services/keepproxy/keepproxy.go

   1 // Copyright (C) The Arvados Authors. All rights reserved.
   2 //
   3 // SPDX-License-Identifier: AGPL-3.0
   4
   5 package main
   6
   7 import (
   8         "errors"
   9         "flag"
  10         "fmt"
  11         "io"
  12         "io/ioutil"
  13         "net"
  14         "net/http"
  15         "os"
  16         "os/signal"
  17         "regexp"
  18         "strings"
  19         "sync"
  20         "syscall"
  21         "time"
  22
  23         "git.curoverse.com/arvados.git/sdk/go/arvados"
  24         "git.curoverse.com/arvados.git/sdk/go/arvadosclient"
  25         "git.curoverse.com/arvados.git/sdk/go/config"
  26         "git.curoverse.com/arvados.git/sdk/go/health"
  27         "git.curoverse.com/arvados.git/sdk/go/httpserver"
  28         "git.curoverse.com/arvados.git/sdk/go/keepclient"
  29         log "github.com/Sirupsen/logrus"
  30         "github.com/coreos/go-systemd/daemon"
  31         "github.com/ghodss/yaml"
  32         "github.com/gorilla/mux"
  33 )
  34
  35 type Config struct {
  36         Client          arvados.Client
  37         Listen          string
  38         DisableGet      bool
  39         DisablePut      bool
  40         DefaultReplicas int
  41         Timeout         arvados.Duration
  42         PIDFile         string
  43         Debug           bool
  44         ManagementToken string
  45 }
  46
  47 func DefaultConfig() *Config {
  48         return &Config{
  49                 Listen:  ":25107",
  50                 Timeout: arvados.Duration(15 * time.Second),
  51         }
  52 }
  53
  54 var (
  55         listener net.Listener
  56         router   http.Handler
  57 )
  58
  59 const rfc3339NanoFixed = "2006-01-02T15:04:05.000000000Z07:00"
  60
  61 func main() {
  62         log.SetFormatter(&log.JSONFormatter{
  63                 TimestampFormat: rfc3339NanoFixed,
  64         })
  65
  66         cfg := DefaultConfig()
  67
  68         flagset := flag.NewFlagSet("keepproxy", flag.ExitOnError)
  69         flagset.Usage = usage
  70
  71         const deprecated = " (DEPRECATED -- use config file instead)"
  72         flagset.StringVar(&cfg.Listen, "listen", cfg.Listen, "Local port to listen on."+deprecated)
  73         flagset.BoolVar(&cfg.DisableGet, "no-get", cfg.DisableGet, "Disable GET operations."+deprecated)
  74         flagset.BoolVar(&cfg.DisablePut, "no-put", cfg.DisablePut, "Disable PUT operations."+deprecated)
  75         flagset.IntVar(&cfg.DefaultReplicas, "default-replicas", cfg.DefaultReplicas, "Default number of replicas to write if not specified by the client. If 0, use site default."+deprecated)
  76         flagset.StringVar(&cfg.PIDFile, "pid", cfg.PIDFile, "Path to write pid file."+deprecated)
  77         timeoutSeconds := flagset.Int("timeout", int(time.Duration(cfg.Timeout)/time.Second), "Timeout (in seconds) on requests to internal Keep services."+deprecated)
  78         flagset.StringVar(&cfg.ManagementToken, "management-token", cfg.ManagementToken, "Authorization token to be included in all health check requests.")
  79
  80         var cfgPath string
  81         const defaultCfgPath = "/etc/arvados/keepproxy/keepproxy.yml"
  82         flagset.StringVar(&cfgPath, "config", defaultCfgPath, "Configuration file `path`")
  83         dumpConfig := flagset.Bool("dump-config", false, "write current configuration to stdout and exit")
  84         flagset.Parse(os.Args[1:])
  85
  86         err := config.LoadFile(cfg, cfgPath)
  87         if err != nil {
  88                 h := os.Getenv("ARVADOS_API_HOST")
  89                 t := os.Getenv("ARVADOS_API_TOKEN")
  90                 if h == "" || t == "" || !os.IsNotExist(err) || cfgPath != defaultCfgPath {
  91                         log.Fatal(err)
  92                 }
  93                 log.Print("DEPRECATED: No config file found, but ARVADOS_API_HOST and ARVADOS_API_TOKEN environment variables are set. Please use a config file instead.")
