gocheese.go

   1 /*
   2 GoCheese -- Python private package repository and caching proxy
   3 Copyright (C) 2019 Sergey Matveev <stargrave@stargrave.org>
   4               2019 Elena Balakhonova <balakhonova_e@riseup.net>
   5
   6 This program is free software: you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation, version 3 of the License.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 // Python private package repository and caching proxy
  20 package main
  21
  22 import (
  23         "bytes"
  24         "context"
  25         "crypto/sha256"
  26         "encoding/hex"
  27         "flag"
  28         "fmt"
  29         "io"
  30         "io/ioutil"
  31         "log"
  32         "net"
  33         "net/http"
  34         "net/url"
  35         "os"
  36         "os/signal"
  37         "path/filepath"
  38         "regexp"
  39         "runtime"
  40         "strings"
  41         "syscall"
  42         "time"
  43
  44         "golang.org/x/net/netutil"
  45 )
  46
  47 const (
  48         HTMLBegin = `<!DOCTYPE html>
  49 <html>
  50   <head>
  51     <title>Links for %s</title>
  52   </head>
  53   <body>
  54 `
  55         HTMLEnd      = "  </body>\n</html>\n"
  56         HTMLElement  = "    <a href=\"%s\"%s>%s</a><br/>\n"
  57         SHA256Prefix = "sha256="
  58         SHA256Ext    = ".sha256"
  59         InternalFlag = ".internal"
  60         GPGSigExt    = ".asc"
  61         GPGSigAttr   = " data-gpg-sig=true"
  62
  63         Warranty = `This program is free software: you can redistribute it and/or modify
  64 it under the terms of the GNU General Public License as published by
  65 the Free Software Foundation, version 3 of the License.
  66
  67 This program is distributed in the hope that it will be useful,
  68 but WITHOUT ANY WARRANTY; without even the implied warranty of
  69 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  70 GNU General Public License for more details.
  71
  72 You should have received a copy of the GNU General Public License
  73 along with this program.  If not, see <http://www.gnu.org/licenses/>.`
  74 )
  75
  76 var (
  77         pkgPyPI        = regexp.MustCompile(`^.*<a href="([^"]+)"[^>]*>(.+)</a><br/>.*$`)
  78         Version string = "UNKNOWN"
  79
  80         root             = flag.String("root", "./packages", "Path to packages directory")
  81         bind             = flag.String("bind", "[::]:8080", "Address to bind to")
  82         tlsCert          = flag.String("tls-cert", "", "Path to TLS X.509 certificate")
  83         tlsKey           = flag.String("tls-key", "", "Path to TLS X.509 private key")
  84         norefreshURLPath = flag.String("norefresh", "/norefresh/", "Non-refreshing URL path")
  85         refreshURLPath   = flag.String("refresh", "/simple/", "Auto-refreshing URL path")
  86         gpgUpdateURLPath = flag.String("gpgupdate", "/gpgupdate/", "GPG forceful refreshing URL path")
  87         pypiURL          = flag.String("pypi", "https://pypi.org/simple/", "Upstream PyPI URL")
  88         passwdPath       = flag.String("passwd", "passwd", "Path to file with authenticators")
  89         passwdCheck      = flag.Bool("passwd-check", false, "Test the -passwd file for syntax errors and exit")
  90         fsck             = flag.Bool("fsck", false, "Check integrity of all packages")
  91         maxClients       = flag.Int("maxclients", 128, "Maximal amount of simultaneous clients")
  92         version          = flag.Bool("version", false, "Print version information")
  93         warranty         = flag.Bool("warranty", false, "Print warranty information")
  94
  95         killed bool
  96
  97         normalizationRe *regexp.Regexp = regexp.MustCompilePOSIX("[-_.]+")
  98 )
  99
 100 func mkdirForPkg(w http.ResponseWriter, r *http.Request, dir string) bool {
 101         path := filepath.Join(*root, dir)
 102         if _, err := os.Stat(path); os.IsNotExist(err) {
 103                 if err = os.Mkdir(path, os.FileMode(0777)); err != nil {
 104                         http.Error(w, err.Error(), http.StatusInternalServerError)
 105                         return false
 106                 }
 107                 log.Println(r.RemoteAddr, "mkdir", dir)
 108         }
 109         return true
 110 }
 111
 112 func refreshDir(
 113         w http.ResponseWriter,
 114         r *http.Request,
 115         dir,
 116         filenameGet string,
 117         gpgUpdate bool,
 118 ) bool {
 119         if _, err := os.Stat(filepath.Join(*root, dir, InternalFlag)); err == nil {
 120                 return true
 121         }
 122         resp, err := http.Get(*pypiURL + dir + "/")
 123         if err != nil {
 124                 http.Error(w, err.Error(), http.StatusBadGateway)
