Verex

Overview

Verex is a tool to deploy solidity smart-contracts generated with the formal verification Stainless library to the Byzcoin ledger.

Installation

$ git clone https://github.com/dedis/student_18_hugo_verex
//...
$ cd student_18_hugo_verex/byzcoin

From Stainless..

Install Smart which is the current solidity interpreter of the LARA laboratory.

$ git clone https://github.com/epfl-lara/smart.git
Cloning into 'smart'...
// ...
$ cd smart
$ sbt clean universal:stage

You can then create a symbolic link (e.g. for Linux & Mac OS-X) to have access to a stainless command-line.

 ln -s frontends/scalac/target/universal/stage/bin/stainless-scalac stainless

Once the setup is done, you can now create a new smart contract using the Candy contract as a template.

If you wish to use one of the existing contracts, you can define a constructor with the desired parameters directly with Scala.

Stainless is able to verify that the assertions written in the contract are indeed valid :

./stainless *.scala or adding the --strict-arithmetic flag to verify overflows issues.

For more details on formal verification refer of course to the Stainless and Smart repositories.

..to Solidity

Copy your Scala code into a new folder with the contract name into the contracts folder.

Run

./stainless *.scala --solidity

which will produce a new solidity file with your contract name.

Install a Solidity compiler.

Run

solcjs *.sol --bin
solcjs *.sol --abi

Which will generate a ContractName_sol_ContractName.bin and ContractName_sol_ContractName.abi file containing the bytecode and the ABI of the smart contract.

.. to Byzcoin

you can now test your contract deployment on the Byzcoin ledger by refering to the bvmContract_test.go and to the detailed README.md of the Byzcoin Virtual Machine.

Acknowledgments

Project was made in conjunction with DEDIS and LARA laboratories at EPFL.

hugoroussel / student_18_hugo_verex