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<a name="Simple-client-example-in-C_002b_002b"></a>
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Next: <a href="Helper-functions-for-TCP-connections.html#Helper-functions-for-TCP-connections" accesskey="n" rel="next">Helper functions for TCP connections</a>, Previous: <a href="Simple-client-example-with-SRP-authentication.html#Simple-client-example-with-SRP-authentication" accesskey="p" rel="prev">Simple client example with SRP authentication</a>, Up: <a href="Client-examples.html#Client-examples" accesskey="u" rel="up">Client examples</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Function-and-Data-Index.html#Function-and-Data-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
<a name="Simple-client-example-using-the-C_002b_002b-API"></a>
<h4 class="subsection">7.1.11 Simple client example using the C++ API</h4>
<p>The following client is a simple example of a client client utilizing
the GnuTLS C++ API.
</p>
<pre class="verbatim">#include <config.h>
#include <iostream>
#include <stdexcept>
#include <gnutls/gnutls.h>
#include <gnutls/gnutlsxx.h>
#include <cstring> /* for strlen */
/* A very basic TLS client, with anonymous authentication.
* written by Eduardo Villanueva Che.
*/
#define MAX_BUF 1024
#define SA struct sockaddr
#define CAFILE "ca.pem"
#define MSG "GET / HTTP/1.0\r\n\r\n"
extern "C"
{
int tcp_connect(void);
void tcp_close(int sd);
}
int main(void)
{
int sd = -1;
gnutls_global_init();
try
{
/* Allow connections to servers that have OpenPGP keys as well.
*/
gnutls::client_session session;
/* X509 stuff */
gnutls::certificate_credentials credentials;
/* sets the trusted cas file
*/
credentials.set_x509_trust_file(CAFILE, GNUTLS_X509_FMT_PEM);
/* put the x509 credentials to the current session
*/
session.set_credentials(credentials);
/* Use default priorities */
session.set_priority ("NORMAL", NULL);
/* connect to the peer
*/
sd = tcp_connect();
session.set_transport_ptr((gnutls_transport_ptr_t) (ptrdiff_t)sd);
/* Perform the TLS handshake
*/
int ret = session.handshake();
if (ret < 0)
{
throw std::runtime_error("Handshake failed");
}
else
{
std::cout << "- Handshake was completed" << std::endl;
}
session.send(MSG, strlen(MSG));
char buffer[MAX_BUF + 1];
ret = session.recv(buffer, MAX_BUF);
if (ret == 0)
{
throw std::runtime_error("Peer has closed the TLS connection");
}
else if (ret < 0)
{
throw std::runtime_error(gnutls_strerror(ret));
}
std::cout << "- Received " << ret << " bytes:" << std::endl;
std::cout.write(buffer, ret);
std::cout << std::endl;
session.bye(GNUTLS_SHUT_RDWR);
}
catch (std::exception &ex)
{
std::cerr << "Exception caught: " << ex.what() << std::endl;
}
if (sd != -1)
tcp_close(sd);
gnutls_global_deinit();
return 0;
}
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