The repository implements the Fast Large-Scale Honest-Majority MPC for Malicious Adversaries article.
Abstract. Protocols for secure multiparty computation enable a set of parties to compute a function of their inputs without revealing anything but the output. The security properties of the protocol must be preserved in the presence of adversarial behavior. The two classic adversary models considered are semi-honest (where the adversary follows the protocol specification but tries to learn more than allowed by examining the protocol transcript) and malicious (where the adversary may follow any arbitrary attack strategy). Protocols for semi-honest adversaries are often far more efficient, but in many cases the security guarantees are not strong enough. In this paper, we present new protocols for securely computing any functionality represented by an arithmetic circuit. We utilize a new method for verifying that the adversary does not cheat, that yields a cost of just twice that of semi-honest protocols in some settings. Our protocols are information-theoretically secure in the presence of a malicious adversaries, assuming an honest majority. We present protocol variants for small and large fields, and show how to efficiently instantiate them based on replicated secret sharing and Shamir sharing. As with previous works in this area aiming to achieve high efficiency, our protocol is secure with abort and does not achieve fairness, meaning that the adversary may receive output while the honest parties do not. We implemented our protocol and ran experiments for different numbers of parties, different network configurations and different circuit depths. Our protocol significantly outperforms the previous best for this setting (Lindell and Nof, CCS 2017); for a large number of parties, our implementation runs almost an order of magnitude faster than theirs.
The protocol written in c++ and uses c++11 standard. It uses libscapi.
For libscapi installation instructions, visit here.
After you installed libscapi, run cmake . && make
The protocol designed for at least 3 parties.
To run the the protocol open a terminal and run:
run_protocol.sh <min_party_id> <max_party_id> <number_of_parties> <input_file> <circuit_file> <filed type> <parties_file> <number_of_iterations>
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field_type can be one of this values:
- ZpMersenne31
- ZpMersenne61
- ZpKaratsuba
- GF2m
- Zp
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parties_file - a file that contains the ip addresses and the port of all the parties. An example file can be found here.