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@Still34

Still34/oop.java Secret

Created Jul 15, 2020
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//I heard Java 11 is good, let's use that
import java.io.*;
import java.math.*;
import java.util.*;
import java.lang.reflect.*;//think of this as #include <stdio.h>, basically every program needs it for IO
public class Main {
//it's always good practice to declare constants for unclear magic values
public static final int ZERO = BigInteger.valueOf(0).intValue();//BigInteger for precision
public static final int ONE = BigInteger.valueOf(1).intValue();
public static final int TWO = BigInteger.valueOf(2).intValue();
public static final int THREE = BigInteger.valueOf(3).intValue();
public static final int FOUR = BigInteger.valueOf(4).intValue();
public static final int SEVEN = BigInteger.valueOf(7).intValue();
public static final int SIXTEEN = BigInteger.valueOf(16).intValue();
public static void main(String[] args) throws Exception { //running Java is dangerous, that's why everything throws an Exception
InputStream standardInputStream = new StandardInputStreamInstantiator().getStandardInputStreamFactory().getStandardInputStream();
//i'm going to take a shortcut here, behold the power of java libraries - so many lines saved!
Scanner scanner = Scanner.class.getConstructor(standardInputStream.getClass().getSuperclass().getSuperclass()).newInstance(standardInputStream);
PrintStream outputPrintStream = new OutputPrintStreamInstantiator().getOutputPrintStreamFactory().getOutputPrintStream();
Method printLineMethod = getPrintLineMethodForOutputPrintStream(outputPrintStream);
invokePrintLineMethodForOutputPrintStream(outputPrintStream, printLineMethod, "IO is online.");
//IO Setup
String userInput = getUserInputMethodFromScannerAndInvokeAndReturnOutput(scanner);
if (userInput.length() != SIXTEEN)
System.exit(0);
if (executeCodeThatDoesSomethingThatYouProbablyNeedToFigureOut(userInput).equals(scanner.getClass().getPackageName().replace(".", ""))) {
invokePrintLineMethodForOutputPrintStream(outputPrintStream, printLineMethod, "Nice. Flag: rgbCTF{" + userInput + "}");
} else {
invokePrintLineMethodForOutputPrintStream(outputPrintStream, printLineMethod, "Try again.");
}
}
public static String executeCodeThatDoesSomethingThatYouProbablyNeedToFigureOut(String stringToExecuteAforementionedCodeOn) throws Exception {
String encryptedString = reallyBasicQuoteUnquoteEncryptionFunctionThatWillOnlyTakeTimeToFigureOutIfYouKeepReadingTheseRidiculouslyLongMethodNames(stringToExecuteAforementionedCodeOn);
String returnValueOfThisFunction = new String();
String[] chunksOfEncryptedStringOfLengthFour = splitStringIntoChunksOfLength(encryptedString, FOUR);
for (String chunkOfEncryptedStringOfLengthFour : chunksOfEncryptedStringOfLengthFour) {
String[] chunksOfChunkOfEncryptedStringOfLengthFourOfLengthTwo = splitStringIntoChunksOfLength(chunkOfEncryptedStringOfLengthFour, TWO);
String firstChunkOfChunkOfEncryptedStringOfLengthFourOfLengthTwo = chunksOfChunkOfEncryptedStringOfLengthFourOfLengthTwo[0];
String secondChunkOfChunkOfEncryptedStringOfLengthFourOfLengthTwo = chunksOfChunkOfEncryptedStringOfLengthFourOfLengthTwo[1];
Class<?> classAndExtraCharactersSoItsNotAKeyword = Class.forName(firstChunkOfChunkOfEncryptedStringOfLengthFourOfLengthTwo);
Object object = classAndExtraCharactersSoItsNotAKeyword.getConstructors()[ZERO].newInstance();
for (int loopArbitraryCounterIterator = 0; loopArbitraryCounterIterator < THREE; loopArbitraryCounterIterator++) {
Method method = classAndExtraCharactersSoItsNotAKeyword.getMethod(secondChunkOfChunkOfEncryptedStringOfLengthFourOfLengthTwo);
secondChunkOfChunkOfEncryptedStringOfLengthFourOfLengthTwo = (String)method.invoke(object);
}
returnValueOfThisFunction = new String(returnValueOfThisFunction + secondChunkOfChunkOfEncryptedStringOfLengthFourOfLengthTwo);
}
return returnValueOfThisFunction;
}
protected static char secureEncryptionKey; //it's protected, how you gonna crack it now?
