/*
  *  OpenVPN -- An application to securely tunnel IP networks
  *             over a single TCP/UDP port, with support for SSL/TLS-based
  *             session authentication and key exchange,
  *             packet encryption, packet authentication, and
  *             packet compression.
  *

  *  Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>

  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2
  *  as published by the Free Software Foundation.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program (see the file COPYING included with this
  *  distribution); if not, write to the Free Software Foundation, Inc.,
  *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
 /*
  * Support routines for adding/deleting network routes.
  */
 
 #include "syshead.h"
 
 #include "common.h"
 #include "error.h"
 #include "route.h"
 #include "misc.h"
 #include "socket.h"
 #include "manage.h"

 #include "win32.h"

 
 #include "memdbg.h"
 
 static void delete_route (const struct route *r, const struct tuntap *tt, unsigned int flags, const struct env_set *es);

 static void get_bypass_addresses (struct route_bypass *rb, const unsigned int flags);
 
 #ifdef ENABLE_DEBUG
 
 static void
 print_bypass_addresses (const struct route_bypass *rb)
 {
   struct gc_arena gc = gc_new ();
   int i;
   for (i = 0; i < rb->n_bypass; ++i)
     {

       msg (D_ROUTE, "ROUTE: bypass_host_route[%d]=%s",

 	   i,
 	   print_in_addr_t (rb->bypass[i], 0, &gc));
     }
   gc_free (&gc);
 }
 
 #endif
 
 static bool
 add_bypass_address (struct route_bypass *rb, const in_addr_t a)
 {
   int i;
   for (i = 0; i < rb->n_bypass; ++i)
     {
       if (a == rb->bypass[i]) /* avoid duplicates */
 	return true;
     }
   if (rb->n_bypass < N_ROUTE_BYPASS)
     {
       rb->bypass[rb->n_bypass++] = a;
       return true;
     }
   else
     {
       return false;
     }
 }

 
 struct route_option_list *

 new_route_option_list (const int max_routes, struct gc_arena *a)

 {
   struct route_option_list *ret;

   ALLOC_VAR_ARRAY_CLEAR_GC (ret, struct route_option_list, struct route_option, max_routes, a);
   ret->capacity = max_routes;

   return ret;
 }
 

 struct route_option_list *
 clone_route_option_list (const struct route_option_list *src, struct gc_arena *a)
 {
   const size_t rl_size = array_mult_safe (sizeof(struct route_option), src->capacity, sizeof(struct route_option_list));
   struct route_option_list *ret = gc_malloc (rl_size, false, a);
   memcpy (ret, src, rl_size);
   return ret;
 }
 
 void
 copy_route_option_list (struct route_option_list *dest, const struct route_option_list *src)
 {
   const size_t src_size = array_mult_safe (sizeof(struct route_option), src->capacity, sizeof(struct route_option_list));
   if (src->n > dest->capacity)
     msg (M_FATAL, PACKAGE_NAME " ROUTE: (copy) number of route options in src (%d) is greater than route list capacity in dest (%d)", src->n, dest->capacity);
   memcpy (dest, src, src_size);
 }
 

 struct route_list *

 new_route_list (const int max_routes, struct gc_arena *a)

 {
   struct route_list *ret;

   ALLOC_VAR_ARRAY_CLEAR_GC (ret, struct route_list, struct route, max_routes, a);
   ret->capacity = max_routes;

   return ret;
 }
 
 static const char *
 route_string (const struct route *r, struct gc_arena *gc)
 {
   struct buffer out = alloc_buf_gc (256, gc);
   buf_printf (&out, "ROUTE network %s netmask %s gateway %s",
 	      print_in_addr_t (r->network, 0, gc),
 	      print_in_addr_t (r->netmask, 0, gc),
 	      print_in_addr_t (r->gateway, 0, gc)
 	      );
   if (r->metric_defined)
     buf_printf (&out, " metric %d", r->metric);
   return BSTR (&out);
 }
 
 static bool
 is_route_parm_defined (const char *parm)
 {
   if (!parm)
     return false;
   if (!strcmp (parm, "default"))
     return false;
   return true;
 }
 
 static void
 setenv_route_addr (struct env_set *es, const char *key, const in_addr_t addr, int i)
 {
   struct gc_arena gc = gc_new ();
   struct buffer name = alloc_buf_gc (256, &gc);
   if (i >= 0)
     buf_printf (&name, "route_%s_%d", key, i);
   else
     buf_printf (&name, "route_%s", key);
   setenv_str (es, BSTR (&name), print_in_addr_t (addr, 0, &gc));
   gc_free (&gc);
 }
 
 static bool
 get_special_addr (const struct route_special_addr *spec,
 		  const char *string,
 		  in_addr_t *out,
 		  bool *status)
 {

   if (status)
     *status = true;

   if (!strcmp (string, "vpn_gateway"))
     {

       if (spec)

 	{

 	  if (spec->remote_endpoint_defined)
 	    *out = spec->remote_endpoint;
 	  else
 	    {
 	      msg (M_INFO, PACKAGE_NAME " ROUTE: vpn_gateway undefined");
 	      if (status)
 		*status = false;
 	    }

 	}
       return true;
     }
   else if (!strcmp (string, "net_gateway"))
     {

       if (spec)

 	{

 	  if (spec->net_gateway_defined)
 	    *out = spec->net_gateway;
 	  else
 	    {
 	      msg (M_INFO, PACKAGE_NAME " ROUTE: net_gateway undefined -- unable to get default gateway from system");
 	      if (status)
 		*status = false;
 	    }

 	}
       return true;
     }
   else if (!strcmp (string, "remote_host"))
     {

       if (spec)

 	{

 	  if (spec->remote_host_defined)
 	    *out = spec->remote_host;
 	  else
 	    {
 	      msg (M_INFO, PACKAGE_NAME " ROUTE: remote_host undefined");
 	      if (status)
 		*status = false;
 	    }

 	}
       return true;
     }
   return false;
 }
 

 bool
 is_special_addr (const char *addr_str)
 {
   if (addr_str)
     return get_special_addr (NULL, addr_str, NULL, NULL);
   else
     return false;
 }
 

 static bool
 init_route (struct route *r,

 	    struct resolve_list *network_list,

 	    const struct route_option *ro,
 	    const struct route_special_addr *spec)
 {
   const in_addr_t default_netmask = ~0;
   bool status;
 
   r->option = ro;
   r->defined = false;
 
   /* network */
 
   if (!is_route_parm_defined (ro->network))
     {
       goto fail;
     }
   
   if (!get_special_addr (spec, ro->network, &r->network, &status))
     {

       r->network = getaddr_multi (
 				  GETADDR_RESOLVE
 				  | GETADDR_HOST_ORDER
 				  | GETADDR_WARN_ON_SIGNAL,
 				  ro->network,
 				  0,
 				  &status,
 				  NULL,
 				  network_list);

     }
 
   if (!status)
     goto fail;
 
   /* netmask */
 
   if (is_route_parm_defined (ro->netmask))
     {
       r->netmask = getaddr (
 			    GETADDR_HOST_ORDER
 			    | GETADDR_WARN_ON_SIGNAL,
 			    ro->netmask,
 			    0,
 			    &status,
 			    NULL);
       if (!status)
 	goto fail;
     }
   else
     r->netmask = default_netmask;
 
   /* gateway */
 
   if (is_route_parm_defined (ro->gateway))
     {
       if (!get_special_addr (spec, ro->gateway, &r->gateway, &status))
 	{
 	  r->gateway = getaddr (
 				GETADDR_RESOLVE
 				| GETADDR_HOST_ORDER
 				| GETADDR_WARN_ON_SIGNAL,
 				ro->gateway,
 				0,
 				&status,
 				NULL);
 	}
       if (!status)
 	goto fail;
     }
   else
     {
       if (spec->remote_endpoint_defined)
 	r->gateway = spec->remote_endpoint;
       else
 	{
 	  msg (M_WARN, PACKAGE_NAME " ROUTE: " PACKAGE_NAME " needs a gateway parameter for a --route option and no default was specified by either --route-gateway or --ifconfig options");
 	  goto fail;
 	}
     }
 
   /* metric */
 
   r->metric_defined = false;
   r->metric = 0;
   if (is_route_parm_defined (ro->metric))
     {
       r->metric = atoi (ro->metric);
       if (r->metric < 0)
 	{
 	  msg (M_WARN, PACKAGE_NAME " ROUTE: route metric for network %s (%s) must be >= 0",
 	       ro->network,
 	       ro->metric);
 	  goto fail;
 	}
       r->metric_defined = true;
     }

   else if (spec->default_metric_defined)

     {

       r->metric = spec->default_metric;
       r->metric_defined = true;

     }
 
   r->defined = true;
 
   return true;
 
  fail:
   msg (M_WARN, PACKAGE_NAME " ROUTE: failed to parse/resolve route for host/network: %s",
        ro->network);
   r->defined = false;
   return false;
 }
 
 void
 add_route_to_option_list (struct route_option_list *l,
 			  const char *network,
 			  const char *netmask,
 			  const char *gateway,
 			  const char *metric)
 {
   struct route_option *ro;

   if (l->n >= l->capacity)
     msg (M_FATAL, PACKAGE_NAME " ROUTE: cannot add more than %d routes -- please increase the max-routes option in the client configuration file",
 	 l->capacity);

   ro = &l->routes[l->n];
   ro->network = network;
   ro->netmask = netmask;
   ro->gateway = gateway;
   ro->metric = metric;
   ++l->n;
 }
 
 void
 clear_route_list (struct route_list *rl)
 {

   const int capacity = rl->capacity;
   const size_t rl_size = array_mult_safe (sizeof(struct route), capacity, sizeof(struct route_list));
   memset(rl, 0, rl_size);
   rl->capacity = capacity;

