public bool DecryptData(string signed, string msg = "")
{
if (Init())
{
if (_type == 1)
{
//SHA256 sha256Hash = SHA256.Create();
//byte[] bytes = sha256Hash.ComputeHash(Encoding.UTF8.GetBytes(msg));
byte[] bsigned = StringToByteArray(signed);
byte[] bytes = Encoding.UTF8.GetBytes(msg);
var rsa = RSA.Create();
rsa.KeySize = _keySize;
rsa.ImportSubjectPublicKeyInfo(Convert.FromBase64String(_publicKey), out int byteReads);
var result = rsa.VerifyData(bytes, bsigned, HashAlgorithmName.MD5, RSASignaturePadding.Pkcs1);
return(result);
}
else
{
PGPLib pgp = new PGPLib();
byte[] bytes = Encoding.UTF8.GetBytes(_publicKey);
var stream = new MemoryStream(bytes);
SignatureCheckResult signatureCheck = pgp.VerifyString(signed, stream, out string plainText);
var result = signatureCheck == SignatureCheckResult.SignatureVerified;
return(result);
}
}
else
{
return(false);
}
}
public Boolean Decreypt(string encrypt, int ID)
{
//Get Public File
GetKey objKey = new GetKey();
DataRow drKey = objKey.drSearchStudentKey(ID);
string PublicKey1 = drKey[0].ToString();
// obtain an OpenPGP signed message
String signedString = encrypt;
// Extract the message and check the validity of the signature
String plainText;
// create an instance of the library
PGPLib pgp = new PGPLib();
SignatureCheckResult signatureCheck;
try
{
signatureCheck = pgp.VerifyString(signedString,
new FileInfo(PublicKey1), out plainText);
}
catch
{
return(false);
}
string strData1 = plainText;
// Print the results
Console.WriteLine("Extracted plain text message is " + plainText);
if (signatureCheck == SignatureCheckResult.SignatureVerified)
{
// Console.WriteLine("Signature OK");
return(true);
}
else if (signatureCheck == SignatureCheckResult.SignatureBroken)
{
//Console.WriteLine("Signature of the message is either broken or forged");
return(false);
}
else if (signatureCheck == SignatureCheckResult.PublicKeyNotMatching)
{
// Console.WriteLine("The provided public key doesn't match the signature");
return(false);
}
else if (signatureCheck == SignatureCheckResult.NoSignatureFound)
{
// Console.WriteLine("This message is not digitally signed");
return(false);
}
return(false);
}
public void Decreypt(string encrypt)
{
//Get Public File
GetKey objKey = new GetKey();
int ID = Convert.ToInt32(Session["ID"].ToString());
DataRow drKey = objKey.drSearchStudentKey(ID);
string PublicKey1 = drKey[0].ToString();
// obtain an OpenPGP signed message
String signedString = encrypt;
// Extract the message and check the validity of the signature
String plainText;
// create an instance of the library
PGPLib pgp = new PGPLib();
//SignatureCheckResult signatureCheck = pgp.VerifyString(signedString,
// new FileInfo(@"C:\Users\Dua'a-Orcas\Desktop\finalProject\WebApplication1 - Copy (2)\WebApplication1\Sig\public_key_exported.asc"),
// out plainText);
SignatureCheckResult signatureCheck = pgp.VerifyString(signedString,
new FileInfo(PublicKey1), out plainText);
string strData1 = plainText;
// Print the results
Console.WriteLine("Extracted plain text message is " + plainText);
if (signatureCheck == SignatureCheckResult.SignatureVerified)
{
Console.WriteLine("Signature OK");
Result = true;
}
else if (signatureCheck == SignatureCheckResult.SignatureBroken)
{
Console.WriteLine("Signature of the message is either broken or forged");
}
else if (signatureCheck == SignatureCheckResult.PublicKeyNotMatching)
{
Console.WriteLine("The provided public key doesn't match the signature");
}
else if (signatureCheck == SignatureCheckResult.NoSignatureFound)
{
Console.WriteLine("This message is not digitally signed");
}
}