diff options
Diffstat (limited to 'route.c')
| -rw-r--r-- | route.c | 253 |
1 files changed, 217 insertions, 36 deletions
@@ -46,6 +46,45 @@ static void add_route (struct route *r, const struct tuntap *tt, unsigned int flags, const struct env_set *es); static void delete_route (const struct route *r, const struct tuntap *tt, unsigned int flags, const struct env_set *es); static bool get_default_gateway (in_addr_t *ret); +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_DEBUG, "ROUTE DEBUG: 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) @@ -287,10 +326,13 @@ init_route_list (struct route_list *rl, 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; @@ -301,10 +343,16 @@ init_route_list (struct route_list *rl, if (rl->spec.net_gateway_defined) { setenv_route_addr (es, "net_gateway", rl->spec.net_gateway, -1); + dmsg (D_ROUTE_DEBUG, "ROUTE DEBUG: default_gateway=%s", print_in_addr_t (rl->spec.net_gateway, 0, &gc)); + } + + if (rl->flags & RG_ENABLE) + { + get_bypass_addresses (&rl->spec.bypass, rl->flags); +#ifdef ENABLE_DEBUG + print_bypass_addresses (&rl->spec.bypass); +#endif } - rl->redirect_default_gateway = opt->redirect_default_gateway; - rl->redirect_local = opt->redirect_local; - rl->redirect_def1 = opt->redirect_def1; if (is_route_parm_defined (remote_endpoint)) { @@ -348,6 +396,7 @@ init_route_list (struct route_list *rl, rl->n = j; } + gc_free (&gc); return ret; } @@ -386,11 +435,51 @@ del_route3 (in_addr_t network, } static void +add_bypass_routes (struct route_bypass *rb, + in_addr_t gateway, + const struct tuntap *tt, + unsigned int flags, + const struct env_set *es) +{ + int i; + for (i = 0; i < rb->n_bypass; ++i) + { + if (rb->bypass[i] != gateway) + add_route3 (rb->bypass[i], + ~0, + gateway, + tt, + flags, + es); + } +} + +static void +del_bypass_routes (struct route_bypass *rb, + in_addr_t gateway, + const struct tuntap *tt, + unsigned int flags, + const struct env_set *es) +{ + int i; + for (i = 0; i < rb->n_bypass; ++i) + { + if (rb->bypass[i] != gateway) + del_route3 (rb->bypass[i], + ~0, + gateway, + tt, + flags, + es); + } +} + +static void redirect_default_route_to_vpn (struct route_list *rl, const struct tuntap *tt, unsigned int flags, const struct env_set *es) { const char err[] = "NOTE: unable to redirect default gateway --"; - if (rl->redirect_default_gateway) + if (rl->flags & RG_ENABLE) { if (!rl->spec.remote_endpoint_defined) { @@ -407,7 +496,7 @@ redirect_default_route_to_vpn (struct route_list *rl, const struct tuntap *tt, u else { /* route remote host to original default gateway */ - if (!rl->redirect_local) + if (!(rl->flags & RG_LOCAL)) add_route3 (rl->spec.remote_host, ~0, rl->spec.net_gateway, @@ -415,7 +504,10 @@ redirect_default_route_to_vpn (struct route_list *rl, const struct tuntap *tt, u flags, es); - if (rl->redirect_def1) + /* route DHCP/DNS server traffic through original default gateway */ + add_bypass_routes (&rl->spec.bypass, rl->spec.net_gateway, tt, flags, es); + + if (rl->flags & RG_DEF1) { /* add new default route (1st component) */ add_route3 (0x00000000, @@ -464,7 +556,7 @@ undo_redirect_default_route_to_vpn (struct route_list *rl, const struct tuntap * if (rl->did_redirect_default_gateway) { /* delete remote host route */ - if (!rl->redirect_local) + if (!