1 /* 2 * Copyright 2015 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_KEY_EXCHANGE_H_ 18 #define SYSTEM_KEYMASTER_KEY_EXCHANGE_H_ 19 20 #include <openssl/ec.h> 21 22 #include <keymaster/serializable.h> 23 24 namespace keymaster { 25 26 /** 27 * KeyExchange is an abstract class that provides an interface to a 28 * key-exchange primitive. 29 */ 30 class KeyExchange { 31 public: ~KeyExchange()32 virtual ~KeyExchange() {} 33 34 /** 35 * CalculateSharedKey computes the shared key between the local private key 36 * (which is implicitly known by a KeyExchange object) and a public value 37 * from the peer. 38 */ 39 virtual bool CalculateSharedKey(const Buffer& peer_public_value, Buffer* shared_key) const = 0; 40 virtual bool CalculateSharedKey(const uint8_t* peer_public_value, size_t peer_public_value_len, 41 Buffer* shared_key) const = 0; 42 43 /** 44 * public_value writes to |public_value| the local public key which can be 45 * sent to a peer in order to complete a key exchange. 46 */ 47 virtual bool public_value(Buffer* public_value) const = 0; 48 }; 49 50 } // namespace keymaster 51 52 #endif // SYSTEM_KEYMASTER_KEY_EXCHANGE_H_ 53