diff options
| -rw-r--r-- | docs/hazmat/primitives/aead.rst | 2 | ||||
| -rw-r--r-- | src/cryptography/hazmat/primitives/ciphers/aead.py | 2 | ||||
| -rw-r--r-- | tests/wycheproof/test_aes.py | 40 |
3 files changed, 41 insertions, 3 deletions
diff --git a/docs/hazmat/primitives/aead.rst b/docs/hazmat/primitives/aead.rst index a54cc6fa..06fecc5a 100644 --- a/docs/hazmat/primitives/aead.rst +++ b/docs/hazmat/primitives/aead.rst @@ -169,7 +169,7 @@ also support providing integrity for associated data which is not encrypted. :param int tag_length: The length of the authentication tag. This defaults to 16 bytes and it is **strongly** recommended that you do not make it shorter unless absolutely necessary. Valid tag - lengths are 4, 6, 8, 12, 14, and 16. + lengths are 4, 6, 8, 10, 12, 14, and 16. :raises cryptography.exceptions.UnsupportedAlgorithm: If the version of OpenSSL does not support AES-CCM. diff --git a/src/cryptography/hazmat/primitives/ciphers/aead.py b/src/cryptography/hazmat/primitives/ciphers/aead.py index e5197653..16899d00 100644 --- a/src/cryptography/hazmat/primitives/ciphers/aead.py +++ b/src/cryptography/hazmat/primitives/ciphers/aead.py @@ -75,7 +75,7 @@ class AESCCM(object): if not isinstance(tag_length, int): raise TypeError("tag_length must be an integer") - if tag_length not in (4, 6, 8, 12, 14, 16): + if tag_length not in (4, 6, 8, 10, 12, 14, 16): raise ValueError("Invalid tag_length") self._tag_length = tag_length diff --git a/tests/wycheproof/test_aes.py b/tests/wycheproof/test_aes.py index a3d75123..55e45454 100644 --- a/tests/wycheproof/test_aes.py +++ b/tests/wycheproof/test_aes.py @@ -14,7 +14,9 @@ from cryptography.hazmat.primitives import padding from cryptography.hazmat.primitives.ciphers import ( Cipher, algorithms, modes ) -from cryptography.hazmat.primitives.ciphers.aead import AESGCM +from cryptography.hazmat.primitives.ciphers.aead import AESCCM, AESGCM + +from ..hazmat.primitives.test_aead import _aead_supported @pytest.mark.requires_backend_interface(interface=CipherBackend) @@ -104,3 +106,39 @@ def test_aes_gcm_aead_api(backend, wycheproof): else: with pytest.raises(InvalidTag): aesgcm.decrypt(iv, ct + tag, aad) + + +@pytest.mark.skipif( + not _aead_supported(AESCCM), + reason="Requires OpenSSL with AES-CCM support", +) +@pytest.mark.requires_backend_interface(interface=CipherBackend) +@pytest.mark.wycheproof_tests("aes_ccm_test.json") +def test_aes_ccm_aead_api(backend, wycheproof): + key = binascii.unhexlify(wycheproof.testcase["key"]) + iv = binascii.unhexlify(wycheproof.testcase["iv"]) + aad = binascii.unhexlify(wycheproof.testcase["aad"]) + msg = binascii.unhexlify(wycheproof.testcase["msg"]) + ct = binascii.unhexlify(wycheproof.testcase["ct"]) + tag = binascii.unhexlify(wycheproof.testcase["tag"]) + + if ( + wycheproof.invalid and + wycheproof.testcase["comment"] == "Invalid tag size" + ): + with pytest.raises(ValueError): + AESCCM(key, tag_length=wycheproof.testgroup["tagSize"] // 8) + return + + aesccm = AESCCM(key, tag_length=wycheproof.testgroup["tagSize"] // 8) + if wycheproof.valid or wycheproof.acceptable: + computed_ct = aesccm.encrypt(iv, msg, aad) + assert computed_ct == ct + tag + computed_msg = aesccm.decrypt(iv, ct + tag, aad) + assert computed_msg == msg + elif not 7 <= len(iv) <= 13: + with pytest.raises(ValueError): + aesccm.decrypt(iv, ct + tag, aad) + else: + with pytest.raises(InvalidTag): + aesccm.decrypt(iv, ct + tag, aad) |