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-rw-r--r--src/add_threshold/cipher.c307
l---------src/add_threshold/cipher.h1
l---------src/add_threshold/constants.h1
l---------src/add_threshold/lilliput-ae-utils.h1
l---------src/add_threshold/lilliput-ae.h1
l---------src/add_threshold/lilliput-i.c1
l---------src/add_threshold/lilliput-ii.c1
-rw-r--r--src/add_threshold/tweakey.c216
-rw-r--r--src/add_threshold/tweakey.h47
9 files changed, 576 insertions, 0 deletions
diff --git a/src/add_threshold/cipher.c b/src/add_threshold/cipher.c
new file mode 100644
index 0000000..911449d
--- /dev/null
+++ b/src/add_threshold/cipher.c
@@ -0,0 +1,307 @@
+/*
+Implementation of the Lilliput-AE tweakable block cipher.
+
+Authors:
+ Kévin Le Gouguec,
+ Léo Reynaud,
+ Alexandre Adomnicai, 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 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.
+*/
+
+#include <stdint.h>
+#include <string.h>
+#include <stdio.h>
+
+#include "cipher.h"
+#include "constants.h"
+#include "tweakey.h"
+
+
+enum permutation
+{
+ PERMUTATION_ENCRYPTION = 0, /* PI(i) */
+ PERMUTATION_DECRYPTION = 1, /* PI^-1(i) */
+ PERMUTATION_NONE
+};
+
+typedef enum permutation permutation;
+
+static const uint8_t PERMUTATIONS[2][BLOCK_BYTES] = {
+ [PERMUTATION_ENCRYPTION] = { 13, 9, 14, 8, 10, 11, 12, 15, 4, 5, 3, 1, 2, 6, 0, 7 },
+ [PERMUTATION_DECRYPTION] = { 14, 11, 12, 10, 8, 9, 13, 15, 3, 1, 4, 5, 6, 0, 2, 7 }
+};
+
+static const uint8_t F[16][16] = {
+ {0x0, 0x2, 0x0, 0x2, 0x2, 0x0, 0x2, 0x0, 0x0, 0x2, 0x0, 0x2, 0x2, 0x0, 0x2, 0x0},
+ {0x0, 0x2, 0x9, 0xb, 0x3, 0x1, 0xa, 0x8, 0xd, 0xf, 0x4, 0x6, 0xe, 0xc, 0x7, 0x5},
+ {0x0, 0xb, 0x0, 0xb, 0xb, 0x0, 0xb, 0x0, 0x1, 0xa, 0x1, 0xa, 0xa, 0x1, 0xa, 0x1},
+ {0x9, 0x2, 0x0, 0xb, 0x3, 0x8, 0xa, 0x1, 0x5, 0xe, 0xc, 0x7, 0xf, 0x4, 0x6, 0xd},
+ {0x1, 0x2, 0x8, 0xb, 0x3, 0x0, 0xa, 0x9, 0x9, 0xa, 0x0, 0x3, 0xb, 0x8, 0x2, 0x1},
+ {0x0, 0x3, 0x0, 0x3, 0x3, 0x0, 0x3, 0x0, 0x5, 0x6, 0x5, 0x6, 0x6, 0x5, 0x6, 0x5},
+ {0x8, 0x2, 0x1, 0xb, 0x3, 0x9, 0xa, 0x0, 0x1, 0xb, 0x8, 0x2, 0xa, 0x0, 0x3, 0x9},
