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Perl

Export a Public Key as DER into a BinData

Demonstrates the Chilkat PublicKey.GetDerBd method, which writes the public key as binary DER into a BinData. The first argument selects the representation (as for GetPem) and the second is the BinData that receives the bytes (its contents are replaced).

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: The in-memory binary export: the raw DER lands in a BinData ready to hash, transmit, or hand to another API without a temporary file. It is the BinData counterpart to the text exporters, and the first argument picks the same PKCS #1 versus SubjectPublicKeyInfo structure.

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Chilkat2 Perl
use strict;
use warnings;
use Chilkat2;

# Load a public key to export.  LoadFromFile inspects the content, so it accepts DER, PEM, XML,
# JWK, and other supported representations.
my $pubKey = Chilkat2::PublicKey->new;
my $success = $pubKey->LoadFromFile('qa_data/public.pem');
if (!$success) {
    print $pubKey->LastErrorText, "\n";
    exit;
}

# Write the public key as binary DER into a BinData.  The 1st argument selects the representation
# (as for GetPem) and the 2nd is the BinData that receives the bytes (its contents are replaced).
my $preferPkcs1 = 0;
my $bd = Chilkat2::BinData->new;
$success = $pubKey->GetDerBd($preferPkcs1, $bd);
if (!$success) {
    print $pubKey->LastErrorText, "\n";
    exit;
}

print 'Exported ', $bd->NumBytes, " DER bytes.\n";