Zig Requires Chilkat v11.0.0+

Examine Client Certificates for an Accepted TLS Connection

See more Socket/SSL/TLS Examples

Demonstrates how to access the client certificates for a TLS connection accepted by your application acting as the server. Zig

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

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

    const listen_ssl_socket = try chilkat.Socket.init();
    defer listen_ssl_socket.deinit();

    // An SSL/TLS server needs a digital certificate.  This example loads it from a PFX file.
    // This is the server's certificate.

    const cert = try chilkat.Cert.init();
    defer cert.deinit();
    cert.loadPfxFile("qa_data/serverCert/myServerCert.pfx", "pfx_password") catch {
        std.debug.print("{s}\n", .{try cert.getLastErrorText(alloc)});
        return;
    };

    // To accept client client certificates in the TLS handshake,
    // we must indicate a list of acceptable client certificate root CA DN's
    // that are allowed.  (DN is an acronym for Distinguished Name.)
    // Call AddSslAcceptableClientCaDn once for each acceptable CA DN.
    // Here are a few examples so you can see the general format of a DN.
    listen_ssl_socket.addSslAcceptableClientCaDn("C=SE, O=AddTrust AB, OU=AddTrust External TTP Network, CN=AddTrust External CA Root") catch {};
    listen_ssl_socket.addSslAcceptableClientCaDn("O=Digital Signature Trust Co., CN=DST Root CA X3") catch {};

    // Initialize with our server's TLS certificate.
    listen_ssl_socket.initSslServer(cert) catch {
        std.debug.print("{s}\n", .{try listen_ssl_socket.getLastErrorText(alloc)});
        return;
    };

    // Bind and listen on a port:
    const my_port = 8123;
    // Allow for a max of 5 queued connect requests.
    const back_log = 5;
    listen_ssl_socket.bindAndListen(my_port, back_log) catch {
        std.debug.print("{s}\n", .{try listen_ssl_socket.getLastErrorText(alloc)});
        return;
    };

    // Accept the next incoming connection.
    const max_wait_millisec = 20000;

    const client_sock = try chilkat.Socket.init();
    defer client_sock.deinit();
    listen_ssl_socket.acceptNext(max_wait_millisec, client_sock) catch {
        std.debug.print("{s}\n", .{try listen_ssl_socket.getLastErrorText(alloc)});
        return;
    };

    // Examine the client certs chain.  The 1st cert will be the client certificate, and
    // the subsequent certs will be the certs in the chain of authentication.
    const num_client_certs = client_sock.getNumReceivedClientCerts();
    std.debug.print("numClientCerts = {d}\n", .{num_client_certs});

    const client_cert = try chilkat.Cert.init();
    defer client_cert.deinit();
    var i: i32 = 0;
    while (i < num_client_certs) {
        client_sock.getRcvdClientCert(i, client_cert) catch {};
        std.debug.print("{s}\n", .{try client_cert.getSubjectDN(alloc)});
        i = i + 1;
    }

    // Close the connection with the client
    try client_sock.close(1000);
}