Technical Presentation AIAC 2010-2011 Group 11. System Rationale System Architecture Secure Channel Establishment Username/Password Cartão Cidadão Digital.

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CERTCOP System

Technical Presentation

AIAC 2010-2011 Group 1

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System Rationale System Architecture Secure Channel Establishment

◦ Username/Password◦ Cartão Cidadão◦ Digital Certificate

Secure Functionalities◦ Competence Verification◦ Document Signature and Validation

System Security Analysis

Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Presentation Outline

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Client asked for a system who was able to:◦ Verify a title or competency of a subject;◦ Digitally Sign a document with a given

Competency of a subject.

All the communication and processes performed in a secure fashion

CERTCOP was developed to address these (and more…) requisites

Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

System Rationale

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

System Architecture

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Channel Establishment

3 Modes Used:◦ Username/Password◦ Cartão Cidadão◦ Digital Certificates

Used with a slight modification in Web Server

All modes based on EKE (Encrypted Key Exchange)

At the end each entity has:◦ Public/Private Key;◦ Symmetric Session Key;◦ Mutual Authentication Guarantees.

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Channel Establishment – Username/Password

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Channel Establishment – Cartão Cidadão

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Channel Establishment – Digital Certificate

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Channel – Message Format

One signature is generated for every message

◦ Provides Integrity, Freshness and Non-Repudiation

The original message, along with the Signature, is ciphered with the Symmetric Session Key◦ Providing Confidentiality and Authentication

𝑀𝑒𝑠𝑠𝑎𝑔𝑒𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒(𝑈𝑠𝑒𝑟𝐼𝑑,𝑅𝑒𝑚𝑜𝑡𝑒𝑈𝑠𝑒𝑟𝐼𝑑,𝐶𝑢𝑟𝑟𝑒𝑛𝑡𝑇𝑆,𝑀𝑒𝑠𝑠𝑎𝑔𝑒𝐻𝑎𝑠ℎ,{𝐻𝑎𝑠ℎሺ𝑀𝑒𝑠𝑠𝑎𝑔𝑒𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒)ሽ𝐾−)

𝑆𝑒𝑐𝑢𝑟𝑒𝑀𝑒𝑠𝑠𝑎𝑔𝑒(ሾ𝑂𝑟𝑖𝑔𝑖𝑛𝑎𝑙𝑀𝑒𝑠𝑠𝑎𝑔𝑒,𝑀𝑒𝑠𝑠𝑎𝑔𝑒𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒ሿ𝐾𝑠)

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Functionalities

Competence Verification

Document Signature and Validation

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Functionalities – Competence Verification

𝐺𝑒𝑛𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒(ሼ𝐻𝑎𝑠ℎሺ𝑁𝑜𝑢𝑛𝑐𝑒,𝐶𝑜𝑚𝑝𝑒𝑡𝑒𝑛𝑐𝑦ሻሽ𝐾𝐶𝑖𝑡𝑖𝑧𝑒𝑛𝐶𝑎𝑟𝑑− )

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Functionalities – Document Signature and Validation

𝐴𝑢𝑡ℎ𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒(ሼ𝐻𝑎𝑠ℎሺ𝑁𝑜𝑢𝑛𝑐𝑒,𝐶𝑜𝑚𝑝𝑒𝑡𝑒𝑛𝑐𝑦ሻሽ𝐾𝐶𝑖𝑡𝑖𝑧𝑒𝑛𝐶𝑎𝑟𝑑− )

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Secure Functionalities – Document Signature

To each signed document is generated the following signature:

If the Document has a higher priority it is stored and verified by another system◦ VERICOP

This additional service can be billed at a higher price

𝐷𝑜𝑐𝑢𝑚𝑒𝑛𝑡𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒(𝐻𝑎𝑠ℎሺ𝐷𝑜𝑐𝑢𝑚𝑒𝑛𝑡ሻ,𝑆𝑒𝑟𝑖𝑎𝑙𝑁𝑢𝑚𝑏𝑒𝑟,𝑈𝑠𝑒𝑟𝐼𝑑,𝑈𝑠𝑒𝑟𝐶𝑜𝑚𝑝𝑒𝑡𝑒𝑛𝑐𝑒, 𝑆𝑒𝑟𝑖𝑎𝑙𝑁𝑢𝑚𝑏𝑒𝑟𝑆𝑖𝑔𝑛𝑒𝑟𝐶𝑒𝑟𝑡𝑖𝑓𝑖𝑐𝑎𝑡𝑒 𝑉𝐸𝑅𝐼𝐶𝑂𝑃?,𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒𝑉𝑎𝑙𝑖𝑑𝑖𝑡𝑦,𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒𝐺𝑒𝑛𝑒𝑟𝑎𝑡𝑖𝑜𝑛𝐷𝑎𝑡𝑒, {𝐻𝑎𝑠ℎ(𝐷𝑜𝑐𝑢𝑚𝑒𝑛𝑡𝑆𝑖𝑔𝑛𝑎𝑡𝑢𝑟𝑒)}𝐾𝐶𝐸𝑅𝑇𝐶𝑂𝑃− )

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

System Security Analysis (1/2)

State of the art cryptographic algorithms and protocols used:◦ AES (with 128 bits key and 10 encryption rounds)◦ SHA-2 (256 bits)◦ RSA (with 2048 bits key for certificate, 1024 for

the transient key pairs)◦ Adapted EKE Protocol

Quite few practical attacks reported on those algorithms

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

System Security Analysis (2/2)

System Security is an important issue:◦ Database Servers Isolation◦ Credentials Management◦ Firewall Configuration

Users and Administrators security awareness is vital to the Security◦ Neither Users nor Administrators should ever

release their passwords to anybody

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Departamento de Engenharia Informática (DEI)

AIAC 2010-2011 Group 1

Conclusion

Web Interface will be available in a future release;

System design based on state of the art security technologies◦ Great overall System Security Level

Special care must be taken to the maintenance and operation procedures of the system