 }
 

 void
 route_list_add_default_gateway (struct route_list *rl,
 				struct env_set *es,
 				const in_addr_t addr)
 {
   rl->spec.remote_endpoint = addr;
   rl->spec.remote_endpoint_defined = true;
   setenv_route_addr (es, "vpn_gateway", rl->spec.remote_endpoint, -1);
 }
 

 bool
 init_route_list (struct route_list *rl,
 		 const struct route_option_list *opt,
 		 const char *remote_endpoint,

 		 int default_metric,

 		 in_addr_t remote_host,
 		 struct env_set *es)
 {

   struct gc_arena gc = gc_new ();

   bool ret = true;
 
   clear_route_list (rl);
 

   rl->flags = opt->flags;
 

   if (remote_host)
     {
       rl->spec.remote_host = remote_host;
       rl->spec.remote_host_defined = true;
     }
 

   if (default_metric)
     {
       rl->spec.default_metric = default_metric;
       rl->spec.default_metric_defined = true;
     }
 

   rl->spec.net_gateway_defined = get_default_gateway (&rl->spec.net_gateway, NULL);

   if (rl->spec.net_gateway_defined)
     {
       setenv_route_addr (es, "net_gateway", rl->spec.net_gateway, -1);

       dmsg (D_ROUTE, "ROUTE default_gateway=%s", print_in_addr_t (rl->spec.net_gateway, 0, &gc));

     }

   else
     {

       dmsg (D_ROUTE, "ROUTE: default_gateway=UNDEF");

     }

 
   if (rl->flags & RG_ENABLE)
     {
       get_bypass_addresses (&rl->spec.bypass, rl->flags);
 #ifdef ENABLE_DEBUG
       print_bypass_addresses (&rl->spec.bypass);
 #endif

     }
 
   if (is_route_parm_defined (remote_endpoint))
     {
       rl->spec.remote_endpoint = getaddr (
 				     GETADDR_RESOLVE
 				     | GETADDR_HOST_ORDER
 				     | GETADDR_WARN_ON_SIGNAL,
 				     remote_endpoint,
 				     0,
 				     &rl->spec.remote_endpoint_defined,
 				     NULL);
 
       if (rl->spec.remote_endpoint_defined)
 	{
 	  setenv_route_addr (es, "vpn_gateway", rl->spec.remote_endpoint, -1);
 	}
       else
 	{
 	  msg (M_WARN, PACKAGE_NAME " ROUTE: failed to parse/resolve default gateway: %s",
 	       remote_endpoint);
 	  ret = false;
 	}
     }
   else
     rl->spec.remote_endpoint_defined = false;
 
   /* parse the routes from opt to rl */
   {
     int i, j = 0;

     bool warned = false;

     for (i = 0; i < opt->n; ++i)
       {

 	struct resolve_list netlist;
 	struct route r;
 	int k;
 
 	if (!init_route (&r,
 			 &netlist,

 			 &opt->routes[i],
 			 &rl->spec))
 	  ret = false;
 	else

 	  {
 	    if (!netlist.len)
 	      {
 		netlist.data[0] = r.network;
 		netlist.len = 1;
 	      }
 	    for (k = 0; k < netlist.len; ++k)
 	      {
 		if (j < rl->capacity)
 		  {
 		    r.network = netlist.data[k];
 		    rl->routes[j++] = r;
 		  }
 		else
 		  {
 		    if (!warned)
 		      {
 			msg (M_WARN, PACKAGE_NAME " ROUTE: routes dropped because number of expanded routes is greater than route list capacity (%d)", rl->capacity);
 			warned = true;
 		      }
 		  }
 	      }
 	  }

       }
     rl->n = j;
   }
 

   gc_free (&gc);

   return ret;
 }
 
 static void
 add_route3 (in_addr_t network,
 	    in_addr_t netmask,
 	    in_addr_t gateway,
 	    const struct tuntap *tt,
 	    unsigned int flags,
 	    const struct env_set *es)
 {
   struct route r;
   CLEAR (r);
   r.defined = true;
   r.network = network;
   r.netmask = netmask;
   r.gateway = gateway;
   add_route (&r, tt, flags, es);
 }
 
 static void
 del_route3 (in_addr_t network,
 	    in_addr_t netmask,
 	    in_addr_t gateway,
 	    const struct tuntap *tt,
 	    unsigned int flags,
 	    const struct env_set *es)
 {
   struct route r;
   CLEAR (r);
   r.defined = true;
   r.network = network;
   r.netmask = netmask;
   r.gateway = gateway;
   delete_route (&r, tt, flags, es);
 }
 
 static void

 add_bypass_routes (struct route_bypass *rb,
 		   in_addr_t gateway,
 		   const struct tuntap *tt,
 		   unsigned int flags,
 		   const struct env_set *es)
 {
   int i;
   for (i = 0; i < rb->n_bypass; ++i)
     {
       if (rb->bypass[i] != gateway)
 	add_route3 (rb->bypass[i],
 		    ~0,
 		    gateway,
 		    tt,
 		    flags,
 		    es);
     }
 }
 
 static void
 del_bypass_routes (struct route_bypass *rb,
 		   in_addr_t gateway,
 		   const struct tuntap *tt,
 		   unsigned int flags,
 		   const struct env_set *es)
 {
   int i;
   for (i = 0; i < rb->n_bypass; ++i)
     {
       if (rb->bypass[i] != gateway)
 	del_route3 (rb->bypass[i],
 		    ~0,
 		    gateway,
 		    tt,
 		    flags,
 		    es);
     }
 }
 
 static void

 redirect_default_route_to_vpn (struct route_list *rl, const struct tuntap *tt, unsigned int flags, const struct env_set *es)
 {
   const char err[] = "NOTE: unable to redirect default gateway --";
 

   if (rl->flags & RG_ENABLE)

     {
       if (!rl->spec.remote_endpoint_defined)
 	{
 	  msg (M_WARN, "%s VPN gateway parameter (--route-gateway or --ifconfig) is missing", err);
 	}
       else if (!rl->spec.net_gateway_defined)
 	{
 	  msg (M_WARN, "%s Cannot read current default gateway from system", err);
 	}
       else if (!rl->spec.remote_host_defined)
 	{
 	  msg (M_WARN, "%s Cannot obtain current remote host address", err);
 	}
       else
 	{

 	  bool local = BOOL_CAST(rl->flags & RG_LOCAL);
 	  if (rl->flags & RG_AUTO_LOCAL) {
 	    const int tla = test_local_addr (rl->spec.remote_host);
 	    if (tla == TLA_NONLOCAL)
 	      {
 		dmsg (D_ROUTE, "ROUTE remote_host is NOT LOCAL");
 		local = false;
 	      }
 	    else if (tla == TLA_LOCAL)
 	      {
 		dmsg (D_ROUTE, "ROUTE remote_host is LOCAL");
 		local = true;
 	      }
 	  }
 	  if (!local)
 	    {
 	      /* route remote host to original default gateway */
 	      add_route3 (rl->spec.remote_host,
 			  ~0,
 			  rl->spec.net_gateway,
 			  tt,
 			  flags,
 			  es);
 	      rl->did_local = true;
 	    }

 	  /* route DHCP/DNS server traffic through original default gateway */
 	  add_bypass_routes (&rl->spec.bypass, rl->spec.net_gateway, tt, flags, es);
 

 	  if (rl->flags & RG_REROUTE_GW)
 	    {
 	      if (rl->flags & RG_DEF1)
 		{
 		  /* add new default route (1st component) */
 		  add_route3 (0x00000000,
 			      0x80000000,
 			      rl->spec.remote_endpoint,
 			      tt,
 			      flags,
 			      es);
 
 		  /* add new default route (2nd component) */
 		  add_route3 (0x80000000,
 			      0x80000000,
 			      rl->spec.remote_endpoint,
 			      tt,
 			      flags,
 			      es);
 		}
 	      else
 		{
 		  /* delete default route */
 		  del_route3 (0,
 			      0,
 			      rl->spec.net_gateway,
 			      tt,
 			      flags,
 			      es);
 
 		  /* add new default route */
 		  add_route3 (0,
 			      0,
 			      rl->spec.remote_endpoint,
 			      tt,
 			      flags,
 			      es);
 		}
 	    }
 
 	  /* set a flag so we can undo later */
 	  rl->did_redirect_default_gateway = true;
 	}
     }
 }
 
 static void
 undo_redirect_default_route_to_vpn (struct route_list *rl, const struct tuntap *tt, unsigned int flags, const struct env_set *es)
 {
   if (rl->did_redirect_default_gateway)
     {
       /* delete remote host route */

       if (rl->did_local)
 	{
 	  del_route3 (rl->spec.remote_host,
 		      ~0,
 		      rl->spec.net_gateway,
 		      tt,
 		      flags,
 		      es);
 	  rl->did_local = false;
 	}

 
       /* delete special DHCP/DNS bypass route */
       del_bypass_routes (&rl->spec.bypass, rl->spec.net_gateway, tt, flags, es);
 
       if (rl->flags & RG_REROUTE_GW)
 	{

 	  if (rl->flags & RG_DEF1)

