lib/controller/federation.go

   1 // Copyright (C) The Arvados Authors. All rights reserved.
   2 //
   3 // SPDX-License-Identifier: AGPL-3.0
   4
   5 package controller
   6
   7 import (
   8         "bufio"
   9         "bytes"
  10         "database/sql"
  11         "encoding/json"
  12         "fmt"
  13         "io/ioutil"
  14         "net/http"
  15         "net/url"
  16         "regexp"
  17         "strings"
  18
  19         "git.curoverse.com/arvados.git/sdk/go/arvados"
  20         "git.curoverse.com/arvados.git/sdk/go/auth"
  21         "git.curoverse.com/arvados.git/sdk/go/httpserver"
  22         "git.curoverse.com/arvados.git/sdk/go/keepclient"
  23 )
  24
  25 var wfRe = regexp.MustCompile(`^/arvados/v1/workflows/([0-9a-z]{5})-[^/]+$`)
  26 var collectionRe = regexp.MustCompile(`^/arvados/v1/collections/([0-9a-z]{5})-[^/]+$`)
  27 var collectionByPDHRe = regexp.MustCompile(`^/arvados/v1/collections/([0-9a-fA-F]{32}\+[0-9]+)+$`)
  28
  29 type genericFederatedRequestHandler struct {
  30         next    http.Handler
  31         handler *Handler
  32 }
  33
  34 type collectionFederatedRequestHandler struct {
  35         next    http.Handler
  36         handler *Handler
  37 }
  38
  39 func (h *Handler) remoteClusterRequest(remoteID string, w http.ResponseWriter, req *http.Request, filter ResponseFilter) {
  40         remote, ok := h.Cluster.RemoteClusters[remoteID]
  41         if !ok {
  42                 httpserver.Error(w, "no proxy available for cluster "+remoteID, http.StatusNotFound)
  43                 return
  44         }
  45         scheme := remote.Scheme
  46         if scheme == "" {
  47                 scheme = "https"
  48         }
  49         err := h.saltAuthToken(req, remoteID)
  50         if err != nil {
  51                 httpserver.Error(w, err.Error(), http.StatusBadRequest)
  52                 return
  53         }
  54         urlOut := &url.URL{
  55                 Scheme:   scheme,
  56                 Host:     remote.Host,
  57                 Path:     req.URL.Path,
  58                 RawPath:  req.URL.RawPath,
  59                 RawQuery: req.URL.RawQuery,
  60         }
  61         client := h.secureClient
  62         if remote.Insecure {
  63                 client = h.insecureClient
  64         }
  65         h.proxy.Do(w, req, urlOut, client, filter)
  66 }
  67
  68 func (h *genericFederatedRequestHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
  69         m := wfRe.FindStringSubmatch(req.URL.Path)
  70         if len(m) < 2 || m[1] == h.handler.Cluster.ClusterID {
  71                 h.next.ServeHTTP(w, req)
  72                 return
  73         }
  74         h.handler.remoteClusterRequest(m[1], w, req, nil)
  75 }
  76
  77 type rewriteSignaturesClusterId string
  78
  79 func (clusterId rewriteSignaturesClusterId) rewriteSignatures(resp *http.Response) (newResponse *http.Response, err error) {
  80         if resp.StatusCode != 200 {
  81                 return resp, nil
  82         }
  83
  84         originalBody := resp.Body
  85         defer originalBody.Close()
  86
  87         var col arvados.Collection
  88         err = json.NewDecoder(resp.Body).Decode(&col)
  89         if err != nil {
  90                 return nil, err
  91         }
  92
  93         // rewriting signatures will make manifest text 5-10% bigger so calculate
  94         // capacity accordingly
  95         updatedManifest := bytes.NewBuffer(make([]byte, 0, int(float64(len(col.ManifestText))*1.1)))
  96
  97         scanner := bufio.NewScanner(strings.NewReader(col.ManifestText))
  98         scanner.Buffer(make([]byte, 1048576), len(col.ManifestText))
  99         for scanner.Scan() {
 100                 line := scanner.Text()
 101                 tokens := strings.Split(line, " ")
 102                 if len(tokens) < 3 {
 103                         return nil, fmt.Errorf("Invalid stream (<3 tokens): %q", line)
 104                 }
 105
 106                 updatedManifest.WriteString(tokens[0])
 107                 for _, token := range tokens[1:] {
 108                         updatedManifest.WriteString(" ")
 109                         m := keepclient.SignedLocatorRe.FindStringSubmatch(token)
 110                         if m != nil {
 111                                 // Rewrite the block signature to be a remote signature
 112                                 fmt.Fprintf(updatedManifest, "%s%s%s+R%s-%s%s", m[1], m[2], m[3], clusterId, m[5][2:], m[8])
 113                         } else {
 114                                 updatedManifest.WriteString(token)
 115                         }
 116
 117                 }
 118                 updatedManifest.WriteString("\n")
 119         }
 120
 121         col.ManifestText = updatedManifest.String()
 122
 123         newbody, err := json.Marshal(col)
 124         if err != nil {
 125                 return nil, err
 126         }
 127
 128         buf := bytes.NewBuffer(newbody)
 129         resp.Body = ioutil.NopCloser(buf)
 130         resp.ContentLength = int64(buf.Len())
 131         resp.Header.Set("Content-Length", fmt.Sprintf("%v", buf.Len()))
 132
 133         return resp, nil
 134 }
 135
 136 type searchLocalClusterForPDH struct {
 137         needSearchFederation bool
 138 }
 139
 140 func (s *searchLocalClusterForPDH) filterLocalClusterResponse(resp *http.Response) (newResponse *http.Response, err error) {
 141         if resp.StatusCode == 404 {
 142                 // Suppress returning this result, because we want to
 143                 // search the federation.
