socket-ll-contracts

The smart contracts that power the liquidity Layer of Socket. Socket-ll will abstract the bridges and facilitate the cross-chain bridge and swap

Architecture

• Socket smart contracts are aggregators of DEXs, DEX aggregators & bridges. The key highlight of Socket’s smart contract architecture is that we choose modularity over upgradability. Once a module is deployed it can only be disabled by the owner, everything is immutable.

• Users interact with Socket’s Socketgateway.sol contract to initiate a bridging, swap or other complex interactions.

• This contract delegates to modules called routes. These are deployed as different contracts and tracked using routeIds.

• Bridge and Swap routes have logic for interacting with bridges and dexes.

• Controller routes have other flows apart from direct bridge/dex interactions.

• Initial set of 512 routes get predetermined and get hardcoded in SocketGateway for gas savings.

• These are deployed using SocketDeployFactory.

• SocketDeployFactory is also able to destroy these and deploy a disabled contract in place of original route.

• More routes can be added directly to SocketGateway via normal deployment and can be disabled by setting their address to 0.

• In both forms, routes can be added against a routeId only once. After this the routeId can only be disabled if needed.

• The system allows for routeId based whitelisting to be configured by integrators to achieve their desired security.

Security Assumptions

• The contracts are build for routing funds over existing bridge/dex contracts.

• The contracts are not supposed to hold any funds post tx execution.

• An exception to this is the feesTakerAddress supplied to FeesTakerController.

• Factory, create2 and selfdestruct based approach is used to predetermine a set of contracts which can be hardcoded on Gateway.

• Another approach to store and use contract addresses from the storage of Gateway contract is also in place.

• We fallback to this approach when selfdestruct is deprecated. All of the routes controlled by Factory will be destroyed and disabled at when this happens.

Bridge

Swap

Controller

Local Development

Prereqs

• Foundry
• typescript
• Yarn
• hardhat

environment

• create .env file under root directory
• refer to .env.example file for all keys in .env

Setup

Clone project and install dependencies.

# clone the repository
git clone https://github.com/SocketDotTech/socket-ll-contracts

# move to repository folder
cd socket-ll-contracts

# install node modules
yarn install

# install forge dependencies
forge install

Submodules

Submodules imported:

• solmate (for contracts)
• openzeppelin-contracts
• forge-std (for testing)

Versions of dependencies can be checked with git submodule status.

Foundry dependency verification

• Essential dependencies foundry library are:

1. forge-std
2. solmate
3. openzeppelin-contracts
4. ds-test

• These dependency config is added to remappings.txt under root directory

• If you would like to manually install the dependencies, then use commands:

forge install transmissions11/solmate

forge install Openzeppelin/openzeppelin-contracts

forge install forge-std

forge install ds-test

Project Layout

├── lib
│   └── ds-test - forge dependencies installed as git submodules
│   └── forge-std - forge dependencies installed as git submodules
│   └── openzeppelin-contracts - forge dependencies installed as git submodules
│   └── solmate - forge dependencies installed as git submodules
|
├── src
│     └── bridges - all bridge implementation contracts
│     └── controllers - all controller implementation contracts
│     └── deployFactory - Contracts to control code at predetermined route addresses
│     └── errors - errors used in reverts
│     └── interfaces - interface contracts with requests for bridges, swaps and controllers
│     └── libraries - libraries used for byte operations
│     └── static - static data used in contracts
│     └── swap - all swap implementation contracts
│     └── utils - Helper utils used in other contracts
|
└── test
|   └── solidity
|       └── bridges - tests for bridge routes
|       └── controllers - tests for controller contracts
|       └── ownership - tests for ownership management of contracts
|       └── rescue-funds - tests for rescue-fund functions
|       └── routes - tests for route management functions
|       └── swap - tests for swap routes
|       └── swap-bridge - tests for swap-and-bridge function
|       └── SokcetGatewayBaseTest.sol - Base contract inherited by all tests
|
└── Files for project setup

Lint

Linter is run automatically before each commit. It can also be triggered manually using yarn lint script.

yarn lint

Test

Tests are run using the Forge tool of Foundry.

forge test

IDE Setup

It is recommended to setup the ide to work with solidity development. In case of VSCode, Solidity and Prettier plugins should work best when configured using following settings -

{
    "solidity.compileUsingRemoteVersion": "v0.8.15+commit.e14f2714",
    "solidity.packageDefaultDependenciesContractsDirectory": "src",
    "solidity.packageDefaultDependenciesDirectory": "lib",
    "editor.formatOnSave": true,
    "[solidity]": {
        "editor.tabSize": 4,
        "editor.defaultFormatter": "esbenp.prettier-vscode"
    },
    "solidity.remappings": [
        "forge-std/=lib/forge-std/src/",
        "ds-test/=lib/ds-test/src/",
        "solmate/=lib/solmate/src/",
        "openzeppelin-contracts/=lib/openzeppelin-contracts/src/"
    ],
}