copyright statement copyright robert j. brentrup and sean w. smith 2002. this work is the...

Copyright Statement

• Copyright Robert J. Brentrup and Sean W. Smith 2002. This work is the intellectual property of the authors. Permission is granted for this material to be shared for non-commercial, educational purposes, provided that this copyright statement appears on the reproduced materials and notice is given that the copying is by permission of the author. To disseminate otherwise or to republish requires written permission from the author.

Developing and Deploying a PKI for Academia

Robert Brentrup

Sean Smith

Educause Conference October 2002

Dartmouth PKI Lab• R&D to make PKI a practical component of a

campus network• Multi-campus collaboration sponsored by the

Mellon Foundation• Dual objectives:

– Deploy existing PKI technology to improve network applications

– Improve the current state of the art• identify security issues in current products

• develop solutions to the problems.

• Many other institutions are working on PKI.

• Internet2 has been very active in promoting this work establishing PKI Labs at Dartmouth and the University of Wisconsin. – I2 HEPKI-TAG, -PAG, -S/MIME

• Educause Net@EDU and CREN

• 1st Annual PKI Research Workshop– Sean Smith: program chair, proceedings editor

Community

What is PKI?• PKI is Public Key Infrastructure

• A pair of keys is used, one to encrypt, the other to decrypt

Public and Private Keys

• You publish the "public" key, You keep the "private" key a secret

• You don't need to exchange a secret "key" by some other channel

• Invented in 1976 by Whit Diffie and Martin Hellman

• Commercialized by RSA Security

Basic applications of PKI

• Authentication and Authorization of Web users and servers– It is the basis for the SSL protocol used to secure

web connections

• Secure e-mail (signed and encrypted)

• Electronic document signatures

• Network link data protection (VPN, wireless)

• Signing Program Code

Why would I use PKI?

• Effective security has become crucial to extend electronic communication and business processes beyond the current state of the art.

• Legislative mandates are requiring it.

What is X.509?

• A standard for the format of a public key certificate and related standards for how certificates are used.

• Current PKI product offerings inter-operate through this standard

• There are many other possible formulations, eg SDSI/SPKI

• Is X.509 THE solution?

What is a certificate?

• Signed data structure that binds some information to a public key

• The information is usually a personal identity or a server name

• Think of it as an electronic ID card

Basic Public Key Operations• Encryption

– encrypt with public key of recipient

– only the recipient can decrypt with their private key

• Signature – Compute message digest, encrypt with your private key

– Reader decrypts with your public key

– Re-compute the digest and compare the results, Match?

Basic Public Key Operations

What is a certificate authority?

• An organization that creates and publishes certificates

• Verifies the information in the certificate

• Protects general security of the system and it's records

• Allows you to check certificates and decide to use them in business transactions

What is a CA certificate?• A certificate authority generates a key pair

used to sign the certificates it issues

• For multiple institutions to collaborate:– Hierachical structure is setup among their CAs– Bridge Certification Authorities

• "peer to peer" approach

Hierarchy

CREN

Dartmouth Princeton MIT UAB

DST

UC

VeriSign

UWis NIH

???

or Bridge?

CREN

Dartmouth Princeton MIT UAB

DST

HEBCA

UC

VeriSign

UWis

FBCA

NIH

Deployment Results• PKI applications in production use

• develop more and scale up campus wide

• Electronically signed Payroll Applications

• Replace Web authentication• Banner SIS, other Oracle apps, same mechanism

• Library resource access control, local and JSTOR

• Electronic document signatures• NIH pilot, replace paper forms

Deployment issues?• Learning curve for planning a PKI is steep• PKI is as much about Policy as Technology• Commercial products have shortcomings:

– Many are expensive– Some are hard to install and operate– Many compatibility issues and user constraints

• Many applications only interesting if available to the entire "community"

• Many products have serious security issues

External Results• Extensive compatibility testing results published

on websites• Implemented multiple PKI system products,

notes available• Publishing example code derived from new

applications• Notes on PKI libraries and tool kits• Tools and additions to existing applications

– eg. browser mods and S/MIME plugins

Next Steps• Applications

– Workflow, signatures– Secure mail for Student health Services -HIPAA– PKI enhanced List-servers– Wireless network data protection– Databases and E-commerce

• Improvements in Infrastructure– Key storage hardening

• Tokens, smartcards, coprocessors

– Enrollment improvements– Trusted Third Party Services

Research Agenda

• Expression of Trust– PKI system that can be managed and issued by different authorities, but

from which many parties can draw judgments.

• Trust Attributes for Machines– machines throughout network to actually have the right certs...

• Using Trust at Clients– client tools that can reliably recognize and react to these properties…

• Using Trust in Applications– applications to obtain, react, and respond to this information

• Foundations of Trust– techniques to establish a basis for trust in computation in hostile places.

End User Studies• Understanding Incentives and Concerns

• User Concerns, Understanding, Behavior

• Vulnerability Analysis• How easily can users be conned into revealing passphrases?

• Usability of trusted server techniques

• PKI Interface• Dynamics, Usefulness, Reliability

• Perception of Privacy

• Institutional Evolution for Security/Trust

Research Results• User interface of most web applications is insecure• Web browser display can be replaced

• SSL lock icon and the server certificate window!

• Prevent subverted window content• Mozilla mods, synchronized reference window

• SSL is an "Armored pipe to a cardboard box"• Secure Apache web server (WebAlps)

• Documents with active content are not secure• Signed e-mails that display subverted content• Methods for stealing private key

• Trusted Paths for Browsers• USENIX Security 2002

• Prototyping an Armored Data Vault: Rights Management on Big Brother's Computer.

• Privacy-Enhancing Technology 2002

• Digital Signature and Electronic Documents: A Cautionary Tale

• Sixth IFIP Conference on Communications and Multimedia Security

Papers

• Virtual Hierarchies: An Architecture for Building and Maintaining Efficient and Resilient Trust Chains

• NORDSEC 2002

• Web Spoofing Revisited: SSL and Beyond• Outbound Authentication for Programmable

Secure Coprocessors• 7th European Symposium on Research in Computer

Science

Papers

Demo -Digital Signatures

• People frequently take actions on paper documents for personal or official purposes : e.g., signing forms, expense sheets and contracts.

• PKI allows approval and verification of bits.• Can PKI produce and verify electronic documents

so that they work like virtual paper docs?

Virtual Paper?

• Paper documents and electronic documents are different.

• Do the same bits always generate the same virtual piece of paper?

If not then PKI on electronic docs does not work!

When viewed on 09/16/02

When viewed after 09/16/02

Same bits different content

Demos

• JSTOR Access

– Current: http://www.jstor.org/">http://www.jstor.org/

– PKI: https://logon.jstor.org/logon/remote/">https://logon.jstor.org/logon/remote/

• Web Browser Spoofing (IE or Netscape on Win and Linux)

– http://www.cs.dartmouth.edu/~pkilab/demos/spoofing/• Misleading URLs

• E-mail site illusion

• Counter Measures

– http://www.cs.dartmouth.edu/~pkilab/demos/countermeasures/

Contacts

• http://www.dartmouth.edu/~pkilab/

• Mail: sws@cs.dartmouth.edu

• Robert.J.Brentrup@dartmouth.edu