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Merge pull request #8908 from daverodgman/cmac-perf

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CMAC size and perf
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Dave Rodgman 2024-03-12 13:17:00 +00:00 committed by GitHub
commit e0ffb1d2e9
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1 changed files with 14 additions and 7 deletions
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21
library/cmac.c
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@ -56,22 +56,29 @@ static int cmac_multiply_by_u(unsigned char *output,
size_t blocksize)
{
const unsigned char R_128 = 0x87;
const unsigned char R_64 = 0x1B;
unsigned char R_n, mask;
unsigned char overflow = 0x00;
uint32_t overflow = 0x00;
int i;
if (blocksize == MBEDTLS_AES_BLOCK_SIZE) {
R_n = R_128;
} else if (blocksize == MBEDTLS_DES3_BLOCK_SIZE) {
}
#if defined(MBEDTLS_DES_C)
else if (blocksize == MBEDTLS_DES3_BLOCK_SIZE) {
const unsigned char R_64 = 0x1B;
R_n = R_64;
} else {
}
#endif
else {
return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
}
for (i = (int) blocksize - 1; i >= 0; i--) {
output[i] = input[i] << 1 | overflow;
overflow = input[i] >> 7;
for (i = (int) blocksize - 4; i >= 0; i -= 4) {
uint32_t i32 = MBEDTLS_GET_UINT32_BE(&input[i], 0);
uint32_t new_overflow = i32 >> 31;
i32 = (i32 << 1) | overflow;
MBEDTLS_PUT_UINT32_BE(i32, &output[i], 0);
overflow = new_overflow;
}
/* mask = ( input[0] >> 7 ) ? 0xff : 0x00