File size: 1,847 Bytes
5c59a6a | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 | import java.net.URLDecoder;
import java.util.*;
class VaultDoor5 {
public static void main(String args[]) {
VaultDoor5 vaultDoor = new VaultDoor5();
Scanner scanner = new Scanner(System.in);
System.out.print("Enter vault password: ");
String userInput = scanner.next();
String input = userInput.substring("picoCTF{".length(),userInput.length()-1);
if (vaultDoor.checkPassword(input)) {
System.out.println("Access granted.");
} else {
System.out.println("Access denied!");
}
}
// Minion #7781 used base 8 and base 16, but this is base 64, which is
// like... eight times stronger, right? Riiigghtt? Well that's what my twin
// brother Minion #2415 says, anyway.
//
// -Minion #2414
public String base64Encode(byte[] input) {
return Base64.getEncoder().encodeToString(input);
}
// URL encoding is meant for web pages, so any double agent spies who steal
// our source code will think this is a web site or something, defintely not
// vault door! Oh wait, should I have not said that in a source code
// comment?
//
// -Minion #2415
public String urlEncode(byte[] input) {
StringBuffer buf = new StringBuffer();
for (int i=0; i<input.length; i++) {
buf.append(String.format("%%%2x", input[i]));
}
return buf.toString();
}
public boolean checkPassword(String password) {
String urlEncoded = urlEncode(password.getBytes());
String base64Encoded = base64Encode(urlEncoded.getBytes());
String expected = "JTYzJTMwJTZlJTc2JTMzJTcyJTc0JTMxJTZlJTY3JTVm"
+ "JTY2JTcyJTMwJTZkJTVmJTYyJTYxJTM1JTY1JTVmJTM2"
+ "JTM0JTVmJTY1JTMzJTMxJTM1JTMyJTYyJTY2JTM0";
return base64Encoded.equals(expected);
}
}
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