construct oblivious transfer

Non-interactive oblivious transfer (OT) and one-round secure two-party computation (2PC) are impossible in classical models without strong assumptions such as trusted hardware, quantum random oracles (QROM), or pre-shared entanglement. Method: This work constructs the first unconditionally secure, two-message non-interactive OT, one-time programs (OTPs), and one-time memories (OTMs) in the noisy quantum storage (NQS) model—relying solely on its physical limitations. We integrate quantum error-correcting codes, one-time functions, and Yao-style garbled circuit compilation, assuming only semi-honest adversaries. Contribution/Results: Our protocols achieve true round optimality—one round for both OT and general 2PC—breaking the long-standing round-complexity lower bound. They are the first unconditionally secure, non-interactive OT and universal 2PC schemes in a physically plausible quantum model. This establishes a new paradigm for post-quantum cryptography and lightweight secure computation, eliminating reliance on idealized cryptographic primitives while preserving information-theoretic security.

This work addresses the inefficiency of traditional oblivious transfer (OT) protocols in resource-constrained environments such as the Internet of Things (IoT), where high computational overhead and multiple interaction rounds hinder practical deployment. The authors propose a novel 1-out-of-2 OT protocol based on the quadratic residuosity assumption, featuring an offline/online two-phase design that shifts the online computational burden to the sender and reduces interaction to six messages and four hashes. To the best of the authors’ knowledge, this is the first client-optimal OT protocol tailored for IoT devices. Under a 3072-bit RSA modulus, a single online OT execution requires only 39.90 microseconds—over ten times faster than SimplestOT—while significantly lowering both computational and communication costs for the receiver without compromising security.

This work addresses the inefficiency of unconditionally binding commitment schemes in quantum oblivious transfer (qOT). We propose an efficient string commitment scheme based on generic one-way functions (OWFs), breaking away from the conventional bit-by-bit commitment paradigm. To our knowledge, this is the first extension of Naor-type commitments to 2-bit string commitments. We design an interactive protocol with preprocessing that preserves information-theoretic binding while substantially reducing communication and computational overhead. Theoretical analysis shows that the communication cost for committing to a 2-bit string is reduced by approximately 50%, and online commitment generation becomes nearly constant-time after preprocessing. Crucially, the scheme operates without random oracles, achieving a favorable balance among security, practicality, and scalability—thereby opening a new avenue for efficient qOT implementations.

This work investigates security enhancement and fundamental limits of quantum Rabin oblivious transfer (ROT). In ROT, the receiver learns the sender’s bit with probability 1/2, and parties exhibit asymmetric cheating incentives. We introduce a novel security framework based on “deception advantage,” establishing—for the first time—the tight constant lower bound of 1/2 on cheating probability for any quantum ROT protocol. Our methodology integrates quantum information theory, game-theoretic modeling, and rigorous probabilistic analysis to construct a new quantum ROT protocol achieving this bound. Key contributions are: (1) the first quantum security analysis paradigm tailored to asymmetric cryptographic primitives; (2) a proof that the 1/2 bound is tight and optimal under ideal quantum conditions; and (3) a protocol whose security strictly surpasses all known classical and quantum ROT constructions.

This work addresses the separation problem between quantum commitments and quantum one-wayness: Does there exist a relativized world (relative to a quantum oracle) where quantum commitments exist, yet no efficiently verifiable quantum one-way state generator (QOWSG) does? The authors construct such a relativizing separation in the quantum oracle model—establishing, for the first time, that quantum commitments are strictly weaker than quantum one-wayness and refuting their black-box equivalence. Technically, they combine black-box reduction analysis, the quantum no-cloning theorem, and computational indistinguishability to design a novel oracle that strongly obstructs any QOWSG while preserving the security of quantum commitments. This result identifies quantum commitments, EFI (efficiently samplable, computationally indistinguishable) ensembles, quantum oblivious transfer, and secure multi-party computation as a class of minimal cryptographic primitives independent of quantum one-wayness—thereby clarifying their foundational role as the weakest assumptions in the hierarchy of quantum cryptographic primitives.

This work investigates the cryptographic underpinnings of anti-commuting operator tests in classically verifiable quantum computation and introduces a framework termed the Test of Non-Commutativity (ToNC). By establishing rigorous reductions between ToNC and classical key agreement (KA) as well as oblivious transfer (OT) based on one-way functions, the paper demonstrates for the first time that ToNC can be used to construct KA and implement OT. Furthermore, it introduces a post-quantum hardcore measure theorem and an interactive XOR lemma, enabling hardness amplification for KA and OT in post-quantum settings. These results uncover a deep connection between quantum verification protocols and classical cryptographic primitives, thereby laying a new theoretical foundation for classically verifiable quantum computation.

This study addresses the robustness and leakage-resilient security challenges of device-independent oblivious transfer (DI-OT) in quantum settings. Building upon post-quantum one-way functions, it constructs DI-OT and bit commitment using only trusted classical computation to control untrusted quantum devices. The work introduces a unified protocol framework compatible with both isolated and adaptive leakage models, integrating key techniques including parallel repetition bounds for the Magic Square game, affine consistency checks, and multi-round threshold theorems. It achieves simulation-based security and sequential composition, establishing DI-completeness to support secure computation of arbitrary classical functionalities. Furthermore, the authors construct efficient simulators and DI coin flipping with abort using polynomial device complexity, yielding a provably secure general-purpose computation scheme against static corruption.

This study investigates whether the classical UC security of (O)EKE and the Masny-Rindal compiler remains valid in post-quantum settings. Employing the Universal Composability framework under quantum polynomial-time adversaries, the authors utilize cryptographic reduction techniques to reveal inherent extraction barriers. This work proves that these protocols fail to achieve quantum UC security even when instantiated with post-quantum KEMs, presenting adversarial strategies that preclude simulation-based extraction. Concurrently, it establishes their game-based security by introducing a tightly bounded one-way hiding lemma. These results bridge critical theoretical gaps in the post-quantum security analysis of PAKE and oblivious transfer protocols.

This work addresses a critical gap in the foundations of Proofs of Space (PoS) by presenting a general framework that establishes their security under standard complexity-theoretic assumptions, thereby eliminating reliance on the random oracle model or ad hoc cryptographic hypotheses. For the first time, PoS security is reduced to the conjunction of classical complexity assumptions—such as the exponential hardness of E against nondeterministic circuits—and standard cryptographic primitives, including collision-resistant hash functions and SNARGs for languages in P. The framework yields succinct and non-trivial PoS constructions under relatively mild assumptions, and achieves near-optimal parameters and communication efficiency when instantiated under stronger complexity-theoretic conjectures.

This work proposes the first quantum one-time signature scheme implemented at the circuit level without computational assumptions, supporting applications such as delegated signing, secure token transfer, and publicly verifiable randomness. The scheme employs a classical public key and quantum secret key structure, leveraging superpositions of random affine cosets, puncturable pseudorandom functions, and coset membership testing circuits to achieve security against both classical and quantum polynomial-time adversaries while requiring only classical verification. It achieves a logical qubit count of Θ(κ log r + n + l) and gate complexity of Θ(n³ + nl), with a detailed quantification of quantum resource overhead under varying parameters, thereby balancing security and efficiency.