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         "bytes"
   9         "context"
  10         "database/sql"
  11         "encoding/json"
  12         "fmt"
  13         "io"
  14         "io/ioutil"
  15         "net/http"
  16         "net/url"
  17         "regexp"
  18         "strings"
  19
  20         "git.curoverse.com/arvados.git/sdk/go/arvados"
  21         "git.curoverse.com/arvados.git/sdk/go/auth"
  22         "github.com/jmcvetta/randutil"
  23 )
  24
  25 var pathPattern = `^/arvados/v1/%s(/([0-9a-z]{5})-%s-[0-9a-z]{15})?(.*)$`
  26 var wfRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "workflows", "7fd4e"))
  27 var containersRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "containers", "dz642"))
  28 var containerRequestsRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "container_requests", "xvhdp"))
  29 var collectionRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "collections", "4zz18"))
  30 var collectionByPDHRe = regexp.MustCompile(`^/arvados/v1/collections/([0-9a-fA-F]{32}\+[0-9]+)+$`)
  31
  32 func (h *Handler) remoteClusterRequest(remoteID string, req *http.Request) (*http.Response, context.CancelFunc, error) {
  33         remote, ok := h.Cluster.RemoteClusters[remoteID]
  34         if !ok {
  35                 return nil, nil, HTTPError{fmt.Sprintf("no proxy available for cluster %v", remoteID), http.StatusNotFound}
  36         }
  37         scheme := remote.Scheme
  38         if scheme == "" {
  39                 scheme = "https"
  40         }
  41         saltedReq, err := h.saltAuthToken(req, remoteID)
  42         if err != nil {
  43                 return nil, nil, err
  44         }
  45         urlOut := &url.URL{
  46                 Scheme:   scheme,
  47                 Host:     remote.Host,
  48                 Path:     saltedReq.URL.Path,
  49                 RawPath:  saltedReq.URL.RawPath,
  50                 RawQuery: saltedReq.URL.RawQuery,
  51         }
  52         client := h.secureClient
  53         if remote.Insecure {
  54                 client = h.insecureClient
  55         }
  56         return h.proxy.Do(saltedReq, urlOut, client)
  57 }
  58
  59 // Buffer request body, parse form parameters in request, and then
  60 // replace original body with the buffer so it can be re-read by
  61 // downstream proxy steps.
  62 func loadParamsFromForm(req *http.Request) error {
  63         var postBody *bytes.Buffer
  64         if req.Body != nil && req.Header.Get("Content-Type") == "application/x-www-form-urlencoded" {
  65                 var cl int64
  66                 if req.ContentLength > 0 {
  67                         cl = req.ContentLength
  68                 }
  69                 postBody = bytes.NewBuffer(make([]byte, 0, cl))
  70                 originalBody := req.Body
  71                 defer originalBody.Close()
  72                 req.Body = ioutil.NopCloser(io.TeeReader(req.Body, postBody))
  73         }
  74
  75         err := req.ParseForm()
  76         if err != nil {
  77                 return err
  78         }
  79
  80         if req.Body != nil && postBody != nil {
  81                 req.Body = ioutil.NopCloser(postBody)
  82         }
  83         return nil
  84 }
  85
  86 func (h *Handler) setupProxyRemoteCluster(next http.Handler) http.Handler {
  87         mux := http.NewServeMux()
  88
  89         wfHandler := &genericFederatedRequestHandler{next, h, wfRe, nil}
  90         containersHandler := &genericFederatedRequestHandler{next, h, containersRe, nil}
  91         containerRequestsHandler := &genericFederatedRequestHandler{next, h, containerRequestsRe,
  92                 []federatedRequestDelegate{remoteContainerRequestCreate}}
  93
  94         mux.Handle("/arvados/v1/workflows", wfHandler)
  95         mux.Handle("/arvados/v1/workflows/", wfHandler)
  96         mux.Handle("/arvados/v1/containers", containersHandler)
  97         mux.Handle("/arvados/v1/containers/", containersHandler)
  98         mux.Handle("/arvados/v1/container_requests", containerRequestsHandler)
  99         mux.Handle("/arvados/v1/container_requests/", containerRequestsHandler)
 100         mux.Handle("/arvados/v1/collections", next)
 101         mux.Handle("/arvados/v1/collections/", &collectionFederatedRequestHandler{next, h})
 102         mux.Handle("/", next)
 103
 104         return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
 105                 parts := strings.Split(req.Header.Get("Authorization"), "/")
 106                 alreadySalted := (len(parts) == 3 && parts[0] == "Bearer v2" && len(parts[2]) == 40)
 107
 108                 if alreadySalted ||
 109                         strings.Index(req.Header.Get("Via"), "arvados-controller") != -1 {
 110                         // The token is already salted, or this is a
 111                         // request from another instance of
 112                         // arvados-controller.  In either case, we
 113                         // don't want to proxy this query, so just
 114                         // continue down the instance handler stack.
