1 files changed, 92 insertions, 1 deletions

diff --git a/src/setup/gnunet-setup-options.c b/src/setup/gnunet-setup-options.c
index 35524a73..b35842c0 100644
--- a/src/setup/gnunet-setup-options.c
+++ b/src/setup/gnunet-setup-options.c
@@ -91,7 +91,7 @@ load_yes_no (const void *cls, const char *section, const char *option,
   GtkToggleButton *button;
 
   button = GTK_TOGGLE_BUTTON (widget);
-  if (button == NULL)
+  if (NULL == button)
     return GNUNET_SYSERR;
   gtk_toggle_button_set_active (button,
                                 (0 ==
@@ -101,6 +101,85 @@ load_yes_no (const void *cls, const char *section, const char *option,
 
 
 /**
+ * Initialize 'tcp_stealth' toggle button based on an options 'yes/no' value,
+ * make the widget sensitive if the platform supports TCP_STEALTH.
+ *
+ * @param cls closure
+ * @param section section with the value
+ * @param option option name
+ * @param value value as a string
+ * @param widget widget to initialize
+ * @param cfg configuration handle
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if there was a problem
+ */
+static int
+load_yes_no_check_tcp_stealth (const void *cls,
+                               const char *section,
+                               const char *option,
+                               const char *value,
+                               GObject * widget,
+                               const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  GtkWidget *button;
+  int ret;
+#ifdef SO_TCPSTEALTH
+  struct GNUNET_NETWORK_Handle *lsock;
+#endif
+  int disable;
+
+  ret = load_yes_no (cls, section,
+                     option, value,
+                     widget, cfg);
+  if (GNUNET_OK != ret)
+    return ret;
+  button = GTK_WIDGET (widget);
+  if (NULL == button)
+    return GNUNET_SYSERR;
+  /* check if TCP_STEALTH is supported by kernel */
+#ifdef SO_TCPSTEALTH
+  disable = GNUNET_NO;
+  lsock = GNUNET_NETWORK_socket_create (AF_INET, SOCK_STREAM, 0);
+  if (NULL == lsock)
+  {
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                         "socket");
+    return GNUNET_SYSERR;
+  }
+  else
+  {
+    if (GNUNET_OK !=
+        GNUNET_NETWORK_socket_setsockopt (lsock,
+                                          IPPROTO_TCP,
+                                          SO_TCPSTEALTH,
+                                          "test", 4))
+      disable = GNUNET_YES;
+    GNUNET_NETWORK_socket_close (lsock);
+  }
+#else
+  disable = GNUNET_YES;
+#endif
+  if (GNUNET_YES == disable)
+  {
+    /* force to false; with insensitive user could otherwise
+       not disable */
+    if (0 == strcasecmp (value, "YES"))
+    {
+      /* deactivate the option, but warn user, as this may open up
+         security issues */
+      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                  _("Disabling TCP STEALTH, not supported on this system.\n"));
+      gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (button),
+                                    FALSE);
+    }
+    return GNUNET_OK;
+  }
+  gtk_widget_set_sensitive (button,
+                            TRUE);
+  return GNUNET_OK;
+}
+
+
+/**
  * Set a yes/no option based on a toggle button.
  *
  * @param cls closure
@@ -1565,6 +1644,18 @@ const struct GNUNET_SETUP_OptionSpecification option_specifications[] = {
    NULL},
 
   {
+   "GNUNET_setup_transport_tcp_stealth_checkbutton",
+   "toggled",
+   "transport-tcp",
+   "TCP_STEALTH",
+   gettext_noop ("Should GNUnet use TCP STEALTH for the TCP server?"),
+   "https://gnunet.org/knock",
+   &load_yes_no_check_tcp_stealth,
+   &save_yes_no, NULL,
+   NULL, NULL,
+   NULL },
+
+  {
    "GNUNET_setup_transport_nat_checkbutton",
    "toggled",
    "nat",