/*
  *  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) 2002-2018 OpenVPN 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; if not, write to the Free Software Foundation, Inc.,
  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

  */
 
 /*
  * Support routines for adding/deleting network routes.
  */
 

 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #elif defined(_MSC_VER)
 #include "config-msvc.h"
 #endif
 

 #include "syshead.h"
 
 #include "common.h"
 #include "error.h"
 #include "route.h"

 #include "run_command.h"

 #include "socket.h"
 #include "manage.h"

 #include "win32.h"

 #include "options.h"

 
 #include "memdbg.h"
 

 #if defined(TARGET_LINUX) || defined(TARGET_ANDROID)

 #include <linux/rtnetlink.h>            /* RTM_GETROUTE etc. */

 #endif
 

 #ifdef _WIN32

 #include "openvpn-msg.h"
 

 #define METRIC_NOT_USED ((DWORD)-1)

 static bool add_route_service(const struct route_ipv4 *, const struct tuntap *);
 
 static bool del_route_service(const struct route_ipv4 *, const struct tuntap *);
 
 static bool add_route_ipv6_service(const struct route_ipv6 *, const struct tuntap *);
 
 static bool del_route_ipv6_service(const struct route_ipv6 *, const struct tuntap *);
 

 #endif
 

 static void delete_route(struct route_ipv4 *r, const struct tuntap *tt, unsigned int flags, const struct route_gateway_info *rgi, 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(struct gc_arena *a)

 {

     struct route_option_list *ret;
     ALLOC_OBJ_CLEAR_GC(ret, struct route_option_list, a);
     ret->gc = a;
     return ret;

 }
 

 struct route_ipv6_option_list *

 new_route_ipv6_option_list(struct gc_arena *a)

 {

     struct route_ipv6_option_list *ret;
     ALLOC_OBJ_CLEAR_GC(ret, struct route_ipv6_option_list, a);
     ret->gc = a;
     return ret;

 }
 

 /*
  * NOTE: structs are cloned/copied shallow by design.
  * The routes list from src will stay intact since it is allocated using
  * the options->gc. The cloned/copied lists will share this common tail
  * to avoid copying the data around between pulls. Pulled routes use
  * the c2->gc so they get freed immediately after a reconnect.
  */

 struct route_option_list *

 clone_route_option_list(const struct route_option_list *src, struct gc_arena *a)

 {

     struct route_option_list *ret;
     ALLOC_OBJ_GC(ret, struct route_option_list, a);
     *ret = *src;
     return ret;

 }
 

 struct route_ipv6_option_list *

 clone_route_ipv6_option_list(const struct route_ipv6_option_list *src, struct gc_arena *a)

 {

     struct route_ipv6_option_list *ret;
     ALLOC_OBJ_GC(ret, struct route_ipv6_option_list, a);
     *ret = *src;
     return ret;

 }
 

 void

 copy_route_option_list(struct route_option_list *dest, const struct route_option_list *src, struct gc_arena *a)

 {

     *dest = *src;
     dest->gc = a;

 }
 

 void

 copy_route_ipv6_option_list(struct route_ipv6_option_list *dest,
                             const struct route_ipv6_option_list *src,
                             struct gc_arena *a)

 {

     *dest = *src;
     dest->gc = a;

 }
 

 static const char *

 route_string(const struct route_ipv4 *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->flags & RT_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_list *rl,
                  const char *string,
                  in_addr_t *out,
                  bool *status)
 {
     if (status)
     {
         *status = true;
     }
     if (!strcmp(string, "vpn_gateway"))
     {
         if (rl)
         {
             if (rl->spec.flags & RTSA_REMOTE_ENDPOINT)
             {
                 *out = rl->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 (rl)
         {
             if (rl->rgi.flags & RGI_ADDR_DEFINED)
             {
                 *out = rl->rgi.gateway.addr;
             }
             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 (rl)
         {
             if (rl->spec.flags & RTSA_REMOTE_HOST)
             {
                 *out = rl->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_ipv4 *r,
            struct addrinfo **network_list,
            const struct route_option *ro,
            const struct route_list *rl)

 {

     const in_addr_t default_netmask = IPV4_NETMASK_HOST;
     bool status;
     int ret;
     struct in_addr special;

     CLEAR(*r);
     r->option = ro;

     /* network */

     if (!is_route_parm_defined(ro->network))

     {

         goto fail;

     }

     /* get_special_addr replaces specialaddr with a special ip addr
      * like gw. getaddrinfo is called to convert a a addrinfo struct */

     if (get_special_addr(rl, ro->network, (in_addr_t *) &special.s_addr, &status))

     {

         special.s_addr = htonl(special.s_addr);
         ret = openvpn_getaddrinfo(0, inet_ntoa(special), NULL, 0, NULL,
                                   AF_INET, network_list);
     }
     else
     {
         ret = openvpn_getaddrinfo(GETADDR_RESOLVE | GETADDR_WARN_ON_SIGNAL,
                                   ro->network, NULL, 0, NULL, AF_INET, network_list);

     }

     status = (ret == 0);

     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(rl, 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 (rl->spec.flags & RTSA_REMOTE_ENDPOINT)
         {
             r->gateway = rl->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 = 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->flags |= RT_METRIC_DEFINED;

     }

     else if (rl->spec.flags & RTSA_DEFAULT_METRIC)

     {

         r->metric = rl->spec.default_metric;
         r->flags |= RT_METRIC_DEFINED;

     }
 

     r->flags |= RT_DEFINED;

     return true;

 fail:
     msg(M_WARN, PACKAGE_NAME " ROUTE: failed to parse/resolve route for host/network: %s",
         ro->network);
     return false;

 }
 

 static bool

 init_route_ipv6(struct route_ipv6 *r6,
                 const struct route_ipv6_option *r6o,
                 const struct route_ipv6_list *rl6 )

 {

     CLEAR(*r6);

     if (!get_ipv6_addr( r6o->prefix, &r6->network, &r6->netbits, M_WARN ))
     {
         goto fail;
     }

     /* gateway */
     if (is_route_parm_defined(r6o->gateway))

     {

         if (inet_pton( AF_INET6, r6o->gateway, &r6->gateway ) != 1)

         {

             msg( M_WARN, PACKAGE_NAME "ROUTE6: cannot parse gateway spec '%s'", r6o->gateway );

         }
     }

     else if (rl6->spec_flags & RTSA_REMOTE_ENDPOINT)

     {

         r6->gateway = rl6->remote_endpoint_ipv6;

     }

     else

     {

         msg(M_WARN, PACKAGE_NAME " ROUTE6: " PACKAGE_NAME " needs a gateway parameter for a --route-ipv6 option and no default was specified by either --route-ipv6-gateway or --ifconfig-ipv6 options");
         goto fail;

     }
 

     /* metric */

     r6->metric = -1;
     if (is_route_parm_defined(r6o->metric))

     {

         r6->metric = atoi(r6o->metric);
         if (r6->metric < 0)
         {
             msg(M_WARN, PACKAGE_NAME " ROUTE: route metric for network %s (%s) must be >= 0",
                 r6o->prefix,
                 r6o->metric);
             goto fail;
         }
         r6->flags |= RT_METRIC_DEFINED;

     }

     else if (rl6->spec_flags & RTSA_DEFAULT_METRIC)

     {

         r6->metric = rl6->default_metric;
         r6->flags |= RT_METRIC_DEFINED;

     }
 

     r6->flags |= RT_DEFINED;

     return true;

 fail:
     msg(M_WARN, PACKAGE_NAME " ROUTE: failed to parse/resolve route for host/network: %s",
         r6o->prefix);
     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;
     ALLOC_OBJ_GC(ro, struct route_option, l->gc);
     ro->network = network;
     ro->netmask = netmask;
     ro->gateway = gateway;
     ro->metric = metric;
     ro->next = l->routes;
     l->routes = ro;

 }
 
 void

 add_route_ipv6_to_option_list(struct route_ipv6_option_list *l,
                               const char *prefix,
                               const char *gateway,
                               const char *metric)

 {

     struct route_ipv6_option *ro;
     ALLOC_OBJ_GC(ro, struct route_ipv6_option, l->gc);
     ro->prefix = prefix;
     ro->gateway = gateway;
     ro->metric = metric;
     ro->next = l->routes_ipv6;
     l->routes_ipv6 = ro;

 }
 

 static void

 clear_route_list(struct route_list *rl)

 {

     gc_free(&rl->gc);
     CLEAR(*rl);

 }
 

 static void

 clear_route_ipv6_list(struct route_ipv6_list *rl6)

 {

     gc_free(&rl6->gc);
     CLEAR(*rl6);

 }
 
 void

 route_list_add_vpn_gateway(struct route_list *rl,
                            struct env_set *es,
                            const in_addr_t addr)

 {

     ASSERT(rl);
     rl->spec.remote_endpoint = addr;
     rl->spec.flags |= RTSA_REMOTE_ENDPOINT;
     setenv_route_addr(es, "vpn_gateway", rl->spec.remote_endpoint, -1);

 }
 

 static void

 add_block_local_item(struct route_list *rl,
                      const struct route_gateway_address *gateway,
                      in_addr_t target)

 {

     const int rgi_needed = (RGI_ADDR_DEFINED|RGI_NETMASK_DEFINED);
     if ((rl->rgi.flags & rgi_needed) == rgi_needed
         && rl->rgi.gateway.netmask < 0xFFFFFFFF)

     {

         struct route_ipv4 *r1, *r2;
         unsigned int l2;
 
         ALLOC_OBJ_GC(r1, struct route_ipv4, &rl->gc);
         ALLOC_OBJ_GC(r2, struct route_ipv4, &rl->gc);
 
         /* split a route into two smaller blocking routes, and direct them to target */
         l2 = ((~gateway->netmask)+1)>>1;
         r1->flags = RT_DEFINED;
         r1->gateway = target;
         r1->network = gateway->addr & gateway->netmask;
         r1->netmask = ~(l2-1);
         r1->next = rl->routes;
         rl->routes = r1;
 
         *r2 = *r1;
         r2->network += l2;
         r2->next = rl->routes;
         rl->routes = r2;

     }
 }
 
 static void

 add_block_local(struct route_list *rl)

 {

     const int rgi_needed = (RGI_ADDR_DEFINED|RGI_NETMASK_DEFINED);
     if ((rl->flags & RG_BLOCK_LOCAL)
         && (rl->rgi.flags & rgi_needed) == rgi_needed
         && (rl->spec.flags & RTSA_REMOTE_ENDPOINT)
         && rl->spec.remote_host_local != TLA_LOCAL)

     {

         size_t i;

 #ifndef TARGET_ANDROID

         /* add bypass for gateway addr */
         add_bypass_address(&rl->spec.bypass, rl->rgi.gateway.addr);

 #endif

         /* block access to local subnet */
         add_block_local_item(rl, &rl->rgi.gateway, rl->spec.remote_endpoint);

         /* process additional subnets on gateway interface */
         for (i = 0; i < rl->rgi.n_addrs; ++i)
         {
             const struct route_gateway_address *gwa = &rl->rgi.addrs[i];
             /* omit the add/subnet in &rl->rgi which we processed above */
             if (!((rl->rgi.gateway.addr & rl->rgi.gateway.netmask) == (gwa->addr & gwa->netmask)
                   && rl->rgi.gateway.netmask == gwa->netmask))
             {
                 add_block_local_item(rl, gwa, rl->spec.remote_endpoint);
             }
         }

     }
 }
 

 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.flags |= RTSA_REMOTE_HOST;

     }
 

     if (default_metric)

     {

         rl->spec.default_metric = default_metric;
         rl->spec.flags |= RTSA_DEFAULT_METRIC;

     }
 

     get_default_gateway(&rl->rgi);
     if (rl->rgi.flags & RGI_ADDR_DEFINED)

     {

         setenv_route_addr(es, "net_gateway", rl->rgi.gateway.addr, -1);

 #if defined(ENABLE_DEBUG) && !defined(ENABLE_SMALL)

         print_default_gateway(D_ROUTE, &rl->rgi, NULL);

 #endif

     }

     else

     {

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

     }

     if (rl->spec.flags & RTSA_REMOTE_HOST)

     {

         rl->spec.remote_host_local = test_local_addr(remote_host, &rl->rgi);
     }

     if (is_route_parm_defined(remote_endpoint))
     {
         bool defined = false;
         rl->spec.remote_endpoint = getaddr(
             GETADDR_RESOLVE
             | GETADDR_HOST_ORDER
             | GETADDR_WARN_ON_SIGNAL,
             remote_endpoint,
             0,
             &defined,
             NULL);
 
         if (defined)
         {
             setenv_route_addr(es, "vpn_gateway", rl->spec.remote_endpoint, -1);
             rl->spec.flags |= RTSA_REMOTE_ENDPOINT;
         }
         else
         {
             msg(M_WARN, PACKAGE_NAME " ROUTE: failed to parse/resolve default gateway: %s",
                 remote_endpoint);
             ret = false;
         }

