(Perl) RSA Hash Binary Data and Sign (and Verify)

Demonstrates how to sign the hash of binary data. Also demonstrates how to verify the RSA signature.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux

use chilkat();

$success = 0;

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# Load an RSA private key for signing.
$privKey = chilkat::CkPrivateKey->new();
$success = $privKey->LoadEncryptedPemFile("qa_data/pem/rsa_passwd.pem","passwd");
if ($success == 0) {
    print $privKey->lastErrorText() . "\r\n";
    exit;
}

$rsa = chilkat::CkRsa->new();
$rsa->UsePrivateKey($privKey);

# We have some binary data (in hex) to sign
$originalData = "0102030405060708090A";
$bdData = chilkat::CkBinData->new();
$bdData->AppendEncoded($originalData,"hex");

# Hash (SHA-256) and sign the hash:
$bdSignature = chilkat::CkBinData->new();
$success = $rsa->SignBd($bdData,"sha256",$bdSignature);
if ($success == 0) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

# Show the RSA signature in base64
print $bdSignature->getEncoded("base64") . "\r\n";

# ------------------------------------------
# Get the public key from the private key
$pubKey = chilkat::CkPublicKey->new();
$privKey->ToPublicKey($pubKey);

# Verify the signature..
$rsa2 = chilkat::CkRsa->new();
$rsa2->UsePublicKey($pubKey);

$bVerified = $rsa2->VerifyBd($bdData,"sha256",$bdSignature);
print "signature verified: " . $bVerified . "\r\n";