1 st International Conference on Islamic Applications in Computer Science and Technologies, 1 st -2 nd July, 2013 Protection of the digital Holy Quran Using SAB hash function Mohammad A. Ahmad 1,a , Dr. Imad Fakhri Alshaikhli 1,b , 1 Department of Computer Science, International Islamic University of Malaysia, 53100 Jalan Gombak Kuala Lumpur, Malaysia, a malahmads@yahoo.com, b imadf@iium.edu.my Abstract Cryptography consists of a set of algorithms and techniques to convert the data into another form so that the contents are unreadable and unexplainable to anyone who does not have the authority to read or write on these data. One of the tools used by cryptography is the hash function. The hash function is used to hash the file so that if anyone tries to modify the text in the file, the number of file obtained from hashing will change. In this paper, we designed a concrete hash function called SAB. SAB hash function uses a permutation Q used in Grøstl hash function as a permutation function. Also, it uses the fast wide pipe (FWP) construction designed by Nandi and Paul presented in Indocrypt2010 conference. SAB hash function is designed to protect the data integrity of the digital Holy Quran from alterations or manipulations. SAB hash function outputs 512-bits as the final digests. Keywords: FWP, permutation, Digital Holy Quran, SAB hash function 1.Introduction Allah sent down his book, the Quran, to be the dominant book, the final message, and the law. The Prophet, peace be upon him, had some people write down his revelations, and reviewed it himself, so rest assured regarding the accuracy of what was written. It was the Messenger of Allah, peace be upon him, who forbade writing other than the Quran, such as hadith and interpretations of the Quran. After the death of the Prophet, peace be upon him, a book of Allah and the conservation and care of the religion was manifested through two great incidents, as follows: First, in the era of the first caliph Abu Bakr, may Allah be pleased with him, while many of the keepers of the Quran died in war, he and a group of senior companions feared that the Quran would be lost. So he ordered the collection of the Quran, by gathering all that was written on wood and leather, as well as what was preserved in the hearts of men. The Quran was collected in one place, supervised by the caliph and his successors after him. Second, in the era of the third Caliph Othman bin Affan, may Allah be pleased with him, when language differences the led to conflict between Muslims, the Caliph standardized the Muslims on one language, the language of Quraish or Arab tribes, and several copies of the Quran circulated throughout various regions and cities (wikisource, 2009). The method used to copy the Holy Quran and distribute the copies among the regions was by handwriting. Even with the development of civilization, the progress of the State, and the evolution of technology, handwriting is still the method used in copying and dissemination of the Quran. After writing out the Quran, it is entered into the computers in the form of a scanned image. It can then be printed after auditing by specialists in this area; in recent times, the holy Quran has been printed electronically using the computer, which made the book subject to change and substitution. We need to protect the holy Quran from such alterations. There are several hash functions can protect the information and files from alterations. This paper discusses the design of a concrete hash function called SAB. SAB hash function uses a permutation Q used in Grøstl hash function [1] as a permutation function. Also, it uses the fast wide pipe (FWP) [2] construction