Assuring the quality and the trustworthiness of third party resources has been a hard problem to tackle. Researchers have shown that analyzing Integrated Circuits (IC), without the aid of golden models, is challenging. In this paper we discuss a toolset, NETA, designed to aid IP users in assuring the confidentiality, integrity, and accessibility of their IC or third party IP core. The discussed toolset gives access to a slew of gate-level analysis tools, many of which are heuristic-based, for the purposes of extracting high-level circuit design information. NETA majorly comprises the following tools: RELIC, REBUS, REPCA, REFSM, and REPATH.
The first step involved in netlist analysis falls to signal classification. RELIC uses a heuristic based fan-in structure matcher to determine the uniqueness of each signal in the netlist. REBUS finds word groups by leveraging the data bus in the netlist in conjunction with RELIC's signal comparison through heuristic verification of input structures. REPCA on the other hand tries to improve upon the standard bruteforce RELIC comparison by leveraging the data analysis technique of PCA and a sparse RELIC analysis on all signals. Given a netlist and a set of registers, REFSM reconstructs the logic which represents the behavior of a particular register set over the course of the operation of a given netlist. REFSM has been shown useful for examining register interaction at a higher level. REPATH, similar to REFSM, finds a series of input patterns which forces a logical FSM initialize with some reset state into a state specified by the user. Finally, REFSM 2 is introduced to utilizes linear time precomputation to improve the original REFSM.
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ReGDS: A Reverse Engineering Framework from GDSII to Gate-level Netlist
With many fabless companies outsourcing integrated circuit (IC) fabrication, the extent of design information recoverable by any third-party foundry remains clouded. While traditional reverse engineering schemes from the layout employ expensive high-resolution imaging techniques to recover design information, the extent of design information that can be recovered by the foundry remains ambiguous. To address this ambiguity, we propose ReGDS, a layout reverse engineering (RE) framework, posing as an inside-foundry attack to acquire original design intent. Our framework uses the layout, in GDSII format, and the technology library to extract the transistor-level connectivity information, and exploits unique relationship-based matching to identify logic gates and thereby, recover the original gate-level netlist. Employing circuits ranging from few hundreds to millions of transistors, we validate the scalability of our framework and demonstrate 100% recovery of the original design from the layout. To further validate the effectiveness of the framework in the presence of obfuscation schemes, we apply ReGDS to layouts of conventional XOR/MUX locked circuits and successfully recover the obfuscated netlist. By applying the Boolean SATisfiability (SAT) attack on the recovered obfuscated netlist, one can recover the entire key and, thereby, retrieve the original design intent. Thus ReGDS results in accelerated acquisition of the gate-level netlist by the attacker, in comparison to imaging-based RE schemes. Our experiments unearth the potential threat of possible intellectual property (IP) piracy at any third-party foundry.
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- Award ID(s):
- 1812071
- NSF-PAR ID:
- 10237619
- Date Published:
- Journal Name:
- IEEE International Symposium on Hardware Oriented Security and Trust (HOST)
- Page Range / eLocation ID:
- 154 to 163
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/HOST45689.2020.9300272
