(Perl) CoSign PKCS7/CMS Signed Data

See more Digital Signatures Examples

Demonstrates how to add a 2nd signature to a CMS SignedData. This is to add an additional signature, SignerInfo and certificate(s) to an existing CMS signed data.

In this example, we cosign an existing pdf.p7s

Note: The CoSign method is added in Chilkat v9.5.0.89.

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Perl Module for Windows, MacOS, Linux, Alpine Linux

use chilkat();

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

$crypt = chilkat::CkCrypt2->new();
$cert = chilkat::CkCert->new();

# If loading from a smart card, set the smartcard PIN.
$cert->put_SmartCardPin("0000");

# Load a certificate in some way, such as from a smart card.
# Chilkat provides other methods to load from a .pfx, .pem, or from the Windows certificate stores..
$success = $cert->LoadFromSmartcard("");
if ($success == 0) {
    print $cert->lastErrorText() . "\r\n";
    exit;
}

$success = $crypt->SetSigningCert($cert);
if ($success == 0) {
    print $crypt->lastErrorText() . "\r\n";
    exit;
}

# Load the file to be co-signed.
# NOTE:  This is to cosign a PDF file contained within a CMS (PKCS7) message.
# (In other words, the PDF is contained within the CMS SignedData, rather than the other way around
# where a CMS signature is contained within a PDF.  Use Chilkat's PDF class to sign a PDF, which is
# to embed a CMS signature within the PDF.)
$bd = chilkat::CkBinData->new();
$success = $bd->LoadFile("qa_data/p7s/cosign/sample.pdf.p7s");
if ($success == 0) {
    print "Failed to load pdf.p7s input file." . "\r\n";
    exit;
}

# bd2 will contain the co-signed result.
$bd2 = chilkat::CkBinData->new();
$success = $crypt->CoSign($bd,$cert,$bd2);
if ($success == 0) {
    print $crypt->lastErrorText() . "\r\n";
    exit;
}

$success = $bd->WriteFile("qa_output/cosigned.pdf.p7s");
if ($success == 0) {
    print "Failed to save pdf.p7s output file." . "\r\n";
    exit;
}

print "Success!" . "\r\n";