Documentation for subscribers

This document refers to Schleuder version 3.2 To read about older versions of Schleuder please see the older docs.

Using a list

Everything you send to foo@hostname will be send to all subscribers, but they will see only certain headers and the body of your email. The selection of these headers can be configured for each list individually by the list-admins.

Getting a list’s public key

Each Schleuder-list replies with its public key to any email sent to foo-sendkey@hostname. E.g. to receive the key for our contact address write an email to team-sendkey@schleuder.org.

Special keywords

Schleuder knows some special keywords that trigger different behaviour. You can e.g. subscribe someone, or resend an email to a non-subscriber using keywords. See a list of available keywords below.

Keywords require that:

Keywords can be repeated within one email at will. Letter case doesn’t matter.

There are two types of keywords: those to enhance messages sent over the list (“list-keywords”), and those to request something from Schleuder (“request-keywords”).

Security

To mitigate replay attacks of emails containing keywords, every email using a keyword must contain the special x-list-name keyword followed by the list’s emailaddress. Example:

x-list-name: someone@example.org
You must always provide this keyword once per email. Without it, no other keyword will be considered but you will receive an error message.

Resending

The resending-keywords must be included in messages sent to the normal list-address: foo@hostname.

x-resend: someone@example.org
Send the message to the given address, encrypted if possible, otherwise in the clear.
x-resend-encrypted-only: someone@example.org
Send the message to the given address only if it could be encrypted. Can be abbreviated to x-resend-enc.
x-resend-unencrypted: someone@example.org
Send the message to the given address without encrypting it. You can use this keyword to make schleuder skip looking for a matching key for this address and enforce sending the email out in the clear.
x-resend-cc: someone@example.org anotherperson@example.org
Send one message to all of the given addresses in Cc, so they get to know of each other (encrypted if possible, otherwise in the clear).
x-resend-cc-encrypted-only: someone@example.org
Send one message to all of the given addresses in Cc, so they get to know of each other, only if it could be encrypted to all of those addresses. Can be abbreviated to x-resend-cc-enc.
x-resend-cc-unencrypted: someone@example.org
Send one unencrypted message to all of the given addresses in Cc, so they get to know of each other. We skip looking for any key and will just send out the email in the clear.

Contact list-owner

Write to foo-owner@hostname to contact the list-owner(s) even if you don’t know who they are. Use the list’s key to encrypt the email!

Changed behaviour

Changes to the previous version of Schleuder are summarized in changes.