 125                 return false
 126         }
 127         body, err := ioutil.ReadAll(resp.Body)
 128         resp.Body.Close()
 129         if err != nil {
 130                 http.Error(w, err.Error(), http.StatusBadGateway)
 131                 return false
 132         }
 133         if !mkdirForPkg(w, r, dir) {
 134                 return false
 135         }
 136         dirPath := filepath.Join(*root, dir)
 137         var submatches []string
 138         var uri string
 139         var filename string
 140         var path string
 141         var pkgURL *url.URL
 142         var digest []byte
 143         for _, lineRaw := range bytes.Split(body, []byte("\n")) {
 144                 submatches = pkgPyPI.FindStringSubmatch(string(lineRaw))
 145                 if len(submatches) == 0 {
 146                         continue
 147                 }
 148                 uri = submatches[1]
 149                 filename = submatches[2]
 150                 if pkgURL, err = url.Parse(uri); err != nil {
 151                         http.Error(w, err.Error(), http.StatusInternalServerError)
 152                         return false
 153                 }
 154                 digest, err = hex.DecodeString(strings.TrimPrefix(pkgURL.Fragment, SHA256Prefix))
 155                 if err != nil {
 156                         http.Error(w, err.Error(), http.StatusBadGateway)
 157                         return false
 158                 }
 159                 pkgURL.Fragment = ""
 160                 path = filepath.Join(dirPath, filename)
 161                 if filename == filenameGet {
 162                         if killed {
 163                                 // Skip heavy remote call, when shutting down
 164                                 http.Error(w, "shutting down", http.StatusInternalServerError)
 165                                 return false
 166                         }
 167                         log.Println(r.RemoteAddr, "pypi download", filename)
 168                         resp, err = http.Get(pkgURL.String())
 169                         if err != nil {
 170                                 http.Error(w, err.Error(), http.StatusBadGateway)
 171                                 return false
 172                         }
 173                         defer resp.Body.Close()
 174                         hasher := sha256.New()
 175                         dst, err := TempFile(dirPath)
 176                         if err != nil {
 177                                 http.Error(w, err.Error(), http.StatusInternalServerError)
 178                                 return false
 179                         }
 180                         wr := io.MultiWriter(hasher, dst)
 181                         if _, err = io.Copy(wr, resp.Body); err != nil {
 182                                 os.Remove(dst.Name())
 183                                 dst.Close()
 184                                 http.Error(w, err.Error(), http.StatusInternalServerError)
 185                                 return false
 186                         }
 187                         if bytes.Compare(hasher.Sum(nil), digest) != 0 {
 188                                 log.Println(r.RemoteAddr, "pypi", filename, "digest mismatch")
 189                                 os.Remove(dst.Name())
 190                                 dst.Close()
 191                                 http.Error(w, err.Error(), http.StatusBadGateway)
 192                                 return false
 193                         }
 194                         if err = dst.Sync(); err != nil {
 195                                 os.Remove(dst.Name())
 196                                 dst.Close()
 197                                 http.Error(w, err.Error(), http.StatusInternalServerError)
 198                                 return false
 199                         }
 200                         dst.Close()
 201                         if err = os.Rename(dst.Name(), path); err != nil {
 202                                 http.Error(w, err.Error(), http.StatusInternalServerError)
 203                                 return false
 204                         }
 205                         if err = DirSync(dirPath); err != nil {
 206                                 http.Error(w, err.Error(), http.StatusInternalServerError)
 207                                 return false
 208                         }
 209                 }
 210                 if filename == filenameGet || gpgUpdate {
 211                         if _, err = os.Stat(path); err != nil {
 212                                 goto GPGSigSkip
 213                         }
 214                         resp, err := http.Get(pkgURL.String() + GPGSigExt)