+ {0x0, 0xa, 0x0, 0xa, 0xa, 0x0, 0xa, 0x0, 0x4, 0xe, 0x4, 0xe, 0xe, 0x4, 0xe, 0x4},
+ {0x1, 0xe, 0x0, 0xf, 0xb, 0x4, 0xa, 0x5, 0x1, 0xe, 0x0, 0xf, 0xb, 0x4, 0xa, 0x5},
+ {0xc, 0x3, 0x4, 0xb, 0x7, 0x8, 0xf, 0x0, 0x1, 0xe, 0x9, 0x6, 0xa, 0x5, 0x2, 0xd},
+ {0x0, 0x6, 0x1, 0x7, 0x3, 0x5, 0x2, 0x4, 0x1, 0x7, 0x0, 0x6, 0x2, 0x4, 0x3, 0x5},
+ {0x4, 0x2, 0xc, 0xa, 0x6, 0x0, 0xe, 0x8, 0x8, 0xe, 0x0, 0x6, 0xa, 0xc, 0x2, 0x4},
+ {0x8, 0x6, 0x0, 0xe, 0x2, 0xc, 0xa, 0x4, 0x0, 0xe, 0x8, 0x6, 0xa, 0x4, 0x2, 0xc},
+ {0x4, 0xa, 0x5, 0xb, 0xf, 0x1, 0xe, 0x0, 0x1, 0xf, 0x0, 0xe, 0xa, 0x4, 0xb, 0x5},
+ {0x0, 0x7, 0x8, 0xf, 0x3, 0x4, 0xb, 0xc, 0x9, 0xe, 0x1, 0x6, 0xa, 0xd, 0x2, 0x5},
+ {0x5, 0x2, 0x4, 0x3, 0x7, 0x0, 0x6, 0x1, 0x1, 0x6, 0x0, 0x7, 0x3, 0x4, 0x2, 0x5}
+};
+
+static const uint8_t G[4][16] = {
+ {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf},
+ {0x0, 0x1, 0x2, 0x3, 0x5, 0x4, 0x7, 0x6, 0x8, 0x9, 0xa, 0xb, 0xd, 0xc, 0xf, 0xe},
+ {0x0, 0x1, 0x3, 0x2, 0x4, 0x5, 0x7, 0x6, 0x8, 0x9, 0xb, 0xa, 0xc, 0xd, 0xf, 0xe},
+ {0x1, 0x0, 0x2, 0x3, 0x4, 0x5, 0x7, 0x6, 0x9, 0x8, 0xa, 0xb, 0xc, 0xd, 0xf, 0xe}
+};
+
+static const uint8_t Q[8][16] = {
+ {0x0, 0x4, 0x2, 0x6, 0x8, 0xc, 0xa, 0xe, 0x1, 0x5, 0x3, 0x7, 0x9, 0xd, 0xb, 0xf},
+ {0x0, 0x4, 0xa, 0xe, 0x8, 0xc, 0x2, 0x6, 0x3, 0x7, 0x9, 0xd, 0xb, 0xf, 0x1, 0x5},
+ {0x0, 0xc, 0x2, 0xe, 0x8, 0x4, 0xa, 0x6, 0x1, 0xd, 0x3, 0xf, 0x9, 0x5, 0xb, 0x7},
+ {0x8, 0x4, 0x2, 0xe, 0x0, 0xc, 0xa, 0x6, 0xb, 0x7, 0x1, 0xd, 0x3, 0xf, 0x9, 0x5},
+ {0x0, 0x6, 0x2, 0x4, 0x8, 0xe, 0xa, 0xc, 0x1, 0x7, 0x3, 0x5, 0x9, 0xf, 0xb, 0xd},
+ {0x2, 0x4, 0x8, 0xe, 0xa, 0xc, 0x0, 0x6, 0x1, 0x7, 0xb, 0xd, 0x9, 0xf, 0x3, 0x5},
+ {0x0, 0xe, 0x2, 0xc, 0x8, 0x6, 0xa, 0x4, 0x1, 0xf, 0x3, 0xd, 0x9, 0x7, 0xb, 0x5},
+ {0xa, 0x4, 0x0, 0xe, 0x2, 0xc, 0x8, 0x6, 0x9, 0x7, 0x3, 0xd, 0x1, 0xf, 0xb, 0x5}
+};
+
+static const uint8_t P[16] = {
+ 0x0, 0x2, 0x8, 0xa, 0x4, 0X6, 0xc, 0xe, 0x1, 0x3, 0x9, 0xb, 0x5, 0x7, 0xd, 0xf
+};
+
+static void _state_init_TI(uint8_t X[BLOCK_BYTES], uint8_t Y[BLOCK_BYTES], uint8_t Z[BLOCK_BYTES], const uint8_t message[BLOCK_BYTES])
+{
+ // To be replaced by real random numbers!!!
