Function restorePrivateKeyBackup

src/modules/pgpModel.js:365–387

(armoredBlock, code)

}

export async function restorePrivateKeyBackup(armoredBlock, code) {
  let message = await pgpReadMessage({armoredMessage: armoredBlock});
  if (!(message.packets.length === 2 &&
        message.packets[0].constructor.tag === enums.packet.symEncryptedSessionKey && // Symmetric-Key Encrypted Session Key Packet
        message.packets[0].sessionKeyAlgorithm === enums.symmetric.aes256 &&
        (message.packets[0].sessionKeyEncryptionAlgorithm === null || message.packets[0].sessionKeyEncryptionAlgorithm === enums.symmetric.aes256) &&
        message.packets[1].constructor.tag === enums.packet.symEncryptedIntegrityProtectedData // Sym. Encrypted Integrity Protected Data Packet
  )) {
    throw new MvError('Illegal private key backup structure.');
  }
  try {
    message = await message.decrypt(null, [code], undefined, undefined, {...pgpConfig, additionalAllowedPackets: [SecretKeyPacket, UserIDPacket, SignaturePacket, SecretSubkeyPacket]});
  } catch (e) {
    throw new MvError('Could not decrypt message with this restore code', 'WRONG_RESTORE_CODE');
  }
  // extract password
  const metaInfo = await readToEnd(message.getText());
  const pwd = parseMetaInfo(metaInfo).Pwd;
  // remove literal data packet
  const keyPackets = await readToEnd(message.packets.stream, _ => _);
  const privKey =  new PrivateKey(keyPackets);
  return {key: privKey, password: pwd};
}

/**
 * @param  {openpgp.key.Key} key - key to decrypt and verify signature