/* gpgme.js - Javascript integration for gpgme
* Copyright (C) 2018 Bundesamt für Sicherheit in der Informationstechnik
*
* This file is part of GPGME.
*
* GPGME is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* GPGME is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, see <https://www.gnu.org/licenses/>.
* SPDX-License-Identifier: LGPL-2.1+
*
* Author(s):
* Maximilian Krambach <mkrambach@intevation.de>
*/
/* global chrome */
import { permittedOperations } from './permittedOperations';
import { gpgme_error } from './Errors';
import { GPGME_Message, createMessage } from './Message';
import { decode, atobArray, Utf8ArrayToStr } from './Helpers';
/**
* A Connection handles the nativeMessaging interaction via a port. As the
* protocol only allows up to 1MB of message sent from the nativeApp to the
* browser, the connection will stay open until all parts of a communication
* are finished. For a new request, a new port will open, to avoid mixing
* contexts.
* @class
* @private
*/
export class Connection{
constructor (){
this._connection = chrome.runtime.connectNative('gpgmejson');
}
/**
* Immediately closes an open port.
*/
disconnect () {
if (this._connection){
this._connection.disconnect();
this._connection = null;
}
}
/**
* @typedef {Object} backEndDetails
* @property {String} gpgme Version number of gpgme
* @property {Array<Object>} info Further information about the backend
* and the used applications (Example:
* <pre>
* {
* "protocol": "OpenPGP",
* "fname": "/usr/bin/gpg",
* "version": "2.2.6",
* "req_version": "1.4.0",
* "homedir": "default"
* }
* </pre>
*/
/**
* Retrieves the information about the backend.
* @param {Boolean} details (optional) If set to false, the promise will
* just return if a connection was successful.
* @param {Number} timeout (optional)
* @returns {Promise<backEndDetails>|Promise<Boolean>} Details from the
* backend
* @async
*/
checkConnection (details = true, timeout = 1000){
if (typeof timeout !== 'number' && timeout <= 0) {
timeout = 1000;
}
const msg = createMessage('version');
if (details === true) {
return this.post(msg);
} else {
let me = this;
return new Promise(function (resolve) {
Promise.race([
me.post(msg),
new Promise(function (resolve, reject){
setTimeout(function (){
reject(gpgme_error('CONN_TIMEOUT'));
}, timeout);
})
]).then(function (){ // success
resolve(true);
}, function (){ // failure
resolve(false);
});
});
}
}
/**
* Sends a {@link GPGME_Message} via the nativeMessaging port. It
* resolves with the completed answer after all parts have been
* received and reassembled, or rejects with an {@link GPGME_Error}.
*
* @param {GPGME_Message} message
* @returns {Promise<*>} The collected answer, depending on the messages'
* operation
* @private
* @async
*/
post (message){
if (!message || !(message instanceof GPGME_Message)){
this.disconnect();
return Promise.reject(gpgme_error(
'PARAM_WRONG', 'Connection.post'));
}
if (message.isComplete() !== true){
this.disconnect();
return Promise.reject(gpgme_error('MSG_INCOMPLETE'));
}
let chunksize = message.chunksize;
const me = this;
return new Promise(function (resolve, reject){
let answer = new Answer(message);
let listener = function (msg) {
if (!msg){
me._connection.onMessage.removeListener(listener);
me._connection.disconnect();
reject(gpgme_error('CONN_EMPTY_GPG_ANSWER'));
} else {
let answer_result = answer.collect(msg);
if (answer_result !== true){
me._connection.onMessage.removeListener(listener);
me._connection.disconnect();
reject(answer_result);
} else {
if (msg.more === true){
me._connection.postMessage({
'op': 'getmore',
'chunksize': chunksize
});
} else {
me._connection.onMessage.removeListener(listener);
me._connection.disconnect();
const message = answer.getMessage();
if (message instanceof Error){
reject(message);
} else {
resolve(message);
}
}
}
}
};
me._connection.onMessage.addListener(listener);
if (permittedOperations[message.operation].pinentry){
return me._connection.postMessage(message.message);
} else {
return Promise.race([
me._connection.postMessage(message.message),
function (resolve, reject){
setTimeout(function (){
me._connection.disconnect();
reject(gpgme_error('CONN_TIMEOUT'));
}, 5000);
}
]).then(function (result){
return result;
}, function (reject){
if (!(reject instanceof Error)) {
me._connection.disconnect();
return gpgme_error('GNUPG_ERROR', reject);
} else {
return reject;
}
});
}
});
}
}
/**
* A class for answer objects, checking and processing the return messages of
* the nativeMessaging communication.
