>3;
-    y[2] = x_MR_4    ^ x_MR2_4>>3;
-    y[3] = x_MR2_4;
-    y[4] = x[0]<<3   ^ x[4]<<2   ^ x[7];
-    y[5] = x_MR_4<<2 ^ x[0];
-    y[6] = x[1];
-    y[7] = x[2];
-}
-
 typedef void (*matrix_multiplication)(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES]);
 
 static const matrix_multiplication ALPHAS[6] = {