| # 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 the StreamingAead primitive.""" |
| |
| import io |
| from typing import Iterable |
| |
| from absl.testing import absltest |
| from absl.testing import parameterized |
| |
| import tink |
| from tink import streaming_aead |
| |
| 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['streaming_aead']) |
| |
| # About 49KB. |
| LONG_PLAINTEXT = b' '.join(b'%d' % i for i in range(10000)) |
| |
| |
| def key_rotation_test_cases(): |
| for enc_lang in SUPPORTED_LANGUAGES: |
| for dec_lang in SUPPORTED_LANGUAGES: |
| yield (enc_lang, dec_lang) |
| |
| |
| def setUpModule(): |
| streaming_aead.register() |
| testing_servers.start('streaming_aead') |
| |
| |
| def tearDownModule(): |
| testing_servers.stop() |
| |
| |
| def all_streaming_aead_key_template_names() -> Iterable[str]: |
| """Yields all Streaming AEAD key template names.""" |
| for key_type in supported_key_types.STREAMING_AEAD_KEY_TYPES: |
| for key_template_name in supported_key_types.KEY_TEMPLATE_NAMES[key_type]: |
| yield key_template_name |
| |
| |
| class StreamingAeadPythonTest(parameterized.TestCase): |
| |
| @parameterized.parameters(all_streaming_aead_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 keyset. |
| keyset = testing_servers.new_keyset(supported_langs[0], key_template) |
| supported_streaming_aeads = [ |
| testing_servers.streaming_aead(lang, keyset) for lang in supported_langs |
| ] |
| unsupported_streaming_aeads = [ |
| testing_servers.streaming_aead(lang, keyset) |
| for lang in SUPPORTED_LANGUAGES |
| if lang not in supported_langs |
| ] |
| for p in supported_streaming_aeads: |
| desc = ( |
| b'This is some plaintext message to be encrypted using key_template ' |
| b'%s using %s for encryption.' |
| % (key_template_name.encode('utf8'), p.lang.encode('utf8'))) |
| plaintext = desc + LONG_PLAINTEXT |
| associated_data = ( |
| b'Some associated data for %s using %s for encryption.' % |
| (key_template_name.encode('utf8'), p.lang.encode('utf8'))) |
| plaintext_stream = io.BytesIO(plaintext) |
| ciphertext_result_stream = p.new_encrypting_stream( |
| plaintext_stream, associated_data) |
| ciphertext = ciphertext_result_stream.read() |
| for p2 in supported_streaming_aeads: |
| ciphertext_stream = io.BytesIO(ciphertext) |
| decrypted_stream = p2.new_decrypting_stream( |
| ciphertext_stream, associated_data) |
| self.assertEqual(decrypted_stream.read(), plaintext) |
| for p2 in unsupported_streaming_aeads: |
| with self.assertRaises( |
| tink.TinkError, |
| msg='Language %s supports streaming AEAD decryption with %s ' |
| 'unexpectedly' % (p2.lang, key_template_name)): |
| ciphertext_stream = io.BytesIO(ciphertext) |
| decrypted_stream = p2.new_decrypting_stream( |
| ciphertext_stream, associated_data) |
| for p in unsupported_streaming_aeads: |
| with self.assertRaises( |
| tink.TinkError, |
| msg='Language %s supports streaming AEAD encryption with %s ' |
| 'unexpectedly' % (p.lang, key_template_name)): |
| plaintext_stream = io.BytesIO(b'plaintext') |
| ciphertext_result_stream = p.new_encrypting_stream( |
| plaintext_stream, b'associated_data') |
| |
| @parameterized.parameters(key_rotation_test_cases()) |
| def test_key_rotation(self, enc_lang, dec_lang): |
| # Do a key rotation from an old key to a new key. |
| # 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( |
