Formal Methods Demo Session Initiation Protocol (SIP) Vulnerability Testing

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Formal Methods DemoSession Initiation Protocol
(SIP)Vulnerability Testing
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SIP Network in SDL
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Call Hijacking Possible Scenario
SIP Proxy Registrar
1006
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Dial 1006
LAN
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Dial 1006
1007
1004
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Re-Registered
Covert Registrar/Proxy Routes the Call
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Vulnerability to Call Hijacking
Vulnerable - Phone accepts the Registrar without
authentication
Corrected - Phone rejects unauthenticated
Registrar
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Vulnerable
Cisco IP Phone 7940
REGISTER requests stop
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Corrected
The SDL Model of the IP Phone authenticates the
proxy
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Formal Approach in Design and Testing

• Formal Languages and Methods (SDL, MSC, ASN.1,
  TTCN)
• every statement is mathematically provable to be
  correct
• every statement validated by trusted tools
• standards and spacifications can be validated
  before approval
• Programming code generated by machine
• no human intervention
• no errors, no Trojan horses
• Trusted tools generate the implementation
• tools based on formal techniques can be certified
  as trusted
• implementation of a standard can be certified as
  trusted
• Tests generated from validated specifications
• traceability to trusted design requirements and
  specifications