PHP Requires Chilkat v11.0.0+
Generate a CSR with SAN (Subject Alternative Name) Extension

Demonstrates how to generate a private key and a Certificate Signing Request (CSR) that includes the SAN extension.
Chilkat PHP Downloads

Chilkat2 PHP
<?php

use Chilkat2\Csr;
use Chilkat2\FileAccess;
use Chilkat2\PrivateKey;
use Chilkat2\Rsa;

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

// First generate an RSA private key.
// (It is also possible to create CSRs based on ECDSA private keys..)
$rsa = new Rsa();

// Generate a random 2048-bit RSA key.
$privKey = new PrivateKey();
try {
    $rsa->GenKey(2048, $privKey);

    // Create the CSR object and set properties.
    $csr = new Csr();

    // Specify the Common Name.
    $csr->CommonName = 'mysubdomain.mydomain.com';

    // Country Name (2 letter code)
    $csr->Country = 'GB';

    // State or Province Name (full name)
    $csr->State = 'Yorks';

    // Locality Name (eg, city)
    $csr->Locality = 'York';

    // Organization Name (eg, company)
    $csr->Company = 'Internet Widgits Pty Ltd';

    // Organizational Unit Name (eg, secion/division)
    $csr->CompanyDivision = 'IT';

    // Email address
    $csr->EmailAddress = 'support@mydomain.com';

    // Add Subject Alternative Names
    // (The AddSan method is added in Chilkat v9.5.0.84)
    // Call AddSan for each alternative name.
    $csr->AddSan('dnsName', 'mydomain.com');
    $csr->AddSan('dnsName', 'mysubdomain.mydomain.com');
    $csr->AddSan('ipAddress', '192.168.0.123');

    // Create the CSR using the private key.
    $pemStr = $csr->GenCsrPem($privKey);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

// Save the private key and CSR to a files.
$privKey->SavePkcs8EncryptedPemFile('password', 'qa_output/privKey1.pem');

$fac = new FileAccess();
$fac->WriteEntireTextFile('qa_output/csr1.pem', $pemStr, 'utf-8', false);

// Show the CSR.
echo $pemStr, "\n";

// Sample output:

//     -----BEGIN CERTIFICATE REQUEST-----
//     MIIC6jCCAdICAQAwgaQxITAfBgNVBAMMGG15c3ViZG9tYWluLm15ZG9tYWluLmNv
//     bTELMAkGA1UEBhMCR0IxDjAMBgNVBAgMBVlvcmtzMQ0wCwYDVQQHDARZb3JrMSEw
//     HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQxCzAJBgNVBAsMAklUMSMw
//     IQYJKoZIhvcNAQkBFhRzdXBwb3J0QG15ZG9tYWluLmNvbTCCASIwDQYJKoZIhvcN
//     AQEBBQADggEPADCCAQoCggEBALnQ0un/wF8whk+gPuiAlf3qvx14jgAOV6Erm6EB
//     H7WACPCpnKcm/8KP+7uoPiwRQaENhMeCgf45vcivl2p6aAn/spLXyEkXyw2d8wFb
//     YYAGRkiz4Xf7ASJiKuwcOtORz+sSDzgtdfokHfXU1cYeFE2yQhSdLUY5fMn425+g
//     KoEEsRSjSDe6AKru4+4iGNrLKd8pB9IA5/jOE139IkWlB9r5fEPD5bUTsgqXk9eb
//     68O0gc712V2eZK07N24lDmFC4bIMTD4csDWocR5hFHXj7NX7c8sOBDcpEb9mPIk4
//     elxubnhkfnjhOi4J3lDHcT/0ALnbLhf9LnaiKqs+5VcVZvECAwEAAaAAMA0GCSqG
//     SIb3DQEBBQUAA4IBAQC0AETLIcP3foh5nbu2hVFS8uCUNZ5hEIR1eXmYZmZoBQq2
//     26ZAoT4CZwixlggC+n7WvAXJ5Pzxpl4wLV4loTiQzaKPX1w0ERo5ZRwLy0n56oG2
//     6QG+WTViT1C8rlgtVwkCFNOXr0kSSRs8FdaPllqKxK1hxYSL7zwNpumsk39F2cDt
//     vhcekvH0V3BuGrQFm3dKN/0azW6GOod9+Vq4VzSyOe3kp15oxLBsZOFOu/REujcw
//     Tzu2jt1asQKUm60CZ9wNHpYepR0Ww40uP1slbehEaFDa6V8b60/tlHHmBbJ4/fy5
//     hJnYCvjzFz4O9VtT+JtP9ldRHWV3KpZ8ne3AjD+F
//     -----END CERTIFICATE REQUEST-----