 144                 s.needSearchFederation = true
 145                 return nil, nil
 146         }
 147         return resp, nil
 148 }
 149
 150 func (h *collectionFederatedRequestHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 151         m := collectionByPDHRe.FindStringSubmatch(req.URL.Path)
 152         if len(m) == 2 {
 153                 urlOut, insecure, err := findRailsAPI(h.handler.Cluster, h.handler.NodeProfile)
 154                 if err != nil {
 155                         httpserver.Error(w, err.Error(), http.StatusInternalServerError)
 156                         return
 157                 }
 158
 159                 urlOut = &url.URL{
 160                         Scheme:   urlOut.Scheme,
 161                         Host:     urlOut.Host,
 162                         Path:     req.URL.Path,
 163                         RawPath:  req.URL.RawPath,
 164                         RawQuery: req.URL.RawQuery,
 165                 }
 166                 client := h.handler.secureClient
 167                 if insecure {
 168                         client = h.handler.insecureClient
 169                 }
 170                 sf := &searchLocalClusterForPDH{false}
 171                 h.handler.proxy.Do(w, req, urlOut, client, sf.filterLocalClusterResponse)
 172                 if !sf.needSearchFederation {
 173                         // a response was sent
 174                         return
 175                 }
 176         }
 177
 178         m = collectionRe.FindStringSubmatch(req.URL.Path)
 179         if len(m) < 2 || m[1] == h.handler.Cluster.ClusterID {
 180                 h.next.ServeHTTP(w, req)
 181                 return
 182         }
 183         h.handler.remoteClusterRequest(m[1], w, req,
 184                 rewriteSignaturesClusterId(m[1]).rewriteSignatures)
 185 }
 186
 187 func (h *Handler) setupProxyRemoteCluster(next http.Handler) http.Handler {
 188         mux := http.NewServeMux()
 189         mux.Handle("/arvados/v1/workflows", next)
 190         mux.Handle("/arvados/v1/workflows/", &genericFederatedRequestHandler{next, h})
 191         mux.Handle("/arvados/v1/collections", next)
 192         mux.Handle("/arvados/v1/collections/", &collectionFederatedRequestHandler{next, h})
 193         mux.Handle("/", next)
 194
 195         return mux
 196 }
 197
 198 type CurrentUser struct {
 199         Authorization arvados.APIClientAuthorization
 200         UUID          string
 201 }
 202
 203 func (h *Handler) validateAPItoken(req *http.Request, user *CurrentUser) error {
 204         db, err := h.db(req)
 205         if err != nil {
 206                 return err
 207         }
 208         return db.QueryRowContext(req.Context(), `SELECT api_client_authorizations.uuid, users.uuid FROM api_client_authorizations JOIN users on api_client_authorizations.user_id=users.id WHERE api_token=$1 AND (expires_at IS NULL OR expires_at > current_timestamp) LIMIT 1`, user.Authorization.APIToken).Scan(&user.Authorization.UUID, &user.UUID)
 209 }
 210
 211 // Extract the auth token supplied in req, and replace it with a
 212 // salted token for the remote cluster.
 213 func (h *Handler) saltAuthToken(req *http.Request, remote string) error {
 214         creds := auth.NewCredentials()
 215         creds.LoadTokensFromHTTPRequest(req)
 216         if len(creds.Tokens) == 0 && req.Header.Get("Content-Type") == "application/x-www-form-encoded" {
 217                 // Override ParseForm's 10MiB limit by ensuring
 218                 // req.Body is a *http.maxBytesReader.
 219                 req.Body = http.MaxBytesReader(nil, req.Body, 1<<28) // 256MiB. TODO: use MaxRequestSize from discovery doc or config.
 220                 if err := creds.LoadTokensFromHTTPRequestBody(req); err != nil {
 221                         return err
 222                 }
 223                 // Replace req.Body with a buffer that re-encodes the
 224                 // form without api_token, in case we end up
 225                 // forwarding the request.
 226                 if req.PostForm != nil {
 227                         req.PostForm.Del("api_token")
 228                 }
 229                 req.Body = ioutil.NopCloser(bytes.NewBufferString(req.PostForm.Encode()))
 230         }
 231         if len(creds.Tokens) == 0 {
 232                 return nil
 233         }
 234         token, err := auth.SaltToken(creds.Tokens[0], remote)
 235         if err == auth.ErrObsoleteToken {
 236                 // If the token exists in our own database, salt it
 237                 // for the remote. Otherwise, assume it was issued by
 238                 // the remote, and pass it through unmodified.
 239                 currentUser := CurrentUser{Authorization: arvados.APIClientAuthorization{APIToken: creds.Tokens[0]}}
 240                 err = h.validateAPItoken(req, &currentUser)
 241                 if err == sql.ErrNoRows {
 242                         // Not ours; pass through unmodified.
 243                         token = currentUser.Authorization.APIToken
 244                 } else if err != nil {
 245                         return err
 246                 } else {
 247                         // Found; make V2 version and salt it.
 248                         token, err = auth.SaltToken(currentUser.Authorization.TokenV2(), remote)
 249                         if err != nil {
 250                                 return err
 251                         }
 252                 }
 253         } else if err != nil {
 254                 return err
 255         }
 256         req.Header.Set("Authorization", "Bearer "+token)
 257
 258         // Remove api_token=... from the the query string, in case we
 259         // end up forwarding the request.
 260         if values, err := url.ParseQuery(req.URL.RawQuery); err != nil {
 261                 return err
 262         } else if _, ok := values["api_token"]; ok {
 263                 delete(values, "api_token")
 264                 req.URL.RawQuery = values.Encode()
 265         }
 266         return nil
 267 }