  94                 cfg.Client.APIHost = h
  95                 cfg.Client.AuthToken = t
  96                 if regexp.MustCompile("^(?i:1|yes|true)$").MatchString(os.Getenv("ARVADOS_API_HOST_INSECURE")) {
  97                         cfg.Client.Insecure = true
  98                 }
  99                 if y, err := yaml.Marshal(cfg); err == nil && !*dumpConfig {
 100                         log.Print("Current configuration:\n", string(y))
 101                 }
 102                 cfg.Timeout = arvados.Duration(time.Duration(*timeoutSeconds) * time.Second)
 103         }
 104
 105         if *dumpConfig {
 106                 log.Fatal(config.DumpAndExit(cfg))
 107         }
 108
 109         arv, err := arvadosclient.New(&cfg.Client)
 110         if err != nil {
 111                 log.Fatalf("Error setting up arvados client %s", err.Error())
 112         }
 113
 114         if cfg.Debug {
 115                 keepclient.DebugPrintf = log.Printf
 116         }
 117         kc, err := keepclient.MakeKeepClient(arv)
 118         if err != nil {
 119                 log.Fatalf("Error setting up keep client %s", err.Error())
 120         }
 121         keepclient.RefreshServiceDiscoveryOnSIGHUP()
 122
 123         if cfg.PIDFile != "" {
 124                 f, err := os.Create(cfg.PIDFile)
 125                 if err != nil {
 126                         log.Fatal(err)
 127                 }
 128                 defer f.Close()
 129                 err = syscall.Flock(int(f.Fd()), syscall.LOCK_EX|syscall.LOCK_NB)
 130                 if err != nil {
 131                         log.Fatalf("flock(%s): %s", cfg.PIDFile, err)
 132                 }
 133                 defer os.Remove(cfg.PIDFile)
 134                 err = f.Truncate(0)
 135                 if err != nil {
 136                         log.Fatalf("truncate(%s): %s", cfg.PIDFile, err)
 137                 }
 138                 _, err = fmt.Fprint(f, os.Getpid())
 139                 if err != nil {
 140                         log.Fatalf("write(%s): %s", cfg.PIDFile, err)
 141                 }
 142                 err = f.Sync()
 143                 if err != nil {
 144                         log.Fatal("sync(%s): %s", cfg.PIDFile, err)
 145                 }
 146         }
 147
 148         if cfg.DefaultReplicas > 0 {
 149                 kc.Want_replicas = cfg.DefaultReplicas
 150         }
 151
 152         listener, err = net.Listen("tcp", cfg.Listen)
 153         if err != nil {
 154                 log.Fatalf("listen(%s): %s", cfg.Listen, err)
 155         }
 156         if _, err := daemon.SdNotify(false, "READY=1"); err != nil {
 157                 log.Printf("Error notifying init daemon: %v", err)
 158         }
 159         log.Println("Listening at", listener.Addr())
 160
 161         // Shut down the server gracefully (by closing the listener)
 162         // if SIGTERM is received.
 163         term := make(chan os.Signal, 1)
 164         go func(sig <-chan os.Signal) {
 165                 s := <-sig
 166                 log.Println("caught signal:", s)
 167                 listener.Close()
 168         }(term)
 169         signal.Notify(term, syscall.SIGTERM)
 170         signal.Notify(term, syscall.SIGINT)
 171
 172         // Start serving requests.
 173         router = MakeRESTRouter(!cfg.DisableGet, !cfg.DisablePut, kc, time.Duration(cfg.Timeout), cfg.ManagementToken)
 174         http.Serve(listener, httpserver.AddRequestIDs(httpserver.LogRequests(router)))
 175
 176         log.Println("shutting down")
 177 }
 178
 179 type ApiTokenCache struct {
 180         tokens     map[string]int64
 181         lock       sync.Mutex
 182         expireTime int64
 183 }
 184
 185 // Cache the token and set an expire time.  If we already have an expire time
 186 // on the token, it is not updated.
