Skip to content


Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
tree: e35d8b18d0
Fetching contributors…

Cannot retrieve contributors at this time

24 lines (21 sloc) 0.97 kb
require 'openssl'
module ActiveSupport
# KeyGenerator is a simple wrapper around OpenSSL's implementation of PBKDF2
# It can be used to derive a number of keys for various purposes from a given secret.
# This lets rails applications have a single secure secret, but avoid reusing that
# key in multiple incompatible contexts.
class KeyGenerator
def initialize(secret, options = {})
@secret = secret
# The default iterations are higher than required for our key derivation uses
# on the off chance someone uses this for password storage
@iterations = options[:iterations] || 2**16
# Returns a derived key suitable for use. The default key_size is chosen
# to be compatible with the default settings of ActiveSupport::MessageVerifier.
# i.e. OpenSSL::Digest::SHA1#block_length
def generate_key(salt, key_size=64)
OpenSSL::PKCS5.pbkdf2_hmac_sha1(@secret, salt, @iterations, key_size)
Jump to Line
Something went wrong with that request. Please try again.