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/ghodss/yaml"
  31         "github.com/gorilla/mux"
  32         log "github.com/sirupsen/logrus"
  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, error) {
  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, nil
  61         }
  62
  63         cfg, err := loader.Load()
  64         if err != nil {
  65                 return nil, err
  66         }
  67         cluster, err := cfg.GetCluster("")
  68         if err != nil {
  69                 return nil, err
  70         }
  71
  72         if *dumpConfig {
  73                 out, err := yaml.Marshal(cfg)
  74                 if err != nil {
  75                         return nil, err
  76                 }
  77                 if _, err := os.Stdout.Write(out); err != nil {
  78                         return nil, err
  79                 }
  80                 return nil, nil
  81         }
  82         return cluster, nil
  83 }
  84
  85 func main() {
  86         logger := log.New()
  87         logger.Formatter = &log.JSONFormatter{
  88                 TimestampFormat: rfc3339NanoFixed,
  89         }
  90
  91         cluster, err := configure(logger, os.Args)
  92         if err != nil {
  93                 log.Fatal(err)
  94         }
  95         if cluster == nil {
  96                 return
  97         }
  98
  99         log.Printf("keepproxy %s started", version)
 100
 101         if err := run(logger, cluster); err != nil {
 102                 log.Fatal(err)
 103         }
 104
 105         log.Println("shutting down")
 106 }
 107
 108 func run(logger log.FieldLogger, cluster *arvados.Cluster) error {
 109         client, err := arvados.NewClientFromConfig(cluster)
 110         if err != nil {
 111                 return err
 112         }
 113         client.AuthToken = cluster.SystemRootToken
 114
 115         arv, err := arvadosclient.New(client)
 116         if err != nil {
 117                 return fmt.Errorf("Error setting up arvados client %v", err)
 118         }
 119
 120         if cluster.SystemLogs.LogLevel == "debug" {
 121                 keepclient.DebugPrintf = log.Printf
 122         }
 123         kc, err := keepclient.MakeKeepClient(arv)
 124         if err != nil {
 125                 return fmt.Errorf("Error setting up keep client %v", err)
 126         }
 127         keepclient.RefreshServiceDiscoveryOnSIGHUP()
 128
 129         if cluster.Collections.DefaultReplication > 0 {
 130                 kc.Want_replicas = cluster.Collections.DefaultReplication
 131         }
 132
 133         var listen arvados.URL
 134         for listen = range cluster.Services.Keepproxy.InternalURLs {
 135                 break
 136         }
 137
 138         var lErr error
 139         listener, lErr = net.Listen("tcp", listen.Host)
 140         if lErr != nil {
 141                 return fmt.Errorf("listen(%s): %v", listen.Host, lErr)
 142         }
 143
 144         if _, err := daemon.SdNotify(false, "READY=1"); err != nil {
 145                 log.Printf("Error notifying init daemon: %v", err)
 146         }
 147         log.Println("listening at", listener.Addr())
 148
 149         // Shut down the server gracefully (by closing the listener)
 150         // if SIGTERM is received.
 151         term := make(chan os.Signal, 1)
 152         go func(sig <-chan os.Signal) {
 153                 s := <-sig
 154                 log.Println("caught signal:", s)
 155                 listener.Close()
 156         }(term)
 157         signal.Notify(term, syscall.SIGTERM)
 158         signal.Notify(term, syscall.SIGINT)
 159
 160         // Start serving requests.
 161         router = MakeRESTRouter(kc, time.Duration(cluster.API.KeepServiceRequestTimeout), cluster.SystemRootToken)
 162         return http.Serve(listener, httpserver.AddRequestIDs(httpserver.LogRequests(router)))
 163 }
 164
 165 type ApiTokenCache struct {
 166         tokens     map[string]int64
 167         lock       sync.Mutex
 168         expireTime int64
 169 }
 170
 171 // Cache the token and set an expire time.  If we already have an expire time
 172 // on the token, it is not updated.
 173 func (this *ApiTokenCache) RememberToken(token string) {
 174         this.lock.Lock()
 175         defer this.lock.Unlock()
 176
 177         now := time.Now().Unix()
 178         if this.tokens[token] == 0 {
 179                 this.tokens[token] = now + this.expireTime
 180         }
 181 }
 182
 183 // Check if the cached token is known and still believed to be valid.
