SAUCy

This is an imlementation of the basic UC framework. It provides code to specify functionalities, protocols, and adversaries, and provides an execution environment to run real and ideal word executions.

Installation

Installation is easy (we assume python>=3.5)

• Clone the repo and go into the uc_contracts/ directory.
• Install the dependencies with pip install -r uc/requirements.txt
• Install the the uc module as a working module with pip install -e .

Docker

We include a simple Dockerfile based on python3.6, you can see there are not many dependencies

    docker build -t saucy .
    docker run -v $PWD:/uc-contracts -it saucy

If you're able to run python uc/apps/coinflip/env.py successfully and get output you're good to go!

• uc/: Python UC module that implements the basic framework
  • itm.py: implements the ITM
  • protocol.py: the base class for all protocols and the ProtocolWrapper and the DummyParty
  • functionality.py: the base class for all functionalities
  • adversary.py: the base for all adversaries and the DummyAdversary
  • execuc.py: executes a UC experiment given an environment, functionality, protocol, and adversary
  • compose.py: a composition operator for protocols and simulators
  • utils.py: some handy functions
• uc/apps/: Examples of using the Python UC module
  • commitment/: an example of a bit commitment in the random oracle model
  • coinflip/: a coin flip that uses bit commitment
  • simplecomp/: composition example, deplaces F_com with commitment protocol

Things unique from the UC framework

We use a construct called the ProtocolWrapper in protocol.py. This wrapper encapsulates the "protocol" and internaly creates instances of the protocol as protocol parties. It also routes messages to/from the protocol parties based on the intended pid recipient of the messages that it receives. Protocols in UC are usually not in any kind of wrapper and therefore, from their point of view, are communicating over a channel directly to the functionality or the environment. Therefore, the ProtocolWrapper ensures this is the view of the parties. A consequence of the wrapper is that the functionality, adversary, and environment need to know the pid of the messages received by the wrapper. The parties themselves don't add their pid to messages because they "think" they are directly communicating to other with a dedicated channel. Therefore, the wrapper appends the pid of the sending parties to all outgoing messages by them. See the docstring for the ProtocolWrapper for a more in depth explanation.