I am passing one encrypted key as URL argument and after receiving the key, I am trying to decrypt the key but getting bad arguments exception at a particular portion of the code. I am not understanding where is the issue and how to resolve it. Hereby requesting you to help me on this. I have mentioned the code line where i am getting the error in the console part below.
Source(A legacy java application where generating the encrypted key):
StrongAES strong_AES = new StrongAES();
id = strong_AES.encrypt_Data(user_string_2bEncrypted);
c = strong_AES.count_Cipher();
<a href="url/id=<%=id%>&c=<%=c%>">
StrongAES Class
public class StrongAES {
byte[] input;
byte[] cipher_Text;
SecretKeySpec Key;
int ctLength;
public byte[] encrypt_Data(String data){
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
byte[] input = data.getBytes();
this.input = input;
byte[] keyBytes = new byte[] {'T', 'h', 'i', 's', 'I', 's', 'A', 'S', 'e', 'c', 'r', 'e', 't', 'K', 'e', 'y'};
SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
this.Key = key;
byte[] cipherText = null;
Cipher cipher;
try {
cipher = Cipher.getInstance("AES/ECB/PKCS7Padding", "BC");
cipher.init(Cipher.ENCRYPT_MODE, key);
cipherText = new byte[cipher.getOutputSize(input.length)];
int ctLength = cipher.update(input, 0, input.length, cipherText, 0);
ctLength += cipher.doFinal(cipherText, ctLength);
this.cipher_Text = cipherText;
this.ctLength = ctLength;
....
....
return cipherText;
}
public int count_Cipher(){
return this.ctLength;
}
Destination(An application written in Spring MVC):
HomeController.java
@RequestMapping(value = "/id={id}", method = RequestMethod.GET)
public String getMethod(@PathVariable(value = "id") String id ,@RequestParam int c ,ModelMap model, HttpServletRequest request){
System.out.println("key value is : "+id);
System.out.println("lenth is :"+c);
StrongAES strong_AES = new StrongAES();
String login = null;
try {
login = strong_AES.decrypt_Data(id.getBytes(),c);
System.out.println("decrypted login id is -"+login.toString());
} catch (InvalidAlgorithmParameterException e) {
e.printStackTrace();
}
StrongAES Class
public class StrongAES {
public void encrypt_Data(){
}
public String decrypt_Data(byte[] cipherText, int ctLength) throws InvalidAlgorithmParameterException{
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
byte[] keyBytes = new byte[] {'T', 'h', 'i', 's', 'I', 's', 'A', 'S', 'e', 'c', 'r', 'e', 't', 'K', 'e', 'y'};
SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
System.out.println("byte length - "+cipherText.length);
Cipher cipher;
byte[] plainText = null;
try {
cipher = Cipher.getInstance("AES/ECB/PKCS7Padding","BC");
cipher.init(Cipher.DECRYPT_MODE, key);
//decrypt
plainText = new byte[cipher.getOutputSize(ctLength)];
System.out.println("cipherText - "+cipherText+" ctLength - "+ctLength+" plainText - "+plainText);
int ptLength = cipher.update(cipherText, 0, ctLength, plainText,0);
System.out.println("ptLength - "+ptLength);
ptLength += cipher.doFinal(plainText, ptLength);
return new String(plainText);
Console Output:
key value is : [B@b2c64
lenth is :16
byte length - 8
cipherText - [B@19125a3 ctLength - 16 plainText - [B@3e2052
Dec 17, 2014 7:09:27 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [appServlet] in context with path [/app] threw exception [Request processing failed; nested exception is java.lang.IllegalArgumentException: Bad arguments] with root cause
java.lang.IllegalArgumentException: Bad arguments
at javax.crypto.Cipher.update(Cipher.java:1860)
at com.myproject.ERA.form.model.StrongAES.decrypt_Data(StrongAES.java:38) // this is the line - int ptLength = cipher.update(cipherText, 0, ctLength, plainText,0);
at com.myproject.ERA.HomeController.getMethod(HomeController.java:69)
