Merge pull request #709 from micro/tunnel-arp

Tunnel Direction Fix
This commit is contained in:
Asim Aslam 2019-08-29 13:13:25 +01:00 committed by GitHub
commit 6e3d53e1ee
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4 changed files with 126 additions and 42 deletions

View File

@ -49,8 +49,20 @@ type tun struct {
type link struct {
transport.Socket
id string
loopback bool
// unique id of this link e.g uuid
// which we define for ourselves
id string
// whether its a loopback connection
// this flag is used by the transport listener
// which accepts inbound quic connections
loopback bool
// whether its actually connected
// dialled side sets it to connected
// after sending the message. the
// listener waits for the connect
connected bool
// the last time we received a keepalive
// on this link from the remote side
lastKeepAlive time.Time
}
@ -173,7 +185,7 @@ func (t *tun) process() {
}
// set message head
newMsg.Header["Micro-Tunnel"] = "message"
newMsg.Header["Micro-Tunnel"] = msg.typ
// set the tunnel id on the outgoing message
newMsg.Header["Micro-Tunnel-Id"] = msg.id
@ -186,13 +198,39 @@ func (t *tun) process() {
// send the message via the interface
t.Lock()
if len(t.links) == 0 {
log.Debugf("No links to send to")
}
for node, link := range t.links {
// if the link is not connected skip it
if !link.connected {
log.Debugf("Link for node %s not connected", node)
continue
}
// if we're picking the link check the id
// this is where we explicitly set the link
// in a message received via the listen method
if len(msg.link) > 0 && link.id != msg.link {
continue
}
// if the link was a loopback accepted connection
// and the message is being sent outbound via
// a dialled connection don't use this link
if link.loopback && msg.outbound {
continue
}
// if the message was being returned by the loopback listener
// send it back up the loopback link only
if msg.loopback && !link.loopback {
continue
}
// send the message via the current link
log.Debugf("Sending %+v to %s", newMsg, node)
if err := link.Send(newMsg); err != nil {
log.Debugf("Tunnel error sending %+v to %s: %v", newMsg, node, err)
@ -200,6 +238,7 @@ func (t *tun) process() {
continue
}
}
t.Unlock()
case <-t.closed:
return
@ -209,15 +248,22 @@ func (t *tun) process() {
// process incoming messages
func (t *tun) listen(link *link) {
// remove the link on exit
defer func() {
log.Debugf("Tunnel deleting connection from %s", link.Remote())
t.Lock()
delete(t.links, link.Remote())
t.Unlock()
}()
// let us know if its a loopback
var loopback bool
for {
// process anything via the net interface
msg := new(transport.Message)
err := link.Recv(msg)
if err != nil {
if err := link.Recv(msg); err != nil {
log.Debugf("Tunnel link %s receive error: %#v", link.Remote(), err)
t.Lock()
delete(t.links, link.Remote())
t.Unlock()
return
}
@ -232,21 +278,29 @@ func (t *tun) listen(link *link) {
// are we connecting to ourselves?
if token == t.token {
t.Lock()
link.loopback = true
t.Unlock()
loopback = true
}
// set as connected
link.connected = true
// save the link once connected
t.Lock()
t.links[link.Remote()] = link
t.Unlock()
// nothing more to do
continue
case "close":
log.Debugf("Tunnel link %s closing connection", link.Remote())
// TODO: handle the close message
// maybe report io.EOF or kill the link
continue
return
case "keepalive":
log.Debugf("Tunnel link %s received keepalive", link.Remote())
t.Lock()
// save the keepalive
link.lastKeepAlive = time.Now()
t.Unlock()
continue
@ -258,6 +312,12 @@ func (t *tun) listen(link *link) {
continue
}
// if its not connected throw away the link
if !link.connected {
log.Debugf("Tunnel link %s not connected", link.id)
return
}
// strip message header
delete(msg.Header, "Micro-Tunnel")
@ -283,8 +343,10 @@ func (t *tun) listen(link *link) {
var s *socket
var exists bool
// If its a loopback connection then we've enabled link direction
// listening side is used for listening, the dialling side for dialling
switch {
case link.loopback:
case loopback:
s, exists = t.getSocket(id, "listener")
default:
// get the socket based on the tunnel id and session
@ -298,6 +360,7 @@ func (t *tun) listen(link *link) {
s, exists = t.getSocket(id, "listener")
}
}
// bail if no socket has been found
if !exists {
log.Debugf("Tunnel skipping no socket exists")
@ -337,9 +400,11 @@ func (t *tun) listen(link *link) {
// construct the internal message
imsg := &message{
id: id,
session: session,
data: tmsg,
id: id,
session: session,
data: tmsg,
link: link.id,
loopback: loopback,
}
// append to recv backlog
@ -399,13 +464,11 @@ func (t *tun) setupLink(node string) (*link, error) {
return nil, err
}
// save the link
id := uuid.New().String()
link := &link{
Socket: c,
id: id,
}
t.links[node] = link
// create a new link
link := newLink(c)
link.connected = true
// we made the outbound connection
// and sent the connect message
// process incoming messages
go t.listen(link)
@ -430,30 +493,18 @@ func (t *tun) connect() error {
// accept inbound connections
err := l.Accept(func(sock transport.Socket) {
log.Debugf("Tunnel accepted connection from %s", sock.Remote())
// save the link
id := uuid.New().String()
t.Lock()
link := &link{
Socket: sock,
id: id,
}
t.links[sock.Remote()] = link
t.Unlock()
// delete the link
defer func() {
log.Debugf("Tunnel deleting connection from %s", sock.Remote())
t.Lock()
delete(t.links, sock.Remote())
t.Unlock()
}()
// create a new link
link := newLink(sock)
// listen for inbound messages
// listen for inbound messages.
// only save the link once connected.
// we do this inside liste
t.listen(link)
})
t.Lock()
defer t.Unlock()
t.RLock()
defer t.RUnlock()
// still connected but the tunnel died
if err != nil && t.connected {
@ -473,6 +524,7 @@ func (t *tun) connect() error {
log.Debugf("Tunnel failed to establish node link to %s: %v", node, err)
continue
}
// save the link
t.links[node] = link
}

