instiki/vendor/rails/activesupport/lib/active_support/message_verifier.rb
Jacques Distler 4e14ccc74d Instiki 0.16.3: Rails 2.3.0
Instiki now runs on the Rails 2.3.0 Candidate Release.
Among other improvements, this means that it now 
automagically selects between WEBrick and Mongrel.

Just run

    ./instiki --daemon
2009-02-04 14:26:08 -06:00

47 lines
1.3 KiB
Ruby

module ActiveSupport
# MessageVerifier makes it easy to generate and verify messages which are signed
# to prevent tampering.
#
# This is useful for cases like remember-me tokens and auto-unsubscribe links where the
# session store isn't suitable or available.
#
# Remember Me:
# cookies[:remember_me] = @verifier.generate([@user.id, 2.weeks.from_now])
#
# In the authentication filter:
#
# id, time = @verifier.verify(cookies[:remember_me])
# if time < Time.now
# self.current_user = User.find(id)
# end
#
class MessageVerifier
class InvalidSignature < StandardError; end
def initialize(secret, digest = 'SHA1')
@secret = secret
@digest = digest
end
def verify(signed_message)
data, digest = signed_message.split("--")
if digest != generate_digest(data)
raise InvalidSignature
else
Marshal.load(ActiveSupport::Base64.decode64(data))
end
end
def generate(value)
data = ActiveSupport::Base64.encode64s(Marshal.dump(value))
"#{data}--#{generate_digest(data)}"
end
private
def generate_digest(data)
require 'openssl' unless defined?(OpenSSL)
OpenSSL::HMAC.hexdigest(OpenSSL::Digest::Digest.new(@digest), @secret, data)
end
end
end