mirror of
https://github.com/ceph/ceph-csi.git
synced 2024-11-27 00:30:18 +00:00
303 lines
9.4 KiB
Go
303 lines
9.4 KiB
Go
/*
|
|
Copyright 2015 The Kubernetes Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
package userspace
|
|
|
|
import (
|
|
"fmt"
|
|
"io"
|
|
"net"
|
|
"strconv"
|
|
"strings"
|
|
"sync"
|
|
"time"
|
|
|
|
"github.com/golang/glog"
|
|
"k8s.io/apimachinery/pkg/util/runtime"
|
|
api "k8s.io/kubernetes/pkg/apis/core"
|
|
"k8s.io/kubernetes/pkg/proxy"
|
|
)
|
|
|
|
// Abstraction over TCP/UDP sockets which are proxied.
|
|
type ProxySocket interface {
|
|
// Addr gets the net.Addr for a ProxySocket.
|
|
Addr() net.Addr
|
|
// Close stops the ProxySocket from accepting incoming connections.
|
|
// Each implementation should comment on the impact of calling Close
|
|
// while sessions are active.
|
|
Close() error
|
|
// ProxyLoop proxies incoming connections for the specified service to the service endpoints.
|
|
ProxyLoop(service proxy.ServicePortName, info *ServiceInfo, loadBalancer LoadBalancer)
|
|
// ListenPort returns the host port that the ProxySocket is listening on
|
|
ListenPort() int
|
|
}
|
|
|
|
func newProxySocket(protocol api.Protocol, ip net.IP, port int) (ProxySocket, error) {
|
|
host := ""
|
|
if ip != nil {
|
|
host = ip.String()
|
|
}
|
|
|
|
switch strings.ToUpper(string(protocol)) {
|
|
case "TCP":
|
|
listener, err := net.Listen("tcp", net.JoinHostPort(host, strconv.Itoa(port)))
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &tcpProxySocket{Listener: listener, port: port}, nil
|
|
case "UDP":
|
|
addr, err := net.ResolveUDPAddr("udp", net.JoinHostPort(host, strconv.Itoa(port)))
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
conn, err := net.ListenUDP("udp", addr)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &udpProxySocket{UDPConn: conn, port: port}, nil
|
|
}
|
|
return nil, fmt.Errorf("unknown protocol %q", protocol)
|
|
}
|
|
|
|
// How long we wait for a connection to a backend in seconds
|
|
var EndpointDialTimeouts = []time.Duration{250 * time.Millisecond, 500 * time.Millisecond, 1 * time.Second, 2 * time.Second}
|
|
|
|
// tcpProxySocket implements ProxySocket. Close() is implemented by net.Listener. When Close() is called,
|
|
// no new connections are allowed but existing connections are left untouched.
|
|
type tcpProxySocket struct {
|
|
net.Listener
|
|
port int
|
|
}
|
|
|
|
func (tcp *tcpProxySocket) ListenPort() int {
|
|
return tcp.port
|
|
}
|
|
|
|
// TryConnectEndpoints attempts to connect to the next available endpoint for the given service, cycling
|
|
// through until it is able to successfully connect, or it has tried with all timeouts in EndpointDialTimeouts.
|
|
func TryConnectEndpoints(service proxy.ServicePortName, srcAddr net.Addr, protocol string, loadBalancer LoadBalancer) (out net.Conn, err error) {
|
|
sessionAffinityReset := false
|
|
for _, dialTimeout := range EndpointDialTimeouts {
|
|
endpoint, err := loadBalancer.NextEndpoint(service, srcAddr, sessionAffinityReset)
|
|
if err != nil {
|
|
glog.Errorf("Couldn't find an endpoint for %s: %v", service, err)
|
|
return nil, err
|
|
}
|
|
glog.V(3).Infof("Mapped service %q to endpoint %s", service, endpoint)
|
|
// TODO: This could spin up a new goroutine to make the outbound connection,
|
|
// and keep accepting inbound traffic.
|
|
outConn, err := net.DialTimeout(protocol, endpoint, dialTimeout)
|
|
if err != nil {
|
|
if isTooManyFDsError(err) {
|
|
panic("Dial failed: " + err.Error())
|
|
}
|
|
glog.Errorf("Dial failed: %v", err)
|
|
sessionAffinityReset = true
|
|
continue
|
|
}
|
|
return outConn, nil
|
|
}
|
|
return nil, fmt.Errorf("failed to connect to an endpoint.")
