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 #ifndef SYSTEM_KEYMASTER_AES_KEY_H_ 18 #define SYSTEM_KEYMASTER_AES_KEY_H_ 19 20 #include <openssl/aes.h> 21 22 #include "symmetric_key.h" 23 24 namespace keymaster { 25 26 const size_t kMinGcmTagLength = 12 * 8; 27 const size_t kMaxGcmTagLength = 16 * 8; 28 29 class AesKeyFactory : public SymmetricKeyFactory { 30 public: AesKeyFactory(const SoftwareKeyBlobMaker * blob_maker,const RandomSource * random_source)31 explicit AesKeyFactory(const SoftwareKeyBlobMaker* blob_maker, 32 const RandomSource* random_source) : 33 SymmetricKeyFactory(blob_maker, random_source) {} 34 registry_key()35 keymaster_algorithm_t registry_key() const { return KM_ALGORITHM_AES; } 36 37 keymaster_error_t LoadKey(KeymasterKeyBlob&& key_material, 38 const AuthorizationSet& additional_params, 39 AuthorizationSet&& hw_enforced, 40 AuthorizationSet&& sw_enforced, 41 UniquePtr<Key>* key) const override; 42 43 OperationFactory* GetOperationFactory(keymaster_purpose_t purpose) const override; 44 45 private: key_size_supported(size_t key_size_bits)46 bool key_size_supported(size_t key_size_bits) const override { 47 return key_size_bits == 128 || key_size_bits == 192 || key_size_bits == 256; 48 } 49 keymaster_error_t validate_algorithm_specific_new_key_params( 50 const AuthorizationSet& key_description) const override; 51 }; 52 53 class AesKey : public SymmetricKey { 54 public: AesKey(KeymasterKeyBlob && key_material,AuthorizationSet && hw_enforced,AuthorizationSet && sw_enforced,const KeyFactory * key_factory)55 AesKey(KeymasterKeyBlob&& key_material, AuthorizationSet&& hw_enforced, 56 AuthorizationSet&& sw_enforced, 57 const KeyFactory* key_factory) 58 : SymmetricKey(move(key_material), move(hw_enforced), move(sw_enforced), key_factory) {} 59 }; 60 61 } // namespace keymaster 62 63 #endif // SYSTEM_KEYMASTER_AES_KEY_H_ 64