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/lib/config"
  24         "git.curoverse.com/arvados.git/sdk/go/arvados"
  25         "git.curoverse.com/arvados.git/sdk/go/arvadosclient"
  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         "github.com/coreos/go-systemd/daemon"
  30         "github.com/gorilla/mux"
  31         log "github.com/sirupsen/logrus"
  32         "gopkg.in/yaml.v2"
  33 )
  34
  35 var version = "dev"
  36
  37 var (
  38         listener net.Listener
  39         router   http.Handler
  40 )
  41
  42 const rfc3339NanoFixed = "2006-01-02T15:04:05.000000000Z07:00"
  43
  44 func configure(logger log.FieldLogger, args []string) *arvados.Cluster {
  45         flags := flag.NewFlagSet(args[0], flag.ExitOnError)
  46         flags.Usage = usage
  47
  48         dumpConfig := flags.Bool("dump-config", false, "write current configuration to stdout and exit")
  49         getVersion := flags.Bool("version", false, "Print version information and exit.")
  50
  51         loader := config.NewLoader(os.Stdin, logger)
  52         loader.SetupFlags(flags)
  53
  54         args = loader.MungeLegacyConfigArgs(logger, args[1:], "-legacy-keepproxy-config")
  55         flags.Parse(args)
  56
  57         // Print version information if requested
  58         if *getVersion {
  59                 fmt.Printf("keepproxy %s\n", version)
  60                 return nil
  61         }
  62
  63         cfg, err := loader.Load()
  64         if err != nil {
  65                 log.Fatal(err)
  66         }
  67
  68         cluster, err := cfg.GetCluster("")
  69         if err != nil {
  70                 log.Fatal(err)
  71         }
  72
  73         if *dumpConfig {
  74                 out, err := yaml.Marshal(cfg)
  75                 if err != nil {
  76                         log.Fatal(err)
  77                 }
  78                 _, err = os.Stdout.Write(out)
  79                 if err != nil {
  80                         log.Fatal(err)
  81                 }
  82                 return nil
  83         }
  84         return cluster
  85 }
  86
  87 func main() {
  88         logger := log.New()
  89         logger.Formatter = &log.JSONFormatter{
  90                 TimestampFormat: rfc3339NanoFixed,
  91         }
  92
  93         cluster := configure(logger, os.Args)
  94         if cluster == nil {
  95                 return
  96         }
  97
  98         log.Printf("keepproxy %s started", version)
  99
 100         client, err := arvados.NewClientFromConfig(cluster)
 101         if err != nil {
 102                 log.Fatal(err)
 103         }
 104         client.AuthToken = cluster.SystemRootToken
 105
 106         arv, err := arvadosclient.New(client)
 107         if err != nil {
 108                 log.Fatalf("Error setting up arvados client %s", err.Error())
 109         }
 110
 111         if cluster.SystemLogs.LogLevel == "debug" {
 112                 keepclient.DebugPrintf = log.Printf
 113         }
 114         kc, err := keepclient.MakeKeepClient(arv)
 115         if err != nil {
 116                 log.Fatalf("Error setting up keep client %s", err.Error())
 117         }
 118         keepclient.RefreshServiceDiscoveryOnSIGHUP()
 119
 120         if cluster.Collections.DefaultReplication > 0 {
 121                 kc.Want_replicas = cluster.Collections.DefaultReplication
 122         }
 123
 124         var listen arvados.URL
 125         for listen = range cluster.Services.Keepproxy.InternalURLs {
 126                 break
 127         }
 128         listener, err := net.Listen("tcp", listen.Host)
 129         if err != nil {
 130                 log.Fatalf("listen(%s): %s", listen.Host, err)
 131         }
 132
 133         if _, err := daemon.SdNotify(false, "READY=1"); err != nil {
 134                 log.Printf("Error notifying init daemon: %v", err)
 135         }
 136         log.Println("Listening at", listener.Addr())
 137
 138         // Shut down the server gracefully (by closing the listener)
 139         // if SIGTERM is received.
 140         term := make(chan os.Signal, 1)
 141         go func(sig <-chan os.Signal) {
 142                 s := <-sig
 143                 log.Println("caught signal:", s)
 144                 listener.Close()
 145         }(term)
 146         signal.Notify(term, syscall.SIGTERM)
 147         signal.Notify(term, syscall.SIGINT)
 148
 149         // Start serving requests.
