1 /* 2 * Copyright 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #pragma once 18 19 #include <openssl/aes.h> 20 21 #include "symmetric_key.h" 22 23 namespace keymaster { 24 25 const size_t kMinGcmTagLength = 12 * 8; 26 const size_t kMaxGcmTagLength = 16 * 8; 27 28 class AesKeyFactory : public SymmetricKeyFactory { 29 public: AesKeyFactory(const SoftwareKeyBlobMaker & blob_maker,const RandomSource & random_source)30 explicit AesKeyFactory(const SoftwareKeyBlobMaker& blob_maker, 31 const RandomSource& random_source) 32 : SymmetricKeyFactory(blob_maker, random_source) {} 33 registry_key()34 keymaster_algorithm_t registry_key() const { return KM_ALGORITHM_AES; } 35 36 keymaster_error_t LoadKey(KeymasterKeyBlob&& key_material, 37 const AuthorizationSet& additional_params, 38 AuthorizationSet&& hw_enforced, AuthorizationSet&& sw_enforced, 39 UniquePtr<Key>* key) const override; 40 41 OperationFactory* GetOperationFactory(keymaster_purpose_t purpose) const override; 42 43 private: key_size_supported(size_t key_size_bits)44 bool key_size_supported(size_t key_size_bits) const override { 45 return key_size_bits == 128 || key_size_bits == 192 || key_size_bits == 256; 46 } 47 keymaster_error_t validate_algorithm_specific_new_key_params( 48 const AuthorizationSet& key_description) const override; 49 }; 50 51 class AesKey : public SymmetricKey { 52 public: AesKey(KeymasterKeyBlob && key_material,AuthorizationSet && hw_enforced,AuthorizationSet && sw_enforced,const KeyFactory * key_factory)53 AesKey(KeymasterKeyBlob&& key_material, AuthorizationSet&& hw_enforced, 54 AuthorizationSet&& sw_enforced, const KeyFactory* key_factory) 55 : SymmetricKey(move(key_material), move(hw_enforced), move(sw_enforced), key_factory) {} 56 }; 57 58 } // namespace keymaster 59