(PHP Extension) RSA Sign with PKCS8 Encrypted Key

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature.

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<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

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

$pkey = new CkPrivateKey();

// Load the private key from an RSA PEM file:
$success = $pkey->LoadPkcs8EncryptedFile('privateKey.key','myPassword');

// Get the private key in XML format:
$pkeyXml = $pkey->getXml();

$rsa = new CkRsa();

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

// This example will sign a string, and receive the signature
// in a hex-encoded string.  Therefore, set the encoding mode
// to "hex":
$rsa->put_EncodingMode('hex');

// If some other non-Chilkat application or web service is going to be verifying
// the signature, it is important to match the byte-ordering.
// The LittleEndian property may be set to true
// for little-endian byte ordering, 
// or false  for big-endian byte ordering.
// Microsoft apps typically use little-endian, while
// OpenSSL and other services (such as Amazon CloudFront)
// use big-endian.
$rsa->put_LittleEndian(false);

$strData = 'This is the string to be signed.';

// Sign the string using the sha-1 hash algorithm.
// Other valid choices are "md2", "sha256", "sha384", "sha512",  and "md5".
$hexSig = $rsa->signStringENC($strData,'sha-1');

print $hexSig . "\n";

?>