New Feature request: command line to execute before stablishing connections towards the e-mail server

Hello,

Expected behavior

For me it would be very useful the application to have the possibility to store, for every account, an optional field (command line to execute before stablishing the connection towards the email server).

This field would contain a command line which would be executed before trying to connect to the email server.

In my case, this would be useful, because I am planning to use fwknop in the linux server where I will have the email server.

The fwknop functionality gives you the possibility to close all ports of your server until the server receives an appropiate combination of tcp messages. In such a case, the fwknop server would create firewall rules to open the port requested for a few seconds.

In these few seconds, the client can connect to the server because the ports are open.

fwknop2 is an application available in Android as open source code.

I suppose this fwknop2 application could be modified to have the possibility of being invoked to send the fwknop messages from the command line, and then, using the new feature just requested for k-9, open the ports before attemting to connect to the email server.

Actual behavior

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Steps to reproduce

Environment

K-9 Mail version: For new versions

Android version: For all versions

Account type (IMAP, POP3, WebDAV/Exchange): For all account types

P.D. I suppose you are very busy with other implementations. In this case, I could offer my services to try to program this request. Although I am not very familiar with Android, I have quite experience programming with Java and I think I could succeed with this development.

Please, let me know what do you think about it.

Kind regards, Fran. ( [e-mail] )

EDIT: Post formatting changes only (@philipwhiuk)

[philipwhiuk]

It seems like the best strategy is for K-9 to support proxying ( #704 )

So you’d have an Android application on the phone which proxied K-9 connections, sending the appropriate fwknop calls as applicable before opening the connection.

This is broadly how Android applications support, for example, TOR.

I don’t think adding specific settings to inject commands of some form is a good idea.

[philipwhiuk]

I’m going to close this - outside of the linked ticket there’s no additional work to be done by K9 here.