Biometric Encryption Base RSA Algorithm Supervisor: Ass. Prof. Dr. Dang Tran Khanh Student: Dung Ngo Dinh

CONTENTS  Introduction  Symmetric & Asymmetric Encryption  Biometric and Bio-Crypto System  Biometric Signature using RSA algorithm  Conclusion

Introduction  Systems and their applications require high levels of security  Most of techniques probably in-use today, keys that are generated by algorithms or in random key generators  Merging biometrics with cryptography, we can generate an exclusive key Cryptography provides high and adjustable security levels to access and manage data, resources and services

 Symmetric Encryption  Only a secret key is used  Both sender and recipient know the secret key

 Asymmetric Encryption  Using a key pair  Both sender and recipient know the secret key

Biometric  A biometric is a person’s unique physical or behavioral characteristic  Include fingerprints, hand or palm geometry, retina, and iris and facial characteristics  Biometrics are being used in many applications: physical access control, national ID database to confirm identity, ticketless travel, commuting and maintaining health records, ATM,..etc.

Problems with PKI and Biometrics  The major problem associated with PKI algorithms is management of private keys  The private key is stored in a server or even smart device could be lost or stolen  This key management issue can be resolved by utilizing biometrics for private key access  To enhance security, this require integration of biometrics with some encryption algorithm

Digital Signature using Biometrics  Instead of transmitting the biometric templates over Internet. An unique private key is generated from Cryptograph Algorithm for digital signature  RSA algorithm can be used with 512 byte fingerprint template to generate a private key by finding the closest number which is relatively prime with Euler totient function, Ø(n)

Biometric Signature using RSA algorithm Sender: 1.Generate two prime numbers p and q, 256 bytes each. 2.Let modulus n = p*q and Ø(n) = (p-1)(q-1). 3.Generate decryption key, d from 512 byte iris template by incrementing it to get a closest number relatively prime with Ø(n). Private key = (d,n). 4.Compute encryption exponent, e as the multiplicative inverse of d modulo Ø(n) i.e. e = d -1 mod (Ø(n)) Public Key = (e,n)

Biometric Signature using RSA algorithm 5.Compute message hash H(m) using MD5 or SHA1 where m is the message to be signed digitally. Encrypt H(m) with d and n using the formula : S = (H(m)) d mod n, where S is the signature 6.Encrypt message and signature (m+S), with any previously agreed private key algorithm like DES and send it to the receiver. Note: n, e, hash function to generate H(m) and sender’s identity are made available to receiver in an authenticated manner e.g. using digital certificate

Biometric Signature using RSA algorithm Receiver: 7.Decrypt the message using the previously agreed private key algorithm like DES to retrieve the message and signature: (m+S). 8.Compute H’(m) from message, m. Decrypt signature to retrieve H(m) using: H(m) = S e mod n 9.Compare H(m) with H’(m) and verify the biometric signature (message data integrity and sender identity).

Biometric Signature using RSA algorithm

Conclusion  Biometric Signature has been introduced  It does not replace digital signatures completely but is only used to generate the private key and resolves the key management issue by avoiding storage of private keys anywhere  The generated keys are unique.

Reference  [1] Sayani Chandra, “Generate an Encryption Key by using Biometric Cryptosystems to secure transferring of Data over a Network”. IOSR Journal of Computer Engineering (IOSR-JCE) e-ISSN: , p- ISSN: Volume 12, Issue 1 (May. - Jun. 2013) [2] M Y SIYAL, “A Biometric Based e-security System for Internet-based applications”.

Course work  Building systems with fingerprint authentication by RSA Algorithm