|
|
}
|
|
|
|
func (tcp *tcpProxySocket) ProxyLoop(service proxy.ServicePortName, myInfo *ServiceInfo, loadBalancer LoadBalancer) {
|
|
for {
|
|
if !myInfo.IsAlive() {
|
|
// The service port was closed or replaced.
|
|
return
|
|
}
|
|
// Block until a connection is made.
|
|
inConn, err := tcp.Accept()
|
|
if err != nil {
|
|
if isTooManyFDsError(err) {
|
|
panic("Accept failed: " + err.Error())
|
|
}
|
|
|
|
if isClosedError(err) {
|
|
return
|
|
}
|
|
if !myInfo.IsAlive() {
|
|
// Then the service port was just closed so the accept failure is to be expected.
|
|
return
|
|
}
|
|
glog.Errorf("Accept failed: %v", err)
|
|
continue
|
|
}
|
|
glog.V(3).Infof("Accepted TCP connection from %v to %v", inConn.RemoteAddr(), inConn.LocalAddr())
|
|
outConn, err := TryConnectEndpoints(service, inConn.(*net.TCPConn).RemoteAddr(), "tcp", loadBalancer)
|
|
if err != nil {
|
|
glog.Errorf("Failed to connect to balancer: %v", err)
|
|
inConn.Close()
|
|
continue
|
|
}
|
|
// Spin up an async copy loop.
|
|
go ProxyTCP(inConn.(*net.TCPConn), outConn.(*net.TCPConn))
|
|
}
|
|
}
|
|
|
|
// ProxyTCP proxies data bi-directionally between in and out.
|
|
func ProxyTCP(in, out *net.TCPConn) {
|
|
var wg sync.WaitGroup
|
|
wg.Add(2)
|
|
glog.V(4).Infof("Creating proxy between %v <-> %v <-> %v <-> %v",
|
|
in.RemoteAddr(), in.LocalAddr(), out.LocalAddr(), out.RemoteAddr())
|
|
go copyBytes("from backend", in, out, &wg)
|
|
go copyBytes("to backend", out, in, &wg)
|
|
wg.Wait()
|
|
}
|
|
|
|
func copyBytes(direction string, dest, src *net.TCPConn, wg *sync.WaitGroup) {
|
|
defer wg.Done()
|
|
glog.V(4).Infof("Copying %s: %s -> %s", direction, src.RemoteAddr(), dest.RemoteAddr())
|
|
n, err := io.Copy(dest, src)
|
|
if err != nil {
|
|
if !isClosedError(err) {
|
|
glog.Errorf("I/O error: %v", err)
|
|
}
|
|
}
|
|
glog.V(4).Infof("Copied %d bytes %s: %s -> %s", n, direction, src.RemoteAddr(), dest.RemoteAddr())
|
|
dest.Close()
|
|
src.Close()
|
|
}
|
|
|
|
// udpProxySocket implements ProxySocket. Close() is implemented by net.UDPConn. When Close() is called,
|
|
// no new connections are allowed and existing connections are broken.
|
|
// TODO: We could lame-duck this ourselves, if it becomes important.
|
|
type udpProxySocket struct {
|
|
*net.UDPConn
|
|
port int
|
|
}
|
|
|
|
func (udp *udpProxySocket) ListenPort() int {
|
|
return udp.port
|
|
}
|
|
|
|
func (udp *udpProxySocket) Addr() net.Addr {
|
|
return udp.LocalAddr()
|
|
}
|
|
|
|
// Holds all the known UDP clients that have not timed out.
|
|
type ClientCache struct {
|
|
Mu sync.Mutex
|
|
Clients map[string]net.Conn // addr string -> connection
|
|
}
|
|
|
|
func newClientCache() *ClientCache {
|
|
return &ClientCache{Clients: map[string]net.Conn{}}
|
|
}
|
|
|
|
func (udp *udpProxySocket) ProxyLoop(service proxy.ServicePortName, myInfo *ServiceInfo, loadBalancer LoadBalancer) {
|
|
var buffer [4096]byte // 4KiB should be enough for most whole-packets
|
|
for {
|
|
if !myInfo.IsAlive() {
|
|
// The service port was closed or replaced.