 	    {

 	      /* delete default route (1st component) */
 	      del_route3 (0x00000000,

 			  0x80000000,
 			  rl->spec.remote_endpoint,
 			  tt,
 			  flags,
 			  es);
 

 	      /* delete default route (2nd component) */
 	      del_route3 (0x80000000,

 			  0x80000000,
 			  rl->spec.remote_endpoint,
 			  tt,
 			  flags,
 			  es);
 	    }
 	  else
 	    {
 	      /* delete default route */
 	      del_route3 (0,
 			  0,

 			  rl->spec.remote_endpoint,

 			  tt,
 			  flags,
 			  es);
 

 	      /* restore original default route */

 	      add_route3 (0,
 			  0,

 			  rl->spec.net_gateway,

 			  tt,
 			  flags,
 			  es);
 	    }
 	}
 
       rl->did_redirect_default_gateway = false;
     }
 }
 
 void
 add_routes (struct route_list *rl, const struct tuntap *tt, unsigned int flags, const struct env_set *es)
 {
   redirect_default_route_to_vpn (rl, tt, flags, es);
   if (!rl->routes_added)
     {
       int i;
 
 #ifdef ENABLE_MANAGEMENT
       if (management && rl->n)
 	{
 	  management_set_state (management,
 				OPENVPN_STATE_ADD_ROUTES,
 				NULL,

 				0,

 				0);
 	}
 #endif
       
       for (i = 0; i < rl->n; ++i)
 	{

 	  struct route *r = &rl->routes[i];
 	  check_subnet_conflict (r->network, r->netmask, "route");

 	  if (flags & ROUTE_DELETE_FIRST)

 	    delete_route (r, tt, flags, es);
 	  add_route (r, tt, flags, es);

 	}
       rl->routes_added = true;
     }
 }
 
 void
 delete_routes (struct route_list *rl, const struct tuntap *tt, unsigned int flags, const struct env_set *es)
 {
   if (rl->routes_added)
     {
       int i;
       for (i = rl->n - 1; i >= 0; --i)
 	{
 	  const struct route *r = &rl->routes[i];
 	  delete_route (r, tt, flags, es);
 	}
       rl->routes_added = false;
     }
   undo_redirect_default_route_to_vpn (rl, tt, flags, es);
 

   clear_route_list (rl);

 }
 
 #ifdef ENABLE_DEBUG
 
 static const char *
 show_opt (const char *option)
 {
   if (!option)
     return "nil";
   else
     return option;
 }
 
 static void
 print_route_option (const struct route_option *ro, int level)
 {
   msg (level, "  route %s/%s/%s/%s",
        show_opt (ro->network),
        show_opt (ro->netmask),
        show_opt (ro->gateway),
        show_opt (ro->metric));
 }
 
 void
 print_route_options (const struct route_option_list *rol,
 		     int level)
 {
   int i;

   if (rol->flags & RG_ENABLE)

     msg (level, "  [redirect_default_gateway local=%d]",

 	 (rol->flags & RG_LOCAL) != 0);

   for (i = 0; i < rol->n; ++i)
     print_route_option (&rol->routes[i], level);
 }
 
 #endif
 
 static void
 print_route (const struct route *r, int level)
 {
   struct gc_arena gc = gc_new ();
   if (r->defined)
     msg (level, "%s", route_string (r, &gc));
   gc_free (&gc);
 }
 
 void
 print_routes (const struct route_list *rl, int level)
 {
   int i;
   for (i = 0; i < rl->n; ++i)
     print_route (&rl->routes[i], level);
 }
 
 static void
 setenv_route (struct env_set *es, const struct route *r, int i)
 {
   struct gc_arena gc = gc_new ();
   if (r->defined)
     {
       setenv_route_addr (es, "network", r->network, i);
       setenv_route_addr (es, "netmask", r->netmask, i);
       setenv_route_addr (es, "gateway", r->gateway, i);
 
       if (r->metric_defined)
 	{
 	  struct buffer name = alloc_buf_gc (256, &gc);
 	  buf_printf (&name, "route_metric_%d", i);
 	  setenv_int (es, BSTR (&name), r->metric);
 	}
     }
   gc_free (&gc);
 }
 
 void
 setenv_routes (struct env_set *es, const struct route_list *rl)
 {
   int i;
   for (i = 0; i < rl->n; ++i)
     setenv_route (es, &rl->routes[i], i + 1);
 }
 

 void

 add_route (struct route *r, const struct tuntap *tt, unsigned int flags, const struct env_set *es)
 {
   struct gc_arena gc;

   struct argv argv;

   const char *network;
   const char *netmask;
   const char *gateway;
   bool status = false;
 
   if (!r->defined)
     return;
 
   gc_init (&gc);

   argv_init (&argv);

 
   network = print_in_addr_t (r->network, 0, &gc);
   netmask = print_in_addr_t (r->netmask, 0, &gc);
   gateway = print_in_addr_t (r->gateway, 0, &gc);
 
   /*
    * Filter out routes which are essentially no-ops
    */
   if (r->network == r->gateway && r->netmask == 0xFFFFFFFF)
     {
       msg (M_INFO, PACKAGE_NAME " ROUTE: omitted no-op route: %s/%s -> %s",
 	   network, netmask, gateway);
       goto done;
     }
 
 #if defined(TARGET_LINUX)
 #ifdef CONFIG_FEATURE_IPROUTE

   argv_printf (&argv, "%s route add %s/%d via %s",

   	      iproute_path,

 	      network,
 	      count_netmask_bits(netmask),
 	      gateway);
   if (r->metric_defined)

     argv_printf_cat (&argv, "metric %d", r->metric);

 
 #else

   argv_printf (&argv, "%s add -net %s netmask %s gw %s",
 		ROUTE_PATH,

 	      network,
 	      netmask,
 	      gateway);
   if (r->metric_defined)

     argv_printf_cat (&argv, "metric %d", r->metric);

 #endif  /*CONFIG_FEATURE_IPROUTE*/

   argv_msg (D_ROUTE, &argv);
   status = openvpn_execve_check (&argv, es, 0, "ERROR: Linux route add command failed");

 
 #elif defined (WIN32)
 

   argv_printf (&argv, "%s%sc ADD %s MASK %s %s",

 	       get_win_sys_path(),
 	       WIN_ROUTE_PATH_SUFFIX,
 	       network,
 	       netmask,
 	       gateway);

   if (r->metric_defined)

     argv_printf_cat (&argv, "METRIC %d", r->metric);

   argv_msg (D_ROUTE, &argv);

 
   if ((flags & ROUTE_METHOD_MASK) == ROUTE_METHOD_IPAPI)
     {
       status = add_route_ipapi (r, tt);
       msg (D_ROUTE, "Route addition via IPAPI %s", status ? "succeeded" : "failed");
     }
   else if ((flags & ROUTE_METHOD_MASK) == ROUTE_METHOD_EXE)
     {
       netcmd_semaphore_lock ();

       status = openvpn_execve_check (&argv, es, 0, "ERROR: Windows route add command failed");

       netcmd_semaphore_release ();
     }

   else if ((flags & ROUTE_METHOD_MASK) == ROUTE_METHOD_ADAPTIVE)
     {
       status = add_route_ipapi (r, tt);
       msg (D_ROUTE, "Route addition via IPAPI %s [adaptive]", status ? "succeeded" : "failed");
       if (!status)
 	{
 	  msg (D_ROUTE, "Route addition fallback to route.exe");
 	  netcmd_semaphore_lock ();

 	  status = openvpn_execve_check (&argv, es, 0, "ERROR: Windows route add command failed [adaptive]");

 	  netcmd_semaphore_release ();
 	}
     }

   else
     {
       ASSERT (0);
     }
 
 #elif defined (TARGET_SOLARIS)
 
   /* example: route add 192.0.2.32 -netmask 255.255.255.224 somegateway */
 

   argv_printf (&argv, "%s add",
 		ROUTE_PATH);

 
 #if 0
   if (r->metric_defined)

     argv_printf_cat (&argv, "-rtt %d", r->metric);

 #endif
 

   argv_printf_cat (&argv, "%s -netmask %s %s",

 	      network,
 	      netmask,
 	      gateway);
 

   argv_msg (D_ROUTE, &argv);
   status = openvpn_execve_check (&argv, es, 0, "ERROR: Solaris route add command failed");

 
 #elif defined(TARGET_FREEBSD)
 

   argv_printf (&argv, "%s add",
 		ROUTE_PATH);

 
 #if 0
   if (r->metric_defined)

     argv_printf_cat (&argv, "-rtt %d", r->metric);

 #endif
 

   argv_printf_cat (&argv, "-net %s %s %s",

 	      network,
 	      gateway,
 	      netmask);
 

   argv_msg (D_ROUTE, &argv);
   status = openvpn_execve_check (&argv, es, 0, "ERROR: FreeBSD route add command failed");

 #elif defined(TARGET_DRAGONFLY)
 

   argv_printf (&argv, "%s add",
 		ROUTE_PATH);

 
 #if 0
   if (r->metric_defined)

     argv_printf_cat (&argv, "-rtt %d", r->metric);

 #endif
 

   argv_printf_cat (&argv, "-net %s %s %s",

 	      network,
 	      gateway,
 	      netmask);
 

   argv_msg (D_ROUTE, &argv);
   status = openvpn_execve_check (&argv, es, 0, "ERROR: DragonFly route add command failed");

