pwl - Password Locker
pwl is a secure password locker for the command-line.
Installation
pwl is written in Ruby and can be installed using Ruby's gem package manager:
gem install pwl
Basic Usage
Before it can store passwords, pwl needs to initialize the password database. The database file is created with the init
command and located by default at ~/.pwl.pstore
.
pwl init
Storing a password requires a name under which the password can be retrieved later on:
pwl add "Mail Account" s3cret
This command will store the password "s3cret" under the name "Mail Account". Later on this password can be retrieved using the get command:
pwl get "Mail Account"
This command will print "s3cret" to the console (STDOUT).
For more usage information, invoke the help command:
pwl help
Concept
pwl is written in the UNIX tradition of having a tool do one thing, and do it well. With this in mind, password management becomes not much more than keeping a list of name-value pairs and securing it from unauthorized access (by encrypting the password database with a master password).
The whole topic becomes much more interesting when you start integrating a password locker into various tools and applications. There is no widely accepted standard for how password lockers could hook into applications, and so almost every tool falls back to the system clipboard. Notable exceptions are modern browsers, which provide password locker integration by their generic plugin concepts.
pwl focuses on the command line where standard input (STDIN) and output (STDOUT) are the established way to share data between commands (applications). Therefore pwl was built with the following principles in mind:
- All input is read from STDIN
- All regular output (e.g. the password retrieved) goes to STDOUT
- All messages and errors are printed to STDERR (prevents side effects of the message)
- Exit code is set to 0 for success and non-zero for errors
Security
When it comes to securing passwords, pwl does not make any compromises. It relies on the proven OpenSSL library for all encryption functions via the Encryptor wrapper. The password store itself is a Ruby PStore. All names and values are individually encrypted with the master password.
Code security is enforced with two major concepts:
- The complete source code of pwl, and all libraries it uses, are open source. Therefore, everyone can freely inspect the complete source code of pwl, run penetration tests, etc.
- Nearly 100% of pwl's code is covered by unit and acceptance tests. All tests are re-run whenever new code is pushed to the public git repository. All build and test results are published with the help of Travis CI.
Integration
When invoked on a console, pwl will ask for the master password to be typed into the console (using the HighLine library). pwl also behaves well when run in a pipe. You can pipe the master password into pwl. Similarly, instead of printing the retrieved password to the console, pwl's output can be used as input for yet another program.For instance, the popular request for copying a password to the clipboard can be achieved by piping pwl's output into a clipboard application that reads from STDIN, e.g. pbcopy (Mac), xclip (Linux), clip (Windows >= Vista), putclip (cygwin).
Example on MacOS:
pwl get nerab@example.com | pbcopy
Or, if you prefer to enter the master password via a regular dialog box, you can run the same command with the --gui flag:
pwl get nerab@example.com --gui | pbcopy
By calling this line, the password stored under nerab@example.com is copied to the clipboard.
Backup & Restore
- Backup: Copy ~/.pwl.pstore (or whatever you pass in with --file) to a safe place.
- Restore: Replace ~/.pwl.pstore (or whatever you pass in with --file) with the version you kept in a safe place.
Export and Printing
pwl provides a simple export into the HTML format with the following command:
pwl export
This will print raw HTML markup on STDOUT, so it can be written into a file
pwl export > my_passwords.html
and then viewed and printed with a browser. With bcat the export can be directly piped into a browser:
pwl export | bcat
Contributing to pwl
- Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet.
- Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it.
- Fork the project.
- Start a feature/bugfix branch.
- Commit and push until you are happy with your contribution.
- Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.
- Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.
Copyright
Copyright (c) 2012 Nicholas E. Rabenau. See LICENSE.txt for further details.