gabes 0.1.5

Introduction

Garbled Circuits allow two distrusting parties to compute a joint function while keeping their inputs private. More precisely, it allows Alice with input x and Bob with input y to compute a function f(x, y) without Alice ever knowing y and without Bob knowing x. The way it does so is by first translating f to a boolean circuit from which it will cleverly obfuscate or garble the circuit to allow the computation of f while keeping the inputs private.

The classical example is that of two millionaires who wish to find out who is richer without revealing their wealth. In that case, f becomes the “>” (greater than) function, and x and y are their wealth.

Gabes implements garbled circuits in Python. The application runs as a command line interface but the functions required to run garbled circuits can be used without the command line (see gabes).

Installation

At the command line either via pip:

$ pip install gabes

Or, if you have virtualenvwrapper installed:

$ mkvirtualenv gabes
$ pip install gabes

Usage

Each party will run their own instance of the program on their computer as a CLI app. The garbler will provide the IP and port number to establish the connection with the evaluator.

Garbler’s Side:

gabes -g -grr3 -c Desktop/my-circuit.circuit -a localhost:5000

Evaluator’s Side:

gabes -e -grr3 -a localhost:5000

Flags

usage: gabes [-h] [-g] [-e] [-b bits] [-i identifier [identifier ...]]
                   [-c file] -a ip:port [-cl] [-pp] [-grr3] [-free] [-grr2]
                   [-fle] [-half]

Program to garble and evaluate a circuit.

optional arguments:
  -h, --help            show this help message and exit
  -g, --garbler         Set this flag to become the garbler
  -e, --evaluator       Set this flag to become the evaluator
  -b bits, --bits bits  Include your private input bitstring to the circuit
                        (e.g. 001011)
  -i identifier [identifier ...], --identifiers identifier [identifier ...]
                        Indicate which input wires you supply to the circuit
                        (e.g. -i A C D)
  -c file, --circuit file
                        Path of the file representing the circuit. Only the
                        garbler needs to supply the file
  -a ip:port, --address ip:port
                        IP address followed by the port number
  -cl, --classical      Set this flag for classical garbled circuits
  -pp, --point-and-permute
                        Set this flag to include point-and-permute
  -grr3, --grr3         Set this flag for GRR3 garbled circuits
  -free, --free-xor     Set this flag for free-xor garbled circuits
  -fle, --flexor        Set this flag for flexor garbled circuits
  -half, --half-gates   Set this flag for half gates garbled circuits

Documentation

All the documentation can be found in https://gabes.readthedocs.io/en/latest/