 184 func (this *ApiTokenCache) RecallToken(token string) bool {
 185         this.lock.Lock()
 186         defer this.lock.Unlock()
 187
 188         now := time.Now().Unix()
 189         if this.tokens[token] == 0 {
 190                 // Unknown token
 191                 return false
 192         } else if now < this.tokens[token] {
 193                 // Token is known and still valid
 194                 return true
 195         } else {
 196                 // Token is expired
 197                 this.tokens[token] = 0
 198                 return false
 199         }
 200 }
 201
 202 func GetRemoteAddress(req *http.Request) string {
 203         if xff := req.Header.Get("X-Forwarded-For"); xff != "" {
 204                 return xff + "," + req.RemoteAddr
 205         }
 206         return req.RemoteAddr
 207 }
 208
 209 func CheckAuthorizationHeader(kc *keepclient.KeepClient, cache *ApiTokenCache, req *http.Request) (pass bool, tok string) {
 210         parts := strings.SplitN(req.Header.Get("Authorization"), " ", 2)
 211         if len(parts) < 2 || !(parts[0] == "OAuth2" || parts[0] == "Bearer") || len(parts[1]) == 0 {
 212                 return false, ""
 213         }
 214         tok = parts[1]
 215
 216         // Tokens are validated differently depending on what kind of
 217         // operation is being performed. For example, tokens in
 218         // collection-sharing links permit GET requests, but not
 219         // PUT requests.
 220         var op string
 221         if req.Method == "GET" || req.Method == "HEAD" {
 222                 op = "read"
 223         } else {
 224                 op = "write"
 225         }
 226
 227         if cache.RecallToken(op + ":" + tok) {
 228                 // Valid in the cache, short circuit
 229                 return true, tok
 230         }
 231
 232         var err error
 233         arv := *kc.Arvados
 234         arv.ApiToken = tok
 235         arv.RequestID = req.Header.Get("X-Request-Id")
 236         if op == "read" {
 237                 err = arv.Call("HEAD", "keep_services", "", "accessible", nil, nil)
 238         } else {
 239                 err = arv.Call("HEAD", "users", "", "current", nil, nil)
 240         }
 241         if err != nil {
 242                 log.Printf("%s: CheckAuthorizationHeader error: %v", GetRemoteAddress(req), err)
 243                 return false, ""
 244         }
 245
 246         // Success!  Update cache
 247         cache.RememberToken(op + ":" + tok)
 248
 249         return true, tok
 250 }
 251
 252 // We need to make a private copy of the default http transport early
 253 // in initialization, then make copies of our private copy later. It
 254 // won't be safe to copy http.DefaultTransport itself later, because
 255 // its private mutexes might have already been used. (Without this,
 256 // the test suite sometimes panics "concurrent map writes" in
 257 // net/http.(*Transport).removeIdleConnLocked().)
 258 var defaultTransport = *(http.DefaultTransport.(*http.Transport))
 259
 260 type proxyHandler struct {
 261         http.Handler
 262         *keepclient.KeepClient
 263         *ApiTokenCache
 264         timeout   time.Duration
 265         transport *http.Transport
 266 }
 267
 268 // MakeRESTRouter returns an http.Handler that passes GET and PUT
 269 // requests to the appropriate handlers.