 115                         next.ServeHTTP(w, req)
 116                         return
 117                 }
 118
 119                 mux.ServeHTTP(w, req)
 120         })
 121
 122         return mux
 123 }
 124
 125 type CurrentUser struct {
 126         Authorization arvados.APIClientAuthorization
 127         UUID          string
 128 }
 129
 130 // validateAPItoken extracts the token from the provided http request,
 131 // checks it again api_client_authorizations table in the database,
 132 // and fills in the token scope and user UUID.  Does not handle remote
 133 // tokens unless they are already in the database and not expired.
 134 func (h *Handler) validateAPItoken(req *http.Request, token string) (*CurrentUser, error) {
 135         user := CurrentUser{Authorization: arvados.APIClientAuthorization{APIToken: token}}
 136         db, err := h.db(req)
 137         if err != nil {
 138                 return nil, err
 139         }
 140
 141         var uuid string
 142         if strings.HasPrefix(token, "v2/") {
 143                 sp := strings.Split(token, "/")
 144                 uuid = sp[1]
 145                 token = sp[2]
 146         }
 147         user.Authorization.APIToken = token
 148         var scopes string
 149         err = db.QueryRowContext(req.Context(), `SELECT api_client_authorizations.uuid, api_client_authorizations.scopes, 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`, token).Scan(&user.Authorization.UUID, &scopes, &user.UUID)
 150         if err != nil {
 151                 return nil, err
 152         }
 153         if uuid != "" && user.Authorization.UUID != uuid {
 154                 return nil, fmt.Errorf("UUID embedded in v2 token did not match record")
 155         }
 156         err = json.Unmarshal([]byte(scopes), &user.Authorization.Scopes)
 157         if err != nil {
 158                 return nil, err
 159         }
 160         return &user, nil
 161 }
 162
 163 func (h *Handler) createAPItoken(req *http.Request, userUUID string, scopes []string) (*arvados.APIClientAuthorization, error) {
 164         db, err := h.db(req)
 165         if err != nil {
 166                 return nil, err
 167         }
 168         rd, err := randutil.String(15, "abcdefghijklmnopqrstuvwxyz0123456789")
 169         if err != nil {
 170                 return nil, err
 171         }
 172         uuid := fmt.Sprintf("%v-gj3su-%v", h.Cluster.ClusterID, rd)
 173         token, err := randutil.String(50, "abcdefghijklmnopqrstuvwxyz0123456789")
 174         if err != nil {
 175                 return nil, err
 176         }
 177         if len(scopes) == 0 {
 178                 scopes = append(scopes, "all")
 179         }
 180         scopesjson, err := json.Marshal(scopes)
 181         if err != nil {
 182                 return nil, err
 183         }
 184         _, err = db.ExecContext(req.Context(),
 185                 `INSERT INTO api_client_authorizations
 186 (uuid, api_token, expires_at, scopes,
 187 user_id,
 188 api_client_id, created_at, updated_at)
 189 VALUES ($1, $2, CURRENT_TIMESTAMP + INTERVAL '2 weeks', $3,
 190 (SELECT id FROM users WHERE users.uuid=$4 LIMIT 1),
 191 0, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP)`,
 192                 uuid, token, string(scopesjson), userUUID)
 193
 194         if err != nil {
 195                 return nil, err
 196         }
 197
 198         return &arvados.APIClientAuthorization{
 199                 UUID:      uuid,
 200                 APIToken:  token,
 201                 ExpiresAt: "",
 202                 Scopes:    scopes}, nil
 203 }
 204
 205 // Extract the auth token supplied in req, and replace it with a
 206 // salted token for the remote cluster.
