| # Copyright 2020 Google LLC |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| """Cross-language tests for Hybrid Encryption.""" |
| |
| # Placeholder for import for type annotations |
| from typing import Iterable, Text, Tuple |
| |
| from absl.testing import absltest |
| from absl.testing import parameterized |
| |
| import tink |
| from tink import hybrid |
| |
| from tink.proto import tink_pb2 |
| from tink.testing import keyset_builder |
| from util import supported_key_types |
| from util import testing_servers |
| |
| SUPPORTED_LANGUAGES = testing_servers.SUPPORTED_LANGUAGES_BY_PRIMITIVE['hybrid'] |
| |
| |
| def setUpModule(): |
| hybrid.register() |
| testing_servers.start('hybrid') |
| |
| |
| def tearDownModule(): |
| testing_servers.stop() |
| |
| |
| def all_hybrid_private_key_template_names() -> Iterable[Text]: |
| """Yields all Hybrid Encryption private key template names.""" |
| for key_type in supported_key_types.HYBRID_PRIVATE_KEY_TYPES: |
| for key_template_name in supported_key_types.KEY_TEMPLATE_NAMES[key_type]: |
| yield key_template_name |
| |
| |
| class HybridEncryptionTest(parameterized.TestCase): |
| |
| @parameterized.parameters(all_hybrid_private_key_template_names()) |
| def test_encrypt_decrypt(self, key_template_name): |
| supported_langs = supported_key_types.SUPPORTED_LANGUAGES_BY_TEMPLATE_NAME[ |
| key_template_name] |
| self.assertNotEmpty(supported_langs) |
| key_template = supported_key_types.KEY_TEMPLATE[key_template_name] |
| # Take the first supported language to generate the private keyset. |
| private_keyset = testing_servers.new_keyset(supported_langs[0], |
| key_template) |
| supported_decs = [ |
| testing_servers.hybrid_decrypt(lang, private_keyset) |
| for lang in supported_langs |
| ] |
| unsupported_decs = [ |
| testing_servers.hybrid_decrypt(lang, private_keyset) |
| for lang in SUPPORTED_LANGUAGES |
| if lang not in supported_langs |
| ] |
| public_keyset = testing_servers.public_keyset(supported_langs[0], |
| private_keyset) |
| supported_encs = [ |
| testing_servers.hybrid_encrypt(lang, public_keyset) |
| for lang in supported_langs |
| ] |
| unsupported_encs = [ |
| testing_servers.hybrid_encrypt(lang, public_keyset) |
| for lang in testing_servers.LANGUAGES |
| if lang not in supported_langs |
| ] |
| for enc in supported_encs: |
| plaintext = ( |
| b'This is some plaintext message to be encrypted using key_template ' |
| b'%s in %s.' % (key_template_name.encode('utf8'), |
| enc.lang.encode('utf8'))) |
| context_info = ( |
| b'Some context info for %s using %s for encryption.' % |
| (key_template_name.encode('utf8'), enc.lang.encode('utf8'))) |
| ciphertext = enc.encrypt(plaintext, context_info) |
| for dec in supported_decs: |
| output = dec.decrypt(ciphertext, context_info) |
| self.assertEqual(output, plaintext) |
| for dec in unsupported_decs: |
| with self.assertRaises( |
| tink.TinkError, |
| msg='Language %s supports hybrid decrypt with %s unexpectedly' % |
| (dec.lang, key_template_name)): |
| dec.decrypt(ciphertext, context_info) |
| for enc in unsupported_encs: |
| with self.assertRaises( |
| tink.TinkError, |
| msg='Language %s supports hybrid encrypt with %s unexpectedly' % ( |
| enc.lang, key_template_name)): |
| enc.encrypt(b'plaintext', b'context_info') |
| |
| |
| # If the implementations work fine for keysets with single keys, then key |
| # rotation should work if the primitive wrapper is implemented correctly. |
| # These wrappers do not depend on the key type, so it should be fine to always |
| # test with the same key type. But since the wrapper needs to treat keys |
| # with output prefix RAW differently, we also include such a template for that. |
| KEY_ROTATION_TEMPLATES = [ |