     }

     if (rl->flags & RG_ENABLE)

     {

         add_block_local(rl);
         get_bypass_addresses(&rl->spec.bypass, rl->flags);

 #ifdef ENABLE_DEBUG

         print_bypass_addresses(&rl->spec.bypass);

 #endif
     }

     /* parse the routes from opt to rl */
     {
         struct route_option *ro;
         for (ro = opt->routes; ro; ro = ro->next)
         {
             struct addrinfo *netlist = NULL;
             struct route_ipv4 r;
 
             if (!init_route(&r, &netlist, ro, rl))
             {
                 ret = false;
             }
             else
             {
                 struct addrinfo *curele;
                 for (curele = netlist; curele; curele = curele->ai_next)
                 {
                     struct route_ipv4 *new;
                     ALLOC_OBJ_GC(new, struct route_ipv4, &rl->gc);
                     *new = r;
                     new->network = ntohl(((struct sockaddr_in *)curele->ai_addr)->sin_addr.s_addr);
                     new->next = rl->routes;
                     rl->routes = new;
                 }
             }
             if (netlist)
             {
                 gc_addspecial(netlist, &gc_freeaddrinfo_callback, &gc);
             }
         }
     }
 
     gc_free(&gc);
     return ret;

 }
 

 /* check whether an IPv6 host address is covered by a given route_ipv6
  * (not the most beautiful implementation in the world, but portable and
  * "good enough")
  */
 static bool
 route_ipv6_match_host( const struct route_ipv6 *r6,

                        const struct in6_addr *host )

 {
     unsigned int bits = r6->netbits;
     int i;
     unsigned int mask;
 

     if (bits>128)
     {
         return false;
     }

     for (i = 0; bits >= 8; i++, bits -= 8)

     {

         if (r6->network.s6_addr[i] != host->s6_addr[i])
         {
             return false;
         }

     }
 

     if (bits == 0)
     {
         return true;
     }

 
     mask = 0xff << (8-bits);
 
     if ( (r6->network.s6_addr[i] & mask) == (host->s6_addr[i] & mask ))

     {
         return true;
     }

 
     return false;
 }
 

 bool

 init_route_ipv6_list(struct route_ipv6_list *rl6,
                      const struct route_ipv6_option_list *opt6,
                      const char *remote_endpoint,
                      int default_metric,
                      const struct in6_addr *remote_host_ipv6,
                      struct env_set *es)

 {

     struct gc_arena gc = gc_new();
     bool ret = true;
     bool need_remote_ipv6_route;

     clear_route_ipv6_list(rl6);

     rl6->flags = opt6->flags;

     if (remote_host_ipv6)

     {

         rl6->remote_host_ipv6 = *remote_host_ipv6;
         rl6->spec_flags |= RTSA_REMOTE_HOST;

     }
 

     if (default_metric >= 0)

     {

         rl6->default_metric = default_metric;
         rl6->spec_flags |= RTSA_DEFAULT_METRIC;

     }
 

     msg(D_ROUTE, "GDG6: remote_host_ipv6=%s",
         remote_host_ipv6 ?  print_in6_addr(*remote_host_ipv6, 0, &gc) : "n/a" );

     get_default_gateway_ipv6(&rl6->rgi6, remote_host_ipv6);
     if (rl6->rgi6.flags & RGI_ADDR_DEFINED)

     {

         setenv_str(es, "net_gateway_ipv6", print_in6_addr(rl6->rgi6.gateway.addr_ipv6, 0, &gc));

 #if defined(ENABLE_DEBUG) && !defined(ENABLE_SMALL)

         print_default_gateway(D_ROUTE, NULL, &rl6->rgi6);

 #endif
     }

     else

     {

         dmsg(D_ROUTE, "ROUTE6: default_gateway=UNDEF");

     }
 

     if (is_route_parm_defined( remote_endpoint ))

     {

         if (inet_pton( AF_INET6, remote_endpoint,
                        &rl6->remote_endpoint_ipv6) == 1)
         {
             rl6->spec_flags |= RTSA_REMOTE_ENDPOINT;
         }
         else

         {

             msg(M_WARN, PACKAGE_NAME " ROUTE: failed to parse/resolve VPN endpoint: %s", remote_endpoint);
             ret = false;

         }
     }
 

     /* parse the routes from opt6 to rl6
      * discovering potential overlaps with remote_host_ipv6 in the process
      */
     need_remote_ipv6_route = false;

     {
         struct route_ipv6_option *ro6;
         for (ro6 = opt6->routes_ipv6; ro6; ro6 = ro6->next)
         {
             struct route_ipv6 *r6;
             ALLOC_OBJ_GC(r6, struct route_ipv6, &rl6->gc);
             if (!init_route_ipv6(r6, ro6, rl6))
             {
                 ret = false;
             }
             else
             {
                 r6->next = rl6->routes_ipv6;
                 rl6->routes_ipv6 = r6;

 #ifndef TARGET_ANDROID

                 /* On Android the VPNService protect function call will take of
                  * avoiding routing loops, so ignore this part and let
                  * need_remote_ipv6_route always evaluate to false
                  */
                 if (remote_host_ipv6
                     && route_ipv6_match_host( r6, remote_host_ipv6 ) )
                 {
                     need_remote_ipv6_route = true;
                     msg(D_ROUTE, "ROUTE6: %s/%d overlaps IPv6 remote %s, adding host route to VPN endpoint",
                         print_in6_addr(r6->network, 0, &gc), r6->netbits,
                         print_in6_addr(*remote_host_ipv6, 0, &gc));
                 }

 #endif

             }
         }
     }

     /* add VPN server host route if needed */
     if (need_remote_ipv6_route)

     {

         if ( (rl6->rgi6.flags & (RGI_ADDR_DEFINED|RGI_IFACE_DEFINED) ) ==
              (RGI_ADDR_DEFINED|RGI_IFACE_DEFINED) )

         {

             struct route_ipv6 *r6;
             ALLOC_OBJ_CLEAR_GC(r6, struct route_ipv6, &rl6->gc);
 
             r6->network = *remote_host_ipv6;
             r6->netbits = 128;
             if (!(rl6->rgi6.flags & RGI_ON_LINK) )
             {
                 r6->gateway = rl6->rgi6.gateway.addr_ipv6;
             }
             r6->metric = 1;

 #ifdef _WIN32

             r6->adapter_index = rl6->rgi6.adapter_index;

 #else

             r6->iface = rl6->rgi6.iface;

 #endif

             r6->flags = RT_DEFINED | RT_METRIC_DEFINED;

             r6->next = rl6->routes_ipv6;
             rl6->routes_ipv6 = r6;
         }
         else

         {

             msg(M_WARN, "ROUTE6: IPv6 route overlaps with IPv6 remote address, but could not determine IPv6 gateway address + interface, expect failure\n" );
         }

     }
 

     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 route_gateway_info *rgi,
            const struct env_set *es)
 {
     struct route_ipv4 r;
     CLEAR(r);
     r.flags = RT_DEFINED;
     r.network = network;
     r.netmask = netmask;
     r.gateway = gateway;
     add_route(&r, tt, flags, rgi, 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 route_gateway_info *rgi,
            const struct env_set *es)
 {
     struct route_ipv4 r;
     CLEAR(r);
     r.flags = RT_DEFINED|RT_ADDED;
     r.network = network;
     r.netmask = netmask;
     r.gateway = gateway;
     delete_route(&r, tt, flags, rgi, es);

 }
 
 static void

 add_bypass_routes(struct route_bypass *rb,
                   in_addr_t gateway,
                   const struct tuntap *tt,
                   unsigned int flags,
                   const struct route_gateway_info *rgi,
                   const struct env_set *es)

 {

     int i;
     for (i = 0; i < rb->n_bypass; ++i)

     {

         if (rb->bypass[i])
         {
             add_route3(rb->bypass[i],
                        IPV4_NETMASK_HOST,
                        gateway,
                        tt,
                        flags | ROUTE_REF_GW,
                        rgi,
                        es);
         }

     }
 }
 
 static void

 del_bypass_routes(struct route_bypass *rb,
                   in_addr_t gateway,
                   const struct tuntap *tt,
                   unsigned int flags,
                   const struct route_gateway_info *rgi,
                   const struct env_set *es)

 {

     int i;
     for (i = 0; i < rb->n_bypass; ++i)

     {

         if (rb->bypass[i])
         {
             del_route3(rb->bypass[i],
                        IPV4_NETMASK_HOST,
                        gateway,
                        tt,
                        flags | ROUTE_REF_GW,
                        rgi,
                        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 && rl->flags & RG_ENABLE)
     {

         bool local = rl->flags & RG_LOCAL;
 

         if (!(rl->spec.flags & RTSA_REMOTE_ENDPOINT) && (rl->flags & RG_REROUTE_GW))
         {
             msg(M_WARN, "%s VPN gateway parameter (--route-gateway or --ifconfig) is missing", err);
         }

         /*
          * check if a default route is defined, unless:
          * - we are connecting to a remote host in our network
          * - we are connecting to a non-IPv4 remote host (i.e. we use IPv6)
          */
         else if (!(rl->rgi.flags & RGI_ADDR_DEFINED) && !local
                  && (rl->spec.remote_host != IPV4_INVALID_ADDR))

         {
             msg(M_WARN, "%s Cannot read current default gateway from system", err);
         }
         else if (!(rl->spec.flags & RTSA_REMOTE_HOST))
         {
             msg(M_WARN, "%s Cannot obtain current remote host address", err);
         }
         else
         {
 #ifndef TARGET_ANDROID
             if (rl->flags & RG_AUTO_LOCAL)
             {
                 const int tla = rl->spec.remote_host_local;
                 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 */
                 /* if remote_host is not ipv4 (ie: ipv6), just skip
                  * adding this special /32 route */
                 if (rl->spec.remote_host != IPV4_INVALID_ADDR)
                 {
                     add_route3(rl->spec.remote_host,
                                IPV4_NETMASK_HOST,
                                rl->rgi.gateway.addr,
                                tt,
                                flags | ROUTE_REF_GW,
                                &rl->rgi,
                                es);
                     rl->iflags |= RL_DID_LOCAL;
                 }
                 else
                 {
                     dmsg(D_ROUTE, "ROUTE remote_host protocol differs from tunneled");
                 }
             }
 #endif /* ifndef TARGET_ANDROID */
 
             /* route DHCP/DNS server traffic through original default gateway */
             add_bypass_routes(&rl->spec.bypass, rl->rgi.gateway.addr, tt, flags, &rl->rgi, 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,
                                &rl->rgi,
                                es);
 
                     /* add new default route (2nd component) */
                     add_route3(0x80000000,
                                0x80000000,
                                rl->spec.remote_endpoint,
                                tt,
                                flags,
                                &rl->rgi,
                                es);
                 }
                 else
                 {

                     /* don't try to remove the def route if it does not exist */
                     if (rl->rgi.flags & RGI_ADDR_DEFINED)
                     {
                         /* delete default route */
                         del_route3(0, 0, rl->rgi.gateway.addr, tt,
                                    flags | ROUTE_REF_GW, &rl->rgi, es);
                     }

 
                     /* add new default route */
                     add_route3(0,
                                0,
                                rl->spec.remote_endpoint,
                                tt,
                                flags,
                                &rl->rgi,
                                es);
                 }
             }
 
             /* set a flag so we can undo later */
             rl->iflags |= RL_DID_REDIRECT_DEFAULT_GATEWAY;
         }

     }
 }
 
 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 && rl->iflags & RL_DID_REDIRECT_DEFAULT_GATEWAY)
     {
         /* delete remote host route */
         if (rl->iflags & RL_DID_LOCAL)
         {
             del_route3(rl->spec.remote_host,
                        IPV4_NETMASK_HOST,
                        rl->rgi.gateway.addr,
                        tt,
                        flags | ROUTE_REF_GW,
                        &rl->rgi,
                        es);
             rl->iflags &= ~RL_DID_LOCAL;
         }
 
         /* delete special DHCP/DNS bypass route */
         del_bypass_routes(&rl->spec.bypass, rl->rgi.gateway.addr, tt, flags, &rl->rgi, 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,
                            &rl->rgi,
                            es);
 
                 /* delete default route (2nd component) */
                 del_route3(0x80000000,
                            0x80000000,
                            rl->spec.remote_endpoint,
                            tt,
                            flags,
                            &rl->rgi,
                            es);
             }
             else
             {
                 /* delete default route */
                 del_route3(0,
                            0,
                            rl->spec.remote_endpoint,
                            tt,
                            flags,
                            &rl->rgi,
                            es);

