func (proxy *UDPProxy) replyLoop(proxyConn *net.UDPConn, clientAddr *net.UDPAddr, clientKey *connTrackKey) {
defer func() {
proxy.connTrackLock.Lock()
delete(proxy.connTrackTable, *clientKey)
proxy.connTrackLock.Unlock()
utils.Debugf("Done proxying between udp/%v and udp/%v", clientAddr.String(), proxy.backendAddr.String())
proxyConn.Close()
}()
readBuf := make([]byte, UDPBufSize)
for {
proxyConn.SetReadDeadline(time.Now().Add(UDPConnTrackTimeout))
again:
read, err := proxyConn.Read(readBuf)
if err != nil {
if err, ok := err.(*net.OpError); ok && err.Err == syscall.ECONNREFUSED {
// This will happen if the last write failed
// (e.g: nothing is actually listening on the
// proxied port on the container), ignore it
// and continue until UDPConnTrackTimeout
// expires:
goto again
}
return
}
for i := 0; i != read; {
written, err := proxy.listener.WriteToUDP(readBuf[i:read], clientAddr)
if err != nil {
return
}
i += written
utils.Debugf("Forwarded %v/%v bytes to udp/%v", i, read, clientAddr.String())
}
}
}
// CreateBridgeIface creates a network bridge interface on the host system with the name `ifaceName`,
// and attempts to configure it with an address which doesn't conflict with any other interface on the host.
// If it can't find an address which doesn't conflict, it will return an error.
func CreateBridgeIface(ifaceName string) error {
addrs := []string{
// Here we don't follow the convention of using the 1st IP of the range for the gateway.
// This is to use the same gateway IPs as the /24 ranges, which predate the /16 ranges.
// In theory this shouldn't matter - in practice there's bound to be a few scripts relying
// on the internal addressing or other stupid things like that.
// The shouldn't, but hey, let's not break them unless we really have to.
"172.17.42.1/16", // Don't use 172.16.0.0/16, it conflicts with EC2 DNS 172.16.0.23
"10.0.42.1/16", // Don't even try using the entire /8, that's too intrusive
"10.1.42.1/16",
"10.42.42.1/16",
"172.16.42.1/24",
"172.16.43.1/24",
"172.16.44.1/24",
"10.0.42.1/24",
"10.0.43.1/24",
"192.168.42.1/24",
"192.168.43.1/24",
"192.168.44.1/24",
}
var ifaceAddr string
for _, addr := range addrs {
_, dockerNetwork, err := net.ParseCIDR(addr)
if err != nil {
return err
}
routes, err := ip("route")
if err != nil {
return err
}
if err := checkRouteOverlaps(routes, dockerNetwork); err == nil {
ifaceAddr = addr
break
} else {
utils.Debugf("%s: %s", addr, err)
}
}
if ifaceAddr == "" {
return fmt.Errorf("Could not find a free IP address range for interface '%s'. Please configure its address manually and run 'docker -b %s'", ifaceName, ifaceName)
}
utils.Debugf("Creating bridge %s with network %s", ifaceName, ifaceAddr)
if output, err := ip("link", "add", ifaceName, "type", "bridge"); err != nil {
return fmt.Errorf("Error creating bridge: %s (output: %s)", err, output)
}
if output, err := ip("addr", "add", ifaceAddr, "dev", ifaceName); err != nil {
return fmt.Errorf("Unable to add private network: %s (%s)", err, output)
}
if output, err := ip("link", "set", ifaceName, "up"); err != nil {
return fmt.Errorf("Unable to start network bridge: %s (%s)", err, output)
}
if err := iptables("-t", "nat", "-A", "POSTROUTING", "-s", ifaceAddr,
"!", "-d", ifaceAddr, "-j", "MASQUERADE"); err != nil {
return fmt.Errorf("Unable to enable network bridge NAT: %s", err)
}
return nil
}
func (proxy *TCPProxy) Run() {
quit := make(chan bool)
defer close(quit)
utils.Debugf("Starting proxy on tcp/%v for tcp/%v", proxy.frontendAddr, proxy.backendAddr)
for {
client, err := proxy.listener.Accept()
if err != nil {
utils.Debugf("Stopping proxy on tcp/%v for tcp/%v (%v)", proxy.frontendAddr, proxy.backendAddr, err.Error())
return
}
go proxy.clientLoop(client.(*net.TCPConn), quit)
}
}
func Unmount(target string) error {
_, err := os.Stat(target)
if err != nil {
return err
}
if err := exec.Command("auplink", target, "flush").Run(); err != nil {
utils.Debugf("[warning]: couldn't run auplink before unmount: %s", err)
}
if err := syscall.Unmount(target, 0); err != nil {
return err
}
// Even though we just unmounted the filesystem, AUFS will prevent deleting the mntpoint
// for some time. We'll just keep retrying until it succeeds.
for retries := 0; retries < 1000; retries++ {
err := os.Remove(target)
if err == nil {
// rm mntpoint succeeded
return nil
}
if os.IsNotExist(err) {
// mntpoint doesn't exist anymore. Success.
return nil
}
// fmt.Printf("(%v) Remove %v returned: %v\n", retries, target, err)
time.Sleep(10 * time.Millisecond)
}
return fmt.Errorf("Umount: Failed to umount %v", target)
}
func checkRouteOverlaps(routes string, dockerNetwork *net.IPNet) error {
utils.Debugf("Routes:\n\n%s", routes)
for _, line := range strings.Split(routes, "\n") {
if strings.Trim(line, "\r\n\t ") == "" || strings.Contains(line, "default") {
continue
}
_, network, err := net.ParseCIDR(strings.Split(line, " ")[0])
if err != nil {
// is this a mask-less IP address?