 215                         if err != nil {
 216                                 goto GPGSigSkip
 217                         }
 218                         if resp.StatusCode != http.StatusOK {
 219                                 resp.Body.Close()
 220                                 goto GPGSigSkip
 221                         }
 222                         sig, err := ioutil.ReadAll(resp.Body)
 223                         resp.Body.Close()
 224                         if err != nil {
 225                                 goto GPGSigSkip
 226                         }
 227                         if err = WriteFileSync(dirPath, path+GPGSigExt, sig); err != nil {
 228                                 http.Error(w, err.Error(), http.StatusInternalServerError)
 229                                 return false
 230                         }
 231                         log.Println(r.RemoteAddr, "pypi downloaded signature", filename)
 232                 }
 233         GPGSigSkip:
 234                 path = path + SHA256Ext
 235                 _, err = os.Stat(path)
 236                 if err == nil {
 237                         continue
 238                 }
 239                 if !os.IsNotExist(err) {
 240                         http.Error(w, err.Error(), http.StatusInternalServerError)
 241                         return false
 242                 }
 243                 log.Println(r.RemoteAddr, "pypi touch", filename)
 244                 if err = WriteFileSync(dirPath, path, digest); err != nil {
 245                         http.Error(w, err.Error(), http.StatusInternalServerError)
 246                         return false
 247                 }
 248         }
 249         return true
 250 }
 251
 252 func listRoot(w http.ResponseWriter, r *http.Request) {
 253         files, err := ioutil.ReadDir(*root)
 254         if err != nil {
 255                 http.Error(w, err.Error(), http.StatusInternalServerError)
 256                 return
 257         }
 258         var result bytes.Buffer
 259         result.WriteString(fmt.Sprintf(HTMLBegin, "root"))
 260         for _, file := range files {
 261                 if file.Mode().IsDir() {
 262                         result.WriteString(fmt.Sprintf(
 263                                 HTMLElement,
 264                                 *refreshURLPath+file.Name()+"/",
 265                                 file.Name(),
 266                         ))
 267                 }
 268         }
 269         result.WriteString(HTMLEnd)
 270         w.Write(result.Bytes())
 271 }
 272
 273 func listDir(
 274         w http.ResponseWriter,
 275         r *http.Request,
 276         dir string,
 277         autorefresh,
 278         gpgUpdate bool,
 279 ) {
 280         dirPath := filepath.Join(*root, dir)
 281         if autorefresh {
 282                 if !refreshDir(w, r, dir, "", gpgUpdate) {
 283                         return
 284                 }
 285         } else if _, err := os.Stat(dirPath); os.IsNotExist(err) && !refreshDir(w, r, dir, "", false) {
 286                 return
 287         }
 288         files, err := ioutil.ReadDir(dirPath)
 289         if err != nil {
 290                 http.Error(w, err.Error(), http.StatusInternalServerError)
 291                 return
 292         }
 293         var result bytes.Buffer
 294         result.WriteString(fmt.Sprintf(HTMLBegin, dir))
 295         var data []byte
 296         var gpgSigAttr string
 297         var filenameClean string
 298         for _, file := range files {
 299                 if !strings.HasSuffix(file.Name(), SHA256Ext) {
 300                         continue
 301                 }
 302                 if killed {
 303                         // Skip expensive I/O when shutting down
 304                         http.Error(w, "shutting down", http.StatusInternalServerError)
 305                         return
 306                 }
 307                 data, err = ioutil.ReadFile(filepath.Join(dirPath, file.Name()))
 308                 if err != nil {
 309                         http.Error(w, err.Error(), http.StatusInternalServerError)
 310                         return
 311                 }
 312                 filenameClean = strings.TrimSuffix(file.Name(), SHA256Ext)
 313                 if _, err = os.Stat(filepath.Join(dirPath, filenameClean+GPGSigExt)); os.IsNotExist(err) {
 314                         gpgSigAttr = ""
 315                 } else {
 316                         gpgSigAttr = GPGSigAttr
 317                 }
 318                 result.WriteString(fmt.Sprintf(
 319                         HTMLElement,
 320                         strings.Join([]string{
 321                                 *refreshURLPath, dir, "/",