                 /* restore original default route if there was any */
                 if (rl->rgi.flags & RGI_ADDR_DEFINED)
                 {
                     add_route3(0, 0, rl->rgi.gateway.addr, tt,
                                flags | ROUTE_REF_GW, &rl->rgi, es);
                 }

             }
         }
 
         rl->iflags &= ~RL_DID_REDIRECT_DEFAULT_GATEWAY;

     }
 }
 
 void

 add_routes(struct route_list *rl, struct route_ipv6_list *rl6, const struct tuntap *tt, unsigned int flags, const struct env_set *es)

 {

     redirect_default_route_to_vpn(rl, tt, flags, es);
     if (rl && !(rl->iflags & RL_ROUTES_ADDED) )

     {

         struct route_ipv4 *r;

 
 #ifdef ENABLE_MANAGEMENT

         if (management && rl->routes)
         {
             management_set_state(management,
                                  OPENVPN_STATE_ADD_ROUTES,
                                  NULL,
                                  NULL,
                                  NULL,
                                  NULL,
                                  NULL);
         }

 #endif

         for (r = rl->routes; r; r = r->next)
         {
             check_subnet_conflict(r->network, r->netmask, "route");
             if (flags & ROUTE_DELETE_FIRST)
             {
                 delete_route(r, tt, flags, &rl->rgi, es);
             }
             add_route(r, tt, flags, &rl->rgi, es);
         }
         rl->iflags |= RL_ROUTES_ADDED;

     }

     if (rl6 && !(rl6->iflags & RL_ROUTES_ADDED) )

     {

         struct route_ipv6 *r;

 
         if (!tt->did_ifconfig_ipv6_setup)
         {
             msg(M_INFO, "WARNING: OpenVPN was configured to add an IPv6 "
                 "route over %s. However, no IPv6 has been configured for "
                 "this interface, therefore the route installation may "
                 "fail or may not work as expected.", tt->actual_name);
         }
 

         for (r = rl6->routes_ipv6; r; r = r->next)
         {
             if (flags & ROUTE_DELETE_FIRST)
             {
                 delete_route_ipv6(r, tt, flags, es);
             }
             add_route_ipv6(r, tt, flags, es);
         }
         rl6->iflags |= RL_ROUTES_ADDED;

     }

 }
 
 void

 delete_routes(struct route_list *rl, struct route_ipv6_list *rl6,
               const struct tuntap *tt, unsigned int flags, const struct env_set *es)

 {

     if (rl && rl->iflags & RL_ROUTES_ADDED)

     {

         struct route_ipv4 *r;
         for (r = rl->routes; r; r = r->next)
         {
             delete_route(r, tt, flags, &rl->rgi, es);
         }
         rl->iflags &= ~RL_ROUTES_ADDED;

     }
 

     undo_redirect_default_route_to_vpn(rl, tt, flags, es);

     if (rl)

     {

         clear_route_list(rl);

     }

     if (rl6 && (rl6->iflags & RL_ROUTES_ADDED) )

     {

         struct route_ipv6 *r6;
         for (r6 = rl6->routes_ipv6; r6; r6 = r6->next)
         {
             delete_route_ipv6(r6, tt, flags, es);
         }
         rl6->iflags &= ~RL_ROUTES_ADDED;

     }
 

     if (rl6)

     {

         clear_route_ipv6_list(rl6);

     }

 }
 

 #ifndef ENABLE_SMALL

 
 static const char *

 show_opt(const char *option)

 {

     if (!option)
     {
         return "default (not set)";
     }
     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)

 {

     struct route_option *ro;
     if (rol->flags & RG_ENABLE)
     {
         msg(level, "  [redirect_default_gateway local=%d]",
             (rol->flags & RG_LOCAL) != 0);
     }
     for (ro = rol->routes; ro; ro = ro->next)

     {

         print_route_option(ro, level);

     }

 }
 

 void

 print_default_gateway(const int msglevel,

                       const struct route_gateway_info *rgi,
                       const struct route_ipv6_gateway_info *rgi6)
 {
     struct gc_arena gc = gc_new();
     if (rgi && (rgi->flags & RGI_ADDR_DEFINED))
     {
         struct buffer out = alloc_buf_gc(256, &gc);
         buf_printf(&out, "ROUTE_GATEWAY");
         if (rgi->flags & RGI_ON_LINK)
         {
             buf_printf(&out, " ON_LINK");
         }
         else
         {
             buf_printf(&out, " %s", print_in_addr_t(rgi->gateway.addr, 0, &gc));
         }
         if (rgi->flags & RGI_NETMASK_DEFINED)
         {
             buf_printf(&out, "/%s", print_in_addr_t(rgi->gateway.netmask, 0, &gc));
         }

 #ifdef _WIN32

         if (rgi->flags & RGI_IFACE_DEFINED)
         {

             buf_printf(&out, " I=%lu", rgi->adapter_index);

         }

 #else

         if (rgi->flags & RGI_IFACE_DEFINED)
         {
             buf_printf(&out, " IFACE=%s", rgi->iface);
         }

 #endif

         if (rgi->flags & RGI_HWADDR_DEFINED)
         {
             buf_printf(&out, " HWADDR=%s", format_hex_ex(rgi->hwaddr, 6, 0, 1, ":", &gc));
         }
         msg(msglevel, "%s", BSTR(&out));

     }

     if (rgi6 && (rgi6->flags & RGI_ADDR_DEFINED))

     {

         struct buffer out = alloc_buf_gc(256, &gc);
         buf_printf(&out, "ROUTE6_GATEWAY");
         buf_printf(&out, " %s", print_in6_addr(rgi6->gateway.addr_ipv6, 0, &gc));
         if (rgi6->flags & RGI_ON_LINK)
         {
             buf_printf(&out, " ON_LINK");
         }
         if (rgi6->flags & RGI_NETMASK_DEFINED)
         {
             buf_printf(&out, "/%d", rgi6->gateway.netbits_ipv6);
         }

 #ifdef _WIN32

         if (rgi6->flags & RGI_IFACE_DEFINED)
         {

             buf_printf(&out, " I=%lu", rgi6->adapter_index);

         }

 #else

         if (rgi6->flags & RGI_IFACE_DEFINED)
         {
             buf_printf(&out, " IFACE=%s", rgi6->iface);
         }

 #endif

         if (rgi6->flags & RGI_HWADDR_DEFINED)
         {
             buf_printf(&out, " HWADDR=%s", format_hex_ex(rgi6->hwaddr, 6, 0, 1, ":", &gc));
         }
         msg(msglevel, "%s", BSTR(&out));

     }

     gc_free(&gc);

 }
 

 #endif /* ifndef ENABLE_SMALL */

 
 static void

 print_route(const struct route_ipv4 *r, int level)

 {

     struct gc_arena gc = gc_new();
     if (r->flags & RT_DEFINED)
     {
         msg(level, "%s", route_string(r, &gc));
     }
     gc_free(&gc);

 }
 
 void

 print_routes(const struct route_list *rl, int level)

 {

     struct route_ipv4 *r;
     for (r = rl->routes; r; r = r->next)

     {

         print_route(r, level);

     }

 }
 
 static void

 setenv_route(struct env_set *es, const struct route_ipv4 *r, int i)

 {

     struct gc_arena gc = gc_new();
     if (r->flags & RT_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->flags & RT_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 = 1;
     struct route_ipv4 *r;
     for (r = rl->routes; r; r = r->next)

     {

         setenv_route(es, r, i++);

     }

 }
 

 static void

 setenv_route_ipv6(struct env_set *es, const struct route_ipv6 *r6, int i)

 {

     struct gc_arena gc = gc_new();
     if (r6->flags & RT_DEFINED)

     {

         struct buffer name1 = alloc_buf_gc( 256, &gc );
         struct buffer val = alloc_buf_gc( 256, &gc );
         struct buffer name2 = alloc_buf_gc( 256, &gc );

         buf_printf( &name1, "route_ipv6_network_%d", i );
         buf_printf( &val, "%s/%d", print_in6_addr( r6->network, 0, &gc ),
                     r6->netbits );
         setenv_str( es, BSTR(&name1), BSTR(&val) );

         buf_printf( &name2, "route_ipv6_gateway_%d", i );
         setenv_str( es, BSTR(&name2), print_in6_addr( r6->gateway, 0, &gc ));

     }

     gc_free(&gc);

 }
 void

 setenv_routes_ipv6(struct env_set *es, const struct route_ipv6_list *rl6)

 {

     int i = 1;
     struct route_ipv6 *r6;
     for (r6 = rl6->routes_ipv6; r6; r6 = r6->next)

     {

         setenv_route_ipv6(es, r6, i++);

     }

 }
 

 /*
  * local_route() determines whether the gateway of a provided host
  * route is on the same interface that owns the default gateway.
  * It uses the data structure
  * returned by get_default_gateway() (struct route_gateway_info)
  * to determine this.  If the route is local, LR_MATCH is returned.
  * When adding routes into the kernel, if LR_MATCH is defined for
  * a given route, the route should explicitly reference the default
  * gateway interface as the route destination.  For example, here
  * is an example on Linux that uses LR_MATCH:
  *

  *   route add -net 10.10.0.1 netmask 255.255.255.255 dev eth0

  *
  * This capability is needed by the "default-gateway block-local"
  * directive, to allow client access to the local subnet to be
  * blocked but still allow access to the local default gateway.
  */
 
 /* local_route() return values */
 #define LR_NOMATCH 0 /* route is not local */
 #define LR_MATCH   1 /* route is local */
 #define LR_ERROR   2 /* caller should abort adding route */
 
 static int

 local_route(in_addr_t network,
             in_addr_t netmask,
             in_addr_t gateway,
             const struct route_gateway_info *rgi)
 {
     /* set LR_MATCH on local host routes */
     const int rgi_needed = (RGI_ADDR_DEFINED|RGI_NETMASK_DEFINED|RGI_IFACE_DEFINED);
     if (rgi
         && (rgi->flags & rgi_needed) == rgi_needed
         && gateway == rgi->gateway.addr
         && netmask == 0xFFFFFFFF)
     {
         if (((network ^  rgi->gateway.addr) & rgi->gateway.netmask) == 0)
         {
             return LR_MATCH;
         }
         else
         {
             /* examine additional subnets on gateway interface */
             size_t i;
             for (i = 0; i < rgi->n_addrs; ++i)
             {
                 const struct route_gateway_address *gwa = &rgi->addrs[i];
                 if (((network ^ gwa->addr) & gwa->netmask) == 0)
                 {
                     return LR_MATCH;
                 }
             }
         }

     }
     return LR_NOMATCH;
 }
 

 /* Return true if the "on-link" form of the route should be used.  This is when the gateway for a

  * a route is specified as an interface rather than an address. */

 static inline bool

 is_on_link(const int is_local_route, const unsigned int flags, const struct route_gateway_info *rgi)

 {

     return rgi && (is_local_route == LR_MATCH || ((flags & ROUTE_REF_GW) && (rgi->flags & RGI_ON_LINK)));

 }
 

 void

 add_route(struct route_ipv4 *r,
           const struct tuntap *tt,
           unsigned int flags,
           const struct route_gateway_info *rgi,  /* may be NULL */
           const struct env_set *es)

 {

     struct gc_arena gc;
     struct argv argv = argv_new();
     const char *network;

 #if !defined(ENABLE_IPROUTE) && !defined(TARGET_AIX)

     const char *netmask;

 #endif

     const char *gateway;
     bool status = false;
     int is_local_route;
 
     if (!(r->flags & RT_DEFINED))
     {
         return;
     }

     gc_init(&gc);

     network = print_in_addr_t(r->network, 0, &gc);

 #if !defined(ENABLE_IPROUTE) && !defined(TARGET_AIX)

     netmask = print_in_addr_t(r->netmask, 0, &gc);

 #endif

     gateway = print_in_addr_t(r->gateway, 0, &gc);

     is_local_route = local_route(r->network, r->netmask, r->gateway, rgi);
     if (is_local_route == LR_ERROR)
     {
         goto done;
     }

 
 #if defined(TARGET_LINUX)

 #ifdef ENABLE_IPROUTE

     argv_printf(&argv, "%s route add %s/%d",
                 iproute_path,
                 network,
                 netmask_to_netbits2(r->netmask));
 
     if (r->flags & RT_METRIC_DEFINED)
     {
         argv_printf_cat(&argv, "metric %d", r->metric);
     }
 
     if (is_on_link(is_local_route, flags, rgi))
     {
         argv_printf_cat(&argv, "dev %s", rgi->iface);
     }
     else
     {
         argv_printf_cat(&argv, "via %s", gateway);
     }
 #else  /* ifdef ENABLE_IPROUTE */
     argv_printf(&argv, "%s add -net %s netmask %s",
                 ROUTE_PATH,
                 network,
                 netmask);
     if (r->flags & RT_METRIC_DEFINED)
     {
         argv_printf_cat(&argv, "metric %d", r->metric);
     }
     if (is_on_link(is_local_route, flags, rgi))
     {
         argv_printf_cat(&argv, "dev %s", rgi->iface);
     }
     else
     {
         argv_printf_cat(&argv, "gw %s", gateway);
     }

