CALEA Communications Assistance for Law Enforcement Act


1
CALEACommunications Assistance for Law
Enforcement Act

• Columbia University Dept of Computer Science
• COMS W4995 VoIP Security
• December 3 2008
• John Morales

2
Outline

• History and motivation
• Implication for VoIP
• IETFs Position
• Current Research
• Implication for greater Internet
• Resistance

Clay Bennett Christian Science Monitor
http//www.csmonitor.com/news/cartoonClassics.htm
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3
CALEA History

• U.S. Wiretapping law enacted January 1 1995
• Purpose
• to make clear a telecommunications carriers
  duty to cooperate in the interception of
  communications for Law Enforcement purposes and
  for other purposes.

• Intended audience telecommunication carriers
• Common Carriers (Ma Bell)
• ISPs
• VoIP

4
CALEA Participants

• OK so what does interception mean
• Able to wiretap any conversation for listening
• Save call detail records (dialer receiver
  time duration of call)
• Parties cannot discover when this is happening.
  (Duh.)
• Fine but telecommunication providers is so
  fuzzy!
• First Report and Order (Sept 2005)
• Facilities-based broadband ISPs are covered
• PSTN-interconnected VoIP services are covered
• (Vonage YES Google Chat NO)
• Second Report and Order (May 2006)
• Providers can meet requirements via Trusted Third
  Parties
• Carriers have to foot the bill cannot pass
  surcharge onto customers

5
IETF Weighs In

• RFC 2804 (2000)
• Will wiretapping considerations be included in
  standards
• Nope
• The IETF is the wrong forum for designing
  protocol or equipment features that address needs
  arising from the laws of individual countries
• Comment on moral position
• Nope
• The IETFis not in a position to dictate that
  its product is only used in moral or legal ways.

6
IETF Weighs in (Observations)

• RFC 2804 does highlight some observations
• Copying bytes between two known static internet
  endpoints is a solved problem.

• Associating identities with network endpoints is
  the hard problem.
• (Just ask RIAA/MPAA)
• Easy to circumvent
• Anonymous proxies
• Use public Internet cafes
• Encryption

7
Current Research - Jan Seedorf

• Lawful Interception in P2P-Based VoIP Systems
  (IPTComm 2008)
• SIP difficult to intercept
• Signaling and media take different paths.
• BUT can still be done somethings centralized
• Network provider and VoIP provider could be same.
• If different might have SBC to
• force signaling to central server.
• If no SBC get IP address and
• request ISP snoop in real-time.
• However

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Current Research (Contd) P2PSIP

• Lawful Interception in P2P-Based VoIP Systems

• Wicked stepsister P2PSIP
• No centralized server for call setup.
• No single service provider for intercept.
• P2P Networks are dynamic!
• Cant try to snoop on who has which
  registrations adjusted frequently.
• Cant even know first hop a priori!

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Current Research (Contd) Potential Solutions

• Main problem lack of centralized place to
  intercept signaling
• At least 4 Possible Solutions
• 1.) Put bugs in all devices.
• Access to incoming and outgoing voice at
  endpoints.
• Deals with mobility media monitored at device
  not in network.
• Can ignore network topology (P2PSIP).
• SIP and P2PSIP are open standards softphones
  could have bug stripped out.
• Hardphone firmware could be hacked to strip out
  bug.

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Current Research (Contd) Potential Solutions

• Main problem lack of centralized place to
  intercept signaling
• 2.) Intercept at IP layer
• Stateful Packet Inspection (SPI) to intercept
  all targets traffic
• Feasible if target often uses same ISP.
• Have to know ISP of target a priori to initiate
  LI request.
• All ISPs would need to participate and have SPI
  hardware.
• i.e. Time Money

Image Banksy http//www.dailymail.co.uk/news/art
icle-559547/Graffiti-artist-Banksy-pulls-audacious
-stunt-date--despite-watched-CCTV.html
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Current Research (Contd) Potential Solutions

• Main problem lack of centralized place to
  intercept signaling
• 3.) Follow Hollywoods Example
• Have fake P2P nodes in network watching.
• Good if want to find some traffic.
• Some always better than none.
• Difficult to monitor any traffic to cover all
  nodes must have
• Detailed knowledge of DHT (non-trivial problem)
• Nodes strategically placed for coverage
  (non-trivial problem)

we quantify the probability of a P2P user of
being contacted by such entities and observe
that 100 of our nodes run into entities in these
lists. A. Banerjee M. Faloutsos L. Bhuyan
The P2P war Someone is monitoring your
activities! http//www.cs.ucr.edu/bhuyan/P2P/pape
r206.pdf
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Current Research (Contd) Potential Solutions

• DHTs typically vulnerable to poisoning attacks
  which are mitigated through an enrollment server.
• Server assigns public keys to nodes for
  authentication.
• 4.) Have relationship with enrollment server to
  statically assign node IDs
• Handles mobility nodes statically IDed.
• Still very difficult would require bootstrapping
  the P2P network with specific nodes at specific
  locations coordinated by LEA.

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Greater Impact for the Internet

• Scary CALEA forces integration of network
  layers
• As noted in ITAA report by Steve Bellovin Vinton
  Cerf Whitfield Diffie et al.
• In order to extend authorized interceptionit
  is necessary either to eliminate the flexibility
  that Internet communications allowor else
  introduce serious security risks to domestic VoIP
  implementations. The former would have
  significant negative effects on U.S. ability to
  innovate while the latter is simply dangerous.
• From RFC 2084
• Correlating users identities with their points
  of attachment to the Internet can be
  significantly harder but not impossible if the
  user uses standard means of identification.
  However this means linking into multiple
  Internet subsystemsthis is not trivial.

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CALEA Resistance

• Wiretapping already allowed and easy enough
• Existing U.S. law allows surveillance of internet
  users.
• VoIP just another protocol and application.
• Potential to stifle innovation
• Any new service in the US would have to keep
  CALEA in mind other countries free to invent
  openly.
• Potential to harm internet functionality
• Its the architecture stupid!
• Wont work anyway
• Again monitoring easily bypassed

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Biblio

• http//en.wikipedia.org/wiki/Communications_Assist
  ance_for_Law_Enforcement_Act
• http//en.wikipedia.org/wiki/Lawful_interception
• http//en.wikipedia.org/wiki/Mass_surveillance
• http//en.wikipedia.org/wiki/Secrecy_of_correspond
  ence
• http//en.wikipedia.org/wiki/Call_detail_record
• http//en.wikipedia.org/wiki/Baby_Bells
• http//en.wikipedia.org/wiki/List_of_telephone_ope
  rating_companiesUnited_States
• http//en.wikipedia.org/wiki/ETSI
• http//tools.ietf.org/html/rfc2804
• http//tools.ietf.org/html/rfc3924
• http//www.eff.org/issues/calea
• http//www.fcc.gov/calea/
• http//www.itaa.org/news/docs/CALEAVOIPreport.pdf
• http//i230.photobucket.com/albums/ee151/sjk2udu66
  /Bittorrent.png
• http//blogs.zdnet.com/open-source/images/new20at
  t20logo.jpg
• http//www.yourhtmlsource.com/sitemanagement/media
  /ie404error.png
• http//www.healthcareconsumers.org/images/protest.
  gif
• http//www.dailymail.co.uk/news/article-559547/Gra
  ffiti-artist-Banksy-pulls-audacious-stunt-date--de
  spite-watched-CCTV.html