Configure MTU on per-user basis

[govpn.git] / src / govpn / tap.go

diff --git a/src/govpn/tap.go b/src/govpn/tap.go
index 9c999b41374b2750fa05490331219b388fb88107..6e545b4decfeae9262a73f82e00348e60c89c609 100644 (file)
--- a/src/govpn/tap.go
+++ b/src/govpn/tap.go
@@ -1,6 +1,6 @@
 /*
 GoVPN -- simple secure free software virtual private network daemon
-Copyright (C) 2014-2015 Sergey Matveev <stargrave@stargrave.org>
+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
@@ -20,12 +20,6 @@ package govpn
 
 import (
        "io"
-
-       "golang.org/x/crypto/poly1305"
-)
-
-const (
-       EtherSize = 14
 )
 
 type TAP struct {
@@ -41,14 +35,7 @@ var (
        taps = make(map[string]*TAP)
 )
 
-// Return maximal acceptable TAP interface MTU. This is daemon's MTU
-// minus nonce, MAC, packet size mark and Ethernet header sizes.
-func TAPMaxMTU() int {
-       return MTU - poly1305.TagSize - NonceSize - PktSizeSize - EtherSize
-}
-
-func NewTAP(ifaceName string) (*TAP, error) {
-       maxIfacePktSize := TAPMaxMTU() + EtherSize
+func NewTAP(ifaceName string, mtu int) (*TAP, error) {
        tapRaw, err := newTAPer(ifaceName)
        if err != nil {
                return nil, err
@@ -56,8 +43,8 @@ func NewTAP(ifaceName string) (*TAP, error) {
        tap := TAP{
                Name: ifaceName,
                dev:  tapRaw,
-               buf0: make([]byte, maxIfacePktSize),
-               buf1: make([]byte, maxIfacePktSize),
+               buf0: make([]byte, mtu),
+               buf1: make([]byte, mtu),
                Sink: make(chan []byte),
        }
        go func() {
@@ -85,12 +72,12 @@ func (t *TAP) Write(data []byte) (n int, err error) {
        return t.dev.Write(data)
 }
 
-func TAPListen(ifaceName string) (*TAP, error) {
+func TAPListen(ifaceName string, mtu int) (*TAP, error) {
        tap, exists := taps[ifaceName]
        if exists {
                return tap, nil
        }
-       tap, err := NewTAP(ifaceName)
+       tap, err := NewTAP(ifaceName, mtu)
        if err != nil {
                return nil, err
        }