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/* This example code is placed in the public domain. */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <gnutls/gnutls.h>
/* Those functions are defined in other examples.
*/
extern void check_alert (gnutls_session_t session, int ret);
extern int tcp_connect (void);
extern void tcp_close (int sd);
#define MAX_BUF 1024
#define CAFILE "ca.pem"
#define MSG "GET / HTTP/1.0\r\n\r\n"
int
main (void)
{
int ret;
int sd, ii;
gnutls_session_t session;
char buffer[MAX_BUF + 1];
gnutls_certificate_credentials_t xcred;
/* variables used in session resuming
*/
int t;
char *session_data = NULL;
size_t session_data_size = 0;
gnutls_global_init ();
/* X509 stuff */
gnutls_certificate_allocate_credentials (&xcred);
gnutls_certificate_set_x509_trust_file (xcred, CAFILE, GNUTLS_X509_FMT_PEM);
for (t = 0; t < 2; t++)
{ /* connect 2 times to the server */
sd = tcp_connect ();
gnutls_init (&session, GNUTLS_CLIENT);
gnutls_priority_set_direct (session, "PERFORMANCE:!ARCFOUR-128", NULL);
gnutls_credentials_set (session, GNUTLS_CRD_CERTIFICATE, xcred);
if (t > 0)
{
/* if this is not the first time we connect */
gnutls_session_set_data (session, session_data, session_data_size);
free (session_data);
}
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
/* Perform the TLS handshake
*/
ret = gnutls_handshake (session);
if (ret < 0)
{
fprintf (stderr, "*** Handshake failed\n");
gnutls_perror (ret);
goto end;
}
else
{
printf ("- Handshake was completed\n");
}
if (t == 0)
{ /* the first time we connect */
/* get the session data size */
gnutls_session_get_data (session, NULL, &session_data_size);
session_data = malloc (session_data_size);
/* put session data to the session variable */
gnutls_session_get_data (session, session_data, &session_data_size);
}
else
{ /* the second time we connect */
/* check if we actually resumed the previous session */
if (gnutls_session_is_resumed (session) != 0)
{
printf ("- Previous session was resumed\n");
}
else
{
fprintf (stderr, "*** Previous session was NOT resumed\n");
}
}
/* This function was defined in a previous example
*/
/* print_info(session); */
gnutls_record_send (session, MSG, strlen (MSG));
ret = gnutls_record_recv (session, buffer, MAX_BUF);
if (ret == 0)
{
printf ("- Peer has closed the TLS connection\n");
goto end;
}
else if (ret < 0)
{
fprintf (stderr, "*** Error: %s\n", gnutls_strerror (ret));
goto end;
}
printf ("- Received %d bytes: ", ret);
for (ii = 0; ii < ret; ii++)
{
fputc (buffer[ii], stdout);
}
fputs ("\n", stdout);
gnutls_bye (session, GNUTLS_SHUT_RDWR);
end:
tcp_close (sd);
gnutls_deinit (session);
} /* for() */
gnutls_certificate_free_credentials (xcred);
gnutls_global_deinit ();
return 0;
}
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