Perl

Create CMS Signed File (PDF) with Multiple Signing Certificates

See more Digital Signatures Examples

Demonstrates how to sign a file by adding multiple signatures (multiple certificates). This example signs a PDF file to produce an output file that is a CMS signature wrapping the original PDF. (Note: This is different than modifying a PDF by injecting a signature into the PDF file format.)

Note: This example requires Chilkat v9.5.0.83 or greater.

Perl

use chilkat();

$success = 0;

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

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

# ------------ This example requires Chilkat v9.5.0.83 or greater.

$cert1 = chilkat::CkCert->new();
$success = $cert1->LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123");
if ($success != 1) {
    print $cert1->lastErrorText() . "\r\n";
    exit;
}

$cert2 = chilkat::CkCert->new();
$success = $cert2->LoadPfxFile("qa_data/pfx/test_secret.pfx","secret");
if ($success != 1) {
    print $cert2->lastErrorText() . "\r\n";
    exit;
}

# ------------ This example requires Chilkat v9.5.0.83 or greater.

# Tell the crypt component to use both certificates for signing. 
# When we create the signature, it will be signed by both certificates.
$success = $crypt->AddSigningCert($cert1);
if ($success != 1) {
    print $crypt->lastErrorText() . "\r\n";
    exit;
}

$success = $crypt->AddSigningCert($cert2);
if ($success != 1) {
    print $crypt->lastErrorText() . "\r\n";
    exit;
}

# The CadesEnabled property applies to all methods that create PKCS7 signatures. 
# To create a CAdES-BES signature, set this property equal to true. 
$crypt->put_CadesEnabled(1);

$crypt->put_HashAlgorithm("sha256");

# We can sign any type of file, creating a .p7s as output.
# The .p7s contains the signature and also embeds the data of the file that is signed.
$inFile = "qa_data/pdf/sample.pdf";
$p7sFile = "qa_output/sample.pdf.p7s";

# Create the CAdES-BES attached signature, which contains the original data.
# Note: Chilkat's function naming is not accurate.  CreateP7M creates a PKCS7 signature where the signed file
# is contained within the signature.  CreateP7S creates a detached PKCS7 signature where the signed file
# is NOT contained within the signature.  We want the data to be contained in the signature, therefore
# we call CreateP7M even though we are naming our output file .p7s.
$success = $crypt->CreateP7M($inFile,$p7sFile);
if ($success == 0) {
    print $crypt->lastErrorText() . "\r\n";
    exit;
}

# Verify the .p7s file and extract the original file from the .p7s. 
$extractedToFilePath = "qa_output/sample.pdf";
$success = $crypt->VerifyP7M($p7sFile,$extractedToFilePath);
if ($success == 0) {
    print $crypt->lastErrorText() . "\r\n";
    exit;
}

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