Use mbedtls_xor in ccm
@@ -112,7 +112,6 @@ static int mbedtls_ccm_crypt( mbedtls_ccm_context *ctx,
const unsigned char *input,
unsigned char *output )
{
- size_t i;
size_t olen = 0;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char tmp_buf[16] = {0};
@@ -125,8 +124,7 @@ static int mbedtls_ccm_crypt( mbedtls_ccm_context *ctx,
return ret;
}
- for( i = 0; i < use_len; i++ )
- output[i] = input[i] ^ tmp_buf[offset + i];
+ mbedtls_xor( output, input, tmp_buf + offset, use_len );
mbedtls_platform_zeroize(tmp_buf, sizeof(tmp_buf));
return ret;
@@ -269,7 +267,6 @@ int mbedtls_ccm_update_ad( mbedtls_ccm_context *ctx,
size_t add_len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- unsigned char i;
size_t olen, use_len, offset;
if( ctx->state & CCM_STATE__ERROR )
@@ -310,8 +307,7 @@ int mbedtls_ccm_update_ad( mbedtls_ccm_context *ctx,
if( use_len > add_len )
use_len = add_len;
- for( i = 0; i < use_len; i++ )
- ctx->y[i + offset] ^= add[i];
+ mbedtls_xor( ctx->y + offset, ctx->y + offset, add, use_len );
ctx->processed += use_len;
add_len -= use_len;
@@ -381,8 +377,7 @@ int mbedtls_ccm_update( mbedtls_ccm_context *ctx,
if( ctx->mode == MBEDTLS_CCM_ENCRYPT || \
ctx->mode == MBEDTLS_CCM_STAR_ENCRYPT )
{
- for( i = 0; i < use_len; i++ )
- ctx->y[i + offset] ^= input[i];
+ mbedtls_xor( ctx->y + offset, ctx->y + offset, input, use_len );
if( use_len + offset == 16 || ctx->processed == ctx->plaintext_len )
{
@@ -411,8 +406,7 @@ int mbedtls_ccm_update( mbedtls_ccm_context *ctx,
if( ret != 0 )
goto exit;
- for( i = 0; i < use_len; i++ )
- ctx->y[i + offset] ^= local_output[i];
+ mbedtls_xor( ctx->y + offset, ctx->y + offset, local_output, use_len );
memcpy( output, local_output, use_len );
mbedtls_platform_zeroize( local_output, 16 );
