DEC‐LADE: Dual elliptic curve‐based lightweight authentication and data encryption scheme for resource constrained smart devices

IET Wireless Sensor SystemsVolume 11, Issue 2 p. 91-109 ORIGINAL RESEARCH PAPEROpen Access DEC-LADE: Dual elliptic curve-based lightweight authentication and data encryption scheme for resource constrained smart devices Vidya Rao, Vidya Rao Department of Computer Science and Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, IndiaSearch for more papers by this authorPrema K. V., Corresponding Author Prema K. V. prema.kv@manipal.edu Department of Computer Science and Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, India Correspondence Prema K. V., Department of Computer Science and Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, India. Email: prema.kv@manipal.eduSearch for more papers by this author Vidya Rao, Vidya Rao Department of Computer Science and Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, IndiaSearch for more papers by this authorPrema K. V., Corresponding Author Prema K. V. prema.kv@manipal.edu Department of Computer Science and Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, India Correspondence Prema K. V., Department of Computer Science and Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, India. Email: prema.kv@manipal.eduSearch for more papers by this author First published: 14 February 2021 https://doi.org/10.1049/wss2.12014Citations: 1AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract The fast growth in Internet-of-Things (IoT) applications has increased the number of end-devices communicating over the Internet. As these resource-constrained devices are connected over the Internet, they are exposed to various security and privacy issues. Traditionally, to provide end-to-end security, research efforts have been carried out using elliptic curve cryptography-based authentication schemes. These existing schemes use a single set of elliptic curve parameters to generate the public and private keys, which are prone to be hacked under intense cryptanalysis. Thereby to increase the security strength the proposed method uses two sets of dynamic elliptic curves for performing digital signature and encryption processes. The method is evaluated on a client-server model using the Raspberry Pi-3 device. Herein, the choice of elliptic curves is made random at the client node and the reference of each elliptic curve is exchanged with the server during the key-exchange process. The choice of elliptic curves is delegated to the client machine to avoid the unwanted delay that would be encounter if server had to choose the curve. This is done because the client senses the data at regular intervals of time and forwards it to the server securely. Experiments were conducted to measure the time taken for hashing function, key generation, signature generation, signature verification, encryption and decryption process. On comparing the proposed DEC-LADE with cBLAKE2b, an improvement was seen at 13.76%, 2.57%, 18.36%, 6.12%, 9.91% and 6.08% less time, respectively, than LWDSA with mBLAKE2b. Theoretical and real-time security evaluations are performed for man-in-the-middle attack, replay attack, and a denial-of-service attack. 1 INTRODUCTION Internet-of-Things (IoT) is a self-organising, self-adaptive and intelligent network that has its applications ranging from smart cities to smart agriculture. With the huge breakthrough in the Internet connected devices having Radio Frequency Identifier (RFID) based sensors to complex automation-based sensors, a wide variety of objects are communicating over the Internet [1] and they exchange huge among of different type data. Thereby, with the vision of creating a heterogeneous system of millions of connected objects that can communicate securely over the Internet, IoT has opened challenges under the security and privacy of the user data and personal user credentials [2,3]. A single node of IoT comprises a sensing unit, actuation unit, power unit, memory unit and communication model. Each object is equipped with a simple 8/16/32-bit micro-controller that is weak and insecure. Thereby, using such end-points, a hacker can launch cyber-attack against the network. Hence, it is essential to develop an efficient encryption and authentication schemes for protecting the resource-constrained on-board embedded devices [4,5]. In Ref. [6], Elliptic Curve Cryptography (ECC) is proved to be appropriate for 8-bit CPU system against RSA. Due to this, Elliptic Curvey Digital Signature Algorithm (ECDSA) is used to ensure authentication of the user in various applications. Currently, ECC-based schemes use Weierstrass Curve equation [7] and they run under single static curve values, that is a single set of curve parameters are used for whole of the communication. The authors of Ref. [8] have analysed the need