Venus Protocol

The Venus Protocol is an Binance Smart Chain smart contract for supplying or borrowing assets. Through the vToken contracts, accounts on the blockchain supply capital (BNB or BEP-20 tokens) to receive vTokens or borrow assets from the protocol (holding other assets as collateral). The protocol will also enable the minting of VAI, which is the first synthetic stablecoin on Venus that aims to be pegged to 1 USD. VAI is minted by the same collateral that is supplied to the protocol. The Venus vToken contracts track these balances and algorithmically set interest rates for borrowers.

Before getting started with this repo, please read:

Contracts

We detail a few of the core contracts in the Venus protocol.

VToken, VBep20 and VBNB

The Venus vTokens, which are self-contained borrowing and lending contracts. VToken contains the core logic and VBep20, VBUSD, VSXP and VBNB add public interfaces for Bep20 tokens and bnb, respectively. Each VToken is assigned an interest rate and risk model (see InterestRateModel and Comptroller sections), and allows accounts to *mint* (supply capital), *redeem* (withdraw capital), *borrow* and *repay a borrow*. Each VToken is an BEP-20 compliant token where balances represent ownership of the market.

Comptroller

The risk model contract, which validates permissible user actions and disallows actions if they do not fit certain risk parameters. For instance, the Comptroller enforces that each borrowing user must maintain a sufficient collateral balance across all vTokens.

XVS

The Venus Governance Token (XVS). Holders of this token have the ability to govern the protocol via the governor contract.

SXP

The Venus Governance Token (SXP). Holders of this token have the ability to govern the protocol via the governor contract.

Governor Alpha

The administrator of the Venus timelock contract. Holders of XVS(SXP) token may create and vote on proposals which will be queued into the Venus timelock and then have effects on Venus vToken and Comptroller contracts. This contract may be replaced in the future with a beta version.

InterestRateModel

Contracts which define interest rate models. These models algorithmically determine interest rates based on the current utilization of a given market (that is, how much of the supplied assets are liquid versus borrowed).

Careful Math

Library for safe math operations.

ErrorReporter

Library for tracking error codes and failure conditions.

Exponential

Library for handling fixed-point decimal numbers.

SafeToken

Library for safely handling Bep20 interaction.

WhitePaperInterestRateModel

Initial interest rate model, as defined in the Whitepaper. This contract accepts a base rate and slope parameter in its constructor.

Installation

To run venus, pull the repository from GitHub and install its dependencies. You will need yarn or npm installed.

git clone https://github.com/SwipeWallet/venus-protocol
cd venus-protocol
yarn install --lock-file # or `npm install`

REPL

The Venus Protocol has a simple scenario evaluation tool to test and evaluate scenarios which could occur on the blockchain. This is primarily used for constructing high-level integration tests. The tool also has a REPL to interact with local the Venus Protocol (similar to truffle console).

yarn repl -n development
yarn repl -n rinkeby

> Read VToken vBAT Address
Command: Read VToken vBAT Address
AddressV<val=0xAD53863b864AE703D31b819d29c14cDA93D7c6a6>

You can read more about the scenario runner in the Scenario Docs on steps for using the repl.

Testing

Jest contract tests are defined under the tests directory. To run the tests run:

yarn test

Integration Specs

There are additional tests under the spec/scenario folder. These are high-level integration tests based on the scenario runner depicted above. The aim of these tests is to be highly literate and have high coverage in the interaction of contracts.

Formal Verification Specs

The Venus Protocol has a number of formal verification specifications, powered by Certik. The Certik Verification evaluates smart contracts for vulnerabilities and certifies their behavior with respect to a custom function specification.

See the Scenario Docs on steps for using the repl.

Testing

Contract tests are defined under the tests directory. To run the tests run:

yarn test

Code Coverage

To run code coverage, run:

yarn coverage

Linting

To lint the code, run:

yarn lint

Docker

To run in docker:

# Build the docker image
docker build -t swipewallet/venus-protocol .

# Run a shell to the built image
docker run -it swipewallet/venus-protocol /bin/sh

From within a docker shell, you can interact locally with the protocol via ganache and truffle:

    /venus-protocol > yarn console -n goerli
    Using network goerli https://goerli-eth.venus.io
    Saddle console on network goerli https://goerli-eth.venus.io
    Deployed goerli contracts
      comptroller: 0x627EA49279FD0dE89186A58b8758aD02B6Be2867
      xvs: 0xfa5E1B628EFB17C024ca76f65B45Faf6B3128CA5
      sxp: 0xfa5E1B628EFB17C024ca76f65B45Faf6B3128CA5
      governorAlpha: 0x8C3969Dd514B559D78135e9C210F2F773Feadf21
      maximillion: 0x73d3F01b8aC5063f4601C7C45DA5Fdf1b5240C92
      priceOracle: 0x9A536Ed5C97686988F93C9f7C2A390bF3B59c0ec
      priceOracleProxy: 0xd0c84453b3945cd7e84BF7fc53BfFd6718913B71
      timelock: 0x25e46957363e16C4e2D5F2854b062475F9f8d287
      unitroller: 0x627EA49279FD0dE89186A58b8758aD02B6Be2867

    > await xvs.methods.totalSupply().call()
    '300000000000000000000000000'
    > await sxp.methods.totalSupply().call()
    '28971492600000000000000000'

