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                     ngIRCd - Next Generation IRC Server

                        (c)2001-2008 Alexander Barton,
                    alex@barton.de, http://www.barton.de/

               ngIRCd is free software and published under the
                   terms of the GNU General Public License.

                                 -- SSL.txt --


ngIRCd supports SSL/TLSv1 encrypted connections using the OpenSSL or GnuTLS
libraries. Both encrypted server-server links as well as client-server links
are supported.

SSL is a compile-time option which is disabled by default. Use one of these
options of the ./configure script to enable it:

  --with-openssl     enable SSL support using OpenSSL
  --with-gnutls      enable SSL support using GnuTLS

You also need a key/certificate, see below for how to create a self-signed one.

From a feature point of view, ngIRCds support for both libraries is
comparable. The only major difference (at this time) is that ngircd with gnutls
does not support password protected private keys.

Configuration
~~~~~~~~~~~~~

To enable SSL connections a separate port must be configured: it is NOT
possible to handle unencrypted and encrypted connections on the same port!
This is a limitation of the IRC protocol ...

You have to set (at least) the following configuration variables in the
[SSL] section of ngircd.conf(5): Ports, KeyFile, and CertFile.

Now IRC clients are able to connect using SSL on the configured port(s).
(Using port 6697 for encrypted connections is common.)

To enable encrypted server-server links, you have to additionally set
SSLConnect to "yes" in the corresponding [SERVER] section.


Creating a self-signed certificate
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

OpenSSL:

Creating a self-signed certificate and key:
 $ openssl req -newkey rsa:2048 -x509 -keyout server-key.pem -out server-cert.pem -days 1461
Create DH parameters (optional):
 $ openssl dhparam -2 -out dhparams.pem 4096

GnuTLS:

Creating a self-signed certificate and key:
 $ certtool --generate-privkey --bits 2048 --outfile server-key.pem
 $ certtool --generate-self-signed --load-privkey server-key.pem --outfile server-cert.pem
Create DH parameters (optional):
 $ certtool  --generate-dh-params --bits 4096 --outfile dhparams.pem


Alternate approach using stunnel(1)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Alternatively (or if you are using ngIRCd compiled without support
for GnuTLS/OpenSSL), you can use external programs/tools like stunnel(1) to
get SSL encrypted connections:

  <http://stunnel.mirt.net/>
  <http://www.stunnel.org/>

Stefan Sperling (stefan at binarchy dot net) mailed the following text as a
short "how-to", thanks Stefan!

=== snip ===
    ! This guide applies to stunnel 4.x !

    Put this in your stunnel.conf:

        [ircs]
        accept = 6667
        connect = 6668

    This makes stunnel listen for incoming connections
    on port 6667 and forward decrypted data to port 6668.
    We call the connection 'ircs'. Stunnel will use this
    name when logging connection attempts via syslog.
    You can also use the name in /etc/hosts.{allow,deny}
    if you run tcp-wrappers.

    To make sure ngircd is listening on the port where
    the decrypted data arrives, set

        Ports = 6668

    in your ngircd.conf.

    Start stunnel and restart ngircd.

    That's it.
    Don't forget to activate ssl support in your irc client ;)
    The main drawback of this approach compared to using builtin ssl
    is that from ngIRCds point of view, all ssl-enabled client connections will
    originate from the host running stunnel.
=== snip ===