From: Pelle Braendgaard <pelleb@...>
Date: 2005-10-31T16:04:51+09:00
Subject: [ANN] EzCrypto 0.2 with Rails support

I have no added released EzCrypto 0.2, where the big news isActiveCrypto which adds crypto support to Rails applications. The ideawas to add cryptography via a single line or two of code in youractiverecord model and another line or two in a controller somewhere.
Features
* Transparent encryption/decryption* Ruby on Rails like domain language
Simple examples
A SIMPLE ENCRYPTED CLASS
You specify in your class which fields are encrypted:
	class Document < ActiveRecord::Base		encrypt :title,:body	end
Two encrypt it you need to enter a key. For ease of use there is amethod called enter_password which sets the key based on a password ofyour choice.
	doc=Document.new	doc.enter_password "This stuff is secret man!!!"	doc.title="Plan to take over the world"	doc.body="Write apps in Rails"	doc.save	This needs to be done as well if you want to read your document:
	doc=Document.find 1	doc.enter_password "This stuff is secret man!!!"	puts doc.name	If you don't remember to set a key it will through a MissingKeyError.
MORE REALISTIC EXAMPLE WITH KEYHOLDER
It probably isn't much use if each record needs its own key. Thesolution to this is the KeyHolder. A KeyHolder is an object that holdskeys for use by other objects. A typical example would be a user.
	class User < ActiveRecord::Base		has_many :documents		keyholder	end
We use standard ActiveRecord associations to associate the User withhis documents. We also need to specify that he is a keyholder. We nowmodify our Document class as follows:
	class Document < ActiveRecord::Base		belongs_to :user		encrypt :title,:body,:key=>:user	end
We have the standard associations going on here, but we have alsoadded the option :key=>:user to the encrypt statement. Now we could dothis:
	@user=User.new	@user.enter_password "This stuff is secret man!!!"	@user.save		@doc=Document.new	@doc.user=@user	@doc.title="Plan to take over the world"	@doc.body="Write apps in Rails"	@doc.save	You could also do ordinary rails like stuf such as:
	@user.documents.each do |doc|		puts doc.name	end
Decryption is done transparently.
When doing this within a rails application, active_cryptoautomatically maintains a list of keys for each user session. Besidesthe 2 steps below you don't need to do anything special within yourcontroller.
1. When a user logs on with a password enter his password like this:
	@user.enter_password @params['password']
2. When a user logs off call the following
	clear_session_keys	I welcome feedback. As mentioned I am doing  some for me some hairyruby programming linking it into Rails. I would like to hearsuggestions from some of the actual Rails frameworks maintainers andothers about what could be done to improve it and integrate it evenbetter into rails.
See my blog where I talk a bit about current and future usage patterns:
http://neubia.com/archives/000402.html
Cheers
Pelle--https://stakeitout.com + Stake out your own micro ventureshttp://stakeventures.com + Bootstrapping bloghttp://neubia.com      +  Geek bloghttp://SoapBX.com    + Get on the box and shout