(PHP Extension) Duplicate openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

Demonstrates how to duplicate this OpenSSL command:

openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

1. Creates a SHA256 digest of the contents of the input file
2. Signs the SHA256 digest using the private key.

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux

<?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.

$pkey = new CkPrivateKey();

// Load the private key from an PEM file:
$success = $pkey->LoadPemFile('private.pem');
if ($success != true) {
    print $pkey->lastErrorText() . "\n";
    exit;
}

$rsa = new CkRsa();

// Import the private key into the RSA component:
$success = $rsa->ImportPrivateKeyObj($pkey);
if ($success != true) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

// OpenSSL uses big-endian.
$rsa->put_LittleEndian(false);

// Load the file to be signed.
$bdFileData = new CkBinData();
$success = $bdFileData->LoadFile('in.dat');

$bdSig = new CkBinData();
$success = $rsa->SignBd($bdFileData,'sha256',$bdSig);
if ($success != true) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

// Save the binary signature to a file.
$success = $bdSig->WriteFile('signature.sig');
if ($success != true) {
    print 'Failed to write signature.sig.' . "\n";
    exit;
}

print 'Success.' . "\n";

?>