diff --git a/serpent-decrypt.c b/serpent-decrypt.c
index 4ca7ffcdd8941b4cce4489ac7b77ad644fe9996b..7af429644c0de70220d2bf86d1ae59cbe1f5a852 100644
--- a/serpent-decrypt.c
+++ b/serpent-decrypt.c
@@ -198,52 +198,108 @@
y2 ^= x2; \
} while (0)
+/* S3 inverse: 0 9 10 7 11 14 6 13 3 5 12 2 4 8 15 1 */
+/* Original single-assignment form:
+ t01 = x2 | x3;
+ t02 = x0 | x3;
+ t03 = x2 ^ t02;
+ t04 = x1 ^ t02;
+ t05 = x0 ^ x3;
+ t06 = t04 & t03;
+ t07 = x1 & t01;
+ y2 = t05 ^ t06;
+ t09 = x0 ^ t03;
+ y0 = t07 ^ t03;
+ t11 = y0 | t05;
+ t12 = t09 & t11;
+ t13 = x0 & y2;
+ t14 = t01 ^ t05;
+ y1 = x1 ^ t12;
+ t16 = x1 | t13;
+ y3 = t14 ^ t16;
+*/
#define SBOX3_INVERSE(type, x0, x1, x2, x3, y0, y1, y2, y3) \
- do { \
- type t02, t03, t04, t05, t06, t07, t09; \
- type t11, t12, t13, t14, t16, t01; \
- t01 = x2 | x3; \
- t02 = x0 | x3; \
- t03 = x2 ^ t02; \
- t04 = x1 ^ t02; \
- t05 = x0 ^ x3; \
- t06 = t04 & t03; \
- t07 = x1 & t01; \
- y2 = t05 ^ t06; \
- t09 = x0 ^ t03; \
- y0 = t07 ^ t03; \
- t11 = y0 | t05; \
- t12 = t09 & t11; \
- t13 = x0 & y2; \
- t14 = t01 ^ t05; \
- y1 = x1 ^ t12; \
- t16 = x1 | t13; \
- y3 = t14 ^ t16; \
+ do { \
+ y3 = x2 | x3; \
+ y0 = x1 & y3; \
+ y2 = x0 | x3; \
+ y1 = x2 ^ y2; \
+ y0 ^= y1; \
+ x3 ^= x0; \
+ y3 ^= x3; \
+ y2 ^= x1; \
+ y2 &= y1; \
+ y2 ^= x3; \
+ y1 ^= x0; \
+ x3 |= y0; \
+ y1 &= x3; \
+ y1 ^= x1; \
+ x0 &= y2; \
+ x0 |= x1; \
+ y3 ^= x0; \
} while (0)
+/* S4 inverse: 5 0 8 3 10 9 7 14 2 12 11 6 4 15 13 1 */
+/* Original single-assignment form:
+ t01 = x1 | x3;
+ t02 = x2 | x3;
+ t03 = x0 & t01;
+ t04 = x1 ^ t02;
+ t05 = x2 ^ x3;
+ t06 = ~ t03;
+ t07 = x0 & t04;
+ y1 = t05 ^ t07;
+ t09 = y1 | t06;
+ t10 = x0 ^ t07;
+ t11 = t01 ^ t09;
+ t12 = x3 ^ t04;
+ t13 = x2 | t10;
+ y3 = t03 ^ t12;
+ t15 = x0 ^ t04;
+ y2 = t11 ^ t13;
+ y0 = t15 ^ t09;
+*/
#define SBOX4_INVERSE(type, x0, x1, x2, x3, y0, y1, y2, y3) \
- do { \
- type t02, t03, t04, t05, t06, t07, t09; \
- type t10, t11, t12, t13, t15, t01; \
- t01 = x1 | x3; \
- t02 = x2 | x3; \
- t03 = x0 & t01; \
- t04 = x1 ^ t02; \
- t05 = x2 ^ x3; \
- t06 = ~ t03; \
- t07 = x0 & t04; \
- y1 = t05 ^ t07; \
- t09 = y1 | t06; \
- t10 = x0 ^ t07; \