 #elif defined(TARGET_DARWIN)
 

   argv_printf (&argv, "%s add",
 		ROUTE_PATH);

 
 #if 0
   if (r->metric_defined)

     argv_printf_cat (&argv, "-rtt %d", r->metric);

 #endif
 

   argv_printf_cat (&argv, "-net %s %s %s",

               network,
               gateway,
               netmask);
 

   argv_msg (D_ROUTE, &argv);
   status = openvpn_execve_check (&argv, es, 0, "ERROR: OS X route add command failed");

 
 #elif defined(TARGET_OPENBSD) || defined(TARGET_NETBSD)
 

   argv_printf (&argv, "%s add",
 		ROUTE_PATH);

 
 #if 0
   if (r->metric_defined)

     argv_printf_cat (&argv, "-rtt %d", r->metric);

 #endif
 

   argv_printf_cat (&argv, "-net %s %s -netmask %s",

 	      network,
 	      gateway,
 	      netmask);
 

   argv_msg (D_ROUTE, &argv);
   status = openvpn_execve_check (&argv, es, 0, "ERROR: OpenBSD/NetBSD route add command failed");

 
 #else
   msg (M_FATAL, "Sorry, but I don't know how to do 'route' commands on this operating system.  Try putting your routes in a --route-up script");
 #endif
 
  done:
   r->defined = status;

   argv_reset (&argv);

   gc_free (&gc);
 }
 
 static void
 delete_route (const struct route *r, const struct tuntap *tt, unsigned int flags, const struct env_set *es)
 {
   struct gc_arena gc;

   struct argv argv;

   const char *network;
   const char *netmask;
   const char *gateway;
 
   if (!r->defined)
     return;
 
   gc_init (&gc);

   argv_init (&argv);

 
   network = print_in_addr_t (r->network, 0, &gc);
   netmask = print_in_addr_t (r->netmask, 0, &gc);
   gateway = print_in_addr_t (r->gateway, 0, &gc);
 
 #if defined(TARGET_LINUX)
 #ifdef CONFIG_FEATURE_IPROUTE

   argv_printf (&argv, "%s route del %s/%d",

   	      iproute_path,

 	      network,
 	      count_netmask_bits(netmask));
 #else
 

   argv_printf (&argv, "%s del -net %s netmask %s",
 		ROUTE_PATH,

 	      network,
 	      netmask);
 #endif /*CONFIG_FEATURE_IPROUTE*/

   if (r->metric_defined)

     argv_printf_cat (&argv, "metric %d", r->metric);
   argv_msg (D_ROUTE, &argv);
   openvpn_execve_check (&argv, es, 0, "ERROR: Linux route delete command failed");

 
 #elif defined (WIN32)
   

   argv_printf (&argv, "%s%sc DELETE %s MASK %s %s",

 	       get_win_sys_path(),
 	       WIN_ROUTE_PATH_SUFFIX,
 	       network,
 	       netmask,
 	       gateway);

   argv_msg (D_ROUTE, &argv);

 
   if ((flags & ROUTE_METHOD_MASK) == ROUTE_METHOD_IPAPI)
     {
       const bool status = del_route_ipapi (r, tt);
       msg (D_ROUTE, "Route deletion via IPAPI %s", status ? "succeeded" : "failed");
     }
   else if ((flags & ROUTE_METHOD_MASK) == ROUTE_METHOD_EXE)
     {
       netcmd_semaphore_lock ();

       openvpn_execve_check (&argv, es, 0, "ERROR: Windows route delete command failed");

       netcmd_semaphore_release ();
     }

   else if ((flags & ROUTE_METHOD_MASK) == ROUTE_METHOD_ADAPTIVE)
     {
       const bool status = del_route_ipapi (r, tt);
       msg (D_ROUTE, "Route deletion via IPAPI %s [adaptive]", status ? "succeeded" : "failed");
       if (!status)
 	{
 	  msg (D_ROUTE, "Route deletion fallback to route.exe");
 	  netcmd_semaphore_lock ();

 	  openvpn_execve_check (&argv, es, 0, "ERROR: Windows route delete command failed [adaptive]");

 	  netcmd_semaphore_release ();
 	}
     }

   else
     {
       ASSERT (0);
     }
 
 #elif defined (TARGET_SOLARIS)
 

   argv_printf (&argv, "%s delete %s -netmask %s %s",
 		ROUTE_PATH,

 	      network,
 	      netmask,
 	      gateway);
 

   argv_msg (D_ROUTE, &argv);
   openvpn_execve_check (&argv, es, 0, "ERROR: Solaris route delete command failed");

 
 #elif defined(TARGET_FREEBSD)
 

   argv_printf (&argv, "%s delete -net %s %s %s",
 		ROUTE_PATH,

 	      network,
 	      gateway,
 	      netmask);
 

   argv_msg (D_ROUTE, &argv);
   openvpn_execve_check (&argv, es, 0, "ERROR: FreeBSD route delete command failed");

 #elif defined(TARGET_DRAGONFLY)
 

   argv_printf (&argv, "%s delete -net %s %s %s",
 		ROUTE_PATH,

 	      network,
 	      gateway,
 	      netmask);
 

   argv_msg (D_ROUTE, &argv);
   openvpn_execve_check (&argv, es, 0, "ERROR: DragonFly route delete command failed");

 #elif defined(TARGET_DARWIN)
 

   argv_printf (&argv, "%s delete -net %s %s %s",
 		ROUTE_PATH,

               network,
               gateway,
               netmask);
 

   argv_msg (D_ROUTE, &argv);
   openvpn_execve_check (&argv, es, 0, "ERROR: OS X route delete command failed");

 
 #elif defined(TARGET_OPENBSD) || defined(TARGET_NETBSD)
 

   argv_printf (&argv, "%s delete -net %s %s -netmask %s",
 		ROUTE_PATH,

 	      network,
 	      gateway,
 	      netmask);
 

   argv_msg (D_ROUTE, &argv);
   openvpn_execve_check (&argv, es, 0, "ERROR: OpenBSD/NetBSD route delete command failed");

 
 #else
   msg (M_FATAL, "Sorry, but I don't know how to do 'route' commands on this operating system.  Try putting your routes in a --route-up script");
 #endif
 

   argv_reset (&argv);

   gc_free (&gc);
 }
 
 /*
  * The --redirect-gateway option requires OS-specific code below
  * to get the current default gateway.
  */
 
 #if defined(WIN32)
 
 static const MIB_IPFORWARDTABLE *
 get_windows_routing_table (struct gc_arena *gc)
 {
   ULONG size = 0;
   PMIB_IPFORWARDTABLE rt = NULL;
   DWORD status;
 
   status = GetIpForwardTable (NULL, &size, TRUE);
   if (status == ERROR_INSUFFICIENT_BUFFER)
     {
       rt = (PMIB_IPFORWARDTABLE) gc_malloc (size, false, gc);
       status = GetIpForwardTable (rt, &size, TRUE);
       if (status != NO_ERROR)
 	{
 	  msg (D_ROUTE, "NOTE: GetIpForwardTable returned error: %s (code=%u)",
 	       strerror_win32 (status, gc),
 	       (unsigned int)status);
 	  rt = NULL;
 	}
     }
   return rt;
 }
 
 static int
 test_route (const IP_ADAPTER_INFO *adapters,
 	    const in_addr_t gateway,
 	    DWORD *index)
 {
   int count = 0;

   DWORD i = adapter_index_of_ip (adapters, gateway, &count, NULL);

   if (index)
     *index = i;
   return count;
 }
 
 static void
 test_route_helper (bool *ret,
 		   int *count,
 		   int *good,
 		   int *ambig,
 		   const IP_ADAPTER_INFO *adapters,
 		   const in_addr_t gateway)
 {
   int c;
 
   ++*count;
   c = test_route (adapters, gateway, NULL);
   if (c == 0)
     *ret = false;
   else
     ++*good;
   if (c > 1)
     ++*ambig;
 }
 
 /*
  * If we tried to add routes now, would we succeed?
  */
 bool
 test_routes (const struct route_list *rl, const struct tuntap *tt)
 {
   struct gc_arena gc = gc_new ();
   const IP_ADAPTER_INFO *adapters = get_adapter_info_list (&gc);
   bool ret = false;
   int count = 0;
   int good = 0;
   int ambig = 0;
   bool adapter_up = false;
 
   if (is_adapter_up (tt, adapters))
     {
       ret = true;
       adapter_up = true;
 
       if (rl)
 	{
 	  int i;
 	  for (i = 0; i < rl->n; ++i)
 	    test_route_helper (&ret, &count, &good, &ambig, adapters, rl->routes[i].gateway);
 

 	  if ((rl->flags & RG_ENABLE) && rl->spec.remote_endpoint_defined)

 	    test_route_helper (&ret, &count, &good, &ambig, adapters, rl->spec.remote_endpoint);
 	}
     }
 
   msg (D_ROUTE, "TEST ROUTES: %d/%d succeeded len=%d ret=%d a=%d u/d=%s",
        good,
        count,
        rl ? rl->n : -1,
        (int)ret,
        ambig,
        adapter_up ? "up" : "down");
 
   gc_free (&gc);
   return ret;
 }
 

 static const MIB_IPFORWARDROW *
 get_default_gateway_row (const MIB_IPFORWARDTABLE *routes)

