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Rserpool Security. Maureen Stillman July 14, 2003 maureen.stillman@nokia.com. Design Team objectives. Revisit i-d draft-ietf-rserpool-threats-00.txt Add directives from Transport Area Directors Secure Rserpool infrastructure does not include application (PU-PE data)
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Rserpool Security Maureen Stillman July 14, 2003 maureen.stillman@nokia.com
Design Team objectives • Revisit i-d draft-ietf-rserpool-threats-00.txt • Add directives from Transport Area Directors • Secure Rserpool infrastructure • does not include application (PU-PE data) • Support client (PU) to ENRP server authentication • PU authenticates ENRP server to prevent rogue ENRP servers
PE and ENRP security • Mandatory to implement TLS OR IPsec security • Choice is design decision left to the designers and network architects • Open issue • Since the last IETF design team has only talked about TLS – do we want to mandate this only and not discuss IPsec? • Using IPsec • Must implement draft-ietf-ipsec-sctp-04 • Using TLS • MUST support TLS with SCTP as described in RFC 3436 or TLS over TCP as described in RFC 2246
PU Authenticates ENRP server • Consensus reached by the security design team • TLS would be used by the PU to authenticate the ENRP server (mandatory to implement) • Other methods of authentication are optional • TLS was deemed mandatory to implement for reasons of interoperability
Threats to consider • What are the threats? • Rouge ENRP servers • Rouge registrations from PEs or unauthorized PEs • PE thinks it has registered with a “good” ENRP server, but it is really a rouge • Corrupted data • Sent from the ENRP server to the PU • Sent from the PE to the ENRP server • PU-PE authentication addresses only #1
Issues • What I really want to know is that the addresses served up to the PU are “trusted” • Want to know that all the PEs have registered with a “trusted” ENRP server • Therefore, the real threat is the one of bogus addresses for PEs or no addresses for the PEs • Do we need data integrity as well? (yes) • What about a “mixed” ENRP database – some entries trusted, some not
Security Architecture PU PU authentication, integrity authentication, integrity Mutual authentication, integrity ENRP Server PE PE Mutual authentication, integrity
ENRP mixed security database PE A pool “foo” ENRP PE B pool “foo” PE C pool “foo” PE D pool “foo” ENRP foo Database PE A,C – secure PE B, D – not secure
Mixed data base issues • Need to mark PE registrations – some have used security to register others not • When a PU requests a list, does it get the mixed list or one or the other? • Makes implementation more complex • Conclusion – mixed database not allowed; either all secure or all not secured
TLS ports – 1 port or 2 ports?2 port solution IANA assigns two ports for ENRP PE ENRP PE Register with ENRP using TLS
TLS ports – 1 port or 2 ports?1 port solution IANA assigns one port only PE ENRP PE First send unsecured message with upgrade to TLS request; MITM can refuse upgrade; Fix: Protocol change to ASAP to request upgrade; can’t be rejected by ENRP
Advice received • We have gotten advice from Jon Peterson and Eric Rescorla • Both endorse the 2 port and one port solutions • We have asked IANA for two ports
Open issue – control channel • Two options • Data channel only • Control and data -- We have decided to multiplex the data and control channel • When the data channel is secured, the control channel is as well due to the mux • If data is not secured, neither is the control • Is this solution OK?
Next steps • Are we there yet? • Are there other open issues? • Join the security design team to help • E-mail maureen.stillman@nokia.com