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aria: move conditional outside of loop

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Manuel Pégourié-Gonnard 2018-02-21 09:50:17 +01:00
parent 9cc89248fe
commit c76ceb677b
1 changed files with 6 additions and 7 deletions
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13
library/aria.c
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@ -291,7 +291,7 @@ static void aria_fe_xor(uint32_t r[4],
r[3] = d ^ x[3];
}
// Big endian 128-bit rotation: d = a ^ (b <<< n), used only in key setup.
// Big endian 128-bit rotation: r = a ^ (b <<< n), used only in key setup.
// This is relatively slow since our implementation is geared towards
// little-endian targets and stores state in that order.
@ -301,18 +301,17 @@ static void aria_rot128(uint32_t r[4], const uint32_t a[4],
uint8_t i, j;
uint32_t t, u;
const uint8_t n1 = n & 0x1F; // bit offset
const uint8_t n2 = 32 - n1; // reverse bit offset
const uint8_t n1 = n % 32; // bit offset
const uint8_t n2 = n1 ? 32 - n1 : 0; // reverse bit offset
j = (n >> 5) & 3; // initial word offset
j = (n / 32) % 4; // initial word offset
t = ARIA_FLIP1( ARIA_FLIP2( b[j] ) ); // big endian
for( i = 0; i < 4; i++ )
{
j = (j + 1) & 3; // get next word, big endian
j = (j + 1) % 4; // get next word, big endian
u = ARIA_FLIP1( ARIA_FLIP2( b[j] ) );
t <<= n1; // rotate
if (n2 < 32) // rotate 32 bits = 0 bits..
t |= u >> n2;
t |= u >> n2;
t = ARIA_FLIP1( ARIA_FLIP2( t ) ); // back to little endian
r[i] = a[i] ^ t; // store
t = u; // move to next word