src/reclaim/plugin_rest_openid_connect.c

   1 /*
   2    This file is part of GNUnet.
   3    Copyright (C) 2012-2018 GNUnet e.V.
   4
   5    GNUnet is free software: you can redistribute it and/or modify it
   6    under the terms of the GNU Affero General Public License as published
   7    by the Free Software Foundation, either version 3 of the License,
   8    or (at your option) any later version.
   9
  10    GNUnet is distributed in the hope that it will be useful, but
  11    WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Affero General Public License for more details.
  14
  15    You should have received a copy of the GNU Affero General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17
  18    SPDX-License-Identifier: AGPL3.0-or-later
  19  */
  20 /**
  21  * @author Martin Schanzenbach
  22  * @author Philippe Buschmann
  23  * @file identity/plugin_rest_openid_connect.c
  24  * @brief GNUnet Namestore REST plugin
  25  *
  26  */
  27 #include "platform.h"
  28 #include <inttypes.h>
  29 #include <jansson.h>
  30
  31 #include "gnunet_gns_service.h"
  32 #include "gnunet_gnsrecord_lib.h"
  33 #include "gnunet_identity_service.h"
  34 #include "gnunet_namestore_service.h"
  35 #include "gnunet_reclaim_lib.h"
  36 #include "gnunet_reclaim_service.h"
  37 #include "gnunet_rest_lib.h"
  38 #include "gnunet_rest_plugin.h"
  39 #include "gnunet_signatures.h"
  40 #include "microhttpd.h"
  41 #include "oidc_helper.h"
  42 /**
  43  * REST root namespace
  44  */
  45 #define GNUNET_REST_API_NS_OIDC "/openid"
  46
  47 /**
  48  * Authorize endpoint
  49  */
  50 #define GNUNET_REST_API_NS_AUTHORIZE "/openid/authorize"
  51
  52 /**
  53  * Token endpoint
  54  */
  55 #define GNUNET_REST_API_NS_TOKEN "/openid/token"
  56
  57 /**
  58  * UserInfo endpoint
  59  */
  60 #define GNUNET_REST_API_NS_USERINFO "/openid/userinfo"
  61
  62 /**
  63  * Login namespace
  64  */
  65 #define GNUNET_REST_API_NS_LOGIN "/openid/login"
  66
  67 /**
  68  * State while collecting all egos
  69  */
  70 #define ID_REST_STATE_INIT 0
  71
  72 /**
  73  * Done collecting egos
  74  */
  75 #define ID_REST_STATE_POST_INIT 1
  76
  77 /**
  78  * OIDC grant_type key
  79  */
  80 #define OIDC_GRANT_TYPE_KEY "grant_type"
  81
  82 /**
  83  * OIDC grant_type key
  84  */
  85 #define OIDC_GRANT_TYPE_VALUE "authorization_code"
  86
  87 /**
  88  * OIDC code key
  89  */
  90 #define OIDC_CODE_KEY "code"
  91
  92 /**
  93  * OIDC response_type key
  94  */
  95 #define OIDC_RESPONSE_TYPE_KEY "response_type"
  96
  97 /**
  98  * OIDC client_id key
  99  */
 100 #define OIDC_CLIENT_ID_KEY "client_id"
 101
 102 /**
 103  * OIDC scope key
 104  */
 105 #define OIDC_SCOPE_KEY "scope"
 106
 107 /**
 108  * OIDC redirect_uri key
 109  */
 110 #define OIDC_REDIRECT_URI_KEY "redirect_uri"
 111
 112 /**
 113  * OIDC state key
 114  */
 115 #define OIDC_STATE_KEY "state"
 116
 117 /**
 118  * OIDC nonce key
 119  */
 120 #define OIDC_NONCE_KEY "nonce"
 121
 122 /**
 123  * OIDC claims key
 124  */
 125 #define OIDC_CLAIMS_KEY "claims"
 126
 127 /**
 128  * OIDC PKCE code challenge
 129  */
 130 #define OIDC_CODE_CHALLENGE_KEY "code_challenge"
 131
 132 /**
 133  * OIDC PKCE code verifier
 134  */
 135 #define OIDC_CODE_VERIFIER_KEY "code_verifier"
 136
 137 /**
 138  * OIDC cookie expiration (in seconds)
 139  */
 140 #define OIDC_COOKIE_EXPIRATION 3
 141
 142 /**
 143  * OIDC cookie header key
 144  */
 145 #define OIDC_COOKIE_HEADER_KEY "cookie"
 146
 147 /**
 148  * OIDC cookie header information key
 149  */
 150 #define OIDC_AUTHORIZATION_HEADER_KEY "authorization"
 151
 152 /**
 153  * OIDC cookie header information key
 154  */
 155 #define OIDC_COOKIE_HEADER_INFORMATION_KEY "Identity="
 156
 157 /**
 158  * OIDC cookie header if user cancelled
 159  */
 160 #define OIDC_COOKIE_HEADER_ACCESS_DENIED "Identity=Denied"
 161
 162 /**
 163  * OIDC expected response_type while authorizing
 164  */
 165 #define OIDC_EXPECTED_AUTHORIZATION_RESPONSE_TYPE "code"
 166
 167 /**
 168  * OIDC expected scope part while authorizing
 169  */
 170 #define OIDC_EXPECTED_AUTHORIZATION_SCOPE "openid"
 171
 172 /**
 173  * OIDC error key for invalid client
 174  */
 175 #define OIDC_ERROR_KEY_INVALID_CLIENT "invalid_client"
 176
 177 /**
 178  * OIDC error key for invalid scopes
 179  */
 180 #define OIDC_ERROR_KEY_INVALID_SCOPE "invalid_scope"
 181
 182 /**
 183  * OIDC error key for invalid requests
 184  */
 185 #define OIDC_ERROR_KEY_INVALID_REQUEST "invalid_request"
 186
 187 /**
 188  * OIDC error key for invalid tokens
 189  */
 190 #define OIDC_ERROR_KEY_INVALID_TOKEN "invalid_token"
 191
 192 /**
 193  * OIDC error key for invalid cookies
 194  */
 195 #define OIDC_ERROR_KEY_INVALID_COOKIE "invalid_cookie"
 196
 197 /**
 198  * OIDC error key for generic server errors
 199  */
 200 #define OIDC_ERROR_KEY_SERVER_ERROR "server_error"
 201
 202 /**
 203  * OIDC error key for unsupported grants
 204  */
 205 #define OIDC_ERROR_KEY_UNSUPPORTED_GRANT_TYPE "unsupported_grant_type"
 206
 207 /**
 208  * OIDC error key for unsupported response types
 209  */
 210 #define OIDC_ERROR_KEY_UNSUPPORTED_RESPONSE_TYPE "unsupported_response_type"
 211
 212 /**
 213  * OIDC error key for unauthorized clients
 214  */
 215 #define OIDC_ERROR_KEY_UNAUTHORIZED_CLIENT "unauthorized_client"