 207 func (h *Handler) saltAuthToken(req *http.Request, remote string) (updatedReq *http.Request, err error) {
 208         updatedReq = (&http.Request{
 209                 Method:        req.Method,
 210                 URL:           req.URL,
 211                 Header:        req.Header,
 212                 Body:          req.Body,
 213                 ContentLength: req.ContentLength,
 214                 Host:          req.Host,
 215         }).WithContext(req.Context())
 216
 217         creds := auth.NewCredentials()
 218         creds.LoadTokensFromHTTPRequest(updatedReq)
 219         if len(creds.Tokens) == 0 && updatedReq.Header.Get("Content-Type") == "application/x-www-form-encoded" {
 220                 // Override ParseForm's 10MiB limit by ensuring
 221                 // req.Body is a *http.maxBytesReader.
 222                 updatedReq.Body = http.MaxBytesReader(nil, updatedReq.Body, 1<<28) // 256MiB. TODO: use MaxRequestSize from discovery doc or config.
 223                 if err := creds.LoadTokensFromHTTPRequestBody(updatedReq); err != nil {
 224                         return nil, err
 225                 }
 226                 // Replace req.Body with a buffer that re-encodes the
 227                 // form without api_token, in case we end up
 228                 // forwarding the request.
 229                 if updatedReq.PostForm != nil {
 230                         updatedReq.PostForm.Del("api_token")
 231                 }
 232                 updatedReq.Body = ioutil.NopCloser(bytes.NewBufferString(updatedReq.PostForm.Encode()))
 233         }
 234         if len(creds.Tokens) == 0 {
 235                 return updatedReq, nil
 236         }
 237
 238         token, err := auth.SaltToken(creds.Tokens[0], remote)
 239
 240         if err == auth.ErrObsoleteToken {
 241                 // If the token exists in our own database, salt it
 242                 // for the remote. Otherwise, assume it was issued by
 243                 // the remote, and pass it through unmodified.
 244                 currentUser, err := h.validateAPItoken(req, creds.Tokens[0])
 245                 if err == sql.ErrNoRows {
 246                         // Not ours; pass through unmodified.
 247                         token = creds.Tokens[0]
 248                 } else if err != nil {
 249                         return nil, err
 250                 } else {
 251                         // Found; make V2 version and salt it.
 252                         token, err = auth.SaltToken(currentUser.Authorization.TokenV2(), remote)
 253                         if err != nil {
 254                                 return nil, err
 255                         }
 256                 }
 257         } else if err != nil {
 258                 return nil, err
 259         }
 260         updatedReq.Header = http.Header{}
 261         for k, v := range req.Header {
 262                 if k != "Authorization" {
 263                         updatedReq.Header[k] = v
 264                 }
 265         }
 266         updatedReq.Header.Set("Authorization", "Bearer "+token)
 267
 268         // Remove api_token=... from the the query string, in case we
 269         // end up forwarding the request.
 270         if values, err := url.ParseQuery(updatedReq.URL.RawQuery); err != nil {
 271                 return nil, err
 272         } else if _, ok := values["api_token"]; ok {
 273                 delete(values, "api_token")
 274                 updatedReq.URL = &url.URL{
 275                         Scheme:   req.URL.Scheme,
 276                         Host:     req.URL.Host,
 277                         Path:     req.URL.Path,
 278                         RawPath:  req.URL.RawPath,
 279                         RawQuery: values.Encode(),
 280                 }
 281         }
 282         return updatedReq, nil
 283 }