for using different curves to increase the strength of cryptanalysis. Based on the work suggested in Ref. [8], a secured lightweight method to ensure authentication and data integrity is proposed which uses two different sets of Weierstrass Curve values for signature and encryption process. Under the laboratory conditions, the proposed system is executed on a Raspberry Pi-3-based network and the results are compared with the method proposed in Ref. [9]. In this work, an Elliptic Curve Cryptography (ECC)-based lightweight authentication and encryption scheme is proposed that addresses both the authentication of the user and data integrity issues of IoT security. Initially, a registration phase is developed where the client node gets registered with the server node. During this phase, the time taken for registration is calculated under cBLAKE2b [10] and mBLAKE2b [9]. Later, a novel elliptic curve selection and key generation process is proposed wherein the client node chooses a pair of elliptic curves from tested curves stored in its database and generates the curve points. Then it shall generate public and private keys using different elliptic curves (level-1 and level-2). During the public key exchange with the server, the chosen elliptic curve identities are forwarded to the server. Then server checks the identities of curves obtained and matches the curves from its own repository and generates public and private keys for both the levels. Later, the client node generates signatures using proposed ECDSA algorithm and level-1 public and private keys and encrypts the hash value of the message and the raw message using level-2 keys. The signature pair and the public key of the server are concatenated. During every contention phase, a unique integer value of 8-bit long is added at the beginning and end of the inputs to increase the security of the data, and at the server, the decryption process is executed first and then the signatures are verified. The proposed scheme is compared for time efficiency with Ref. [9] by using the elliptic curve equation y2 = x3 + ax + b and a large number as private key of 192-bits in length. The experiment was conducted under the laboratory environment for an application of the weather data logging system, using Raspberry Pi 3 model, a temperature sensor (DHT-11) and a carbon dioxide sensor (MQ-135). The application was programmed to collect the change in temperature, humidity and carbon dioxide for various intervals of time and the collected data was subjected as input for the proposed digital signature and encryption methods to be evaluated. The proposed scheme is evaluated on a client-server model by using three Raspberry Pi 3 (RPi3) machine. One RPi3 acts as a client machine and is designed as weather data logging system and the other RPi3 is used as a server machine with high storage capacity. The third RPi3 is used as an attacker machine with Kali Linux as operating system. The research contribution is summarised as: The proposed DEC-LADE with cBLAKE2b has shown 13.76%, 3.32% and 7.79% faster execution in message digest calculation when compared with other combinations such as, LWDSA with mBLAKE2b, LWDSA with cBLAKE2b and DEC-LADE with mBLAKE2b. DEC-LADE with cBLAKE2b has shown a 17.24% to 18.83% faster signing time than the other combinations. During the signature verification time analysis, DEC-LADE with cBLAKE2b has shown an overall faster execution of 5.11% to 6.12% than compared with other combinations. DEC-LADE has also shown less time consumption under encryption and decryption with cBLAKE2b than mBLAKE2b. Also, DEC-LADE with cBLAKE2b has taken about 6.63% to 9.91% less time than DEC-LADE with mBLAKE2b during encryption process and 4.55% to 6.08% less time during decryption process. Under registration phase the proposed method with cBLAKE2b showed a time efficiency of 17.1–36.2%. Similarly during key exchange phase, the proposed system took considerably less time than that of Ref. [9] with an improved time efficiency of 6.37–9.47%. The security of the proposed schemes were verified by generating live attacks using Kali Linux hacking tools and thereby the method showed resistance against denial-of-service (DOS) attack, replay attack and man-in-the-middle (MITM) attack. The remaining part of this article is organised as follows: Section 2 provides the related works with their drawbacks. Section 3 describes the basics of elliptic curve cryptography, cBLAKE2b, Kali Linux and security attacks considered for real-time evaluation under background. Section 4 states the system design and problem definition of the proposed methodology. Section 5 explains in detail the proposed model. Section 6 explains the implementation and performance analysis followed by theoretical and real-time security evaluation under Section 7. Finally, the conclusion of the proposed work along with possible future directions are stated in Section 8. 