 #endif  /*ENABLE_IPROUTE*/

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

 #elif defined (TARGET_ANDROID)

     char out[128];

     if (rgi)
     {

         openvpn_snprintf(out, sizeof(out), "%s %s %s dev %s", network, netmask, gateway, rgi->iface);

     }
     else
     {

         openvpn_snprintf(out, sizeof(out), "%s %s %s", network, netmask, gateway);

     }

     management_android_control(management, "ROUTE", out);

 #elif defined (_WIN32)

     {
         DWORD ai = TUN_ADAPTER_INDEX_INVALID;
         argv_printf(&argv, "%s%sc ADD %s MASK %s %s",
                     get_win_sys_path(),
                     WIN_ROUTE_PATH_SUFFIX,
                     network,
                     netmask,
                     gateway);
         if (r->flags & RT_METRIC_DEFINED)
         {
             argv_printf_cat(&argv, "METRIC %d", r->metric);
         }
         if (is_on_link(is_local_route, flags, rgi))
         {
             ai = rgi->adapter_index;

             argv_printf_cat(&argv, "IF %lu", ai);

         }

         argv_msg(D_ROUTE, &argv);

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

     argv_printf_cat(&argv, "%s -netmask %s %s",
                     network,
                     netmask,
                     gateway);

     /* Solaris can only distinguish between "metric 0" == "on-link on the
      * interface where the IP address given is configured" and "metric > 0"
      * == "use gateway specified" (no finer-grained route metrics available)
      *
      * More recent versions of Solaris can also do "-interface", but that
      * would break backwards compatibility with older versions for no gain.
      */
     if (r->flags & RT_METRIC_DEFINED)
     {
         argv_printf_cat(&argv, "%d", r->metric);
     }

     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->flags & RT_METRIC_DEFINED)
     {
         argv_printf_cat(&argv, "-rtt %d", r->metric);
     }

 #endif
 

     argv_printf_cat(&argv, "-net %s %s %s",
                     network,
                     gateway,
                     netmask);

     /* FIXME -- add on-link support for FreeBSD */

     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->flags & RT_METRIC_DEFINED)
     {
         argv_printf_cat(&argv, "-rtt %d", r->metric);
     }

 #endif
 

     argv_printf_cat(&argv, "-net %s %s %s",
                     network,
                     gateway,
                     netmask);

     /* FIXME -- add on-link support for Dragonfly */

     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->flags & RT_METRIC_DEFINED)
     {
         argv_printf_cat(&argv, "-rtt %d", r->metric);
     }

 #endif
 

     if (is_on_link(is_local_route, flags, rgi))

     {

         /* Mac OS X route syntax for ON_LINK:
          * route add -cloning -net 10.10.0.1 -netmask 255.255.255.255 -interface en0 */
         argv_printf_cat(&argv, "-cloning -net %s -netmask %s -interface %s",
                         network,
                         netmask,
                         rgi->iface);

     }

     else

     {

         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->flags & RT_METRIC_DEFINED)
     {
         argv_printf_cat(&argv, "-rtt %d", r->metric);
     }

 #endif
 

     argv_printf_cat(&argv, "-net %s %s -netmask %s",
                     network,
                     gateway,
                     netmask);

     /* FIXME -- add on-link support for OpenBSD/NetBSD */

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

 #elif defined(TARGET_AIX)
 

     {
         int netbits = netmask_to_netbits2(r->netmask);
         argv_printf(&argv, "%s add -net %s/%d %s",
                     ROUTE_PATH,
                     network, netbits, gateway);
         argv_msg(D_ROUTE, &argv);
         status = openvpn_execve_check(&argv, es, 0, "ERROR: AIX route add command failed");
     }

 #else  /* if defined(TARGET_LINUX) */
     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 /* if defined(TARGET_LINUX) */

 done:
     if (status)
     {
         r->flags |= RT_ADDED;
     }
     else
     {
         r->flags &= ~RT_ADDED;
     }
     argv_reset(&argv);
     gc_free(&gc);

 }
 

 void

 route_ipv6_clear_host_bits( struct route_ipv6 *r6 )

 {

     /* clear host bit parts of route
      * (needed if routes are specified improperly, or if we need to
      * explicitely setup/clear the "connected" network routes on some OSes)
      */
     int byte = 15;
     int bits_to_clear = 128 - r6->netbits;

     while (byte >= 0 && bits_to_clear > 0)

     {

         if (bits_to_clear >= 8)
         {
             r6->network.s6_addr[byte--] = 0; bits_to_clear -= 8;
         }
         else
         {
             r6->network.s6_addr[byte--] &= (0xff << bits_to_clear); bits_to_clear = 0;
         }

     }
 }
 

 void

 add_route_ipv6(struct route_ipv6 *r6, const struct tuntap *tt, unsigned int flags, const struct env_set *es)

 {

     struct gc_arena gc;
     struct argv argv = argv_new();

     const char *network;
     const char *gateway;
     bool status = false;
     const char *device = tt->actual_name;

     bool gateway_needed = false;

     if (!(r6->flags & RT_DEFINED) )
     {
         return;
     }

 #ifndef _WIN32

     if (r6->iface != NULL)              /* vpn server special route */

     {

         device = r6->iface;
         if (!IN6_IS_ADDR_UNSPECIFIED(&r6->gateway) )
         {
             gateway_needed = true;
         }

     }
 #endif
 

     gc_init(&gc);

     route_ipv6_clear_host_bits(r6);

     network = print_in6_addr( r6->network, 0, &gc);
     gateway = print_in6_addr( r6->gateway, 0, &gc);

 #if defined(TARGET_DARWIN)    \
     || defined(TARGET_FREEBSD) || defined(TARGET_DRAGONFLY)    \
     || defined(TARGET_OPENBSD) || defined(TARGET_NETBSD)

     /* the BSD platforms cannot specify gateway and interface independently,
      * but for link-local destinations, we MUST specify the interface, so
      * we build a combined "$gateway%$interface" gateway string
      */
     if (r6->iface != NULL && gateway_needed
         && IN6_IS_ADDR_LINKLOCAL(&r6->gateway) )        /* fe80::...%intf */

     {

         int len = strlen(gateway) + 1 + strlen(r6->iface)+1;
         char *tmp = gc_malloc( len, true, &gc );
         snprintf( tmp, len, "%s%%%s", gateway, r6->iface );
         gateway = tmp;

     }
 #endif
 

     msg( M_INFO, "add_route_ipv6(%s/%d -> %s metric %d) dev %s",
          network, r6->netbits, gateway, r6->metric, device );

     /*
      * Filter out routes which are essentially no-ops
      * (not currently done for IPv6)
      */

     /* On "tun" interface, we never set a gateway if the operating system
      * can do "route to interface" - it does not add value, as the target
      * dev already fully qualifies the route destination on point-to-point
      * interfaces.   OTOH, on "tap" interface, we must always set the
      * gateway unless the route is to be an on-link network
      */
     if (tt->type == DEV_TYPE_TAP
         && !( (r6->flags & RT_METRIC_DEFINED) && r6->metric == 0 ) )

     {

         gateway_needed = true;

     }
 

 #if defined(TARGET_LINUX)

 #ifdef ENABLE_IPROUTE

     argv_printf(&argv, "%s -6 route add %s/%d dev %s",
                 iproute_path,
                 network,
                 r6->netbits,
                 device);
     if (gateway_needed)
     {
         argv_printf_cat(&argv, "via %s", gateway);
     }
     if ( (r6->flags & RT_METRIC_DEFINED) && r6->metric > 0)
     {
         argv_printf_cat(&argv, " metric %d", r6->metric);
     }

 #else  /* ifdef ENABLE_IPROUTE */
     argv_printf(&argv, "%s -A inet6 add %s/%d dev %s",
                 ROUTE_PATH,
                 network,
                 r6->netbits,
                 device);
     if (gateway_needed)
     {
         argv_printf_cat(&argv, "gw %s", gateway);
     }
     if ( (r6->flags & RT_METRIC_DEFINED) && r6->metric > 0)
     {
         argv_printf_cat(&argv, " metric %d", r6->metric);
     }

 #endif  /*ENABLE_IPROUTE*/

     argv_msg(D_ROUTE, &argv);
     status = openvpn_execve_check(&argv, es, 0, "ERROR: Linux route -6/-A inet6 add command failed");

 #elif defined (TARGET_ANDROID)

     char out[64];

     openvpn_snprintf(out, sizeof(out), "%s/%d %s", network, r6->netbits, device);

     management_android_control(management, "ROUTE6", out);

 #elif defined (_WIN32)

     if (tt->options.msg_channel)
     {
         status = add_route_ipv6_service(r6, tt);
     }
     else
     {
         struct buffer out = alloc_buf_gc(64, &gc);
         if (r6->adapter_index)          /* vpn server special route */
         {

             buf_printf(&out, "interface=%lu", r6->adapter_index );

             gateway_needed = true;
         }
         else
         {

             buf_printf(&out, "interface=%lu", tt->adapter_index );

         }
         device = buf_bptr(&out);
 
         /* netsh interface ipv6 add route 2001:db8::/32 MyTunDevice */
         argv_printf(&argv, "%s%sc interface ipv6 add route %s/%d %s",
                     get_win_sys_path(),
                     NETSH_PATH_SUFFIX,
                     network,
                     r6->netbits,
                     device);
 
         /* next-hop depends on TUN or TAP mode:
          * - in TAP mode, we use the "real" next-hop
          * - in TUN mode we use a special-case link-local address that the tapdrvr
          *   knows about and will answer ND (neighbor discovery) packets for
          */
         if (tt->type == DEV_TYPE_TUN && !gateway_needed)
         {
             argv_printf_cat( &argv, " %s", "fe80::8" );
         }
         else if (!IN6_IS_ADDR_UNSPECIFIED(&r6->gateway) )
         {
             argv_printf_cat( &argv, " %s", gateway );
         }

 #if 0

         if (r6->flags & RT_METRIC_DEFINED)
         {
             argv_printf_cat(&argv, " METRIC %d", r->metric);
         }

 #endif
 

         /* in some versions of Windows, routes are persistent across reboots by
          * default, unless "store=active" is set (pointed out by Tony Lim, thanks)
          */
         argv_printf_cat( &argv, " store=active" );

         argv_msg(D_ROUTE, &argv);

         netcmd_semaphore_lock();
         status = openvpn_execve_check(&argv, es, 0, "ERROR: Windows route add ipv6 command failed");
         netcmd_semaphore_release();

     }

 
 #elif defined (TARGET_SOLARIS)
 

     /* example: route add -inet6 2001:db8::/32 somegateway 0 */
 
     /* for some reason, routes to tun/tap do not work for me unless I set
      * "metric 0" - otherwise, the routes will be nicely installed, but
      * packets will just disappear somewhere.  So we always use "0" now,
      * unless the route points to "gateway on other interface"...
      *
      * (Note: OpenSolaris can not specify host%interface gateways, so we just
      * use the GW addresses - it seems to still work for fe80:: addresses,
      * however this is done internally.  NUD maybe?)
      */
     argv_printf(&argv, "%s add -inet6 %s/%d %s",
                 ROUTE_PATH,
                 network,
                 r6->netbits,
                 gateway );
 
     /* on tun/tap, not "elsewhere"? -> metric 0 */
     if (!r6->iface)
     {
         argv_printf_cat(&argv, "0");
     }
 
     argv_msg(D_ROUTE, &argv);
     status = openvpn_execve_check(&argv, es, 0, "ERROR: Solaris route add -inet6 command failed");

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

     argv_printf(&argv, "%s add -inet6 %s/%d",
                 ROUTE_PATH,
                 network,
                 r6->netbits);

     if (gateway_needed)
     {
         argv_printf_cat(&argv, "%s", gateway);
     }
     else
     {
         argv_printf_cat(&argv, "-iface %s", device);
     }

     argv_msg(D_ROUTE, &argv);
     status = openvpn_execve_check(&argv, es, 0, "ERROR: *BSD route add -inet6 command failed");

 #elif defined(TARGET_DARWIN)

     argv_printf(&argv, "%s add -inet6 %s -prefixlen %d",
                 ROUTE_PATH,
                 network, r6->netbits );

     if (gateway_needed)
     {
         argv_printf_cat(&argv, "%s", gateway);
     }
     else
     {
         argv_printf_cat(&argv, "-iface %s", device);
     }

     argv_msg(D_ROUTE, &argv);
     status = openvpn_execve_check(&argv, es, 0, "ERROR: MacOS X route add -inet6 command failed");

