[C#]RSACryptoServiceProvider Bad Data Error

[Darkc0der]

Gan, ane punya masalah nih.



Ceritanya, ane mo coding program buat encrypt ama decrypt file pake RSA.



Waktu proses Enkripsi gak masalah gan.



Masalahnya muncul waktu proses dekripsi.



Begitu sampe line yang ane bold, programnya langsung ngeluarin exception bad data.



Parahnya, tu exception tidak selalu terjadi. Pernah berhasil 1-2 kali, sisanya keluar exception tadi.



Succesful rate kira2 2% lah.



Ntu kira2 salahnya dimana ya gan?



Any help will be appreciated. Thx.


Code:


namespace enryptdecrypt
{
public class clsRSA:ApplicationException
{
private string mPrivateKey;
private string mPublicKey;

private RSACryptoServiceProvider objRSA = new RSACryptoServiceProvider();

public string PrivateKey
{
get
{
return mPrivateKey;
}
set
{
//string value;
mPrivateKey = value;
}
}
public string PublicKey
{
get
{
return mPublicKey;
}
set
{
//string value;
mPublicKey = value;
}
}
public object CreateNewKeys()
{
RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
//Generate Private Key
mPrivateKey = RSA.ToXmlString(true);
//Generate Public Key
mPublicKey = RSA.ToXmlString(false);
return null;
}
public void SaveKeyToFile(string PrivateKeyPath, string PublicKeyPath)
{
try
{
SaveTextToFile(PrivateKey, PrivateKeyPath);
SaveTextToFile(PublicKey, PublicKeyPath);
//return null;
}
catch (Exception ex)
{
Interaction.MsgBox(ex.Message, MsgBoxStyle.OkOnly, "Error !!!");
//return null;
}
}
public void LoadKeyFromFile(string PrivateKeyPath, string PublickeyPath)
{
try
{
PrivateKey = GetFileContents(PrivateKeyPath);
PublicKey = GetFileContents(PublickeyPath);
//return null;
}
catch (Exception ex)
{
Interaction.MsgBox(ex.Message, MsgBoxStyle.OkOnly, "Error !!!");
//return null;
}
}
public string StringEncrypt(string strSource)
{
byte[] bufSource = null;
string strEncrypted = null;
try
{
//use public key to encrypt
objRSA.FromXmlString(PublicKey);
//convert Source String into byte array and encrypt it
bufSource = objRSA.Encrypt(Encoding.Unicode.GetBytes(strSource ),false);
//convert Crypted byte array into string
strEncrypted = Encoding.Unicode.GetString(bufSource);

return(strEncrypted);
}
catch (Exception ex)
{
Interaction.MsgBox(ex.Message, MsgBoxStyle.OkOnly, "Error");
return null;
}
}
public string StringDecrypt(string strSource)
{
byte[] bufSource = null;
string strDecrypted = null;

try
{
//use private key to decrypt
objRSA.FromXmlString(PrivateKey);
//convert source string into byte array and decrypte it
bufSource = objRSA.Decrypt(Encoding.Unicode.GetBytes(strSource ), false);
//convert decrypted byte array into string
strDecrypted = Encoding.Unicode.GetString(bufSource);

return (strDecrypted);
}
catch(Exception ex)
{
throw(ex);
}
}
public bool FileEncrypt(string InName, string OutName)
{
string sContents = null;
string strEncrypted = null;

sContents = GetFileContents(InName);
strEncrypted = StringEncrypt(sContents);

byte[] bufSource;
bufSource = Encoding.UTF8.GetBytes(strEncrypted);
strEncrypted = System.Convert.ToBase64String(bufSource);

if (SaveTextToFile(strEncrypted, OutName) == true)
{
return true;
}
else
return false;
}
public bool FileDecrypt(string InName, string OutName)
{
string sContents = null;
string strEncrypted = null;
byte[] bufSource;

sContents = GetFileContents(InName);
bufSource = System.Convert.FromBase64String(sContents);
sContents = Encoding.UTF8.GetString(bufSource);
strEncrypted = StringDecrypt(sContents);

if (SaveTextToFile(strEncrypted, OutName) == true)
{
return true;
}
else
return false;
}
//private string[] arrFiles1;
private string GetFileContents(string FullPath)
{
string strContents = null;
StreamReader objReader = default(StreamReader);
try
{
objReader = new StreamReader(FullPath);
strContents = objReader.ReadToEnd();
objReader.Close();
return strContents;
}
catch (Exception Ex)
{
throw new ApplicationException("Read Input File Error !!!");
}
}
private bool SaveTextToFile(string strData, string FullPath)
{
string Contents = null;
bool bAns = false;
StreamWriter objReader = default(StreamWriter);

try
{
objReader = new StreamWriter(FullPath);
objReader.Write(strData);
objReader.Close();
bAns = true;
}
catch (Exception Ex)
{
throw new ApplicationException("Write Output File Error!!!");
}
return bAns;
}
/*private long FillRecursiveArray(String strSourcePath)
{
int Cmptr = 0;
ArrayList lstStringFolders = new ArrayList();
string[] strSubFolders = null;
ArrayList lstSortedFolders = new ArrayList();
string bufFolder = null;
string bufFile = null;

try
{
//Set initial Path
lstStringFolders.Add(strSourcePath);
//String[] arrFiles1 = new String;
String[] arrFiles2 = new String[0];
Array.Copy(arrFiles1, arrFiles2, arrFiles2.Length);
while (!(Cmptr == lstStringFolders.Count))
{
strSubFolders = System.IO.Directory.GetDirectories(lstStringFolder s.Item(Cmptr));
lstStringFolders.AddRange(strSubFolders);
Cmptr = Cmptr+1;
//return Cmptr;
}
}
catch (Exception ex)
{
throw new ApplicationException("Folder Recursion Error !!!");
}
try
{
//Sort, to get sub-folde under his mother folder
lstStringFolders.Sort();
foreach (var bufFolder in lstStringFolders)
{
lstStringFolders.Add(bufFolder);
}
}
catch(Exception ex)
{
throw new ApplicationException("Folder Sort Error");
}
try
{
//for each folder
foreach (var bufFolder in lstStringFolders)
{
//for each File
foreach (var bufFile in Directory.GetFiles(bufFolder))
{
//set File Path into private array
Array.Resize(ref arrFiles1, Information.UBound(arrFiles1) + 2);

arrFiles1(Information.UBound(arrFiles1)) = bufFile;
}
}
}
catch (Exception ex)
{
throw new ApplicationException("File Recursion Error !!!");
}
return arrFiles1.Length;
}
private long FillNonRecursiveArray(string strSourcePath)
{
string bufFile = null;
//File Name Buffer
//ReDim
//File Path Array(Only in initial path)
try
{
//for each file in the initial folder
foreach (var bufFile in Directory.GetFiles(strSourcePath))
{
//set FIle Path in private array
Array.Resize(ref arrFiles1, Information.UBound(arrFiles1) + 2);
arrFiles1(Information.UBound(arrFiles1)) = bufFile;
}
}
catch (Exception ex)
{
throw new ApplicationException("Error, can't list Initial Path File");
}
return arrFiles1.Length;
}*/
}
}