sw3 contracts

Contracts for Swap, Swear and Swindle.

Please note that all contracts within this repository are considered highly experimental and may cause loss of funds if used in production.

The master branch only contains the SimpleSwap contract for now. Everything else (full Swap, Swear and Swindle) can be found in the experimental branch.

Tests

This is a hardhat project using the truffle plugin (for tests as this used to be truffle-based). You can run tests using yarn test.

yarn
yarn test

To also generate coverage information use yarn coverage instead.

Linting

This repo currently uses solhint as linter. It can be called through yarn:

yarn lint

Go-bindings

To generate go bindings use

yarn abigen

This will generate the bindings in the bindings/ directory. Suitable versions of solc and abigen have to be installed for this to work. Alternatively this can also be done through docker:

docker build -t sw3 -f Dockerfile.abigen .
docker run -v $(pwd)/bindings:/sw3/bindings sw3 yarn abigen

In addition to the file from abigen this will also generate a go file that includes the runtime bytecode.

The go bindings are automatically generated on every release git tag and the pushed to the ethersphere/go-sw3-abi repository.

Deployments

Swap is deployed on the following networks:

Test Deployments

Swap is deployed on the following testnets:

Overview

SimpleSwap

SimpleSwap is a chequebook-style contract with support hard deposits.

Cheques

The issuer can issue cheques. Those are a signed piece of data containing the swap address, a beneficiary, and a cumulative amount. If the beneficiary wishes to cash the cheque it needs to be sent to the contract using the cashChequeBeneficiary function. Alternatively anyone else can also cash the cheque using cashCheque provided they have a signature from the beneficiary. In that case they might also get a portion of the payout as a fee. If there is not enough liquid balance in the contract part of the cheque might bounce (whether the full cheque was paid out should be verified through the ChequeCashed event). Later the beneficiary can try cashing again to get the remaining amount.

Hard Deposit

The issuer can lock a certain amount of the balance to a specific beneficiary (increaseHardDeposit) to give solvency guarantees up to the amount of the hard deposit. Decreasing a hard deposit is a two step process: First it needs to be prepared (prepareDecreaseHardDeposit) to start a security delay, which the beneficiary can use to cash the outstanding cheques. Afterwards the deposit can be decreased (decreaseHardDeposit). The balance not covered by hard deposits can be withdrawn by the issuer at any time.

Data Formats

Signatures

For signing purposes the chequebook uses EIP-712 Ethereum typed structured data hashing and signing. The EIP712Domain domain name is Chequebook in version 1.0. The chainId field is used, the verifyingContract and salt fields are omitted.

Cheques

CashOut

CustomHardDepositDecreaseTimeout

Factory

SimpleSwap has an accompanying factory contract SimpleSwapFactory. Deploying through the factory guarantees that the SimpleSwap contract was deployed with the correct init code.

Swap

Swap is SimpleSwap extended with support for promissory notes. You can find it in the experimental branch.

Swear and Swindle

Swear and Swindle are the contracts for the trial system of sw3. You can find them in the experimental branch.

Releasing

To release a new stable version, tag the commit without the -rcX suffix. For example, to release v0.4.0, execute the following command: git tag v0.4.0 && git push origin v0.4.0. This will generate Golang source code for the smart contracts and publish it to the ethersphere/go-sw3-abi/ repository.