pstore :: Python Protected Password Store

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Quick jump: Summary | Usage examples | Installation_ | FAQ_

Do you want to store and share passwords? With pstore you store the encrypted passwords on a remote server. All encryption is done locally by the command line interface, so the server never sees your unencrypted passwords.

Summary

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pstore allows you to store and retrieve passwords and other sensitive data in a safe manner. The permission system allows you to share these secrets with others on the same pstore server.

For passwords and other secret items, you encrypt them on the client side automatically with the pstore client. This way the pstore server never has any knowledge of the secret content, and your data is secure (*) even when the server is breached.

Encryption is done using GPG. One of the admins installs your public key on the pstore server. After that you're ready to go.

(*) Security of course depends on everyone using strong secret keys and everyone keeping them private.

Usage examples

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You have set your .pstorerc:

::

$ cat ~/.pstorerc 
--store-url=https://my.pstore.server/

List all machines that contain example in the name:

::

$ pstore example
  Machine                   User access
------------------------------------------------------------------------
+ new.example.com           joe, walter
+ walter.example.com        walter

List machine password for walter.example.com:

::

$ pstore walter.example.com
ip-address = 1.2.3.4
password = wAlTeR!

Add a new machine password, also accessible for joe:

::

$ pstore -c walter2.example.com +joe
Type new machine password: 
Type new machine password again: 

$ pstore example
  Machine                   User access
------------------------------------------------------------------------
+ new.example.com           joe, walter
+ walter.example.com        walter
+ walter2.example.com       joe, walter

$ pstore walter2.example.com
password = abc

Add a public (unencrypted) and shared (encrypted) property to the new machine:

::

$ printf walter2 | pstore walter2.example.com -ps ssh-username
$ cat ssl-cert.key | pstore walter2.example.com -pe ssl-cert.key
$ pstore walter2.example.com
ssh-username = walter2
ssl-cert.key = (1533 byte encrypted)
password = abc

See the contrib directory for bash completion scripts and a dirty hack to supply the password to the ssh client automatically.

Installation

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Installing the pstore client is a matter of running pip install ./pstore-<version>.tar.gz. This will install the necessary requirements and install the pstore binary in your path.

Installing the pstore server is a little bit more work:

1. Install pstore, the client (see above).

2. Refer to the Django project for detailed django installation procedures. But it should basically be something like this:

   • Make a virtualenv (optional).
   • Install the requirements from requirements.txt (optional, the django-pstore installation does this too).
   • Install django-pstore.
   • Copy pstore/settings.py.template to pstore/settings.py and configure as needed. Those comfortable with Django, can choose to integrate it into a different project. Don't forget to set the DATABASES and SECRET_KEY variables.
   • Make known where your settings are, by exporting the DJANGO_SETTINGS_PATH and/or DJANGO_SETTINGS_MODULE environment variables with the right values.

3. Run django-admin.py syncdb. It will create the necessary tables and an admin account for you.

4. Check and alter pstore/wsgi.py as needed.

5. You can now run the development server to test: django-admin.py runserver. When you're done testing you should set it up on a proper webserver (nginx+uwsgi, apache+mod_wsgi or whatever floats your boat). Don't forget to tell the wsgi server your virtualenv path if you're using that.

Set up users and keys:

1. If you used the supplied pstore/settings.py you'll surf to localhost:8000 (or where the site is running). Supply your admin credentials.

2. Go to Auth -> Users. Add users as appropriate.

3. Go to Pstore -> Public keys. Add a single public key for every user that should be using the system. A GPG public key can be extracted from your keyring using gpg --export --armor [email protected]. The key value should look something like this. The description is for human consumption only.