 150         router = MakeRESTRouter(kc, time.Duration(cluster.API.KeepServiceRequestTimeout), cluster.SystemRootToken)
 151         http.Serve(listener, httpserver.AddRequestIDs(httpserver.LogRequests(router)))
 152
 153         log.Println("shutting down")
 154 }
 155
 156 type ApiTokenCache struct {
 157         tokens     map[string]int64
 158         lock       sync.Mutex
 159         expireTime int64
 160 }
 161
 162 // Cache the token and set an expire time.  If we already have an expire time
 163 // on the token, it is not updated.
 164 func (this *ApiTokenCache) RememberToken(token string) {
 165         this.lock.Lock()
 166         defer this.lock.Unlock()
 167
 168         now := time.Now().Unix()
 169         if this.tokens[token] == 0 {
 170                 this.tokens[token] = now + this.expireTime
 171         }
 172 }
 173
 174 // Check if the cached token is known and still believed to be valid.
 175 func (this *ApiTokenCache) RecallToken(token string) bool {
 176         this.lock.Lock()
 177         defer this.lock.Unlock()
 178
 179         now := time.Now().Unix()
 180         if this.tokens[token] == 0 {
 181                 // Unknown token
 182                 return false
 183         } else if now < this.tokens[token] {
 184                 // Token is known and still valid
 185                 return true
 186         } else {
 187                 // Token is expired
 188                 this.tokens[token] = 0
 189                 return false
 190         }
 191 }
 192
 193 func GetRemoteAddress(req *http.Request) string {
 194         if xff := req.Header.Get("X-Forwarded-For"); xff != "" {
 195                 return xff + "," + req.RemoteAddr
 196         }
 197         return req.RemoteAddr
 198 }
 199
 200 func CheckAuthorizationHeader(kc *keepclient.KeepClient, cache *ApiTokenCache, req *http.Request) (pass bool, tok string) {
 201         parts := strings.SplitN(req.Header.Get("Authorization"), " ", 2)
 202         if len(parts) < 2 || !(parts[0] == "OAuth2" || parts[0] == "Bearer") || len(parts[1]) == 0 {
 203                 return false, ""
 204         }
 205         tok = parts[1]
 206
 207         // Tokens are validated differently depending on what kind of
 208         // operation is being performed. For example, tokens in
 209         // collection-sharing links permit GET requests, but not
 210         // PUT requests.
 211         var op string
 212         if req.Method == "GET" || req.Method == "HEAD" {
 213                 op = "read"
 214         } else {
 215                 op = "write"
 216         }
 217
 218         if cache.RecallToken(op + ":" + tok) {
 219                 // Valid in the cache, short circuit
 220                 return true, tok
 221         }
 222
 223         var err error
 224         arv := *kc.Arvados
 225         arv.ApiToken = tok
 226         arv.RequestID = req.Header.Get("X-Request-Id")
 227         if op == "read" {
 228                 err = arv.Call("HEAD", "keep_services", "", "accessible", nil, nil)
 229         } else {
 230                 err = arv.Call("HEAD", "users", "", "current", nil, nil)
 231         }
 232         if err != nil {
 233                 log.Printf("%s: CheckAuthorizationHeader error: %v", GetRemoteAddress(req), err)
 234                 return false, ""
 235         }
 236
 237         // Success!  Update cache
 238         cache.RememberToken(op + ":" + tok)
 239
 240         return true, tok
 241 }
 242
 243 // We need to make a private copy of the default http transport early
 244 // in initialization, then make copies of our private copy later. It
 245 // won't be safe to copy http.DefaultTransport itself later, because
 246 // its private mutexes might have already been used. (Without this,
 247 // the test suite sometimes panics "concurrent map writes" in
 248 // net/http.(*Transport).removeIdleConnLocked().)
 249 var defaultTransport = *(http.DefaultTransport.(*http.Transport))
 250
 251 type proxyHandler struct {
 252         http.Handler
 253         *keepclient.KeepClient
 254         *ApiTokenCache
 255         timeout   time.Duration
 256         transport *http.Transport
 257 }
 258
 259 // MakeRESTRouter returns an http.Handler that passes GET and PUT
 260 // requests to the appropriate handlers.
