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\begin{verbatim}
#include <stdio.h>
#include <stdlib.h>
#include <gnutls/gnutls.h>
#include <gnutls/extra.h>
/* Those functions are defined in other examples.
*/
extern void check_alert(gnutls_session session, int ret);
extern int tcp_connect( void);
void tcp_close( int sd);
#define MAX_BUF 1024
#define USERNAME "user"
#define PASSWORD "pass"
#define SA struct sockaddr
#define MSG "GET / HTTP/1.0\r\n\r\n"
const int kx_priority[] = { GNUTLS_KX_SRP, 0 };
int main()
{
int ret;
int sd, ii;
gnutls_session session;
char buffer[MAX_BUF + 1];
gnutls_srp_client_credentials xcred;
if (gnutls_global_init() < 0) {
fprintf(stderr, "global state initialization error\n");
exit(1);
}
/* now enable the gnutls-extra library which contains the
* SRP stuff. */
if (gnutls_global_init_extra() < 0) {
fprintf(stderr, "global state initialization error\n");
exit(1);
}
if (gnutls_srp_allocate_client_credentials(&xcred) < 0) {
fprintf(stderr, "memory error\n");
exit(1);
}
gnutls_srp_set_client_credentials(xcred, USERNAME, PASSWORD);
/* connects to server
*/
sd = tcp_connect();
/* Initialize TLS session
*/
gnutls_init(&session, GNUTLS_CLIENT);
/* Set the priorities.
*/
gnutls_set_default_priority(session);
gnutls_kx_set_priority(session, kx_priority);
/* put the SRP credentials to the current session
*/
gnutls_credentials_set(session, GNUTLS_CRD_SRP, xcred);
gnutls_transport_set_ptr( session, (gnutls_transport_ptr)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");
}
gnutls_record_send( session, MSG, strlen(MSG));
ret = gnutls_record_recv( session, buffer, MAX_BUF);
if (gnutls_error_is_fatal(ret) == 1 || ret == 0) {
if (ret == 0) {
printf("- Peer has closed the GNUTLS connection\n");
goto end;
} else {
fprintf(stderr, "*** Error: %s\n", gnutls_strerror(ret));
goto end;
}
} else
check_alert( session, ret);
if (ret > 0) {
printf("- Received %d bytes: ", ret);
for (ii = 0; ii < ret; ii++) {
fputc(buffer[ii], stdout);
}
fputs("\n", stdout);
}
gnutls_bye( session, 0);
end:
tcp_close( sd);
gnutls_deinit(session);
gnutls_srp_free_client_credentials(xcred);
gnutls_global_deinit();
return 0;
}
\end{verbatim}
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