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"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.decodeRecoveryKey = decodeRecoveryKey;
exports.encodeRecoveryKey = encodeRecoveryKey;
var _bs = _interopRequireDefault(require("bs58"));
function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
/*
* Copyright 2024 The Matrix.org Foundation C.I.C.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// picked arbitrarily but to try & avoid clashing with any bitcoin ones
// (which are also base58 encoded, but bitcoin's involve a lot more hashing)
const OLM_RECOVERY_KEY_PREFIX = [0x8b, 0x01];
const KEY_SIZE = 32;
/**
* Encode a recovery key using the Matrix {@link https://spec.matrix.org/v1.11/appendices/#cryptographic-key-representation | Cryptographic key representation}
* @param key
*/
function encodeRecoveryKey(key) {
const buf = Buffer.alloc(OLM_RECOVERY_KEY_PREFIX.length + key.length + 1);
buf.set(OLM_RECOVERY_KEY_PREFIX, 0);
buf.set(key, OLM_RECOVERY_KEY_PREFIX.length);
let parity = 0;
for (let i = 0; i < buf.length - 1; ++i) {
parity ^= buf[i];
}
buf[buf.length - 1] = parity;
const base58key = _bs.default.encode(buf);
return base58key.match(/.{1,4}/g)?.join(" ");
}
/**
* Decode a recovery key encoded with the Matrix {@link https://spec.matrix.org/v1.11/appendices/#cryptographic-key-representation | Cryptographic key representation} encoding.
* @param recoveryKey
*/
function decodeRecoveryKey(recoveryKey) {
const result = _bs.default.decode(recoveryKey.replace(/ /g, ""));
let parity = 0;
for (const b of result) {
parity ^= b;
}
if (parity !== 0) {
throw new Error("Incorrect parity");
}
for (let i = 0; i < OLM_RECOVERY_KEY_PREFIX.length; ++i) {
if (result[i] !== OLM_RECOVERY_KEY_PREFIX[i]) {
throw new Error("Incorrect prefix");
}
}
if (result.length !== OLM_RECOVERY_KEY_PREFIX.length + KEY_SIZE + 1) {
throw new Error("Incorrect length");
}
return Uint8Array.from(result.slice(OLM_RECOVERY_KEY_PREFIX.length, OLM_RECOVERY_KEY_PREFIX.length + KEY_SIZE));
}