33 lines
1.1 KiB
Solidity
33 lines
1.1 KiB
Solidity
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// SPDX-License-Identifier: MIT
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pragma solidity ^0.8.0;
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contract PolkadotCTF {
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address public winner;
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event FlagCaptured(address indexed player);
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// Encoded parts of the flag as byte arrays
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bytes private part1 = hex"50437b497354686973";
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bytes private part2 = hex"546865466c61674f72";
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bytes private part3 = hex"644e6f747d";
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// Function to decode the parts and get the full flag
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function decodeFlag() public view returns (string memory) {
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return string(abi.encodePacked(part1, part2, part3));
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}
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// Function to capture the flag
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function captureFlag(string memory _solution) public {
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string memory decodedFlag = decodeFlag();
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require(keccak256(abi.encodePacked(_solution)) == keccak256(abi.encodePacked(decodedFlag)), "Incorrect solution");
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winner = msg.sender;
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emit FlagCaptured(msg.sender);
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}
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// Function to get the flag
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function getFlag() public view returns (string memory) {
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require(msg.sender == winner, "You are not the winner");
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return decodeFlag();
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}
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}
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