| streaming_aead.streaming_aead_key_templates.AES128_GCM_HKDF_4KB) |
| builder.set_primary_key(older_key_id) |
| enc1 = testing_servers.streaming_aead(enc_lang, builder.keyset()) |
| dec1 = testing_servers.streaming_aead(dec_lang, builder.keyset()) |
| newer_key_id = builder.add_new_key( |
| streaming_aead.streaming_aead_key_templates.AES256_GCM_HKDF_4KB) |
| enc2 = testing_servers.streaming_aead(enc_lang, builder.keyset()) |
| dec2 = testing_servers.streaming_aead(dec_lang, builder.keyset()) |
| |
| builder.set_primary_key(newer_key_id) |
| enc3 = testing_servers.streaming_aead(enc_lang, builder.keyset()) |
| dec3 = testing_servers.streaming_aead(dec_lang, builder.keyset()) |
| |
| builder.disable_key(older_key_id) |
| enc4 = testing_servers.streaming_aead(enc_lang, builder.keyset()) |
| dec4 = testing_servers.streaming_aead(dec_lang, builder.keyset()) |
| |
| self.assertNotEqual(older_key_id, newer_key_id) |
| # 1 encrypts with the older key. So 1, 2 and 3 can decrypt it, but not 4. |
| plaintext = LONG_PLAINTEXT |
| ad = b'associated_data' |
| ciphertext1 = enc1.new_encrypting_stream(io.BytesIO(plaintext), ad).read() |
| self.assertEqual( |
| dec1.new_decrypting_stream(io.BytesIO(ciphertext1), ad).read(), |
| plaintext) |
| self.assertEqual( |
| dec2.new_decrypting_stream(io.BytesIO(ciphertext1), ad).read(), |
| plaintext) |
| self.assertEqual( |
| dec3.new_decrypting_stream(io.BytesIO(ciphertext1), ad).read(), |
| plaintext) |
| with self.assertRaises(tink.TinkError): |
| _ = dec4.new_decrypting_stream(io.BytesIO(ciphertext1), ad).read() |
| |
| # 2 encrypts with the older key. So 1, 2 and 3 can decrypt it, but not 4. |
| ciphertext2 = enc2.new_encrypting_stream(io.BytesIO(plaintext), ad).read() |
| self.assertEqual( |
| dec1.new_decrypting_stream(io.BytesIO(ciphertext2), ad).read(), |
| plaintext) |
| self.assertEqual( |
| dec2.new_decrypting_stream(io.BytesIO(ciphertext2), ad).read(), |
| plaintext) |
| self.assertEqual( |
| dec3.new_decrypting_stream(io.BytesIO(ciphertext2), ad).read(), |
| plaintext) |
| with self.assertRaises(tink.TinkError): |
| _ = dec4.new_decrypting_stream(io.BytesIO(ciphertext2), ad).read() |
| |
| # 3 encrypts with the newer key. So 2, 3 and 4 can decrypt it, but not 1. |
| ciphertext3 = enc3.new_encrypting_stream(io.BytesIO(plaintext), ad).read() |
| with self.assertRaises(tink.TinkError): |
| _ = dec1.new_decrypting_stream(io.BytesIO(ciphertext3), ad).read() |
| self.assertEqual( |
| dec2.new_decrypting_stream(io.BytesIO(ciphertext3), ad).read(), |
| plaintext) |
| self.assertEqual( |
| dec3.new_decrypting_stream(io.BytesIO(ciphertext3), ad).read(), |
| plaintext) |
| self.assertEqual( |
| dec4.new_decrypting_stream(io.BytesIO(ciphertext3), ad).read(), |
| plaintext) |
| |
| # 4 encrypts with the newer key. So 2, 3 and 4 can decrypt it, but not 1. |
| ciphertext4 = enc4.new_encrypting_stream(io.BytesIO(plaintext), ad).read() |
| with self.assertRaises(tink.TinkError): |
| _ = dec1.new_decrypting_stream(io.BytesIO(ciphertext4), ad).read() |
| self.assertEqual( |
| dec2.new_decrypting_stream(io.BytesIO(ciphertext4), ad).read(), |
| plaintext) |
| self.assertEqual( |
| dec3.new_decrypting_stream(io.BytesIO(ciphertext4), ad).read(), |
| plaintext) |
| self.assertEqual( |
| dec4.new_decrypting_stream(io.BytesIO(ciphertext4), ad).read(), |
| plaintext) |
| |
| if __name__ == '__main__': |
| absltest.main() |
