add wycheproof gcm tests (#4349)
* add wycheproof gcm tests
* add AEAD test
diff --git a/tests/wycheproof/test_aes.py b/tests/wycheproof/test_aes.py
index 65db9cd..929ad8d 100644
--- a/tests/wycheproof/test_aes.py
+++ b/tests/wycheproof/test_aes.py
@@ -13,6 +13,7 @@
from cryptography.hazmat.primitives.ciphers import (
Cipher, algorithms, modes
)
+from cryptography.hazmat.primitives.ciphers.aead import AESGCM
@pytest.mark.requires_backend_interface(interface=CipherBackend)
@@ -40,3 +41,56 @@
assert computed_ct != ct
with pytest.raises(ValueError):
unpadder.update(padded_msg) + unpadder.finalize()
+
+
+@pytest.mark.requires_backend_interface(interface=CipherBackend)
+@pytest.mark.wycheproof_tests("aes_gcm_test.json")
+def test_aes_gcm(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.valid or wycheproof.acceptable:
+ enc = Cipher(algorithms.AES(key), modes.GCM(iv), backend).encryptor()
+ enc.authenticate_additional_data(aad)
+ computed_ct = enc.update(msg) + enc.finalize()
+ computed_tag = enc.tag
+ assert computed_ct == ct
+ assert computed_tag == tag
+ dec = Cipher(
+ algorithms.AES(key),
+ modes.GCM(iv, tag, min_tag_length=len(tag)),
+ backend
+ ).decryptor()
+ dec.authenticate_additional_data(aad)
+ computed_msg = dec.update(ct) + dec.finalize()
+ assert computed_msg == msg
+ else:
+ # All invalid GCM tests are IV len 0 right now
+ assert len(iv) == 0
+ with pytest.raises(ValueError):
+ Cipher(algorithms.AES(key), modes.GCM(iv), backend)
+
+
+@pytest.mark.requires_backend_interface(interface=CipherBackend)
+@pytest.mark.wycheproof_tests("aes_gcm_test.json")
+def test_aes_gcm_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"])
+ aesgcm = AESGCM(key)
+ if wycheproof.valid or wycheproof.acceptable:
+ computed_ct = aesgcm.encrypt(iv, msg, aad)
+ assert computed_ct == ct + tag
+ computed_msg = aesgcm.decrypt(iv, ct + tag, aad)
+ assert computed_msg == msg
+ else:
+ # All invalid GCM tests are IV len 0 right now
+ assert len(iv) == 0
+ with pytest.raises(ValueError):
+ aesgcm.encrypt(iv, msg, aad)