Encrypt in java and decrypt in c#

10y8.2kAlgorithms in C#

I am trying encrypt in java and decrypt in c# with help of querystring for login page concept .Any one send coding for this or send some reference to me.

Thanks in advance

11 Replies

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10y ago
string username=Decrypt(Request.Querystring["UN"]);
string password=Decrypt(Request.Querystring["PWD"]);
using querystring, we call the username and password in c# code and then we want to decrypt the code..

In top of the url:
page1.aspx?UN=ganesh&PWD=admin@1234 .user can visible the password.so we use encrypt and decrypt concept.
Rajesh Singh10y ago
You pass encrypted string as parameter to C# exe or form.
Rajesh Singh10y ago
How you are calling C# page from java?
10y ago
But java encrypt code and c# decrypt code are not matching.I got error like padding is not valid lenght and value on decrypt code in c# .
Rajesh Singh10y ago
@Yuvi

I have username and pasword on login page in java :
You are getting user name and password from java. Encrypt it and pass this string to C# page.
Then decrypt it.

I hope this will help .

Please accept answer if you are satisfied.
10y ago
I have username and pasword on login page in java .After that the user came to webform page(Next page) in c# with help of the query string from java.But user able saw the password and username on top the link.so that we want to encrypt code in java and get the query string from java and then decrypt the code in c#.
Rajesh Singh10y ago
Hi Yuvi
I am not getting ur point.
Please elaborate.
10y ago
Lot of thanks for reply ...

Encrypt coding for java:

final String key = "=abcd!#Axd*G!pxP";
final javax.crypto.spec.SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), "AES");
final javax.crypto.Cipher cipher = Cipher.getInstance(""AES/ECB/NoPadding"");
cipher.init(Cipher.ENCRYPT_MODE, keySpec);
byte [] encryptedValue = cipher.doFinal(input.getBytes());
return new String(org.apache.commons.codec.binary.Hex.encodeHex(encryptedValue));

Decrypt coding for C#:

RijndaelManaged rijndaelCipher = new RijndaelManaged();
// Assumed Mode and padding values.
rijndaelCipher.Mode = CipherMode.ECB;
rijndaelCipher.Padding = PaddingMode.None;
// AssumedKeySize and BlockSize values.
rijndaelCipher.KeySize = 0x80;
rijndaelCipher.BlockSize = 0x80;
// Convert Hex keys to byte Array.
byte[] encryptedData = hexStringToByteArray(textToDecrypt);
byte[] pwdBytes = System.Text.Encoding.GetEncoding("ISO-8859-1").GetBytes(key);
byte[] keyBytes = new byte[0x10];
int len = pwdBytes.Length;
if (len > keyBytes.Length)
{
len = keyBytes.Length;
}
Array.Copy(pwdBytes, keyBytes, len);
rijndaelCipher.Key = keyBytes;
rijndaelCipher.IV = keyBytes;
// Decrypt data
byte[] plainText = rijndaelCipher.CreateDecryptor().TransformFinalBlock(encryptedData, 0, encryptedData.Length);
str = Encoding.UTF8.GetString(plainText);
static private byte[] HexToBytes(string str)
{
if (str.Length == 0 || str.Length % 2 != 0)
return new byte[0];
byte[] buffer = new byte[str.Length / 2];
char c;
for (int bx = 0, sx = 0; bx < buffer.Length; ++bx, ++sx)
{
// Convert first half of byte
c = str[sx];
buffer[bx] = (byte)((c > '9' ? (c > 'Z' ? (c - 'a' + 10) : (c - 'A' + 10)) : (c - '0')) << 4);
// Convert second half of byte
c = str[++sx];
buffer[bx] |= (byte)(c > '9' ? (c > 'Z' ? (c - 'a' + 10) : (c - 'A' + 10)) : (c - '0'));
}
return buffer;
}
This is correct coding for encrypt and decrypt coding above u mentioned on this link...
Rajesh Singh10y ago
Hi Yuvi
Encrypt string in java and pass encrypted string to C# as parameter and use decryption cod e in C#. Both code are available in link provided.

Please let me know my understanding.
10y ago
Thanks for communication. But on that link both are encrypt and decrypt in java as it as same in c# concept...but i need to encrypt in java and decrypt in C# using query string.I got confused on that link and my coding was not running.can u send coding for me..:)
Rajesh Singh10y ago
Hi Yuvi
Please refer this link.
http://stackoverflow.com/questions/5295110/aes-encryption-in-java-and-decryption-in-c-sharp