|
|
break
|
|
}
|
|
|
|
// Block until data arrives.
|
|
// TODO: Accumulate a histogram of n or something, to fine tune the buffer size.
|
|
n, cliAddr, err := udp.ReadFrom(buffer[0:])
|
|
if err != nil {
|
|
if e, ok := err.(net.Error); ok {
|
|
if e.Temporary() {
|
|
glog.V(1).Infof("ReadFrom had a temporary failure: %v", err)
|
|
continue
|
|
}
|
|
}
|
|
glog.Errorf("ReadFrom failed, exiting ProxyLoop: %v", err)
|
|
break
|
|
}
|
|
// If this is a client we know already, reuse the connection and goroutine.
|
|
svrConn, err := udp.getBackendConn(myInfo.ActiveClients, cliAddr, loadBalancer, service, myInfo.Timeout)
|
|
if err != nil {
|
|
continue
|
|
}
|
|
// TODO: It would be nice to let the goroutine handle this write, but we don't
|
|
// really want to copy the buffer. We could do a pool of buffers or something.
|
|
_, err = svrConn.Write(buffer[0:n])
|
|
if err != nil {
|
|
if !logTimeout(err) {
|
|
glog.Errorf("Write failed: %v", err)
|
|
// TODO: Maybe tear down the goroutine for this client/server pair?
|
|
}
|
|
continue
|
|
}
|
|
err = svrConn.SetDeadline(time.Now().Add(myInfo.Timeout))
|
|
if err != nil {
|
|
glog.Errorf("SetDeadline failed: %v", err)
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
|
|
func (udp *udpProxySocket) getBackendConn(activeClients *ClientCache, cliAddr net.Addr, loadBalancer LoadBalancer, service proxy.ServicePortName, timeout time.Duration) (net.Conn, error) {
|
|
activeClients.Mu.Lock()
|
|
defer activeClients.Mu.Unlock()
|
|
|
|
svrConn, found := activeClients.Clients[cliAddr.String()]
|
|
if !found {
|
|
// TODO: This could spin up a new goroutine to make the outbound connection,
|
|
// and keep accepting inbound traffic.
|
|
glog.V(3).Infof("New UDP connection from %s", cliAddr)
|
|
var err error
|
|
svrConn, err = TryConnectEndpoints(service, cliAddr, "udp", loadBalancer)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if err = svrConn.SetDeadline(time.Now().Add(timeout)); err != nil {
|
|
glog.Errorf("SetDeadline failed: %v", err)
|
|
return nil, err
|
|
}
|
|
activeClients.Clients[cliAddr.String()] = svrConn
|
|
go func(cliAddr net.Addr, svrConn net.Conn, activeClients *ClientCache, timeout time.Duration) {
|
|
defer runtime.HandleCrash()
|
|
udp.proxyClient(cliAddr, svrConn, activeClients, timeout)
|
|
}(cliAddr, svrConn, activeClients, timeout)
|
|
}
|
|
return svrConn, nil
|
|
}
|
|
|
|
// This function is expected to be called as a goroutine.
|
|
// TODO: Track and log bytes copied, like TCP
|
|
func (udp *udpProxySocket) proxyClient(cliAddr net.Addr, svrConn net.Conn, activeClients *ClientCache, timeout time.Duration) {
|
|
defer svrConn.Close()
|
|
var buffer [4096]byte
|
|
for {
|
|
n, err := svrConn.Read(buffer[0:])
|
|
if err != nil {
|
|
if !logTimeout(err) {
|
|
glog.Errorf("Read failed: %v", err)
|
|
}
|
|
break
|
|
}
|
|
err = svrConn.SetDeadline(time.Now().Add(timeout))
|
|
if err != nil {
|
|
glog.Errorf("SetDeadline failed: %v", err)
|
|
break
|
|
}
|
|
n, err = udp.WriteTo(buffer[0:n], cliAddr)
|
|
if err != nil {
|
|
if !logTimeout(err) {
|
|
glog.Errorf("WriteTo failed: %v", err)
|
|
}
|
|
break
|
|
}
|
|
}
|
|
activeClients.Mu.Lock()
|
|
delete(activeClients.Clients, cliAddr.String())
|
|
activeClients.Mu.Unlock()
|
|
}
|