2 RELATED WORK We classify the related work into two sub-sections. In the first sub-section we discuss the various ECC-based methods used for resource constrained devices and in the second part we discuss the different Kali Linux-based real-time attack models. 2.1 Elliptic curve cryptography-based security schemes This section describes the history of ECC and some of the authentication protocols that uses ECDSA algorithms. During 1985, Neal Koblitz and Victor Miller introduced ECC [11]. They stated that the security strength of ECC depends over the discrete logarithmic problem (DLP) defined on the elliptic curve Eq. On an 8-bit CPU, Gura et al. [6] performed experiments between ECC and Rivest, Shamir, Adleman (RSA) algorithms. Through their experiments, they concluded that the use of ECC provided same level of security as of RSA for a lower bit processors. Then in 2013, an ECC-based access control scheme was proposed by Wenger [12] over the prime field of an 16-bits MSP430 micro-controller. From his study he realized the feasibility of ECC for resource-constrained devices. Traditionally, all the participants of the network are distributed with static elliptic curve parameters during any ECC-based communication. The commonly used elliptic curve parameter are recommended in Ref. [13]. These elliptic curve follow the equation y2 = x3 + ax + b [14] called as Weierstrass curve equation. Furthermore, Lie et al. [15] and Wenger et al. [12] have shown the feasibility of ECC on the embedded system and discovered the disadvantage of using fixed elliptic curve. To address the issue pertaining to use of the static elliptic curve in ECC-based cryptography, Jia Wang et al. [8] have designed a dynamic elliptic curve concept for Internet-of-Vehicular (IoV) network. From their work it is observed that dynamic choice of elliptic curve parameters provides good computational efficiency and high security for a smaller key size. But storing the elliptic curve parameters as a plain text in the embedded system memory would lead to security concern. In 2017, for an Wireless Sensor Networks (WSN) environment, Lavanya and Natarajan [9] have proposed a lightweight authentication scheme using mBLAKE2b as the hashing method for ECDSA-based authentication scheme. Their method was studied for performance parameters like energy consumption, throughput, latency, packet delivery ratio and signature verification using NS-2 simulator. The security of the method was evaluated using SCYTHER tool [16]. Through the result analysis, they have shown a better performance of the authentication process when compared with traditional authentication schemes. But the work is not adaptable for a scalable network. An ECC-based lightweight heterogeneous hybrid signcryption scheme was introduced by Rahman et al. [17] in 2018. The issue of multi-message encryption is resolved by using hyper-elliptic curves. The security of the scheme was inspected by using the AVISPA simulation tool [18] and it showed resistance against replay, integrity, secrecy, unforgeability and confidentiality attacks. Premila et al. [19] proposed a security framework for IoT and cloud computing. They used ECC-based multi-factor authentication and message encryption to provide integrity, confidentiality, privacy and user authentication. They have compared ECC and RSA and found ECC security measures are better to eliminate the ambiguity and enhance the security of the data. But the collaboration of IoT and cloud computing lacked in standardisation of the infrastructure. Jingwei et al. [20] have proposed a novel secure authentication scheme for heterogeneous IoT environment. The simulation of anonymous mutual authentication and key agreement scheme has shown resistance against a replay attack and DOS attack. In 2020, Diaz et al. [21] have presented an ECC-based multifactor authentication by integrating High-Performance Computing (HPC) with the cloud system. Their work was evaluated on the system-on-chip ESP32 that provided an extra layer of security between HPC and the cloud system. The elements communicated eTokens using Message Queuing Telemetry Transport (MQTT). The proposed system has shown good resistance against various know attacks. The work is evaluated for HPC systems, which has a good amount of resources. Al-Zubaidie et al. [22] have proposed an ECDSA-based solution for health WSN (HWSN) called Reliable and Efficient Integrity Scheme for Data Collection in HWSN (REISCH). Their work has shown good efficiency in data integrity between sensors and the server. The work is simulated under NS2 and performance analysis is compared between SHA and BLAKE hash functions under ECDSA. The security strength of the work is checked using the AVISPA simulation tool. Under AVISPA, their work has