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         "database/sql"
  10         "encoding/json"
  11         "fmt"
  12         "io"
  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         "github.com/jmcvetta/randutil"
  22 )
  23
  24 var pathPattern = `^/arvados/v1/%s(/([0-9a-z]{5})-%s-[0-9a-z]{15})?(.*)$`
  25 var wfRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "workflows", "7fd4e"))
  26 var containersRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "containers", "dz642"))
  27 var containerRequestsRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "container_requests", "xvhdp"))
  28 var collectionsRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "collections", "4zz18"))
  29 var collectionsByPDHRe = regexp.MustCompile(`^/arvados/v1/collections/([0-9a-fA-F]{32}\+[0-9]+)+$`)
  30 var linksRe = regexp.MustCompile(fmt.Sprintf(pathPattern, "links", "o0j2j"))
  31
  32 func (h *Handler) remoteClusterRequest(remoteID string, req *http.Request) (*http.Response, error) {
  33         remote, ok := h.Cluster.RemoteClusters[remoteID]
  34         if !ok {
  35                 return 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, 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         collectionsRequestsHandler := &genericFederatedRequestHandler{next, h, collectionsRe,
  94                 []federatedRequestDelegate{fetchRemoteCollectionByUUID, fetchRemoteCollectionByPDH}}
  95         linksRequestsHandler := &genericFederatedRequestHandler{next, h, linksRe, nil}
  96
  97         mux.Handle("/arvados/v1/workflows", wfHandler)
  98         mux.Handle("/arvados/v1/workflows/", wfHandler)
  99         mux.Handle("/arvados/v1/containers", containersHandler)
 100         mux.Handle("/arvados/v1/containers/", containersHandler)
 101         mux.Handle("/arvados/v1/container_requests", containerRequestsHandler)
 102         mux.Handle("/arvados/v1/container_requests/", containerRequestsHandler)
 103         mux.Handle("/arvados/v1/collections", collectionsRequestsHandler)
 104         mux.Handle("/arvados/v1/collections/", collectionsRequestsHandler)
 105         mux.Handle("/arvados/v1/links", linksRequestsHandler)
 106         mux.Handle("/arvados/v1/links/", linksRequestsHandler)
 107         mux.Handle("/", next)
 108
 109         return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
 110                 parts := strings.Split(req.Header.Get("Authorization"), "/")
 111                 alreadySalted := (len(parts) == 3 && parts[0] == "Bearer v2" && len(parts[2]) == 40)
 112
 113                 if alreadySalted ||
 114                         strings.Index(req.Header.Get("Via"), "arvados-controller") != -1 {
 115                         // The token is already salted, or this is a
 116                         // request from another instance of
 117                         // arvados-controller.  In either case, we
 118                         // don't want to proxy this query, so just
 119                         // continue down the instance handler stack.
 120                         next.ServeHTTP(w, req)
 121                         return
 122                 }
 123
 124                 mux.ServeHTTP(w, req)
 125         })
 126
 127         return mux
 128 }
 129
 130 type CurrentUser struct {
 131         Authorization arvados.APIClientAuthorization
 132         UUID          string
 133 }
 134
 135 // validateAPItoken extracts the token from the provided http request,
 136 // checks it again api_client_authorizations table in the database,
 137 // and fills in the token scope and user UUID.  Does not handle remote
 138 // tokens unless they are already in the database and not expired.
 139 func (h *Handler) validateAPItoken(req *http.Request, token string) (*CurrentUser, error) {
 140         user := CurrentUser{Authorization: arvados.APIClientAuthorization{APIToken: token}}
 141         db, err := h.db(req)
 142         if err != nil {
 143                 return nil, err
 144         }
 145
 146         var uuid string
 147         if strings.HasPrefix(token, "v2/") {
 148                 sp := strings.Split(token, "/")
 149                 uuid = sp[1]
 150                 token = sp[2]
 151         }
 152         user.Authorization.APIToken = token
 153         var scopes string
 154         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)
 155         if err != nil {
 156                 return nil, err
 157         }
 158         if uuid != "" && user.Authorization.UUID != uuid {
 159                 return nil, fmt.Errorf("UUID embedded in v2 token did not match record")
 160         }
 161         err = json.Unmarshal([]byte(scopes), &user.Authorization.Scopes)
 162         if err != nil {
 163                 return nil, err
 164         }
 165         return &user, nil
 166 }
 167
 168 func (h *Handler) createAPItoken(req *http.Request, userUUID string, scopes []string) (*arvados.APIClientAuthorization, error) {
 169         db, err := h.db(req)
 170         if err != nil {
 171                 return nil, err
 172         }
 173         rd, err := randutil.String(15, "abcdefghijklmnopqrstuvwxyz0123456789")
 174         if err != nil {
 175                 return nil, err
 176         }
 177         uuid := fmt.Sprintf("%v-gj3su-%v", h.Cluster.ClusterID, rd)
 178         token, err := randutil.String(50, "abcdefghijklmnopqrstuvwxyz0123456789")
 179         if err != nil {
 180                 return nil, err
 181         }
 182         if len(scopes) == 0 {
 183                 scopes = append(scopes, "all")
 184         }
 185         scopesjson, err := json.Marshal(scopes)
 186         if err != nil {
 187                 return nil, err
 188         }
 189         _, err = db.ExecContext(req.Context(),
 190                 `INSERT INTO api_client_authorizations
 191 (uuid, api_token, expires_at, scopes,
 192 user_id,
 193 api_client_id, created_at, updated_at)
 194 VALUES ($1, $2, CURRENT_TIMESTAMP + INTERVAL '2 weeks', $3,
 195 (SELECT id FROM users WHERE users.uuid=$4 LIMIT 1),
 196 0, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP)`,
 197                 uuid, token, string(scopesjson), userUUID)
 198
 199         if err != nil {
 200                 return nil, err
 201         }
 202
 203         return &arvados.APIClientAuthorization{
 204                 UUID:      uuid,
 205                 APIToken:  token,
 206                 ExpiresAt: "",
 207                 Scopes:    scopes}, nil
 208 }
 209
 210 // Extract the auth token supplied in req, and replace it with a
 211 // salted token for the remote cluster.
