Fix: Use netsh for adding routes on Windows (wintun)

- Get wintun interface index directly after adapter creation
- Use netsh instead of CreateIpForwardEntry (doesn't work with wintun)
- Fallback to CreateIpForwardEntry if netsh fails

src/tun_if.h

@@ -56,6 +56,7 @@ struct tun_if {
     HANDLE           read_thread;
     HANDLE           stop_event;
     volatile int     running;             // 1 = поток работает
+    DWORD            ifindex;              // Windows: интерфейсный индекс
 #endif
 };
 

src/tun_route.c

@@ -138,10 +138,9 @@ static int ip_route_cmd(const char *ifname, uint32_t network, uint8_t prefix_len
     return (ret == 0) ? 0 : -1;
 }
 
-int tun_route_add(const char *ifname, uint32_t network, uint8_t prefix_len) {
-    int ifindex = if_nametoindex(ifname);
+int tun_route_add(uint32_t ifindex, uint32_t network, uint8_t prefix_len) {
     if (ifindex == 0) {
-        DEBUG_ERROR(DEBUG_CATEGORY_TUN, "Interface %s not found", ifname);
+        DEBUG_ERROR(DEBUG_CATEGORY_TUN, "Interface index is 0");
         return -1;
     }
 
@@ -153,7 +152,9 @@ int tun_route_add(const char *ifname, uint32_t network, uint8_t prefix_len) {
     }
 
     // Fallback to ip route command
-    DEBUG_WARN(DEBUG_CATEGORY_TUN, "Netlink failed, trying ip route command for %s", ifname);
+    DEBUG_WARN(DEBUG_CATEGORY_TUN, "Netlink failed, trying ip route command for ifindex %u", ifindex);
+    char ifname[16];
+    snprintf(ifname, sizeof(ifname), "%u", ifindex);
     return ip_route_cmd(ifname, ntohl(network), prefix_len, "add");
 }
 
@@ -198,16 +199,36 @@ int tun_route_flush(const char *ifname) {
 
 // Windows IP Helper API implementation
 
-int tun_route_add(const char *ifname, uint32_t network, uint8_t prefix_len) {
+int tun_route_add(uint32_t ifindex, uint32_t network, uint8_t prefix_len) {
+    if (ifindex == 0) {
+        DEBUG_ERROR(DEBUG_CATEGORY_TUN, "tun_route_add: ifindex is 0");
+        return -1;
+    }
+    
+    uint32_t dest = htonl(network);
+    uint32_t mask = prefix_to_netmask(prefix_len);
+    
+    char cmd[256];
+    struct in_addr dest_addr;
+    dest_addr.s_addr = dest;
+    snprintf(cmd, sizeof(cmd), "netsh interface ip add route %s/%d interface=%lu store=active",
+             inet_ntoa(dest_addr), prefix_len, (unsigned long)ifindex);
+    int sys_ret = system(cmd);
+    if (sys_ret == 0) {
+        DEBUG_INFO(DEBUG_CATEGORY_TUN, "Added route %s/%d via ifindex=%lu", 
+                   inet_ntoa(dest_addr), prefix_len, (unsigned long)ifindex);
+        return 0;
+    }
+    
     MIB_IPFORWARDROW route;
     memset(&route, 0, sizeof(route));
     
-    route.dwForwardDest = htonl(network);
-    route.dwForwardMask = prefix_to_netmask(prefix_len);
+    route.dwForwardDest = dest;
+    route.dwForwardMask = mask;
     route.dwForwardPolicy = 0;
-    route.dwForwardNextHop = 0;  // On-link route
-    route.dwForwardIfIndex = if_nametoindex(ifname);
-    route.dwForwardType = MIB_IPROUTE_TYPE_DIRECT;
+    route.dwForwardNextHop = 0;
+    route.dwForwardIfIndex = ifindex;
+    route.dwForwardType = MIB_IPROUTE_TYPE_INDIRECT;
     route.dwForwardProto = MIB_IPPROTO_NETMGMT;
     route.dwForwardAge = 0;
     route.dwForwardNextHopAS = 0;
@@ -219,7 +240,8 @@ int tun_route_add(const char *ifname, uint32_t network, uint8_t prefix_len) {
     
     DWORD ret = CreateIpForwardEntry(&route);
     if (ret != NO_ERROR) {
-        DEBUG_ERROR(DEBUG_CATEGORY_TUN, "Failed to add route: %lu", ret);
+        DEBUG_ERROR(DEBUG_CATEGORY_TUN, "Failed to add route %s/%d: %lu", 
+                   inet_ntoa(dest_addr), prefix_len, ret);
         return -1;
     }
     return 0;
@@ -356,10 +378,9 @@ static int route_cmd(const char *ifname, uint32_t network, uint8_t prefix_len, c
     return (ret == 0) ? 0 : -1;
 }
 
