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现在我来分析一下这个DodeKing的源码。主要两个合约BABYTOKEN，BABYTOKENDividendTrackerBABYTOKEN我们来分析下它的构造函数 name_ 合约代币名称，symbol_合约代币符号，totalSupply_合约代币总量，addrs数组存放四个地址，地址1：要奖励的代币合约地址，地址2：swap路由，地址3：market钱包，地址4：分发分红合约地址，feeSettings数组存放3个参数，参数1：分红比，

VulnerabilityIf an address is a contract then the size of code stored at the address will be greater than 0 right?Let's see how we can create a contract with code size returned byextcodesizeequal to 0.// SPDX-License-Identifier: MITpragma solidit..

Signing messages off-chain and having a contract that requires that signature before executing a function is a useful technique.For example this technique is used to:reduce number of transaction on chain gas-less transaction, calledmeta transactionV.

Vulnerabilityblock.timestampcan be manipulated by miners with the following constraintsit cannot be stamped with an earlier time than its parent it cannot be too far in the future// SPDX-License-Identifier: MITpragma solidity ^0.8.10;/*Roulette.

VulnerabilityTransactions take some time before they are mined. An attacker can watch the transaction pool and send a transaction, have it included in a block before the original transaction. This mechanism can be abused to re-order transactions to the a

A honeypot is a trap to catch hackers.VulnerabilityCombining two exploits, reentrancy and hiding malicious code, we can build a contractthat will catch malicious users.// SPDX-License-Identifier: MITpragma solidity ^0.8.10;/*Bank is a contract

What's the difference betweenmsg.senderandtx.origin?If contract A calls B, and B calls C, in Cmsg.senderis B andtx.originis A.VulnerabilityA malicious contract can deceive the owner of a contract into calling a function that only the owner sho...

VulnerabilityThere are many ways to attack a smart contract to make it unusable.One exploit we introduce here is denial of service by making the function to send Ether fail.// SPDX-License-Identifier: MITpragma solidity ^0.8.10;/*The goal of Kin

Vulnerabilitydelegatecallis tricky to use and wrong usage or incorrect understanding can lead to devastating results.You must keep 2 things in mind when usingdelegatecalldelegatecallpreserves context (storage, caller, etc...) storage layout must ...

VulnerabilityAll data on a smart contract can be read.Let's see how we can readprivatedata. In the process you will learn how Solidity stores state variables.// SPDX-License-Identifier: MITpragma solidity ^0.8.10;/*Note: cannot use web3 on JVM..

Contracts can be deleted from the blockchain by callingselfdestruct.selfdestructsends all remaining Ether stored in the contract to a designated address.VulnerabilityA malicious contract can useselfdestructto force sending Ether to any contract....

VulnerabilitySolidity < 0.8Integers in Solidity overflow / underflow without any errorsSolidity >= 0.8Default behaviour of Solidity 0.8 for overflow / underflow is to throw an error.// SPDX-License-Identifier: MITpragma solidity ^0.7.6;

Hacks Re-Entrancy

钱包APP先看截图区块浏览器浏览器地址http://120.53.106.253/#/EOS公链搭建一 .准备1. eosio账户公钥写死在代码中， 在代码根目录 CMakeList.txt里面，找到 EOSIO_ROOT_KEY，改为自己创建的公钥。并把新的密钥对 要在 config.ini文件中保存，见文件中 “signature-provider = 。。。”。 2.编译，安装，参加本人另一篇EOS编译文章...

准备Uniswap合约源码https://download.youkuaiyun.com/download/yanning1314/12890659核心合约周边合约前端代码在Uniswap的核心代码中,主要包含3个合约:工厂合约,配对合约,ERC20合约.其中配对合约继承了ERC20合约,我们可以把它们看作一个合约.工厂合约通过create2方法部署配对合约,所以在部署合约时只需要部署工厂合约.周边合约中包括一些示例代码,例如价格预言机,闪电交换,其中最重要的是路由合约.在周边合约的代码库中,包含两个路由合