@@ -1040,7 +1040,8 @@ process_ipv4_header (struct context *c, unsigned int flags, struct buffer *buf)

 	      if (flags & PIPV4_EXTRACT_DHCP_ROUTER)

 		{

 		  const in_addr_t dhcp_router = dhcp_extract_router_msg (&ipbuf);

-		  route_list_add_default_gateway (c->c1.route_list, c->c2.es, dhcp_router);

+		  if (dhcp_router)

+		    route_list_add_default_gateway (c->c1.route_list, c->c2.es, dhcp_router);

 		}

 	    }

 	}

@@ -2780,6 +2780,14 @@ positive_atoi (const char *str)

   return i < 0 ? 0 : i;

 }

+static unsigned int

+atou (const char *str)

+{

+  unsigned int val = 0;

+  sscanf (str, "%u", &val);

+  return val;

+}

+

 static inline bool

 space (unsigned char c)

 {

@@ -5097,6 +5105,19 @@ add_option (struct options *options,

       VERIFY_PERMISSION (OPT_P_IPWIN32);

       options->tuntap_options.dhcp_release = true;

     }

+  else if (streq (p[0], "dhcp-rr") && p[1]) /* standalone method for internal use */

+    {

+      unsigned int adapter_index;

+      VERIFY_PERMISSION (OPT_P_GENERAL);

+      set_debug_level (options->verbosity, SDL_CONSTRAIN);

+      adapter_index = atou (p[1]);

+      sleep (options->tuntap_options.tap_sleep);

+      if (options->tuntap_options.dhcp_pre_release)

+	dhcp_release_by_adapter_index (adapter_index);

+      if (options->tuntap_options.dhcp_renew)

+	dhcp_renew_by_adapter_index (adapter_index);

+      openvpn_exit (OPENVPN_EXIT_STATUS_USAGE); /* exit point */

+    }

   else if (streq (p[0], "show-valid-subnets"))

     {

       VERIFY_PERMISSION (OPT_P_GENERAL);

@@ -3292,59 +3292,73 @@ tap_allow_nonadmin_access (const char *dev_node)

 /*

  * DHCP release/renewal

  */

-

 bool

-dhcp_release (const struct tuntap *tt)

+dhcp_release_by_adapter_index(const DWORD adapter_index)

 {

   struct gc_arena gc = gc_new ();

   bool ret = false;

-  if (tt && tt->options.ip_win32_type == IPW32_SET_DHCP_MASQ && tt->adapter_index != ~0)

+  const IP_ADAPTER_INDEX_MAP *inter = get_interface_info (adapter_index, &gc);

+

+  if (inter)

     {

-      const IP_ADAPTER_INDEX_MAP *inter = get_interface_info (tt->adapter_index, &gc);

-      if (inter)

+      DWORD status = IpReleaseAddress ((IP_ADAPTER_INDEX_MAP *)inter);

+      if (status == NO_ERROR)

 	{

-	  DWORD status = IpReleaseAddress ((IP_ADAPTER_INDEX_MAP *)inter);

-	  if (status == NO_ERROR)

-	    {

-	      msg (D_TUNTAP_INFO, "TAP: DHCP address released");

-	      ret = true;

-	    }

-	  else

-	    msg (M_WARN, "NOTE: Release of DHCP-assigned IP address lease on TAP-Win32 adapter failed: %s (code=%u)",

-		 strerror_win32 (status, &gc),

-		 (unsigned int)status);

+	  msg (D_TUNTAP_INFO, "TAP: DHCP address released");

+	  ret = true;

 	}

+      else

+	msg (M_WARN, "NOTE: Release of DHCP-assigned IP address lease on TAP-Win32 adapter failed: %s (code=%u)",

+	     strerror_win32 (status, &gc),

+	     (unsigned int)status);

     }

+

   gc_free (&gc);

   return ret;

 }

+static bool

+dhcp_release (const struct tuntap *tt)

+{

+  if (tt && tt->options.ip_win32_type == IPW32_SET_DHCP_MASQ && tt->adapter_index != ~0)

+    return dhcp_release_by_adapter_index (tt->adapter_index);

+  else

+    return false;

+}

+

 bool

-dhcp_renew (const struct tuntap *tt)

+dhcp_renew_by_adapter_index (const DWORD adapter_index)

 {

   struct gc_arena gc = gc_new ();

   bool ret = false;

-  if (tt && tt->options.ip_win32_type == IPW32_SET_DHCP_MASQ && tt->adapter_index != ~0)

+  const IP_ADAPTER_INDEX_MAP *inter = get_interface_info (adapter_index, &gc);

+

+  if (inter)

     {

-      const IP_ADAPTER_INDEX_MAP *inter = get_interface_info (tt->adapter_index, &gc);

-      if (inter)

+      DWORD status = IpRenewAddress ((IP_ADAPTER_INDEX_MAP *)inter);

+      if (status == NO_ERROR)

 	{

-	  DWORD status = IpRenewAddress ((IP_ADAPTER_INDEX_MAP *)inter);

-	  if (status == NO_ERROR)

-	    {

-	      msg (D_TUNTAP_INFO, "TAP: DHCP address renewal succeeded");

-	      ret = true;

-	    }

-	  else

-	    msg (M_WARN, "WARNING: Failed to renew DHCP IP address lease on TAP-Win32 adapter: %s (code=%u)",

-		 strerror_win32 (status, &gc),

-		 (unsigned int)status);