 {

   struct gc_arena gc = gc_new ();
   DWORD lowest_metric = ~0;

   const MIB_IPFORWARDROW *ret = NULL;

   int i;

   int best = -1;

   if (routes)

     {

       for (i = 0; i < routes->dwNumEntries; ++i)
 	{
 	  const MIB_IPFORWARDROW *row = &routes->table[i];
 	  const in_addr_t net = ntohl (row->dwForwardDest);
 	  const in_addr_t mask = ntohl (row->dwForwardMask);
 	  const DWORD index = row->dwForwardIfIndex;

 	  const DWORD metric = row->dwForwardMetric1;

 	  dmsg (D_ROUTE_DEBUG, "GDGR: route[%d] %s/%s i=%d m=%d",
 		i,
 		print_in_addr_t ((in_addr_t) net, 0, &gc),
 		print_in_addr_t ((in_addr_t) mask, 0, &gc),
 		(int)index,
 		(int)metric);

 	  if (!net && !mask && metric < lowest_metric)

 	    {
 	      ret = row;

 	      lowest_metric = metric;
 	      best = i;

 	    }

 	}
     }

 
   dmsg (D_ROUTE_DEBUG, "GDGR: best=%d lm=%u", best, (unsigned int)lowest_metric);
 
   gc_free (&gc);

   return ret;
 }
 

 bool
 get_default_gateway (in_addr_t *gw, in_addr_t *netmask)

 {
   struct gc_arena gc = gc_new ();
   bool ret_bool = false;
 

   const IP_ADAPTER_INFO *adapters = get_adapter_info_list (&gc);

   const MIB_IPFORWARDTABLE *routes = get_windows_routing_table (&gc);
   const MIB_IPFORWARDROW *row = get_default_gateway_row (routes);
 
   if (row)
     {

       *gw = ntohl (row->dwForwardNextHop);
       if (netmask)
 	{
 	  if (adapter_index_of_ip (adapters, *gw, NULL, netmask) == ~0)
 	    *netmask = ~0;
 	}

       ret_bool = true;
     }
 

   gc_free (&gc);
   return ret_bool;
 }
 
 static DWORD
 windows_route_find_if_index (const struct route *r, const struct tuntap *tt)
 {
   struct gc_arena gc = gc_new ();
   DWORD ret = ~0;
   int count = 0;
   const IP_ADAPTER_INFO *adapters = get_adapter_info_list (&gc);
   const IP_ADAPTER_INFO *tun_adapter = get_tun_adapter (tt, adapters);
   bool on_tun = false;
 
   /* first test on tun interface */
   if (is_ip_in_adapter_subnet (tun_adapter, r->gateway, NULL))
     {
       ret = tun_adapter->Index;
       count = 1;
       on_tun = true;
     }
   else /* test on other interfaces */
     {
       count = test_route (adapters, r->gateway, &ret);
     }
 
   if (count == 0)
     {
       msg (M_WARN, "Warning: route gateway is not reachable on any active network adapters: %s",
 	   print_in_addr_t (r->gateway, 0, &gc));
       ret = ~0;
     }
   else if (count > 1)
     {
       msg (M_WARN, "Warning: route gateway is ambiguous: %s (%d matches)",
 	   print_in_addr_t (r->gateway, 0, &gc),
 	   count);
       ret = ~0;
     }
 
   dmsg (D_ROUTE_DEBUG, "DEBUG: route find if: on_tun=%d count=%d index=%d",
        on_tun,
        count,
        (int)ret);
 
   gc_free (&gc);
   return ret;
 }
 
 bool
 add_route_ipapi (const struct route *r, const struct tuntap *tt)
 {
   struct gc_arena gc = gc_new ();
   bool ret = false;
   DWORD status;
   const DWORD if_index = windows_route_find_if_index (r, tt);  
 
   if (if_index != ~0)
     {
       MIB_IPFORWARDROW fr;
       CLEAR (fr);
       fr.dwForwardDest = htonl (r->network);
       fr.dwForwardMask = htonl (r->netmask);
       fr.dwForwardPolicy = 0;
       fr.dwForwardNextHop = htonl (r->gateway);
       fr.dwForwardIfIndex = if_index;
       fr.dwForwardType = 4;  /* the next hop is not the final dest */
       fr.dwForwardProto = 3; /* PROTO_IP_NETMGMT */
       fr.dwForwardAge = 0;
       fr.dwForwardNextHopAS = 0;
       fr.dwForwardMetric1 = r->metric_defined ? r->metric : 1;
       fr.dwForwardMetric2 = ~0;
       fr.dwForwardMetric3 = ~0;
       fr.dwForwardMetric4 = ~0;
       fr.dwForwardMetric5 = ~0;
 
       if ((r->network & r->netmask) != r->network)
 	msg (M_WARN, "Warning: address %s is not a network address in relation to netmask %s",
 	     print_in_addr_t (r->network, 0, &gc),
 	     print_in_addr_t (r->netmask, 0, &gc));
 
       status = CreateIpForwardEntry (&fr);
 
       if (status == NO_ERROR)
 	ret = true;
       else
 	{

 	  /* failed, try increasing the metric to work around Vista issue */
 	  const unsigned int forward_metric_limit = 2048; /* iteratively retry higher metrics up to this limit */

 	  for ( ; fr.dwForwardMetric1 <= forward_metric_limit; ++fr.dwForwardMetric1)
 	    {
 	      /* try a different forward type=3 ("the next hop is the final dest") in addition to 4.
 		 --redirect-gateway over RRAS seems to need this. */
 	      for (fr.dwForwardType = 4; fr.dwForwardType >= 3; --fr.dwForwardType)
 		{
 		  status = CreateIpForwardEntry (&fr);
 		  if (status == NO_ERROR)
 		    {
 		      msg (D_ROUTE, "ROUTE: CreateIpForwardEntry succeeded with dwForwardMetric1=%u and dwForwardType=%u",
 			   (unsigned int)fr.dwForwardMetric1,
 			   (unsigned int)fr.dwForwardType);
 		      ret = true;
 		      goto doublebreak;
 		    }
 		  else if (status != ERROR_BAD_ARGUMENTS)
 		    goto doublebreak;
 		}
 	    }

 	doublebreak:
 	  if (status != NO_ERROR)
 	    msg (M_WARN, "ROUTE: route addition failed using CreateIpForwardEntry: %s [status=%u if_index=%u]",

 		 strerror_win32 (status, &gc),

 		 (unsigned int)status,

 		 (unsigned int)if_index);
 	}
     }
 
   gc_free (&gc);
   return ret;
 }
 
 bool
 del_route_ipapi (const struct route *r, const struct tuntap *tt)
 {
   struct gc_arena gc = gc_new ();
   bool ret = false;
   DWORD status;
   const DWORD if_index = windows_route_find_if_index (r, tt);
 
   if (if_index != ~0)
     {
       MIB_IPFORWARDROW fr;
       CLEAR (fr);
 
       fr.dwForwardDest = htonl (r->network);
       fr.dwForwardMask = htonl (r->netmask);
       fr.dwForwardPolicy = 0;
       fr.dwForwardNextHop = htonl (r->gateway);
       fr.dwForwardIfIndex = if_index;
 
       status = DeleteIpForwardEntry (&fr);
 
       if (status == NO_ERROR)
 	ret = true;
       else
 	msg (M_WARN, "ROUTE: route deletion failed using DeleteIpForwardEntry: %s",
 	     strerror_win32 (status, &gc));
     }
 
   gc_free (&gc);
   return ret;
 }
 
 static const char *
 format_route_entry (const MIB_IPFORWARDROW *r, struct gc_arena *gc)
 {
   struct buffer out = alloc_buf_gc (256, gc);
   buf_printf (&out, "%s %s %s p=%d i=%d t=%d pr=%d a=%d h=%d m=%d/%d/%d/%d/%d", 
 	      print_in_addr_t (r->dwForwardDest, IA_NET_ORDER, gc),
 	      print_in_addr_t (r->dwForwardMask, IA_NET_ORDER, gc),
 	      print_in_addr_t (r->dwForwardNextHop, IA_NET_ORDER, gc),
 	      (int)r->dwForwardPolicy,
 	      (int)r->dwForwardIfIndex,
 	      (int)r->dwForwardType,
 	      (int)r->dwForwardProto,
 	      (int)r->dwForwardAge,
 	      (int)r->dwForwardNextHopAS,
 	      (int)r->dwForwardMetric1,
 	      (int)r->dwForwardMetric2,
 	      (int)r->dwForwardMetric3,
 	      (int)r->dwForwardMetric4,
 	      (int)r->dwForwardMetric5);
   return BSTR (&out);
 }
 
 /*
  * Show current routing table
  */
 void
 show_routes (int msglev)
 {
   struct gc_arena gc = gc_new ();
   int i;
 
   const MIB_IPFORWARDTABLE *rt = get_windows_routing_table (&gc);
 
   msg (msglev, "SYSTEM ROUTING TABLE");
   if (rt)
     {
       for (i = 0; i < rt->dwNumEntries; ++i)
 	{
 	  msg (msglev, "%s", format_route_entry (&rt->table[i], &gc));
 	}
     }
   gc_free (&gc);
 }
 
 #elif defined(TARGET_LINUX)
 

 bool
 get_default_gateway (in_addr_t *gateway, in_addr_t *netmask)

 {
   struct gc_arena gc = gc_new ();

   bool ret = false;