 270 func MakeRESTRouter(kc *keepclient.KeepClient, timeout time.Duration, mgmtToken string) http.Handler {
 271         rest := mux.NewRouter()
 272
 273         transport := defaultTransport
 274         transport.DialContext = (&net.Dialer{
 275                 Timeout:   keepclient.DefaultConnectTimeout,
 276                 KeepAlive: keepclient.DefaultKeepAlive,
 277                 DualStack: true,
 278         }).DialContext
 279         transport.TLSClientConfig = arvadosclient.MakeTLSConfig(kc.Arvados.ApiInsecure)
 280         transport.TLSHandshakeTimeout = keepclient.DefaultTLSHandshakeTimeout
 281
 282         h := &proxyHandler{
 283                 Handler:    rest,
 284                 KeepClient: kc,
 285                 timeout:    timeout,
 286                 transport:  &transport,
 287                 ApiTokenCache: &ApiTokenCache{
 288                         tokens:     make(map[string]int64),
 289                         expireTime: 300,
 290                 },
 291         }
 292
 293         rest.HandleFunc(`/{locator:[0-9a-f]{32}\+.*}`, h.Get).Methods("GET", "HEAD")
 294         rest.HandleFunc(`/{locator:[0-9a-f]{32}}`, h.Get).Methods("GET", "HEAD")
 295
 296         // List all blocks
 297         rest.HandleFunc(`/index`, h.Index).Methods("GET")
 298
 299         // List blocks whose hash has the given prefix
 300         rest.HandleFunc(`/index/{prefix:[0-9a-f]{0,32}}`, h.Index).Methods("GET")
 301
 302         rest.HandleFunc(`/{locator:[0-9a-f]{32}\+.*}`, h.Put).Methods("PUT")
 303         rest.HandleFunc(`/{locator:[0-9a-f]{32}}`, h.Put).Methods("PUT")
 304         rest.HandleFunc(`/`, h.Put).Methods("POST")
 305         rest.HandleFunc(`/{any}`, h.Options).Methods("OPTIONS")
 306         rest.HandleFunc(`/`, h.Options).Methods("OPTIONS")
 307
 308         rest.Handle("/_health/{check}", &health.Handler{
 309                 Token:  mgmtToken,
 310                 Prefix: "/_health/",
 311         }).Methods("GET")
 312
 313         rest.NotFoundHandler = InvalidPathHandler{}
 314         return h
 315 }
 316
 317 var errLoopDetected = errors.New("loop detected")
 318
 319 func (*proxyHandler) checkLoop(resp http.ResponseWriter, req *http.Request) error {
 320         if via := req.Header.Get("Via"); strings.Index(via, " "+viaAlias) >= 0 {
 321                 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)
 322                 http.Error(resp, errLoopDetected.Error(), http.StatusInternalServerError)
 323                 return errLoopDetected
 324         }
 325         return nil
 326 }
 327
 328 func SetCorsHeaders(resp http.ResponseWriter) {
 329         resp.Header().Set("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, OPTIONS")
 330         resp.Header().Set("Access-Control-Allow-Origin", "*")
 331         resp.Header().Set("Access-Control-Allow-Headers", "Authorization, Content-Length, Content-Type, X-Keep-Desired-Replicas")
 332         resp.Header().Set("Access-Control-Max-Age", "86486400")
 333 }
 334
 335 type InvalidPathHandler struct{}
 336
 337 func (InvalidPathHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
 338         log.Printf("%s: %s %s unroutable", GetRemoteAddress(req), req.Method, req.URL.Path)
 339         http.Error(resp, "Bad request", http.StatusBadRequest)
 340 }
 341
 342 func (h *proxyHandler) Options(resp http.ResponseWriter, req *http.Request) {
 343         log.Printf("%s: %s %s", GetRemoteAddress(req), req.Method, req.URL.Path)
 344         SetCorsHeaders(resp)
 345 }
 346
 347 var BadAuthorizationHeader = errors.New("Missing or invalid Authorization header")
 348 var ContentLengthMismatch = errors.New("Actual length != expected content length")
 349 var MethodNotSupported = errors.New("Method not supported")
 350
 351 var removeHint, _ = regexp.Compile("\\+K@[a-z0-9]{5}(\\+|$)")
 352
 353 func (h *proxyHandler) Get(resp http.ResponseWriter, req *http.Request) {
 354         if err := h.checkLoop(resp, req); err != nil {
 355                 return
 356         }
 357         SetCorsHeaders(resp)
 358         resp.Header().Set("Via", req.Proto+" "+viaAlias)
 359
 360         locator := mux.Vars(req)["locator"]
 361         var err error
 362         var status int
 363         var expectLength, responseLength int64
 364         var proxiedURI = "-"
 365
 366         defer func() {
 367                 log.Println(GetRemoteAddress(req), req.Method, req.URL.Path, status, expectLength, responseLength, proxiedURI, err)
 368                 if status != http.StatusOK {
 369                         http.Error(resp, err.Error(), status)
 370                 }
 371         }()
 372
 373         kc := h.makeKeepClient(req)
 374
 375         var pass bool
 376         var tok string
 377         if pass, tok = CheckAuthorizationHeader(kc, h.ApiTokenCache, req); !pass {
 378                 status, err = http.StatusForbidden, BadAuthorizationHeader
 379                 return
