Merge pull request #844 from antonio-nino-diaz-arm/an/no-timingsafe

Revert "tbbr: Use constant-time bcmp() to compare hashes"

drivers/auth/mbedtls/mbedtls_crypto.c

@@ -217,7 +217,7 @@ static int verify_hash(void *data_ptr, unsigned int data_len,
 	}
 
 	/* Compare values */
-	rc = timingsafe_bcmp(data_hash, hash, mbedtls_md_get_size(md_info));
+	rc = memcmp(data_hash, hash, mbedtls_md_get_size(md_info));
 	if (rc != 0) {
 		return CRYPTO_ERR_HASH;
 	}

drivers/auth/mbedtls/mbedtls_x509_parser.c

@@ -393,7 +393,7 @@ static int cert_parse(void *img, unsigned int img_len)
 	if (sig_alg1.len != sig_alg2.len) {
 		return IMG_PARSER_ERR_FORMAT;
 	}
-	if (0 != timingsafe_bcmp(sig_alg1.p, sig_alg2.p, sig_alg1.len)) {
+	if (0 != memcmp(sig_alg1.p, sig_alg2.p, sig_alg1.len)) {
 		return IMG_PARSER_ERR_FORMAT;
 	}
 	memcpy(&sig_alg, &sig_alg1, sizeof(sig_alg));