From: Onion Courier <noreply@oc2mx.net>
Subject: [Bitmessage] A proposal, what do you think?
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Date: Tue, 18 Feb 2025 21:53:41 +0000 (UTC)
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Let's assume Bob travels a lot and does not want to take any devices
with him, including his private keys, email addresses etc., but Alice
wants to be sure that she is communicating securely with Bob, once he
arrived at his various destinations.

Prior his departure they both agreed on (a) shared secret(s) they will use.

First they agree on a secret chan, like this example shows:

[BM-2cVDByPfU25C6txRff2GfDSrxCD1PCm6yx]
label = [chan] 97be230c60497b24a0f42c9835b1002e33a7ca7574d441a10845c285c985c6d3483304278e7a26009ab49dd4d4a7f7532912d4c662011a836f46b7083689146700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000425
enabled = true
decoy = false
chan = true
noncetrialsperbyte = 1000
payloadlengthextrabytes = 1000
privsigningkey = 5K2Vycub1BAfbpsVxjnp8KSjoyXLAwB9hyuT819Nu7WB2Sd9mFx
privencryptionkey = 5KXVcwz7EDXNPnDqYfiHS1SsDjsEazsvpAkHY6oUDb1ZWM9fUNr

The chan was generated with a 1024-bit hex prime number, which is
deterministic. In order to generate such a deterministic prime number
they used https://github.com/706f6c6c7578/dprime

$ dprime -p test -s test -h

So, when Bob arrives at his destination he visits a public library or
Internet Café etc. and downloads the BM-client and dprime from GitHub.
Hopefully these two URLs are not blocked at his destination(s)!

Now since Alice and Bob have a communication channel established they
can additionally use dprime with zkp+ https://github.com/706f6c6c7578/zkp
(with a second shared secret), so that she knows that she is really
communicating with Bob.

Hope you like the idea and that it is not to complicated!