(rl->flags & RG_LOCAL)) del_route3 (rl->spec.remote_host, ~0, rl->spec.net_gateway, @@ -472,7 +564,10 @@ undo_redirect_default_route_to_vpn (struct route_list *rl, const struct tuntap * flags, es); - if (rl->redirect_def1) + /* delete special DHCP/DNS bypass route */ + del_bypass_routes (&rl->spec.bypass, rl->spec.net_gateway, tt, flags, es); + + if (rl->flags & RG_DEF1) { /* delete default route (1st component) */ del_route3 (0x00000000, @@ -585,9 +680,9 @@ print_route_options (const struct route_option_list *rol, int level) { int i; - if (rol->redirect_default_gateway) + if (rol->flags & RG_ENABLE) msg (level, " [redirect_default_gateway local=%d]", - rol->redirect_local); + (rol->flags & RG_LOCAL) != 0); for (i = 0; i < rol->n; ++i) print_route_option (&rol->routes[i], level); } @@ -987,7 +1082,7 @@ test_routes (const struct route_list *rl, const struct tuntap *tt) for (i = 0; i < rl->n; ++i) test_route_helper (&ret, &count, &good, &ambig, adapters, rl->routes[i].gateway); - if (rl->redirect_default_gateway && rl->spec.remote_endpoint_defined) + if ((rl->flags & RG_ENABLE) && rl->spec.remote_endpoint_defined) test_route_helper (&ret, &count, &good, &ambig, adapters, rl->spec.remote_endpoint); } } @@ -1004,40 +1099,55 @@ test_routes (const struct route_list *rl, const struct tuntap *tt) return ret; } -static bool -get_default_gateway (in_addr_t *ret) +static const MIB_IPFORWARDROW * +get_default_gateway_row (const MIB_IPFORWARDTABLE *routes) { - struct gc_arena gc = gc_new (); - bool ret_bool = false; + DWORD lowest_index = ~0; + const MIB_IPFORWARDROW *ret = NULL; int i; - const MIB_IPFORWARDTABLE *routes = get_windows_routing_table (&gc); - if (!routes) - goto done; - - for (i = 0; i < routes->dwNumEntries; ++i) + if (routes) { - const MIB_IPFORWARDROW *row = &routes->table[i]; - const in_addr_t net = ntohl (row->dwForwardDest); - const in_addr_t mask = ntohl (row->dwForwardMask); - const in_addr_t gw = ntohl (row->dwForwardNextHop); + 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; #if 0 - msg (M_INFO, "route[%d] %s %s %s", - i, - print_in_addr_t ((in_addr_t) net, 0, &gc), - print_in_addr_t ((in_addr_t) mask, 0, &gc), - print_in_addr_t ((in_addr_t) gw, 0, &gc)); + msg (M_INFO, "route[%d] %s %s %s", + i, + print_in_addr_t ((in_addr_t) net, 0, &gc), + print_in_addr_t ((in_addr_t) mask, 0, &gc), + print_in_addr_t ((in_addr_t) gw, 0, &gc)); #endif - if (!net && !mask) - { - *ret = gw; - ret_bool = true; - break; + + if (!net && !mask && index < lowest_index) + { + ret = row; + lowest_index = index; + } } } - - done: + return ret; +} + +static bool +get_default_gateway (in_addr_t *ret) +{ + struct gc_arena gc = gc_new (); + bool ret_bool = false; + + const MIB_IPFORWARDTABLE *routes = get_windows_routing_table (&gc); + const MIB_IPFORWARDROW *row = get_default_gateway_row (routes); + + if (row) + { + *ret = ntohl (row->dwForwardNextHop); + ret_bool = true; + } + gc_free (&gc); return ret_bool; } @@ -1774,3 +1884,74 @@ netmask_to_netbits (const in_addr_t network, const in_addr_t netmask, int *netbi } return false; } + +/* + * get_bypass_addresses() is used by the redirect-gateway bypass-x + * functions to build a route bypass to selected DHCP/DNS servers, + * so that outgoing packets to these servers don't end up in the tunnel. + */ + +#if defined(WIN32) + +static void +add_host_route_if_nonlocal (struct route_bypass *rb, const in_addr_t addr, const IP_ADAPTER_INFO *dgi) +{ + if (!is_ip_in_adapter_subnet (dgi, addr, NULL)) + add_bypass_address (rb, addr); +} + +static void +add_host_route_array (struct route_bypass *rb, const IP_ADAPTER_INFO *dgi, 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, dgi); + } + 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, &dgi->DhcpServer); + + /* Bypass DNS server addresses */ + if ((flags & RG_BYPASS_DNS) && pai) + add_host_route_array (rb, dgi, &pai->DnsServerList); + } + + gc_free (&gc); +} + +#else + +static void +get_bypass_addresses (struct route_bypass *rb, const unsigned int flags) +{ +} + +#endif |