An approach to achieve message integrity using SHA-256 and Elliptic Curve Cryptography with Salting

Abstract

In this digital world, securing the integrity of the information plays an important role. For a modernized venture, information integrity is requisite for the veracity & competence of employment processes and decision-making. Integrity verification is the one where the information has not been tampered with while it is stored or communicated. Hash function such as SHA-256 is the strongest function, can be used to achieve information integrity. In this paper, a method is proposed where the images are hashed using SHA-256, scrambled using Elliptic Curve Cryptography (ECC), and then added the salted values to generate the secret image. ECC helps achieve high security with a smaller key size. Salting is applied to the scrambled image to increase the randomness. This makes it difficult for the attacker to identify the secret image and reverse back the hashing as hashing is a one-way function. Simulation outcomes of the proposed method have been analyzed by measuring Peak Signal to Noise Ratio (PSNR), Mean Squared Error (MSE), Structural Similarity Index (SSIM), Number of Pixel Change Rate (NPCR), and Unified Average Changing Intensity (UACI). The proposed method is strong against the differential attacks.