 216
 217 /**
 218  * OIDC error key for denied access
 219  */
 220 #define OIDC_ERROR_KEY_ACCESS_DENIED "access_denied"
 221
 222
 223 /**
 224  * OIDC ignored parameter array
 225  */
 226 static char *OIDC_ignored_parameter_array[] = { "display",
 227                                                 "prompt",
 228                                                 "ui_locales",
 229                                                 "response_mode",
 230                                                 "id_token_hint",
 231                                                 "login_hint",
 232                                                 "acr_values" };
 233
 234 /**
 235  * OIDC Hash map that keeps track of issued cookies
 236  */
 237 struct GNUNET_CONTAINER_MultiHashMap *OIDC_cookie_jar_map;
 238
 239 /**
 240  * Hash map that links the issued access token to the corresponding ticket and
 241  * ego
 242  */
 243 struct GNUNET_CONTAINER_MultiHashMap *OIDC_access_token_map;
 244
 245 /**
 246  * The configuration handle
 247  */
 248 const struct GNUNET_CONFIGURATION_Handle *cfg;
 249
 250 /**
 251  * HTTP methods allows for this plugin
 252  */
 253 static char *allow_methods;
 254
 255 /**
 256  * @brief struct returned by the initialization function of the plugin
 257  */
 258 struct Plugin
 259 {
 260   const struct GNUNET_CONFIGURATION_Handle *cfg;
 261 };
 262
 263 /**
 264  * OIDC needed variables
 265  */
 266 struct OIDC_Variables
 267 {
 268   /**
 269    * The RP client public key
 270    */
 271   struct GNUNET_CRYPTO_EcdsaPublicKey client_pkey;
 272
 273   /**
 274    * The OIDC client id of the RP
 275    */
 276   char *client_id;
 277
 278   /**
 279    * The OIDC redirect uri
 280    */
 281   char *redirect_uri;
 282
 283   /**
 284    * The list of oidc scopes
 285    */
 286   char *scope;
 287
 288   /**
 289    * The OIDC state
 290    */
 291   char *state;
 292
 293   /**
 294    * The OIDC nonce
 295    */
 296   char *nonce;
 297
 298   /**
 299    * The OIDC claims
 300    */
 301   char *claims;
 302
 303   /**
 304    * The OIDC response type
 305    */
 306   char *response_type;
 307
 308   /**
 309    * The identity chosen by the user to login
 310    */
 311   char *login_identity;
 312
 313   /**
 314    * User cancelled authorization/login
 315    */
 316   int user_cancelled;
 317
 318   /**
 319    * The PKCE code_challenge
 320    */
 321   char *code_challenge;
 322
 323   /**
 324    * The PKCE code_verifier
 325    */
 326   char *code_verifier;
 327
 328   /**
 329    * The response JSON
 330    */
 331   json_t *response;
 332 };
 333
 334 /**
 335  * The ego list
 336  */
 337 struct EgoEntry
 338 {
 339   /**
 340    * DLL
 341    */
 342   struct EgoEntry *next;
 343
 344   /**
 345    * DLL
 346    */
 347   struct EgoEntry *prev;
 348
 349   /**
 350    * Ego Identifier
 351    */
 352   char *identifier;
 353
 354   /**
 355    * Public key string
 356    */
 357   char *keystring;
 358
 359   /**
 360    * The Ego
 361    */
 362   struct GNUNET_IDENTITY_Ego *ego;
 363 };
 364
 365
 366 struct RequestHandle
 367 {
 368   /**
 369    * Ego list
 370    */
 371   struct EgoEntry *ego_head;
 372
 373   /**
 374    * Ego list
 375    */
 376   struct EgoEntry *ego_tail;
 377
 378   /**
 379    * Selected ego
 380    */
 381   struct EgoEntry *ego_entry;
 382
 383   /**
 384    * Pointer to ego private key
 385    */
 386   struct GNUNET_CRYPTO_EcdsaPrivateKey priv_key;
 387
 388   /**
 389    * OIDC variables
 390    */
 391   struct OIDC_Variables *oidc;
 392
 393   /**
 394    * The processing state
 395    */
 396   int state;
 397
 398   /**
 399    * Handle to Identity service.
 400    */
 401   struct GNUNET_IDENTITY_Handle *identity_handle;
 402
 403   /**
 404    * Rest connection
 405    */
 406   struct GNUNET_REST_RequestHandle *rest_handle;
 407
 408   /**
 409    * GNS handle
 410    */
 411   struct GNUNET_GNS_Handle *gns_handle;
 412
 413   /**
 414    * GNS lookup op
 415    */
 416   struct GNUNET_GNS_LookupRequest *gns_op;
 417
 418   /**
 419    * Handle to NAMESTORE
 420    */
 421   struct GNUNET_NAMESTORE_Handle *namestore_handle;
 422
 423   /**
 424    * Iterator for NAMESTORE
 425    */
 426   struct GNUNET_NAMESTORE_ZoneIterator *namestore_handle_it;
 427
 428   /**
 429    * Attribute claim list
 430    */
 431   struct GNUNET_RECLAIM_AttributeList *attr_list;
 432
 433   /**
 434    * Attestation list
 435    */
 436   struct GNUNET_RECLAIM_AttestationList *attests_list;
 437
 438
 439   /**
 440    * IDENTITY Operation
 441    */
 442   struct GNUNET_IDENTITY_Operation *op;
 443
 444   /**
 445    * Identity Provider
 446    */
 447   struct GNUNET_RECLAIM_Handle *idp;
 448
 449   /**
 450    * Idp Operation
 451    */
 452   struct GNUNET_RECLAIM_Operation *idp_op;
 453
 454   /**
 455    * Attribute iterator
 456    */
 457   struct GNUNET_RECLAIM_AttributeIterator *attr_it;
 458
 459   /**
 460    * Attestation iterator
 461    */
 462   struct GNUNET_RECLAIM_AttestationIterator *attest_it;
 463
 464
 465   /**
 466    * Ticket iterator
 467    */
 468   struct GNUNET_RECLAIM_TicketIterator *ticket_it;
 469
 470   /**
 471    * A ticket
 472    */
 473   struct GNUNET_RECLAIM_Ticket ticket;
 474
 475   /**
 476    * Desired timeout for the lookup (default is no timeout).