+ uint8_t SHARES_0[BLOCK_BYTES] = {
+ 0x0f, 0x1e, 0x2d, 0x3c, 0x4b, 0x5a, 0x69, 0x78, 0x87, 0x96, 0xa5, 0xb4, 0xc3, 0xd2, 0xe1, 0xf0
+ };
+ uint8_t SHARES_1[BLOCK_BYTES] = {
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
+ };
+
+ memcpy(X, SHARES_0, BLOCK_BYTES);
+ memcpy(Y, SHARES_1, BLOCK_BYTES);
+ for (uint8_t i=0; i<BLOCK_BYTES; i++)
+ {
+ Z[i] = message[i] ^ SHARES_0[i] ^ SHARES_1[i];
+ }
+}
+
+
+static void _compute_round_tweakeys_TI(
+ const uint8_t key[KEY_BYTES],
+ const uint8_t tweak[TWEAK_BYTES],
+ uint8_t RTK_X[ROUNDS][ROUND_TWEAKEY_BYTES],
+ uint8_t RTK_Y[ROUNDS][ROUND_TWEAKEY_BYTES]
+)
+{
+ uint8_t TK_X[TWEAKEY_BYTES];
+ uint8_t TK_Y[TWEAKEY_BYTES];
+ tweakey_state_init_TI(TK_X, TK_Y, key, tweak);
+ tweakey_state_extract_TI(TK_X, TK_Y, 0, RTK_X[0], RTK_Y[0]);
+
+ for (uint8_t i=1; i<ROUNDS; i++)
+ {
+ tweakey_state_update_TI(TK_X, TK_Y);
+ tweakey_state_extract_TI(TK_X, TK_Y, i, RTK_X[i], RTK_Y[i]);
+ }
+}
+
+
+static void _nonlinear_layer_TI(
+ uint8_t X[BLOCK_BYTES],
+ uint8_t Y[BLOCK_BYTES],
+ uint8_t Z[BLOCK_BYTES],
+ const uint8_t RTK_X[ROUND_TWEAKEY_BYTES],
+ const uint8_t RTK_Y[ROUND_TWEAKEY_BYTES]
+)
+{
+ uint8_t x_hi, y_hi, z_hi; // High nibbles for the Feistel network
+ uint8_t x_lo, y_lo, z_lo; // Low nibbles for the Feistel network
+ uint8_t tmp0, tmp1, tmp2;
+ uint8_t TMP_X[ROUND_TWEAKEY_BYTES];
+ uint8_t TMP_Y[ROUND_TWEAKEY_BYTES];
+ uint8_t TMP_Z[ROUND_TWEAKEY_BYTES];
+
+ // Apply the RTK to two shares
+ for (size_t j=0; j<ROUND_TWEAKEY_BYTES; j++)
+ {
+ TMP_X[j] = X[j] ^ RTK_X[j];
+ TMP_Y[j] = Y[j] ^ RTK_Y[j];
+ }
+
+ // Threshold Implementation of the 8-bit S-box
+ for (size_t j=0; j<ROUND_TWEAKEY_BYTES; j++)
+ {
+ // Decomposition into nibbles
+ x_hi = TMP_X[j] >> 4;
+ x_lo = TMP_X[j] & 0xf;
+ y_hi = TMP_Y[j] >> 4;
+ y_lo = TMP_Y[j] & 0xf;
+ z_hi = Z[j] >> 4;
+ z_lo = Z[j] & 0xf;
+ // First 4-bit S-box
+ tmp0 = G[(y_lo&7)>>1][z_lo];
+ tmp1 = G[(z_lo&7)>>1][x_lo];
+ tmp2 = G[(x_lo&7)>>1][y_lo];
+ x_hi ^= F[tmp1][tmp2];
+ y_hi ^= F[tmp2][tmp0];
+ z_hi ^= F[tmp0][tmp1];
+ // Second 4-bit S-box
+ tmp0 = P[Q[y_hi&3 ^ (y_hi&8)>>1][z_hi]];
+ tmp1 = P[Q[z_hi&3 ^ (z_hi&8)>>1][x_hi]];
+ tmp2 = P[Q[x_hi&3 ^ (x_hi&8)>>1][y_hi]];
+ x_lo ^= Q[tmp1&3 ^ (tmp1&8)>>1][tmp2];
+ y_lo ^= Q[tmp2&3 ^ (tmp2&8)>>1][tmp0];
+ z_lo ^= Q[tmp0&3 ^ (tmp0&8)>>1][tmp1];
+ // Third 4-bit S-box
+ tmp0 = G[(y_lo&7)>>1][z_lo] ^ 1;
+ tmp1 = G[(z_lo&7)>>1][x_lo];
+ tmp2 = G[(x_lo&7)>>1][y_lo];
+ x_hi ^= F[tmp1][tmp2];
+ y_hi ^= F[tmp2][tmp0];
+ z_hi ^= F[tmp0][tmp1];