shown resistance against well-known attacks. Even though the work is evaluated for data integrity, authentication of the users is unattended and practical implementation of the work has to be performed. From Table 1, it is observed that, the existing ECC-based schemes lack in providing resistance against major IoT attacks. Likewise, the existing works are evaluated for their resistance towards security attacks either by theoretical or simulated using ASIVPA/SCYTHER tools. Thus, there is a need of real-time evaluation of performance and security strength of any security schemes that are presented for resource-constrained devices. TABLE 1. Summary of related work with respect to the types of attacks evaluated Node Replay Data Evaluation MITM Compromise Attack DOS Integrity Tool Lavanya and Natarajan [9] Yes Yes Yes - - Simulation and theoretical Rahman et al. [17] - Yes Yes - Yes Simulation and theoretical Premila et al. [19] - Yes - Yes - Jingwei et al. [20] - - Yes Yes - Theoretical Diaz et al. [21] Yes Yes - Yes - Simulation Zubaide et al. [22] Yes - Yes Yes - Simulation 2.2 Kali Linux-based real-time attack models Considering the quick developments of smart cities, researchers have done various investigations on the increase in the smart city-based applications and number of security breach over the business by 2050. To identify the attacks on these smart devices, Nedaa et al., and Yittu et al. [23] have proposed various Kali-Linux-based vulnerability assessment and penetration testing solutions. Their experiments were conducted on low-cost Raspberry Pi-3 devices. Through the results obtained, it is observed that Raspberry Pi-3 devices can be used as a vulnerability check machine similar to any traditional PC or laptop running Kali Linux. They have made the analysis on different dimensions such as CPU usage, CPU temperature and memory utilization at the time of vulnerability test. For IoT devices, a graphical interface-based penetration testing tool termed as PENTOS was introduced by Vasaka et al. [24]. PENTOS uses Kali Linux OS and is designed for the ethical hacking of wireless communication technologies like WiFi and Bluetooth. PENTOS helps to analysis of various network attacks like web attack, password attack and wireless attacks that ensure to gain access privilege of the various algorithms. Finally, Vasaka et al., have provided few recommendations for the secure deployment of the IoT environment based on Open Web Application Security Project (OWASP). To perform penetration testing for private network, Mathew et al. [25] and Lulu et al. [26] have designed Kali Linux-based attack test-beds. They experimented various attacks on Raspberry Pi-based Kali Linux and were able to generate attack reports and visualise the reports using Kali Linux tools. Some of the attacks they executed are various DOS attacks, MITM attack, smart-phone penetration, hacking phones and phone's Bluetooth, spying, hacking Wi-Fi Protected Access (WPA) points and then they could hack the remote PC using IP and open ports. Further to this, Ryan Murray [27] has designed a secure eHealth solution called HealthShare. HealthShare application could share data among various organisations that were hosting the patient's data over the cloud. He has provided a detailed step to conduct attacks like MITM and DOS attack using tools like Ettercap, manual SET, pExpect, Nmap timer, threads using the timer and Scapy tool available in the Kali Linux. Soe et al. [28] designed a lightweight detection system based on machine learning methods. The work is implemented on a Raspberry Pi device and the performance is verified for a public dataset collected from a real-time IoT environment. A lightweight feature selection algorithm called correlated-set thresholding on gain ration (CST-GR) algorithm was used. They have executed their work for different machine learning algorithms for three kinds of cyber-attacks to verify the system's best option. A Raspberry Pi-based adversary model is proposed by Gupta et al. [29] for demonstrating MITM attack. They have created a rogue wireless access point that captures critical user information. The analysis is done for the different operating system and application log files. Some of the tools they have used are FTK Access Data, Autopsy, and Bulk Extractor. 3 BACKGROUND In this section, a brief study of ECC is explained along with the working of cBLAKE2b and method proposed in Ref. [9]. Later, a summary of Kali Linux-based tools is explained with various attacks considered for security analysis of the proposed method. 