Perl

Generate RSA Key and Sign a String

See more RSA Examples

Demonstrates how to generate a new RSA public/private key pair and use it to generate a signature for a string. The (binary) digital signature is returned as a hexidecimalized string. Perl

use chilkat();

$success = 0;

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

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

# Generate a 2048-bit RSA key.
$privKey = chilkat::CkPrivateKey->new();
$success = $rsa->GenKey(2048,$privKey);

$rsa->UsePrivateKey($privKey);

# Return the signature in hex.
$rsa->put_EncodingMode("hex");

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

# Sign the SHA256 hash of the string.
$hexSig = $rsa->signStringENC($strData,"sha256");

print $hexSig . "\r\n";

# Now verify the signature:
$pubKey = chilkat::CkPublicKey->new();
$privKey->ToPublicKey($pubKey);
$rsa->UsePublicKey($pubKey);

$success = $rsa->VerifyStringENC($strData,"sha256",$hexSig);
if ($success == 1) {
    print "Signature verified!" . "\r\n";
}
else {
    print $rsa->lastErrorText() . "\r\n";
}

# Try it with an invalid signature:
$success = $rsa->VerifyStringENC($strData,"sha256","not a valid sig");
if ($success == 1) {
    print "Signature verified!" . "\r\n";
}
else {
    print "Signature validation failed!" . "\r\n";
}

# Try it with invalid data:
$success = $rsa->VerifyStringENC("Not the original data","sha256",$hexSig);
if ($success == 1) {
    print "Signature verified!" . "\r\n";
}
else {
    print "Signature validation failed!" . "\r\n";
}