 477    */
 478   struct GNUNET_TIME_Relative timeout;
 479
 480   /**
 481    * ID of a task associated with the resolution process.
 482    */
 483   struct GNUNET_SCHEDULER_Task *timeout_task;
 484
 485   /**
 486    * The plugin result processor
 487    */
 488   GNUNET_REST_ResultProcessor proc;
 489
 490   /**
 491    * The closure of the result processor
 492    */
 493   void *proc_cls;
 494
 495   /**
 496    * The url
 497    */
 498   char *url;
 499
 500   /**
 501    * The tld for redirect
 502    */
 503   char *tld;
 504
 505   /**
 506    * The redirect prefix
 507    */
 508   char *redirect_prefix;
 509
 510   /**
 511    * The redirect suffix
 512    */
 513   char *redirect_suffix;
 514
 515   /**
 516    * Error response message
 517    */
 518   char *emsg;
 519
 520   /**
 521    * Error response description
 522    */
 523   char *edesc;
 524
 525   /**
 526    * Reponse code
 527    */
 528   int response_code;
 529 };
 530
 531 /**
 532  * Cleanup lookup handle
 533  * @param handle Handle to clean up
 534  */
 535 static void
 536 cleanup_handle (struct RequestHandle *handle)
 537 {
 538   struct EgoEntry *ego_entry;
 539   struct EgoEntry *ego_tmp;
 540
 541   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Cleaning up\n");
 542   if (NULL != handle->timeout_task)
 543     GNUNET_SCHEDULER_cancel (handle->timeout_task);
 544   if (NULL != handle->identity_handle)
 545     GNUNET_IDENTITY_disconnect (handle->identity_handle);
 546   if (NULL != handle->attr_it)
 547     GNUNET_RECLAIM_get_attributes_stop (handle->attr_it);
 548   if (NULL != handle->attest_it)
 549     GNUNET_RECLAIM_get_attestations_stop (handle->attest_it);
 550   if (NULL != handle->ticket_it)
 551     GNUNET_RECLAIM_ticket_iteration_stop (handle->ticket_it);
 552   if (NULL != handle->idp)
 553     GNUNET_RECLAIM_disconnect (handle->idp);
 554   GNUNET_free_non_null (handle->url);
 555   GNUNET_free_non_null (handle->tld);
 556   GNUNET_free_non_null (handle->redirect_prefix);
 557   GNUNET_free_non_null (handle->redirect_suffix);
 558   GNUNET_free_non_null (handle->emsg);
 559   GNUNET_free_non_null (handle->edesc);
 560   if (NULL != handle->gns_op)
 561     GNUNET_GNS_lookup_cancel (handle->gns_op);
 562   if (NULL != handle->gns_handle)
 563     GNUNET_GNS_disconnect (handle->gns_handle);
 564
 565   if (NULL != handle->namestore_handle)
 566     GNUNET_NAMESTORE_disconnect (handle->namestore_handle);
 567   if (NULL != handle->oidc)
 568   {
 569     GNUNET_free_non_null (handle->oidc->client_id);
 570     GNUNET_free_non_null (handle->oidc->login_identity);
 571     GNUNET_free_non_null (handle->oidc->nonce);
 572     GNUNET_free_non_null (handle->oidc->redirect_uri);
 573     GNUNET_free_non_null (handle->oidc->response_type);
 574     GNUNET_free_non_null (handle->oidc->scope);
 575     GNUNET_free_non_null (handle->oidc->state);
 576     json_decref (handle->oidc->response);
 577     GNUNET_free (handle->oidc);
 578   }
 579   GNUNET_RECLAIM_attribute_list_destroy (handle->attr_list);
 580   GNUNET_RECLAIM_attestation_list_destroy (handle->attests_list);
 581
 582   for (ego_entry = handle->ego_head; NULL != ego_entry;)
 583   {
 584     ego_tmp = ego_entry;
 585     ego_entry = ego_entry->next;
 586     GNUNET_free (ego_tmp->identifier);
 587     GNUNET_free (ego_tmp->keystring);
 588     GNUNET_free (ego_tmp);
 589   }
 590   GNUNET_free (handle);
 591 }
 592
 593
 594 static void
 595 cleanup_handle_delayed (void *cls)
 596 {
 597   cleanup_handle (cls);
 598 }
 599
 600
 601 /**
 602  * Task run on error, sends error message.  Cleans up everything.
 603  *
 604  * @param cls the `struct RequestHandle`
 605  */
 606 static void
 607 do_error (void *cls)
 608 {
 609   struct RequestHandle *handle = cls;
 610   struct MHD_Response *resp;
 611   char *json_error;
 612
 613   GNUNET_asprintf (&json_error,
 614                    "{ \"error\" : \"%s\", \"error_description\" : \"%s\"%s%s%s}",
 615                    handle->emsg,
 616                    (NULL != handle->edesc) ? handle->edesc : "",
 617                    (NULL != handle->oidc->state) ? ", \"state\":\"" : "",
 618                    (NULL != handle->oidc->state) ? handle->oidc->state : "",
 619                    (NULL != handle->oidc->state) ? "\"" : "");
 620   if (0 == handle->response_code)
 621     handle->response_code = MHD_HTTP_BAD_REQUEST;
 622   resp = GNUNET_REST_create_response (json_error);
 623   if (MHD_HTTP_UNAUTHORIZED == handle->response_code)
 624     MHD_add_response_header (resp, MHD_HTTP_HEADER_WWW_AUTHENTICATE, "Basic");
 625   MHD_add_response_header (resp,
 626                            MHD_HTTP_HEADER_CONTENT_TYPE,
 627                            "application/json");
 628   handle->proc (handle->proc_cls, resp, handle->response_code);
 629   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
 630   GNUNET_free (json_error);
 631 }
 632
 633
 634 /**
 635  * Task run on error in userinfo endpoint, sends error header. Cleans up
 636  * everything
 637  *
 638  * @param cls the `struct RequestHandle`
 639  */
 640 static void
 641 do_userinfo_error (void *cls)
 642 {
 643   struct RequestHandle *handle = cls;
 644   struct MHD_Response *resp;
 645   char *error;
 646
 647   GNUNET_asprintf (&error,
 648                    "error=\"%s\", error_description=\"%s\"",
 649                    handle->emsg,
 650                    (NULL != handle->edesc) ? handle->edesc : "");
 651   resp = GNUNET_REST_create_response ("");
 652   MHD_add_response_header (resp, MHD_HTTP_HEADER_WWW_AUTHENTICATE, "Bearer");
 653   handle->proc (handle->proc_cls, resp, handle->response_code);
 654   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
 655   GNUNET_free (error);
 656 }
 657
 658
 659 /**
 660  * Task run on error, sends error message and redirects. Cleans up everything.
