tun_freebsd: reuse existing TUN interface on SIOCIFCREATE EEXIST

src/tun_freebsd.c

@@ -77,9 +77,13 @@ static int create_tun_device(char *ifname, size_t ifname_len) {
         strncpy(ifr.ifr_name, ifname, IFNAMSIZ - 1);
         ifr.ifr_name[IFNAMSIZ - 1] = '\0';
         if (ioctl(sock, SIOCIFCREATE, &ifr) < 0) {
-            DEBUG_ERROR(DEBUG_CATEGORY_TUN, "SIOCIFCREATE failed for %s: %s", ifname, strerror(errno));
-            close(sock);
-            return -1;
+            if (errno == EEXIST) {
+                DEBUG_INFO(DEBUG_CATEGORY_TUN, "TUN interface %s already exists, reusing it", ifname);
+            } else {
+                DEBUG_ERROR(DEBUG_CATEGORY_TUN, "SIOCIFCREATE failed for %s: %s", ifname, strerror(errno));
+                close(sock);
+                return -1;
+            }
         }
         close(sock);