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C++

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.

Chilkat C++ Downloads

C++
#include <CkSocket.h>
#include <CkCert.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkSocket listenSslSocket;

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

    CkCert cert;
    success = cert.LoadPfxFile("qa_data/serverCert/myServerCert.pfx","pfx_password");
    if (success == false) {
        std::cout << cert.lastErrorText() << "\r\n";
        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.
    listenSslSocket.AddSslAcceptableClientCaDn("C=SE, O=AddTrust AB, OU=AddTrust External TTP Network, CN=AddTrust External CA Root");
    listenSslSocket.AddSslAcceptableClientCaDn("O=Digital Signature Trust Co., CN=DST Root CA X3");

    // Initialize with our server's TLS certificate.
    success = listenSslSocket.InitSslServer(cert);
    if (success == false) {
        std::cout << listenSslSocket.lastErrorText() << "\r\n";
        return;
    }

    // Bind and listen on a port:
    int myPort = 8123;
    // Allow for a max of 5 queued connect requests.
    int backLog = 5;
    success = listenSslSocket.BindAndListen(myPort,backLog);
    if (success == false) {
        std::cout << listenSslSocket.lastErrorText() << "\r\n";
        return;
    }

    // Accept the next incoming connection.
    int maxWaitMillisec = 20000;

    CkSocket clientSock;
    success = listenSslSocket.AcceptNext(maxWaitMillisec,clientSock);
    if (success == false) {
        std::cout << listenSslSocket.lastErrorText() << "\r\n";
        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.
    int numClientCerts = clientSock.get_NumReceivedClientCerts();
    std::cout << "numClientCerts = " << numClientCerts << "\r\n";

    CkCert clientCert;
    int i = 0;
    while (i < numClientCerts) {
        clientSock.GetRcvdClientCert(i,clientCert);
        std::cout << clientCert.subjectDN() << "\r\n";
        i = i + 1;
    }

    // Close the connection with the client
    success = clientSock.Close(1000);
    }