Transcript Two
The Aerospace Clinic 2002 Team Members Nick Hertl (Project Manager) Will Berriel Richard Fujiyama Chip Bradford Faculty Advisor Professor Michael Erlinger Aerospace Liaisons Joseph Betser, PhD Rayford Sims Overview • Background Information • Tunnel • Technical Approach – Completed work – Tunnel Demo – Future work • Questions Background • • • • • TCP/IP Network Security Firewalls BEEP IDXP TCP/IP • Main protocols used over the Internet • Provides reliable, full-duplex, peer-topeer communication • Most current application protocols use this directly: HTTP (web), SMTP (email), etc. • Multiple connections to the same machine are handled using ports Today’s Internet Network Security • Only authorized users should be able to access private networks • Some data and services should only be available internally • Firewalls are used in most corporations to restrict access to network resources Firewalls • Set of rules to restrict network traffic • Can filter by any combination of: – Source IP – Destination IP – Port – Protocol • Rule sets are usually static Today’s Internet with Firewalls BEEP • Blocks Extensible Exchange Protocol • General framework for the rapid creation of application-level protocols • Provides a message framing mechanism and many common services (profiles) • Application chooses services (e.g. security) or protocol (HTTP, IDXP) • Requires an underlying transport protocol – TCP Tomorrow’s Internet with BEEP IDXP • Intrusion Detection eXchange Protocol • Standard communication of Intrusion Detection messages (IDMEF) • BEEP profile • Firewall must not block authorized messages The Internet with Tunnel Tunnel • Our focus is Tunnel for IDXP messages Tunnel • Uses XML messages to establish a tunnel: <tunnel fqdn=“host1.example.com" port="10289"> <tunnel /> </tunnel> • Parsed at every host. Tunnel • Characteristics – Poke a “controlled” hole in firewall – short lived – Mutual authentication of client/server – Application level security • Differs from – SSH which has one sided authentication – VPNs which are long lived – IPSec which requires OS modification Problem Statement • Evaluate and implement the Tunnel specification as a BEEP profile in at least two programming languages. Deliverables • Evaluation of Tunnel specification – Will this work? – What needs more clarification? • Tunnel Implementation in C and Java – Fully documented code tree for both languages – Sample Client/Server/Proxy Applications Completed Work • Evaluated Tunnel Specification • Chose BEEP Implementations • Implemented – Host to Host Tunnel – Single Firewall Tunnel • Some interoperability testing Fall Schedule Tunnel Evaluation • No standard way to extend the DTD. • Previously no IPv6 support in the DTD. • Possibility for loops with misconfigured servers. • No way to specify a Time-To-Live when using a dynamic route, ie: connecting to a service rather than a host. BEEP Implementations: • JAVA: – PermaBEEP 0.8 (Better API) – Beepcore–java 0.9.07 (TLS support) • C – Roadrunner 0.9 (More fully implemented) – Beepcore–C 0.2 (Abandoned) Host to Host Tunnel • Profile and application can successfully open a tunnel to a host with no firewall in between. Single Firewall Tunnel Tunnel host1.example.com proxy.example.com Transport Connect TCP host2.example.com Tunnel host1.example.com proxy.example.com host2.example.com Transport Connect BEEP Greeting Advertise services (Tunnel, maybe others) Tunnel host1.example.com proxy.example.com host2.example.com Transport Connect BEEP Greeting Start Tunnel <tunnel fqdn="host2.example.com" port="10288"> <tunnel /> </tunnel> Tunnel host1.example.com host2.example.com proxy.example.com Transport Connect BEEP Greeting Start Tunnel Transport Connect TCP Tunnel host1.example.com host2.example.com proxy.example.com Transport Connect BEEP Greeting Start Tunnel Transport Connect BEEP Greeting Advertise services (Tunnel, maybe others) Tunnel host1.example.com host2.example.com proxy.example.com Transport Connect BEEP Greeting Start Tunnel Transport Connect BEEP Greeting Start Tunnel <tunnel /> Tunnel host1.example.com host2.example.com proxy.example.com Transport Connect BEEP Greeting Start Tunnel Transport Connect BEEP Greeting Start Tunnel OK <ok /> Tunnel host1.example.com host2.example.com proxy.example.com Transport Connect BEEP Greeting Start Tunnel Transport Connect BEEP Greeting Start Tunnel OK OK <ok /> proxy now transparently forwards messages Tunnel host1.example.com host2.example.com proxy.example.com Transport Connect BEEP Greeting Start Tunnel Transport Connect BEEP Greeting Start Tunnel OK OK BEEP Greeting Advertise services (proxy now invisible) Future Work • Firewall daemon (Enforce Security Policy) • Multi-Firewall Support • More interoperability testing between C and Java implementations. • Bug squashing • Final report Spring Schedule Questions?