 322                                 filenameClean, "#", SHA256Prefix, hex.EncodeToString(data),
 323                         }, ""),
 324                         gpgSigAttr,
 325                         filenameClean,
 326                 ))
 327         }
 328         result.WriteString(HTMLEnd)
 329         w.Write(result.Bytes())
 330 }
 331
 332 func servePkg(w http.ResponseWriter, r *http.Request, dir, filename string) {
 333         log.Println(r.RemoteAddr, "get", filename)
 334         path := filepath.Join(*root, dir, filename)
 335         if _, err := os.Stat(path); os.IsNotExist(err) {
 336                 if !refreshDir(w, r, dir, filename, false) {
 337                         return
 338                 }
 339         }
 340         http.ServeFile(w, r, path)
 341 }
 342
 343 func serveUpload(w http.ResponseWriter, r *http.Request) {
 344         // Authentication
 345         username, password, ok := r.BasicAuth()
 346         if !ok {
 347                 log.Println(r.RemoteAddr, "unauthenticated", username)
 348                 http.Error(w, "unauthenticated", http.StatusUnauthorized)
 349                 return
 350         }
 351         auther, ok := passwords[username]
 352         if !ok || !auther.Auth(password) {
 353                 log.Println(r.RemoteAddr, "unauthenticated", username)
 354                 http.Error(w, "unauthenticated", http.StatusUnauthorized)
 355                 return
 356         }
 357
 358         // Form parsing
 359         var err error
 360         if err = r.ParseMultipartForm(1 << 20); err != nil {
 361                 http.Error(w, err.Error(), http.StatusBadRequest)
 362                 return
 363         }
 364         pkgNames, exists := r.MultipartForm.Value["name"]
 365         if !exists || len(pkgNames) != 1 {
 366                 http.Error(w, "single name is expected in request", http.StatusBadRequest)
 367                 return
 368         }
 369         dir := normalizationRe.ReplaceAllString(pkgNames[0], "-")
 370         dirPath := filepath.Join(*root, dir)
 371         var digestExpected []byte
 372         if digestExpectedHex, exists := r.MultipartForm.Value["sha256_digest"]; exists {
 373                 digestExpected, err = hex.DecodeString(digestExpectedHex[0])
 374                 if err != nil {
 375                         http.Error(w, "bad sha256_digest: "+err.Error(), http.StatusBadRequest)
 376                         return
 377                 }
 378         }
 379         gpgSigsExpected := make(map[string]struct{})
 380
 381         // Checking is it internal package
 382         if _, err = os.Stat(filepath.Join(dirPath, InternalFlag)); err != nil {
 383                 log.Println(r.RemoteAddr, "non-internal package", dir)
 384                 http.Error(w, "unknown internal package", http.StatusUnauthorized)
 385                 return
 386         }
 387
 388         for _, file := range r.MultipartForm.File["content"] {
 389                 filename := file.Filename
 390                 gpgSigsExpected[filename+GPGSigExt] = struct{}{}
 391                 log.Println(r.RemoteAddr, "put", filename, "by", username)
 392                 path := filepath.Join(dirPath, filename)
 393                 if _, err = os.Stat(path); err == nil {
 394                         log.Println(r.RemoteAddr, "already exists", filename)
 395                         http.Error(w, "already exists", http.StatusBadRequest)
 396                         return
 397                 }
 398                 if !mkdirForPkg(w, r, dir) {
 399                         return
 400                 }
 401                 src, err := file.Open()
 402                 defer src.Close()
 403                 if err != nil {
 404                         http.Error(w, err.Error(), http.StatusInternalServerError)
 405                         return
 406                 }
 407                 dst, err := TempFile(dirPath)
 408                 if err != nil {
 409                         http.Error(w, err.Error(), http.StatusInternalServerError)
 410                         return
 411                 }
 412                 hasher := sha256.New()
 413                 wr := io.MultiWriter(hasher, dst)
 414                 if _, err = io.Copy(wr, src); err != nil {
 415                         os.Remove(dst.Name())
 416                         dst.Close()
 417                         http.Error(w, err.Error(), http.StatusInternalServerError)
 418                         return
 419                 }
 420                 if err = dst.Sync(); err != nil {
 421                         os.Remove(dst.Name())
 422                         dst.Close()
 423                         http.Error(w, err.Error(), http.StatusInternalServerError)
