Due to outsource manufacturing, the semiconductor industry must deal with various hardware threats such as piracy and overproduction. To prevent illegal electronic products from functioning, the circuit can be encrypted using a protected key only known to the designer. However, an attacker can still decipher the secret key utilizing a functioning circuit bought from the market, and the encrypted layout leaked from an untrusted foundry. In this paper, after introducing essential conformity and mutuality features for secure logic encryption, we propose DLE, a novel Distributed Logic Encryption design that resists against all known oracle guided and structural attacks including the newly proposed fault-aided SAT-based attack that iteratively injects a single stuck-at fault to thwart the locking effect. DLE forces the attacker to insert multiple stuck-at faults simultaneously in critical points to achieve a smaller but meaningful encrypted circuit; thus, exponentially reducing the chance to hit all the critical points with properly located stuck-at fault injections. Our experiments confirm that DLE maintains an exponentially high degree of security under diverse attacks with the polynomial area and linear performance overheads.
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Hardware functional obfuscation with ferroelectric active interconnects
Abstract Existing circuit camouflaging techniques to prevent reverse engineering increase circuit-complexity with significant area, energy, and delay penalty. In this paper, we propose an efficient hardware encryption technique with minimal complexity and overheads based on ferroelectric field-effect transistor (FeFET) active interconnects. By utilizing the threshold voltage programmability of the FeFETs, run-time reconfigurable inverter-buffer logic, utilizing two FeFETs and an inverter, is enabled. Judicious placement of the proposed logic makes it act as a hardware encryption key and enable encoding and decoding of the functional output without affecting the critical path timing delay. Additionally, a peripheral programming scheme for reconfigurable logic by reusing the existing scan chain logic is proposed, obviating the need for specialized programming logic and circuitry for keybit distribution. Our analysis shows an average encryption probability of 97.43% with an increase of 2.24%/ 3.67% delay for the most critical path/ sum of 100 critical paths delay for ISCAS85 benchmarks.
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- Award ID(s):
- 2008365
- PAR ID:
- 10327188
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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