 187 func (this *ApiTokenCache) RememberToken(token string) {
 188         this.lock.Lock()
 189         defer this.lock.Unlock()
 190
 191         now := time.Now().Unix()
 192         if this.tokens[token] == 0 {
 193                 this.tokens[token] = now + this.expireTime
 194         }
 195 }
 196
 197 // Check if the cached token is known and still believed to be valid.
 198 func (this *ApiTokenCache) RecallToken(token string) bool {
 199         this.lock.Lock()
 200         defer this.lock.Unlock()
 201
 202         now := time.Now().Unix()
 203         if this.tokens[token] == 0 {
 204                 // Unknown token
 205                 return false
 206         } else if now < this.tokens[token] {
 207                 // Token is known and still valid
 208                 return true
 209         } else {
 210                 // Token is expired
 211                 this.tokens[token] = 0
 212                 return false
 213         }
 214 }
 215
 216 func GetRemoteAddress(req *http.Request) string {
 217         if xff := req.Header.Get("X-Forwarded-For"); xff != "" {
 218                 return xff + "," + req.RemoteAddr
 219         }
 220         return req.RemoteAddr
 221 }
 222
 223 func CheckAuthorizationHeader(kc *keepclient.KeepClient, cache *ApiTokenCache, req *http.Request) (pass bool, tok string) {
 224         var auth string
 225         if auth = req.Header.Get("Authorization"); auth == "" {
 226                 return false, ""
 227         }
 228
 229         _, err := fmt.Sscanf(auth, "OAuth2 %s", &tok)
 230         if err != nil {
 231                 // Scanning error
 232                 return false, ""
 233         }
 234
 235         if cache.RecallToken(tok) {
 236                 // Valid in the cache, short circuit
 237                 return true, tok
 238         }
 239
 240         arv := *kc.Arvados
 241         arv.ApiToken = tok
 242         if err := arv.Call("HEAD", "users", "", "current", nil, nil); err != nil {
 243                 log.Printf("%s: CheckAuthorizationHeader error: %v", GetRemoteAddress(req), err)
 244                 return false, ""
 245         }
 246
 247         // Success!  Update cache
 248         cache.RememberToken(tok)
 249
 250         return true, tok
 251 }
 252
 253 type proxyHandler struct {
 254         http.Handler
 255         *keepclient.KeepClient
 256         *ApiTokenCache
 257         timeout   time.Duration
 258         transport *http.Transport
 259 }
 260
 261 // MakeRESTRouter returns an http.Handler that passes GET and PUT
 262 // requests to the appropriate handlers.
 263 func MakeRESTRouter(enable_get bool, enable_put bool, kc *keepclient.KeepClient, timeout time.Duration, mgmtToken string) http.Handler {
 264         rest := mux.NewRouter()
 265
 266         transport := *(http.DefaultTransport.(*http.Transport))
 267         transport.DialContext = (&net.Dialer{
 268                 Timeout:   keepclient.DefaultConnectTimeout,
 269                 KeepAlive: keepclient.DefaultKeepAlive,
 270                 DualStack: true,
 271         }).DialContext
 272         transport.TLSClientConfig = arvadosclient.MakeTLSConfig(kc.Arvados.ApiInsecure)
 273         transport.TLSHandshakeTimeout = keepclient.DefaultTLSHandshakeTimeout
 274
 275         h := &proxyHandler{
 276                 Handler:    rest,
 277                 KeepClient: kc,
 278                 timeout:    timeout,
 279                 transport:  &transport,
 280                 ApiTokenCache: &ApiTokenCache{
 281                         tokens:     make(map[string]int64),
 282                         expireTime: 300,
 283                 },
 284         }
 285
 286         if enable_get {
 287                 rest.HandleFunc(`/{locator:[0-9a-f]{32}\+.*}`, h.Get).Methods("GET", "HEAD")
 288                 rest.HandleFunc(`/{locator:[0-9a-f]{32}}`, h.Get).Methods("GET", "HEAD")
 289
 290                 // List all blocks
 291                 rest.HandleFunc(`/index`, h.Index).Methods("GET")
 292
 293                 // List blocks whose hash has the given prefix
 294                 rest.HandleFunc(`/index/{prefix:[0-9a-f]{0,32}}`, h.Index).Methods("GET")
 295         }
 296
 297         if enable_put {
 298                 rest.HandleFunc(`/{locator:[0-9a-f]{32}\+.*}`, h.Put).Methods("PUT")