 #elif defined(TARGET_OPENBSD)

     argv_printf(&argv, "%s add -inet6 %s -prefixlen %d %s",
                 ROUTE_PATH,
                 network, r6->netbits, gateway );

     argv_msg(D_ROUTE, &argv);
     status = openvpn_execve_check(&argv, es, 0, "ERROR: OpenBSD route add -inet6 command failed");

 
 #elif defined(TARGET_NETBSD)

     argv_printf(&argv, "%s add -inet6 %s/%d %s",
                 ROUTE_PATH,
                 network, r6->netbits, gateway );

     argv_msg(D_ROUTE, &argv);
     status = openvpn_execve_check(&argv, es, 0, "ERROR: NetBSD route add -inet6 command failed");

 #elif defined(TARGET_AIX)
 

     argv_printf(&argv, "%s add -inet6 %s/%d %s",
                 ROUTE_PATH,
                 network, r6->netbits, gateway);
     argv_msg(D_ROUTE, &argv);
     status = openvpn_execve_check(&argv, es, 0, "ERROR: AIX route add command failed");

 #else  /* if defined(TARGET_LINUX) */
     msg(M_FATAL, "Sorry, but I don't know how to do 'route ipv6' commands on this operating system.  Try putting your routes in a --route-up script");
 #endif /* if defined(TARGET_LINUX) */

     if (status)
     {
         r6->flags |= RT_ADDED;
     }
     else
     {
         r6->flags &= ~RT_ADDED;
     }
     argv_reset(&argv);
     gc_free(&gc);

 }
 

 static void

 delete_route(struct route_ipv4 *r,
              const struct tuntap *tt,
              unsigned int flags,
              const struct route_gateway_info *rgi,
              const struct env_set *es)

 {

     struct gc_arena gc;
     struct argv argv = argv_new();
     const char *network;

 #if !defined(ENABLE_IPROUTE) && !defined(TARGET_AIX)

     const char *netmask;

 #endif
 #if !defined(TARGET_LINUX) && !defined(TARGET_ANDROID)

     const char *gateway;

 #endif

     int is_local_route;
 
     if ((r->flags & (RT_DEFINED|RT_ADDED)) != (RT_DEFINED|RT_ADDED))
     {
         return;
     }

     gc_init(&gc);

     network = print_in_addr_t(r->network, 0, &gc);

 #if !defined(ENABLE_IPROUTE) && !defined(TARGET_AIX)

     netmask = print_in_addr_t(r->netmask, 0, &gc);

 #endif
 #if !defined(TARGET_LINUX) && !defined(TARGET_ANDROID)

     gateway = print_in_addr_t(r->gateway, 0, &gc);

 #endif

     is_local_route = local_route(r->network, r->netmask, r->gateway, rgi);
     if (is_local_route == LR_ERROR)
     {
         goto done;
     }

 #if defined(TARGET_LINUX)

 #ifdef ENABLE_IPROUTE

     argv_printf(&argv, "%s route del %s/%d",
                 iproute_path,
                 network,
                 netmask_to_netbits2(r->netmask));

 #else

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

 #endif /*ENABLE_IPROUTE*/

     if (r->flags & RT_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_SERVICE)

     {

         const bool status = del_route_service(r, tt);
         msg(D_ROUTE, "Route deletion via service %s", status ? "succeeded" : "failed");

     }

     else 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)
 

     if (is_on_link(is_local_route, flags, rgi))

     {

         argv_printf(&argv, "%s delete -cloning -net %s -netmask %s -interface %s",
                     ROUTE_PATH,
                     network,
                     netmask,
                     rgi->iface);

     }

     else

     {

         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");

 #elif defined(TARGET_ANDROID)

     msg(M_NONFATAL, "Sorry, deleting routes on Android is not possible. The VpnService API allows routes to be set on connect only.");

 
 #elif defined(TARGET_AIX)
 

     {
         int netbits = netmask_to_netbits2(r->netmask);
         argv_printf(&argv, "%s delete -net %s/%d %s",
                     ROUTE_PATH,
                     network, netbits, gateway);
         argv_msg(D_ROUTE, &argv);
         openvpn_execve_check(&argv, es, 0, "ERROR: AIX route delete command failed");
     }

 #else  /* if defined(TARGET_LINUX) */
     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 /* if defined(TARGET_LINUX) */

 done:
     r->flags &= ~RT_ADDED;
     argv_reset(&argv);
     gc_free(&gc);

 }
 

 void

 delete_route_ipv6(const struct route_ipv6 *r6, const struct tuntap *tt, unsigned int flags, const struct env_set *es)

 {

     struct gc_arena gc;
     struct argv argv = argv_new();
     const char *network;
     const char *gateway;
     const char *device = tt->actual_name;
     bool gateway_needed = false;
 
     if ((r6->flags & (RT_DEFINED|RT_ADDED)) != (RT_DEFINED|RT_ADDED))
     {
         return;
     }

 #ifndef _WIN32

     if (r6->iface != NULL)              /* vpn server special route */

     {

         device = r6->iface;
         gateway_needed = true;

     }
 #endif
 

     gc_init(&gc);

     network = print_in6_addr( r6->network, 0, &gc);
     gateway = print_in6_addr( r6->gateway, 0, &gc);

 #if defined(TARGET_DARWIN)    \
     || defined(TARGET_FREEBSD) || defined(TARGET_DRAGONFLY)    \
     || defined(TARGET_OPENBSD) || defined(TARGET_NETBSD)

     /* the BSD platforms cannot specify gateway and interface independently,
      * but for link-local destinations, we MUST specify the interface, so
      * we build a combined "$gateway%$interface" gateway string
      */
     if (r6->iface != NULL && gateway_needed
         && IN6_IS_ADDR_LINKLOCAL(&r6->gateway) )        /* fe80::...%intf */

     {

         int len = strlen(gateway) + 1 + strlen(r6->iface)+1;
         char *tmp = gc_malloc( len, true, &gc );
         snprintf( tmp, len, "%s%%%s", gateway, r6->iface );
         gateway = tmp;

     }
 #endif
 

     msg( M_INFO, "delete_route_ipv6(%s/%d)", network, r6->netbits );

     /* if we used a gateway on "add route", we also need to specify it on
      * delete, otherwise some OSes will refuse to delete the route
      */
     if (tt->type == DEV_TYPE_TAP
         && !( (r6->flags & RT_METRIC_DEFINED) && r6->metric == 0 ) )

     {

         gateway_needed = true;

     }
 
 

 #if defined(TARGET_LINUX)

 #ifdef ENABLE_IPROUTE

     argv_printf(&argv, "%s -6 route del %s/%d dev %s",
                 iproute_path,
                 network,
                 r6->netbits,
                 device);
     if (gateway_needed)
     {
         argv_printf_cat(&argv, "via %s", gateway);
     }
 #else  /* ifdef ENABLE_IPROUTE */
     argv_printf(&argv, "%s -A inet6 del %s/%d dev %s",
                 ROUTE_PATH,
                 network,
                 r6->netbits,
                 device);
     if (gateway_needed)
     {
         argv_printf_cat(&argv, "gw %s", gateway);
     }
     if ( (r6->flags & RT_METRIC_DEFINED) && r6->metric > 0)
     {
         argv_printf_cat(&argv, " metric %d", r6->metric);
     }

 #endif  /*ENABLE_IPROUTE*/

     argv_msg(D_ROUTE, &argv);
     openvpn_execve_check(&argv, es, 0, "ERROR: Linux route -6/-A inet6 del command failed");

 #elif defined (_WIN32)

     if (tt->options.msg_channel)
     {
         del_route_ipv6_service(r6, tt);
     }
     else
     {
         struct buffer out = alloc_buf_gc(64, &gc);
         if (r6->adapter_index)          /* vpn server special route */
         {

             buf_printf(&out, "interface=%lu", r6->adapter_index );

             gateway_needed = true;
         }
         else
         {

             buf_printf(&out, "interface=%lu", tt->adapter_index );

         }
         device = buf_bptr(&out);
 
         /* netsh interface ipv6 delete route 2001:db8::/32 MyTunDevice */
         argv_printf(&argv, "%s%sc interface ipv6 delete route %s/%d %s",
                     get_win_sys_path(),
                     NETSH_PATH_SUFFIX,
                     network,
                     r6->netbits,
                     device);
 
         /* next-hop depends on TUN or TAP mode:
          * - in TAP mode, we use the "real" next-hop
          * - in TUN mode we use a special-case link-local address that the tapdrvr
          *   knows about and will answer ND (neighbor discovery) packets for
          * (and "route deletion without specifying next-hop" does not work...)
          */
         if (tt->type == DEV_TYPE_TUN && !gateway_needed)
         {
             argv_printf_cat( &argv, " %s", "fe80::8" );
         }
         else if (!IN6_IS_ADDR_UNSPECIFIED(&r6->gateway) )
         {
             argv_printf_cat( &argv, " %s", gateway );
         }

 #if 0

         if (r6->flags & RT_METRIC_DEFINED)
         {
             argv_printf_cat(&argv, "METRIC %d", r->metric);
         }

 #endif
 

         /* Windows XP to 7 "just delete" routes, wherever they came from, but
          * in Windows 8(.1?), if you create them with "store=active", this is
          * how you should delete them as well (pointed out by Cedric Tabary)
          */
         argv_printf_cat( &argv, " store=active" );

         argv_msg(D_ROUTE, &argv);

         netcmd_semaphore_lock();
         openvpn_execve_check(&argv, es, 0, "ERROR: Windows route delete ipv6 command failed");
         netcmd_semaphore_release();

     }

 
 #elif defined (TARGET_SOLARIS)
 

     /* example: route delete -inet6 2001:db8::/32 somegateway */

     argv_printf(&argv, "%s delete -inet6 %s/%d %s",
                 ROUTE_PATH,
                 network,
                 r6->netbits,
                 gateway );

     argv_msg(D_ROUTE, &argv);
     openvpn_execve_check(&argv, es, 0, "ERROR: Solaris route delete -inet6 command failed");

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

     argv_printf(&argv, "%s delete -inet6 %s/%d",
                 ROUTE_PATH,
                 network,
                 r6->netbits );

     if (gateway_needed)
     {
         argv_printf_cat(&argv, "%s", gateway);
     }
     else
     {
         argv_printf_cat(&argv, "-iface %s", device);
     }

     argv_msg(D_ROUTE, &argv);
     openvpn_execve_check(&argv, es, 0, "ERROR: *BSD route delete -inet6 command failed");

 #elif defined(TARGET_DARWIN)

     argv_printf(&argv, "%s delete -inet6 %s -prefixlen %d",
                 ROUTE_PATH,
                 network, r6->netbits );

     if (gateway_needed)
     {
         argv_printf_cat(&argv, "%s", gateway);
     }
     else
     {
         argv_printf_cat(&argv, "-iface %s", device);
     }

     argv_msg(D_ROUTE, &argv);
     openvpn_execve_check(&argv, es, 0, "ERROR: MacOS X route delete -inet6 command failed");

 #elif defined(TARGET_OPENBSD)

     argv_printf(&argv, "%s delete -inet6 %s -prefixlen %d %s",
                 ROUTE_PATH,
                 network, r6->netbits, gateway );

     argv_msg(D_ROUTE, &argv);
     openvpn_execve_check(&argv, es, 0, "ERROR: OpenBSD route delete -inet6 command failed");

 
 #elif defined(TARGET_NETBSD)

     argv_printf(&argv, "%s delete -inet6 %s/%d %s",
                 ROUTE_PATH,
                 network, r6->netbits, gateway );

     argv_msg(D_ROUTE, &argv);
     openvpn_execve_check(&argv, es, 0, "ERROR: NetBSD route delete -inet6 command failed");

 #elif defined(TARGET_AIX)
 

     argv_printf(&argv, "%s delete -inet6 %s/%d %s",
                 ROUTE_PATH,
                 network, r6->netbits, gateway);
     argv_msg(D_ROUTE, &argv);
     openvpn_execve_check(&argv, es, 0, "ERROR: AIX route add command failed");

 #else  /* if defined(TARGET_LINUX) */
     msg(M_FATAL, "Sorry, but I don't know how to do 'route ipv6' commands on this operating system.  Try putting your routes in a --route-down script");
 #endif /* if defined(TARGET_LINUX) */

     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;
     int len = -1;
     bool adapter_up = false;
 
     if (is_adapter_up(tt, adapters))

     {

         ret = true;
         adapter_up = true;

         /* we do this test only if we have IPv4 routes to install, and if
          * the tun/tap interface has seen IPv4 ifconfig - because if we
          * have no IPv4, the check will always fail, failing tun init
          */
         if (rl && tt->did_ifconfig_setup)

