Mixmaster 3.0 -- anonymous remailer software -- (C) 1999 - 2000 Anonymizer Inc.
                                  (C) 2000-2014 The Mixmaster Development Team
-------------------------------------------------------------------------------

This program consists of

* a remailer client:

  The remailer client supports sending anonymous mail using Cypherpunk and
  Mixmaster remailers. It supports OpenPGP encryption (compatible with PGP 2,
  PGP 5 and up, and GnuPG).

  The client can be used with a menu-based user interface and with command line
  options.

* a remailer:

  The remailer supports the Cypherpunk and Mixmaster message formats.  It can
  be integrated with the mail delivery system of Unix-based computers or use
  the POP3 and SMTP protocols for mail transfer.  Mixmaster includes an
  automated abuse-handling system.

Please report any problems at alt.privacy.anon-server or
https://github.com/merkinmuffley/mixmaster4096
or remops (http://lists.mixmin.net/pipermail/remops/).


Installation:
------------

Libraries:

  Mixmaster requires the libraries OpenSSL, zlib, and pcre. 
  
  If you want to use the menu-based user interface, you also need the ncurses
  library. If these libraries are not installed on your system, you will need
  to obtain the latest versions from the sources below and extract them in the
  the Src/ directory first.

  OpenSSL is available from http://www.openssl.org/source/

  Ncurses can be obtained from http://ftp.gnu.org/pub/gnu/ncurses/

  The Perl Compatable Regular Expressions library can be obtained from
  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/
  (Red Hat related systems such as CentOS may need the "pcre-devel" package.)

  The zlib compression libraries can be obtained from
  http://www.gzip.org/zlib/

To install or upgrade Mixmaster, type `./Install'.

Mixmaster clients rely on pingers to compile statistics and keyrings for
currently operating remailers.  A list of public pingers can be obtained from
http://www.noreply.org/allpingers/.

Alternatively clients can operate their own pingers to generate statistics.
Pinger software can be obtained from http://www.palfrader.org/echolot/.  If you
choose this option, please publish the pinger results for the benefit of other
Mixmaster users and notify the metastats maintainer at admin@mixmin.net.

The required files published by pingers are:-
  pubring.asc    Type 1 remailer keys
  pubring.mix    Type 2 remailer keys
  rlist.txt      List of reliable type 1 remailers
  mlist.txt      List of reliable type 2 remailers
  type2.list     List of known type 2 remailers (optional)

Using the remailer client:
-------------------------

To use the menu-based user interface, simply run `mixmaster'. To send an
anonymous or pseudonymous reply to a message from within your mail or news
reader, you can pipe it to `mixmaster'.

The interactive mode supports sending mail and contains a simple mail reading
function. OpenPGP messages are encrypted and decrypted automatically. 

In the non-interactive mode, Mixmaster reads a message from a file or from its
standard input. The command line options are described in the manual page
(mixmaster.1).


Mixmaster as a remailer:
-----------------------

The Mixmaster remailer can be installed on any account that can receive mail.
Non-remailer messages will be delivered as usual. If you have root access, you
may want to create a new user (e.g., `remailer') and install Mixmaster under
that user id.

The Install script provides a simple way to set up the remailer. More
information about configuring Mixmaster can be found in the manual page.
Typically, incoming mail is piped to "mixmaster -RM". In a UUCP setting, it may
be useful to use just "mixmaster -R", and run "mixmaster -S" once all messages
have arrived.

Announcing a new remailer to the public is most commonly done by posting the
remailer keys and capabilities to alt.privacy.anon-server as well as the
"remops" mailing list. Information about the remops list can be found here:
http://lists.mixmin.net/mailman/listinfo/remops


Installation problems:
---------------------

In case one of the libraries Mixmaster uses is installed incorrectly on your
system, place the library source code (available from the locations listed
above) in the Src directory, remove the old Makefile, run the Install script
again and answer `y' when asked whether to use the source code.

The ncurses library can use termcap and terminfo databases. The Mixmaster
Install script tries to find out whether terminfo is available. If you get a
"Can't open display" error when starting the Mixmaster menu, run "./configure
--enable-termcap; make lib/libncurses.a" in the ncurses directory.


Security notes:
--------------

The ciphers and the anonymizing mix-net protocol used in Mixmaster correspond
to the state of the art (see the Security Considerations section of the
Mixmaster Protocol specification for details). However, no security proofs
exist for any practical cryptosystem. It is unlikely that their security will
be broken, but there is no "perfect security". Software can also contain
implementation errors. The complete Mixmaster source code is available for
public review, so that everyone can verify what the program does, and it is
unlikely that security related errors or secret back doors in the software
would go unnoticed.

No software is secure if run in an insecure environment. For that reason you
must make sure that there is no malicious software (such as viruses) running on
your computer. Deleted files and even passphrases can in many cases be read
from the hard disk if an adversary has access to the computer. The use of disk
encryption programs is recommended to avoid this risk.

Anonymous messages are secure as long as at least one of the remailers you use
in a chain is honest. You can use up to 20 remailers in a chain, but
reliability and speed decrease with longer chains. Four is a reasonable number
of remailers to use. Many remailer operators sign their keys. You should verify
those signatures with OpenPGP to make sure that you have the actual remailer
keys.

Anonymous keys usually cannot be introduced to the OpenPGP web of trust without
giving up anonymity. For that reason, this client will use any OpenPGP key
found on the key ring, whether it is certified or not. Your key ring must not
contain any invalid keys when used with this program.

If you want to use a pseudonym, the client will ask you for a passphrase to
protect the nym database. Your passphrase should be long, and hard to guess.
Anyone who gets hold of your nym database and private keys and can determine
the passphrase will be able to compromise your pseudonymous identities. Note
that some operating systems may store your passphrase on your hard disk in
clear.

While a good client passphrase can protect your keys if someone gets hold of
your files, the remailer passphrase offers only casual protection for the
remailer keys. If you install a remailer, the remailer passphrase must be
different from your private passphrases.

Note that nym.alias.net style nym-servers are trivially breakable by an
adversary performing a long-term intersection attack. Discussion of 
these attacks can be found in section 4.2 of The Pynchon Gate, by 
Sassaman, Cohen, and Mathewson, 2005. Use of Type I remailers for any 
purpose is discouraged.


Copyright:
---------

Mixmaster may be redistributed and modified under certain conditions.  This
software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND,
either express or implied. See the file COPYRIGHT for details.

A license is required to use the IDEA(TM) algorithm for commercial purposes;
see the file idea.txt for details.

Mixmaster uses the compression library zlib by Jean-loup Gailly and Mark Adler,
the free ncurses library and the regex library by Philip Hazel.  This product
includes cryptographic software written by Eric Young (eay@cryptsoft.com). This
product includes software developed by the OpenSSL Project for use in the
OpenSSL Toolkit (http://www.OpenSSL.org/).  For some platforms: This product
includes software developed by the University of California, Berkeley and its
contributors.

Additionally, this software uses code provided by the members of the 
Mixmaster development team. The members respectively hold the copyright 
to the code in question, having elected to make it available under the 
Mixmaster license.

All trademarks are the property of their respective owners.

$Id$