public static String reallyBasicQuoteUnquoteEncryptionFunctionThatWillOnlyTakeTimeToFigureOutIfYouKeepReadingTheseRidiculouslyLongMethodNames(String stringToQuoteUnquoteEncrypt) throws Exception {
secureEncryptionKey = new EncryptionKeyInstantiator().getEncryptionKeyFactory().getEncryptionKey();
Integer[] encryptedArrayToBeCalledByStringConstructor = new Integer[stringToQuoteUnquoteEncrypt.length()];
for (int loopIndexIterator = ZERO; loopIndexIterator < stringToQuoteUnquoteEncrypt.length(); loopIndexIterator++) {
encryptedArrayToBeCalledByStringConstructor[loopIndexIterator] = stringToQuoteUnquoteEncrypt.charAt(loopIndexIterator)^secureEncryptionKey;
}
return Arrays.toString(Arrays.asList(encryptedArrayToBeCalledByStringConstructor).stream().map((currentIntegerToBeMapped) -> (char)(currentIntegerToBeMapped.intValue())).toArray(Character[]::new)).replaceAll(", ", "").substring(1, stringToQuoteUnquoteEncrypt.length() + ONE);
}
public static String[] splitStringIntoChunksOfLength(String stringToSplit, int lengthOfChunk) {
String[] returnValueOfThisFunction = new String[stringToSplit.length() / lengthOfChunk];
for (int loopChunkNumberIterator = ZERO; loopChunkNumberIterator < stringToSplit.length() / lengthOfChunk; loopChunkNumberIterator++) {
returnValueOfThisFunction[loopChunkNumberIterator] = stringToSplit.substring(loopChunkNumberIterator * lengthOfChunk, loopChunkNumberIterator * lengthOfChunk + lengthOfChunk);
}
return returnValueOfThisFunction;
}
private static class EncryptionKeyInstantiator {
public EncryptionKeyFactory getEncryptionKeyFactory() {
return new EncryptionKeyFactory();
}
private class EncryptionKeyFactory {
public char getEncryptionKey() {
return (char)(this.getClass().getCanonicalName().charAt(SEVEN) - this.getClass().getCanonicalName().charAt(ONE));
}
}
}
//IO Setup Setup
public static String getUserInputMethodFromScannerAndInvokeAndReturnOutput(Scanner scanner) throws Exception {
return (String)scanner.getClass().getMethod("nextLine").invoke(scanner);
}
public static void invokePrintLineMethodForOutputPrintStream(PrintStream outputPrintStream, Method printLineMethodToInvoke, String stringToBePrintedByPrintLineMethod) throws Exception {
printLineMethodToInvoke.invoke(outputPrintStream, stringToBePrintedByPrintLineMethod);
}
public static Method getPrintLineMethodForOutputPrintStream(PrintStream outputPrintStream) throws Exception{
return outputPrintStream.getClass().getMethod("println", String.class);
}
private static class OutputPrintStreamInstantiator {
public OutputPrintStreamFactory getOutputPrintStreamFactory() throws Exception{
return new OutputPrintStreamFactory();
}
private class OutputPrintStreamFactory {
public PrintStream getOutputPrintStream() throws Exception {
return (PrintStream)System.class.getDeclaredField("out").get(null);
}
}
}
private static class StandardInputStreamInstantiator {
public StandardInputStreamFactory getStandardInputStreamFactory() throws Exception {
return new StandardInputStreamFactory();
}
private class StandardInputStreamFactory {
public InputStream getStandardInputStream() throws Exception {
return (InputStream)System.class.getDeclaredField("in").get(null);
}
}
}
}
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