scl-rs

scl-rs is a port of the Secure Computation Library to Rust. scl-rs has a set of utilities for prototyping secure multiparty computation protocols (MPC).

scl-rs provides the following features:

• Traits for finite field arithmetic and an implementation of Mersenne61.
• Communication point-to-point using TCP and secured using TLS.
• Support for Lagrange interpolation over finite fields.

How to run

Configuration

To run one node of the protocol, you need to specify the network configuration for that node. The configuration is specified using a JSON file. The following example shows a basic configuration.

{
  "base_port": 5000,
  "timeout": 5000,
  "sleep_time": 500,
  "peer_ips": [
    "127.0.0.1",
    "127.0.0.1",
    "127.0.0.1"
  ],
  "server_cert": "./certs/server_cert_p0.crt",
  "priv_key": "./certs/priv_key_p0.pem",
  "trusted_certs": [
    "./certs/rootCA.crt"
  ]
}

The fields above are explained next:

• The base_port, is the port that will be used as a base to compute the actual port in which the party will be listening to. For a party with index i, the listening port is base_port + i.
• The timeout is the number of milliseconds a party will repeatedly try to connect with another party. If the timeout is reached, the application returns an error.
• The sleep_time is the number of milliseconds that a party will wait before trying to connect again with another party in case the connection is not successful.
• The peer_ips is the list of IPs for all the peers engaged in the protocol. In this case, the array is specified in such a way that the party with index i has IP peer_ips[i].
• The server_cert is the certificate path for that node for secure communication.
• The priv_key is the file with the private key associated with the certificate in server_cert. This private key is used for secure communication.
• trusted_certs is a list of paths with trusted CA certificates. This is useful in executions where the certificates are self-signed.

If you want to generate the certificates and private keys for a local execution you can execute the following command:

bash gen_self_signed_certs.sh <n_parties>

Usage

First, you need to load the configuration for the node using the NetworkConfig struct. To create a network configuration, you provide the path of the JSON configuration file to the constructor function of the NetworkConfig instance. Once the network configuration is loaded, you create a Network instance that contains the streams to the peers.

The streams for communication send Packet instances, which is an encapsulation of bytes. As an example, the packets may contain information of shares, field elements, polynomials, or any other serializable type in the library. Theinteraction between parties are done using the functions send and recv defined in the Network implementation.