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Store polynomial in a constant variable

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This commit is contained in:
Manuel Thalmann 2023-11-12 20:17:51 +01:00
parent b3c10424a4
commit ffe2b8ef9a
1 changed files with 3 additions and 1 deletions
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4
aes/aes.cpp
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@ -11,6 +11,8 @@ http://csrc.nist.gov/publications/fips/fips197/fips-197.pdf
*/ */
/* AES Constants */ /* AES Constants */
// AES polynomial
const uint16_t POLYNOMIAL = 0b100011011;
// forward sbox // forward sbox
const uint8_t SBOX[256] = { const uint8_t SBOX[256] = {
@ -103,7 +105,7 @@ uint8_t xtime(uint8_t a) {
uint8_t mask; uint8_t mask;
if (a & 0b10000000) { if (a & 0b10000000) {
mask = 0x1B; mask = POLYNOMIAL & 0xFF;
} }
else { else {
mask = 0x00; mask = 0x00;