   FILE *fp = fopen ("/proc/net/route", "r");
   if (fp)
     {
       char line[256];
       int count = 0;

       int best_count = 0;
       unsigned int lowest_metric = ~0;
       in_addr_t best_gw = 0;

       while (fgets (line, sizeof (line), fp) != NULL)
 	{
 	  if (count)
 	    {
 	      unsigned int net_x = 0;
 	      unsigned int mask_x = 0;
 	      unsigned int gw_x = 0;

 	      unsigned int metric = 0;
 	      const int np = sscanf (line, "%*s\t%x\t%x\t%*s\t%*s\t%*s\t%d\t%x",

 				     &net_x,
 				     &gw_x,

 				     &metric,

 				     &mask_x);

 	      if (np == 4)

 		{
 		  const in_addr_t net = ntohl (net_x);
 		  const in_addr_t mask = ntohl (mask_x);
 		  const in_addr_t gw = ntohl (gw_x);

 
 		  dmsg (D_ROUTE_DEBUG, "GDG: route[%d] %s/%s/%s m=%u",
 			count,
 			print_in_addr_t ((in_addr_t) net, 0, &gc),
 			print_in_addr_t ((in_addr_t) mask, 0, &gc),
 			print_in_addr_t ((in_addr_t) gw, 0, &gc),
 			metric);
 
 		  if (!net && !mask && metric < lowest_metric)

 		    {

 		      best_gw = gw;
 		      lowest_metric = metric;
 		      best_count = count;

 		    }
 		}
 	    }
 	  ++count;
 	}
       fclose (fp);

 
       if (best_gw)

 	{
 	  *gateway = best_gw;

 	  if (netmask)
 	    {

 	      *netmask = 0xFFFFFF00; /* FIXME -- get the real netmask of the adapter containing the default gateway */

 	    }

 	  ret = true;
 	}

 
       dmsg (D_ROUTE_DEBUG, "GDG: best=%s[%d] lm=%u",
 	    print_in_addr_t ((in_addr_t) best_gw, 0, &gc),
 	    best_count,
 	    (unsigned int)lowest_metric);

     }
 
   gc_free (&gc);

   return ret;

 }
 

 #elif defined(TARGET_FREEBSD)||defined(TARGET_DRAGONFLY)

 
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 
 /* all of this is taken from <net/route.h> in FreeBSD */
 #define RTA_DST     0x1
 #define RTA_GATEWAY 0x2
 #define RTA_NETMASK 0x4
 
 #define RTM_GET     0x4
 #define RTM_VERSION 5
 
 #define RTF_UP      0x1
 #define RTF_GATEWAY 0x2
 
 /*
  * These numbers are used by reliable protocols for determining
  * retransmission behavior and are included in the routing structure.
  */
 struct rt_metrics {
         u_long  rmx_locks;      /* Kernel must leave these values alone */
         u_long  rmx_mtu;        /* MTU for this path */
         u_long  rmx_hopcount;   /* max hops expected */
         u_long  rmx_expire;     /* lifetime for route, e.g. redirect */
         u_long  rmx_recvpipe;   /* inbound delay-bandwidth product */
         u_long  rmx_sendpipe;   /* outbound delay-bandwidth product */
         u_long  rmx_ssthresh;   /* outbound gateway buffer limit */
         u_long  rmx_rtt;        /* estimated round trip time */
         u_long  rmx_rttvar;     /* estimated rtt variance */
         u_long  rmx_pksent;     /* packets sent using this route */
         u_long  rmx_filler[4];  /* will be used for T/TCP later */
 };
 
 /*
  * Structures for routing messages.
  */
 struct rt_msghdr {
         u_short rtm_msglen;     /* to skip over non-understood messages */
         u_char  rtm_version;    /* future binary compatibility */
         u_char  rtm_type;       /* message type */
         u_short rtm_index;      /* index for associated ifp */
         int     rtm_flags;      /* flags, incl. kern & message, e.g. DONE */
         int     rtm_addrs;      /* bitmask identifying sockaddrs in msg */
         pid_t   rtm_pid;        /* identify sender */
         int     rtm_seq;        /* for sender to identify action */
         int     rtm_errno;      /* why failed */
         int     rtm_use;        /* from rtentry */
         u_long  rtm_inits;      /* which metrics we are initializing */
         struct  rt_metrics rtm_rmx; /* metrics themselves */
 };
 
 struct {
   struct rt_msghdr m_rtm;
   char       m_space[512];
 } m_rtmsg;
 
 #define ROUNDUP(a) \
         ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
 

 bool
 get_default_gateway (in_addr_t *ret, in_addr_t *netmask)

 {
   struct gc_arena gc = gc_new ();
   int s, seq, l, pid, rtm_addrs, i;
   struct sockaddr so_dst, so_mask;
   char *cp = m_rtmsg.m_space; 
   struct sockaddr *gate = NULL, *sa;
   struct  rt_msghdr *rtm_aux;
 
 #define NEXTADDR(w, u) \
         if (rtm_addrs & (w)) {\
             l = ROUNDUP(u.sa_len); memmove(cp, &(u), l); cp += l;\
         }
 
 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))
 
 #define rtm m_rtmsg.m_rtm
 
   pid = getpid();
   seq = 0;
   rtm_addrs = RTA_DST | RTA_NETMASK;
 
   bzero(&so_dst, sizeof(so_dst));
   bzero(&so_mask, sizeof(so_mask));
   bzero(&rtm, sizeof(struct rt_msghdr));
 
   rtm.rtm_type = RTM_GET;
   rtm.rtm_flags = RTF_UP | RTF_GATEWAY;
   rtm.rtm_version = RTM_VERSION;
   rtm.rtm_seq = ++seq;
   rtm.rtm_addrs = rtm_addrs; 
 
   so_dst.sa_family = AF_INET;
   so_dst.sa_len = sizeof(struct sockaddr_in);
   so_mask.sa_family = AF_INET;
   so_mask.sa_len = sizeof(struct sockaddr_in);
 
   NEXTADDR(RTA_DST, so_dst);
   NEXTADDR(RTA_NETMASK, so_mask);
 
   rtm.rtm_msglen = l = cp - (char *)&m_rtmsg;
 
   s = socket(PF_ROUTE, SOCK_RAW, 0);
 
   if (write(s, (char *)&m_rtmsg, l) < 0)
     {
       warn("writing to routing socket");
       gc_free (&gc);
       close(s);
       return false;
     }
 
   do {
     l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
   } while (l > 0 && (rtm.rtm_seq != seq || rtm.rtm_pid != pid));
                         
   close(s);
 
   rtm_aux = &rtm;
 
   cp = ((char *)(rtm_aux + 1));
   if (rtm_aux->rtm_addrs) {
     for (i = 1; i; i <<= 1)
       if (i & rtm_aux->rtm_addrs) {
 	sa = (struct sockaddr *)cp;
 	if (i == RTA_GATEWAY )
 	  gate = sa;
 	ADVANCE(cp, sa);
       }
   }
   else
     {
       gc_free (&gc);
       return false;
     }
 
 
   if (gate != NULL )
     {
       *ret = ntohl(((struct sockaddr_in *)gate)->sin_addr.s_addr);

 #if 0

       msg (M_INFO, "gw %s",
 	   print_in_addr_t ((in_addr_t) *ret, 0, &gc));
 #endif
 

       if (netmask)
 	{
 	  *netmask = 0xFFFFFF00; // FIXME -- get the real netmask of the adapter containing the default gateway
 	}
 

       gc_free (&gc);
       return true;
     }
   else
     {
       gc_free (&gc);
       return false;
     }
 }
 
 #elif defined(TARGET_DARWIN)
 
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 
 /* all of this is taken from <net/route.h> in Darwin */
 #define RTA_DST     0x1
 #define RTA_GATEWAY 0x2
 #define RTA_NETMASK 0x4
 
 #define RTM_GET     0x4
 #define RTM_VERSION 5
 
 #define RTF_UP      0x1
 #define RTF_GATEWAY 0x2
 
 /*
  * These numbers are used by reliable protocols for determining
  * retransmission behavior and are included in the routing structure.
  */
 struct rt_metrics {
         u_long  rmx_locks;      /* Kernel must leave these values alone */
         u_long  rmx_mtu;        /* MTU for this path */
         u_long  rmx_hopcount;   /* max hops expected */
         u_long  rmx_expire;     /* lifetime for route, e.g. redirect */
         u_long  rmx_recvpipe;   /* inbound delay-bandwidth product */
         u_long  rmx_sendpipe;   /* outbound delay-bandwidth product */
         u_long  rmx_ssthresh;   /* outbound gateway buffer limit */
         u_long  rmx_rtt;        /* estimated round trip time */
         u_long  rmx_rttvar;     /* estimated rtt variance */
         u_long  rmx_pksent;     /* packets sent using this route */
         u_long  rmx_filler[4];  /* will be used for T/TCP later */
 };
 
 /*
  * Structures for routing messages.
  */
 struct rt_msghdr {
         u_short rtm_msglen;     /* to skip over non-understood messages */
         u_char  rtm_version;    /* future binary compatibility */
         u_char  rtm_type;       /* message type */
         u_short rtm_index;      /* index for associated ifp */
         int     rtm_flags;      /* flags, incl. kern & message, e.g. DONE */
         int     rtm_addrs;      /* bitmask identifying sockaddrs in msg */
         pid_t   rtm_pid;        /* identify sender */
         int     rtm_seq;        /* for sender to identify action */
         int     rtm_errno;      /* why failed */
         int     rtm_use;        /* from rtentry */
         u_long  rtm_inits;      /* which metrics we are initializing */
         struct  rt_metrics rtm_rmx; /* metrics themselves */
 };
 
 struct {
   struct rt_msghdr m_rtm;
   char       m_space[512];
 } m_rtmsg;
 
