2 GoVPN -- simple secure free software virtual private network daemon
3 Copyright (C) 2014-2017 Sergey Matveev <stargrave@stargrave.org>
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
31 // MTUMax is maximum MTU size of Ethernet packet
32 MTUMax = 9000 + EtherSize + 1
33 // MTUDefault is default MTU size of Ethernet packet
34 MTUDefault = 1500 + EtherSize + 1
36 ENV_IFACE = "GOVPN_IFACE"
37 ENV_REMOTE = "GOVPN_REMOTE"
41 // Version holds release string set at build time
45 // ScriptCall calls external program/script.
46 // You have to specify path to it and (inteface name as a rule) something
47 // that will be the first argument when calling it. Function will return
48 // it's output and possible error.
49 func ScriptCall(path, ifaceName, remoteAddr string) ([]byte, error) {
53 if _, err := os.Stat(path); err != nil && os.IsNotExist(err) {
56 cmd := exec.Command(path)
57 cmd.Env = append(cmd.Env, ENV_IFACE+"="+ifaceName)
58 cmd.Env = append(cmd.Env, ENV_REMOTE+"="+remoteAddr)
59 out, err := cmd.CombinedOutput()
61 log.Println("Script error", path, err, string(out))
67 func SliceZero(data []byte) {
68 for i := 0; i < len(data); i++ {
73 func VersionGet() string {
74 return "GoVPN version " + Version + " built with " + runtime.Version()