java decrytpion & c# encryption Illegal key size issue

Question

We were encrypting/decrypting our organization's document from this code by a c# application

var msData = new MemoryStream();
            CryptoStream cs = null;
            if (inputFileStream.CanSeek)
                inputFileStream.Seek(0, SeekOrigin.Begin);
            try
            {
                long inputFileLength = inputFileStream.Length;
                var byteBuffer = new byte[4096];
                long bytesProcessed = 0;
                int bytesInCurrentBlock = 0;

                var csRijndael = new RijndaelManaged();
                switch (action)
                {
                    case CryptoAction.Encrypt:
                        cs = new CryptoStream(msData, csRijndael.CreateEncryptor(this.Key, this.IV), CryptoStreamMode.Write);
                        break;

                    case CryptoAction.Decrypt:
                        cs = new CryptoStream(msData, csRijndael.CreateDecryptor(this.Key, this.IV), CryptoStreamMode.Write);
                        break;
                }

                while (bytesProcessed < inputFileLength)
                {
                    bytesInCurrentBlock = inputFileStream.Read(byteBuffer, 0, 4096);
                    cs.Write(byteBuffer, 0, bytesInCurrentBlock);
                    bytesProcessed += bytesInCurrentBlock;
                }
                cs.FlushFinalBlock();

                return msData.ToArray();
            }
            catch(Exception ex)
            {
                new Com.Library.SqlLog().InsertSqlLog(Auth.currentMemberInfo.LoginId, MethodInfo.GetCurrentMethod().Name, ex);
                return null;
            }

and it is working fine.Now I am creating a Java application which is supposed to decrypt these documents too.Initially I tried to decrypt documents by this code of Java

 try{


    AlgorithmParameterSpec paramSpec = new IvParameterSpec(IV); 
    Cipher cipher = Cipher.getInstance("AES");
    SecretKeySpec key = new SecretKeySpec(keyGen, "AES");
    cipher.init(Cipher.DECRYPT_MODE, key, paramSpec); 
    byte[] output =  new BASE64Decoder().decodeBuffer(new String(convertDocToByteArra("//Path/somePDF.pdf")));  

     byte[] decrypted = cipher.doFinal(output);

     convertByteArrayToDoc(decrypted);
       }catch(Exception e){
           e.printStackTrace();
       }

Now here is my problem.I passed this as init vector

static byte IV[] = new byte[] {0x0E,0x15,(byte)0xC4,(byte)0xBB,
             (byte)0xEE,(byte)0xDF,0x72,0x0C,0x4F,0x7E,(byte)0xBE,0x67,0x4A,(byte)0xB6,0x45,(byte)0xDE};

and this as a key

static byte[] keyGen = new byte[]{0x78,(byte)0x9C,(byte)0xF1,0x01,0x12,0x31,(byte)0xCD,0x1E,0x1F,0x16,0x54,0x19,0x1D,(byte)0xFF,(byte)0xC7,
            0x00,0x51,(byte)0xBF,(byte)0xFD,0x31,(byte)0xE1,(byte)0xA1,(byte)0xDC,(byte)0xC9,0x23,0x49,(byte)0xAD,0x11,0x16,0x17,0x1D,0x1F};

But when I run this program then it throws an exception given below

java.security.InvalidKeyException: Illegal key size
    at javax.crypto.Cipher.checkCryptoPerm(Cipher.java:1023)
    at javax.crypto.Cipher.implInit(Cipher.java:789)
    at javax.crypto.Cipher.chooseProvider(Cipher.java:848)
    at javax.crypto.Cipher.init(Cipher.java:1347)
    at javax.crypto.Cipher.init(Cipher.java:1281)
    at DecryptAspEncryptedDocs.main(DecryptAspEncryptedDocs.java:80)

Now I am stuck here and don't know what to do.Any help would be greatly appreciated.

EDIT 1:
I have seen this question and jars are placed in jre/lib/security and jdk/lib/security.But still issue is pending and throwing illegal key size exception

@GregS I have provided AES/CBC/NoPadding but it is again saying "Illegal keysize" — Despicable, Jan 24 '13 at 03:44
As I said it works for me and I know I have the unlimited crypto policy jars installed. It seems like that you do not, despite your beliefs. Perhaps you have multiple versions of Java installed, or you have mis-installed the policy files. — President James K. Polk, Jan 24 '13 at 03:51
Can you post your code for help.May be I was doing wrong somewhere — Despicable, Jan 24 '13 at 09:52
I just used your code. I copy&pasted the lines from your example up to and including the `cipher.init()` line and copy&pasted your keyGen and IV. — President James K. Polk, Jan 24 '13 at 12:29
@GregS can the policy files limitation can be overcome by using BouncyCastle API ? — Dakait, Jan 29 '13 at 08:06
@dakait: Yes, if you use the Bouncycastle lightweight API. That's different than using the JCE APIs with the Bouncycastle provider. The latter won't help at all. — President James K. Polk, Jan 29 '13 at 23:49

score 1 · Answer 1 · answered Jan 23 '13 at 06:35

1

Depending on the key size for AES then it will be subject to export controls. I suggest that you download the unlimited jce jurisdiction policy files and install them into your Java environment.

AES256 will require the unlimited the policy files.

answered Jan 23 '13 at 06:35

quotidian-ennui

116
3

yes I aleady did that by reviewing this question http://stackoverflow.com/questions/6481627/java-security-illegal-key-size-or-default-parameters – Despicable Jan 23 '13 at 06:40

score 0 · Answer 2 · answered Sep 20 '13 at 17:35

0

It's not stated clearly in README that "JCE Unlimited Strength Jurisdiction Policy Files" should be copied to jre inside your JDK, otherwise it would not work. Path for files should be: /path/to/jdk1.7.0_xx/jre/lib/security

answered Sep 20 '13 at 17:35

ruruskyi

2,018
2
26
37

java decrytpion & c# encryption Illegal key size issue

2 Answers2