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metamask-extension/app/scripts/lib/decrypt-message-manager.js

343 lines
12 KiB
JavaScript

import EventEmitter from 'events';
import { ObservableStore } from '@metamask/obs-store';
import { bufferToHex, stripHexPrefix } from 'ethereumjs-util';
import { ethErrors } from 'eth-rpc-errors';
import log from 'loglevel';
import { MESSAGE_TYPE } from '../../../shared/constants/app';
import { EVENT } from '../../../shared/constants/metametrics';
import { METAMASK_CONTROLLER_EVENTS } from '../metamask-controller';
import createId from '../../../shared/modules/random-id';
import { addHexPrefix } from './util';
const hexRe = /^[0-9A-Fa-f]+$/gu;
/**
* Represents, and contains data about, an 'eth_decrypt' type decryption request. These are created when a
* decryption for an eth_decrypt call is requested.
*
* @typedef {object} DecryptMessage
* @property {number} id An id to track and identify the message object
* @property {object} msgParams The parameters to pass to the decryptMessage method once the decryption request is
* approved.
* @property {object} msgParams.metamaskId Added to msgParams for tracking and identification within MetaMask.
* @property {string} msgParams.data A hex string conversion of the raw buffer data of the decryption request
* @property {number} time The epoch time at which the this message was created
* @property {string} status Indicates whether the decryption request is 'unapproved', 'approved', 'decrypted' or 'rejected'
* @property {string} type The json-prc decryption method for which a decryption request has been made. A 'Message' will
* always have a 'eth_decrypt' type.
*/
export default class DecryptMessageManager extends EventEmitter {
/**
* Controller in charge of managing - storing, adding, removing, updating - DecryptMessage.
*
* @param {object} opts - Controller options
* @param {Function} opts.metricEvent - A function for emitting a metric event.
*/
constructor(opts) {
super();
this.memStore = new ObservableStore({
unapprovedDecryptMsgs: {},
unapprovedDecryptMsgCount: 0,
});
this.messages = [];
this.metricsEvent = opts.metricsEvent;
}
/**
* A getter for the number of 'unapproved' DecryptMessages in this.messages
*
* @returns {number} The number of 'unapproved' DecryptMessages in this.messages
*/
get unapprovedDecryptMsgCount() {
return Object.keys(this.getUnapprovedMsgs()).length;
}
/**
* A getter for the 'unapproved' DecryptMessages in this.messages
*
* @returns {object} An index of DecryptMessage ids to DecryptMessages, for all 'unapproved' DecryptMessages in
* this.messages
*/
getUnapprovedMsgs() {
return this.messages
.filter((msg) => msg.status === 'unapproved')
.reduce((result, msg) => {
result[msg.id] = msg;
return result;
}, {});
}
/**
* Creates a new DecryptMessage with an 'unapproved' status using the passed msgParams. this.addMsg is called to add
* the new DecryptMessage to this.messages, and to save the unapproved DecryptMessages from that list to
* this.memStore.
*
* @param {object} msgParams - The params for the eth_decrypt call to be made after the message is approved.
* @param {object} [req] - The original request object possibly containing the origin
* @returns {Promise<Buffer>} The raw decrypted message contents
*/
addUnapprovedMessageAsync(msgParams, req) {
return new Promise((resolve, reject) => {
if (!msgParams.from) {
reject(new Error('MetaMask Decryption: from field is required.'));
return;
}
const msgId = this.addUnapprovedMessage(msgParams, req);
this.once(`${msgId}:finished`, (data) => {
switch (data.status) {
case 'decrypted':
resolve(data.rawData);
return;
case 'rejected':
reject(
ethErrors.provider.userRejectedRequest(
'MetaMask Decryption: User denied message decryption.',
),
);
return;
case 'errored':
reject(new Error('This message cannot be decrypted'));
return;
default:
reject(
new Error(
`MetaMask Decryption: Unknown problem: ${JSON.stringify(
msgParams,
)}`,
),
);
}
});
});
}
/**
* Creates a new DecryptMessage with an 'unapproved' status using the passed msgParams. this.addMsg is called to add
* the new DecryptMessage to this.messages, and to save the unapproved DecryptMessages from that list to
* this.memStore.
*
* @param {object} msgParams - The params for the eth_decryptMsg call to be made after the message is approved.
* @param {object} [req] - The original request object possibly containing the origin
* @returns {number} The id of the newly created DecryptMessage.
*/
addUnapprovedMessage(msgParams, req) {
log.debug(
`DecryptMessageManager addUnapprovedMessage: ${JSON.stringify(
msgParams,
)}`,
);
// add origin from request
if (req) {
msgParams.origin = req.origin;
}
msgParams.data = this.normalizeMsgData(msgParams.data);
// create txData obj with parameters and meta data
const time = new Date().getTime();
const msgId = createId();
const msgData = {
id: msgId,
msgParams,
time,
status: 'unapproved',
type: MESSAGE_TYPE.ETH_DECRYPT,
};
this.addMsg(msgData);
// signal update
this.emit('update');
return msgId;
}
/**
* Adds a passed DecryptMessage to this.messages, and calls this._saveMsgList() to save the unapproved DecryptMessages from that
* list to this.memStore.
*
* @param {Message} msg - The DecryptMessage to add to this.messages
*/
addMsg(msg) {
this.messages.push(msg);
this._saveMsgList();
}
/**
* Returns a specified DecryptMessage.
*
* @param {number} msgId - The id of the DecryptMessage to get
* @returns {DecryptMessage|undefined} The DecryptMessage with the id that matches the passed msgId, or undefined
* if no DecryptMessage has that id.
