CertFP

As an alternative to password-based authentication, you can connect to freenode with a TLS certificate and have services recognise it automatically.

Creating a self-signed certificate

In order to follow these instructions, you will need the openssl utility. If you are using Windows and do not have a copy, you might consider using Cygwin.

You can generate a certificate with the following command:

openssl req -x509 -new -newkey rsa:4096 -sha256 -days 1000 -nodes -out freenode.pem -keyout freenode.pem

You will be prompted for various pieces of information about the certificate. The contents do not matter for our purposes, but openssl needs at least one of them to be non-empty.

The .pem file will have the same access to your NickServ account as your password does, so take appropriate care in securing it.

Under Unix-like environments, the following command:

openssl x509 -in freenode.pem -outform der | sha1sum -b | cut -d' ' -f1

will list the certificate fingerprint.

Connecting to freenode with your certificate

IRC clients generally differ in where they look for a certificate and how you configure them to offer it to the server. If yours is not yet listed here, advice in this section is unlikely to apply, but guides may be available elsewhere on the web.

irssi

Move the certificates you created above to ~/.irssi/certs

mkdir ~/.irssi/certs
mv freenode.pem ~/.irssi/certs

Now configure your /server entry for freenode to use this certificate. You may need to adapt this example for your existing configuration (the network and hostname should match what you already use).

/server add -auto -ssl -ssl_cert ~/.irssi/certs/freenode.pem -network freenode chat.freenode.net 6697

weechat

Move the certificates you created above to ~/.weechat/certs

mkdir ~/.weechat/certs
mv nick.pem ~/.weechat/certs

Now disconnect and remove the current freenode server(s). Re-add it with the SSL flag, using your newly generated certificate. Note that these commands are just examples, you have to adapt them to your current servers.

/set irc.server.freenode.addresses chat.freenode.net/6697
/set irc.server.freenode.ssl on
/set irc.server.freenode.ssl_verify on
/set irc.server.freenode.ssl_cert %h/certs/nick.pem
/set irc.server.freenode.sasl_mechanism external

and then reconnect to freenode.

znc

Refer to znc's official documentation.

HexChat

The pem file should be placed in certs/network name.pem in the HexChat config directory (~/.config/hexchat/ or %appdata%\HexChat), where network name is the name of the network as it appears in the network list (Ctrl-S). Note that the certs directory does not exist by default and you will have to create it yourself. Once the file is there, all subsequent SSL connections to that network will use the certificate.

Add your fingerprint to NickServ

You can then check whether you have a fingerprint by using whois on yourself:

/whois YourOwnNick
...
YourOwnNick has client certificate fingerprint f3a1aad46ca88e180c25c9c7021a4b3a
...

To allow NickServ to recognise you based on your certificate, you need to add the fingerprint to your account (you will need to log in by other means in order to do so).

You can then authorise your current certificate fingerprint:

/msg NickServ CERT ADD

In the future, any connections you make to freenode with your certificate will be logged into your account automatically. Optionally, or if you wish to connect via Tor, you can enable SASL with the EXTERNAL mechanism.