 661  *
 662  * @param cls the `struct RequestHandle`
 663  */
 664 static void
 665 do_redirect_error (void *cls)
 666 {
 667   struct RequestHandle *handle = cls;
 668   struct MHD_Response *resp;
 669   char *redirect;
 670
 671   GNUNET_asprintf (&redirect,
 672                    "%s?error=%s&error_description=%s%s%s",
 673                    handle->oidc->redirect_uri,
 674                    handle->emsg,
 675                    handle->edesc,
 676                    (NULL != handle->oidc->state) ? "&state=" : "",
 677                    (NULL != handle->oidc->state) ? handle->oidc->state : "");
 678   resp = GNUNET_REST_create_response ("");
 679   MHD_add_response_header (resp, "Location", redirect);
 680   handle->proc (handle->proc_cls, resp, MHD_HTTP_FOUND);
 681   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
 682   GNUNET_free (redirect);
 683 }
 684
 685
 686 /**
 687  * Task run on timeout, sends error message.  Cleans up everything.
 688  *
 689  * @param cls the `struct RequestHandle`
 690  */
 691 static void
 692 do_timeout (void *cls)
 693 {
 694   struct RequestHandle *handle = cls;
 695
 696   handle->timeout_task = NULL;
 697   do_error (handle);
 698 }
 699
 700
 701 /**
 702  * Return attributes for claim
 703  *
 704  * @param cls the request handle
 705  */
 706 static void
 707 return_userinfo_response (void *cls)
 708 {
 709   char *result_str;
 710   struct RequestHandle *handle = cls;
 711   struct MHD_Response *resp;
 712
 713   result_str = json_dumps (handle->oidc->response, 0);
 714   GNUNET_log (GNUNET_ERROR_TYPE_ERROR,"ID-Token: %s\n",result_str);
 715   resp = GNUNET_REST_create_response (result_str);
 716   handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
 717   GNUNET_free (result_str);
 718   cleanup_handle (handle);
 719 }
 720
 721
 722 /**
 723  * Respond to OPTIONS request
 724  *
 725  * @param con_handle the connection handle
 726  * @param url the url
 727  * @param cls the RequestHandle
 728  */
 729 static void
 730 options_cont (struct GNUNET_REST_RequestHandle *con_handle,
 731               const char *url,
 732               void *cls)
 733 {
 734   struct MHD_Response *resp;
 735   struct RequestHandle *handle = cls;
 736
 737   // For now, independent of path return all options
 738   resp = GNUNET_REST_create_response (NULL);
 739   MHD_add_response_header (resp, "Access-Control-Allow-Methods", allow_methods);
 740   handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
 741   cleanup_handle (handle);
 742   return;
 743 }
 744
 745
 746 /**
 747  * Interprets cookie header and pass its identity keystring to handle
 748  */
 749 static void
 750 cookie_identity_interpretation (struct RequestHandle *handle)
 751 {
 752   struct GNUNET_HashCode cache_key;
 753   char *cookies;
 754   struct GNUNET_TIME_Absolute current_time, *relog_time;
 755   char delimiter[] = "; ";
 756   char *tmp_cookies;
 757   char *token;
 758   char *value;
 759
 760   // gets identity of login try with cookie
 761   GNUNET_CRYPTO_hash (OIDC_COOKIE_HEADER_KEY,
 762                       strlen (OIDC_COOKIE_HEADER_KEY),
 763                       &cache_key);
 764   if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle
 765                                                            ->header_param_map,
 766                                                            &cache_key))
 767   {
 768     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "No cookie found\n");
 769     return;
 770   }
 771   // splits cookies and find 'Identity' cookie
 772   tmp_cookies =
 773     GNUNET_CONTAINER_multihashmap_get (handle->rest_handle->header_param_map,
 774                                        &cache_key);
 775   cookies = GNUNET_strdup (tmp_cookies);
 776   token = strtok (cookies, delimiter);
 777   handle->oidc->user_cancelled = GNUNET_NO;
 778   handle->oidc->login_identity = NULL;
 779   if (NULL == token)
 780   {
 781     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 782                 "Unable to parse cookie: %s\n",
 783                 cookies);
 784     GNUNET_free (cookies);
 785     return;
 786   }
 787
 788   while (NULL != token)
 789   {
 790     if (0 == strcmp (token, OIDC_COOKIE_HEADER_ACCESS_DENIED))
 791     {
 792       handle->oidc->user_cancelled = GNUNET_YES;
 793       GNUNET_free (cookies);
 794       return;
 795     }
 796     if (NULL != strstr (token, OIDC_COOKIE_HEADER_INFORMATION_KEY))
 797       break;
 798     token = strtok (NULL, delimiter);
 799   }
 800   if (NULL == token)
 801   {
 802     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 803                 "No cookie value to process: %s\n",
 804                 cookies);
 805     GNUNET_free (cookies);
 806     return;
 807   }
 808   GNUNET_CRYPTO_hash (token, strlen (token), &cache_key);
 809   if (GNUNET_NO ==
 810       GNUNET_CONTAINER_multihashmap_contains (OIDC_cookie_jar_map, &cache_key))
 811   {
 812     GNUNET_log (
 813       GNUNET_ERROR_TYPE_WARNING,
 814       "Found cookie `%s', but no corresponding expiration entry present...\n",
 815       token);
 816     GNUNET_free (cookies);
 817     return;
 818   }
 819   relog_time =
 820     GNUNET_CONTAINER_multihashmap_get (OIDC_cookie_jar_map, &cache_key);
 821   current_time = GNUNET_TIME_absolute_get ();
 822   // 30 min after old login -> redirect to login
 823   if (current_time.abs_value_us > relog_time->abs_value_us)
 824   {
 825     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
 826                 "Found cookie `%s', but it is expired.\n",
 827                 token);
 828     GNUNET_free (cookies);
 829     return;
 830   }
 831   value = strtok (token, OIDC_COOKIE_HEADER_INFORMATION_KEY);
 832   GNUNET_assert (NULL != value);
 833   handle->oidc->login_identity = GNUNET_strdup (value);
 834   GNUNET_free (cookies);
 835 }
 836
 837
 838 /**
 839  * Redirects to login page stored in configuration file
 840  */
 841 static void
 842 login_redirect (void *cls)
 843 {
 844   char *login_base_url;
 845   char *new_redirect;
 846   struct MHD_Response *resp;
 847   struct RequestHandle *handle = cls;
 848
 849   if (GNUNET_OK == GNUNET_CONFIGURATION_get_value_string (cfg,
 850                                                           "reclaim-rest-plugin",
 851                                                           "address",
 852                                                           &login_base_url))
 853   {
 854     GNUNET_asprintf (&new_redirect,
 855                      "%s?%s=%s&%s=%s&%s=%s&%s=%s&%s=%s&%s=%s&%s=%s&%s=%s",
 856                      login_base_url,
 857                      OIDC_RESPONSE_TYPE_KEY,
 858                      handle->oidc->response_type,
 859                      OIDC_CLIENT_ID_KEY,
 860                      handle->oidc->client_id,
 861                      OIDC_REDIRECT_URI_KEY,
 862                      handle->oidc->redirect_uri,
 863                      OIDC_SCOPE_KEY,
 864                      handle->oidc->scope,
 865                      OIDC_STATE_KEY,
 866                      (NULL != handle->oidc->state) ? handle->oidc->state : "",
 867                      OIDC_CODE_CHALLENGE_KEY,
 868                      (NULL != handle->oidc->code_challenge) ?