 299                 rest.HandleFunc(`/{locator:[0-9a-f]{32}}`, h.Put).Methods("PUT")
 300                 rest.HandleFunc(`/`, h.Put).Methods("POST")
 301                 rest.HandleFunc(`/{any}`, h.Options).Methods("OPTIONS")
 302                 rest.HandleFunc(`/`, h.Options).Methods("OPTIONS")
 303         }
 304
 305         rest.Handle("/_health/{check}", &health.Handler{
 306                 Token:  mgmtToken,
 307                 Prefix: "/_health/",
 308         }).Methods("GET")
 309
 310         rest.NotFoundHandler = InvalidPathHandler{}
 311         return h
 312 }
 313
 314 var errLoopDetected = errors.New("loop detected")
 315
 316 func (*proxyHandler) checkLoop(resp http.ResponseWriter, req *http.Request) error {
 317         if via := req.Header.Get("Via"); strings.Index(via, " "+viaAlias) >= 0 {
 318                 log.Printf("proxy loop detected (request has Via: %q): perhaps keepproxy is misidentified by gateway config as an external client, or its keep_services record does not have service_type=proxy?", via)
 319                 http.Error(resp, errLoopDetected.Error(), http.StatusInternalServerError)
 320                 return errLoopDetected
 321         }
 322         return nil
 323 }
 324
 325 func SetCorsHeaders(resp http.ResponseWriter) {
 326         resp.Header().Set("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, OPTIONS")
 327         resp.Header().Set("Access-Control-Allow-Origin", "*")
 328         resp.Header().Set("Access-Control-Allow-Headers", "Authorization, Content-Length, Content-Type, X-Keep-Desired-Replicas")
 329         resp.Header().Set("Access-Control-Max-Age", "86486400")
 330 }
 331
 332 type InvalidPathHandler struct{}
 333
 334 func (InvalidPathHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
 335         log.Printf("%s: %s %s unroutable", GetRemoteAddress(req), req.Method, req.URL.Path)
 336         http.Error(resp, "Bad request", http.StatusBadRequest)
 337 }
 338
 339 func (h *proxyHandler) Options(resp http.ResponseWriter, req *http.Request) {
 340         log.Printf("%s: %s %s", GetRemoteAddress(req), req.Method, req.URL.Path)
 341         SetCorsHeaders(resp)
 342 }
 343
 344 var BadAuthorizationHeader = errors.New("Missing or invalid Authorization header")
 345 var ContentLengthMismatch = errors.New("Actual length != expected content length")
 346 var MethodNotSupported = errors.New("Method not supported")
 347
 348 var removeHint, _ = regexp.Compile("\\+K@[a-z0-9]{5}(\\+|$)")
 349
 350 func (h *proxyHandler) Get(resp http.ResponseWriter, req *http.Request) {
 351         if err := h.checkLoop(resp, req); err != nil {
 352                 return
 353         }
 354         SetCorsHeaders(resp)
 355         resp.Header().Set("Via", req.Proto+" "+viaAlias)
 356
 357         locator := mux.Vars(req)["locator"]
 358         var err error
 359         var status int
 360         var expectLength, responseLength int64
 361         var proxiedURI = "-"
 362
 363         defer func() {
 364                 log.Println(GetRemoteAddress(req), req.Method, req.URL.Path, status, expectLength, responseLength, proxiedURI, err)
 365                 if status != http.StatusOK {
 366                         http.Error(resp, err.Error(), status)
 367                 }
 368         }()
 369
 370         kc := h.makeKeepClient(req)
 371
 372         var pass bool
 373         var tok string
 374         if pass, tok = CheckAuthorizationHeader(kc, h.ApiTokenCache, req); !pass {
 375                 status, err = http.StatusForbidden, BadAuthorizationHeader
 376                 return
 377         }
 378
 379         // Copy ArvadosClient struct and use the client's API token
 380         arvclient := *kc.Arvados
 381         arvclient.ApiToken = tok
 382         kc.Arvados = &arvclient
 383
 384         var reader io.ReadCloser
 385
 386         locator = removeHint.ReplaceAllString(locator, "$1")
 387
 388         switch req.Method {
 389         case "HEAD":
 390                 expectLength, proxiedURI, err = kc.Ask(locator)
 391         case "GET":
 392                 reader, expectLength, proxiedURI, err = kc.Get(locator)
 393                 if reader != nil {
 394                         defer reader.Close()
 395                 }
 396         default:
 397                 status, err = http.StatusNotImplemented, MethodNotSupported