* @private
*/
class Answer{
/**
* @param {GPGME_Message} message
*/
constructor (message){
this._operation = message.operation;
this._expected = message.expected;
this._response_b64 = null;
}
get operation (){
return this._operation;
}
get expected (){
return this._expected;
}
/**
* Adds incoming base64 encoded data to the existing response
* @param {*} msg base64 encoded data.
* @returns {Boolean}
*
* @private
*/
collect (msg){
if (typeof (msg) !== 'object' || !msg.hasOwnProperty('response')) {
return gpgme_error('CONN_UNEXPECTED_ANSWER');
}
if (!this._response_b64){
this._response_b64 = msg.response;
return true;
} else {
this._response_b64 += msg.response;
return true;
}
}
/**
* Decodes and verifies the base64 encoded answer data. Verified against
* {@link permittedOperations}.
* @returns {Object} The readable gpnupg answer
*/
getMessage (){
if (this._response_b64 === null){
return gpgme_error('CONN_UNEXPECTED_ANSWER');
}
let _decodedResponse = JSON.parse(atob(this._response_b64));
let _response = {
format: 'ascii'
};
let messageKeys = Object.keys(_decodedResponse);
let poa = permittedOperations[this.operation].answer;
if (messageKeys.length === 0){
return gpgme_error('CONN_UNEXPECTED_ANSWER');
}
for (let i= 0; i < messageKeys.length; i++){
let key = messageKeys[i];
switch (key) {
case 'type': {
if (_decodedResponse.type === 'error'){
return (gpgme_error('GNUPG_ERROR',
decode(_decodedResponse.msg)));
} else if (poa.type.indexOf(_decodedResponse.type) < 0){
return gpgme_error('CONN_UNEXPECTED_ANSWER');
}
break;
}
case 'base64': {
break;
}
case 'msg': {
if (_decodedResponse.type === 'error'){
return (gpgme_error('GNUPG_ERROR', _decodedResponse.msg));
}
break;
}
default: {
let answerType = null;
if (poa.payload && poa.payload.hasOwnProperty(key)){
answerType = 'p';
} else if (poa.info && poa.info.hasOwnProperty(key)){
answerType = 'i';
}
if (answerType !== 'p' && answerType !== 'i'){
return gpgme_error('CONN_UNEXPECTED_ANSWER');
}
if (answerType === 'i') {
if ( typeof (_decodedResponse[key]) !== poa.info[key] ){
return gpgme_error('CONN_UNEXPECTED_ANSWER');
}
_response[key] = decode(_decodedResponse[key]);
} else if (answerType === 'p') {
if (_decodedResponse.base64 === true
&& poa.payload[key] === 'string'
) {
if (this.expected === 'uint8'){
_response[key] = atobArray(_decodedResponse[key]);
_response.format = 'uint8';
} else if (this.expected === 'base64'){
_response[key] = _decodedResponse[key];
_response.format = 'base64';
} else { // no 'expected'
_response[key] = Utf8ArrayToStr(
atobArray(_decodedResponse[key]));
_response.format = 'string';
}
} else if (poa.payload[key] === 'string') {
_response[key] = _decodedResponse[key];
} else {
// fallthrough, should not be reached
// (payload is always string)
return gpgme_error('CONN_UNEXPECTED_ANSWER');
}
}
break;
} }
}
return _response;
}
}