From: usura@vox.hacktic.nl (Usura)
Date: Fri, 10 Jun 94 08:22:57 PDT
To: cypherpunks@toad.com
Subject: Re: Remailer Chaining Security? [LONG]
Message-ID: <7VPPNc1w165w@vox.hacktic.nl>
MIME-Version: 1.0
Content-Type: text/plain



:But how does one go about chaining through the remailers? I tried this 
:and the message got lost. If indeed you can, does it just involve using 
:more than one (anon-to) line in the header?

Note-1: [R-R-T: stands for Request-Remailing-To: ]
Note-2: [You is in this doc abraxas@cyberspace.org, 
         substitute that adress for own if you want 
         to receive the test message yourself]


First you should test only one remailer:

you > remailer 1 > RRT- you


This is what you send:
--
    TO: remailer@jpunix.com
    
    ::
    Request-Remailing-To: abraxas@cyberspace.org
    
    Test of remailer at jpunix.com
------------------------------------------------
        

This is what you receive:
--
        You will receive this message from jpunix.com
        
        From: remailer@jpunix.com
        To: abraxas@cyberspace.org
        
        Test of remailer at jpunix.com
--

If this is succesful you add another remailer:

you > remailer 2 > RRT- rem 2 >> RRT you


This is what you send:
---
    TO: remailer@jpunix.com
    
    ::
    Request-Remailing-To: nobody@kaiwan.com
    
    ::
    Request-Remailing-To: abraxas@cyberspace.org
    
    Test of remailer at jpunix.com and RRT kaiwan.com
-----------------------------------------------------


        Remailer nobody@kaiwan.com will receive this message from
        remailer@jpunix.com
------    
        From: remailer@jpunix.com
        To: nobody@kaiwan.com
        
        ::
        Request-Remailing-To: abraxas@cyberspace.org
        
        Test of remailer at jpunix.com and RRT kaiwan.com
------

    Because the message has the header pasting tokens [::] 
    the remailer at kaiwan.com knows where to send it to.
    
        You will receive this message from kaiwan.com
        
        From: nobody@kaiwan.com
        To: abraxas@cyberspace.org
        
        Test of remailer at jpunix.com and RRT kaiwan.com
---------------------------------------------------------
You can keep adding remailer this way, everytime you receive
a test message back you add another remailer: if you stop receiving
test messages, the last remailer added is most likely "down". You can
check that by using that remailer directly.

---------------------------------------------------------

The above is simple unencrypted remailing. If you want to have an
encrypted chained remailing, you first have to "design" the chain.

    1] send to jpunix.com there RRT kaiwan.com
    2] at kaiwan.com RRT vox.hacktic.nl
    3] at vox.hacktic.nl RRT abraxas@cyberspace.org
    

First you make the 3rd stage:


--
    ::
    Request-Remailing-To: abraxas@cyberspace.org
    
    Test of PGP'ed remailing trough jpunix, kaiwan and vox.
--

The above is encrypted whit the PGPpubKEY of VoX.hacktic.nl and will
result in this:

-----BEGIN PGP MESSAGE-----
Version: 2.6 for VoX Labz.

hIwCWd90FI1WkT0BA/9I6ILVhl5ZpsgKgHye+ng9CokwzdW1pMgcd0ecigppAODe
53LlyVw/hl1ERYIzWW9W4vnuh7sLgu9XjxB515FtT5VSyZLZrhKIF7XtACga2On+
1NmsecLTrgXYcc4k0Y+l66Hs06z92yhFvjXruDBS2Pame0VDtgZo+4aPntioDaYA
AABJsVIWRaJkCib+uek9Pr6GqFP7lwaMqq8XFnFxY42h3Wn3c5DikrzmwKGK5xVs
hmiZnEhJgXvR7jS2cNNOk/geG4SnUqvMTzpq6w==
=b0bT
-----END PGP MESSAGE-----

--    
    
Then you than proceed to the 2nd stage the message wich has to leave
kaiwan.com:

::
Encrypted: PGP

-----BEGIN PGP MESSAGE-----
Version: 2.6 for VoX Labz.

hIwCWd90FI1WkT0BA/9I6ILVhl5ZpsgKgHye+ng9CokwzdW1pMgcd0ecigppAODe
53LlyVw/hl1ERYIzWW9W4vnuh7sLgu9XjxB515FtT5VSyZLZrhKIF7XtACga2On+
1NmsecLTrgXYcc4k0Y+l66Hs06z92yhFvjXruDBS2Pame0VDtgZo+4aPntioDaYA
AABJsVIWRaJkCib+uek9Pr6GqFP7lwaMqq8XFnFxY42h3Wn3c5DikrzmwKGK5xVs
hmiZnEhJgXvR7jS2cNNOk/geG4SnUqvMTzpq6w==
=b0bT
-----END PGP MESSAGE-----


But kaiwan.com has to know where to send it to, so the 2nd stage msg is:


::
Request-Remailing-To: remail@vox.hacktic.nl

::
Encrypted: PGP

-----BEGIN PGP MESSAGE-----
Version: 2.6 for VoX Labz.

hIwCWd90FI1WkT0BA/9I6ILVhl5ZpsgKgHye+ng9CokwzdW1pMgcd0ecigppAODe
53LlyVw/hl1ERYIzWW9W4vnuh7sLgu9XjxB515FtT5VSyZLZrhKIF7XtACga2On+
1NmsecLTrgXYcc4k0Y+l66Hs06z92yhFvjXruDBS2Pame0VDtgZo+4aPntioDaYA
AABJsVIWRaJkCib+uek9Pr6GqFP7lwaMqq8XFnFxY42h3Wn3c5DikrzmwKGK5xVs
hmiZnEhJgXvR7jS2cNNOk/geG4SnUqvMTzpq6w==
=b0bT
-----END PGP MESSAGE-----

    
The above is then encrypted whit the PGPpubKEY of kaiwan.com:

--
Stage 1:

This new encrypted message gets the headers for jpunix to remail:


::
Request-Remailing-To: nobody@kaiwan.com

::
Encrypted: PGP

-----BEGIN PGG MESSAGE-----

and the PGP encrypted message from stage 2

-----END PGP MESSAGE-----

---

Stage 0: the message you send to jpunix.com

is the encrypted message [with the PGPpubKEY of jpunix.com] of
stage 1 plus a Encrypted: PGP header.


To: remail@jpunix.com

::
Encrypted: PGP

-----BEGIN PGG MESSAGE-----

and the PGP encrypted message from stage 1

-----END PGP MESSAGE-----


--
Exit! Stage Left.
Alex de Joode                                 <usura@vox.hacktic.nl>