 869                      handle->oidc->code_challenge : "",
 870                      OIDC_NONCE_KEY,
 871                      (NULL != handle->oidc->nonce) ? handle->oidc->nonce : "",
 872                      OIDC_CLAIMS_KEY,
 873                      (NULL != handle->oidc->claims) ? handle->oidc->claims :
 874                      "");
 875     resp = GNUNET_REST_create_response ("");
 876     MHD_add_response_header (resp, "Location", new_redirect);
 877     GNUNET_free (login_base_url);
 878   }
 879   else
 880   {
 881     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
 882     handle->edesc = GNUNET_strdup ("gnunet configuration failed");
 883     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
 884     GNUNET_SCHEDULER_add_now (&do_error, handle);
 885     return;
 886   }
 887   handle->proc (handle->proc_cls, resp, MHD_HTTP_FOUND);
 888   GNUNET_free (new_redirect);
 889   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
 890 }
 891
 892
 893 /**
 894  * Does internal server error when iteration failed.
 895  */
 896 static void
 897 oidc_iteration_error (void *cls)
 898 {
 899   struct RequestHandle *handle = cls;
 900
 901   handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
 902   handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
 903   GNUNET_SCHEDULER_add_now (&do_error, handle);
 904 }
 905
 906
 907 /**
 908  * Issues ticket and redirects to relying party with the authorization code as
 909  * parameter. Otherwise redirects with error
 910  */
 911 static void
 912 oidc_ticket_issue_cb (void *cls, const struct GNUNET_RECLAIM_Ticket *ticket)
 913 {
 914   struct RequestHandle *handle = cls;
 915   struct MHD_Response *resp;
 916   char *ticket_str;
 917   char *redirect_uri;
 918   char *code_string;
 919
 920   handle->idp_op = NULL;
 921   if (NULL == ticket)
 922   {
 923     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
 924     handle->edesc = GNUNET_strdup ("Server cannot generate ticket.");
 925     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
 926     return;
 927   }
 928   handle->ticket = *ticket;
 929   ticket_str =
 930     GNUNET_STRINGS_data_to_string_alloc (&handle->ticket,
 931                                          sizeof(struct GNUNET_RECLAIM_Ticket));
 932   // TODO change if more attributes are needed (see max_age)
 933   code_string = OIDC_build_authz_code (&handle->priv_key,
 934                                        &handle->ticket,
 935                                        handle->attr_list,
 936                                        handle->attests_list,
 937                                        handle->oidc->nonce,
 938                                        handle->oidc->code_challenge);
 939   if ((NULL != handle->redirect_prefix) && (NULL != handle->redirect_suffix) &&
 940       (NULL != handle->tld))
 941   {
 942     GNUNET_asprintf (&redirect_uri,
 943                      "%s.%s/%s?%s=%s&state=%s",
 944                      handle->redirect_prefix,
 945                      handle->tld,
 946                      handle->redirect_suffix,
 947                      handle->oidc->response_type,
 948                      code_string,
 949                      handle->oidc->state);
 950   }
 951   else
 952   {
 953     GNUNET_asprintf (&redirect_uri,
 954                      "%s?%s=%s&state=%s",
 955                      handle->oidc->redirect_uri,
 956                      handle->oidc->response_type,
 957                      code_string,
 958                      handle->oidc->state);
 959   }
 960   resp = GNUNET_REST_create_response ("");
 961   MHD_add_response_header (resp, "Location", redirect_uri);
 962   handle->proc (handle->proc_cls, resp, MHD_HTTP_FOUND);
 963   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
 964   GNUNET_free (redirect_uri);
 965   GNUNET_free (ticket_str);
 966   GNUNET_free (code_string);
 967 }
 968
 969
 970 static void
 971 oidc_attest_collect_finished_cb (void *cls)
 972 {
 973   struct RequestHandle *handle = cls;
 974
 975   handle->attest_it = NULL;
 976   handle->idp_op = GNUNET_RECLAIM_ticket_issue (handle->idp,
 977                                                 &handle->priv_key,
 978                                                 &handle->oidc->client_pkey,
 979                                                 handle->attr_list,
 980                                                 &oidc_ticket_issue_cb,
 981                                                 handle);
 982 }
 983
 984
 985 /**
 986  * Collects all attributes for an ego if in scope parameter
 987  */
 988 static void
 989 oidc_attest_collect (void *cls,
 990                      const struct GNUNET_CRYPTO_EcdsaPublicKey *identity,
 991                      const struct GNUNET_RECLAIM_Attestation *attest)
 992 {
 993   struct RequestHandle *handle = cls;
 994   struct GNUNET_RECLAIM_AttributeListEntry *le;
 995
 996   for (le = handle->attr_list->list_head; NULL != le; le = le->next)
 997   {
 998     if (GNUNET_NO == GNUNET_RECLAIM_id_is_equal (&le->attribute->attestation,
 999                                                  &attest->id))
1000     {
1001       struct GNUNET_RECLAIM_AttestationListEntry *ale;
1002       ale = GNUNET_new (struct GNUNET_RECLAIM_AttestationListEntry);
1003       ale->attestation = GNUNET_RECLAIM_attestation_new (attest->name,
1004                                                          attest->type,
1005                                                          attest->data,
1006                                                          attest->data_size);
1007       GNUNET_CONTAINER_DLL_insert (handle->attests_list->list_head,
1008                                    handle->attests_list->list_tail,
1009                                    ale);
1010     }
1011   }
1012   GNUNET_RECLAIM_get_attestations_next (handle->attest_it);
1013 }
1014
1015
1016 static void
1017 oidc_attr_collect_finished_cb (void *cls)
1018 {
1019   struct RequestHandle *handle = cls;
1020
1021   handle->attr_it = NULL;
1022   handle->ticket_it = NULL;
1023   if (NULL == handle->attr_list->list_head)