3.1 Overview of ECC The Public Key Cryptography (PKC) is used in solving numerous computational problems. The most commonly used algorithms are Rivest-Shamir-Adleman (RSA), El-Gamal-based digital signature and encryption and Elliptic Curve Cryptography (ECC)-based digital signature and encryption [7,30]. ECC was viewed as an elliptic curve analogous of the older discrete logarithmic (DL) cryptosystem proposed by Victor Miller and Neal Koblitz [11]. The strength of ECC depends on Elliptic Curve Discrete Logarithmic Problem (ECDLP) [11] where ECDLP states that, by considering an elliptic curve: y2 = x3 + ax + b, with 4a3 + 27b2 ≠ 0, and for a given two elliptic curve point Q and a large prime number k it is easy to calculate P = k*G using scalar multiplication. But it is computationally in-feasible to calculate the value of k when P and Q are known. This makes the ECDLP problem stronger. Basically, elliptic curve is defined over parameters as T = (p, a, b, G, n, h), where ‘p’ is a prime number on the field Fp, (a,b) are EC parameters, ‘G’ is a generator point and ‘n’ is the order of ‘G’ and ‘h’ is the co-factor defined as h = E(Fp)/n. It operates on two sets of fields: primary field Fp and binary field F2m. ECC is used for key generation, digital signature and encryption. The variants are ECC are Diffie-Hellman Algorithm (ECDHA) [7], ECC-based digital signature (ECDSA) [31, 32] and ECC-based encryption is called as Elliptic Curve-based Integrated Encryption Scheme (ECIES) [33]. Among the variants, ECDSA is commonly used digital signature algorithm that was proposed by Scott Vanston [32] as a response to the National Institute of Standard and Technology (NIST) request on public comment on existing digital signature. ECDSA involves inverse calculation which is expensive in modular arithmetic. Thereby, in the proposed system the computation of inverse is done during key pair generation phase and not in signing phase. By doing this, the key will remain constant for a stable period of time as the signing process can be done more frequently than key generation. This will save time and computational cost of the ECDSA. To enhance the data integrity, similar to the ECC-based encryption scheme proposed during 1997 by Bellare, and Rogaway proposed Discrete Logarithm Augmented Encryption scheme (DLAES) which was later improved by various researchers to obtain an updated version called Elliptic Curve Integrated Encryption Scheme (ECIES). As the name suggests, ECIES is an integrated encryption scheme that uses functions like key agreement (KA), key derivation function (KDF), encryption (ENC), hashing function (HASH) and a message authentication code (MAC) [7]. A similar process is used to encrypt the data under the proposed scheme along with the ECDSA to enhance the security of the proposed framework. 3.2 cBLAKE2b Federal Information Processing Standards (FIPS) proposed a hash algorithm that generated a condensed representation of a message. They define a cryptographic hash function H as a function that takes input of the variable size and produces an output of fixed length bit string [34]. Hash functions can be used for message authentications, digital signatures, pseudorandom bit generators, and to create a one-way password file, key derivation functions and intrusion and virus detection systems. Primarily, Merkle and Damgard (MD5) [7] and versions of secure hash algorithms (SHA) [35,36] were used. Later in 2012, SHA announced the top five finalists of SHA-3 competition as KECCAK, BLAKE, Grostl, JH and Skien [37]. Even though KECCAK won the SHA3 competition during the course of research BLAKE showed a better performance with respect to speed and space complexity [38]. But Preneel [39] observed that BLAKE's security and efficiency could be ruled out with an extensive crypt-analysis. Thus he pointed the need for improved BLAKE and hence proposed a new version as BLAKE2. In Ref. [10], an improved version of BLAKE2b is proposed as customised BLAKE2b (cBLAKE2b). cBLAKE2b does not use the parameter block of BLAKE2b and also the rotation function G(a,b,c,d) is rearranged to ensure that cBLAKE2b is secured and performs better than BLAKE2 for resources-constrained devices. cBLAKE2b works under hash iterative function (HAIFA) model mentioned in Ref. [40]. The proposed work uses cBLAKE2b and the Ref. [9] method uses mBLAKE2b. Also, cBLAKE2b has satisfied the security concern of one-way hash function such as: pre-image resistance, secondary pre-image resistance and collision resistance [10]. 