手机端开发网站模板下载,中企动力科技股份官网,ueditor转wordpress,中国建设规划采购网站ERC4626简介
ERC4626 协议是一种用于代币化保险库的标准。
我们经常说 DeFi 是货币乐高#xff0c;可以通过组合多个协议来创造新的协议#xff1b; ERC4626 扩展了 ERC20 代币标准#xff0c;旨在推动收益金库的标准化#xff0c;它是 DeFi 乐高中的基础#xff0c;它允…ERC4626简介
ERC4626 协议是一种用于代币化保险库的标准。
我们经常说 DeFi 是货币乐高可以通过组合多个协议来创造新的协议 ERC4626 扩展了 ERC20 代币标准旨在推动收益金库的标准化它是 DeFi 乐高中的基础它允许你把底层资产质押到金库合约中从而获取一定比例的金库代币你存入的底层资产存储在金库中的这段时间会产生一定的收益——例如被用于借贷平台、收益聚合、流动资金池等你可以在任何时间拿着金库代币赎回本金以及一定收益。 ERC4626 主要逻辑
ERC4626 继承了 ERC20金库代币就是用 ERC20 代币代表的底层资产比如 WETH可以是任何有价值的代币提前存入金库
用户将特定的 ERC20 底层资产存进金库金库会给他铸造特定数量的金库代币相关函数为 deposit() 和 mint()。deposit(uint assets, address receiver) 函数让用户存入 assets 数量的资产并铸造相应数量的金库代币给 receiver 地址。mint(uint shares, address receiver) 与它类似只不过是以将铸造的金库代币数量作为参数
当用户从金库中提取底层资产时会销毁相应数量的金库代币。相关函数为 withdraw() 和 redeem()前者以取出底层资产数量为参数后者以销毁的金库代币数量为参数。 接口中定义
asset(): 返回金库的底层资产代币地址。totalAssets(): 返回金库中管理的底层资产总额。convertToShares(): 返回利用一定数量底层资产可以换取的金库代币。convertToAssets(): 返回利用一定数量金库代币可以换取的底层资产。 deposit(): 存款向金库存入 assets 数量的底层资产然后增发相应比例的shares 金库代币给 receiver 。触发 Deposit 事件。maxDeposit(): 返回单次存款可存的最大底层资产数额。
previewDeposit(): 在当前链上环境模拟存款一定数额的底层资产能够获得的金库代币。 mint(): 铸造指定想获得的 shares 数量的金库代币计算出需要存入的 assets 数量的底层资产金库从用户账户转出 assets 数量的底层资产再给 receiver 铸造相应数量的金库代币。触发 Deposit 事件。maxMint(): 返回单次可以铸造的最大金库代币额度。
previewMint(): 用于用户在当前链上环境模拟铸造一定数额的金库额度需要存款的基础资产数量。 withdraw(): 提款金库将assets数量的底层资产发送给 receiver owner 销毁相应数量的金库代币。触发 Withdraw 事件。maxWithdraw(): 返回某个用户地址单次取款可以提取的最大基础资产额度。
previewWithdraw(): 当前链上环境模拟提款一定数量的底层资产需要的金库代币数量。
redeem(): 赎回owner 销毁shares 数量的金库代币然后金库将相应数量的底层资产发给 receiver触发 Withdraw 事件。maxRedeem(): 返回单次赎回可以销毁的最大金库代币。previewRedeem(): 在当前链上环境模拟销毁制定数量的金库代币能够赎回的底层资产数量。
IERC4626 接口合约共包含 2 个事件:
Deposit : 存款时触发事件。Withdraw : 取款时触发事件。
代码分析
这里直接使用openzeppelin库的源码 abstract contract ERC4626 is ERC20, IERC4626 {using Math for uint256;IERC20 private immutable _asset; //底层资产地址uint8 private immutable _decimals; //shares的decimal//初始化constructor(IERC20 asset_) {(bool success, uint8 assetDecimals) _tryGetAssetDecimals(asset_);_decimals success ? assetDecimals : super.decimals();_asset asset_;}//获取底层资产decimalfunction _tryGetAssetDecimals(IERC20 asset_) private view returns (bool, uint8) {//使用底层资产地址通过staticcall获取decimal(bool success, bytes memory encodedDecimals) address(asset_).staticcall(abi.encodeWithSelector(IERC20Metadata.decimals.selector));//返回成功且有数据就判断数据是否255,满足就返回该值if (success encodedDecimals.length 32) {uint256 returnedDecimals abi.decode(encodedDecimals, (uint256));if (returnedDecimals type(uint8).max) {return (true, uint8(returnedDecimals));}}return (false, 0);}//获取金库代币的decimal注意这是对ERC20中函数的重写function decimals() public view virtual override(IERC20Metadata, ERC20) returns (uint8) {return _decimals;}//底层资产地址function asset() public view virtual override returns (address) {return address(_asset);}//金库中底层资产的数量function totalAssets() public view virtual override returns (uint256) {return _asset.balanceOf(address(this));}//指定数量的底层资产可换取金库代币的数量function convertToShares(uint256 assets) public view virtual override returns (uint256 shares) {return _convertToShares(assets, Math.Rounding.Down);}//指定数量的金库代币可换取底层资产的数量function convertToAssets(uint256 shares) public view virtual override returns (uint256 assets) {return _convertToAssets(shares, Math.Rounding.Down);}//如何金库底层资产数量0 || 金库代币0则返回2^256-1 否则为0function maxDeposit(address) public view virtual override returns (uint256) {return _isVaultCollateralized() ? type(uint256).max : 0;}//单次最大铸造金库代币返回2^256-1 function maxMint(address) public view virtual override returns (uint256) {return type(uint256).max;}//返回owner账户下金库代币可以兑换出来的底层资产数量 function maxWithdraw(address owner) public view virtual override returns (uint256) {return _convertToAssets(balanceOf(owner), Math.Rounding.Down);}//返回owner账户下金库代币数量function maxRedeem(address owner) public view virtual override returns (uint256) {return balanceOf(owner);}//计算此时存入指定数量的底层资产可以铸造多少金库代币实际金库代币要低于理论值function previewDeposit(uint256 assets) public view virtual override returns (uint256) {return _convertToShares(assets, Math.Rounding.Down);}//计算此时要铸造指定数量的金库代币可以质押的底层资产数量实际质押的底层资产数量要高于理论值function previewMint(uint256 shares) public view virtual override returns (uint256) {return _convertToAssets(shares, Math.Rounding.Up);}//计算此时赎回指定数量的底层资产需要多少金库代币实际金库代币要高于理论值function previewWithdraw(uint256 assets) public view virtual override returns (uint256) {return _convertToShares(assets, Math.Rounding.Up);}//计算此时指定数量的金库代币可以赎回的底层资产数量实际兑换的底层资产数量要小于理论值function previewRedeem(uint256 shares) public view virtual override returns (uint256) {return _convertToAssets(shares, Math.Rounding.Down);}//存入指定数量的底层资产并为receiver铸造相应的金库代币function deposit(uint256 assets, address receiver) public virtual override returns (uint256) {//校验参数质押的底层资产数量不可大于receiver能质押的最大值require(assets maxDeposit(receiver), ERC4626: deposit more than max);//计算可获取金库代币数量uint256 shares previewDeposit(assets);//用户向金库质押assets数量的底层资产为receiver增发shares数量的金库代币_deposit(_msgSender(), receiver, assets, shares);return shares;}//要铸造指定数量的金库代币并扣除相应的底层资产function mint(uint256 shares, address receiver) public virtual override returns (uint256) {//校验参数require(shares maxMint(receiver), ERC4626: mint more than max);//计算增发shares数量的代币金库需要多少底层资产uint256 assets previewMint(shares);//用户向金库质押assets数量的底层资产为receiver增发shares数量的金库代币_deposit(_msgSender(), receiver, assets, shares);return assets;}//赎回指定数量的底层资产并扣除相应的金库代币function withdraw(uint256 assets,address receiver,address owner) public virtual override returns (uint256) {require(assets maxWithdraw(owner), ERC4626: withdraw more than max);//计算赎回指定的底层资产需要的金库代币数量uint256 shares previewWithdraw(assets);//销毁owner名下shares数量的金库代币给receiver转入assets数量的底层资产_withdraw(_msgSender(), receiver, owner, assets, shares);return shares;}//销毁指定数量的金库代币获取想要数量的底层资产function redeem(uint256 shares,address receiver,address owner) public virtual override returns (uint256) {require(shares maxRedeem(owner), ERC4626: redeem more than max);//计算指定数量的金库代币可以赎回底层资产的数量uint256 assets previewRedeem(shares);//销毁owner名下shares数量的金库代币给receiver转入assets数量的底层资产_withdraw(_msgSender(), receiver, owner, assets, shares);return assets;}//计算此时指定数量的底层资产返回可以铸造多少金库代币function _convertToShares(uint256 assets, Math.Rounding rounding) internal view virtual returns (uint256 shares) {uint256 supply totalSupply();return(assets 0 || supply 0)? _initialConvertToShares(assets, rounding): assets.mulDiv(supply, totalAssets(), rounding);//返回assets * 金库代币总量 /底层资产总量}//金库代币总量为0时或者底层资产为0金库代币增发数量function _initialConvertToShares(uint256 assets,Math.Rounding /*rounding*/) internal view virtual returns (uint256 shares) {return assets;//默认1:1}//计算此时指定数量的金库代币返回可以兑换的底层资产数量function _convertToAssets(uint256 shares, Math.Rounding rounding) internal view virtual returns (uint256 assets) {uint256 supply totalSupply();return(supply 0) ? _initialConvertToAssets(shares, rounding) : shares.mulDiv(totalAssets(), supply, rounding);//返回shares* 底层资产总量 /金库代币总量}//金库代币总量为0时可兑换底层资产的数量function _initialConvertToAssets(uint256 shares,Math.Rounding /*rounding*/) internal view virtual returns (uint256 assets) {return shares; //默认1:1}//caller向金库质押assets数量的底层资产为receiver增发shares数量的金库代币function _deposit(address caller,address receiver,uint256 assets,uint256 shares) internal virtual {//使用safeerc20的safetransferfrom方法进行底层资产的转账SafeERC20.safeTransferFrom(_asset, caller, address(this), assets);//增发金库代币_mint(receiver, shares);emit Deposit(caller, receiver, assets, shares);}//销毁owner名下shares数量的金库代币给receiver转入assets数量的底层资产function _withdraw(address caller,address receiver,address owner,uint256 assets,uint256 shares) internal virtual {if (caller ! owner) {_spendAllowance(owner, caller, shares);}//销毁金库代币_burn(owner, shares);//使用safeerc20的safetransfer方法进行底层资产的转账SafeERC20.safeTransfer(_asset, receiver, assets);emit Withdraw(caller, receiver, owner, assets, shares);}//检测金库是否还有底层资产 || 金库代币0这两种情况都认为是正常 function _isVaultCollateralized() private view returns (bool) {return totalAssets() 0 || totalSupply() 0;}
}
测试
测试使用foundry可以直接看-----github代码就不做过多分析了
