telebit/cmd/wsserve/wsserve.go

356 lines
10 KiB
Go

package main
import (
"context"
"crypto/tls"
"flag"
"fmt"
"log"
"net"
"net/http"
"net/url"
"os"
"strings"
"sync"
"time"
telebit "git.coolaj86.com/coolaj86/go-telebitd/mplexer"
tbDns01 "git.coolaj86.com/coolaj86/go-telebitd/mplexer/dns01"
"git.coolaj86.com/coolaj86/go-telebitd/table"
"github.com/caddyserver/certmagic"
"github.com/dgrijalva/jwt-go"
"github.com/go-acme/lego/v3/challenge"
legoDns01 "github.com/go-acme/lego/v3/challenge/dns01"
"github.com/go-acme/lego/v3/providers/dns/duckdns"
"github.com/go-acme/lego/v3/providers/dns/godaddy"
"github.com/go-chi/chi"
"github.com/gorilla/websocket"
_ "github.com/joho/godotenv/autoload"
)
var authorizer telebit.Authorizer
var httpsrv *http.Server
var apiNotFoundContent = []byte("{ \"error\": \"not found\" }\n")
var apiNotAuthorizedContent = []byte("{ \"error\": \"not authorized\" }\n")
func init() {
r := chi.NewRouter()
r.Use(func(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
fmt.Println("[debug] should be handled as websocket quickly")
next.ServeHTTP(w, r)
})
})
r.Mount("/ws", http.HandlerFunc(upgradeWebsocket))
httpsrv = &http.Server{
Handler: r,
}
}
func main() {
certpath := flag.String("acme-storage", "./acme.d/", "path to ACME storage directory")
email := flag.String("acme-email", "", "email to use for Let's Encrypt / ACME registration")
acmeAgree := flag.Bool("acme-agree", false, "agree to the terms of the ACME service provider (required)")
//acmeStaging := flag.Bool("acme-staging", false, "get fake certificates for testing")
acmeDirectory := flag.String("acme-directory", "", "ACME Directory URL")
enableHTTP01 := flag.Bool("acme-http-01", false, "enable HTTP-01 ACME challenges")
enableTLSALPN01 := flag.Bool("acme-tls-alpn-01", false, "enable TLS-ALPN-01 ACME challenges")
acmeRelay := flag.String("acme-relay", "", "the base url of the ACME DNS-01 relay, if not the same as the tunnel relay")
authURL := flag.String("auth-url", "", "the base url for authentication, if not the same as the tunnel relay")
//apiHostname := flag.String("admin-hostname", "", "the hostname used to manage clients")
token := flag.String("token", "", "a pre-generated token to give the server (instead of generating one with --secret)")
flag.Parse()
if 0 == len(*authURL) {
*authURL = os.Getenv("AUTH_URL")
}
authorizer = NewAuthorizer(*authURL)
if 0 == len(*acmeRelay) {
*acmeRelay = os.Getenv("ACME_RELAY_BASEURL")
}
provider, err := getACMEProvider(acmeRelay, token)
if nil != err {
fmt.Fprintf(os.Stderr, "%s\n", err)
os.Exit(1)
return
}
if 0 == len(*email) {
*email = os.Getenv("ACME_EMAIL")
}
fmt.Printf("Email: %q\n", *email)
acme := &telebit.ACME{
Email: *email,
StoragePath: *certpath,
Agree: *acmeAgree,
Directory: *acmeDirectory,
DNSProvider: provider,
//DNSChallengeOption: legoDns01.DNSProviderOption,
DNSChallengeOption: legoDns01.WrapPreCheck(func(domain, fqdn, value string, orig legoDns01.PreCheckFunc) (bool, error) {
ok, err := orig(fqdn, value)
if ok {
fmt.Println("[Telebit-ACME-DNS] sleeping an additional 5 seconds")
time.Sleep(5 * time.Second)
}
return ok, err
}),
EnableHTTPChallenge: *enableHTTP01,
EnableTLSALPNChallenge: *enableTLSALPN01,
}
// TODO ports
