doc/examples/ex-client-srp.c

   1 /* This example code is placed in the public domain. */
   2
   3 #ifdef HAVE_CONFIG_H
   4 #include <config.h>
   5 #endif
   6
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10 #include <gnutls/gnutls.h>
  11
  12 /* Those functions are defined in other examples.
  13  */
  14 extern void check_alert (gnutls_session_t session, int ret);
  15 extern int tcp_connect (void);
  16 extern void tcp_close (int sd);
  17
  18 #define MAX_BUF 1024
  19 #define USERNAME "user"
  20 #define PASSWORD "pass"
  21 #define CAFILE "/etc/ssl/certs/ca-certificates.crt"
  22 #define MSG "GET / HTTP/1.0\r\n\r\n"
  23
  24 int
  25 main (void)
  26 {
  27   int ret;
  28   int sd, ii;
  29   gnutls_session_t session;
  30   char buffer[MAX_BUF + 1];
  31   gnutls_srp_client_credentials_t srp_cred;
  32   gnutls_certificate_credentials_t cert_cred;
  33
  34   gnutls_global_init ();
  35
  36   gnutls_srp_allocate_client_credentials (&srp_cred);
  37   gnutls_certificate_allocate_credentials (&cert_cred);
  38
  39   gnutls_certificate_set_x509_trust_file (cert_cred, CAFILE,
  40                                           GNUTLS_X509_FMT_PEM);
  41   gnutls_srp_set_client_credentials (srp_cred, USERNAME, PASSWORD);
  42
  43   /* connects to server
  44    */
  45   sd = tcp_connect ();
  46
  47   /* Initialize TLS session
  48    */
  49   gnutls_init (&session, GNUTLS_CLIENT);
  50
  51
  52   /* Set the priorities.
  53    */
  54   gnutls_priority_set_direct (session, "NORMAL:+SRP:+SRP-RSA:+SRP-DSS", NULL);
  55
  56   /* put the SRP credentials to the current session
  57    */
  58   gnutls_credentials_set (session, GNUTLS_CRD_SRP, srp_cred);
  59   gnutls_credentials_set (session, GNUTLS_CRD_CERTIFICATE, cert_cred);
  60
  61   gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
  62   gnutls_handshake_set_timeout (session, GNUTLS_DEFAULT_HANDSHAKE_TIMEOUT);
  63
  64   /* Perform the TLS handshake
  65    */
  66   do
  67     {
  68       ret = gnutls_handshake (session);
  69     }
  70   while (ret < 0 && gnutls_error_is_fatal (ret) == 0);
  71
  72   if (ret < 0)
  73     {
  74       fprintf (stderr, "*** Handshake failed\n");
  75       gnutls_perror (ret);
  76       goto end;
  77     }
  78   else
  79     {
  80       printf ("- Handshake was completed\n");
  81     }
  82
  83   gnutls_record_send (session, MSG, strlen (MSG));
  84
  85   ret = gnutls_record_recv (session, buffer, MAX_BUF);
  86   if (gnutls_error_is_fatal (ret) != 0 || ret == 0)
  87     {
  88       if (ret == 0)
  89         {
  90           printf ("- Peer has closed the GnuTLS connection\n");
  91           goto end;
  92         }
  93       else
  94         {
  95           fprintf (stderr, "*** Error: %s\n", gnutls_strerror (ret));
  96           goto end;
  97         }
  98     }
  99   else
 100     check_alert (session, ret);
 101
 102   if (ret > 0)
 103     {
 104       printf ("- Received %d bytes: ", ret);
 105       for (ii = 0; ii < ret; ii++)
 106         {
 107           fputc (buffer[ii], stdout);
 108         }
 109       fputs ("\n", stdout);
 110     }
 111   gnutls_bye (session, GNUTLS_SHUT_RDWR);
 112
 113 end:
 114
 115   tcp_close (sd);
 116
 117   gnutls_deinit (session);
 118
 119   gnutls_srp_free_client_credentials (srp_cred);
 120   gnutls_certificate_free_credentials (cert_cred);
 121
 122   gnutls_global_deinit ();
 123
 124   return 0;
 125 }