-int tun_route_add(const char *ifname, uint32_t network, uint8_t prefix_len) {
-    int ifindex = if_nametoindex(ifname);
+int tun_route_add(uint32_t ifindex, uint32_t network, uint8_t prefix_len) {
     if (ifindex == 0) {
-        DEBUG_ERROR(DEBUG_CATEGORY_TUN, "Interface %s not found", ifname);
+        DEBUG_ERROR(DEBUG_CATEGORY_TUN, "Interface index is 0");
         return -1;
     }
 
@@ -369,7 +390,9 @@ int tun_route_add(const char *ifname, uint32_t network, uint8_t prefix_len) {
     }
 
     // Fallback to route command
-    DEBUG_WARN(DEBUG_CATEGORY_TUN, "Routing socket failed, trying route command for %s", ifname);
+    DEBUG_WARN(DEBUG_CATEGORY_TUN, "Routing socket failed, trying route command for ifindex %u", ifindex);
+    char ifname[16];
+    snprintf(ifname, sizeof(ifname), "%u", ifindex);
     return route_cmd(ifname, network, prefix_len, "add");
 }
 
@@ -406,14 +429,14 @@ int tun_route_flush(const char *ifname) {
 
 // Platform-independent functions
 
-int tun_route_add_all(const char *ifname, struct CFG_ROUTE_ENTRY *routes) {
+int tun_route_add_all(uint32_t ifindex, const char *ifname, struct CFG_ROUTE_ENTRY *routes) {
     int count = 0;
     struct CFG_ROUTE_ENTRY *entry = routes;
     
     while (entry) {
         uint32_t network = ntohl(entry->ip.addr.v4.s_addr);
         if (entry->ip.family == AF_INET) {
-            if (tun_route_add(ifname, network, entry->netmask) == 0) {
+            if (tun_route_add(ifindex, network, entry->netmask) == 0) {
                 struct in_addr addr;
                 addr.s_addr = entry->ip.addr.v4.s_addr;
                 DEBUG_INFO(DEBUG_CATEGORY_TUN, "Added route %s/%d via %s", ip_to_str(&addr, AF_INET).str, entry->netmask, ifname);

src/tun_route.h

@@ -13,12 +13,12 @@ struct CFG_ROUTE_ENTRY;
 
 /**
  * @brief Add system route for a subnet via TUN interface
- * @param ifname Interface name (e.g., "tun0")
+ * @param ifindex Interface index
  * @param network Network address in host byte order
  * @param prefix_len Prefix length (1-32)
  * @return 0 on success, -1 on error
  */
-int tun_route_add(const char *ifname, uint32_t network, uint8_t prefix_len);
+int tun_route_add(uint32_t ifindex, uint32_t network, uint8_t prefix_len);
 
 /**
  * @brief Delete system route for a subnet via TUN interface
@@ -38,11 +38,12 @@ int tun_route_flush(const char *ifname);
 
 /**
  * @brief Add multiple routes from config entries
- * @param ifname Interface name (e.g., "tun0")
+ * @param ifindex Interface index
+ * @param ifname Interface name (e.g., "tun0") - for logging only
  * @param routes Linked list of route entries
  * @return Number of routes added successfully
  */
-int tun_route_add_all(const char *ifname, struct CFG_ROUTE_ENTRY *routes);
+int tun_route_add_all(uint32_t ifindex, const char *ifname, struct CFG_ROUTE_ENTRY *routes);
 
 #ifdef __cplusplus
 }

src/tun_windows.c

@@ -172,6 +172,18 @@ int tun_platform_init(struct tun_if* tun, const char* ifname, const char* ip_str
     tun->platform_handle = session;
     tun->adapter_handle  = adapter;
     strncpy(tun->ifname, ifname && ifname[0] ? ifname : "utun", sizeof(tun->ifname)-1);
+
+    NET_LUID luid;
+    WintunGetAdapterLUID(adapter, &luid);
+    NET_IFINDEX idx = 0;
+    if (ConvertInterfaceLuidToIndex(&luid, &idx) == NO_ERROR) {
+        tun->ifindex = idx;
+        DEBUG_INFO(DEBUG_CATEGORY_TUN, "Wintun interface index: %lu", (unsigned long)idx);
+    } else {
+        tun->ifindex = 0;
+        DEBUG_ERROR(DEBUG_CATEGORY_TUN, "Failed to get interface index from LUID");
+    }
+
     return 0;
 }
 

src/utun_instance.c

@@ -106,7 +106,7 @@ static int instance_init_common(struct UTUN_INSTANCE* instance, struct UASYNC* u
         
         // Add system routes for route_subnets
         if (config->route_subnets) {
-            int added = tun_route_add_all(instance->tun->ifname, config->route_subnets);
+            int added = tun_route_add_all(instance->tun->ifindex, instance->tun->ifname, config->route_subnets);
             DEBUG_INFO(DEBUG_CATEGORY_TUN, "Added %d system routes for TUN interface", added);
         }
     } else {