Blocked contact's messages still appear in Signal Desktop

[dephekt]

• I have searched open and closed issues for duplicates

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Bug description

Messages from a contact blocked in the Signal-Android client are still being delivered to the linked Signal-Desktop client.

Steps to reproduce

1. Alice has Signal-Desktop linked with Signal-Android. Bob has Signal-Android.
2. Alice blocks Bob via Signal-Android privacy settings.
3. Bob sends Alice a Signal message.
4. Bob's message appears on Alice's Signal-Desktop instance but does not appear on her Signal-Android instance.

Actual result:

At least intermittently, some or all of Bob's messages are getting through to Alice's Signal-Desktop despite Bob being blocked in Signal-Android. Bob's messages do not show up on Alice's Signal-Android client.

Expected result:

If Bob is blocked by Alice via Signal-Android, Bob's messages should not be arriving on Alice's Signal-Desktop in the same way Bob's messages no longer appear on Alice's Signal-Android client after blocking Bob.

Platform info

Signal version:
v1.1.0

Operating System:

Windows 7 Professional Service Pack 1, x64
Windows 10 Pro
Issue observed on fresh installs on both platforms.

Linked device version:

Android: v4.14.10

Link to debug log

https://gist.github.com/anonymous/ad74962d1ecb309134876382eda4aa59
The blocked messages are coming from +[REDACTED]427. See line 9961 for the first event at 2018-01-10T13:33:39.437Z.

[scottnonnenberg]

You say that the issue is observed on fresh installs on both platforms, but are the steps exactly as described for each? You say that you have the Desktop install linked before doing the block - was that true for both Windows installs?

What if you toggle the block off then back to on while you have linked desktop devices? Are the messages blocked then?

[dephekt]

Let me try to clarify more: I have had the user blocked for several weeks via the Android app. Later, I linked a never-before-linked Windows 10 desktop instance. After that, I started receiving messages at that desktop instance from the blocked user. Later, for unrelated reasons, I wiped that Windows 10 install and unlinked the desktop instance, then installed Windows 7, installed Signal desktop, linked it with Android and when I open Signal on the desktop, new messages from the blocked user arrive.

I have not yet tried toggling the block off and back on with the desktop instance linked, but I will try that and let you know if I get any more messages from the blocked user. My expectation was that if the user is blocked in Android that future linked instances of the desktop app would inherit the blocked users from the parent Android instance. The Android instance remains the same throughout desktop OS reinstalls; only the desktop side is changing.

I reinstall operating systems relatively often and unlink them from Android when I do. I have never seen blocked messages arrive on a Linux desktop instance, for what it's worth. I will do some testing with someone I still communicate with so I can more easily isolate the behavior.

[scottnonnenberg]

We have a known weakness in our blocking support. When a desktop instance is first linked, it gets a list of all of your contacts - but that does NOT include blocking status. Only a change to your blocking status (add user, remove user, flip back and forth) on your mobile device will cause that blocking information to be sync'd to your new desktop instance.

Based on what you've described, it seems like that's what's happening. If you see anything that doesn't fit that pattern, please let us know. I'm inclined to change this to a feature request (or dupe it to an existing feature request, if we have one).

[dephekt]

What you described sounds like what I'm seeing; thank you for the information.

You carefully referred to this a 'weakness', but it's clearly a failure in how blocking or syncing is currently implemented and counter-intuitive to the behavior anyone would expect from the block functionality. Having to go through a block list on the phone, unblock every user and re-block them to propagate the block every time one links a new device is clearly a tedious workaround to what most people would call a flaw or bug. Webster's dictionary defines a bug as "an unexpected defect, fault, flaw, or imperfection."

Obviously it's your prerogative to downgrade this to a feature request if you truly don't consider this a flaw and I won't take up further time debating semantics. Thanks again for the update and the work you put in on Signal.

[Alexeyan]

I still have this problem with the most recent Signal Android + Signal Desktop on Windows 10.
@scottnonnenberg-signal @scottnonnenberg

[jh4c]

Also experiencing this on iOS/MacOS. Fresh installs of the latest versions, blocked in iOS before installing the desktop client. On reading this, I attempted the unblock/reblock trick but no change was observed in their status in the desktop client. Why is there not a Block option in the desktop client anyway?

[scottnonnenberg-signal]

@Alexeyan @jh4c What version of SIgnal Desktop are you on? A change went into v1.29.0 to request the block list during link (and generally more often): e9f08c3#diff-b122a16be9feb50ca6509dc7fc088eb0