 261 func MakeRESTRouter(kc *keepclient.KeepClient, timeout time.Duration, mgmtToken string) http.Handler {
 262         rest := mux.NewRouter()
 263
 264         transport := defaultTransport
 265         transport.DialContext = (&net.Dialer{
 266                 Timeout:   keepclient.DefaultConnectTimeout,
 267                 KeepAlive: keepclient.DefaultKeepAlive,
 268                 DualStack: true,
 269         }).DialContext
 270         transport.TLSClientConfig = arvadosclient.MakeTLSConfig(kc.Arvados.ApiInsecure)
 271         transport.TLSHandshakeTimeout = keepclient.DefaultTLSHandshakeTimeout
 272
 273         h := &proxyHandler{
 274                 Handler:    rest,
 275                 KeepClient: kc,
 276                 timeout:    timeout,
 277                 transport:  &transport,
 278                 ApiTokenCache: &ApiTokenCache{
 279                         tokens:     make(map[string]int64),
 280                         expireTime: 300,
 281                 },
 282         }
 283
 284         rest.HandleFunc(`/{locator:[0-9a-f]{32}\+.*}`, h.Get).Methods("GET", "HEAD")
 285         rest.HandleFunc(`/{locator:[0-9a-f]{32}}`, h.Get).Methods("GET", "HEAD")
 286
 287         // List all blocks
 288         rest.HandleFunc(`/index`, h.Index).Methods("GET")
 289
 290         // List blocks whose hash has the given prefix
 291         rest.HandleFunc(`/index/{prefix:[0-9a-f]{0,32}}`, h.Index).Methods("GET")
 292
 293         rest.HandleFunc(`/{locator:[0-9a-f]{32}\+.*}`, h.Put).Methods("PUT")
 294         rest.HandleFunc(`/{locator:[0-9a-f]{32}}`, h.Put).Methods("PUT")
 295         rest.HandleFunc(`/`, h.Put).Methods("POST")
 296         rest.HandleFunc(`/{any}`, h.Options).Methods("OPTIONS")
 297         rest.HandleFunc(`/`, h.Options).Methods("OPTIONS")
 298
 299         rest.Handle("/_health/{check}", &health.Handler{
 300                 Token:  mgmtToken,
 301                 Prefix: "/_health/",
 302         }).Methods("GET")
 303
 304         rest.NotFoundHandler = InvalidPathHandler{}
 305         return h
 306 }
 307
 308 var errLoopDetected = errors.New("loop detected")
 309
 310 func (*proxyHandler) checkLoop(resp http.ResponseWriter, req *http.Request) error {
 311         if via := req.Header.Get("Via"); strings.Index(via, " "+viaAlias) >= 0 {
 312                 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)
 313                 http.Error(resp, errLoopDetected.Error(), http.StatusInternalServerError)
 314                 return errLoopDetected
 315         }
 316         return nil
 317 }
 318
 319 func SetCorsHeaders(resp http.ResponseWriter) {
 320         resp.Header().Set("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, OPTIONS")
 321         resp.Header().Set("Access-Control-Allow-Origin", "*")
 322         resp.Header().Set("Access-Control-Allow-Headers", "Authorization, Content-Length, Content-Type, X-Keep-Desired-Replicas")
 323         resp.Header().Set("Access-Control-Max-Age", "86486400")
 324 }
 325
 326 type InvalidPathHandler struct{}
 327
 328 func (InvalidPathHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
 329         log.Printf("%s: %s %s unroutable", GetRemoteAddress(req), req.Method, req.URL.Path)
 330         http.Error(resp, "Bad request", http.StatusBadRequest)
 331 }
 332
 333 func (h *proxyHandler) Options(resp http.ResponseWriter, req *http.Request) {
 334         log.Printf("%s: %s %s", GetRemoteAddress(req), req.Method, req.URL.Path)
 335         SetCorsHeaders(resp)
 336 }
 337
 338 var BadAuthorizationHeader = errors.New("Missing or invalid Authorization header")
 339 var ContentLengthMismatch = errors.New("Actual length != expected content length")
 340 var MethodNotSupported = errors.New("Method not supported")
 341
 342 var removeHint, _ = regexp.Compile("\\+K@[a-z0-9]{5}(\\+|$)")
 343
 344 func (h *proxyHandler) Get(resp http.ResponseWriter, req *http.Request) {
 345         if err := h.checkLoop(resp, req); err != nil {
 346                 return
 347         }
 348         SetCorsHeaders(resp)
 349         resp.Header().Set("Via", req.Proto+" "+viaAlias)
 350
 351         locator := mux.Vars(req)["locator"]
 352         var err error
 353         var status int
 354         var expectLength, responseLength int64
 355         var proxiedURI = "-"
 356
 357         defer func() {
 358                 log.Println(GetRemoteAddress(req), req.Method, req.URL.Path, status, expectLength, responseLength, proxiedURI, err)
 359                 if status != http.StatusOK {
 360                         http.Error(resp, err.Error(), status)
 361                 }
 362         }()
 363
 364         kc := h.makeKeepClient(req)
 365
 366         var pass bool
 367         var tok string
 368         if pass, tok = CheckAuthorizationHeader(kc, h.ApiTokenCache, req); !pass {
 369                 status, err = http.StatusForbidden, BadAuthorizationHeader
 370                 return
