69 lines
1.7 KiB
Solidity
69 lines
1.7 KiB
Solidity
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/*
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* @article: https://blog.positive.com/predicting-random-numbers-in-ethereum-smart-contracts-e5358c6b8620
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* @source: https://etherscan.io/address/0x80ddae5251047d6ceb29765f38fed1c0013004b7#code
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* @vulnerable_at_lines: 38,42
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* @author: -
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*/
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//added pragma version
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pragma solidity ^0.4.0;
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contract Lottery {
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event GetBet(uint betAmount, uint blockNumber, bool won);
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struct Bet {
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uint betAmount;
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uint blockNumber;
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bool won;
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}
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address private organizer;
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Bet[] private bets;
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// Create a new lottery with numOfBets supported bets.
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function Lottery() {
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organizer = msg.sender;
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}
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// Fallback function returns ether
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function() {
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throw;
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}
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// Make a bet
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function makeBet() {
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// Won if block number is even
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// (note: this is a terrible source of randomness, please don't use this with real money)
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// <yes> <report> BAD_RANDOMNESS
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bool won = (block.number % 2) == 0;
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// Record the bet with an event
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// <yes> <report> BAD_RANDOMNESS
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bets.push(Bet(msg.value, block.number, won));
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// Payout if the user won, otherwise take their money
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if(won) {
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if(!msg.sender.send(msg.value)) {
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// Return ether to sender
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throw;
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}
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}
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}
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// Get all bets that have been made
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function getBets() {
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if(msg.sender != organizer) { throw; }
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for (uint i = 0; i < bets.length; i++) {
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GetBet(bets[i].betAmount, bets[i].blockNumber, bets[i].won);
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}
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}
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// Suicide :(
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function destroy() {
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if(msg.sender != organizer) { throw; }
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suicide(organizer);
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}
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}
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