diff options
| author | lloyd <[email protected]> | 2010-08-19 05:50:31 +0000 |
|---|---|---|
| committer | lloyd <[email protected]> | 2010-08-19 05:50:31 +0000 |
| commit | df4b36149bbec56a74cb824494fe5eb7ccf335c8 (patch) | |
| tree | 97320391141ce4c270d9a2c511fc242177bc82b9 | |
| parent | 02620c3c59e0773ba9a89035dd6ebe33127aba16 (diff) | |
Also use a smaller table in the first round of AES in the decrypt direction
| -rw-r--r-- | src/block/aes/aes.cpp | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/src/block/aes/aes.cpp b/src/block/aes/aes.cpp index 1177a1461..54a663045 100644 --- a/src/block/aes/aes.cpp +++ b/src/block/aes/aes.cpp @@ -539,15 +539,25 @@ void AES::decrypt_n(const byte in[], byte out[], u32bit blocks) const u32bit T2 = load_be<u32bit>(in, 2) ^ DK[2]; u32bit T3 = load_be<u32bit>(in, 3) ^ DK[3]; - u32bit B0, B1, B2, B3; - B0 = TD0[get_byte(0, T0)] ^ TD1[get_byte(1, T3)] ^ - TD2[get_byte(2, T2)] ^ TD3[get_byte(3, T1)] ^ DK[4]; - B1 = TD0[get_byte(0, T1)] ^ TD1[get_byte(1, T0)] ^ - TD2[get_byte(2, T3)] ^ TD3[get_byte(3, T2)] ^ DK[5]; - B2 = TD0[get_byte(0, T2)] ^ TD1[get_byte(1, T1)] ^ - TD2[get_byte(2, T0)] ^ TD3[get_byte(3, T3)] ^ DK[6]; - B3 = TD0[get_byte(0, T3)] ^ TD1[get_byte(1, T2)] ^ - TD2[get_byte(2, T1)] ^ TD3[get_byte(3, T0)] ^ DK[7]; + u32bit B0 = TD[get_byte(0, T0)] ^ + rotate_right(TD[get_byte(1, T3)], 8) ^ + rotate_right(TD[get_byte(2, T2)], 16) ^ + rotate_right(TD[get_byte(3, T1)], 24) ^ DK[4]; + + u32bit B1 = TD[get_byte(0, T1)] ^ + rotate_right(TD[get_byte(1, T0)], 8) ^ + rotate_right(TD[get_byte(2, T3)], 16) ^ + rotate_right(TD[get_byte(3, T2)], 24) ^ DK[5]; + + u32bit B2 = TD[get_byte(0, T2)] ^ + rotate_right(TD[get_byte(1, T1)], 8) ^ + rotate_right(TD[get_byte(2, T0)], 16) ^ + rotate_right(TD[get_byte(3, T3)], 24) ^ DK[6]; + + u32bit B3 = TD[get_byte(0, T3)] ^ + rotate_right(TD[get_byte(1, T2)], 8) ^ + rotate_right(TD[get_byte(2, T1)], 16) ^ + rotate_right(TD[get_byte(3, T0)], 24) ^ DK[7]; for(u32bit j = 2; j != ROUNDS; j += 2) { |