54 lines
1.0 KiB
Solidity
54 lines
1.0 KiB
Solidity
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/*
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* @source: http://blockchain.unica.it/projects/ethereum-survey/attacks.html#oddsandevens
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* @author: -
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* @vulnerable_at_lines: 25,28
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*/
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pragma solidity ^0.4.2;
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contract OddsAndEvens{
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struct Player {
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address addr;
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uint number;
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}
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Player[2] public players; //public only for debug purpose
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uint8 tot;
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address owner;
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function OddsAndEvens() {
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owner = msg.sender;
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}
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// <yes> <report> FRONT_RUNNING
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function play(uint number) payable{
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if (msg.value != 1 ether) throw;
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// <yes> <report> FRONT_RUNNING
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players[tot] = Player(msg.sender, number);
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tot++;
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if (tot==2) andTheWinnerIs();
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}
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function andTheWinnerIs() private {
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bool res ;
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uint n = players[0].number+players[1].number;
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if (n%2==0) {
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res = players[0].addr.send(1800 finney);
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}
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else {
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res = players[1].addr.send(1800 finney);
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}
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delete players;
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tot=0;
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}
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function getProfit() {
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if(msg.sender!=owner) throw;
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bool res = msg.sender.send(this.balance);
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}
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}
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