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PHP Extension

Duplicate OpensSSL to Create Signature using Cert and Key Files

See more OpenSSL Examples

This example duplicates the following:
openssl smime –sign -in something.xml -out something.der -signer mycert.crt -inkey cert.key -outform der –nodetach

Note: Although "smime" is the OpenSSL command, it's not actually producing S/MIME. The arguments "-outform der -binary" indicates that the output is binary DER (i.e. the PKCS7 binary signature). The input can be any type of file: XML, PDF, JPG, ... *anything*...

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

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

$crypt = new CkCrypt2();

// Load the cert and private key from separate files.
$cert = new CkCert();
$success = $cert->LoadFromFile('myCert.crt');
if ($success != true) {
    print $cert->lastErrorText() . "\n";
    exit;
}

$bd = new CkBinData();
$success = $bd->LoadFile('cert.key');
$privkey = new CkPrivateKey();
// Load from any format private key.
// If the file does not need a password, the 2nd arg is ignored.
$success = $privkey->LoadAnyFormat($bd,'password_if_needed');
if ($success != true) {
    print $privkey->lastErrorText() . "\n";
    exit;
}

$success = $crypt->SetSigningCert2($cert,$privkey);
if ($success != true) {
    print $crypt->lastErrorText() . "\n";
    exit;
}

// Create the opaque signature (PKCS7 binary DER that contains both the signature and original file data).
$success = $crypt->CreateP7M('qa_data/infile.anything','qa_output/outfile.der');
if ($success != true) {
    print $crypt->lastErrorText() . "\n";
    exit;
}

print 'Success.' . "\n";

?>