Prevention of Man-In-The-Middle Attack in Diffie-Hellman Key Exchange Algorithm using Proposed Hash Function

The key exchange process is a very important feature for many parts in cryptography. In data encryption, symmetric encryption techniques need to share the same secret key securely between two parties before encryption and this is a challenging task for secure data transmission. Most symmetric key encryptions and key management systems widely use Diffie-Hellman Key Exchange (DHKE) algorithm for the purpose of key distribution because it has simple computation and supports forward security. However, there is no key authentication and Man-In-The-Middle (MITM) attack has occurred during the key generation process. To overcome this problem, a new hash function is proposed to get the public key integrity during the public key sharing process of DHKE algorithm. This hash function is created by using six bitwise operators and operated in a variable length of the rounds depending on message length. Thus, the proposed system improves the security of DHKE and grantees the user authentication requirements