timezone |
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Asia/Taipei |
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自我介绍
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你认为你会完成本次残酷学习吗?
學習內容:
- A 系列的 Ethernaut CTF, 之前做了差不多了. POC: ethernaut-foundry-solutions
- A 系列的 QuillAudit CTF 題目的網站關掉了, 幫大家收集了題目, 不過還是有幾題沒找到. 有找到題目的人可以在發出來.
- A 系列的 DamnVulnerableDeFi 有持續更新, 題目也不錯. Damn Vulnerable DeFi.
- 使用 Foundry 在本地解題目, 可以參考下面 RoadClosed 為例子
forge test --match-teat testRoadClosedExploit -vvvv
function addToWhitelist(address addr) public {
require(!isContract(addr), "Contracts are not allowed");
whitelistedMinters[addr] = true;
}
function changeOwner(address addr) public {
require(whitelistedMinters[addr], "You are not whitelisted");
require(msg.sender == addr, "address must be msg.sender");
require(addr != address(0), "Zero address");
owner = addr;
}
function pwn(address addr) external payable {
require(!isContract(msg.sender), "Contracts are not allowed");
require(msg.sender == addr, "address must be msg.sender");
require(msg.sender == owner, "Must be owner");
hacked = true;
}
function pwn() external payable {
require(msg.sender == pwner);
hacked = true;
}
- 解決這個題目需要成為合約的 owner 和 hacked = true.
- On-chain: 可以透過
cast send
或是 forge script 來解. - Local: 透過 forge test 通常是在local解題, 方便 debug.
- RoadClosed 為例子我寫了2個解題方式. testRoadClosedExploit 和 testRoadClosedContractExploit (因為題目有檢查msg.sender是不是合約, 所以可以透過constructor來繞過 isContract)
- POC