Improve TAP

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

diff --git a/src/cypherpunks.ru/govpn/tap.go b/src/cypherpunks.ru/govpn/tap.go
index f24630a1e59067acacbd305b711f77f19f677ea4..6485501479aaf4b4c12d8912d11ffdc86ca3ce96 100644 (file)
--- a/src/cypherpunks.ru/govpn/tap.go
+++ b/src/cypherpunks.ru/govpn/tap.go
@@ -1,6 +1,6 @@
 /*
 GoVPN -- simple secure free software virtual private network daemon
-Copyright (C) 2014-2017 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
@@ -20,24 +20,34 @@ package govpn
 
 import (
        "io"
+
+       "github.com/Sirupsen/logrus"
+       "github.com/pkg/errors"
+)
+
+const (
+       interfaceTap = "tap"
+       interfaceTun = "tun"
 )
 
 // TAP is a TUN or a TAP interface.
+// TODO: rename to something more... generic?
 type TAP struct {
        Name string
        Sink chan []byte
-       dev  io.ReadWriter
+       dev  io.ReadWriteCloser
 }
 
 var (
-       taps = make(map[string]*TAP)
+       taps                    = make(map[string]*TAP)
+       errUnsupportedInterface = errors.New("Unsupported interface")
 )
 
 // NewTAP creates a new TUN/TAP virtual interface
 func NewTAP(ifaceName string, mtu int) (*TAP, error) {
-       tapRaw, err := newTAPer(ifaceName)
+       tapRaw, err := newTAPer(&ifaceName)
        if err != nil {
-               return nil, err
+               return nil, errors.Wrap(err, "newTAPer")
        }
        tap := TAP{
                Name: ifaceName,
@@ -60,7 +70,15 @@ func NewTAP(ifaceName string, mtu int) (*TAP, error) {
                        bufZ = !bufZ
                        n, err = tap.dev.Read(buf)
                        if err != nil {
-                               panic("Reading TUN/TAP:" + err.Error())
+                               logger.WithError(err).WithFields(logrus.Fields{
+                                       "func": logFuncPrefix + "TAP read sink loop",
+                                       "name": tap.Name,
+                                       "mtu":  mtu,
+                               }).Error("Can't read interface")
+                               return
+                               // TODO: need a way to warn consumer that something is wrong
+                               // TODO: to force peer to just disconnect
+                               // TODO: use the client/server error channel?
                        }
                        tap.Sink <- buf[:n]
                }
@@ -68,8 +86,15 @@ func NewTAP(ifaceName string, mtu int) (*TAP, error) {
        return &tap, nil
 }
 
-func (t *TAP) Write(data []byte) (n int, err error) {
-       return t.dev.Write(data)
+func (t *TAP) Write(data []byte) (int, error) {
+       n, err := t.dev.Write(data)
+       return n, errors.Wrapf(err, "t.dev.Write %d", len(data))
+}
+
+// Close close TAP/TUN virtual network interface
+func (t *TAP) Close() error {
+       // TODO add chan to stop read loop
+       return t.dev.Close()
 }
 
 // TAPListen opens an existing TAP (creates if none exists)
@@ -80,7 +105,7 @@ func TAPListen(ifaceName string, mtu int) (*TAP, error) {
        }
        tap, err := NewTAP(ifaceName, mtu)
        if err != nil {
-               return nil, err
+               return nil, errors.Wrap(err, "NewTAP")
        }
        taps[ifaceName] = tap
        return tap, nil