1993-02-24 - Beware of anon.penet.fi message!

Header Data

From: Eric Hughes <hughes@soda.berkeley.edu>
To: cypherpunks@toad.com
Message Hash: e3818d01c80414fc06292bc14172d7171a5faff1baabdebc1c1024b91366ac30
Message ID: <9302241820.AA11378@soda.berkeley.edu>
Reply To: <9302231921.aa24595@penet.penet.FI>
UTC Datetime: 1993-02-24 18:23:56 UTC
Raw Date: Wed, 24 Feb 93 10:23:56 PST

Raw message

From: Eric Hughes <hughes@soda.berkeley.edu>
Date: Wed, 24 Feb 93 10:23:56 PST
To: cypherpunks@toad.com
Subject: Beware of anon.penet.fi message!
In-Reply-To: <9302231921.aa24595@penet.penet.FI>
Message-ID: <9302241820.AA11378@soda.berkeley.edu>
MIME-Version: 1.0
Content-Type: text/plain

Re: an1234 vs. na1234

Julf writes:
>Now we only have to fight about what the From: line in anonymous
>messages ought to say, an1234 or na1234?

You can determine the From: line by looking at the destination.

If the destination is to another alias, then you use "an1234", since
the reply should appear to be coming from another alias.  Using the
"an1234" address triggers the aliasing mechanism.  

On the other hand, if the destination is to a non-alias mailbox, then
use the "na1234" form.  In this way the alias mechanism is not invoked
upon reply.

For messages with more than one addressee, split all the alias
destinations into one message, and all the non-alias destinations into
another.  Set the From: line accordingly in each message.  This avoids
the attack of using a two-recipient message to invoke an incorrect
alias behavior.

For newsgroup postings, where no particular addressee is listed, and
for mailing lists, I would suggest using "na1234", but this probably
is a change in the default behavior for newsgroups.  You would like
newsgroups and mailing lists to act the same, and that means either
keeping a list of mailing list entry points (ick), or using the
"na1234" form.