Recieved messages with URLs containing unicode don't display

[ethanalker]

Bug description

Sending a link with a unicode character in it causes the message to fail to send. The message shows as delivered on the sender's client, but the reciever sees no message.

Steps to reproduce

• Send a link with unicode in it to an iOS device (https://en.m.wikipedia.org/wiki/Nausicaä_of_the_Valley_of_theWind(film))

Actual result: On the sender's client, the message shows as delivered. On the reciever's client, nothing is shown.

Expected result: The message should appear on the reciever's device.

Additional Notes

• When sending to an andriod device (from iOS) the message is successfully recieved
• When sending from an andriod device (to iOS) the message fails to send, same as iOS to iOS
• This implies the issue is in the code for the reciever in iOS specifically
• The bug does not happen when the URL is percent encoded

Screenshots

Device info

Device: iPhone 13 & iPhone 12 Pro

iOS version: 16.0 (20A362) & 17.5.1

Signal version: 7.25 (287)

Link to debug log

This debug log contains both sending and receiving a bad link, to/from an iOS device. https://debuglogs.org/ios/7.25.0/c7910952c721686b7f127540a16ae0ac5ecd27dfe9e944bc334bbed5e2047aab.zip

[ethanalker]

Looking through the logs again is looks like root of the issue is here and propogates here (corresponding to the two warnings in the logs). This could be caused by a bad string encoding when creating the string, which seems to be coming from the parseStringEncoding function in HTTPURLResponse, so there may be a bug in that function.

[ethanalker]

I didn't track down what code causes the message not to show, but it may be worth finding where that happens and improving the error handling so the message will show in some capcity even if errors like this occur, or at least make it visible to the user that something happened.

I discovered this when I was sent a link and, from my perspective, I was just left on read. This is a bad user experience and shouldn't happen.

[ethanalker]

This was fixed in 7.26 by breaking embeds with URLs containing unicode. I'd have preferred if it escaped automatically and supported the (technically malformed) URLs, since users still sometimes get their hands on these URLs sometimes from e.g. copying from a browser, but a resolution is a resolution. Closing.