updated examples and added new "handling alerts" section.

1 files changed, 199 insertions, 0 deletions

diff --git a/doc/examples/ex-serv-x509.c b/doc/examples/ex-serv-x509.c
new file mode 100644
index 0000000000..5383fb3425
--- /dev/null
+++ b/doc/examples/ex-serv-x509.c
@@ -0,0 +1,199 @@
+/* This example code is placed in the public domain. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <unistd.h>
+#include <gnutls/gnutls.h>
+
+#define KEYFILE "key.pem"
+#define CERTFILE "cert.pem"
+#define CAFILE "ca.pem"
+#define CRLFILE "crl.pem"
+
+/* This is a sample TLS 1.0 echo server, using X.509 authentication.
+ */
+
+#define MAX_BUF 1024
+#define PORT 5556               /* listen to 5556 port */
+
+/* These are global */
+gnutls_certificate_credentials_t x509_cred;
+gnutls_priority_t priority_cache;
+
+static gnutls_session_t
+initialize_tls_session (void)
+{
+  gnutls_session_t session;
+
+  gnutls_init (&session, GNUTLS_SERVER);
+
+  gnutls_priority_set (session, priority_cache);
+
+  gnutls_credentials_set (session, GNUTLS_CRD_CERTIFICATE, x509_cred);
+
+  /* We don't request any certificate from the client.
+   * If we did we would need to verify it.
+   */
+  gnutls_certificate_server_set_request (session, GNUTLS_CERT_IGNORE);
+
+  return session;
+}
+
+static gnutls_dh_params_t dh_params;
+
+static int
+generate_dh_params (void)
+{
+  int bits = gnutls_sec_param_to_pk_bits (GNUTLS_PK_DH, GNUTLS_SEC_PARAM_LOW);
+
+  /* Generate Diffie-Hellman parameters - for use with DHE
+   * kx algorithms. When short bit length is used, it might
+   * be wise to regenerate parameters often.
+   */
+  gnutls_dh_params_init (&dh_params);
+  gnutls_dh_params_generate2 (dh_params, bits);
+
+  return 0;
+}
+
+int
+main (void)
+{
+  int listen_sd;
+  int sd, ret;
+  struct sockaddr_in sa_serv;
+  struct sockaddr_in sa_cli;
+  int client_len;
+  char topbuf[512];
+  gnutls_session_t session;
+  char buffer[MAX_BUF + 1];
+  int optval = 1;
+
+  /* this must be called once in the program
+   */
+  gnutls_global_init ();
+
+  gnutls_certificate_allocate_credentials (&x509_cred);
+  gnutls_certificate_set_x509_trust_file (x509_cred, CAFILE,
+                                          GNUTLS_X509_FMT_PEM);
+
+  gnutls_certificate_set_x509_crl_file (x509_cred, CRLFILE,
+                                        GNUTLS_X509_FMT_PEM);
+
+  ret = gnutls_certificate_set_x509_key_file (x509_cred, CERTFILE, KEYFILE,
+                                        GNUTLS_X509_FMT_PEM);
+  if (ret < 0)
+    {
+      printf("No certificate or key were found\n");
+      exit(1);
+    }
+
+  generate_dh_params ();
+
+  gnutls_priority_init (&priority_cache, "PERFORMANCE:%SERVER_PRECEDENCE", NULL);
+
+
+  gnutls_certificate_set_dh_params (x509_cred, dh_params);
+
+  /* Socket operations
+   */
+  listen_sd = socket (AF_INET, SOCK_STREAM, 0);
+
+  memset (&sa_serv, '\0', sizeof (sa_serv));
+  sa_serv.sin_family = AF_INET;
+  sa_serv.sin_addr.s_addr = INADDR_ANY;
+  sa_serv.sin_port = htons (PORT);      /* Server Port number */
+
+  setsockopt (listen_sd, SOL_SOCKET, SO_REUSEADDR, (void *) &optval,
+              sizeof (int));
+
+  bind (listen_sd, (struct sockaddr *) & sa_serv, sizeof (sa_serv));
+
+  listen (listen_sd, 1024);
+
+  printf ("Server ready. Listening to port '%d'.\n\n", PORT);
+
+  client_len = sizeof (sa_cli);
+  for (;;)
+    {
+      session = initialize_tls_session ();
+
+      sd = accept (listen_sd, (struct sockaddr *) & sa_cli, &client_len);
+
+      printf ("- connection from %s, port %d\n",
+              inet_ntop (AF_INET, &sa_cli.sin_addr, topbuf,
+                         sizeof (topbuf)), ntohs (sa_cli.sin_port));
+
+      gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
+
+      do
+        {
+          ret = gnutls_handshake (session);
+        }
+      while (gnutls_error_is_fatal (ret) == 0);
+
+      if (ret < 0)
+        {
+          close (sd);
+          gnutls_deinit (session);
+          fprintf (stderr, "*** Handshake has failed (%s)\n\n",
+                   gnutls_strerror (ret));
+          continue;
+        }
+      printf ("- Handshake was completed\n");
+
+      /* see the Getting peer's information example */
+      /* print_info(session); */
+
+      for (;;)
+        {
+          memset (buffer, 0, MAX_BUF + 1);
+          ret = gnutls_record_recv (session, buffer, MAX_BUF);
+
+          if (ret == 0)
+            {
+              printf ("\n- Peer has closed the GnuTLS connection\n");
+              break;
+            }
+          else if (ret < 0)
+            {
+              fprintf (stderr, "\n*** Received corrupted "
+                       "data(%d). Closing the connection.\n\n", ret);
+              break;
+            }
+          else if (ret > 0)
+            {
+              /* echo data back to the client
+               */
+              gnutls_record_send (session, buffer, strlen (buffer));
+            }
+        }
+      printf ("\n");
+      /* do not wait for the peer to close the connection.
+       */
+      gnutls_bye (session, GNUTLS_SHUT_WR);
+
+      close (sd);
+      gnutls_deinit (session);
+
+    }
+  close (listen_sd);
+
+  gnutls_certificate_free_credentials (x509_cred);
+  gnutls_priority_deinit (priority_cache);
+
+  gnutls_global_deinit ();
+
+  return 0;
+
+}