--- /dev/null
+/*
+GoVPN -- simple secure free software virtual private network daemon
+Copyright (C) 2014-2016 Sergey Matveev <stargrave@stargrave.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+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, see <http://www.gnu.org/licenses/>.
+*/
+
+package main
+
+import (
+ "bytes"
+
+ "github.com/pkg/errors"
+
+ "cypherpunks.ru/govpn"
+)
+
+func preUpAction(path string) govpn.TunnelPreUpAction {
+ if len(path) == 0 {
+ return nil
+ }
+
+ return func(ctx govpn.PeerContext) (*govpn.TAP, error) {
+ result, err := govpn.ScriptCall(path, ctx.Config.Iface, ctx.RemoteAddress)
+ if err != nil {
+ return nil, errors.Wrap(err, "govpn.ScriptCall")
+ }
+ if len(ctx.Config.Iface) == 0 {
+ sepIndex := bytes.Index(result, []byte{'\n'})
+ if sepIndex < 0 {
+ sepIndex = len(result)
+ }
+ ctx.Config.Iface = string(result[:sepIndex])
+ }
+
+ if len(ctx.Config.Iface) == 0 {
+ return nil, errors.Errorf("Script %q didn't returned an interface name", path)
+ }
+
+ tap, err := govpn.TAPListen(ctx.Config.Iface, ctx.Config.MTU)
+ if err != nil {
+ return nil, errors.Wrap(err, "govpn.TAPListen")
+ }
+ return tap, nil
+ }
+}