+ // Build bytes from nibbles
+ TMP_X[j] = (x_hi << 4 | x_lo);
+ TMP_Y[j] = (y_hi << 4 | y_lo);
+ TMP_Z[j] = (z_hi << 4 | z_lo);
+ }
+
+ for (size_t j=0; j<8; j++)
+ {
+ size_t dest_j = 15-j;
+ X[dest_j] ^= TMP_X[j];
+ Y[dest_j] ^= TMP_Y[j];
+ Z[dest_j] ^= TMP_Z[j];
+ }
+}
+
+static void _linear_layer(uint8_t X[BLOCK_BYTES])
+{
+ X[15] ^= X[1];
+ X[15] ^= X[2];
+ X[15] ^= X[3];
+ X[15] ^= X[4];
+ X[15] ^= X[5];
+ X[15] ^= X[6];
+ X[15] ^= X[7];
+
+ X[14] ^= X[7];
+ X[13] ^= X[7];
+ X[12] ^= X[7];
+ X[11] ^= X[7];
+ X[10] ^= X[7];
+ X[9] ^= X[7];
+}
+
+static void _permutation_layer(uint8_t X[BLOCK_BYTES], permutation p)
+{
+ if (p == PERMUTATION_NONE)
+ {
+ return;
+ }
+
+ uint8_t X_old[BLOCK_BYTES];
+ memcpy(X_old, X, BLOCK_BYTES);
+
+ const uint8_t *pi = PERMUTATIONS[p];
+
+ for (size_t j=0; j<BLOCK_BYTES; j++)
+ {
+ X[pi[j]] = X_old[j];
+ }
+}
+
+static void _one_round_egfn_TI(
+ uint8_t X[BLOCK_BYTES],
+ uint8_t Y[BLOCK_BYTES],
+ uint8_t Z[BLOCK_BYTES],
+ const uint8_t RTK_X[ROUND_TWEAKEY_BYTES],
+ const uint8_t RTK_Y[ROUND_TWEAKEY_BYTES],
+ permutation p
+)
+{
+ _nonlinear_layer_TI(X, Y, Z, RTK_X, RTK_Y);
+ _linear_layer(X);
+ _linear_layer(Y);
+ _linear_layer(Z);
+ _permutation_layer(X, p);
+ _permutation_layer(Y, p);
+ _permutation_layer(Z, p);
+}
+
+
+void lilliput_tbc_encrypt(
+ const uint8_t key[KEY_BYTES],
+ const uint8_t tweak[TWEAK_BYTES],
+ const uint8_t message[BLOCK_BYTES],
+ uint8_t ciphertext[BLOCK_BYTES]
+)
+{
+ uint8_t X[BLOCK_BYTES];
+ uint8_t Y[BLOCK_BYTES];
+ uint8_t Z[BLOCK_BYTES];
+ _state_init_TI(X, Y, Z, message);
+
+ uint8_t RTK_X[ROUNDS][ROUND_TWEAKEY_BYTES];
+ uint8_t RTK_Y[ROUNDS][ROUND_TWEAKEY_BYTES];
+ _compute_round_tweakeys_TI(key, tweak, RTK_X, RTK_Y);
+
+
+ for (uint8_t i=0; i<ROUNDS-1; i++)
+ {
+ _one_round_egfn_TI(X, Y, Z, RTK_X[i], RTK_Y[i], PERMUTATION_ENCRYPTION);
+ }
+
+ _one_round_egfn_TI(X, Y, Z, RTK_X[ROUNDS-1], RTK_Y[ROUNDS-1], PERMUTATION_NONE);
+
+
+ for (size_t i=0; i<BLOCK_BYTES; i++)
+ {
+ ciphertext[i] = X[i] ^ Y[i] ^ Z[i];
+ }
+}
+
+void lilliput_tbc_decrypt(
+ const uint8_t key[KEY_BYTES],
+ const uint8_t tweak[TWEAK_BYTES],
+ const uint8_t ciphertext[BLOCK_BYTES],
+ uint8_t message[BLOCK_BYTES]
+)
+{
+ uint8_t X[BLOCK_BYTES];
+ uint8_t Y[BLOCK_BYTES];
+ uint8_t Z[BLOCK_BYTES];
+ _state_init_TI(X, Y, Z, ciphertext);
+
+ uint8_t RTK_X[ROUNDS][ROUND_TWEAKEY_BYTES];
+ uint8_t RTK_Y[ROUNDS][ROUND_TWEAKEY_BYTES];
+ _compute_round_tweakeys_TI(key, tweak, RTK_X, RTK_Y);
+
+ for (uint8_t i=0; i<ROUNDS-1; i++)
+ {