   ::

   -----BEGIN PGP PUBLIC KEY BLOCK-----
   Version: GnuPG v1.4.11 (GNU/Linux)
   |
   mI0EULkssgEEAKeoPrMO5CHxoO8/KTXLA1FP2IQr4n3Og+DvsziIZ6vdcDmhtcsx
   ...
   AK968N1Yrw+ytDuus3s7xPXYAw==
   =TEm/
   -----END PGP PUBLIC KEY BLOCK-----
   

   If you have good reasons, you can go old style and use the SSH public key here, like this:

   ::

   ssh-rsa AAAAq2qMaC2...fBPcPsqMcwqsMHnBCzA= [email protected]
   

   Using GPG is preferred however.

Set up the client:

1. You'll install the pstore client package on all machines that you'll want to connect from.
2. Set up ~/.pstorerc. You can put anything in there that you see in pstore --help, but generally you'll want one or more --store-url= items in there. And possibly a --user=.
3. Type pstore -c my.first.machine to create a password for my.first.machine.

You're ready to go. Call the pstore client with --help and --help --verbose for more help and tips.

FAQ

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How do I install a downloaded tgz?

::

    sudo pip install ./pstore-<version>.tar.gz
    sudo pip install ./django-pstore-<version>.tar.gz

For the client you'll only need the first package.

configure: error: no acceptable C compiler found in $PATH

.. or various other compile related errors when running pip install.

Make sure you have a C compiler (gcc) and python development headers.

::

sudo apt-get install build-essential
sudo apt-get install python-dev

Or you could install the dependencies manually.

::

# for the client and server
sudo apt-get install python-gpgme python-pyasn1 python-crypto
# for the server
sudo apt-get install python-django python-mysqldb

fatal error: gpgme.h: No such file or directory

pygpgme requires the libgpgme development headers.

::

    sudo apt-get install libgpgme11-dev

Couldn't find index page for 'pstore' (maybe misspelled?)

Make sure you install the pstore package before installing django-pstore. This shouldn't be necessary anymore, as we've uploaded that package to PyPI.

How do I uninstall?

Uninstalling the client package is done using *pip*:

::

    sudo pip uninstall pstore

You may need to ``rm /usr/local/bin/pstore`` manually.

For the server, you'll probably need to do more than just uninstalling
``django-pstore``. After all, you put the app in a Django project and
you created a database for it.

Note that dependencies like Django, pyasn1, pycrypto, pygpgme, aren't
uninstalled automatically.

ImportError: No module named pstorelib.bytes

When running ./bin/pstore when developing, you'll need to tell it where the packages are:

::

export PYTHONPATH=`pwd`

NOTICE: re-using cached password

To make the application usable, decryption passphrase information has to
be cached. Preferably, this is done using some kind of password agent
like *gpg-agent*. If such an agent is unavailable, we cache the password
in cleartext in memory for the duration of the pstore command.

The NOTICE is there to remind you that it is not as safe as it could be.

How do I make password caching agents forget my password?

Your graphical desktop environment generally starts a password caching daemon. That could be seahorse-agent or gpg-agent or something else.

I couldn't find a way to reliably clear the seahorse-agent password cache. I only found reliable ways to kill it by accident (on Ubuntu 10.04).

The gpg-agent (gnupg-agent package) seemed more stable. (Log out and in after install.) Making it forget your cached passphrase is a matter of sending it a SIGHUP.

::

pkill -HUP gpg-agent

(If you're now wondering, like me, who then caches your decrypted private ssh key: it's the ssh-agent, even though it's the gnome-keyring who asked for the password. Clearing the ssh-agent cache is a matter of doing ssh-add -D.)

crypto error: encrypt message too long

You're probably trying to set a larger property on an object where an
sshrsa user has permissions. Either convert all users to use GPG or
upload the large property as public (unencrypted!) property.

Issues with large file support
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

When running the integration test, you could see something like this:

::

    * Large file support (adding large public file):
    backend error: could not connect to http://127.0.0.1:8000

      FAIL: could not write large unencrypted file
      > NOTICE: not encrypting the value

This is likely caused by apparmor(1) on the mysqld. We need read/write
permissions in /tmp.

Further, you may need to increase the ``max_allowed_packet`` to
something higher than ``16MB`` if you want to store larger files.

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