ActiveDirectoryUser.rb

class ActiveDirectoryUser
 require 'restclient'

 @authentication_site = 'https://your_server'
 @find_site           = 'http://your_server'
 @authentication_prefix = '/your_auth_page'
 @find_prefix           = '/cgi-bin/dscl_search.sh?'

 # Returns true if the user has the correct password, false otherwise.
 def self.authenticate(login, password)
   site = RestClient::Resource.new(@authentication_site, :user => login, :password => password)

   begin
     results = site[@authentication_prefix].get
     auth_succeeded = true
   rescue
     auth_succeeded = false
   end

   auth_succeeded
 end

 # Returns the dscl information of the user if they exist, nil otherwise
 def self.find(login)
   begin
     dscl_results = RestClient.get("#{@find_site}#{@find_prefix}#{login}").to_s
     if dscl_results.blank?
       dscl_results = nil
     end
   rescue
     dscl_results = nil
   end

   dscl_results
 end
end

dscl_search.sh

#!/bin/bash

echo "Content-type: text/plain"
echo
dscl localhost -read /Search/Users/${1}