*/
getMsg(msgId) {
return this.messages.find((msg) => msg.id === msgId);
}
/**
* Approves a DecryptMessage. Sets the message status via a call to this.setMsgStatusApproved, and returns a promise
* with the message params modified for proper decryption.
*
* @param {object} msgParams - The msgParams to be used when eth_decryptMsg is called, plus data added by MetaMask.
* @param {object} msgParams.metamaskId - Added to msgParams for tracking and identification within MetaMask.
* @returns {Promise<object>} Promises the msgParams object with metamaskId removed.
*/
approveMessage(msgParams) {
this.setMsgStatusApproved(msgParams.metamaskId);
return this.prepMsgForDecryption(msgParams);
}
/**
* Sets a DecryptMessage status to 'approved' via a call to this._setMsgStatus.
*
* @param {number} msgId - The id of the DecryptMessage to approve.
*/
setMsgStatusApproved(msgId) {
this._setMsgStatus(msgId, 'approved');
}
/**
* Sets a DecryptMessage status to 'decrypted' via a call to this._setMsgStatus and updates that DecryptMessage in
* this.messages by adding the raw decryption data of the decryption request to the DecryptMessage
*
* @param {number} msgId - The id of the DecryptMessage to decrypt.
* @param {buffer} rawData - The raw data of the message request
*/
setMsgStatusDecrypted(msgId, rawData) {
const msg = this.getMsg(msgId);
msg.rawData = rawData;
this._updateMsg(msg);
this._setMsgStatus(msgId, 'decrypted');
}
/**
* Removes the metamaskId property from passed msgParams and returns a promise which resolves the updated msgParams
*
* @param {object} msgParams - The msgParams to modify
* @returns {Promise<object>} Promises the msgParams with the metamaskId property removed
*/
prepMsgForDecryption(msgParams) {
delete msgParams.metamaskId;
return Promise.resolve(msgParams);
}
/**
* Sets a DecryptMessage status to 'rejected' via a call to this._setMsgStatus.
*
* @param {number} msgId - The id of the DecryptMessage to reject.
* @param reason
*/
rejectMsg(msgId, reason = undefined) {
if (reason) {
this.metricsEvent({
event: reason,
category: EVENT.CATEGORIES.MESSAGES,
properties: {
action: 'Decrypt Message Request',
},
});
}
this._setMsgStatus(msgId, 'rejected');
}
/**
* Sets a TypedMessage status to 'errored' via a call to this._setMsgStatus.
*
* @param {number} msgId - The id of the TypedMessage to error
* @param error
*/
errorMessage(msgId, error) {
const msg = this.getMsg(msgId);
msg.error = error;
this._updateMsg(msg);
this._setMsgStatus(msgId, 'errored');
}
/**
* Clears all unapproved messages from memory.
*/
clearUnapproved() {
this.messages = this.messages.filter((msg) => msg.status !== 'unapproved');
this._saveMsgList();
}
/**
* Updates the status of a DecryptMessage in this.messages via a call to this._updateMsg
*
* @private
* @param {number} msgId - The id of the DecryptMessage to update.
* @param {string} status - The new status of the DecryptMessage.
* @throws A 'DecryptMessageManager - DecryptMessage not found for id: "${msgId}".' if there is no DecryptMessage
* in this.messages with an id equal to the passed msgId
* @fires An event with a name equal to `${msgId}:${status}`. The DecryptMessage is also fired.
* @fires If status is 'rejected' or 'decrypted', an event with a name equal to `${msgId}:finished` is fired along
* with the DecryptMessage
*/
_setMsgStatus(msgId, status) {
const msg = this.getMsg(msgId);
if (!msg) {
throw new Error(
`DecryptMessageManager - Message not found for id: "${msgId}".`,
);
}
msg.status = status;
this._updateMsg(msg);
this.emit(`${msgId}:${status}`, msg);
if (
status === 'rejected' ||
status === 'decrypted' ||
status === 'errored'
) {
this.emit(`${msgId}:finished`, msg);
}
}
/**
* Sets a DecryptMessage in this.messages to the passed DecryptMessage if the ids are equal. Then saves the
* unapprovedDecryptMsgs index to storage via this._saveMsgList
*
* @private
* @param {DecryptMessage} msg - A DecryptMessage that will replace an existing DecryptMessage (with the same
* id) in this.messages
*/
_updateMsg(msg) {
const index = this.messages.findIndex((message) => message.id === msg.id);
if (index !== -1) {
this.messages[index] = msg;
}
this._saveMsgList();
}
/**
* Saves the unapproved DecryptMessages, and their count, to this.memStore
*
* @private
* @fires 'updateBadge'
*/
_saveMsgList() {
const unapprovedDecryptMsgs = this.getUnapprovedMsgs();
const unapprovedDecryptMsgCount = Object.keys(unapprovedDecryptMsgs).length;
this.memStore.updateState({
unapprovedDecryptMsgs,
unapprovedDecryptMsgCount,
});
this.emit(METAMASK_CONTROLLER_EVENTS.UPDATE_BADGE);
}
/**
* A helper function that converts raw buffer data to a hex, or just returns the data if it is already formatted as a hex.
*
* @param {any} data - The buffer data to convert to a hex
* @returns {string} A hex string conversion of the buffer data
*/
normalizeMsgData(data) {
try {
const stripped = stripHexPrefix(data);
if (stripped.match(hexRe)) {
return addHexPrefix(stripped);
}
} catch (e) {
log.debug(`Message was not hex encoded, interpreting as utf8.`);
}
return bufferToHex(Buffer.from(data, 'utf8'));
}
}