3.3 Lightweight digital signature algorithm (LWDSA) LWDSA was proposed by Lavanya and Natarajan [9] for the wireless sensor networks (WSNs)-based authentication. In WSN, each node performs authentication over the communication link between themselves and the sink node. Due to the limited resources in such nodes, it is necessity to use a lightweight authentication scheme. With this as the concern, they have proposed a ECSDA-based authentication scheme that uses mBLAKE2b as the hash function. In mBLAKE2b, the author has made modification by removing the standard initial vector (IV) and the salt value. They have used the first initial message value as IV and due to this change there is possibility of obtaining the message under strong crypt-analysis. The work is divided into three phases: the registration phase, the key agreement phase and the authentication phase. Among which, under the authentication phase they have two type of authentication: node to node and node to base station. The work is evaluated using NS-2 simulator with 30 nodes in the WSN environment and have obtained results for computational time for signature generation and verification, network latency, network lifetime, energy consumption and packet delivery ratio. The method was formally analysed for the strength of mBLAKE2b and also for the security attacks like Distributed Denial of Service (DDoS), Man-In-The-Middle (MITM) attack, replay attack and key revocation attack. With all the simulation results, their work was unable to show similar performance on a real-time scenario. Thereby, the methodology proposed in Ref. [9] was executed under the proposed environment and the results are analysed in Section 6.2. 3.4 Kali Linux Kali Linux is an operating system majorly used in ethical hacking and penetration testing. Kali Linux was introduced by Mati Aharoni and Devon Kearns of Offensive Security. It was designed mainly to suffice suitable environment for performing for digital forensic and penetration testing [41]. Kali Linux possess around 300 and odd hacking tools. These tools are broadly classified under vulnerability analysis, information gathering, web application, sniffing and spoofing tools, wireless attacks, exploitation tools, forensic tools, password attacks, access maintaining, hardware hacking tools and reverse engineering. Among these, the commonly used tools are metasploitable framework, dsniff, arpspoof, tcp dump, Nmap, Armitage, Wireshark, Burp suite, BeEF, Aircrack-ng, and so on [41,42]. 3.5 Security attacks considered IoT devices communicate over the public channel that are open to various internal and external threats such as (a) defective manufacturer, (b) malicious node in the network and (c) external adversary [43,44]. Such threats are open to security attacks that can be caused either by natural or man-made. Some of the natural threats are earthquake, floods, fire, and hurricane that causes severe damage to the computer system and are hard to safeguard. Thus to reduce the damage caused by natural threats, it is necessary to collect backup of data through contingency plan. Similarly, the security attacks that are man-made affects the data and user privacy [45,46] and can be further subdivided into information-level attacks, adversary-location attacks, access-level attacks and host-based attacks. The three different attacks that are consider for our experiment are explained below. 3.5.1 Man-in-the-middle attack MITM is a type of information level attack where the adversary takes control of an existing communication channel between two endpoints [47]. Here the adversary shall split the communication channel using different tools like arp spoofing, packet creator, dsniff, Ettercap and so on. When various packet sniffing and spoofing tools are used systematically, the communication between the genuine users can be entirely transparent for the adversary. Thereby, MITM attack is also referred to as connection hijacking attack, fire-bridge attack, or eavesdropping attack [48]. 3.5.2 Message replay attack A replay attack is a type of security breach wherein a malicious node captures the packets that are transmitted between the genuine user and then fraudulently delays or resends to the receiver [7,49]. To perform such an attack, the attacker need not possess any advanced skills to decrypt the message after capturing. Replay attack can be performed either by port stealing, which is an Ethernet-based and reconfiguration attack, which is a discovery and configuration protocol (DCP)-based and also using ARP request replay attack. But we have proposed our own way to detect the replay attack to our proposed setup using Wireshark to capture the message and send it back to server after a time-lapse as explained in Section 7.4. 3.5.3 Denial-of-service attack DOS is an attack over the network components that disables a server from lending the service to client machines [7,50]. Practically, a DOS attack is performed to prevent legitimate users from accessing resources. DOS attack targets either bandwidth or the connectivity of the network. Under a bandwidth-based DOS attack, the work is flooded with a vast amount of junk packets making the path busy and avoiding legitimate users access the system. Similarly, in connectivity-based DOS attack, the server is bombarded with a large volume of connectivity requests, thus consuming all the available operating system (OS) resources and disabling the genuine user netwo