1 /* 2 * Copyright (C) 2019 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 <stdint.h> 20 21 #include <vector> 22 23 namespace aidl { 24 namespace android { 25 namespace hardware { 26 namespace rebootescrow { 27 namespace hadamard { 28 29 constexpr auto BYTE_LENGTH = 8u; 30 constexpr auto CODEWORD_BYTES = 2u; // uint16_t 31 constexpr auto CODEWORD_BITS = CODEWORD_BYTES * BYTE_LENGTH; 32 constexpr uint32_t CODE_K = CODEWORD_BITS - 1; 33 constexpr uint32_t ENCODE_LENGTH = 1u << CODE_K; 34 constexpr auto KEY_CODEWORD_BYTES = 2u; // uint16_t (after transpose) 35 constexpr auto KEY_CODEWORDS = KEY_CODEWORD_BYTES * BYTE_LENGTH; 36 constexpr auto KEY_SIZE_IN_BYTES = KEY_CODEWORDS * CODEWORD_BYTES; 37 constexpr auto OUTPUT_SIZE_BYTES = ENCODE_LENGTH * KEY_CODEWORD_BYTES; 38 39 // Encodes a key that has a size of KEY_SIZE_IN_BYTES. Returns a byte array representation of the 40 // encoded bitset. So a 32 bytes key will expand to 16*(2^15) bits = 64KiB. 41 std::vector<uint8_t> EncodeKey(const std::vector<uint8_t>& input); 42 43 // Given a byte array representation of the encoded keys, decodes it and return the result. 44 std::vector<uint8_t> DecodeKey(const std::vector<uint8_t>& encoded); 45 46 } // namespace hadamard 47 } // namespace rebootescrow 48 } // namespace hardware 49 } // namespace android 50 } // namespace aidl 51