| hybrid.hybrid_key_templates.ECIES_P256_HKDF_HMAC_SHA256_AES128_GCM, |
| keyset_builder.raw_template( |
| hybrid.hybrid_key_templates.ECIES_P256_HKDF_HMAC_SHA256_AES128_GCM) |
| ] |
| |
| |
| def key_rotation_test_cases( |
| ) -> Iterable[Tuple[Text, Text, tink_pb2.KeyTemplate, tink_pb2.KeyTemplate]]: |
| for enc_lang in SUPPORTED_LANGUAGES: |
| for dec_lang in SUPPORTED_LANGUAGES: |
| for old_key_tmpl in KEY_ROTATION_TEMPLATES: |
| for new_key_tmpl in KEY_ROTATION_TEMPLATES: |
| yield (enc_lang, dec_lang, old_key_tmpl, new_key_tmpl) |
| |
| |
| class HybridEncryptionKeyRotationTest(parameterized.TestCase): |
| |
| @parameterized.parameters(key_rotation_test_cases()) |
| def test_key_rotation(self, enc_lang, dec_lang, old_key_tmpl, new_key_tmpl): |
| # Do a key rotation from an old key generated from old_key_tmpl to a new |
| # key generated from new_key_tmpl. Encryption and decryption are done |
| # in languages enc_lang and dec_lang. |
| builder = keyset_builder.new_keyset_builder() |
| older_key_id = builder.add_new_key(old_key_tmpl) |
| builder.set_primary_key(older_key_id) |
| dec1 = testing_servers.hybrid_decrypt(enc_lang, builder.keyset()) |
| enc1 = testing_servers.hybrid_encrypt(dec_lang, builder.public_keyset()) |
| newer_key_id = builder.add_new_key(new_key_tmpl) |
| dec2 = testing_servers.hybrid_decrypt(enc_lang, builder.keyset()) |
| enc2 = testing_servers.hybrid_encrypt(dec_lang, builder.public_keyset()) |
| |
| builder.set_primary_key(newer_key_id) |
| dec3 = testing_servers.hybrid_decrypt(enc_lang, builder.keyset()) |
| enc3 = testing_servers.hybrid_encrypt(dec_lang, builder.public_keyset()) |
| |
| builder.disable_key(older_key_id) |
| dec4 = testing_servers.hybrid_decrypt(enc_lang, builder.keyset()) |
| enc4 = testing_servers.hybrid_encrypt(dec_lang, builder.public_keyset()) |
| self.assertNotEqual(older_key_id, newer_key_id) |
| |
| # p1 encrypts with the older key. So p1, p2 and p3 can decrypt it, |
| # but not p4. |
| ciphertext1 = enc1.encrypt(b'plaintext', b'context') |
| self.assertEqual(dec1.decrypt(ciphertext1, b'context'), b'plaintext') |
| self.assertEqual(dec2.decrypt(ciphertext1, b'context'), b'plaintext') |
| self.assertEqual(dec3.decrypt(ciphertext1, b'context'), b'plaintext') |
| with self.assertRaises(tink.TinkError): |
| _ = dec4.decrypt(ciphertext1, b'context') |
| |
| # p2 encrypts with the older key. So p1, p2 and p3 can decrypt it, |
| # but not p4. |
| ciphertext2 = enc2.encrypt(b'plaintext', b'context') |
| self.assertEqual(dec1.decrypt(ciphertext2, b'context'), b'plaintext') |
| self.assertEqual(dec2.decrypt(ciphertext2, b'context'), b'plaintext') |
| self.assertEqual(dec3.decrypt(ciphertext2, b'context'), b'plaintext') |
| with self.assertRaises(tink.TinkError): |
| _ = dec4.decrypt(ciphertext2, b'context') |
| |
| # p3 encrypts with the newer key. So p2, p3 and p4 can decrypt it, |
| # but not p1. |
| ciphertext3 = enc3.encrypt(b'plaintext', b'context') |
| with self.assertRaises(tink.TinkError): |
| _ = dec1.decrypt(ciphertext3, b'context') |
| self.assertEqual(dec2.decrypt(ciphertext3, b'context'), b'plaintext') |
| self.assertEqual(dec3.decrypt(ciphertext3, b'context'), b'plaintext') |
| self.assertEqual(dec4.decrypt(ciphertext3, b'context'), b'plaintext') |
| |
| # p4 encrypts with the newer key. So p2, p3 and p4 can decrypt it, |
| # but not p1. |
| ciphertext4 = enc4.encrypt(b'plaintext', b'context') |
| with self.assertRaises(tink.TinkError): |
| _ = dec1.decrypt(ciphertext4, b'context') |
| self.assertEqual(dec2.decrypt(ciphertext4, b'context'), b'plaintext') |
| self.assertEqual(dec3.decrypt(ciphertext4, b'context'), b'plaintext') |
| self.assertEqual(dec4.decrypt(ciphertext4, b'context'), b'plaintext') |
| |
| |
| if __name__ == '__main__': |
| absltest.main() |