 424                         return
 425                 }
 426                 dst.Close()
 427                 digest := hasher.Sum(nil)
 428                 if digestExpected != nil {
 429                         if bytes.Compare(digestExpected, digest) == 0 {
 430                                 log.Println(r.RemoteAddr, filename, "good checksum received")
 431                         } else {
 432                                 log.Println(r.RemoteAddr, filename, "bad checksum received")
 433                                 http.Error(w, "bad checksum", http.StatusBadRequest)
 434                                 os.Remove(dst.Name())
 435                                 return
 436                         }
 437                 }
 438                 if err = os.Rename(dst.Name(), path); err != nil {
 439                         http.Error(w, err.Error(), http.StatusInternalServerError)
 440                         return
 441                 }
 442                 if err = DirSync(dirPath); err != nil {
 443                         http.Error(w, err.Error(), http.StatusInternalServerError)
 444                         return
 445                 }
 446                 if err = WriteFileSync(dirPath, path+SHA256Ext, digest); err != nil {
 447                         http.Error(w, err.Error(), http.StatusInternalServerError)
 448                         return
 449                 }
 450         }
 451         for _, file := range r.MultipartForm.File["gpg_signature"] {
 452                 filename := file.Filename
 453                 if _, exists := gpgSigsExpected[filename]; !exists {
 454                         http.Error(w, "unexpected GPG signature filename", http.StatusBadRequest)
 455                         return
 456                 }
 457                 delete(gpgSigsExpected, filename)
 458                 log.Println(r.RemoteAddr, "put", filename, "by", username)
 459                 path := filepath.Join(dirPath, filename)
 460                 if _, err = os.Stat(path); err == nil {
 461                         log.Println(r.RemoteAddr, "already exists", filename)
 462                         http.Error(w, "already exists", http.StatusBadRequest)
 463                         return
 464                 }
 465                 src, err := file.Open()
 466                 if err != nil {
 467                         http.Error(w, err.Error(), http.StatusInternalServerError)
 468                         return
 469                 }
 470                 sig, err := ioutil.ReadAll(src)
 471                 src.Close()
 472                 if err != nil {
 473                         http.Error(w, err.Error(), http.StatusInternalServerError)
 474                         return
 475                 }
 476                 if err = WriteFileSync(dirPath, path, sig); err != nil {
 477                         http.Error(w, err.Error(), http.StatusInternalServerError)
 478                         return
 479                 }
 480         }
 481 }
 482
 483 func handler(w http.ResponseWriter, r *http.Request) {
 484         switch r.Method {
 485         case "GET":
 486                 var path string
 487                 var autorefresh bool
 488                 var gpgUpdate bool
 489                 if strings.HasPrefix(r.URL.Path, *norefreshURLPath) {
 490                         path = strings.TrimPrefix(r.URL.Path, *norefreshURLPath)
 491                 } else if strings.HasPrefix(r.URL.Path, *refreshURLPath) {
 492                         path = strings.TrimPrefix(r.URL.Path, *refreshURLPath)
 493                         autorefresh = true
 494                 } else if strings.HasPrefix(r.URL.Path, *gpgUpdateURLPath) {
 495                         path = strings.TrimPrefix(r.URL.Path, *gpgUpdateURLPath)
 496                         autorefresh = true
 497                         gpgUpdate = true
 498                 } else {
 499                         http.Error(w, "unknown action", http.StatusBadRequest)
 500                         return
 501                 }
 502                 parts := strings.Split(strings.TrimSuffix(path, "/"), "/")
 503                 if len(parts) > 2 {
 504                         http.Error(w, "invalid path", http.StatusBadRequest)
 505                         return
 506                 }
 507                 if len(parts) == 1 {
 508                         if parts[0] == "" {
 509                                 listRoot(w, r)
 510                         } else {
 511                                 listDir(w, r, parts[0], autorefresh, gpgUpdate)
 512                         }
 513                 } else {
 514                         servePkg(w, r, parts[0], parts[1])
 515                 }
 516         case "POST":
