PHP

Enumerate Server-Advertised Acceptable Client CAs

Demonstrates Socket.GetSslAcceptableClientCaDn, which returns a certificate-authority distinguished name advertised by a TLS server when it requests a client certificate.

Background. Valid indexes range from 0 through NumSslAcceptableClientCAs minus one. A client can use these names to select an appropriate client certificate.

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Chilkat2 PHP

<?php

use Chilkat2\Socket;

$socket = new Socket();

// Connect to the server using TLS.
$bTls = true;
$maxWaitMs = 5000;
try {
    $socket->Connect('example.com', 5000, $bTls, $maxWaitMs);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

// After connecting to a server that requests a client certificate, enumerate the certificate-
// authority distinguished names the server advertised as acceptable.
$numCAs = $socket->NumSslAcceptableClientCAs;
for ($i = 0; $i < $numCAs; $i++) {
    try {
        $caDn = $socket->GetSslAcceptableClientCaDn($i);
    } catch (\Chilkat2\Exception $e) {
        echo $e->getMessage(), "\n";
        exit;
    }

    echo $caDn, "\n";
}