 #define ROUNDUP(a) \
         ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
 

 bool
 get_default_gateway (in_addr_t *ret, in_addr_t *netmask)

 {
   struct gc_arena gc = gc_new ();
   int s, seq, l, pid, rtm_addrs, i;
   struct sockaddr so_dst, so_mask;
   char *cp = m_rtmsg.m_space; 
   struct sockaddr *gate = NULL, *sa;
   struct  rt_msghdr *rtm_aux;
 
 #define NEXTADDR(w, u) \
         if (rtm_addrs & (w)) {\
             l = ROUNDUP(u.sa_len); memmove(cp, &(u), l); cp += l;\
         }
 
 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))
 
 #define rtm m_rtmsg.m_rtm
 
   pid = getpid();
   seq = 0;
   rtm_addrs = RTA_DST | RTA_NETMASK;
 
   bzero(&so_dst, sizeof(so_dst));
   bzero(&so_mask, sizeof(so_mask));
   bzero(&rtm, sizeof(struct rt_msghdr));
 
   rtm.rtm_type = RTM_GET;
   rtm.rtm_flags = RTF_UP | RTF_GATEWAY;
   rtm.rtm_version = RTM_VERSION;
   rtm.rtm_seq = ++seq;
   rtm.rtm_addrs = rtm_addrs; 
 
   so_dst.sa_family = AF_INET;
   so_dst.sa_len = sizeof(struct sockaddr_in);
   so_mask.sa_family = AF_INET;
   so_mask.sa_len = sizeof(struct sockaddr_in);
 
   NEXTADDR(RTA_DST, so_dst);
   NEXTADDR(RTA_NETMASK, so_mask);
 
   rtm.rtm_msglen = l = cp - (char *)&m_rtmsg;
 
   s = socket(PF_ROUTE, SOCK_RAW, 0);
 
   if (write(s, (char *)&m_rtmsg, l) < 0)
     {
       msg (M_WARN, "ROUTE: problem writing to routing socket");
       gc_free (&gc);
       close(s);
       return false;
     }
 
   do {
     l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
   } while (l > 0 && (rtm.rtm_seq != seq || rtm.rtm_pid != pid));
                         
   close(s);
 
   rtm_aux = &rtm;
 
   cp = ((char *)(rtm_aux + 1));
   if (rtm_aux->rtm_addrs) {
     for (i = 1; i; i <<= 1)
       if (i & rtm_aux->rtm_addrs) {
 	sa = (struct sockaddr *)cp;
 	if (i == RTA_GATEWAY )
 	  gate = sa;
 	ADVANCE(cp, sa);
       }
   }
   else
     {
       gc_free (&gc);
       return false;
     }
 
 
   if (gate != NULL )
     {
       *ret = ntohl(((struct sockaddr_in *)gate)->sin_addr.s_addr);

 #if 0

       msg (M_INFO, "gw %s",
 	   print_in_addr_t ((in_addr_t) *ret, 0, &gc));
 #endif
 

       if (netmask)
 	{
 	  *netmask = 0xFFFFFF00; // FIXME -- get the real netmask of the adapter containing the default gateway
 	}
 

       gc_free (&gc);
       return true;
     }
   else
     {
       gc_free (&gc);
       return false;
     }
 }
 
 #elif defined(TARGET_OPENBSD) || defined(TARGET_NETBSD)
 
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 
 /* all of this is taken from <net/route.h> in OpenBSD 3.6 */
 #define RTA_DST		0x1	/* destination sockaddr present */
 #define RTA_GATEWAY	0x2	/* gateway sockaddr present */
 #define RTA_NETMASK	0x4	/* netmask sockaddr present */
 
 #define RTM_GET		0x4	/* Report Metrics */
 
 #define RTM_VERSION	3	/* Up the ante and ignore older versions */
 
 #define	RTF_UP		0x1		/* route usable */
 #define	RTF_GATEWAY	0x2		/* destination is a gateway */
 
 /*
  * Huge version for userland compatibility.
  */
 struct rt_metrics {
 	u_long	rmx_locks;	/* Kernel must leave these values alone */
 	u_long	rmx_mtu;	/* MTU for this path */
 	u_long	rmx_hopcount;	/* max hops expected */
 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
 	u_long	rmx_recvpipe;	/* inbound delay-bandwidth product */
 	u_long	rmx_sendpipe;	/* outbound delay-bandwidth product */
 	u_long	rmx_ssthresh;	/* outbound gateway buffer limit */
 	u_long	rmx_rtt;	/* estimated round trip time */
 	u_long	rmx_rttvar;	/* estimated rtt variance */
 	u_long	rmx_pksent;	/* packets sent using this route */
 };
 
 /*
  * Structures for routing messages.
  */
 struct rt_msghdr {
 	u_short	rtm_msglen;	/* to skip over non-understood messages */
 	u_char	rtm_version;	/* future binary compatibility */
 	u_char	rtm_type;	/* message type */
 	u_short	rtm_index;	/* index for associated ifp */
 	int	rtm_flags;	/* flags, incl. kern & message, e.g. DONE */
 	int	rtm_addrs;	/* bitmask identifying sockaddrs in msg */
 	pid_t	rtm_pid;	/* identify sender */
 	int	rtm_seq;	/* for sender to identify action */
 	int	rtm_errno;	/* why failed */
 	int	rtm_use;	/* from rtentry */
 	u_long	rtm_inits;	/* which metrics we are initializing */
 	struct	rt_metrics rtm_rmx; /* metrics themselves */
 };
 
 struct {
   struct rt_msghdr m_rtm;
   char       m_space[512];
 } m_rtmsg;
 
 #define ROUNDUP(a) \
         ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
 

 bool
 get_default_gateway (in_addr_t *ret, in_addr_t *netmask)

 {
   struct gc_arena gc = gc_new ();
   int s, seq, l, rtm_addrs, i;
   pid_t pid;
   struct sockaddr so_dst, so_mask;
   char *cp = m_rtmsg.m_space; 
   struct sockaddr *gate = NULL, *sa;
   struct  rt_msghdr *rtm_aux;
 
 #define NEXTADDR(w, u) \
         if (rtm_addrs & (w)) {\
             l = ROUNDUP(u.sa_len); memmove(cp, &(u), l); cp += l;\
         }
 
 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))
 
 #define rtm m_rtmsg.m_rtm
 
   pid = getpid();
   seq = 0;
   rtm_addrs = RTA_DST | RTA_NETMASK;
 
   bzero(&so_dst, sizeof(so_dst));
   bzero(&so_mask, sizeof(so_mask));
   bzero(&rtm, sizeof(struct rt_msghdr));
 
   rtm.rtm_type = RTM_GET;
   rtm.rtm_flags = RTF_UP | RTF_GATEWAY;
   rtm.rtm_version = RTM_VERSION;
   rtm.rtm_seq = ++seq;
   rtm.rtm_addrs = rtm_addrs; 
 
   so_dst.sa_family = AF_INET;
   so_dst.sa_len = sizeof(struct sockaddr_in);
   so_mask.sa_family = AF_INET;
   so_mask.sa_len = sizeof(struct sockaddr_in);
 
   NEXTADDR(RTA_DST, so_dst);
   NEXTADDR(RTA_NETMASK, so_mask);
 
   rtm.rtm_msglen = l = cp - (char *)&m_rtmsg;
 
   s = socket(PF_ROUTE, SOCK_RAW, 0);
 
   if (write(s, (char *)&m_rtmsg, l) < 0)
     {
       warn("writing to routing socket");
       gc_free (&gc);
       close(s);
       return false;
     }
 
   do {
     l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
   } while (l > 0 && (rtm.rtm_seq != seq || rtm.rtm_pid != pid));
                         
   close(s);
 
   rtm_aux = &rtm;
 
   cp = ((char *)(rtm_aux + 1));
   if (rtm_aux->rtm_addrs) {
     for (i = 1; i; i <<= 1)
       if (i & rtm_aux->rtm_addrs) {
 	sa = (struct sockaddr *)cp;
 	if (i == RTA_GATEWAY )
 	  gate = sa;
 	ADVANCE(cp, sa);
       }
   }
   else
     {
       gc_free (&gc);
       return false;
     }
 
 
   if (gate != NULL )
     {
       *ret = ntohl(((struct sockaddr_in *)gate)->sin_addr.s_addr);

 #if 0

       msg (M_INFO, "gw %s",
 	   print_in_addr_t ((in_addr_t) *ret, 0, &gc));
 #endif
 

       if (netmask)
 	{
 	  *netmask = 0xFFFFFF00; // FIXME -- get the real netmask of the adapter containing the default gateway
 	}
 

       gc_free (&gc);
       return true;
     }
   else
     {
       gc_free (&gc);
       return false;
     }
 }
 
 #else
 

 bool

 get_default_gateway (in_addr_t *ret, in_addr_t *netmask)  /* PLATFORM-SPECIFIC */

