(PHP Extension) Sign PDF in the Cloud using AWS KMS

See more Signing in the Cloud Examples

Note: This example requires Chilkat v9.5.0.96 or greater.

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<?php

include("chilkat.php");
// Use "chilkat_9_5_0.php" for versions of Chilkat < 10.0.0

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

$pdf = new CkPdf();

// Load a PDF to be signed.
$success = $pdf->LoadFile('qa_data/pdf/helloWorld.pdf');
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

// Options for signing are specified in JSON.
$json = new CkJsonObject();

// Optionally create an LTV-enabled signature
$json->UpdateBool('ltvOcsp',true);

// Define the appearance of the signature.
$json->UpdateInt('page',1);
$json->UpdateString('appearance.y','top');
$json->UpdateString('appearance.x','left');
$json->UpdateString('appearance.fontScale','10.0');
$json->UpdateString('appearance.text[0]','Digitally signed by: cert_cn');
$json->UpdateString('appearance.text[1]','current_dt');
$json->UpdateString('appearance.text[2]','This is an LTV-enabled signature.');

// Load the certificate used for signing.  The certificate's private key is stored in AWS KMS
// However, we still need the certificate locally (without private key).
$cert = new CkCert();
$success = $cert->LoadFromFile('qa_data/certs/myCert.cer');
if ($success == false) {
    print $cert->lastErrorText() . "\n";
    exit;
}

// Here's a screenshot of our private key AWS KMS:


// To sign using AWS KMS, 
// add the following lines of code to specify your AWS authentication credentials,
// and the ID of the KMS private key.
$jsonAwsKms = new CkJsonObject();
// Set the "service" equal to "aws_kms" to tell Chilkat to use AWS KMS for signing.
$jsonAwsKms->UpdateString('service','aws_kms');
$jsonAwsKms->UpdateString('access_key','ACCESS_KEY');
$jsonAwsKms->UpdateString('secret_key','SECRET_KEY');
// Make sure to specify the correct region for your case.
$jsonAwsKms->UpdateString('region','us-west-2');
// In the above screenshot, our key ID is "187012e8-008f-4fc7-b100-5efe6146dff2".  You will use your key ID.
$jsonAwsKms->UpdateString('key_id','187012e8-008f-4fc7-b100-5efe6146dff2');

$success = $cert->SetCloudSigner($jsonAwsKms);

// Tell the pdf object to use the certificate for signing (and for AWS KMS to do the actual signing of the hash).
$success = $pdf->SetSigningCert($cert);
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

// Chilkat will build the signed PDF locally, but will (internally) use AWS KMS
// to do the RSA (or EC) sign hash operation.
$success = $pdf->SignPdf($json,'qa_output/hello_ltv_signed.pdf');
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

print 'PDF Cloud Signing using AWS KMS Successful.' . "\n";

?>