Perl Requires Chilkat v11.0.0+

Get a Certificate's Key Size

See more Certificates Examples

Demonstrates how to get the RSA key size of a certificate (for example, 1024-bit, 2048-bit, etc.) Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

# For this example, I have a certificate in raw base64 format (not PEM),
# that looks like this:  "MIIGkDCCBHigAwIBAgIUMDA ... s/iqLsLA=="
my $sbCertBase64 = Chilkat2::StringBuilder->new;
my $success = $sbCertBase64->LoadFile('qa_data/certs/base64Cert.txt', 'utf-8');

my $cert = Chilkat2::Cert->new;
$success = $cert->LoadFromBase64($sbCertBase64->GetAsString());
if (!$success) {
    print $cert->LastErrorText, "\n";
    exit;
}

# Get the public key.
my $pubKey = Chilkat2::PublicKey->new;
$cert->GetPublicKey($pubKey);

my $numBits = $pubKey->KeySize;
print 'Number of bits = ', $numBits, "\n";

# If using an older version of Chilkat, the key size can be obtained like this:
my $xml = Chilkat2::Xml->new;
$xml->LoadXml($pubKey->GetXml());

my $binDat = Chilkat2::BinData->new;
$binDat->AppendEncoded($xml->GetChildContent('Modulus'), 'base64');

$numBits = 8 * $binDat->NumBytes;
print 'Number of bits = ', $numBits, "\n";