Description
Embedded devices face software and physical fault injections to either extract or tamper with code in memory. The code execution and code intellectual property are threatened. Some existing countermeasures provide Control Flow Integrity (CFI) extended with the confidentiality and integrity of the instructions by chaining all of them through a cryptographic encryption primitive. While tampering with instructions in memory is prevented, fault injection attacks can still target the microarchitecture. In this talk, we introduce a new chained instruction encryption scheme with associated control signals, to provide additional authenticity and integrity properties down to the control signals of the microarchitecture’s pipeline. The instructions are stored encrypted in memory. At runtime, prior to being executed, the fetched instructions are decrypted depending on the control signals in the pipeline and all the previously decrypted instructions. In case of fault injections, targeting either instructions or control signals, the decryption process fails and generates random instructions, instead of the original ones. This quickly leads to an invalid instruction exception: the fault attack is thwarted. Our scheme was implemented on FPGA, into the 4-stage pipeline of the RISC-V cv32e40p core, using Ascon for encryption/decryption.
Infos pratiques
Prochains exposés
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Fine-grained dynamic partitioning against cache-based side channel attacks
Orateur : Nicolas Gaudin - Trasna
The growth of embedded systems takes advantage of architectural advances from modern processors to increase performance while maintaining a low power consumption. Among these advances is the introduction of cache memory into embedded systems. These memories speed up the memory accesses by temporarily storing data close to the execution core. Furthermore, data from different applications share the[…]-
SemSecuElec
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Micro-architectural vulnerabilities
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Hardware architecture
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Side-Channel Based Disassembly on Complex Processors: From Microachitectural Characterization to Probabilistic Models
Orateur : Julien Maillard - CEA
Side-Channel Based Disassembly (SCBD) is a category of Side-Channel Analysis (SCA) that aims at recovering information on the code executed by a processor through the observation of physical side-channels such as power consumption or electromagnetic radiations. While traditional SCA often targets cryptographic keys, SCBD focuses on retrieving assembly code that can hardly be extracted via other[…]-
SemSecuElec
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Side-channel
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Hardware reverse
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PhaseSCA: Exploiting Phase-Modulated Emanations in Side Channels
Orateur : Pierre Ayoub - LAAS-CNRS
In recent years, the limits of electromagnetic side-channel attacks have been significantly expanded.However, while there is a growing literature on increasing attack distance or performance, the discovery of new phenomenons about compromising electromagnetic emanations remains limited. In this work, we identify a novel form of modulation produced by unintentional electromagnetic emanations: phase[…]-
Side-channel
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