No E2EE with new contact via invite link -- permanent SMTP error

I recommended Delta Chat to a friend, he sent me his invite link via SMS, but chat does not work.

After clicking the invite link, the new chat opened with the chosen user name of my friend at the top.

Program said: “Establishing guaranteed end-to-end encryption, please wait…”

Then: “Could not yet establish guaranteed end-to-end encryption, but you may already send a message.”

Which I did. The message is showing an exclamation mark, and when I tap on it, a dialogue appears: “Error – Permanent SMTP error: permanent: Encryption Needed: Invalid Unencrypted Mail”

Delta Chat version

Version 1.56.1 (downloaded today from the Delta Chat website and sideloaded in Android)

Expected behavior

I would expect that the contact is established and that we can chat securely.

Actual behavior

See above. No E2EE, with permanent SMTP error. Chat is not established, despite program claiming that I “may already send a message”.

I tapped on the invite link a second time, with same result.

Steps to reproduce the problem

  1. Open invite link.
  2. Try to chat.

Screen snapshots

Not necessary, I think.

Debug logs

I cannot copy a debug log in the manner described below, tapping on version number gets me to the Help. Is this outdated?

“If applicable, debug logs can be copied from within the Delta Chat app: Open the Settings menu → Aboutversion number|Info.”

Hi :wave:, which email providers do you both use?

Hi Raiden, we both use nine.testrun.org.

In the meantime I’ve MMS’ed my QR code to my friend. He’s loaded it in DC, and now it works! (All my previous contacts I’ve made via QR, there was never a problem.)

It will still be useful to solve the invite link problem. At least for me.

It is this bug: secure-join timeout is not useful for chatmail · Issue #6706 · chatmail/core · GitHub

“You may already send a message.” info message does not make sense when the server is enforcing encryption and is going to be replaced.

See also:

Hey link2xt, I see, so that message about already being able to send messages despite lack of encryption has no meaning. Thanks!

The message is from the time when there were no chatmail servers that enforce encryption and Delta Chat was mostly used over normal email servers. In this case you can send a message without waiting, but it is sent unencrypted. We are now changing this to block the chat until E2EE is established and you will only be able to send the message once you have encryption established even with a normal email server.

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@link2txt: Sounds reasonable.

But I would still like to know (and ideally have resolved) why invite links don’t work (or at least that one didn’t) but QR codes do.

Invite links and QR codes work exactly the same way internally.

SecureJoin protocol requests the key over email, so if you are not online at the time when the other user scans the QR code or follows the link, finishing the protocol may take some time. If both users are online it only takes seconds.

What probably happened is that when you clicked the invite link, your contact was not online.

I suspected that the QR code simply encodes the invite link, which made me wonder. Now I understand. Both participants need to be online. Cheers!

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It’s easy for anyone to make this mistake of thinking that E2EE is set up immediately after scanning the QR code or clicking the invite link, so I’m glad this is being addressed and Delta Chat will soon block chats until E2EE is established, to prevent accidental misuse.

Yes, but not necessarily at the same time. You can take turns to be online and it will still work.

I suggested here a way to make this less confusing for new users:

@bencan

Yea, that’s what I actually meant, probably.

Good idea. If the message were like that I wouldn’t have been confused.

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