 398                 return
 399         }
 400
 401         if expectLength == -1 {
 402                 log.Println("Warning:", GetRemoteAddress(req), req.Method, proxiedURI, "Content-Length not provided")
 403         }
 404
 405         switch respErr := err.(type) {
 406         case nil:
 407                 status = http.StatusOK
 408                 resp.Header().Set("Content-Length", fmt.Sprint(expectLength))
 409                 switch req.Method {
 410                 case "HEAD":
 411                         responseLength = 0
 412                 case "GET":
 413                         responseLength, err = io.Copy(resp, reader)
 414                         if err == nil && expectLength > -1 && responseLength != expectLength {
 415                                 err = ContentLengthMismatch
 416                         }
 417                 }
 418         case keepclient.Error:
 419                 if respErr == keepclient.BlockNotFound {
 420                         status = http.StatusNotFound
 421                 } else if respErr.Temporary() {
 422                         status = http.StatusBadGateway
 423                 } else {
 424                         status = 422
 425                 }
 426         default:
 427                 status = http.StatusInternalServerError
 428         }
 429 }
 430
 431 var LengthRequiredError = errors.New(http.StatusText(http.StatusLengthRequired))
 432 var LengthMismatchError = errors.New("Locator size hint does not match Content-Length header")
 433
 434 func (h *proxyHandler) Put(resp http.ResponseWriter, req *http.Request) {
 435         if err := h.checkLoop(resp, req); err != nil {
 436                 return
 437         }
 438         SetCorsHeaders(resp)
 439         resp.Header().Set("Via", "HTTP/1.1 "+viaAlias)
 440
 441         kc := h.makeKeepClient(req)
 442
 443         var err error
 444         var expectLength int64
 445         var status = http.StatusInternalServerError
 446         var wroteReplicas int
 447         var locatorOut string = "-"
 448
 449         defer func() {
 450                 log.Println(GetRemoteAddress(req), req.Method, req.URL.Path, status, expectLength, kc.Want_replicas, wroteReplicas, locatorOut, err)
 451                 if status != http.StatusOK {
 452                         http.Error(resp, err.Error(), status)
 453                 }
 454         }()
 455
 456         locatorIn := mux.Vars(req)["locator"]
 457
 458         _, err = fmt.Sscanf(req.Header.Get("Content-Length"), "%d", &expectLength)
 459         if err != nil || expectLength < 0 {
 460                 err = LengthRequiredError
 461                 status = http.StatusLengthRequired
 462                 return
 463         }
 464
 465         if locatorIn != "" {
 466                 var loc *keepclient.Locator
 467                 if loc, err = keepclient.MakeLocator(locatorIn); err != nil {
 468                         status = http.StatusBadRequest
 469                         return
 470                 } else if loc.Size > 0 && int64(loc.Size) != expectLength {
 471                         err = LengthMismatchError
 472                         status = http.StatusBadRequest
 473                         return
 474                 }
 475         }
 476
 477         var pass bool
 478         var tok string
 479         if pass, tok = CheckAuthorizationHeader(kc, h.ApiTokenCache, req); !pass {
 480                 err = BadAuthorizationHeader
 481                 status = http.StatusForbidden
 482                 return
 483         }
 484
 485         // Copy ArvadosClient struct and use the client's API token
 486         arvclient := *kc.Arvados
 487         arvclient.ApiToken = tok
 488         kc.Arvados = &arvclient
 489
 490         // Check if the client specified the number of replicas
 491         if req.Header.Get("X-Keep-Desired-Replicas") != "" {
 492                 var r int
 493                 _, err := fmt.Sscanf(req.Header.Get(keepclient.X_Keep_Desired_Replicas), "%d", &r)
 494                 if err == nil {
 495                         kc.Want_replicas = r
 496                 }
 497         }
 498
 499         // Now try to put the block through
 500         if locatorIn == "" {
 501                 if bytes, err := ioutil.ReadAll(req.Body); err != nil {