         {
             struct route_ipv4 *r;
             for (r = rl->routes, len = 0; r; r = r->next, ++len)

             {

                 test_route_helper(&ret, &count, &good, &ambig, adapters, r->gateway);

             }

 
             if ((rl->flags & RG_ENABLE) && (rl->spec.flags & RTSA_REMOTE_ENDPOINT))
             {
                 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,
         len,
         (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 = MAXDWORD;
     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;

 }
 

 void

 get_default_gateway(struct route_gateway_info *rgi)

 {

     struct gc_arena gc = gc_new();

     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);
     DWORD a_index;
     const IP_ADAPTER_INFO *ai;

     CLEAR(*rgi);

     if (row)

     {

         rgi->gateway.addr = ntohl(row->dwForwardNextHop);
         if (rgi->gateway.addr)
         {
             rgi->flags |= RGI_ADDR_DEFINED;
             a_index = adapter_index_of_ip(adapters, rgi->gateway.addr, NULL, &rgi->gateway.netmask);
             if (a_index != TUN_ADAPTER_INDEX_INVALID)
             {
                 rgi->adapter_index = a_index;
                 rgi->flags |= (RGI_IFACE_DEFINED|RGI_NETMASK_DEFINED);
                 ai = get_adapter(adapters, a_index);
                 if (ai)
                 {
                     memcpy(rgi->hwaddr, ai->Address, 6);
                     rgi->flags |= RGI_HWADDR_DEFINED;
                 }
             }
         }

     }
 

     gc_free(&gc);

 }
 
 static DWORD

 windows_route_find_if_index(const struct route_ipv4 *r, const struct tuntap *tt)

 {

     struct gc_arena gc = gc_new();
     DWORD ret = TUN_ADAPTER_INDEX_INVALID;
     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 = TUN_ADAPTER_INDEX_INVALID;

     }

     else if (count > 1)

     {

         msg(M_WARN, "Warning: route gateway is ambiguous: %s (%d matches)",
             print_in_addr_t(r->gateway, 0, &gc),
             count);

     }
 

     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;

 }
 

 /* IPv6 implementation using GetBestRoute2()
  *   (TBD: dynamic linking so the binary can still run on XP?)
  * https://msdn.microsoft.com/en-us/library/windows/desktop/aa365922(v=vs.85).aspx
  * https://msdn.microsoft.com/en-us/library/windows/desktop/aa814411(v=vs.85).aspx

  */
 void
 get_default_gateway_ipv6(struct route_ipv6_gateway_info *rgi6,

                          const struct in6_addr *dest)

 {

     struct gc_arena gc = gc_new();

     MIB_IPFORWARD_ROW2 BestRoute;
     SOCKADDR_INET DestinationAddress, BestSourceAddress;
     DWORD BestIfIndex;
     DWORD status;
     NET_LUID InterfaceLuid;
 

     CLEAR(*rgi6);

     CLEAR(InterfaceLuid);               /* cleared = not used for lookup */

     CLEAR(DestinationAddress);
 
     DestinationAddress.si_family = AF_INET6;

     if (dest)

     {
         DestinationAddress.Ipv6.sin6_addr = *dest;
     }
 
     status = GetBestInterfaceEx( &DestinationAddress, &BestIfIndex );
 
     if (status != NO_ERROR)
     {

         msg(D_ROUTE, "NOTE: GetBestInterfaceEx returned error: %s (code=%u)",
             strerror_win32(status, &gc),
             (unsigned int)status);
         goto done;

     }
 
     msg( D_ROUTE, "GetBestInterfaceEx() returned if=%d", (int) BestIfIndex );
 
     status = GetBestRoute2( &InterfaceLuid, BestIfIndex, NULL,
                             &DestinationAddress, 0,
                             &BestRoute, &BestSourceAddress );
 
     if (status != NO_ERROR)
     {

         msg(D_ROUTE, "NOTE: GetIpForwardEntry2 returned error: %s (code=%u)",
             strerror_win32(status, &gc),
             (unsigned int)status);
         goto done;

     }
 

     msg( D_ROUTE, "GDG6: II=%lu DP=%s/%d NH=%s",

          BestRoute.InterfaceIndex,
          print_in6_addr( BestRoute.DestinationPrefix.Prefix.Ipv6.sin6_addr, 0, &gc),
          BestRoute.DestinationPrefix.PrefixLength,
          print_in6_addr( BestRoute.NextHop.Ipv6.sin6_addr, 0, &gc) );

     msg( D_ROUTE, "GDG6: Metric=%d, Loopback=%d, AA=%d, I=%d",

          (int) BestRoute.Metric,
          (int) BestRoute.Loopback,
          (int) BestRoute.AutoconfigureAddress,
          (int) BestRoute.Immortal );

 
     rgi6->gateway.addr_ipv6 = BestRoute.NextHop.Ipv6.sin6_addr;
     rgi6->adapter_index     = BestRoute.InterfaceIndex;
     rgi6->flags |= RGI_ADDR_DEFINED | RGI_IFACE_DEFINED;
 
     /* on-link is signalled by receiving an empty (::) NextHop */

     if (IN6_IS_ADDR_UNSPECIFIED(&BestRoute.NextHop.Ipv6.sin6_addr) )
     {
         rgi6->flags |= RGI_ON_LINK;
     }

 done:
     gc_free(&gc);

 }
 

 bool

 add_route_ipapi(const struct route_ipv4 *r, const struct tuntap *tt, DWORD adapter_index)
 {
     struct gc_arena gc = gc_new();
     bool ret = false;
     DWORD status;
     const DWORD if_index = (adapter_index == TUN_ADAPTER_INDEX_INVALID) ? windows_route_find_if_index(r, tt) : adapter_index;
 
     if (if_index != TUN_ADAPTER_INDEX_INVALID)
     {
         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->flags & RT_METRIC_DEFINED) ? r->metric : 1;
         fr.dwForwardMetric2 = METRIC_NOT_USED;
         fr.dwForwardMetric3 = METRIC_NOT_USED;
         fr.dwForwardMetric4 = METRIC_NOT_USED;
         fr.dwForwardMetric5 = METRIC_NOT_USED;
 
         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_ipv4 *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 != TUN_ADAPTER_INDEX_INVALID)

     {

         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 bool

 do_route_service(const bool add, const route_message_t *rt, const size_t size, HANDLE pipe)

 {

     DWORD len;
     bool ret = false;
     ack_message_t ack;
     struct gc_arena gc = gc_new();

     if (!WriteFile(pipe, rt, size, &len, NULL)
         || !ReadFile(pipe, &ack, sizeof(ack), &len, NULL))

     {

         msg(M_WARN, "ROUTE: could not talk to service: %s [%lu]",
             strerror_win32(GetLastError(), &gc), GetLastError());
         goto out;

     }
 

     if (ack.error_number != NO_ERROR)

     {

         msg(M_WARN, "ROUTE: route %s failed using service: %s [status=%u if_index=%d]",

             (add ? "addition" : "deletion"), strerror_win32(ack.error_number, &gc),
             ack.error_number, rt->iface.index);
         goto out;

     }
 

     ret = true;

 
 out:

     gc_free(&gc);
     return ret;

 }
 
 static bool

 do_route_ipv4_service(const bool add, const struct route_ipv4 *r, const struct tuntap *tt)

 {

     DWORD if_index = windows_route_find_if_index(r, tt);
     if (if_index == ~0)
     {
         return false;
     }

     route_message_t msg = {
         .header = {
             (add ? msg_add_route : msg_del_route),
             sizeof(route_message_t),
             0
         },
         .family = AF_INET,
         .prefix.ipv4.s_addr = htonl(r->network),
         .gateway.ipv4.s_addr = htonl(r->gateway),
         .iface = { .index = if_index, .name = "" },
         .metric = (r->flags & RT_METRIC_DEFINED ? r->metric : -1)
     };
 
     netmask_to_netbits(r->network, r->netmask, &msg.prefix_len);
     if (msg.prefix_len == -1)
     {
         msg.prefix_len = 32;
     }

     return do_route_service(add, &msg, sizeof(msg), tt->options.msg_channel);

 }
 
 static bool

 do_route_ipv6_service(const bool add, const struct route_ipv6 *r, const struct tuntap *tt)

 {

     bool status;
     route_message_t msg = {
         .header = {
             (add ? msg_add_route : msg_del_route),
             sizeof(route_message_t),
             0
         },
         .family = AF_INET6,
         .prefix.ipv6 = r->network,
         .prefix_len = r->netbits,
         .gateway.ipv6 = r->gateway,
         .iface = { .index = tt->adapter_index, .name = "" },
         .metric = ( (r->flags & RT_METRIC_DEFINED) ? r->metric : -1)
     };
 
     if (r->adapter_index)               /* vpn server special route */
     {
         msg.iface.index = r->adapter_index;
     }

     /* In TUN mode we use a special link-local address as the next hop.
      * The tapdrvr knows about it and will answer neighbor discovery packets.

      * (only do this for routes actually using the tun/tap device)

      */

     if (tt->type == DEV_TYPE_TUN
 	 && msg.iface.index == tt->adapter_index )

     {
         inet_pton(AF_INET6, "fe80::8", &msg.gateway.ipv6);
     }

     if (msg.iface.index == TUN_ADAPTER_INDEX_INVALID)

     {

         strncpy(msg.iface.name, tt->actual_name, sizeof(msg.iface.name));
         msg.iface.name[sizeof(msg.iface.name) - 1] = '\0';

     }
 

     status = do_route_service(add, &msg, sizeof(msg), tt->options.msg_channel);
     msg(D_ROUTE, "IPv6 route %s via service %s",
         add ? "addition" : "deletion",
         status ? "succeeded" : "failed");
     return status;

 }
 
 static bool

 add_route_service(const struct route_ipv4 *r, const struct tuntap *tt)

 {

     return do_route_ipv4_service(true, r, tt);

 }
 
 static bool

 del_route_service(const struct route_ipv4 *r, const struct tuntap *tt)

 {

     return do_route_ipv4_service(false, r, tt);

 }
 
 static bool

 add_route_ipv6_service(const struct route_ipv6 *r, const struct tuntap *tt)

 {

     return do_route_ipv6_service(true, r, tt);

 }
 
 static bool

 del_route_ipv6_service(const struct route_ipv6 *r, const struct tuntap *tt)

 {

     return do_route_ipv6_service(false, r, tt);

 }
 

 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) || defined(TARGET_ANDROID)

 void

 get_default_gateway(struct route_gateway_info *rgi)

 {

     struct gc_arena gc = gc_new();
     int sd = -1;
     char best_name[16];
     best_name[0] = 0;

     CLEAR(*rgi);

 #ifndef TARGET_ANDROID

     /* get default gateway IP addr */
     {
         FILE *fp = fopen("/proc/net/route", "r");
         if (fp)
         {
             char line[256];
             int count = 0;
             unsigned int lowest_metric = UINT_MAX;
             in_addr_t best_gw = 0;
             bool found = false;
             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;
                     unsigned int flags = 0;
                     char name[16];
                     name[0] = 0;
                     const int np = sscanf(line, "%15s\t%x\t%x\t%x\t%*s\t%*s\t%d\t%x",
                                           name,
                                           &net_x,
                                           &gw_x,
                                           &flags,
                                           &metric,
                                           &mask_x);
                     if (np == 6 && (flags & IFF_UP))
                     {
                         const in_addr_t net = ntohl(net_x);
                         const in_addr_t mask = ntohl(mask_x);
                         const in_addr_t gw = ntohl(gw_x);
 
                         if (!net && !mask && metric < lowest_metric)
                         {
                             found = true;
                             best_gw = gw;
                             strcpy(best_name, name);
                             lowest_metric = metric;
                         }
                     }
                 }
                 ++count;
             }
             fclose(fp);
 
             if (found)
             {
                 rgi->gateway.addr = best_gw;
                 rgi->flags |= RGI_ADDR_DEFINED;
                 if (!rgi->gateway.addr && best_name[0])
                 {
                     rgi->flags |= RGI_ON_LINK;
                 }
             }
         }
     }
 #else  /* ifndef TARGET_ANDROID */
     /* Android, set some pseudo GW, addr is in host byte order,
      * Determining the default GW on Android 5.0+ is non trivial
      * and serves almost no purpose since OpenVPN only uses the
      * default GW address to add routes for networks that should
      * NOT be routed over the VPN. Using a well known address
      * (127.'d'.'g'.'w') for the default GW make detecting
      * these routes easier from the controlling app.
      */
     rgi->gateway.addr = 127 << 24 | 'd' << 16 | 'g' << 8 | 'w';
     rgi->flags |= RGI_ADDR_DEFINED;
     strcpy(best_name, "android-gw");
 #endif /* ifndef TARGET_ANDROID */
 