 517                 serveUpload(w, r)
 518         default:
 519                 http.Error(w, "unknown action", http.StatusBadRequest)
 520         }
 521 }
 522
 523 func goodIntegrity() bool {
 524         dirs, err := ioutil.ReadDir(*root)
 525         if err != nil {
 526                 log.Fatal(err)
 527         }
 528         hasher := sha256.New()
 529         digest := make([]byte, sha256.Size)
 530         isGood := true
 531         var data []byte
 532         var pkgName string
 533         for _, dir := range dirs {
 534                 files, err := ioutil.ReadDir(filepath.Join(*root, dir.Name()))
 535                 if err != nil {
 536                         log.Fatal(err)
 537                 }
 538                 for _, file := range files {
 539                         if !strings.HasSuffix(file.Name(), SHA256Ext) {
 540                                 continue
 541                         }
 542                         pkgName = strings.TrimSuffix(file.Name(), SHA256Ext)
 543                         data, err = ioutil.ReadFile(filepath.Join(*root, dir.Name(), pkgName))
 544                         if err != nil {
 545                                 if os.IsNotExist(err) {
 546                                         continue
 547                                 }
 548                                 log.Fatal(err)
 549                         }
 550                         hasher.Write(data)
 551                         data, err = ioutil.ReadFile(filepath.Join(*root, dir.Name(), file.Name()))
 552                         if err != nil {
 553                                 log.Fatal(err)
 554                         }
 555                         if bytes.Compare(hasher.Sum(digest[:0]), data) == 0 {
 556                                 log.Println(pkgName, "GOOD")
 557                         } else {
 558                                 isGood = false
 559                                 log.Println(pkgName, "BAD")
 560                         }
 561                         hasher.Reset()
 562                 }
 563         }
 564         return isGood
 565 }
 566
 567 func main() {
 568         flag.Parse()
 569         if *warranty {
 570                 fmt.Println(Warranty)
 571                 return
 572         }
 573         if *version {
 574                 fmt.Println("GoCheese version " + Version + " built with " + runtime.Version())
 575                 return
 576         }
 577         if *fsck {
 578                 if !goodIntegrity() {
 579                         os.Exit(1)
 580                 }
 581                 return
 582         }
 583         if *passwdCheck {
 584                 refreshPasswd()
 585                 return
 586         }
 587         if (*tlsCert != "" && *tlsKey == "") || (*tlsCert == "" && *tlsKey != "") {
 588                 log.Fatalln("Both -tls-cert and -tls-key are required")
 589         }
 590         refreshPasswd()
 591         log.Println("root:", *root, "bind:", *bind)
 592
 593         ln, err := net.Listen("tcp", *bind)
 594         if err != nil {
 595                 log.Fatal(err)
 596         }
 597         ln = netutil.LimitListener(ln, *maxClients)
 598         server := &http.Server{
 599                 ReadTimeout:  time.Minute,
 600                 WriteTimeout: time.Minute,
 601         }
 602         http.HandleFunc(*norefreshURLPath, handler)
 603         http.HandleFunc(*refreshURLPath, handler)
 604         http.HandleFunc(*gpgUpdateURLPath, handler)
 605
 606         needsRefreshPasswd := make(chan os.Signal, 0)
 607         needsShutdown := make(chan os.Signal, 0)
 608         exitErr := make(chan error, 0)
 609         signal.Notify(needsRefreshPasswd, syscall.SIGHUP)
 610         signal.Notify(needsShutdown, syscall.SIGTERM, syscall.SIGINT)
 611         go func() {
 612                 for range needsRefreshPasswd {
 613                         log.Println("Refreshing passwords")
 614                         refreshPasswd()
 615                 }
 616         }()
 617         go func(s *http.Server) {
 618                 <-needsShutdown
 619                 killed = true
 620                 log.Println("Shutting down")
 621                 ctx, cancel := context.WithTimeout(context.TODO(), time.Minute)
 622                 exitErr <- s.Shutdown(ctx)
 623                 cancel()
 624         }(server)
 625
 626         if *tlsCert == "" {
 627                 err = server.Serve(ln)
 628         } else {
 629                 err = server.ServeTLS(ln, *tlsCert, *tlsKey)
 630         }
 631         if err != http.ErrServerClosed {
 632                 log.Fatal(err)
 633         }
 634         if err := <-exitErr; err != nil {
 635                 log.Fatal(err)
 636         }
 637 }