Investigating the optimal algorithms of robust cryptography for implementation on FPGA

Dissertation for Master's Degree (M.Sc)

Electrical Engineering - Electronics Orientation

Abstract

Shash function is a type of abstracting function that is used in all encryption designs and security protocols to generate random numbers and password storage mechanism for authentication and digital signature in the digital world.

National Institute of Standards and Technology, He started a competition to improve common abstract generator algorithms. The abstract generator algorithms sent to this competition were named SHA-3, including 5 resistant algorithms that were able to reach the final round of the competition. On the other hand, the JH algorithm was introduced as the second algorithm of the competition in the final round. Therefore, the purpose of this thesis was to investigate the JH abstract generator algorithm in order to implement it on FPGA. In this algorithm, the observations obtained do not include false sources. These simulations show to what extent the performance of the JH abstract generator algorithm has been able to be simulated and synthesized on FPGA.

Keywords: encryption, abstract generator function, Cryptographic, Algorithm Hash Function.]

Chapter 1- An overview of the basic concepts of cryptography

1-1-Introduction

Today, security is of great importance and is widely used in the economic and commercial environment. The types of solutions presented so far are of the type of data security. There are several reasons for data protection in any place and time, but in the real world, dealing with multiple cases of information theft and the possibility of passing required tests and audits has always been a concern for information security and encryption [1]. For this reason, various types of passwords are used for data to ensure data security in communication [1].

1-3- Types of attacks

1-3-1-            Changing information

In this type of active attack, information is attacked during transmission to the destination and the integrity of the data is lost. Upon receiving the information, the attacker modifies it or replaces it with other information. The destination also does not recognize this issue and uses the data. To prevent this type of attack, abstractor functions [1] are used [1].

1-3-2-              Impersonation

In this type of active attack, the attacker introduces himself as an authorized user to local systems and thus uses various local network services. Digital signatures are used to prevent these types of attacks and provide authentication of users and software. In this way, attackers prevent an institution from providing services. It is easy to set up this type of attack and it is often done using impersonation methods and sending large amounts of Internet Protocol systems [2]. These attacks are called DOS for short [3]; and are part of active attacks. These attacks can be reduced by using a firewall [1].

1-3-3-           Eavesdropping

   In this type of passive attack [4], the information is not changed, but their confidentiality is lost. If you want to send information in plain text and not encrypted to remote systems, then this information may be received by unauthorized persons. Extortion of information may be done in different places such as local networks, data transfer switches or the Internet. Now there are different software to get different information from the local network and viruses and attackers can also get the information transferred on a public network. To avoid this security problem, symmetric and asymmetric data encryption techniques are used [1].

1-4- Data encryption

Encryption is a process during which data is changed from its normal form and becomes almost impossible to read without having the necessary information (decryption); Therefore, in this method, by encrypting the data, unauthorized people are prevented from accessing the data and data confidentiality is obtained. In this method, encryption is done at the origin and then encrypted data is sent to the destination. An attacker who eavesdrops and receives data packets in transit over the network obtains encrypted data.An attacker who eavesdrops and receives data packets in transit over the network obtains encrypted data that is unusable to him. The recipient of the data at the destination also receives the encrypted data, but because he has the data decoding information, he can decode and use the data. There are two methods for data encryption, symmetric and asymmetric. The idea of ??symmetric encryption has existed for years and is not a new problem, but asymmetric encryption uses mathematical principles and complex algorithms and is considered a new method in data encryption [1]. It is also used to perform encryption operations using a common and secret key between the sender and the receiver. In this method, the data is encrypted at the source with a shared key and sent to the destination, and the data is decrypted with the shared key at the destination. In symmetric encryption, it is assumed that the attacker is aware of the encryption algorithm and relies only on the confidentiality of the shared encryption key. In general, the longer the key length, the more time it takes to break the data and the more security is obtained. Considering the current processing power, choosing more keys than 128 bits seems appropriate. Also, cryptographic keys should be changed after some time of use and new keys should be randomly selected even if possible to achieve maximum security. Symmetric encryption algorithms are divided into 2 categories: block algorithms [5] and stream algorithms, and data is encrypted or decrypted bit by bit. Stream algorithms are faster than block algorithms. Algorithms such as [6] DES are block and algorithms such as RCCL are streams, although it should be noted that symmetric encryption also provides authentication. If an encrypted data is received, according to the key used, the identity of the person sending the data can be confirmed because these keys are assumed to be confidential. Symmetric encryption has good efficiency and provides little delay in data encryption and decryption operations; Therefore, it can be used to encrypt a large amount of data. This type of encryption is widely used in wireless security protocols. Algorithm 3DES, DES, IDEA [7], RC4 [8], etc. are symmetric algorithms [1].

1-6- Asymmetric encryption of data

Asymmetric encryption or public key encryption is the biggest and perhaps the only revolution in the history of encryption. In this algorithm, instead of permuting and replacing data, mathematical functions are used, and instead of a shared secret key, a public key and a private key are created, and the public key is available to everyone and the private key is available only to the user. For private key confidentiality, a password to access the private key database is considered. The concept of public key cryptography was created after trying to solve the two problems of key distribution in a secure way and digital signature, and it has the following two important and basic characteristics. 1- It is computationally impossible to calculate the decryption key from the encryption key. 2- Both public and private keys can be used for encryption. Of course, another key must be used for decryption. In this encryption method, first the public key of the destination is provided in a valid way and then the data is encrypted and sent to it by the public key of the destination. The attacker between the origin and destination path can easily obtain the public key of the destination, but with this key, he will not be able to decrypt the data. At the destination, the data is decrypted and used by the private key. Of course, the reverse of this method does not create data confidentiality because if the data is first encrypted by the private key and then transferred because everyone knows the public key; Therefore, everyone can decrypt the encrypted data and the confidentiality of the data is lost. A digital certificate can be used to obtain the public key in an authentic way. Compared to symmetric encryption, this method uses complex and time-consuming calculations and is therefore not used to encrypt a large amount of data. Often this type of encryption uses symmetric encryption keys to send small amounts of data. The most common algorithm for encryption is the public key RSA algorithm [1].