 212 func (h *Handler) saltAuthToken(req *http.Request, remote string) (updatedReq *http.Request, err error) {
 213         updatedReq = (&http.Request{
 214                 Method:        req.Method,
 215                 URL:           req.URL,
 216                 Header:        req.Header,
 217                 Body:          req.Body,
 218                 ContentLength: req.ContentLength,
 219                 Host:          req.Host,
 220         }).WithContext(req.Context())
 221
 222         creds := auth.NewCredentials()
 223         creds.LoadTokensFromHTTPRequest(updatedReq)
 224         if len(creds.Tokens) == 0 && updatedReq.Header.Get("Content-Type") == "application/x-www-form-encoded" {
 225                 // Override ParseForm's 10MiB limit by ensuring
 226                 // req.Body is a *http.maxBytesReader.
 227                 updatedReq.Body = http.MaxBytesReader(nil, updatedReq.Body, 1<<28) // 256MiB. TODO: use MaxRequestSize from discovery doc or config.
 228                 if err := creds.LoadTokensFromHTTPRequestBody(updatedReq); err != nil {
 229                         return nil, err
 230                 }
 231                 // Replace req.Body with a buffer that re-encodes the
 232                 // form without api_token, in case we end up
 233                 // forwarding the request.
 234                 if updatedReq.PostForm != nil {
 235                         updatedReq.PostForm.Del("api_token")
 236                 }
 237                 updatedReq.Body = ioutil.NopCloser(bytes.NewBufferString(updatedReq.PostForm.Encode()))
 238         }
 239         if len(creds.Tokens) == 0 {
 240                 return updatedReq, nil
 241         }
 242
 243         token, err := auth.SaltToken(creds.Tokens[0], remote)
 244
 245         if err == auth.ErrObsoleteToken {
 246                 // If the token exists in our own database, salt it
 247                 // for the remote. Otherwise, assume it was issued by
 248                 // the remote, and pass it through unmodified.
 249                 currentUser, err := h.validateAPItoken(req, creds.Tokens[0])
 250                 if err == sql.ErrNoRows {
 251                         // Not ours; pass through unmodified.
 252                         token = creds.Tokens[0]
 253                 } else if err != nil {
 254                         return nil, err
 255                 } else {
 256                         // Found; make V2 version and salt it.
 257                         token, err = auth.SaltToken(currentUser.Authorization.TokenV2(), remote)
 258                         if err != nil {
 259                                 return nil, err
 260                         }
 261                 }
 262         } else if err != nil {
 263                 return nil, err
 264         }
 265         updatedReq.Header = http.Header{}
 266         for k, v := range req.Header {
 267                 if k != "Authorization" {
 268                         updatedReq.Header[k] = v
 269                 }
 270         }
 271         updatedReq.Header.Set("Authorization", "Bearer "+token)
 272
 273         // Remove api_token=... from the the query string, in case we
 274         // end up forwarding the request.
 275         if values, err := url.ParseQuery(updatedReq.URL.RawQuery); err != nil {
 276                 return nil, err
 277         } else if _, ok := values["api_token"]; ok {
 278                 delete(values, "api_token")
 279                 updatedReq.URL = &url.URL{
 280                         Scheme:   req.URL.Scheme,
 281                         Host:     req.URL.Host,
 282                         Path:     req.URL.Path,
 283                         RawPath:  req.URL.RawPath,
 284                         RawQuery: values.Encode(),
 285                 }
 286         }
 287         return updatedReq, nil
 288 }