Added more default backends (Azure#18614)

sdk/attestation/azure-security-attestation/tests/test_attestation_token.py

@@ -11,6 +11,7 @@
 from typing import Dict
 import unittest
 from cryptography import x509
+from cryptography.hazmat.backends import default_backend
 from cryptography.hazmat.primitives import hashes, serialization
 from cryptography.hazmat.primitives.asymmetric.dsa import DSAPublicKey
 from devtools_testutils import AzureTestCase, ResourceGroupPreparer, PowerShellPreparer
@@ -116,21 +117,21 @@ def callback(token, signer):
     # Helper functions to create keys and certificates wrapping those keys.
     @staticmethod
     def _create_ecds_key(): #type() -> EllipticCurvePrivateKey
-        return ec.generate_private_key(ec.SECP256R1()).private_bytes(
+        return ec.generate_private_key(ec.SECP256R1(), backend=default_backend()).private_bytes(
             serialization.Encoding.DER,
             serialization.PrivateFormat.PKCS8,
             serialization.NoEncryption())
 
     @staticmethod
     def _create_rsa_key(): #type() -> EllipticCurvePrivateKey
-        return rsa.generate_private_key(65537, 2048).private_bytes(
+        return rsa.generate_private_key(65537, 2048, backend=default_backend()).private_bytes(
             serialization.Encoding.DER,
             serialization.PrivateFormat.PKCS8,
             serialization.NoEncryption())
 
     @staticmethod
     def _create_x509_certificate(key_der, subject_name): #type(Union[EllipticCurvePrivateKey,RSAPrivateKey], str) -> Certificate
-        signing_key = serialization.load_der_private_key(key_der, password=None)
+        signing_key = serialization.load_der_private_key(key_der, password=None, backend=default_backend())
         builder = CertificateBuilder()
         builder = builder.subject_name(x509.Name([
             x509.NameAttribute(NameOID.COMMON_NAME, subject_name),

sdk/attestation/azure-security-attestation/tests/test_policy_getset.py

@@ -24,6 +24,7 @@
 import functools
 import cryptography
 import cryptography.x509
+from cryptography.hazmat.backends import default_backend
 from cryptography.hazmat.primitives import serialization
 import base64
 import pytest
@@ -83,7 +84,7 @@ def test_aad_set_policy_sgx_unsecured(self, attestation_aad_url):
         assert policy_get_response.value == attestation_policy
 
         expected_policy = AttestationToken(body=StoredAttestationPolicy(attestation_policy=str(attestation_policy).encode('utf-8')))
-        hasher = hashes.Hash(hashes.SHA256())
+        hasher = hashes.Hash(hashes.SHA256(), backend=default_backend())
         hasher.update(expected_policy.serialize().encode('utf-8'))
         expected_hash = hasher.finalize()
 
@@ -106,7 +107,7 @@ def test_aad_set_policy_sgx_secured(self, attestation_aad_url, attestation_polic
         assert policy_get_response.value == attestation_policy
 
         expected_policy = AttestationToken(body=StoredAttestationPolicy(attestation_policy=str(attestation_policy).encode('ascii')), signer=AttestationSigningKey(key, signing_certificate))
-        hasher = hashes.Hash(hashes.SHA256())
+        hasher = hashes.Hash(hashes.SHA256(), backend=default_backend())
         hasher.update(expected_policy.serialize().encode('utf-8'))
         expected_hash = hasher.finalize()
 
@@ -129,7 +130,7 @@ def test_isolated_set_policy_sgx_secured(self, attestation_isolated_url, attesta
         assert policy_get_response.value == attestation_policy
 
         expected_policy = AttestationToken(body=StoredAttestationPolicy(attestation_policy=str(attestation_policy).encode('ascii')), signer=AttestationSigningKey(key, decoded_cert))
-        hasher = hashes.Hash(hashes.SHA256())
+        hasher = hashes.Hash(hashes.SHA256(), backend=default_backend())
         hasher.update(expected_policy.serialize().encode('utf-8'))
         expected_hash = hasher.finalize()