Notice: opt-in beta

We are rolling out 2-factor authentication for access to gitolite.kernel.org. At this point, this feature is still in testing stage and will probably always remain opt-in instead of being required across the board.

Once 2-factor authentication is enabled for a git repository, any write operation from an IP address that hasn't been 2-factor validated will be rejected with a message like the following:

remote: User not enrolled with 2-factor authentication.
remote: FATAL: W VREF/2fa: testing mricon DENIED by VREF/2fa
remote: 2-factor verification failed
remote:
remote: You will need to enroll with 2-factor authentication
remote: before you can push to this repository.
remote:
remote: If you need more help, please see the following link:
remote:     https://korg.wiki.kernel.org/index.php?title=Userdoc:gitolite_2fa
remote:
remote: error: hook declined to update refs/heads/master

To allow the push to succeed, you will need to first validate the IP address with your 2-factor token, which will allow all pushes from that IP address to succeed – until the validation expires. The default expiration time is 24 hours, but you may set it to be as long as 30 days.

Examples:

ssh git@gitolite.kernel.org 2fa val XXXXXX
ssh git@gitolite.kernel.org 2fa val-for-days 30 XXXXXX

Read operations should be completely unaffected.

We implement both HOTP (RFC 4226) and TOTP (RFC 6238) parts of the OATH standard. Since TOTP soft-tokens are easiest to enroll and provision to such a dispersed crowd as kernel developers – and since most kernel developers have access to a smartphone that they carry with them around anyway – TOTP is the preferred mechanism.

In your smartphone's app directory, you should be able to find one of the following applications (links given to Google Play store, but should exist on iOS as well):

• FreeOTP (preferred, free software)
• Google Authenticator (proprietary)
• Authy (proprietary)

The only HOTP devices currently tested and supported are yubikeys. Any of the currently listed products should support HOTP authentication:

• Standard (cheapest)
• Nano (smallest)
• NEO (also works as an OpenPGP card)

We recommend the NEO, as you can also configure it as an OpenPGP card, but laptop users may find that using the Nano is more comfortable.

There is a special "2fa" command in gitolite, used to interact with the 2-factor validation component. To provision, you submit a command via the gitolite interface.

To enroll a TOTP soft-token app, such as FreeOTP or Google Authenticator, run:

ssh git@gitolite.kernel.org 2fa enroll totp

This command outputs the following:

totp enrollment mode selected
New token generated for user mricon

Please make sure "qrencode" is installed.
Run the following commands to display your QR code:
    unset HISTFILE
    qrencode -tANSI -m1 -o- "otpauth://totp/mricon@gitolite.kernel.org?secret=ACHQKMJFHIXJDNRY"
  
If that does not work or if you do not have access to
qrencode or a similar QR encoding tool, then you may
open an INCOGNITO/PRIVATE MODE window in your browser
and paste the following URL:
https://www.google.com/chart?chs=200x200&chld=M|0&cht=qr&chl=otpauth%3A%2F%2Ftotp%2Fmricon%40gitolite.kernel.org%3Fsecret%3DACHQKMJFHIXJDNRY

Scan the resulting QR code with your TOTP app, such as
FreeOTP (recommended), Google Authenticator, Authy, or others.
Please write down/print the following 8-digit scratch tokens.
If you lose your device or temporarily have no access to it, you
will be able to use these tokens for one-time bypass.

Scratch tokens:
19489805
36196876
06341363
70324458
39448548
  
Now run the following command to verify that all went well
    ssh git@gitolite.kernel.org 2fa val [token]

If you need more help, please see the following link:
    https://korg.wiki.kernel.org/userdoc:gitolite_2fa

Please remember to "unset HISTFILE" or your secret will be stored in your ~/.bash_history.

Alternatively, if you absolutely have no other way to locally generate a QR code, it is important to actually open a new "Incognito/Private Mode" window to make sure that the URL containing your 2-factor secret is not saved in your browser history. Note, that if you do use the google link, you'll be giving your 2-factor secret to Google – whatever that implies.