+ _one_round_egfn_TI(X, Y, Z, RTK_X[ROUNDS-1-i], RTK_Y[ROUNDS-1-i], PERMUTATION_DECRYPTION);
+ }
+
+ _one_round_egfn_TI(X, Y, Z, RTK_X[0], RTK_Y[0], PERMUTATION_NONE);
+
+ for (size_t i=0; i<BLOCK_BYTES; i++)
+ {
+ message[i] = X[i] ^ Y[i] ^ Z[i];
+ }
+}
diff --git a/src/add_threshold/cipher.h b/src/add_threshold/cipher.h
new file mode 120000
index 0000000..eab258b
--- /dev/null
+++ b/src/add_threshold/cipher.h
@@ -0,0 +1 @@
+../ref/cipher.h \ No newline at end of file
diff --git a/src/add_threshold/constants.h b/src/add_threshold/constants.h
new file mode 120000
index 0000000..67df0f3
--- /dev/null
+++ b/src/add_threshold/constants.h
@@ -0,0 +1 @@
+../ref/constants.h \ No newline at end of file
diff --git a/src/add_threshold/lilliput-ae-utils.h b/src/add_threshold/lilliput-ae-utils.h
new file mode 120000
index 0000000..b46625b
--- /dev/null
+++ b/src/add_threshold/lilliput-ae-utils.h
@@ -0,0 +1 @@
+../ref/lilliput-ae-utils.h \ No newline at end of file
diff --git a/src/add_threshold/lilliput-ae.h b/src/add_threshold/lilliput-ae.h
new file mode 120000
index 0000000..66c8314
--- /dev/null
+++ b/src/add_threshold/lilliput-ae.h
@@ -0,0 +1 @@
+../ref/lilliput-ae.h \ No newline at end of file
diff --git a/src/add_threshold/lilliput-i.c b/src/add_threshold/lilliput-i.c
new file mode 120000
index 0000000..46688d4
--- /dev/null
+++ b/src/add_threshold/lilliput-i.c
@@ -0,0 +1 @@
+../ref/lilliput-i.c \ No newline at end of file
diff --git a/src/add_threshold/lilliput-ii.c b/src/add_threshold/lilliput-ii.c
new file mode 120000
index 0000000..09abf10
--- /dev/null
+++ b/src/add_threshold/lilliput-ii.c
@@ -0,0 +1 @@
+../ref/lilliput-ii.c \ No newline at end of file
diff --git a/src/add_threshold/tweakey.c b/src/add_threshold/tweakey.c
new file mode 100644
index 0000000..28d0e3d
--- /dev/null
+++ b/src/add_threshold/tweakey.c
@@ -0,0 +1,216 @@
+/*
+Implementation of the Lilliput-AE tweakable block cipher.
+
+Authors:
+ Kévin Le Gouguec,
+ Léo Reynaud,
+ Alexandre Adomnicai, 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 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.
+*/
+
+#include <stdint.h>
+#include <string.h>
+
+#include "constants.h"
+#include "tweakey.h"
+
+
+#define LANE_BITS 64
+#define LANE_BYTES (LANE_BITS/8)
+#define LANES_NB (TWEAKEY_BYTES/LANE_BYTES)
+
+
+void tweakey_state_init_TI(
+ uint8_t TK_X[TWEAKEY_BYTES],
+ uint8_t TK_Y[KEY_BYTES],
+ const uint8_t key[KEY_BYTES],
+ const uint8_t tweak[TWEAK_BYTES]
+)
+{
+ // To be replaced by real random numbers!!!
