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Perl

Enumerate Server-Advertised Acceptable Client CAs

See more Socket/SSL/TLS Examples

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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Perl
use chilkat();

$success = 0;

$socket = chilkat::CkSocket->new();

#  Connect to the server using TLS.
$bTls = 1;
$maxWaitMs = 5000;
$success = $socket->Connect("example.com",5000,$bTls,$maxWaitMs);
if ($success == 0) {
    print $socket->lastErrorText() . "\r\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->get_NumSslAcceptableClientCAs();

for ($i = 0; $i <= $numCAs - 1; $i++) {
    $caDn = $socket->getSslAcceptableClientCaDn($i);
    if ($socket->get_LastMethodSuccess() == 0) {
        print $socket->lastErrorText() . "\r\n";
        exit;
    }

    print $caDn . "\r\n";
}