- t11 = t01 ^ t09; \
- t12 = x3 ^ t04; \
- t13 = x2 | t10; \
- y3 = t03 ^ t12; \
- t15 = x0 ^ t04; \
- y2 = t11 ^ t13; \
- y0 = t15 ^ t09; \
+ do { \
+ y1 = x2 ^ x3; \
+ y2 = x2 | x3; \
+ y2 ^= x1; \
+ x1 |= x3; \
+ y0 = x0 ^ y2; \
+ x3 ^= y2; \
+ y2 &= x0; \
+ y1 ^= y2; \
+ y2 ^= x0; \
+ y2 |= x2; \
+ x0 &= x1; \
+ y3 = x0 ^ x3; \
+ x0 = ~ x0; \
+ x0 |= y1; \
+ y0 ^= x0; \
+ x0 ^= x1; \
+ y2 ^= x0; \
} while (0)
+/* S5 inverse: 8 15 2 9 4 1 13 14 11 6 5 3 7 12 10 0 */
+/* Original single-assignment form:
+ t01 = x0 & x3;
+ t02 = x2 ^ t01;
+ t03 = x0 ^ x3;
+ t04 = x1 & t02;
+ t05 = x0 & x2;
+ y0 = t03 ^ t04;
+ t07 = x0 & y0;
+ t08 = t01 ^ y0;
+ t09 = x1 | t05;
+ t10 = ~ x1;
+ y1 = t08 ^ t09;
+ t12 = t10 | t07;
+ t13 = y0 | y1;
+ y3 = t02 ^ t12;
+ t15 = t02 ^ t13;
+ t16 = x1 ^ x3;
+ y2 = t16 ^ t15;
+*/
#define SBOX5_INVERSE(type, x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
type t02, t03, t04, t05, t07, t08, t09; \
@@ -267,6 +323,28 @@
y2 = t16 ^ t15; \
} while (0)
+/* S6 inverse: 15 10 1 13 5 3 6 0 4 9 14 7 2 12 8 11 */
+/* Original single-assignment form:
+ t01 = x0 ^ x2;
+ t02 = ~ x2;
+ t03 = x1 & t01;
+ t04 = x1 | t02;
+ t05 = x3 | t03;
+ t06 = x1 ^ x3;
+ t07 = x0 & t04;
+ t08 = x0 | t02;
+ t09 = t07 ^ t05;
+ y1 = t06 ^ t08;
+ y0 = ~ t09;
+ t12 = x1 & y0;
+ t13 = t01 & t05;
+ t14 = t01 ^ t12;
+ t15 = t07 ^ t13;
+ t16 = x3 | t02;
+ t17 = x0 ^ y1;
+ y3 = t17 ^ t15;
+ y2 = t16 ^ t14;
+ */
#define SBOX6_INVERSE(type, x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
type t02, t03, t04, t05, t06, t07, t08, t09; \
@@ -292,6 +370,27 @@
y2 = t16 ^ t14; \
} while (0)
+/* S7 inverse: 3 0 6 13 9 14 15 8 5 12 11 7 10 1 4 2 */
+/* Original single-assignment form:
+ t01 = x0 & x1;
+ t02 = x0 | x1;
+ t03 = x2 | t01;
+ t04 = x3 & t02;
+ y3 = t03 ^ t04;
+ t06 = x1 ^ t04;
+ t07 = x3 ^ y3;
+ t08 = ~ t07;
+ t09 = t06 | t08;
+ t10 = x1 ^ x3;
+ t11 = x0 | x3;
+ y1 = x0 ^ t09;
+ t13 = x2 ^ t06;
+ t14 = x2 & t11;
+ t15 = x3 | y1;
+ t16 = t01 | t10;
+ y0 = t13 ^ t15;
+ y2 = t14 ^ t16;
+*/
#define SBOX7_INVERSE(type, x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
type t02, t03, t04, t06, t07, t08, t09; \