     /* scan adapter list */
     if (rgi->flags & RGI_ADDR_DEFINED)
     {
         struct ifreq *ifr, *ifend;
         in_addr_t addr, netmask;
         struct ifreq ifreq;
         struct ifconf ifc;
         struct ifreq ifs[20]; /* Maximum number of interfaces to scan */

         if ((sd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
         {
             msg(M_WARN, "GDG: socket() failed");
             goto done;
         }
         ifc.ifc_len = sizeof(ifs);
         ifc.ifc_req = ifs;
         if (ioctl(sd, SIOCGIFCONF, &ifc) < 0)
         {
             msg(M_WARN, "GDG: ioctl(SIOCGIFCONF) failed");
             goto done;
         }
 
         /* 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)
             {
                 /* get interface addr */
                 addr = ntohl(((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr);
 
                 /* get interface name */
                 strncpynt(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
 
                 /* check that the interface is up */
                 if (ioctl(sd, SIOCGIFFLAGS, &ifreq) < 0)
                 {
                     continue;
                 }
                 if (!(ifreq.ifr_flags & IFF_UP))
                 {
                     continue;
                 }
 
                 if (rgi->flags & RGI_ON_LINK)
                 {
                     /* check that interface name of current interface
                      * matches interface name of best default route */
                     if (strcmp(ifreq.ifr_name, best_name))
                     {
                         continue;
                     }

 #if 0

                     /* if point-to-point link, use remote addr as route gateway */
                     if ((ifreq.ifr_flags & IFF_POINTOPOINT) && ioctl(sd, SIOCGIFDSTADDR, &ifreq) >= 0)
                     {
                         rgi->gateway.addr = ntohl(((struct sockaddr_in *) &ifreq.ifr_addr)->sin_addr.s_addr);
                         if (rgi->gateway.addr)
                         {
                             rgi->flags &= ~RGI_ON_LINK;
                         }
                     }

 #endif

                 }
                 else
                 {
                     /* get interface netmask */
                     if (ioctl(sd, SIOCGIFNETMASK, &ifreq) < 0)
                     {
                         continue;
                     }
                     netmask = ntohl(((struct sockaddr_in *) &ifreq.ifr_addr)->sin_addr.s_addr);
 
                     /* check that interface matches default route */
                     if (((rgi->gateway.addr ^ addr) & netmask) != 0)
                     {
                         continue;
                     }
 
                     /* save netmask */
                     rgi->gateway.netmask = netmask;
                     rgi->flags |= RGI_NETMASK_DEFINED;
                 }
 
                 /* save iface name */
                 strncpynt(rgi->iface, ifreq.ifr_name, sizeof(rgi->iface));
                 rgi->flags |= RGI_IFACE_DEFINED;
 
                 /* now get the hardware address. */
                 memset(&ifreq.ifr_hwaddr, 0, sizeof(struct sockaddr));
                 if (ioctl(sd, SIOCGIFHWADDR, &ifreq) < 0)
                 {
                     msg(M_WARN, "GDG: SIOCGIFHWADDR(%s) failed", ifreq.ifr_name);
                     goto done;
                 }
                 memcpy(rgi->hwaddr, &ifreq.ifr_hwaddr.sa_data, 6);
                 rgi->flags |= RGI_HWADDR_DEFINED;
 
                 break;
             }
         }
     }
 
 done:
     if (sd >= 0)
     {
         close(sd);
     }
     gc_free(&gc);

 }
 

 /* IPv6 implementation using netlink
  * http://www.linuxjournal.com/article/7356
  * netlink(3), netlink(7), rtnetlink(7)
  * http://www.virtualbox.org/svn/vbox/trunk/src/VBox/NetworkServices/NAT/rtmon_linux.c

  */

 struct rtreq {

     struct nlmsghdr nh;
     struct rtmsg rtm;
     char attrbuf[512];

 };
 

 void
 get_default_gateway_ipv6(struct route_ipv6_gateway_info *rgi6,

                          const struct in6_addr *dest)

 {

     int nls = -1;
     struct rtreq rtreq;
     struct rtattr *rta;
 
     char rtbuf[2000];
     ssize_t ssize;
 

     CLEAR(*rgi6);

 
     nls = socket( PF_NETLINK, SOCK_RAW, NETLINK_ROUTE );

     if (nls < 0)
     {
         msg(M_WARN|M_ERRNO, "GDG6: socket() failed" ); goto done;
     }

 
     /* bind() is not needed, no unsolicited msgs coming in */
 
     /* request best matching route, see netlink(7) for explanations
      */
     CLEAR(rtreq);
     rtreq.nh.nlmsg_type = RTM_GETROUTE;

     rtreq.nh.nlmsg_flags = NLM_F_REQUEST;       /* best match only */

     rtreq.rtm.rtm_family = AF_INET6;

     rtreq.rtm.rtm_src_len = 0;                  /* not source dependent */
     rtreq.rtm.rtm_dst_len = 128;                /* exact dst */

     rtreq.rtm.rtm_table = RT_TABLE_MAIN;
     rtreq.rtm.rtm_protocol = RTPROT_UNSPEC;
     rtreq.nh.nlmsg_len = NLMSG_SPACE(sizeof(rtreq.rtm));
 
     /* set RTA_DST for target IPv6 address we want */
     rta = (struct rtattr *)(((char *) &rtreq)+NLMSG_ALIGN(rtreq.nh.nlmsg_len));
     rta->rta_type = RTA_DST;
     rta->rta_len = RTA_LENGTH(16);

     rtreq.nh.nlmsg_len = NLMSG_ALIGN(rtreq.nh.nlmsg_len)
                          +RTA_LENGTH(16);

     if (dest == NULL)                   /* ::, unspecified */
     {
         memset( RTA_DATA(rta), 0, 16 ); /* :: = all-zero */
     }

     else

     {
         memcpy( RTA_DATA(rta), (void *)dest, 16 );
     }

 
     /* send and receive reply */

     if (send( nls, &rtreq, rtreq.nh.nlmsg_len, 0 ) < 0)
     {
         msg(M_WARN|M_ERRNO, "GDG6: send() failed" ); goto done;
     }

 
     ssize = recv(nls, rtbuf, sizeof(rtbuf), MSG_TRUNC);
 
     if (ssize < 0)

     {
         msg(M_WARN|M_ERRNO, "GDG6: recv() failed" ); goto done;
     }

 
     if (ssize > sizeof(rtbuf))
     {

         msg(M_WARN, "get_default_gateway_ipv6: returned message too big for buffer (%d>%d)", (int)ssize, (int)sizeof(rtbuf) );
         goto done;

     }
 
     struct nlmsghdr *nh;
 
     for (nh = (struct nlmsghdr *)rtbuf;
          NLMSG_OK(nh, ssize);
          nh = NLMSG_NEXT(nh, ssize))
     {

         struct rtmsg *rtm;
         int attrlen;
 
         if (nh->nlmsg_type == NLMSG_DONE)
         {
             break;
         }
 
         if (nh->nlmsg_type == NLMSG_ERROR)
         {
             struct nlmsgerr *ne = (struct nlmsgerr *)NLMSG_DATA(nh);

 
             /* since linux-4.11 -ENETUNREACH is returned when no route can be
              * found. Don't print any error message in this case */
             if (ne->error != -ENETUNREACH)
             {
                 msg(M_WARN, "GDG6: NLMSG_ERROR: error %s\n",
                     strerror(-ne->error));
             }

             break;
         }
 
         if (nh->nlmsg_type != RTM_NEWROUTE)
         {
             /* shouldn't happen */
             msg(M_WARN, "GDG6: unexpected msg_type %d", nh->nlmsg_type );
             continue;
         }
 
         rtm = (struct rtmsg *)NLMSG_DATA(nh);
         attrlen = RTM_PAYLOAD(nh);
 
         /* we're only looking for routes in the main table, as "we have
          * no IPv6" will lead to a lookup result in "Local" (::/0 reject)
          */
         if (rtm->rtm_family != AF_INET6
             || rtm->rtm_table != RT_TABLE_MAIN)
         {
             continue;
         }                               /* we're not interested */
 
         for (rta = RTM_RTA(rtm);
              RTA_OK(rta, attrlen);
              rta = RTA_NEXT(rta, attrlen))
         {
             if (rta->rta_type == RTA_GATEWAY)
             {
                 if (RTA_PAYLOAD(rta) != sizeof(struct in6_addr) )
                 {
                     msg(M_WARN, "GDG6: RTA_GW size mismatch"); continue;
                 }
                 rgi6->gateway.addr_ipv6 = *(struct in6_addr *) RTA_DATA(rta);
                 rgi6->flags |= RGI_ADDR_DEFINED;
             }
             else if (rta->rta_type == RTA_OIF)
             {
                 char ifname[IF_NAMESIZE+1];
                 int oif;
                 if (RTA_PAYLOAD(rta) != sizeof(oif) )
                 {
                     msg(M_WARN, "GDG6: oif size mismatch"); continue;
                 }
 
                 memcpy(&oif, RTA_DATA(rta), sizeof(oif));
                 if_indextoname(oif,ifname);
                 strncpy( rgi6->iface, ifname, sizeof(rgi6->iface)-1 );
                 rgi6->flags |= RGI_IFACE_DEFINED;
             }
         }

     }
 
     /* if we have an interface but no gateway, the destination is on-link */
     if ( ( rgi6->flags & (RGI_IFACE_DEFINED|RGI_ADDR_DEFINED) ) ==

          RGI_IFACE_DEFINED)

     {

         rgi6->flags |= (RGI_ADDR_DEFINED | RGI_ON_LINK);
         if (dest)
         {
             rgi6->gateway.addr_ipv6 = *dest;
         }

     }
 

 done:

     if (nls >= 0)

     {
         close(nls);
     }

 }
 

 #elif defined(TARGET_DARWIN) || defined(TARGET_SOLARIS)    \
     || defined(TARGET_FREEBSD) || defined(TARGET_DRAGONFLY)    \
     || defined(TARGET_OPENBSD) || defined(TARGET_NETBSD)

 
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>

 #include <net/route.h>
 #include <net/if_dl.h>

 struct rtmsg {

     struct rt_msghdr m_rtm;
     char m_space[512];

 };

 /* the route socket code is identical for all 4 supported BSDs and for
  * MacOS X (Darwin), with one crucial difference: when going from
  * 32 bit to 64 bit, the BSDs increased the structure size but kept
  * source code compatibility by keeping the use of "long", while
  * MacOS X decided to keep binary compatibility by *changing* the API
  * to use "uint32_t", thus 32 bit on all OS X variants
  *
  * We used to have a large amount of duplicate code here which really
  * differed only in this (long) vs. (uint32_t) - IMHO, worse than
  * having a combined block for all BSDs with this single #ifdef inside
  */
 
 #if defined(TARGET_DARWIN)

 #define ROUNDUP(a) \
     ((a) > 0 ? (1 + (((a) - 1) | (sizeof(uint32_t) - 1))) : sizeof(uint32_t))

 #else

 #define ROUNDUP(a) \
     ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))

 #endif

 #if defined(TARGET_SOLARIS)
 #define NEXTADDR(w, u) \

     if (rtm_addrs & (w)) { \
         l = ROUNDUP(sizeof(u)); memmove(cp, &(u), l); cp += l; \
     }

 
 #define ADVANCE(x, n) (x += ROUNDUP(sizeof(struct sockaddr_in)))

 #else  /* if defined(TARGET_SOLARIS) */

 #define NEXTADDR(w, u) \

     if (rtm_addrs & (w)) { \
         l = ROUNDUP( ((struct sockaddr *)&(u))->sa_len); memmove(cp, &(u), l); cp += l; \
     }

 
 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))

 #endif

 
 #define max(a,b) ((a) > (b) ? (a) : (b))
 
 void

 get_default_gateway(struct route_gateway_info *rgi)

 {

     struct gc_arena gc = gc_new();
     struct rtmsg m_rtmsg;
     int sockfd = -1;
     int seq, l, pid, rtm_addrs;
     unsigned int i;
     struct sockaddr so_dst, so_mask;
     char *cp = m_rtmsg.m_space;
     struct sockaddr *gate = NULL, *ifp = NULL, *sa;
     struct  rt_msghdr *rtm_aux;

 #define rtm m_rtmsg.m_rtm

     CLEAR(*rgi);

     /* setup data to send to routing socket */
     pid = getpid();
     seq = 0;
     rtm_addrs = RTA_DST | RTA_NETMASK | RTA_IFP;

     bzero(&m_rtmsg, sizeof(m_rtmsg));
     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;

 #ifdef TARGET_OPENBSD
     rtm.rtm_tableid = getrtable();
 #endif

     rtm.rtm_addrs = rtm_addrs;

     so_dst.sa_family = AF_INET;
     so_mask.sa_family = AF_INET;