13
tunnel/link.go Normal file
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@ -0,0 +1,13 @@
package tunnel
import (
"github.com/google/uuid"
"github.com/micro/go-micro/transport"
)
func newLink(s transport.Socket) *link {
return &link{
Socket: s,
id: uuid.New().String(),
}
}

View File

@ -41,6 +41,10 @@ func (t *tunListener) process() {
id: m.id,
// the session id
session: m.session,
// is loopback conn
loopback: m.loopback,
// the link the message was received on
link: m.link,
// close chan
closed: make(chan bool),
// recv called by the acceptor

View File

@ -25,18 +25,28 @@ type socket struct {
recv chan *message
// wait until we have a connection
wait chan bool
// outbound marks the socket as outbound
// outbound marks the socket as outbound dialled connection
outbound bool
// lookback marks the socket as a loopback on the inbound
loopback bool
// the link on which this message was received
link string
}
// message is sent over the send channel
type message struct {
// type of message
typ string
// tunnel id
id string
// the session id
session string
// outbound marks the message as outbound
outbound bool
// loopback marks the message intended for loopback
loopback bool
// the link to send the message on
link string
// transport data
data *transport.Message
}
@ -77,10 +87,15 @@ func (s *socket) Send(m *transport.Message) error {
// append to backlog
msg := &message{
typ: "message",
id: s.id,
session: s.session,
outbound: s.outbound,
loopback: s.loopback,
data: data,
// specify the link on which to send this
// it will be blank for dialled sockets
link: s.link,
}
log.Debugf("Appending %+v to send backlog", msg)
s.send <- msg