arver

  • https://git.codecoop.org/projects/arver

DESCRIPTION:

arver is a tool to manage encrypted harddisks.

Imagine you are a collective with several admin members. Your servers have diffrent LUKS encrypted devices.

Either you would need 1 password for every device which everyone needs to know or you use arver! Arver has 1 password for each device and for each member. This password is stored encrypted with the personal gpg-key in the data directory. The admins only need to know the password to the their own gpg secret key.

This has the following advantages:

  • No need to share passwords or password patterns
    • Often people share passwords amongst each another. This has the drawback that in case of an emergency every password needs to be changed. Which means that everyone else needs to learn a bunch of new passwords and changing these passwords is also quite cumbersome and time consuming.
    • As the amount of passwords might grow with your disks and hosts you will start using a password pattern to derive passwords for each disk from that pattern. This has the drawback that you can hardly share only partial access to disks with a certain admin, as if she knows the pattern she will also likely have access to every other disk. Furthermore, if once one password is leaked and the patter is easily visible, all the other passwords are also compromised.
  • Managing your encrypted harddisks is scriptable, which means that you can recover much faster from outages
  • Revoking access for an admin is scriptable and therefore done in one call and also much safer than revoking manually for each disk.
  • Finer grained access. As for each user and each disk there will be a seperate password by design. You can also grant access to certain disks also only selectively. So for example new admins in your group can only open the disks for your most important services or for which they are respnsible, while access to the other disks is restriced to other admins.

Usage

arver ships with a detailed man page, describing the usage in detail.

Limitations

  • arver supports only up to 8 users as LUKS has only 8 key slots (LUKS NUMKEYS).

Known Issues

GPGME and gpg-agent

If arver asks you multiple times for the password, you might consider to use gpg-agent, so you can decrypt your keypair once and the use it for all your stored keys.

You can test gpg-agent by trying to decrypt an encrypted file for your user in data/keys/USERNAME/key_X . It will tell you about possible gpg-erorrs.

Configuring gpg-agent is quite simple and you find information on the following website: http://dougbarton.us/PGP/gpg-agent.html

If you install gpg-agent like dougbarton recomends, you need to further verify that the environment variable GPG_AGENT_INFO is accessible within the arver script. An option is to add the following entry to your .bashrc

if [ -r “$HOME/.gpg-agent-info” ]; then . $HOME/.gpg-agent-info export GPG_AGENT_INFO fi

Requirements

arver only works with cryptsetup-luks >= 1.0.5 as previous versions do not support key slots properly for our usage.

Installation

The easiest way to install arver is by gem

sudo gem install arver

This will install all required dependecies automatically. If your distributions contains an arver package we recommend installation by your package manager.

The following ruby gems are required for arver:

  • gpgme 2
  • activesupport 2
  • escape

For development you will need the following additional gems:

  • rake
  • cucumber
  • rspec

License

(The MIT License)

Copyright © 2010 arver

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the ‘Software’), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.