Obfuscate

A simple way to obfuscate ids and text. Useful when you have to make ids visible to users. Integrates directly with Rails 3.

The goal is to make simple obfuscated ids that are not huge. This is achieved by using an implementation of Blowfish and encrypting a single block. This produces a nice id of 11 characters (11 since the trailing = is removed by default), for example 3NINgAbOhPc. The caveat is, the id must be within 99,999,999, e.g. a max length of 8.

Text can be obfuscated using Blowfish's string encryption as well, but than it produces output that is larger than the elegant 11 character from single block encryption.

https://github.com/mguymon/obfuscate

RDoc

Install

gem install obfuscate

Ruby Usage

A simple example

Obfuscate.setup do |config|
  config.salt = "A weak salt ..." # Length must be between 1-56 
  config.mode = :string           # defaults to :string
end

obfuscated = Obfuscate.obfuscate( "test" )   # "HoDruKtafqyLxZxu9s-kYQ=="
clarified = Obfuscate.clarify( obfuscated )  # "test"

Rails Integration

Create an initializer in config/initializers with:

require 'obfuscate/obfuscatable'
Obfuscate.setup do |config|
  config.salt = "A weak salt ..." # Length must be between 1-56 
end

Now add to models that you want to be Obfuscatable, with possible config options:

class Message < ActiveRecord::Base
  obfuscatable # a hash of config options can be passed.
end

To get the 11 character obfuscated_id, which uses mode :block for the Blowfish single block encryption:

message = Message.find(1)
obfuscated = message.obfuscated_id           # "NuwhZTtHnko"
clarified = message.clarify_id( obfuscated ) # "1"

Message.find_obfuscated( obfuscated )        # raises an ActiveRecord::RecordNotFound if the found record does not exist
Message.find_by_obfuscated_id( obfuscated )  # returns nil if the found record does not exist

Or obfuscate a block of text, defaults to mode :string which uses Blowfish string encryption, allowing longer blocks of text to be obfuscated.

obfuscated = message.obfuscate( "if you use your imagination, this is a long block of text" ) # "GoxjVCCuBQgaLvttm7mXNEN9U6A_xxBjM3CYWBrsWs640PVXmkuypo7S8rBHEv_z1jP3hhFqQzlI9L1s2DTQ6FYZwfop-xlA"
clarified = message.clarify( obfuscated )

Benchmarks

Some benchmarks from my dev machine, with cpu clocking in at 2.53ghz:

Obfuscate.setup :salt => 'a very weak salt indead.'

puts Benchmark.bm { |bm|
  ids = []
  bm.report("obfuscate x1000:") { 
    1000.times { ids << Obfuscate.obfuscate( rand(1...99999999), {:mode => :block} ) }
  }

  bm.report("clarify x1000:") {
    ids.each { |id| Obfuscate.clarify( id, {:mode => :block} ) } 
  }
}

user     system      total        real
obfuscate x1000: 27.110000   0.000000  27.110000 ( 27.145539)
clarify x1000: 27.270000   0.000000  27.270000 ( 27.304084)

License

Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

obfuscate