1024   {
1025     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_SCOPE);
1026     handle->edesc = GNUNET_strdup ("The requested scope is not available.");
1027     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1028     return;
1029   }
1030   handle->attests_list = GNUNET_new (struct GNUNET_RECLAIM_AttestationList);
1031   handle->attest_it =
1032     GNUNET_RECLAIM_get_attestations_start (handle->idp,
1033                                            &handle->priv_key,
1034                                            &oidc_iteration_error,
1035                                            handle,
1036                                            &oidc_attest_collect,
1037                                            handle,
1038                                            &oidc_attest_collect_finished_cb,
1039                                            handle);
1040
1041   handle->idp_op = GNUNET_RECLAIM_ticket_issue (handle->idp,
1042                                                 &handle->priv_key,
1043                                                 &handle->oidc->client_pkey,
1044                                                 handle->attr_list,
1045                                                 &oidc_ticket_issue_cb,
1046                                                 handle);
1047 }
1048
1049
1050 /**
1051  * Collects all attributes for an ego if in scope parameter
1052  */
1053 static void
1054 oidc_attr_collect (void *cls,
1055                    const struct GNUNET_CRYPTO_EcdsaPublicKey *identity,
1056                    const struct GNUNET_RECLAIM_Attribute *attr)
1057 {
1058   struct RequestHandle *handle = cls;
1059   struct GNUNET_RECLAIM_AttributeListEntry *le;
1060   char *scope_variables;
1061   char *scope_variable;
1062   char delimiter[] = " ";
1063
1064   scope_variables = GNUNET_strdup (handle->oidc->scope);
1065   scope_variable = strtok (scope_variables, delimiter);
1066   while (NULL != scope_variable)
1067   {
1068     if (0 == strcmp (attr->name, scope_variable))
1069       break;
1070     scope_variable = strtok (NULL, delimiter);
1071   }
1072   if (NULL == scope_variable)
1073   {
1074     GNUNET_RECLAIM_get_attributes_next (handle->attr_it);
1075     GNUNET_free (scope_variables);
1076     // We can ignore this
1077     return;
1078   }
1079   GNUNET_free (scope_variables);
1080   le = GNUNET_new (struct GNUNET_RECLAIM_AttributeListEntry);
1081   le->attribute = GNUNET_RECLAIM_attribute_new (attr->name,
1082                                                 &attr->attestation,
1083                                                 attr->type,
1084                                                 attr->data,
1085                                                 attr->data_size);
1086   le->attribute->id = attr->id;
1087   le->attribute->flag = attr->flag;
1088   le->attribute->attestation = attr->attestation;
1089   GNUNET_CONTAINER_DLL_insert (handle->attr_list->list_head,
1090                                handle->attr_list->list_tail,
1091                                le);
1092   GNUNET_RECLAIM_get_attributes_next (handle->attr_it);
1093 }
1094
1095
1096 /**
1097  * Checks time and cookie and redirects accordingly
1098  */
1099 static void
1100 code_redirect (void *cls)
1101 {
1102   struct RequestHandle *handle = cls;
1103   struct GNUNET_TIME_Absolute current_time;
1104   struct GNUNET_TIME_Absolute *relog_time;
1105   struct GNUNET_CRYPTO_EcdsaPublicKey pubkey;
1106   struct GNUNET_CRYPTO_EcdsaPublicKey ego_pkey;
1107   struct GNUNET_HashCode cache_key;
1108   char *identity_cookie;
1109
1110   GNUNET_asprintf (&identity_cookie,
1111                    "Identity=%s",
1112                    handle->oidc->login_identity);
1113   GNUNET_CRYPTO_hash (identity_cookie, strlen (identity_cookie), &cache_key);
1114   GNUNET_free (identity_cookie);
1115   // No login time for identity -> redirect to login
1116   if (GNUNET_YES ==
1117       GNUNET_CONTAINER_multihashmap_contains (OIDC_cookie_jar_map, &cache_key))
1118   {
1119     relog_time =
1120       GNUNET_CONTAINER_multihashmap_get (OIDC_cookie_jar_map, &cache_key);
1121     current_time = GNUNET_TIME_absolute_get ();
1122     // 30 min after old login -> redirect to login
1123     if (current_time.abs_value_us <= relog_time->abs_value_us)
1124     {
1125       if (GNUNET_OK !=
1126           GNUNET_CRYPTO_ecdsa_public_key_from_string (handle->oidc
1127                                                       ->login_identity,
1128                                                       strlen (
1129                                                         handle->oidc
1130                                                         ->login_identity),
1131                                                       &pubkey))
1132       {
1133         handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_COOKIE);
1134         handle->edesc =
1135           GNUNET_strdup ("The cookie of a login identity is not valid");
1136         GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1137         return;
1138       }
1139       // iterate over egos and compare their public key
1140       for (handle->ego_entry = handle->ego_head; NULL != handle->ego_entry;
1141            handle->ego_entry = handle->ego_entry->next)
1142       {
1143         GNUNET_IDENTITY_ego_get_public_key (handle->ego_entry->ego, &ego_pkey);
1144         if (0 == GNUNET_memcmp (&ego_pkey, &pubkey))
1145         {
1146           handle->priv_key =
1147             *GNUNET_IDENTITY_ego_get_private_key (handle->ego_entry->ego);
1148           handle->idp = GNUNET_RECLAIM_connect (cfg);
1149           handle->attr_list =
1150             GNUNET_new (struct GNUNET_RECLAIM_AttributeList);
1151           handle->attr_it =
1152             GNUNET_RECLAIM_get_attributes_start (handle->idp,
1153                                                  &handle->priv_key,
1154                                                  &oidc_iteration_error,
1155                                                  handle,
1156                                                  &oidc_attr_collect,
