RSA Sign with PKCS8 Encrypted Key

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature.

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Chilkat.PrivateKey pkey = new Chilkat.PrivateKey();

//  Load the private key from an RSA PEM file:
pkey.LoadPkcs8EncryptedFile("privateKey.key","myPassword");

bool success;

string pkeyXml;
//  Get the private key in XML format:
pkeyXml = pkey.GetXml();

Chilkat.Rsa rsa = new Chilkat.Rsa();

//  Any string argument automatically begins the 30-day trial.

success = rsa.UnlockComponent("30-day trial");
if (success != true) {
    MessageBox.Show("RSA component unlock failed");
    return;
}

//  Import the private key into the RSA component:
success = rsa.ImportPrivateKey(pkeyXml);
if (success != true) {
    MessageBox.Show(rsa.LastErrorText);
    return;
}

//  This example will sign a string, and receive the signature
//  in a hex-encoded string.  Therefore, set the encoding mode
//  to "hex":
rsa.EncodingMode = "hex";

//  If some other non-Chilkat application or web service is going to be verifying
//  the signature, it is important to match the byte-ordering.
//  The LittleEndian property may be set to true
//  for little-endian byte ordering,
//  or false  for big-endian byte ordering.
//  Microsoft apps typically use little-endian, while
//  OpenSSL and other services (such as Amazon CloudFront)
//  use big-endian.
rsa.LittleEndian = false;

string strData;
strData = "This is the string to be signed.";

//  Sign the string using the sha-1 hash algorithm.
//  Other valid choices are "md2", "sha256", "sha384", "sha512",  and "md5".
string hexSig;
hexSig = rsa.SignStringENC(strData,"sha-1");

textBox1.Text += hexSig + "\r\n";