 380         }
 381
 382         // Copy ArvadosClient struct and use the client's API token
 383         arvclient := *kc.Arvados
 384         arvclient.ApiToken = tok
 385         kc.Arvados = &arvclient
 386
 387         var reader io.ReadCloser
 388
 389         locator = removeHint.ReplaceAllString(locator, "$1")
 390
 391         switch req.Method {
 392         case "HEAD":
 393                 expectLength, proxiedURI, err = kc.Ask(locator)
 394         case "GET":
 395                 reader, expectLength, proxiedURI, err = kc.Get(locator)
 396                 if reader != nil {
 397                         defer reader.Close()
 398                 }
 399         default:
 400                 status, err = http.StatusNotImplemented, MethodNotSupported
 401                 return
 402         }
 403
 404         if expectLength == -1 {
 405                 log.Println("Warning:", GetRemoteAddress(req), req.Method, proxiedURI, "Content-Length not provided")
 406         }
 407
 408         switch respErr := err.(type) {
 409         case nil:
 410                 status = http.StatusOK
 411                 resp.Header().Set("Content-Length", fmt.Sprint(expectLength))
 412                 switch req.Method {
 413                 case "HEAD":
 414                         responseLength = 0
 415                 case "GET":
 416                         responseLength, err = io.Copy(resp, reader)
 417                         if err == nil && expectLength > -1 && responseLength != expectLength {
 418                                 err = ContentLengthMismatch
 419                         }
 420                 }
 421         case keepclient.Error:
 422                 if respErr == keepclient.BlockNotFound {
 423                         status = http.StatusNotFound
 424                 } else if respErr.Temporary() {
 425                         status = http.StatusBadGateway
 426                 } else {
 427                         status = 422
 428                 }
 429         default:
 430                 status = http.StatusInternalServerError
 431         }
 432 }
 433
 434 var LengthRequiredError = errors.New(http.StatusText(http.StatusLengthRequired))
 435 var LengthMismatchError = errors.New("Locator size hint does not match Content-Length header")
 436
 437 func (h *proxyHandler) Put(resp http.ResponseWriter, req *http.Request) {
 438         if err := h.checkLoop(resp, req); err != nil {
 439                 return
 440         }
 441         SetCorsHeaders(resp)
 442         resp.Header().Set("Via", "HTTP/1.1 "+viaAlias)
 443
 444         kc := h.makeKeepClient(req)
 445
 446         var err error
 447         var expectLength int64
 448         var status = http.StatusInternalServerError
 449         var wroteReplicas int
 450         var locatorOut string = "-"
 451
 452         defer func() {
 453                 log.Println(GetRemoteAddress(req), req.Method, req.URL.Path, status, expectLength, kc.Want_replicas, wroteReplicas, locatorOut, err)
 454                 if status != http.StatusOK {
 455                         http.Error(resp, err.Error(), status)
 456                 }
 457         }()
 458
 459         locatorIn := mux.Vars(req)["locator"]
 460
 461         // Check if the client specified storage classes
 462         if req.Header.Get("X-Keep-Storage-Classes") != "" {
 463                 var scl []string
 464                 for _, sc := range strings.Split(req.Header.Get("X-Keep-Storage-Classes"), ",") {
 465                         scl = append(scl, strings.Trim(sc, " "))
 466                 }
 467                 kc.StorageClasses = scl
 468         }
 469
 470         _, err = fmt.Sscanf(req.Header.Get("Content-Length"), "%d", &expectLength)
 471         if err != nil || expectLength < 0 {
 472                 err = LengthRequiredError
 473                 status = http.StatusLengthRequired
 474                 return
 475         }
 476
 477         if locatorIn != "" {
 478                 var loc *keepclient.Locator
 479                 if loc, err = keepclient.MakeLocator(locatorIn); err != nil {
 480                         status = http.StatusBadRequest
 481                         return
 482                 } else if loc.Size > 0 && int64(loc.Size) != expectLength {
 483                         err = LengthMismatchError
 484                         status = http.StatusBadRequest
 485                         return
 486                 }
 487         }
 488
 489         var pass bool
 490         var tok string
 491         if pass, tok = CheckAuthorizationHeader(kc, h.ApiTokenCache, req); !pass {
 492                 err = BadAuthorizationHeader
 493                 status = http.StatusForbidden
 494                 return
 495         }
 496
 497         // Copy ArvadosClient struct and use the client's API token
 498         arvclient := *kc.Arvados
 499         arvclient.ApiToken = tok