To initialize a yubikey, run the following command instead:

ssh git@example.com 2fa enroll yubikey

The output of the yubikey command is slightly different:

yubikey enrollment mode selected
New token generated for user mricon

Please make sure "ykpersonalize" has been installed.
Insert your yubikey and, as root, run the following command
to provision the secret into slot 1 (use -2 for slot 2):
    unset HISTFILE
    ykpersonalize -1 -ooath-hotp -oappend-cr -a7fd554b1e4a711155d20e9f9615b0451152db3bb
  
Please write down/print the following 8-digit scratch tokens.
If you lose your device or temporarily have no access to it, you
will be able to use these tokens for one-time bypass.
  
Scratch tokens:
88989251
08286736
73163062
90775064
59235228
  
Now run the following command to verify that all went well
    ssh git@gitolite.kernel.org 2fa val [yubkey button press]

If you need more help, please see the following link:
    https://korg.wiki.kernel.org/userdoc:gitolite_2fa

It is important to use "unset HISTFILE" to make sure the secret isn't saved in your ~/.bash_history. Additionally, you may also omit the -a flag and "ykpersonalize" should prompt you for the secret, in which case paste the string that follows the "-a" (but not "-a" itself).

You can test things on the special "testing" repository:

git clone git@gitolite.kernel.org:testing
cd testing
git checkout -b [username]

Edit the README file, commit, and try to push:

git push origin [username]

You should get the following back:

Counting objects: 7, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 308 bytes | 0 bytes/s, done.
Total 3 (delta 1), reused 0 (delta 0)
remote: IP address "x.x.x.x" has not been validated.
remote: FATAL: W VREF/2fa: testing mricon DENIED by VREF/2fa
remote: 2-factor verification failed
remote:
remote: Please get your 2-factor authentication token and run:
remote:     ssh git@gitolite.kernel.org 2fa val [token]
remote:
remote: If you need more help, please see the following link:
remote:     https://korg.wiki.kernel.org/index.php/Userdoc:gitolite_2fa
remote:
remote: error: hook declined to update refs/heads/mricon
To git@gitolite.kernel.org:testing
 ! [remote rejected] mricon -> mricon (hook declined)
error: failed to push some refs to 'git@gitolite.kernel.org:testing'

As instructed, run the following:

$ ssh git@gitolite.kernel.org 2fa val [token]
Valid TOTP token within window size used
Adding IP address x.x.x.x until Wed May 28 20:29:31 2014 UTC
GeoIP information for x.x.x.x: Saint-laurent, Quebec, CA

If you now try the push again, it will succeed:

$ git push origin mricon
Counting objects: 7, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 308 bytes | 0 bytes/s, done.
Total 3 (delta 1), reused 0 (delta 0)
remote: Reading /var/lib/gitolite3/repositories/manifest.js.gz
remote: Updating /testing.git in the manifest
remote: Writing new /var/lib/gitolite3/repositories/manifest.js.gz
To git@gitolite.kernel.org:testing
   307ff91..87b27aa  mricon -> mricon

To list all allowed validations, run:

$ ssh git@gitolite.kernel.org 2fa list-val
{
    "172.x.x.x": {
        "added": "2014-05-27 20:27:44+00:00",
        "expires": "2014-05-28 20:27:44+00:00"
    },
    "24.x.x.x": {
        "geoip": "Saint-laurent, Quebec, CA",
        "added": "2014-05-27 20:29:31+00:00",
        "expires": "2014-05-28 20:29:31+00:00"
    }
}
Listed non-expired entries only. Run "list-val all" to list all.

To invalidate an IP, use the "inval" command, e.g.:

$ ssh git@gitolite.kernel.org 2fa inval 24.x.x.x
Force-expired 24.x.x.x

Instead of the IP address, you may also use "myip" to invalidate the current IP you're connecting from, or "all" to force-expire all active IP validations.

Usually you would need to unenroll only when switching devices. If you still have access to your current device or to the scratch-tokens, you can use them to unprovision your current device by using the "unenroll" command:

$ ssh git@gitolite.kernel.org 2fa unenroll [token]
Valid TOTP token used
Removing the secrets file.
Cleaning up state files.
Expiring all validations.
Force-expired 172.0.0.14.
You have been successfully unenrolled.

You can then use the "enroll" command again in order to provision a new device.

If you do NOT have access to your previous 2-factor device, send a signed email to support and we'll work to re-provision you a new token (once a successfully thorough verification procedure is established and followed).

During this beta-testing period, send mail to support to request that your repository is added to the 2fa list.