netListener, err := net.Listen("tcp", ":3020")
if err != nil {
fmt.Fprintf(os.Stderr, "Bad things are happening: %s", err)
os.Exit(1)
}
tlsListener := tls.NewListener(netListener, NewTLSConfig(acme))
httpsrv.Serve(tlsListener)
}
// NewTLSConfig returns a certmagic-enabled config
func NewTLSConfig(acme *telebit.ACME) *tls.Config {
acme.Storage = &certmagic.FileStorage{Path: acme.StoragePath}
if "" == acme.Directory {
acme.Directory = certmagic.LetsEncryptProductionCA
}
magic, err := telebit.NewCertMagic(acme)
if nil != err {
fmt.Fprintf(
os.Stderr,
"failed to initialize certificate management (discovery url? local folder perms?): %s\n",
err,
)
os.Exit(1)
}
tlsConfig := &tls.Config{
GetCertificate: func(hello *tls.ClientHelloInfo) (*tls.Certificate, error) {
return magic.GetCertificate(hello)
/*
if false {
_, _ = magic.GetCertificate(hello)
}
// TODO
// 1. call out to greenlock for validation
// 2. push challenges through http channel
// 3. receive certificates (or don't)
certbundleT, err := tls.LoadX509KeyPair("certs/fullchain.pem", "certs/privkey.pem")
certbundle := &certbundleT
if err != nil {
return nil, err
}
return certbundle, nil
*/
},
}
return tlsConfig
}
func apiNotFoundHandler(w http.ResponseWriter, r *http.Request) {
w.Write(apiNotFoundContent)
}
// NewAuthorizer TODO
func NewAuthorizer(authURL string) telebit.Authorizer {
return func(r *http.Request) (*telebit.Grants, error) {
// do we have a valid wss_client?
var tokenString string
if auth := strings.Split(r.Header.Get("Authorization"), " "); len(auth) > 1 {
// TODO handle Basic auth tokens as well
tokenString = auth[1]
}
if "" == tokenString {
// Browsers do not allow Authorization Headers and must use access_token query string
tokenString = r.URL.Query().Get("access_token")
}
if "" != r.URL.Query().Get("access_token") {
r.URL.Query().Set("access_token", "[redacted]")
}
grants, err := telebit.Inspect(authURL, tokenString)
if nil != err {
fmt.Println("[wsserve] return an error, do not go on")
return nil, err
}
if "" != r.URL.Query().Get("access_token") {
r.URL.Query().Set("access_token", "[redacted:"+grants.Subject+"]")
}
return grants, err
}
}
func upgradeWebsocket(w http.ResponseWriter, r *http.Request) {
log.Println("websocket opening ", r.RemoteAddr, " ", r.Host)
w.Header().Set("Content-Type", "application/json")
if "Upgrade" != r.Header.Get("Connection") && "WebSocket" != r.Header.Get("Upgrade") {
w.Write(apiNotFoundContent)
return
}
grants, err := authorizer(r)
if nil != err {
log.Println("WebSocket authorization failed", err)
w.Write(apiNotAuthorizedContent)
return
}
upgrader := websocket.Upgrader{
ReadBufferSize: 1024,
WriteBufferSize: 1024,
}
fmt.Println("[debug] grants", grants)
conn, err := upgrader.Upgrade(w, r, nil)
if err != nil {
log.Println("WebSocket upgrade failed", err)
return
}
wsTun := telebit.NewWebsocketTunnel(conn)
server := &table.SubscriberConn{
RemoteAddr: r.RemoteAddr,
WSConn: conn,
WSTun: wsTun,
Grants: grants,
Clients: &sync.Map{},
MultiEncoder: telebit.NewEncoder(context.TODO(), wsTun),
MultiDecoder: telebit.NewDecoder(wsTun),
}
go func() {
// (this listener is also a telebit.Router)
err := server.MultiDecoder.Decode(server)
// The tunnel itself must be closed explicitly because
