Research And Implementation Of Network Filter Driver Base On PPPoE Protocol For Mac OS X System

With the spread of the internet technology, the service of broadband become sopopular. Now the one of the most popular Broadband Access Technologies isPPPoE(Point to Point Protocol over Ethernet) base on ADSL(Asymmetric DigitalSubscriber Line). For Apple Inc.the occupancy rate of product marking become moreand more high, requirement of the product based on apple system also becomeso.How to realize the Broadband Access on the apple system? Although the Appplesystem has the function of PPPoE in nature.The difficulty of the conmunication withPPPoE and Radius(Remote Authentication Dial in User Service) is that,authenticationmethod CHAP(Challenge Handshake Authentication Protocol)/PAP (PasswordAuthentication Protocol)of standard PPPoE is stateless for Radius,can not protect theuser data.The content of this study is how to implement safe PPPoE dial-up and protect theauthentication information on Apple system.In this paper, achieve authentication datapackets secondary encryption through the filter driver. Effectively protect the userdata by a secondary interaction with Radius and prevent the packet re-injection.Evenif the packet is intercepted by the other program is not able to complete theAuthentication.To complete the authentication must use the driver to interact withRadius and use the encryption algorithm.This paper studies the principle of PPPoE protocol. Mainly including PPPprotocol, PPPoE protocol packet format, PPP protocol link establishment process andPAP, CHAP authentication method. Depth study of the Mac OS X system frameworkkernel module network mechanisms and MD5encryption.Proposes a program thatencryption protection the PPPoE dial-certified under Mac OS X system.Implement abased ethernet network filter driver could secondary encryption the PPPoEauthentication packets.As well as, in the certification process conducted a number of interaction with the Radius server to negotiate an encryption algorithm and encryptionto protect the data packets.The experiments show that filter driver can be betterprotectd by encryption for authentication packets and pass the server’sauthentication.The authentication packets send through third party dialer can not beissued because these packets without driver encryption.