+	  msg (D_TUNTAP_INFO, "TAP: DHCP address renewal succeeded");

+	  ret = true;

 	}

+      else

+	msg (M_WARN, "WARNING: Failed to renew DHCP IP address lease on TAP-Win32 adapter: %s (code=%u)",

+	     strerror_win32 (status, &gc),

+	     (unsigned int)status);

     }

   gc_free (&gc);

   return ret;

 }

+static bool

+dhcp_renew (const struct tuntap *tt)

+{

+  if (tt && tt->options.ip_win32_type == IPW32_SET_DHCP_MASQ && tt->adapter_index != ~0)

+    return dhcp_renew_by_adapter_index (tt->adapter_index);

+  else

+    return false;

+}

+

 /*

  * netsh functions

  */

@@ -3788,6 +3802,28 @@ build_dhcp_options_string (struct buffer *buf, const struct tuntap_options *o)

   return !error;

 }

+static void

+fork_dhcp_action (struct tuntap *tt)

+{

+  if (tt->options.dhcp_pre_release || tt->options.dhcp_renew)

+    {

+      struct gc_arena gc = gc_new ();

+      struct buffer cmd = alloc_buf_gc (256, &gc);

+      const int verb = 3;

+      const int pre_sleep = 1;

+  

+      buf_printf (&cmd, "openvpn --verb %d --tap-sleep %d", verb, pre_sleep);

+      if (tt->options.dhcp_pre_release)

+	buf_printf (&cmd, " --dhcp-pre-release");

+      if (tt->options.dhcp_renew)

+	buf_printf (&cmd, " --dhcp-renew");

+      buf_printf (&cmd, " --dhcp-rr %u", (unsigned int)tt->adapter_index);

+

+      fork_to_self (BSTR (&cmd));

+      gc_free (&gc);

+    }

+}

+

 void

 open_tun (const char *dev, const char *dev_type, const char *dev_node, bool ipv6, struct tuntap *tt)

 {

@@ -4152,6 +4188,8 @@ open_tun (const char *dev, const char *dev_type, const char *dev_node, bool ipv6

 	if (tt->options.dhcp_renew)

 	  dhcp_renew (tt);

       }

+    else

+      fork_dhcp_action (tt);

     if (tt->did_ifconfig_setup && tt->options.ip_win32_type == IPW32_SET_IPAPI)

       {

@@ -332,8 +332,8 @@ void show_valid_win32_tun_subnets (void);

 const char *tap_win32_getinfo (const struct tuntap *tt, struct gc_arena *gc);

 void tun_show_debug (struct tuntap *tt);

-bool dhcp_release (const struct tuntap *tt);

-bool dhcp_renew (const struct tuntap *tt);

+bool dhcp_release_by_adapter_index(const DWORD adapter_index);

+bool dhcp_renew_by_adapter_index (const DWORD adapter_index);

 void tun_standby_init (struct tuntap *tt);

 bool tun_standby (struct tuntap *tt);

@@ -1,5 +1,5 @@

 dnl define the OpenVPN version

-define(PRODUCT_VERSION,[2.1_rc21a])

+define(PRODUCT_VERSION,[2.1_rc21b])

 dnl define the TAP version

 define(PRODUCT_TAP_ID,[tap0901])

 define(PRODUCT_TAP_WIN32_MIN_MAJOR,[9])

@@ -1016,6 +1016,51 @@ openvpn_execve (const struct argv *a, const struct env_set *es, const unsigned i

   return ret;

 }

+/*

+ * call ourself in another process

+ */

+void

+fork_to_self (const char *cmdline)

+{

+  STARTUPINFO start_info;

+  PROCESS_INFORMATION proc_info;

+  char self_exe[256];

+  char *cl = string_alloc (cmdline, NULL);

+  DWORD status;

+

+  CLEAR (start_info);

+  CLEAR (proc_info);

+  CLEAR (self_exe);

+

+  status = GetModuleFileName (NULL, self_exe, sizeof(self_exe));

+  if (status == 0 || status == sizeof(self_exe))

+    {

+      msg (M_WARN|M_ERRNO, "fork_to_self: CreateProcess failed: cannot get module name via GetModuleFileName");

+      goto done;

+    }

+

+  /* fill in STARTUPINFO struct */

+  GetStartupInfo(&start_info);

+  start_info.cb = sizeof(start_info);

+  start_info.dwFlags = STARTF_USESTDHANDLES|STARTF_USESHOWWINDOW;

+  start_info.wShowWindow = SW_HIDE;

+  start_info.hStdInput = GetStdHandle(STD_INPUT_HANDLE);

+  start_info.hStdOutput = start_info.hStdError = GetStdHandle(STD_OUTPUT_HANDLE);

+

+  if (CreateProcess (self_exe, cl, NULL, NULL, FALSE, 0, NULL, NULL, &start_info, &proc_info))

+    {

+      CloseHandle (proc_info.hThread);

+      CloseHandle (proc_info.hProcess);

+    }

+  else

+    {

+      msg (M_WARN|M_ERRNO, "fork_to_self: CreateProcess failed: %s", cmdline);

+    }

+

+ done:

+  free (cl);

+}

+

 char *

 get_win_sys_path (void)

 {

@@ -265,5 +265,8 @@ void set_win_sys_path (const char *newpath, struct env_set *es);

 void set_win_sys_path_via_env (struct env_set *es);

 char *get_win_sys_path (void);

+/* call self in a subprocess */

+void fork_to_self (const char *cmdline);

+

 #endif

 #endif