 500         kc.Arvados = &arvclient
 501
 502         // Check if the client specified the number of replicas
 503         if req.Header.Get("X-Keep-Desired-Replicas") != "" {
 504                 var r int
 505                 _, err := fmt.Sscanf(req.Header.Get(keepclient.X_Keep_Desired_Replicas), "%d", &r)
 506                 if err == nil {
 507                         kc.Want_replicas = r
 508                 }
 509         }
 510
 511         // Now try to put the block through
 512         if locatorIn == "" {
 513                 bytes, err2 := ioutil.ReadAll(req.Body)
 514                 if err2 != nil {
 515                         err = fmt.Errorf("Error reading request body: %s", err2)
 516                         status = http.StatusInternalServerError
 517                         return
 518                 }
 519                 locatorOut, wroteReplicas, err = kc.PutB(bytes)
 520         } else {
 521                 locatorOut, wroteReplicas, err = kc.PutHR(locatorIn, req.Body, expectLength)
 522         }
 523
 524         // Tell the client how many successful PUTs we accomplished
 525         resp.Header().Set(keepclient.X_Keep_Replicas_Stored, fmt.Sprintf("%d", wroteReplicas))
 526
 527         switch err.(type) {
 528         case nil:
 529                 status = http.StatusOK
 530                 _, err = io.WriteString(resp, locatorOut)
 531
 532         case keepclient.OversizeBlockError:
 533                 // Too much data
 534                 status = http.StatusRequestEntityTooLarge
 535
 536         case keepclient.InsufficientReplicasError:
 537                 if wroteReplicas > 0 {
 538                         // At least one write is considered success.  The
 539                         // client can decide if getting less than the number of
 540                         // replications it asked for is a fatal error.
 541                         status = http.StatusOK
 542                         _, err = io.WriteString(resp, locatorOut)
 543                 } else {
 544                         status = http.StatusServiceUnavailable
 545                 }
 546
 547         default:
 548                 status = http.StatusBadGateway
 549         }
 550 }
 551
 552 // ServeHTTP implementation for IndexHandler
 553 // Supports only GET requests for /index/{prefix:[0-9a-f]{0,32}}
 554 // For each keep server found in LocalRoots:
 555 //   Invokes GetIndex using keepclient
 556 //   Expects "complete" response (terminating with blank new line)
 557 //   Aborts on any errors
 558 // Concatenates responses from all those keep servers and returns
 559 func (h *proxyHandler) Index(resp http.ResponseWriter, req *http.Request) {
 560         SetCorsHeaders(resp)
 561
 562         prefix := mux.Vars(req)["prefix"]
 563         var err error
 564         var status int
 565
 566         defer func() {
 567                 if status != http.StatusOK {
 568                         http.Error(resp, err.Error(), status)
 569                 }
 570         }()
 571
 572         kc := h.makeKeepClient(req)
 573         ok, token := CheckAuthorizationHeader(kc, h.ApiTokenCache, req)
 574         if !ok {
 575                 status, err = http.StatusForbidden, BadAuthorizationHeader
 576                 return
 577         }
 578
 579         // Copy ArvadosClient struct and use the client's API token
 580         arvclient := *kc.Arvados
 581         arvclient.ApiToken = token
 582         kc.Arvados = &arvclient
 583
 584         // Only GET method is supported
 585         if req.Method != "GET" {
 586                 status, err = http.StatusNotImplemented, MethodNotSupported
 587                 return
 588         }
 589
 590         // Get index from all LocalRoots and write to resp
 591         var reader io.Reader
 592         for uuid := range kc.LocalRoots() {
 593                 reader, err = kc.GetIndex(uuid, prefix)
 594                 if err != nil {
 595                         status = http.StatusBadGateway
 596                         return
 597                 }
 598
 599                 _, err = io.Copy(resp, reader)
 600                 if err != nil {
 601                         status = http.StatusBadGateway
 602                         return
 603                 }
 604         }
 605
 606         // Got index from all the keep servers and wrote to resp
 607         status = http.StatusOK
 608         resp.Write([]byte("\n"))
 609 }
 610
 611 func (h *proxyHandler) makeKeepClient(req *http.Request) *keepclient.KeepClient {
 612         kc := *h.KeepClient
 613         kc.RequestID = req.Header.Get("X-Request-Id")
 614         kc.HTTPClient = &proxyClient{
 615                 client: &http.Client{
 616                         Timeout:   h.timeout,
 617                         Transport: h.transport,
 618                 },
 619                 proto: req.Proto,
 620         }
 621         return &kc
 622 }