Skip to content

Add fix for event security (MessageEvent source issue) #79

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
david0xd merged 3 commits into from
Mar 7, 2023
Merged

Add fix for event security (MessageEvent source issue) #79

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
9c1061f
Add fix for event security (MessageEvent source issue)
david0xd Mar 2, 2023
ef1b439
Refactor (remove ts-expect-error and add assertions)
david0xd Mar 3, 2023
b3d2500
Refactor (review proposal)
david0xd Mar 6, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
22 changes: 20 additions & 2 deletions src/window/WindowPostMessageStream.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,3 +1,4 @@
import { assert } from '@metamask/utils';
import {
BasePostMessageStream,
PostMessageEvent,
Expand All @@ -11,6 +12,20 @@ interface WindowPostMessageStreamArgs {
targetWindow?: Window;
}

/* istanbul ignore next */
const getSource = Object.getOwnPropertyDescriptor(
MessageEvent.prototype,
'source',
)?.get;
assert(getSource, 'MessageEvent.prototype.source getter is not defined.');

/* istanbul ignore next */
const getOrigin = Object.getOwnPropertyDescriptor(
MessageEvent.prototype,
'origin',
)?.get;
assert(getOrigin, 'MessageEvent.prototype.origin getter is not defined.');

/**
* A {@link Window.postMessage} stream.
*/
Expand Down Expand Up @@ -77,14 +92,17 @@ export class WindowPostMessageStream extends BasePostMessageStream {
private _onMessage(event: PostMessageEvent): void {
const message = event.data;

/* eslint-disable @typescript-eslint/no-non-null-assertion */
if (
(this._targetOrigin !== '*' && event.origin !== this._targetOrigin) ||
event.source !== this._targetWindow ||
(this._targetOrigin !== '*' &&
getOrigin!.call(event) !== this._targetOrigin) ||
getSource!.call(event) !== this._targetWindow ||
!isValidStreamMessage(message) ||
message.target !== this._name
) {
return;
}
/* eslint-enable @typescript-eslint/no-non-null-assertion */

this._onData(message.data);
}
Expand Down