 {
   return false;
 }
 
 #endif
 
 bool
 netmask_to_netbits (const in_addr_t network, const in_addr_t netmask, int *netbits)
 {
   int i;
   const int addrlen = sizeof (in_addr_t) * 8;
 
   if ((network & netmask) == network)
     {
       for (i = 0; i <= addrlen; ++i)
 	{
 	  in_addr_t mask = netbits_to_netmask (i);
 	  if (mask == netmask)
 	    {
 	      if (i == addrlen)
 		*netbits = -1;
 	      else
 		*netbits = i;
 	      return true;
 	    }
 	}
     }
   return false;
 }

 
 /*
  * get_bypass_addresses() is used by the redirect-gateway bypass-x
  * functions to build a route bypass to selected DHCP/DNS servers,
  * so that outgoing packets to these servers don't end up in the tunnel.
  */
 
 #if defined(WIN32)
 
 static void

 add_host_route_if_nonlocal (struct route_bypass *rb, const in_addr_t addr)

 {

   if (test_local_addr(addr) == TLA_NONLOCAL && addr != 0 && addr != ~0)

     add_bypass_address (rb, addr);
 }
 
 static void

 add_host_route_array (struct route_bypass *rb, const IP_ADDR_STRING *iplist)

 {
   while (iplist)
     {
       bool succeed = false;
       const in_addr_t ip = getaddr (GETADDR_HOST_ORDER, iplist->IpAddress.String, 0, &succeed, NULL);
       if (succeed)
 	{

 	  add_host_route_if_nonlocal (rb, ip);

 	}
       iplist = iplist->Next;
     }
 }
 
 static void
 get_bypass_addresses (struct route_bypass *rb, const unsigned int flags)
 {
   struct gc_arena gc = gc_new ();

   /*bool ret_bool = false;*/

 
   /* get full routing table */
   const MIB_IPFORWARDTABLE *routes = get_windows_routing_table (&gc);
 
   /* get the route which represents the default gateway */
   const MIB_IPFORWARDROW *row = get_default_gateway_row (routes);
 
   if (row)
     {
       /* get the adapter which the default gateway is associated with */
       const IP_ADAPTER_INFO *dgi = get_adapter_info (row->dwForwardIfIndex, &gc);
 
       /* get extra adapter info, such as DNS addresses */
       const IP_PER_ADAPTER_INFO *pai = get_per_adapter_info (row->dwForwardIfIndex, &gc);
 
       /* Bypass DHCP server address */
       if ((flags & RG_BYPASS_DHCP) && dgi && dgi->DhcpEnabled)

 	add_host_route_array (rb, &dgi->DhcpServer);

 
       /* Bypass DNS server addresses */
       if ((flags & RG_BYPASS_DNS) && pai)

 	add_host_route_array (rb, &pai->DnsServerList);

     }
 
   gc_free (&gc);
 }
 
 #else
 
 static void

 get_bypass_addresses (struct route_bypass *rb, const unsigned int flags)  /* PLATFORM-SPECIFIC */

 {
 }
 
 #endif

 #if AUTO_USERID || defined(ENABLE_PUSH_PEER_INFO)

 
 #if defined(TARGET_LINUX)
 
 bool
 get_default_gateway_mac_addr (unsigned char *macaddr)
 {
   struct ifreq *ifr, *ifend;
   in_addr_t ina, mask;
   struct ifreq ifreq;
   struct ifconf ifc;
   struct ifreq ifs[20]; // Maximum number of interfaces to scan
   int sd = -1;
   in_addr_t gwip = 0;
   bool ret = false;
 

   if (!get_default_gateway (&gwip, NULL))

     {
       msg (M_WARN, "GDGMA: get_default_gateway failed");
       goto err;
     }
 
   if ((sd = socket (AF_INET, SOCK_DGRAM, 0)) < 0)
     {
       msg (M_WARN, "GDGMA: socket() failed");
       goto err;
     }
 
   ifc.ifc_len = sizeof (ifs);
   ifc.ifc_req = ifs;
   if (ioctl (sd, SIOCGIFCONF, &ifc) < 0)
     {
       msg (M_WARN, "GDGMA: ioctl(SIOCGIFCONF) failed");
       goto err;
     }
 
   /* scan through interface list */
   ifend = ifs + (ifc.ifc_len / sizeof (struct ifreq));
   for (ifr = ifc.ifc_req; ifr < ifend; ifr++)
     {
       if (ifr->ifr_addr.sa_family == AF_INET)
 	{
 	  ina = ntohl(((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr);
 	  strncpynt (ifreq.ifr_name, ifr->ifr_name, sizeof (ifreq.ifr_name));
 
 	  dmsg (D_AUTO_USERID, "GDGMA: %s", ifreq.ifr_name);
 
 	  /* check that the interface is up, and not point-to-point or loopback */
 	  if (ioctl (sd, SIOCGIFFLAGS, &ifreq) < 0)
 	    {
 	      dmsg (D_AUTO_USERID, "GDGMA: SIOCGIFFLAGS(%s) failed", ifreq.ifr_name);
 	      continue;
 	    }
 
 	  if ((ifreq.ifr_flags & (IFF_UP|IFF_LOOPBACK)) != IFF_UP)
 	    {
 	      dmsg (D_AUTO_USERID, "GDGMA: interface %s is down or loopback", ifreq.ifr_name);
 	      continue;
 	    }
 
 	  /* get interface netmask and check for correct subnet */
 	  if (ioctl (sd, SIOCGIFNETMASK, &ifreq) < 0)
 	    {
 	      dmsg (D_AUTO_USERID, "GDGMA: SIOCGIFNETMASK(%s) failed", ifreq.ifr_name);
 	      continue;
 	    }
 
 	  mask = ntohl(((struct sockaddr_in *) &ifreq.ifr_addr)->sin_addr.s_addr);
 	  if (((gwip ^ ina) & mask) != 0)
 	    {
 	      dmsg (D_AUTO_USERID, "GDGMA: gwip=0x%08x ina=0x%08x mask=0x%08x",
 		    (unsigned int)gwip,
 		    (unsigned int)ina,
 		    (unsigned int)mask);
 	      continue;
 	    }
 	  break;
 	}
     }
   if (ifr >= ifend)
     {
       msg (M_WARN, "GDGMA: couldn't find gw interface");
       goto err;
     }
 
   /* now get the hardware address. */
   memset (&ifreq.ifr_hwaddr, 0, sizeof (struct sockaddr));
   if (ioctl (sd, SIOCGIFHWADDR, &ifreq) < 0)
     {
       msg (M_WARN, "GDGMA: SIOCGIFHWADDR(%s) failed", ifreq.ifr_name);
       goto err;
     }
 
   memcpy (macaddr, &ifreq.ifr_hwaddr.sa_data, 6);
   ret = true;
 
  err:
   if (sd >= 0)
     close (sd);
   return ret;
 }
 
 #elif defined(WIN32)
 
 bool
 get_default_gateway_mac_addr (unsigned char *macaddr)
 {
   struct gc_arena gc = gc_new ();
   const IP_ADAPTER_INFO *adapters = get_adapter_info_list (&gc);
   in_addr_t gwip = 0;
   DWORD a_index;
   const IP_ADAPTER_INFO *ai;
 

   if (!get_default_gateway (&gwip, NULL))

     {
       msg (M_WARN, "GDGMA: get_default_gateway failed");
       goto err;
     }
 

   a_index = adapter_index_of_ip (adapters, gwip, NULL, NULL);

   ai = get_adapter (adapters, a_index);
 
   if (!ai)
     {
       msg (M_WARN, "GDGMA: couldn't find gw interface");
       goto err;
     }
 
   memcpy (macaddr, ai->Address, 6);
 
   gc_free (&gc);
   return true;
 
  err:
   gc_free (&gc);
   return false;
 }
 
 #else
 
 bool

 get_default_gateway_mac_addr (unsigned char *macaddr) /* PLATFORM-SPECIFIC */

 {
   return false;
 }
 
 #endif
 #endif /* AUTO_USERID */

 
 /*
  * Test if addr is reachable via a local interface (return ILA_LOCAL),
  * or if it needs to be routed via the default gateway (return
  * ILA_NONLOCAL).  If the target platform doesn't implement this
  * function, return ILA_NOT_IMPLEMENTED.
  *
  * Used by redirect-gateway autolocal feature
  */
 
 #if defined(WIN32)
 
 int
 test_local_addr (const in_addr_t addr)
 {
   struct gc_arena gc = gc_new ();
   const in_addr_t nonlocal_netmask = 0x80000000L; /* routes with netmask <= to this are considered non-local */
   bool ret = TLA_NONLOCAL;
 
   /* get full routing table */
   const MIB_IPFORWARDTABLE *rt = get_windows_routing_table (&gc);
   if (rt)
     {
       int i;
       for (i = 0; i < rt->dwNumEntries; ++i)
 	{
 	  const MIB_IPFORWARDROW *row = &rt->table[i];
 	  const in_addr_t net = ntohl (row->dwForwardDest);
 	  const in_addr_t mask = ntohl (row->dwForwardMask);
 	  if (mask > nonlocal_netmask && (addr & mask) == net)
 	    {
 	      ret = TLA_LOCAL;
 	      break;
 	    }
 	}
     }
 
   gc_free (&gc);
   return ret;
 }
 
 #else
 
 
 int

 test_local_addr (const in_addr_t addr) /* PLATFORM-SPECIFIC */

 {
   return TLA_NOT_IMPLEMENTED;
 }
 
 #endif