 371         }
 372
 373         // Copy ArvadosClient struct and use the client's API token
 374         arvclient := *kc.Arvados
 375         arvclient.ApiToken = tok
 376         kc.Arvados = &arvclient
 377
 378         var reader io.ReadCloser
 379
 380         locator = removeHint.ReplaceAllString(locator, "$1")
 381
 382         switch req.Method {
 383         case "HEAD":
 384                 expectLength, proxiedURI, err = kc.Ask(locator)
 385         case "GET":
 386                 reader, expectLength, proxiedURI, err = kc.Get(locator)
 387                 if reader != nil {
 388                         defer reader.Close()
 389                 }
 390         default:
 391                 status, err = http.StatusNotImplemented, MethodNotSupported
 392                 return
 393         }
 394
 395         if expectLength == -1 {
 396                 log.Println("Warning:", GetRemoteAddress(req), req.Method, proxiedURI, "Content-Length not provided")
 397         }
 398
 399         switch respErr := err.(type) {
 400         case nil:
 401                 status = http.StatusOK
 402                 resp.Header().Set("Content-Length", fmt.Sprint(expectLength))
 403                 switch req.Method {
 404                 case "HEAD":
 405                         responseLength = 0
 406                 case "GET":
 407                         responseLength, err = io.Copy(resp, reader)
 408                         if err == nil && expectLength > -1 && responseLength != expectLength {
 409                                 err = ContentLengthMismatch
 410                         }
 411                 }
 412         case keepclient.Error:
 413                 if respErr == keepclient.BlockNotFound {
 414                         status = http.StatusNotFound
 415                 } else if respErr.Temporary() {
 416                         status = http.StatusBadGateway
 417                 } else {
 418                         status = 422
 419                 }
 420         default:
 421                 status = http.StatusInternalServerError
 422         }
 423 }
 424
 425 var LengthRequiredError = errors.New(http.StatusText(http.StatusLengthRequired))
 426 var LengthMismatchError = errors.New("Locator size hint does not match Content-Length header")
 427
 428 func (h *proxyHandler) Put(resp http.ResponseWriter, req *http.Request) {
 429         if err := h.checkLoop(resp, req); err != nil {
 430                 return
 431         }
 432         SetCorsHeaders(resp)
 433         resp.Header().Set("Via", "HTTP/1.1 "+viaAlias)
 434
 435         kc := h.makeKeepClient(req)
 436
 437         var err error
 438         var expectLength int64
 439         var status = http.StatusInternalServerError
 440         var wroteReplicas int
 441         var locatorOut string = "-"
 442
 443         defer func() {
 444                 log.Println(GetRemoteAddress(req), req.Method, req.URL.Path, status, expectLength, kc.Want_replicas, wroteReplicas, locatorOut, err)
 445                 if status != http.StatusOK {
 446                         http.Error(resp, err.Error(), status)
 447                 }
 448         }()
 449
 450         locatorIn := mux.Vars(req)["locator"]
 451
 452         // Check if the client specified storage classes
 453         if req.Header.Get("X-Keep-Storage-Classes") != "" {
 454                 var scl []string
 455                 for _, sc := range strings.Split(req.Header.Get("X-Keep-Storage-Classes"), ",") {
 456                         scl = append(scl, strings.Trim(sc, " "))
 457                 }
 458                 kc.StorageClasses = scl
 459         }
 460
 461         _, err = fmt.Sscanf(req.Header.Get("Content-Length"), "%d", &expectLength)
 462         if err != nil || expectLength < 0 {
 463                 err = LengthRequiredError
 464                 status = http.StatusLengthRequired
 465                 return
 466         }
 467
 468         if locatorIn != "" {
 469                 var loc *keepclient.Locator
 470                 if loc, err = keepclient.MakeLocator(locatorIn); err != nil {
 471                         status = http.StatusBadRequest
 472                         return
 473                 } else if loc.Size > 0 && int64(loc.Size) != expectLength {
 474                         err = LengthMismatchError
 475                         status = http.StatusBadRequest
 476                         return
 477                 }
 478         }
 479
 480         var pass bool
 481         var tok string
 482         if pass, tok = CheckAuthorizationHeader(kc, h.ApiTokenCache, req); !pass {
 483                 err = BadAuthorizationHeader
 484                 status = http.StatusForbidden
 485                 return
 486         }
 487
 488         // Copy ArvadosClient struct and use the client's API token
 489         arvclient := *kc.Arvados
 490         arvclient.ApiToken = tok