+ uint8_t SHARES_0[KEY_BYTES] = {
+ 0x0f, 0x1e, 0x2d, 0x3c, 0x4b, 0x5a, 0x69, 0x78, 0x87, 0x96, 0xa5, 0xb4, 0xc3, 0xd2, 0xe1, 0xf0
+ };
+
+ memcpy(TK_Y, SHARES_0, KEY_BYTES);
+ memcpy(TK_X, tweak, TWEAK_BYTES);
+
+ for (size_t i=0; i<KEY_BYTES; i++){
+ TK_X[i+TWEAK_BYTES] = key[i] ^ SHARES_0[i] ;
+ }
+}
+
+
+void tweakey_state_extract_TI(
+ const uint8_t TK_X[TWEAKEY_BYTES],
+ const uint8_t TK_Y[KEY_BYTES],
+ uint8_t round_constant,
+ uint8_t round_tweakey_X[ROUND_TWEAKEY_BYTES],
+ uint8_t round_tweakey_Y[ROUND_TWEAKEY_BYTES]
+)
+{
+ memset(round_tweakey_X, 0, ROUND_TWEAKEY_BYTES);
+ memset(round_tweakey_Y, 0, ROUND_TWEAKEY_BYTES);
+
+ for (size_t j=0; j<LANES_NB; j++)
+ {
+ const uint8_t *TKj_X = TK_X + j*LANE_BYTES;
+
+ for (size_t k=0; k<LANE_BYTES; k++)
+ {
+ round_tweakey_X[k] ^= TKj_X[k];
+ }
+ }
+
+
+ for (size_t j=0; j<(KEY_BYTES / LANE_BYTES); j++)
+ {
+ const uint8_t *TKj_Y = TK_Y + j*LANE_BYTES;
+
+ for (size_t k=0; k<LANE_BYTES; k++)
+ {
+ round_tweakey_Y[k] ^= TKj_Y[k];
+ }
+ }
+
+ round_tweakey_X[0] ^= round_constant;
+}
+
+
+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] = {
+ _multiply_M,
+ _multiply_M2,
+ _multiply_M3,
+ _multiply_MR,
+ _multiply_MR2,
+ _multiply_MR3
+};
+
+
+void tweakey_state_update_TI(uint8_t TK_X[TWEAKEY_BYTES], uint8_t TK_Y[KEY_BYTES])
+{
+ /* Skip lane 0, as it is multiplied by the identity matrix. */
+
+ for (size_t j=1; j<(TWEAK_BYTES/LANE_BYTES); j++)
+ {
+ uint8_t *TKj_X = TK_X + j*LANE_BYTES;
+
+ uint8_t TKj_old_X[LANE_BYTES];
+ memcpy(TKj_old_X, TKj_X, LANE_BYTES);
+
+ ALPHAS[j-1](TKj_old_X, TKj_X);
+ }
+
+ for (size_t j=0; j<(KEY_BYTES/LANE_BYTES); j++)
+ {
+ uint8_t *TKj_X = TK_X + (j + (TWEAK_BYTES/LANE_BYTES))*LANE_BYTES;
+ uint8_t *TKj_Y = TK_Y + j*LANE_BYTES;
+
+ uint8_t TKj_X_old[LANE_BYTES];
+ uint8_t TKj_Y_old[LANE_BYTES];
+ memcpy(TKj_X_old, TKj_X, LANE_BYTES);
+ memcpy(TKj_Y_old, TKj_Y, LANE_BYTES);
+
+ ALPHAS[j-1 + (TWEAK_BYTES/LANE_BYTES)](TKj_X_old, TKj_X);
+ ALPHAS[j-1 + (TWEAK_BYTES/LANE_BYTES)](TKj_Y_old, TKj_Y);
+ }
+}
diff --git a/src/add_threshold/tweakey.h b/src/add_threshold/tweakey.h
new file mode 100644
index 0000000..c76d655
--- /dev/null
+++ b/src/add_threshold/tweakey.h
@@ -0,0 +1,47 @@
+/*
+Implementation of the Lilliput-AE tweakable block cipher.
+
+Authors:
+ Kévin Le Gouguec,
+ Léo Reynaud,
+ Alexandre Adomnicai, 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 provides the interface for Lilliput-TBC's tweakey schedule.
+*/
+
+#ifndef TWEAKEY_H
+#define TWEAKEY_H
+
+#include <stdint.h>
+
+#include "constants.h"
+
+
+void tweakey_state_init_TI(
+ uint8_t TK_X[TWEAKEY_BYTES],
+ uint8_t TK_Y[TWEAKEY_BYTES],
+ const uint8_t key[KEY_BYTES],
+ const uint8_t tweak[TWEAK_BYTES]
+);
+
+void tweakey_state_extract_TI(
+ const uint8_t TK_X[TWEAKEY_BYTES],
+ const uint8_t TK_Y[KEY_BYTES],
+ uint8_t round_constant,
+ uint8_t round_tweakey_X[ROUND_TWEAKEY_BYTES],
+ uint8_t round_tweakey_Y[ROUND_TWEAKEY_BYTES]
+);
+
+void tweakey_state_update_TI(uint8_t TK_X[TWEAKEY_BYTES], uint8_t TK_Y[KEY_BYTES]);
+
+
+#endif /* TWEAKEY_H */