crypto: camellia - simplify key setup and CAMELLIA_ROUNDSM macro

camellia_setup_tail() applies 'inverse of the last half of P-function' to
subkeys, which is unneeded if keys are applied directly to yl/yr in
CAMELLIA_ROUNDSM.

Patch speeds up key setup and should speed up CAMELLIA_ROUNDSM as applying
key to yl/yr early has less register dependencies.

Quick tcrypt camellia results:
 x86_64, AMD Phenom II, ~5% faster
 x86_64, Intel Core 2, ~0.5% faster
 i386, Intel Atom N270, ~1% faster

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Jussi Kivilinna 2012-03-03 13:59:00 +02:00 committed by Herbert Xu
parent 8940426489
commit c9b56d33b0

View file

@ -382,7 +382,6 @@ static void camellia_setup_tail(u32 *subkey, u32 *subL, u32 *subR, int max)
{
u32 dw, tl, tr;
u32 kw4l, kw4r;
int i;
/* absorb kw2 to other subkeys */
/* round 2 */
@ -557,24 +556,6 @@ static void camellia_setup_tail(u32 *subkey, u32 *subL, u32 *subR, int max)
SUBKEY_L(32) = subL[32] ^ subL[31]; /* kw3 */
SUBKEY_R(32) = subR[32] ^ subR[31];
}
/* apply the inverse of the last half of P-function */
i = 2;
do {
dw = SUBKEY_L(i + 0) ^ SUBKEY_R(i + 0); dw = rol32(dw, 8);/* round 1 */
SUBKEY_R(i + 0) = SUBKEY_L(i + 0) ^ dw; SUBKEY_L(i + 0) = dw;
dw = SUBKEY_L(i + 1) ^ SUBKEY_R(i + 1); dw = rol32(dw, 8);/* round 2 */
SUBKEY_R(i + 1) = SUBKEY_L(i + 1) ^ dw; SUBKEY_L(i + 1) = dw;
dw = SUBKEY_L(i + 2) ^ SUBKEY_R(i + 2); dw = rol32(dw, 8);/* round 3 */
SUBKEY_R(i + 2) = SUBKEY_L(i + 2) ^ dw; SUBKEY_L(i + 2) = dw;
dw = SUBKEY_L(i + 3) ^ SUBKEY_R(i + 3); dw = rol32(dw, 8);/* round 4 */
SUBKEY_R(i + 3) = SUBKEY_L(i + 3) ^ dw; SUBKEY_L(i + 3) = dw;
dw = SUBKEY_L(i + 4) ^ SUBKEY_R(i + 4); dw = rol32(dw, 8);/* round 5 */
SUBKEY_R(i + 4) = SUBKEY_L(i + 4) ^ dw; SUBKEY_L(i + 4) = dw;
dw = SUBKEY_L(i + 5) ^ SUBKEY_R(i + 5); dw = rol32(dw, 8);/* round 6 */
SUBKEY_R(i + 5) = SUBKEY_L(i + 5) ^ dw; SUBKEY_L(i + 5) = dw;
i += 8;
} while (i < max);
}
static void camellia_setup128(const unsigned char *key, u32 *subkey)
@ -869,6 +850,8 @@ static void camellia_setup192(const unsigned char *key, u32 *subkey)
#define CAMELLIA_ROUNDSM(xl, xr, kl, kr, yl, yr, il, ir) \
do { \
yl ^= kl; \
yr ^= kr; \
ir = camellia_sp1110[(u8)xr]; \
il = camellia_sp1110[ (xl >> 24)]; \
ir ^= camellia_sp0222[ (xr >> 24)]; \
@ -877,8 +860,7 @@ static void camellia_setup192(const unsigned char *key, u32 *subkey)
il ^= camellia_sp3033[(u8)(xl >> 8)]; \
ir ^= camellia_sp4404[(u8)(xr >> 8)]; \
il ^= camellia_sp4404[(u8)xl]; \
il ^= kl; \
ir ^= il ^ kr; \
ir ^= il; \
yl ^= ir; \
yr ^= ror32(il, 8) ^ ir; \
} while (0)