support RC2-CBC (#10407)

This PR supports a bad old algorithm to support a scapy use case, but
does not expose support for effective key bits or any key length other
than 128-bit. CBC support only -- no other modes.

2 files changed, 42 insertions, 2 deletions

diff --git a/tests/hazmat/primitives/decrepit/test_rc2.py b/tests/hazmat/primitives/decrepit/test_rc2.py
new file mode 100644
index 0000000..ecd4ce2
--- /dev/null
+++ b/tests/hazmat/primitives/decrepit/test_rc2.py
@@ -0,0 +1,37 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+"""
+Test using the NIST Test Vectors
+"""
+
+
+import binascii
+import os
+
+import pytest
+
+from cryptography.hazmat.decrepit.ciphers.algorithms import RC2
+from cryptography.hazmat.primitives.ciphers import modes
+
+from ....utils import load_nist_vectors
+from ..utils import generate_encrypt_test
+
+
+@pytest.mark.supported(
+    only_if=lambda backend: backend.cipher_supported(
+        RC2(b"\x00" * 16), modes.CBC(b"\x00" * 8)
+    ),
+    skip_message="Does not support RC2 CBC",
+)
+class TestRC2ModeCBC:
+    test_kat = generate_encrypt_test(
+        load_nist_vectors,
+        os.path.join("ciphers", "RC2"),
+        [
+            "rc2-cbc.txt",
+        ],
+        lambda key, **kwargs: RC2(binascii.unhexlify(key)),
+        lambda iv, **kwargs: modes.CBC(binascii.unhexlify(iv)),
+    )
diff --git a/tests/hazmat/primitives/test_pkcs12.py b/tests/hazmat/primitives/test_pkcs12.py
index cd9c279..f49c98a 100644
--- a/tests/hazmat/primitives/test_pkcs12.py
+++ b/tests/hazmat/primitives/test_pkcs12.py
@@ -10,7 +10,7 @@ import pytest
 
 from cryptography import x509
 from cryptography.exceptions import UnsupportedAlgorithm
-from cryptography.hazmat.backends.openssl.backend import _RC2
+from cryptography.hazmat.decrepit.ciphers.algorithms import RC2
 from cryptography.hazmat.primitives import hashes, serialization
 from cryptography.hazmat.primitives.asymmetric import (
     dsa,
@@ -19,6 +19,7 @@ from cryptography.hazmat.primitives.asymmetric import (
     ed25519,
     rsa,
 )
+from cryptography.hazmat.primitives.ciphers.modes import CBC
 from cryptography.hazmat.primitives.serialization import (
     Encoding,
     PublicFormat,
@@ -81,7 +82,9 @@ class TestPKCS12Loading:
         ],
     )
     @pytest.mark.supported(
-        only_if=lambda backend: backend.cipher_supported(_RC2(), None),
+        only_if=lambda backend: backend.cipher_supported(
+            RC2(b"0" * 16), CBC(b"0" * 8)
+        ),
         skip_message="Does not support RC2",
     )
     def test_load_pkcs12_ec_keys_rc2(self, filename, password, backend):