 502                         err = errors.New(fmt.Sprintf("Error reading request body: %s", err))
 503                         status = http.StatusInternalServerError
 504                         return
 505                 } else {
 506                         locatorOut, wroteReplicas, err = kc.PutB(bytes)
 507                 }
 508         } else {
 509                 locatorOut, wroteReplicas, err = kc.PutHR(locatorIn, req.Body, expectLength)
 510         }
 511
 512         // Tell the client how many successful PUTs we accomplished
 513         resp.Header().Set(keepclient.X_Keep_Replicas_Stored, fmt.Sprintf("%d", wroteReplicas))
 514
 515         switch err.(type) {
 516         case nil:
 517                 status = http.StatusOK
 518                 _, err = io.WriteString(resp, locatorOut)
 519
 520         case keepclient.OversizeBlockError:
 521                 // Too much data
 522                 status = http.StatusRequestEntityTooLarge
 523
 524         case keepclient.InsufficientReplicasError:
 525                 if wroteReplicas > 0 {
 526                         // At least one write is considered success.  The
 527                         // client can decide if getting less than the number of
 528                         // replications it asked for is a fatal error.
 529                         status = http.StatusOK
 530                         _, err = io.WriteString(resp, locatorOut)
 531                 } else {
 532                         status = http.StatusServiceUnavailable
 533                 }
 534
 535         default:
 536                 status = http.StatusBadGateway
 537         }
 538 }
 539
 540 // ServeHTTP implementation for IndexHandler
 541 // Supports only GET requests for /index/{prefix:[0-9a-f]{0,32}}
 542 // For each keep server found in LocalRoots:
 543 //   Invokes GetIndex using keepclient
 544 //   Expects "complete" response (terminating with blank new line)
 545 //   Aborts on any errors
 546 // Concatenates responses from all those keep servers and returns
 547 func (h *proxyHandler) Index(resp http.ResponseWriter, req *http.Request) {
 548         SetCorsHeaders(resp)
 549
 550         prefix := mux.Vars(req)["prefix"]
 551         var err error
 552         var status int
 553
 554         defer func() {
 555                 if status != http.StatusOK {
 556                         http.Error(resp, err.Error(), status)
 557                 }
 558         }()
 559
 560         kc := h.makeKeepClient(req)
 561         ok, token := CheckAuthorizationHeader(kc, h.ApiTokenCache, req)
 562         if !ok {
 563                 status, err = http.StatusForbidden, BadAuthorizationHeader
 564                 return
 565         }
 566
 567         // Copy ArvadosClient struct and use the client's API token
 568         arvclient := *kc.Arvados
 569         arvclient.ApiToken = token
 570         kc.Arvados = &arvclient
 571
 572         // Only GET method is supported
 573         if req.Method != "GET" {
 574                 status, err = http.StatusNotImplemented, MethodNotSupported
 575                 return
 576         }
 577
 578         // Get index from all LocalRoots and write to resp
 579         var reader io.Reader
 580         for uuid := range kc.LocalRoots() {
 581                 reader, err = kc.GetIndex(uuid, prefix)
 582                 if err != nil {
 583                         status = http.StatusBadGateway
 584                         return
 585                 }
 586
 587                 _, err = io.Copy(resp, reader)
 588                 if err != nil {
 589                         status = http.StatusBadGateway
 590                         return
 591                 }
 592         }
 593
 594         // Got index from all the keep servers and wrote to resp
 595         status = http.StatusOK
 596         resp.Write([]byte("\n"))
 597 }
 598
 599 func (h *proxyHandler) makeKeepClient(req *http.Request) *keepclient.KeepClient {
 600         kc := *h.KeepClient
 601         kc.HTTPClient = &proxyClient{
 602                 client: &http.Client{
 603                         Timeout:   h.timeout,
 604                         Transport: h.transport,
 605                 },
 606                 proto:     req.Proto,
 607                 requestID: req.Header.Get("X-Request-Id"),
 608         }
 609         return &kc
 610 }