(PHP Extension) RSA Signature using Private Key from .snk File

See more RSA Examples

A .snk file (Strong Name Key file) is a file format used in the .NET ecosystem to store an RSA public/private key pair. This key pair is typically used for strong-naming assemblies, which is a process of signing .NET assemblies to ensure their integrity and to uniquely identify them.

This example loads a private key from a .snk file and creates an RSA signature.

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<?php

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

$rsa = new CkRsa();

// Load the .snk and return the private key as XML.
$xmlStr = $rsa->snkToXml('./test.snk');
if ($rsa->get_LastMethodSuccess() == false) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

$success = $rsa->ImportPrivateKey($xmlStr);
if ($success == false) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

// Sign the SHA-256 hash of the utf-8 byte representation of the contents of sb
// Return the signature in base64 format.
$rsa->put_EncodingMode('base64');
$rsa->put_Charset('utf-8');
$sigBase64 = $rsa->signStringENC('This is the text to be hashed and signed.','sha256');
if ($rsa->get_LastMethodSuccess() == false) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

print 'RSA signature as base64: ' . $sigBase64 . "\n";

?>