tailscale/cmd/hello/hello.go
2021-01-29 13:49:17 -08:00

135 lines
3.2 KiB
Go

// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// The hello binary runs hello.ipn.dev.
package main // import "tailscale.com/cmd/hello"
import (
"context"
"encoding/json"
"flag"
"fmt"
"html/template"
"io/ioutil"
"log"
"net"
"net/http"
"net/url"
"strings"
"tailscale.com/safesocket"
"tailscale.com/tailcfg"
)
var (
httpAddr = flag.String("http", ":80", "address to run an HTTP server on, or empty for none")
httpsAddr = flag.String("https", ":443", "address to run an HTTPS server on, or empty for none")
)
func main() {
flag.Parse()
http.HandleFunc("/", root)
log.Printf("Starting hello server.")
errc := make(chan error, 1)
if *httpAddr != "" {
log.Printf("running HTTP server on %s", *httpAddr)
go func() {
errc <- http.ListenAndServe(*httpAddr, nil)
}()
}
if *httpsAddr != "" {
log.Printf("running HTTPS server on %s", *httpsAddr)
go func() {
errc <- http.ListenAndServeTLS(*httpsAddr,
"/etc/hello/hello.ipn.dev.crt",
"/etc/hello/hello.ipn.dev.key",
nil,
)
}()
}
log.Fatal(<-errc)
}
func slurpHTML() string {
slurp, err := ioutil.ReadFile("hello.tmpl.html")
if err != nil {
log.Fatal(err)
}
return string(slurp)
}
var tmpl = template.Must(template.New("home").Parse(slurpHTML()))
type tmplData struct {
DisplayName string // "Foo Barberson"
LoginName string // "foo@bar.com"
MachineName string // "imac5k"
IP string // "100.2.3.4"
}
func root(w http.ResponseWriter, r *http.Request) {
if r.TLS == nil && *httpsAddr != "" {
host := r.Host
if strings.Contains(r.Host, "100.101.102.103") {
host = "hello.ipn.dev"
}
http.Redirect(w, r, "https://"+host, http.StatusFound)
return
}
if r.RequestURI != "/" {
http.Redirect(w, r, "/", http.StatusFound)
return
}
ip, _, err := net.SplitHostPort(r.RemoteAddr)
if err != nil {
http.Error(w, "no remote addr", 500)
return
}
who, err := whoIs(ip)
if err != nil {
log.Printf("whois(%q) error: %v", ip, err)
http.Error(w, "Your Tailscale works, but we failed to look you up.", 500)
return
}
w.Header().Set("Content-Type", "text/html; charset=utf-8")
tmpl.Execute(w, tmplData{
DisplayName: who.UserProfile.DisplayName,
LoginName: who.UserProfile.LoginName,
MachineName: who.Node.ComputedName,
IP: ip,
})
}
// tsSockClient does HTTP requests to the local Tailscale daemon.
// The hostname in the HTTP request is ignored.
var tsSockClient = &http.Client{
Transport: &http.Transport{
DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
return safesocket.ConnectDefault()
},
},
}
func whoIs(ip string) (*tailcfg.WhoIsResponse, error) {
res, err := tsSockClient.Get("http://local-tailscaled.sock/localapi/v0/whois?ip=" + url.QueryEscape(ip))
if err != nil {
return nil, err
}
defer res.Body.Close()
slurp, _ := ioutil.ReadAll(res.Body)
if res.StatusCode != 200 {
return nil, fmt.Errorf("HTTP %s: %s", res.Status, slurp)
}
r := new(tailcfg.WhoIsResponse)
if err := json.Unmarshal(slurp, r); err != nil {
if max := 200; len(slurp) > max {
slurp = slurp[:max]
}
return nil, fmt.Errorf("failed to parse JSON WhoIsResponse from %q", slurp)
}
return r, nil
}