RSA Signature/Verify with .key and .cer

Demonstrates how to use a .key file (private key) and digital certificate (.cer, public key) to create and verify an RSA signature.

Chilkat Module for Perl 5.8.*

Chilkat Module for Perl 5.10.*

Chilkat Module for Perl 5.8.* (x64)

Chilkat Module for Perl 5.10.* (x64)

use chilkat;

$privKey = new chilkat::CkPrivateKey();

#  Load the private key from an RSA .key file:
$success = $privKey->LoadPemFile("privateKey.key");
if ($success != 1) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

#  Get the private key in XML format:
$privKeyXml = $privKey->getXml();

$rsa = new chilkat::CkRsa();

#  Any string argument automatically begins the 30-day trial.
$success = $rsa->UnlockComponent("30-day trial");
if ($success != 1) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

#  Import the private key into the RSA component:
$success = $rsa->ImportPrivateKey($privKeyXml);
if ($success != 1) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

#  Create the signature as a hex string:
$rsa->put_EncodingMode("hex");

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

#  Sign the string using the sha-1 hash algorithm.
#  Other valid choices are "md2" and "md5".
$hexSig = $rsa->signStringENC($strData,"sha-1");

print $hexSig . "\r\n";

#  Load a digital certificate from a .cer file:
$cert = new chilkat::CkCert();

$success = $cert->LoadFromFile("myCert.cer");
if ($success != 1) {
    print $cert->lastErrorText() . "\n";
    exit;
}

# pubKey is a CkPublicKey
$pubKey = $cert->ExportPublicKey();

#  Now verify using a separate instance of the RSA object:
$rsa2 = new chilkat::CkRsa();

#  Import the public key into the RSA object:
$success = $rsa2->ImportPublicKey($pubKey->getXml());
if ($success != 1) {
    print $rsa2->lastErrorText() . "\n";
    exit;
}

#  The signature is a hex string, so make sure the EncodingMode is correct:
$rsa2->put_EncodingMode("hex");

#  Verify the signature:
$success = $rsa2->VerifyStringENC($strData,"sha-1",$hexSig);
if ($success != 1) {
    print $rsa2->lastErrorText() . "\n";
    exit;
}

print "Success." . "\n";