tailscale/cmd/vnet/vnet-main.go

140 lines
3.3 KiB
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
// The vnet binary runs a virtual network stack in userspace for qemu instances
// to connect to and simulate various network conditions.
package main
import (
"context"
"flag"
"log"
"net"
"net/http"
"net/http/httputil"
"net/url"
"os"
"time"
"tailscale.com/tstest/natlab/vnet"
"tailscale.com/types/logger"
"tailscale.com/util/must"
)
var (
listen = flag.String("listen", "/tmp/qemu.sock", "path to listen on")
nat = flag.String("nat", "easy", "type of NAT to use")
nat2 = flag.String("nat2", "hard", "type of NAT to use for second network")
portmap = flag.Bool("portmap", false, "enable portmapping; requires --v4")
dgram = flag.Bool("dgram", false, "enable datagram mode; for use with macOS Hypervisor.Framework and VZFileHandleNetworkDeviceAttachment")
blend = flag.Bool("blend", true, "blend reality (controlplane.tailscale.com and DERPs) into the virtual network")
pcapFile = flag.String("pcap", "", "if non-empty, filename to write pcap")
v4 = flag.Bool("v4", true, "enable IPv4")
v6 = flag.Bool("v6", true, "enable IPv6")
)
func main() {
flag.Parse()
if _, err := os.Stat(*listen); err == nil {
os.Remove(*listen)
}
var srv net.Listener
var err error
var conn *net.UnixConn
if *dgram {
addr, err := net.ResolveUnixAddr("unixgram", *listen)
if err != nil {
log.Fatalf("ResolveUnixAddr: %v", err)
}
conn, err = net.ListenUnixgram("unixgram", addr)
if err != nil {
log.Fatalf("ListenUnixgram: %v", err)
}
defer conn.Close()
} else {
srv, err = net.Listen("unix", *listen)
}
if err != nil {
log.Fatal(err)
}
var c vnet.Config
c.SetPCAPFile(*pcapFile)
c.SetBlendReality(*blend)
var net1opt = []any{vnet.NAT(*nat)}
if *v4 {
net1opt = append(net1opt, "2.1.1.1", "192.168.1.1/24")
}
if *v6 {
net1opt = append(net1opt, "2000:52::1/64")
}
node1 := c.AddNode(c.AddNetwork(net1opt...))
c.AddNode(c.AddNetwork("2.2.2.2", "10.2.0.1/16", vnet.NAT(*nat2)))
if *portmap && *v4 {
node1.Network().AddService(vnet.NATPMP)
}
s, err := vnet.New(&c)
if err != nil {
log.Fatalf("newServer: %v", err)
}
if *blend {
if err := s.PopulateDERPMapIPs(); err != nil {
log.Printf("warning: ignoring failure to populate DERP map: %v", err)
}
}
s.WriteStartingBanner(os.Stdout)
nc := s.NodeAgentClient(node1)
go func() {
rp := httputil.NewSingleHostReverseProxy(must.Get(url.Parse("http://gokrazy")))
d := rp.Director
rp.Director = func(r *http.Request) {
d(r)
r.Header.Set("X-TTA-GoKrazy", "1")
}
rp.Transport = nc.HTTPClient.Transport
http.ListenAndServe(":8080", rp)
}()
go func() {
var last string
getStatus := func() {
ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
defer cancel()
st, err := nc.Status(ctx)
if err != nil {
log.Printf("NodeStatus: %v", err)
return
}
if st.BackendState != last {
last = st.BackendState
log.Printf("NodeStatus: %v", logger.AsJSON(st))
}
}
for {
time.Sleep(5 * time.Second)
//continue
getStatus()
}
}()
if conn != nil {
s.ServeUnixConn(conn, vnet.ProtocolUnixDGRAM)
return
}
for {
c, err := srv.Accept()
if err != nil {
log.Printf("Accept: %v", err)
continue
}
go s.ServeUnixConn(c.(*net.UnixConn), vnet.ProtocolQEMU)
}
}