 491         kc.Arvados = &arvclient
 492
 493         // Check if the client specified the number of replicas
 494         if req.Header.Get("X-Keep-Desired-Replicas") != "" {
 495                 var r int
 496                 _, err := fmt.Sscanf(req.Header.Get(keepclient.X_Keep_Desired_Replicas), "%d", &r)
 497                 if err == nil {
 498                         kc.Want_replicas = r
 499                 }
 500         }
 501
 502         // Now try to put the block through
 503         if locatorIn == "" {
 504                 bytes, err2 := ioutil.ReadAll(req.Body)
 505                 if err2 != nil {
 506                         err = fmt.Errorf("Error reading request body: %s", err2)
 507                         status = http.StatusInternalServerError
 508                         return
 509                 }
 510                 locatorOut, wroteReplicas, err = kc.PutB(bytes)
 511         } else {
 512                 locatorOut, wroteReplicas, err = kc.PutHR(locatorIn, req.Body, expectLength)
 513         }
 514
 515         // Tell the client how many successful PUTs we accomplished
 516         resp.Header().Set(keepclient.X_Keep_Replicas_Stored, fmt.Sprintf("%d", wroteReplicas))
 517
 518         switch err.(type) {
 519         case nil:
 520                 status = http.StatusOK
 521                 _, err = io.WriteString(resp, locatorOut)
 522
 523         case keepclient.OversizeBlockError:
 524                 // Too much data
 525                 status = http.StatusRequestEntityTooLarge
 526
 527         case keepclient.InsufficientReplicasError:
 528                 if wroteReplicas > 0 {
 529                         // At least one write is considered success.  The
 530                         // client can decide if getting less than the number of
 531                         // replications it asked for is a fatal error.
 532                         status = http.StatusOK
 533                         _, err = io.WriteString(resp, locatorOut)
 534                 } else {
 535                         status = http.StatusServiceUnavailable
 536                 }
 537
 538         default:
 539                 status = http.StatusBadGateway
 540         }
 541 }
 542
 543 // ServeHTTP implementation for IndexHandler
 544 // Supports only GET requests for /index/{prefix:[0-9a-f]{0,32}}
 545 // For each keep server found in LocalRoots:
 546 //   Invokes GetIndex using keepclient
 547 //   Expects "complete" response (terminating with blank new line)
 548 //   Aborts on any errors
 549 // Concatenates responses from all those keep servers and returns
 550 func (h *proxyHandler) Index(resp http.ResponseWriter, req *http.Request) {
 551         SetCorsHeaders(resp)
 552
 553         prefix := mux.Vars(req)["prefix"]
 554         var err error
 555         var status int
 556
 557         defer func() {
 558                 if status != http.StatusOK {
 559                         http.Error(resp, err.Error(), status)
 560                 }
 561         }()
 562
 563         kc := h.makeKeepClient(req)
 564         ok, token := CheckAuthorizationHeader(kc, h.ApiTokenCache, req)
 565         if !ok {
 566                 status, err = http.StatusForbidden, BadAuthorizationHeader
 567                 return
 568         }
 569
 570         // Copy ArvadosClient struct and use the client's API token
 571         arvclient := *kc.Arvados
 572         arvclient.ApiToken = token
 573         kc.Arvados = &arvclient
 574
 575         // Only GET method is supported
 576         if req.Method != "GET" {
 577                 status, err = http.StatusNotImplemented, MethodNotSupported
 578                 return
 579         }
 580
 581         // Get index from all LocalRoots and write to resp
 582         var reader io.Reader
 583         for uuid := range kc.LocalRoots() {
 584                 reader, err = kc.GetIndex(uuid, prefix)
 585                 if err != nil {
 586                         status = http.StatusBadGateway
 587                         return
 588                 }
 589
 590                 _, err = io.Copy(resp, reader)
 591                 if err != nil {
 592                         status = http.StatusBadGateway
 593                         return
 594                 }
 595         }
 596
 597         // Got index from all the keep servers and wrote to resp
 598         status = http.StatusOK
 599         resp.Write([]byte("\n"))
 600 }
 601
 602 func (h *proxyHandler) makeKeepClient(req *http.Request) *keepclient.KeepClient {
 603         kc := *h.KeepClient
 604         kc.RequestID = req.Header.Get("X-Request-Id")
 605         kc.HTTPClient = &proxyClient{
 606                 client: &http.Client{
 607                         Timeout:   h.timeout,
 608                         Transport: h.transport,
 609                 },
 610                 proto: req.Proto,
 611         }
 612         return &kc
 613 }