| # 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. |
| |
| """Pre-generated KeyTemplate for Aead. |
| |
| One can use these templates to generate a new tink_pb2.Keyset with |
| tink_pb2.KeysetHandle. To generate a new keyset that contains a single |
| aes_eax_pb2.AesEaxKey, one can do: |
| handle = keyset_handle.KeysetHandle(aead_key_templates.AES128_EAX). |
| """ |
| |
| from __future__ import absolute_import |
| from __future__ import division |
| # Placeholder for import for type annotations |
| from __future__ import print_function |
| |
| from tink.proto import aes_cmac_prf_pb2 |
| from tink.proto import common_pb2 |
| from tink.proto import hkdf_prf_pb2 |
| from tink.proto import hmac_prf_pb2 |
| from tink.proto import tink_pb2 |
| |
| _AES_CMAC_PRF_KEY_TYPE_URL = ( |
| 'type.googleapis.com/google.crypto.tink.AesCmacPrfKey') |
| _HMAC_PRF_KEY_TYPE_URL = 'type.googleapis.com/google.crypto.tink.HmacPrfKey' |
| _HKDF_PRF_KEY_TYPE_URL = 'type.googleapis.com/google.crypto.tink.HkdfPrfKey' |
| |
| |
| def _create_aes_cmac_key_template(key_size: int) -> tink_pb2.KeyTemplate: |
| """Creates an AES CMAC PRF KeyTemplate, and fills in its values.""" |
| key_format = aes_cmac_prf_pb2.AesCmacPrfKeyFormat() |
| key_format.key_size = key_size |
| key_format.version = 0 |
| key_template = tink_pb2.KeyTemplate() |
| key_template.value = key_format.SerializeToString() |
| key_template.type_url = _AES_CMAC_PRF_KEY_TYPE_URL |
| key_template.output_prefix_type = tink_pb2.RAW |
| return key_template |
| |
| |
| def _create_hmac_key_template( |
| key_size: int, hash_type: common_pb2.HashType) -> tink_pb2.KeyTemplate: |
| """Creates an HMAC PRF KeyTemplate, and fills in its values.""" |
| key_format = hmac_prf_pb2.HmacPrfKeyFormat() |
| key_format.params.hash = hash_type |
| key_format.key_size = key_size |
| key_format.version = 0 |
| key_template = tink_pb2.KeyTemplate() |
| key_template.value = key_format.SerializeToString() |
| key_template.type_url = _HMAC_PRF_KEY_TYPE_URL |
| key_template.output_prefix_type = tink_pb2.RAW |
| return key_template |
| |
| |
| def _create_hkdf_key_template( |
| key_size: int, hash_type: common_pb2.HashType) -> tink_pb2.KeyTemplate: |
| """Creates an HKDF PRF KeyTemplate, and fills in its values.""" |
| key_format = hkdf_prf_pb2.HkdfPrfKeyFormat() |
| key_format.params.hash = hash_type |
| key_format.key_size = key_size |
| key_format.version = 0 |
| key_template = tink_pb2.KeyTemplate() |
| key_template.value = key_format.SerializeToString() |
| key_template.type_url = _HKDF_PRF_KEY_TYPE_URL |
| key_template.output_prefix_type = tink_pb2.RAW |
| return key_template |
| |
| |
| AES_CMAC = _create_aes_cmac_key_template(key_size=32) |
| HMAC_SHA256 = _create_hmac_key_template( |
| key_size=32, hash_type=common_pb2.SHA256) |
| HMAC_SHA512 = _create_hmac_key_template( |
| key_size=64, hash_type=common_pb2.SHA512) |
| HKDF_SHA256 = _create_hkdf_key_template( |
| key_size=32, hash_type=common_pb2.SHA256) |
