Securing Cryptographic Chips against Scan-Based Attacks in Wireless Sensor Network Applications

Abstract

Wireless sensor networks (WSN) have deeply influenced the working and living styles of human beings. Information security and privacy for WSN is particularly crucial. Cryptographic algorithms are extensively exploited in WSN applications to ensure the security. They are usually implemented in specific chips to achieve high data throughout with less computational resources. Cryptographic hardware should be rigidly tested to guarantee the correctness of encryption operation. Scan design improves significantly the test quality of chips and thus is widely used in semiconductor industry. Nevertheless, scan design provides a backdoor for attackers to deduce the cipher key of a cryptographic core. To protect the security of the cryptographic system we first present a secure scan architecture, in which an automatic test control circuitry is inserted to isolate the cipher key in test mode and clear the sensitive information at mode switching. Then, the weaknesses of this architecture are analyzed and an enhanced scheme using concept of test authorization is proposed. If the correct authorization key is applied within the specific time, the normal test can be performed. Otherwise, only secure scan test can be performed. The enhanced scan scheme ensures the security of cryptographic chips while remaining the advantages of scan design.

A robust packet‐dropping covert channel for mobile intelligent terminals

“…[48][49][50] Thus, covert channels can be used as a countermeasure for transmitting confidential information in unsecure mobile networks. [51][52][53][54][55][56] Covert channels can outmenuver network security measures and stealthily transmit a covert message. 57,58 CTCs are constructed on features like inter-packet delays, packet sequence, and transmission schedule.…”

“…IoT has brought numerous benefits, but they also present significant privacy threats 48–50 . Thus, covert channels can be used as a countermeasure for transmitting confidential information in unsecure mobile networks 51–56 . Covert channels can outmenuver network security measures and stealthily transmit a covert message 57,58 .…”

Data security sharing model based on privacy protection for blockchain‐enabled industrial Internet of Things

“…A policy-based file access control scheme is proposed in References. 26,27 This scheme implements confidential data exchange, shared data access control, and resolve conflicts. And the data access in this scheme can be audited and verified.…”

Scan‐based attack tolerance with minimum testability loss: a gate‐level approach

“…In Table 6, the proposed method is compared with other protecting methods including, MKR [10], round register masking [14], SDFF_100 [16], dynamic obfuscation lock & key [17], onchip comparison [18], PUF-based lock & key [20], dynamic-key [22], DOS [23], and key masking lock & key (ISSATCU) [25] in terms of probability of a successful attack and area overhead. As can be seen in Table 6, the proposed method offers the highest achieved security with the lowest imposed area overhead.…”

“…advanced encryption standard (AES) [10,[12][13][14], data encryption standard (DES) [9,11], and Rivest-Shamir-Adleman [15,16]. On the other hand, there are several countermeasures which attempt to protect crypto-chips against scan-based attacks in different ways such as mirror key register (MKR) [10], round register masking [14], state-dependent scan flip-flop (SDSFF) [15,16], dynamic obfuscation lock & key [17], on-chip key comparison [18,19], physically unclonable function (PUF)-based lock & key [20], dynamic scan [21], dynamic-key [22], dynamic obfuscation scan (DOS) [23], and key masking [24,25]. However, such countermeasures for scan-based attack tolerance suffer from one or more drawbacks which are described in the next section.…”