2023
Authors
Almeida, JB; Barbosa, M; Barthe, G; Grégoire, B; Laporte, V; Léchenet, JC; Oliveira, T; Pacheco, H; Quaresma, M; Schwabe, P; Séré, A; Strub, PY;
Publication
IACR Trans. Cryptogr. Hardw. Embed. Syst.
Abstract
2021
Authors
Almeida, JB; Barbosa, M; Correia, ML; Eldefrawy, K; Lengrand, SG; Pacheco, H; Pereira, V;
Publication
IACR Cryptol. ePrint Arch.
Abstract
2021
Authors
Bacelar Almeida, JC; Barbosa, M; Eldefrawy, K; Lengrand, SG; Pacheco, H; Pereira, V;
Publication
CoRR
Abstract
2018
Authors
Almeida, JB; Barbosa, M; Barthe, G; Pacheco, H; Pereira, V; Portela, B;
Publication
IEEE 31ST COMPUTER SECURITY FOUNDATIONS SYMPOSIUM (CSF 2018)
Abstract
We give a language-based security treatment of domain-specific languages and compilers for secure multi-party computation, a cryptographic paradigm that. enables collaborative computation over encrypted data. Computations are specified in a core imperative language, as if they were intended to be executed by a trusted-third party, and formally verified against. an information-flow policy modelling (an upper bound to) their leakage. This allows non-experts to assess the impact of performance driven authorized disclosure of intermediate values. Specifications are then compiled to multi-party protocols. We formalize protocol security using (distributed) probabilistic information-flow and prove security-preserving compilation: protocols only leak what. is allowed by the source policy. The proof exploits a natural but previously missing correspondence between simulation-based cryptographic proofs and (composable) probabilistic non-interference. Finally, we extend our framework to justify leakage cancelling, a domain-specific optimization that allows to first write an efficient specification that fails to meet the allowed leakage upper-bound, and then apply a probabilistic preprocessing that brings leakage to the acceptable range.
2024
Authors
Almeida, JB; Olmos, SA; Barbosa, M; Barthe, G; Dupressoir, F; Grégoire, B; Laporte, V; Lechenet, JC; Low, C; Oliveira, T; Pacheco, H; Quaresma, M; Schwabe, P; Strub, PY;
Publication
ADVANCES IN CRYPTOLOGY - CRYPTO 2024, PT II
Abstract
We present a formally verified proof of the correctness and IND-CCA security of ML-KEM, the Kyber-based Key Encapsulation Mechanism (KEM) undergoing standardization by NIST. The proof is machine-checked in EasyCrypt and it includes: 1) A formalization of the correctness (decryption failure probability) and IND-CPA security of the Kyber base public-key encryption scheme, following Bos et al. at Euro S&P 2018; 2) A formalization of the relevant variant of the Fujisaki-Okamoto transform in the Random Oracle Model (ROM), which follows closely (but not exactly) Hofheinz, Hovelmanns and Kiltz at TCC 2017; 3) A proof that the IND-CCA security of the ML-KEM specification and its correctness as a KEM follows from the previous results; 4) Two formally verified implementations of ML-KEM written in Jasmin that are provably constant-time, functionally equivalent to the ML-KEM specification and, for this reason, inherit the provable security guarantees established in the previous points. The top-level theorems give self-contained concrete bounds for the correctness and security of ML-KEM down to (a variant of) Module-LWE. We discuss how they are built modularly by leveraging various EasyCrypt features.
2025
Authors
Santos, T; Grümer, P; Parsamehr, R; Pacheco, H;
Publication
2025 IEEE VEHICULAR NETWORKING CONFERENCE, VNC
Abstract
Electronic Control Units are embedded devices that control various critical features of an automobile. Consequently, it is crucial to develop tools that enable penetration testers to identify security vulnerabilities within these ECUs as efficiently as possible. Fuzzing, a widely-used technique, can help uncover vulnerabilities in various types of applications. Fuzzing can then be applied to test ECUs through their communication protocols, the most common being the Controller Area Network (CAN). We present oCANada, a generation-based fuzzer which can be utilized in order to craft CAN messages for fuzzing. Many existing CAN fuzzers rely on simple mutation-based fuzzing, which involves randomly changing bits in the CAN payload. This paper introduces a novel generation-based fuzzing approach that leverages CAN database files (DBCs) in order to craft syntactically correct messages. oCANada also incorporates State-of-the-Art CAN reverse engineering techniques in order to enable syntax-aware fuzzing even when DBCs are not available. Additionally, this paper discusses test oracle techniques employed for fuzzing ECUs over CAN in both greybox and blackbox environments. Finally, we present our results while running the tool which we used two CANoe simulations, a Gateway ECU, and a modified version of the instrument cluster simulator ICSim. In these results, we also compare our fuzzer to the well-known CaringCaribou fuzzer.
The access to the final selection minute is only available to applicants.
Please check the confirmation e-mail of your application to obtain the access code.