Console

After you deploy, as above, you can run a truffle console with the following command:

yarn console -n goerli

This command will start a saddle console conencted to Goerli testnet (see Saddle README):

    Using network goerli https://goerli.infura.io/v3/e1a5d4d2c06a4e81945fca56d0d5d8ea
    Saddle console on network goerli https://goerli.infura.io/v3/e1a5d4d2c06a4e81945fca56d0d5d8ea
    Deployed goerli contracts
      comptroller: 0x627EA49279FD0dE89186A58b8758aD02B6Be2867
      xvs: 0xfa5E1B628EFB17C024ca76f65B45Faf6B3128CA5
      sxp: 0xfa5E1B628EFB17C024ca76f65B45Faf6B3128CA5
      governorAlpha: 0x8C3969Dd514B559D78135e9C210F2F773Feadf21
      maximillion: 0x73d3F01b8aC5063f4601C7C45DA5Fdf1b5240C92
      priceOracle: 0x9A536Ed5C97686988F93C9f7C2A390bF3B59c0ec
      priceOracleProxy: 0xd0c84453b3945cd7e84BF7fc53BfFd6718913B71
      timelock: 0x25e46957363e16C4e2D5F2854b062475F9f8d287
      unitroller: 0x627EA49279FD0dE89186A58b8758aD02B6Be2867

    > await xvs.methods.totalSupply().call()
    '300000000000000000000000000'
    > await sxp.methods.totalSupply().call()
    '28971492600000000000000000'

Deploying a VToken from Source

Note: you will need to set ~/.ethereum/<network> with your private key or assign your private key to the environment variable ACCOUNT.

Note: for all sections including BscScan verification, you must set the BSCSCAN_API_KEY to a valid API Key from BscScan.

To deploy a new vToken, you can run the token:deploy. command, as follows. If you set VERIFY=true, the script will verify the token on BscScan as well. The JSON here is the token config JSON, which should be specific to the token you wish to list.

npx saddle -n rinkeby script token:deploy '{
  "underlying": "0x577D296678535e4903D59A4C929B718e1D575e0A",
  "comptroller": "$Comptroller",
  "interestRateModel": "$Base200bps_Slope3000bps",
  "initialExchangeRateMantissa": "2.0e18",
  "name": "Venus Kyber Network Crystal",
  "symbol": "vKNC",
  "decimals": "8",
  "admin": "$Timelock"
}'

If you only want to verify an existing token an BscScan, make sure BSCSCAN_API_KEY is set and run token:verify with the first argument as the token address and the second as the token config JSON:

npx saddle -n rinkeby script token:verify 0x19B674715cD20626415C738400FDd0d32D6809B6 '{
  "underlying": "0x577D296678535e4903D59A4C929B718e1D575e0A",
  "comptroller": "$Comptroller",
  "interestRateModel": "$Base200bps_Slope3000bps",
  "initialExchangeRateMantissa": "2.0e18",
  "name": "Venus Kyber Network Crystal",
  "symbol": "vKNC",
  "decimals": "8",
  "admin": "$Timelock"
}'

Finally, to see if a given deployment matches this version of the Venus Protocol, you can run token:match with a token address and token config:

npx saddle -n rinkeby script token:match 0x19B674715cD20626415C738400FDd0d32D6809B6 '{
  "underlying": "0x577D296678535e4903D59A4C929B718e1D575e0A",
  "comptroller": "$Comptroller",
  "interestRateModel": "$Base200bps_Slope3000bps",
  "initialExchangeRateMantissa": "2.0e18",
  "name": "Venus Kyber Network Crystal",
  "symbol": "vKNC",
  "decimals": "8",
  "admin": "$Timelock"
}'

Deploying a VToken from Docker Build

---

To deploy a specific version of the Venus Protocol, you can use the token:deploy script through Docker:

docker run --env BSCSCAN_API_KEY --env VERIFY=true --env ACCOUNT=0x$(cat ~/.ethereum/rinkeby) SwipeWallet/venus-protocol:latest npx saddle -n rinkeby script token:deploy '{
  "underlying": "0x577D296678535e4903D59A4C929B718e1D575e0A",
  "comptroller": "$Comptroller",
  "interestRateModel": "$Base200bps_Slope3000bps",
  "initialExchangeRateMantissa": "2.0e18",
  "name": "Venus Kyber Network Crystal",
  "symbol": "vKNC",
  "decimals": "8",
  "admin": "$Timelock"
}'

To match a deployed contract against a given version of the Venus Protocol, you can run token:match through Docker, passing a token address and config:

docker run --env ACCOUNT=0x$(cat ~/.ethereum/rinkeby) SwipeWallet/venus-protocol:latest npx saddle -n rinkeby script token:match 0xF1BAd36CB247C82Cb4e9C2874374492Afb50d565 '{
  "underlying": "0x577D296678535e4903D59A4C929B718e1D575e0A",
  "comptroller": "$Comptroller",
  "interestRateModel": "$Base200bps_Slope3000bps",
  "initialExchangeRateMantissa": "2.0e18",
  "name": "Venus Kyber Network Crystal",
  "symbol": "vKNC",
  "decimals": "8",
  "admin": "$Timelock"
}'

Discussion

For any concerns with the protocol, open an issue or visit us on Telegram to discuss.

For security concerns, please email security@swipe.io.

_© Copyright 2020, Swipe Wallet