 
 #ifndef TARGET_SOLARIS

     so_dst.sa_len = sizeof(struct sockaddr_in);
     so_mask.sa_len = sizeof(struct sockaddr_in);

 #endif

     NEXTADDR(RTA_DST, so_dst);
     NEXTADDR(RTA_NETMASK, so_mask);
 
     rtm.rtm_msglen = l = cp - (char *)&m_rtmsg;
 
     /* transact with routing socket */
     sockfd = socket(PF_ROUTE, SOCK_RAW, 0);

     if (sockfd < 0)

     {
         msg(M_WARN, "GDG: socket #1 failed");
         goto done;
     }
     if (write(sockfd, (char *)&m_rtmsg, l) < 0)
     {
         msg(M_WARN, "GDG: problem writing to routing socket");
         goto done;
     }

     do
     {

         l = read(sockfd, (char *)&m_rtmsg, sizeof(m_rtmsg));
     } while (l > 0 && (rtm.rtm_seq != seq || rtm.rtm_pid != pid));

     close(sockfd);
     sockfd = -1;
 

     /* extract return data from routing socket */
     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;
                 }
                 else if (i == RTA_IFP)
                 {
                     ifp = sa;
                 }
                 ADVANCE(cp, sa);
             }
         }
     }
     else
     {
         goto done;
     }
 
     /* get gateway addr and interface name */
     if (gate != NULL)
     {
         /* get default gateway addr */
         rgi->gateway.addr = ntohl(((struct sockaddr_in *)gate)->sin_addr.s_addr);
         if (rgi->gateway.addr)
         {
             rgi->flags |= RGI_ADDR_DEFINED;
         }
 
         if (ifp)
         {
             /* get interface name */
             const struct sockaddr_dl *adl = (struct sockaddr_dl *) ifp;
             if (adl->sdl_nlen && adl->sdl_nlen < sizeof(rgi->iface))
             {
                 memcpy(rgi->iface, adl->sdl_data, adl->sdl_nlen);
                 rgi->iface[adl->sdl_nlen] = '\0';
                 rgi->flags |= RGI_IFACE_DEFINED;
             }
         }
     }
 
     /* get netmask of interface that owns default gateway */
     if (rgi->flags & RGI_IFACE_DEFINED)
     {
         struct ifreq ifr;
 
         sockfd = socket(AF_INET, SOCK_DGRAM, 0);
         if (sockfd < 0)
         {
             msg(M_WARN, "GDG: socket #2 failed");
             goto done;
         }
 
         CLEAR(ifr);
         ifr.ifr_addr.sa_family = AF_INET;
         strncpynt(ifr.ifr_name, rgi->iface, IFNAMSIZ);
 
         if (ioctl(sockfd, SIOCGIFNETMASK, (char *)&ifr) < 0)
         {
             msg(M_WARN, "GDG: ioctl #1 failed");
             goto done;
         }
         close(sockfd);
         sockfd = -1;
 
         rgi->gateway.netmask = ntohl(((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr.s_addr);
         rgi->flags |= RGI_NETMASK_DEFINED;
     }
 
     /* try to read MAC addr associated with interface that owns default gateway */
     if (rgi->flags & RGI_IFACE_DEFINED)
     {
         struct ifconf ifc;
         struct ifreq *ifr;
         const int bufsize = 4096;
         char *buffer;
 
         buffer = (char *) gc_malloc(bufsize, true, &gc);
         sockfd = socket(AF_INET, SOCK_DGRAM, 0);
         if (sockfd < 0)
         {
             msg(M_WARN, "GDG: socket #3 failed");
             goto done;
         }
 
         ifc.ifc_len = bufsize;
         ifc.ifc_buf = buffer;
 
         if (ioctl(sockfd, SIOCGIFCONF, (char *)&ifc) < 0)
         {
             msg(M_WARN, "GDG: ioctl #2 failed");
             goto done;
         }
         close(sockfd);
         sockfd = -1;
 
         for (cp = buffer; cp <= buffer + ifc.ifc_len - sizeof(struct ifreq); )
         {
             ifr = (struct ifreq *)cp;

 #if defined(TARGET_SOLARIS)

             const size_t len = sizeof(ifr->ifr_name) + sizeof(ifr->ifr_addr);

 #else

             const size_t len = sizeof(ifr->ifr_name) + max(sizeof(ifr->ifr_addr), ifr->ifr_addr.sa_len);

 #endif
 

             if (!ifr->ifr_addr.sa_family)
             {
                 break;
             }
             if (!strncmp(ifr->ifr_name, rgi->iface, IFNAMSIZ))
             {
                 if (ifr->ifr_addr.sa_family == AF_LINK)
                 {
                     struct sockaddr_dl *sdl = (struct sockaddr_dl *)&ifr->ifr_addr;
                     memcpy(rgi->hwaddr, LLADDR(sdl), 6);
                     rgi->flags |= RGI_HWADDR_DEFINED;
                 }
             }
             cp += len;
         }
     }
 
 done:
     if (sockfd >= 0)
     {
         close(sockfd);
     }
     gc_free(&gc);

 }
 

 /* BSD implementation using routing socket (as does IPv4)
  * (the code duplication is somewhat unavoidable if we want this to
  * work on OpenSolaris as well.  *sigh*)

  */

 
 /* Solaris has no length field - this is ugly, but less #ifdef in total
  */
 #if defined(TARGET_SOLARIS)

 #undef ADVANCE
 #define ADVANCE(x, n) (x += ROUNDUP(sizeof(struct sockaddr_in6)))

 #endif
 

 void
 get_default_gateway_ipv6(struct route_ipv6_gateway_info *rgi6,

                          const struct in6_addr *dest)

 {

 
     struct rtmsg m_rtmsg;
     int sockfd = -1;

     int seq, l, pid, rtm_addrs;
     unsigned int i;

     struct sockaddr_in6 so_dst, so_mask;
     char *cp = m_rtmsg.m_space;
     struct sockaddr *gate = NULL, *ifp = NULL, *sa;
     struct rt_msghdr *rtm_aux;
 

     CLEAR(*rgi6);

 
     /* setup data to send to routing socket */
     pid = getpid();
     seq = 0;
     rtm_addrs = RTA_DST | RTA_NETMASK | RTA_IFP;
 
     bzero(&m_rtmsg, sizeof(m_rtmsg));
     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;
     rtm.rtm_version = RTM_VERSION;
     rtm.rtm_seq = ++seq;

 #ifdef TARGET_OPENBSD
     rtm.rtm_tableid = getrtable();
 #endif

 
     so_dst.sin6_family = AF_INET6;
     so_mask.sin6_family = AF_INET6;
 

     if (dest != NULL                    /* specific host? */
         && !IN6_IS_ADDR_UNSPECIFIED(dest) )

     {

         so_dst.sin6_addr = *dest;
         /* :: needs /0 "netmask", host route wants "no netmask */
         rtm_addrs &= ~RTA_NETMASK;

     }
 
     rtm.rtm_addrs = rtm_addrs;
 
 #ifndef TARGET_SOLARIS
     so_dst.sin6_len = sizeof(struct sockaddr_in6);
     so_mask.sin6_len = sizeof(struct sockaddr_in6);
 #endif
 
     NEXTADDR(RTA_DST, so_dst);
     NEXTADDR(RTA_NETMASK, so_mask);
 
     rtm.rtm_msglen = l = cp - (char *)&m_rtmsg;
 
     /* transact with routing socket */
     sockfd = socket(PF_ROUTE, SOCK_RAW, 0);
     if (sockfd < 0)
     {

         msg(M_WARN, "GDG6: socket #1 failed");
         goto done;

     }
     if (write(sockfd, (char *)&m_rtmsg, l) < 0)
     {

         msg(M_WARN, "GDG6: problem writing to routing socket");
         goto done;

     }
 
     do
     {

         l = read(sockfd, (char *)&m_rtmsg, sizeof(m_rtmsg));

     }
     while (l > 0 && (rtm.rtm_seq != seq || rtm.rtm_pid != pid));
 
     close(sockfd);
     sockfd = -1;
 
     /* extract return data from routing socket */
     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;
                 }
                 else if (i == RTA_IFP)
                 {
                     ifp = sa;
                 }
                 ADVANCE(cp, sa);
             }
         }

     }
     else

     {
         goto done;
     }

 
     /* get gateway addr and interface name */

     if (gate != NULL)

     {

         struct sockaddr_in6 *s6 = (struct sockaddr_in6 *)gate;
         struct in6_addr gw = s6->sin6_addr;

 
 #ifndef TARGET_SOLARIS

         /* You do not really want to know... from FreeBSD's route.c
          * (KAME encodes the 16 bit scope_id in s6_addr[2] + [3],
          * but for a correct link-local address these must be :0000: )
          */
         if (gate->sa_len == sizeof(struct sockaddr_in6)
             && IN6_IS_ADDR_LINKLOCAL(&gw) )
         {
             gw.s6_addr[2] = gw.s6_addr[3] = 0;
         }
 
         if (gate->sa_len != sizeof(struct sockaddr_in6)
             || IN6_IS_ADDR_UNSPECIFIED(&gw) )
         {
             rgi6->flags |= RGI_ON_LINK;
         }
         else

 #endif
 

         rgi6->gateway.addr_ipv6 = gw;
         rgi6->flags |= RGI_ADDR_DEFINED;

         if (ifp)
         {
             /* get interface name */
             const struct sockaddr_dl *adl = (struct sockaddr_dl *) ifp;
             if (adl->sdl_nlen && adl->sdl_nlen < sizeof(rgi6->iface))
             {
                 memcpy(rgi6->iface, adl->sdl_data, adl->sdl_nlen);
                 rgi6->flags |= RGI_IFACE_DEFINED;
             }
         }

     }
 

 done:

     if (sockfd >= 0)

     {
         close(sockfd);
     }

 }
 

 #undef max
 

 #else  /* if defined(_WIN32) */

 /*
  * This is a platform-specific method that returns data about
  * the current default gateway.  Return data is placed into
  * a struct route_gateway_info object provided by caller.  The
  * implementation should CLEAR the structure before adding
  * data to it.
  *
  * Data returned includes:
  * 1. default gateway address (rgi->gateway.addr)
  * 2. netmask of interface that owns default gateway
  *    (rgi->gateway.netmask)
  * 3. hardware address (i.e. MAC address) of interface that owns
  *    default gateway (rgi->hwaddr)
  * 4. interface name (or adapter index on Windows) that owns default
  *    gateway (rgi->iface or rgi->adapter_index)
  * 5. an array of additional address/netmask pairs defined by
  *    interface that owns default gateway (rgi->addrs with length
  *    given in rgi->n_addrs)
  *
  * The flags RGI_x_DEFINED may be used to indicate which of the data
  * members were successfully returned (set in rgi->flags).  All of
  * the data members are optional, however certain OpenVPN functionality
  * may be disabled by missing items.
  */
 void

 get_default_gateway(struct route_gateway_info *rgi)

 {

     CLEAR(*rgi);

 }

 void
 get_default_gateway_ipv6(struct route_ipv6_gateway_info *rgi6,

                          const struct in6_addr *dest)

 {
     msg(D_ROUTE, "no support for get_default_gateway_ipv6() on this system");
     CLEAR(*rgi6);
 }

 #endif /* if defined(_WIN32) */

 
 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;

 }

 /* similar to netmask_to_netbits(), but don't mess with base address
  * etc., just convert to netbits - non-mappable masks are returned as "-1"
  */

 int
 netmask_to_netbits2(in_addr_t netmask)

 {

     int i;
     const int addrlen = sizeof(in_addr_t) * 8;

     for (i = 0; i <= addrlen; ++i)

     {

         in_addr_t mask = netbits_to_netmask(i);
         if (mask == netmask)
         {
             return i;
         }

     }

     return -1;

 }
 
 

 /*
  * 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, NULL) == TLA_NONLOCAL && addr != 0 && addr != IPV4_NETMASK_HOST)
     {
         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  /* if defined(_WIN32) */

 
 static void

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

 {
 }
 

 #endif /* if defined(_WIN32) */

 /*
  * 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, const struct route_gateway_info *rgi)

 {

     struct gc_arena gc = gc_new();
     const in_addr_t nonlocal_netmask = 0x80000000L; /* routes with netmask <= to this are considered non-local */
     int 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  /* if defined(_WIN32) */

 
 int

 test_local_addr(const in_addr_t addr, const struct route_gateway_info *rgi)  /* PLATFORM-SPECIFIC */

 {

     if (rgi)

     {

         if (local_route(addr, 0xFFFFFFFF, rgi->gateway.addr, rgi))
         {
             return TLA_LOCAL;
         }
         else
         {
             return TLA_NONLOCAL;
         }

     }

     return TLA_NOT_IMPLEMENTED;

 }
 

 #endif /* if defined(_WIN32) */