1 /* 2 * Copyright 2019 Google LLC 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 FCP_SECAGG_SERVER_SECAGG_SERVER_R0_ADVERTISE_KEYS_STATE_H_ 18 #define FCP_SECAGG_SERVER_SECAGG_SERVER_R0_ADVERTISE_KEYS_STATE_H_ 19 20 #include <memory> 21 22 #include "fcp/secagg/server/secagg_server_state.h" 23 24 namespace fcp { 25 namespace secagg { 26 27 // This class is the State for the SecAggServer when it is in the 28 // Round 0: Advertise state. The server begins in this state. This state 29 // collects public ECDH keys from clients, stores the one of them that will be 30 // used later in running the PRNG, and then sends to each client both public 31 // keys from each of its neighbors. It also computes and stores the session ID 32 // from the received keys, and sends the session ID to each client along with 33 // its neighbor's keys. This state should transition to Round 1: Share Keys, but 34 // might transition to Aborted if too many clients abort. 35 36 class SecAggServerR0AdvertiseKeysState : public SecAggServerState { 37 public: 38 explicit SecAggServerR0AdvertiseKeysState( 39 std::unique_ptr<SecAggServerProtocolImpl> impl); 40 41 ~SecAggServerR0AdvertiseKeysState() override; 42 43 // Handles an advertise keys response or abort message from a client. 44 Status HandleMessage(uint32_t client_id, 45 const ClientToServerWrapperMessage& message) override; 46 47 bool IsNumberOfIncludedInputsCommitted() const override; 48 49 int MinimumMessagesNeededForNextRound() const override; 50 51 int NumberOfPendingClients() const override; 52 53 StatusOr<std::unique_ptr<SecAggServerState> > ProceedToNextRound() override; 54 55 // This will return true only after minimum_number_of_clients_to_proceed 56 // clients have sent messages (and not subsequently aborted). 57 bool ReadyForNextRound() const override; 58 59 private: 60 void HandleAbortClient(uint32_t client_id, 61 ClientDropReason reason_code) override; 62 }; 63 64 } // namespace secagg 65 } // namespace fcp 66 67 #endif // FCP_SECAGG_SERVER_SECAGG_SERVER_R0_ADVERTISE_KEYS_STATE_H_ 68