if ip := net.ParseIP(strings.Split(line, " ")[0]); ip == nil {
// fail only if it's neither a network nor a mask-less IP address
return fmt.Errorf("Unexpected ip route output: %s (%s)", err, line)
} else {
_, network, err = net.ParseCIDR(ip.String() + "/32")
if err != nil {
return err
}
}
}
if err == nil && network != nil {
if networkOverlaps(dockerNetwork, network) {
return fmt.Errorf("Network %s is already routed: '%s'", dockerNetwork, line)
}
}
}
return nil
}
func (b *buildFile) addContext(container *env.Container, orig, dest string) error {
origPath := path.Join(b.context, orig)
destPath := path.Join(container.RootfsPath(), dest)
// Preserve the trailing '/'
if strings.HasSuffix(dest, "/") {
destPath = destPath + "/"
}
fi, err := os.Stat(origPath)
if err != nil {
return err
}
if fi.IsDir() {
if err := utils.CopyWithTar(origPath, destPath); err != nil {
return err
}
// First try to unpack the source as an archive
} else if err := utils.UntarPath(origPath, destPath); err != nil {
utils.Debugf("Couldn't untar %s to %s: %s", origPath, destPath, err)
// If that fails, just copy it as a regular file
if err := os.MkdirAll(path.Dir(destPath), 0755); err != nil {
return err
}
if err := utils.CopyWithTar(origPath, destPath); err != nil {
return err
}
}
return nil
}
func (proxy *TCPProxy) clientLoop(client *net.TCPConn, quit chan bool) {
backend, err := net.DialTCP("tcp", nil, proxy.backendAddr)
if err != nil {
log.Printf("Can't forward traffic to backend tcp/%v: %v\n", proxy.backendAddr, err.Error())
client.Close()
return
}
event := make(chan int64)
var broker = func(to, from *net.TCPConn) {
written, err := io.Copy(to, from)
if err != nil {
err, ok := err.(*net.OpError)
// If the socket we are writing to is shutdown with
// SHUT_WR, forward it to the other end of the pipe:
if ok && err.Err == syscall.EPIPE {
from.CloseWrite()
}
}
to.CloseRead()
event <- written
}
utils.Debugf("Forwarding traffic between tcp/%v and tcp/%v", client.RemoteAddr(), backend.RemoteAddr())
go broker(client, backend)
go broker(backend, client)
var transferred int64 = 0
for i := 0; i < 2; i++ {
select {
case written := <-event:
transferred += written
case <-quit:
// Interrupt the two brokers and "join" them.
client.Close()
backend.Close()
for ; i < 2; i++ {
transferred += <-event
}
goto done
}
}
client.Close()
backend.Close()
done:
utils.Debugf("%v bytes transferred between tcp/%v and tcp/%v", transferred, client.RemoteAddr(), backend.RemoteAddr())
}
func (b *buildFile) CmdCmd(args string) error {
var cmd []string
if err := json.Unmarshal([]byte(args), &cmd); err != nil {
utils.Debugf("Error unmarshalling: %s, setting cmd to /bin/sh -c", err)
cmd = []string{"/bin/sh", "-c", args}
}
b.config.Cmd = cmd
return nil
}
func (proxy *UDPProxy) Run() {
readBuf := make([]byte, UDPBufSize)
utils.Debugf("Starting proxy on udp/%v for udp/%v", proxy.frontendAddr, proxy.backendAddr)
for {
read, from, err := proxy.listener.ReadFromUDP(readBuf)
if err != nil {
// NOTE: Apparently ReadFrom doesn't return
// ECONNREFUSED like Read do (see comment in
// UDPProxy.replyLoop)
utils.Debugf("Stopping proxy on udp/%v for udp/%v (%v)", proxy.frontendAddr, proxy.backendAddr, err.Error())
break
}
fromKey := newConnTrackKey(from)
proxy.connTrackLock.Lock()
proxyConn, hit := proxy.connTrackTable[*fromKey]
if !hit {
proxyConn, err = net.DialUDP("udp", nil, proxy.backendAddr)
if err != nil {
log.Printf("Can't proxy a datagram to udp/%s: %v\n", proxy.backendAddr.String(), err)
continue
}
proxy.connTrackTable[*fromKey] = proxyConn
go proxy.replyLoop(proxyConn, from, fromKey)
}
proxy.connTrackLock.Unlock()
for i := 0; i != read; {
written, err := proxyConn.Write(readBuf[i:read])
if err != nil {
log.Printf("Can't proxy a datagram to udp/%s: %v\n", proxy.backendAddr.String(), err)
break
}
i += written
utils.Debugf("Forwarded %v/%v bytes to udp/%v", i, read, proxy.backendAddr.String())
}
}
}
// Release: Network cleanup - release all resources
func (iface *NetworkInterface) Release() {
if iface.disabled {
return
}
for _, nat := range iface.extPorts {
utils.Debugf("Unmaping %v/%v", nat.Proto, nat.Frontend)
if err := iface.manager.portMapper.Unmap(nat.Frontend, nat.Proto); err != nil {
log.Printf("Unable to unmap port %v/%v: %v", nat.Proto, nat.Frontend, err)
}
if nat.Proto == "tcp" {
if err := iface.manager.ipAllocator.ReleaseTCPPort(nat.Frontend); err != nil {
log.Printf("Unable to release port tcp/%v: %v", nat.Frontend, err)
}
} else if err := iface.manager.ipAllocator.ReleaseUDPPort(nat.Frontend); err != nil {
log.Printf("Unable to release port udp/%v: %v", nat.Frontend, err)
}
}
iface.manager.ipAllocator.Release(iface.IPNet.IP)
}