// there's an encoder with a callback between the websocket
// and the multiplexer, so it doesn't know to stop listening otherwise
_ = wsTun.Close()
fmt.Printf("a subscriber stream is done: %q\n", err)
}()
table.Add(server)
}
func getACMEProvider(acmeRelay, token *string) (challenge.Provider, error) {
var err error
var provider challenge.Provider = nil
if "" != os.Getenv("GODADDY_API_KEY") {
id := os.Getenv("GODADDY_API_KEY")
apiSecret := os.Getenv("GODADDY_API_SECRET")
if provider, err = newGoDaddyDNSProvider(id, apiSecret); nil != err {
return nil, err
}
} else if "" != os.Getenv("DUCKDNS_TOKEN") {
if provider, err = newDuckDNSProvider(os.Getenv("DUCKDNS_TOKEN")); nil != err {
return nil, err
}
} else {
if "" == *acmeRelay {
return nil, fmt.Errorf("No relay for ACME DNS-01 challenges given to --acme-relay")
}
endpoint := *acmeRelay
if strings.HasSuffix(endpoint, "/") {
endpoint = endpoint[:len(endpoint)-1]
}
//endpoint += "/api/dns/"
if provider, err = newAPIDNSProvider(endpoint, *token); nil != err {
return nil, err
}
}
return provider, nil
}
// ACMEProvider TODO
type ACMEProvider struct {
BaseURL string
provider challenge.Provider
}
// Present presents a prepared ACME challenge
func (p *ACMEProvider) Present(domain, token, keyAuth string) error {
return p.provider.Present(domain, token, keyAuth)
}
// CleanUp removes a used, expired, or otherwise complete ACME challenge
func (p *ACMEProvider) CleanUp(domain, token, keyAuth string) error {
return p.provider.CleanUp(domain, token, keyAuth)
}
// newDuckDNSProvider is for the sake of demoing the tunnel
func newDuckDNSProvider(token string) (*duckdns.DNSProvider, error) {
config := duckdns.NewDefaultConfig()
config.Token = token
return duckdns.NewDNSProviderConfig(config)
}
// newGoDaddyDNSProvider is for the sake of demoing the tunnel
func newGoDaddyDNSProvider(id, secret string) (*godaddy.DNSProvider, error) {
config := godaddy.NewDefaultConfig()
config.APIKey = id
config.APISecret = secret
return godaddy.NewDNSProviderConfig(config)
}
// newAPIDNSProvider is for the sake of demoing the tunnel
func newAPIDNSProvider(baseURL string, token string) (*tbDns01.DNSProvider, error) {
config := tbDns01.NewDefaultConfig()
config.Token = token
endpoint, err := url.Parse(baseURL)
if nil != err {
return nil, err
}
config.Endpoint = endpoint
return tbDns01.NewDNSProviderConfig(config)
}
/*
// TODO for http proxy
return mplexer.TargetOptions {
Hostname // default localhost
Termination // default TLS
XFWD // default... no?
Port // default 0
Conn // should be dialed beforehand
}, nil
*/
/*
t := telebit.New(token)
mux := telebit.RouteMux{}
mux.HandleTLS("*", mux) // go back to itself
mux.HandleProxy("example.com", "localhost:3000")
mux.HandleTCP("example.com", func (c *telebit.Conn) {
return httpmux.Serve()
})
l := t.Listen("wss://example.com")
conn := l.Accept()
telebit.Serve(listener, mux)
t.ListenAndServe("wss://example.com", mux)
*/
func getToken(secret string, domains, ports []string) (token string, err error) {
tokenData := jwt.MapClaims{"domains": domains, "ports": ports}
jwtToken := jwt.NewWithClaims(jwt.SigningMethodHS256, tokenData)
if token, err = jwtToken.SignedString([]byte(secret)); err != nil {
return "", err
}
return token, nil
}