1157                                                  handle,
1158                                                  &oidc_attr_collect_finished_cb,
1159                                                  handle);
1160           return;
1161         }
1162       }
1163       GNUNET_SCHEDULER_add_now (&login_redirect, handle);
1164       return;
1165     }
1166   }
1167 }
1168
1169
1170 static void
1171 build_redirect (void *cls)
1172 {
1173   struct RequestHandle *handle = cls;
1174   struct MHD_Response *resp;
1175   char *redirect_uri;
1176
1177   if (GNUNET_YES == handle->oidc->user_cancelled)
1178   {
1179     if ((NULL != handle->redirect_prefix) &&
1180         (NULL != handle->redirect_suffix) && (NULL != handle->tld))
1181     {
1182       GNUNET_asprintf (&redirect_uri,
1183                        "%s.%s/%s?error=%s&error_description=%s&state=%s",
1184                        handle->redirect_prefix,
1185                        handle->tld,
1186                        handle->redirect_suffix,
1187                        "access_denied",
1188                        "User denied access",
1189                        handle->oidc->state);
1190     }
1191     else
1192     {
1193       GNUNET_asprintf (&redirect_uri,
1194                        "%s?error=%s&error_description=%s&state=%s",
1195                        handle->oidc->redirect_uri,
1196                        "access_denied",
1197                        "User denied access",
1198                        handle->oidc->state);
1199     }
1200     resp = GNUNET_REST_create_response ("");
1201     MHD_add_response_header (resp, "Location", redirect_uri);
1202     handle->proc (handle->proc_cls, resp, MHD_HTTP_FOUND);
1203     GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
1204     GNUNET_free (redirect_uri);
1205     return;
1206   }
1207   GNUNET_SCHEDULER_add_now (&code_redirect, handle);
1208 }
1209
1210
1211 static void
1212 lookup_redirect_uri_result (void *cls,
1213                             uint32_t rd_count,
1214                             const struct GNUNET_GNSRECORD_Data *rd)
1215 {
1216   struct RequestHandle *handle = cls;
1217   char *tmp;
1218   char *tmp_key_str;
1219   char *pos;
1220   struct GNUNET_CRYPTO_EcdsaPublicKey redirect_zone;
1221
1222   handle->gns_op = NULL;
1223   if (0 == rd_count)
1224   {
1225     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
1226     handle->edesc =
1227       GNUNET_strdup ("Server cannot generate ticket, redirect uri not found.");
1228     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1229     return;
1230   }
1231   for (int i = 0; i < rd_count; i++)
1232   {
1233     if (GNUNET_GNSRECORD_TYPE_RECLAIM_OIDC_REDIRECT != rd[i].record_type)
1234       continue;
1235     if (0 != strncmp (rd[i].data, handle->oidc->redirect_uri, rd[i].data_size))
1236       continue;
1237     tmp = GNUNET_strndup (rd[i].data, rd[i].data_size);
1238     if (NULL == strstr (tmp, handle->oidc->client_id))
1239     {
1240       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1241                   "Redirect uri %s does not contain client_id %s\n",
1242                   tmp,
1243                   handle->oidc->client_id);
1244     }
1245     else
1246     {
1247       pos = strrchr (tmp, (unsigned char) '.');
1248       if (NULL == pos)
1249       {
1250         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1251                     "Redirect uri %s contains client_id but is malformed\n",
1252                     tmp);
1253         GNUNET_free (tmp);
1254         continue;
1255       }
1256       *pos = '\0';
1257       handle->redirect_prefix = GNUNET_strdup (tmp);
1258       tmp_key_str = pos + 1;
1259       pos = strchr (tmp_key_str, (unsigned char) '/');
1260       if (NULL == pos)
1261       {
1262         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1263                     "Redirect uri %s contains client_id but is malformed\n",
1264                     tmp);
1265         GNUNET_free (tmp);
1266         continue;
1267       }
1268       *pos = '\0';
1269       handle->redirect_suffix = GNUNET_strdup (pos + 1);
1270
1271       GNUNET_STRINGS_string_to_data (tmp_key_str,
1272                                      strlen (tmp_key_str),
1273                                      &redirect_zone,
1274                                      sizeof(redirect_zone));
1275     }
1276     GNUNET_SCHEDULER_add_now (&build_redirect, handle);
1277     GNUNET_free (tmp);
1278     return;
1279   }
1280   handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
1281   handle->edesc =
1282     GNUNET_strdup ("Server cannot generate ticket, redirect uri not found.");
1283   GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1284 }
1285
1286
1287 /**
1288  * Initiate redirect back to client.
1289  */
1290 static void
1291 client_redirect (void *cls)
1292 {
1293   struct RequestHandle *handle = cls;
1294
1295   /* Lookup client redirect uri to verify request */
1296   handle->gns_op =
1297     GNUNET_GNS_lookup (handle->gns_handle,
1298                        GNUNET_GNS_EMPTY_LABEL_AT,
1299                        &handle->oidc->client_pkey,
1300                        GNUNET_GNSRECORD_TYPE_RECLAIM_OIDC_REDIRECT,
1301                        GNUNET_GNS_LO_DEFAULT,
1302                        &lookup_redirect_uri_result,
1303                        handle);
1304 }
1305
1306
1307 static char *
1308 get_url_parameter_copy (const struct RequestHandle *handle, const char *key)
1309 {
1310   struct GNUNET_HashCode hc;
1311   char *value;
1312
1313   GNUNET_CRYPTO_hash (key, strlen (key), &hc);
1314   if (GNUNET_YES != GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle
1315                                                             ->url_param_map,
1316                                                             &hc))
1317     return NULL;
1318   value =
1319     GNUNET_CONTAINER_multihashmap_get (handle->rest_handle->url_param_map, &hc);
1320   if (NULL == value)
1321     return NULL;
1322   return GNUNET_strdup (value);
1323 }
1324
1325
1326 /**
1327  * Iteration over all results finished, build final
1328  * response.
1329  *
1330  * @param cls the `struct RequestHandle`
1331  */
1332 static void
1333 build_authz_response (void *cls)
1334 {
1335   struct RequestHandle *handle = cls;
1336   struct GNUNET_HashCode cache_key;
1337
1338   char *expected_scope;
1339   char delimiter[] = " ";
1340   int number_of_ignored_parameter, iterator;
1341
1342
1343   // REQUIRED value: redirect_uri
1344   handle->oidc->redirect_uri =
1345     get_url_parameter_copy (handle, OIDC_REDIRECT_URI_KEY);
1346   if (NULL == handle->oidc->redirect_uri)
1347   {
1348     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
1349     handle->edesc = GNUNET_strdup ("missing parameter redirect_uri");
1350     GNUNET_SCHEDULER_add_now (&do_error, handle);
1351     return;
1352   }
1353
1354   // REQUIRED value: response_type
1355   handle->oidc->response_type =
1356     get_url_parameter_copy (handle, OIDC_RESPONSE_TYPE_KEY);
1357   if (NULL == handle->oidc->response_type)
1358   {
1359     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
1360     handle->edesc = GNUNET_strdup ("missing parameter response_type");
1361     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1362     return;
1363   }
1364
1365   // REQUIRED value: scope
1366   handle->oidc->scope = get_url_parameter_copy (handle, OIDC_SCOPE_KEY);
1367   if (NULL == handle->oidc->scope)
1368   {
1369     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_SCOPE);
1370     handle->edesc = GNUNET_strdup ("missing parameter scope");
1371     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1372     return;
1373   }
1374
1375   // OPTIONAL value: nonce
1376   handle->oidc->nonce = get_url_parameter_copy (handle, OIDC_NONCE_KEY);
1377
1378   // OPTIONAL value: claims
1379   handle->oidc->claims = get_url_parameter_copy (handle, OIDC_CLAIMS_KEY);
1380
1381   // TODO check other values if needed
1382   number_of_ignored_parameter =
1383     sizeof(OIDC_ignored_parameter_array) / sizeof(char *);
1384   for (iterator = 0; iterator < number_of_ignored_parameter; iterator++)
1385   {
1386     GNUNET_CRYPTO_hash (OIDC_ignored_parameter_array[iterator],
1387                         strlen (OIDC_ignored_parameter_array[iterator]),
1388                         &cache_key);
1389     if (GNUNET_YES ==
1390         GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle
1391                                                 ->url_param_map,
1392                                                 &cache_key))
1393     {
1394       handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_ACCESS_DENIED);
1395       GNUNET_asprintf (&handle->edesc,
1396                        "Server will not handle parameter: %s",
1397                        OIDC_ignored_parameter_array[iterator]);
1398       GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1399       return;
1400     }
1401   }
1402
1403   // We only support authorization code flows.
1404   if (0 != strcmp (handle->oidc->response_type,
1405                    OIDC_EXPECTED_AUTHORIZATION_RESPONSE_TYPE))
1406   {
1407     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_UNSUPPORTED_RESPONSE_TYPE);
1408     handle->edesc = GNUNET_strdup ("The authorization server does not support "
1409                                    "obtaining this authorization code.");
1410     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1411     return;
1412   }
1413
1414   // Checks if scope contains 'openid'
1415   expected_scope = GNUNET_strdup (handle->oidc->scope);
1416   char *test;
1417   test = strtok (expected_scope, delimiter);
1418   while (NULL != test)
1419   {
1420     if (0 == strcmp (OIDC_EXPECTED_AUTHORIZATION_SCOPE, expected_scope))
1421       break;
1422     test = strtok (NULL, delimiter);
1423   }
1424   if (NULL == test)
1425   {
1426     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_SCOPE);
1427     handle->edesc =
1428       GNUNET_strdup ("The requested scope is invalid, unknown, or malformed.");
1429     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
1430     GNUNET_free (expected_scope);
1431     return;
1432   }
1433
1434   GNUNET_free (expected_scope);
1435   if ((NULL == handle->oidc->login_identity) &&
1436       (GNUNET_NO == handle->oidc->user_cancelled))
1437     GNUNET_SCHEDULER_add_now (&login_redirect, handle);
1438   else
1439     GNUNET_SCHEDULER_add_now (&client_redirect, handle);
1440 }
1441
1442
1443 /**
1444  * Iterate over tlds in config
1445  */
1446 static void
1447 tld_iter (void *cls, const char *section, const char *option, const char *value)
1448 {
1449   struct RequestHandle *handle = cls;
1450   struct GNUNET_CRYPTO_EcdsaPublicKey pkey;
1451
1452   if (GNUNET_OK !=
1453       GNUNET_CRYPTO_ecdsa_public_key_from_string (value, strlen (value), &pkey))
1454   {
1455     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Skipping non key %s\n", value);
1456     return;
1457   }
1458   if (0 == GNUNET_memcmp (&pkey, &handle->oidc->client_pkey))
1459     handle->tld = GNUNET_strdup (option + 1);
1460 }
1461
1462
1463 /**
1464  * Responds to authorization GET and url-encoded POST request
1465  *
1466  * @param con_handle the connection handle
1467  * @param url the url
1468  * @param cls the RequestHandle
1469  */
1470 static void
1471 authorize_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
1472                     const char *url,
1473                     void *cls)
1474 {
1475   struct RequestHandle *handle = cls;
1476   struct EgoEntry *tmp_ego;
1477   const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv_key;
1478   struct GNUNET_CRYPTO_EcdsaPublicKey pkey;
1479
1480   cookie_identity_interpretation (handle);
1481
1482   // RECOMMENDED value: state - REQUIRED for answers
1483   handle->oidc->state = get_url_parameter_copy (handle, OIDC_STATE_KEY);
1484
1485   // REQUIRED value: client_id
1486   handle->oidc->client_id = get_url_parameter_copy (handle, OIDC_CLIENT_ID_KEY);
1487   if (NULL == handle->oidc->client_id)
1488   {
1489     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
1490     handle->edesc = GNUNET_strdup ("missing parameter client_id");
1491     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
1492     GNUNET_SCHEDULER_add_now (&do_error, handle);
1493     return;
1494   }
1495
1496   // OPTIONAL value: code_challenge
1497   handle->oidc->code_challenge = get_url_parameter_copy (handle,
1498                                                          OIDC_CODE_CHALLENGE_KEY);
1499   if (NULL == handle->oidc->code_challenge)
1500   {
1501     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1502                 "OAuth authorization request does not contain PKCE parameters!\n");
1503   }
1504
1505   if (GNUNET_OK !=
1506       GNUNET_CRYPTO_ecdsa_public_key_from_string (handle->oidc->client_id,
1507                                                   strlen (
1508                                                     handle->oidc->client_id),
1509                                                   &handle->oidc->client_pkey))
1510   {
1511     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_UNAUTHORIZED_CLIENT);
1512     handle->edesc = GNUNET_strdup ("The client is not authorized to request an "
1513                                    "authorization code using this method.");
1514     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
1515     GNUNET_SCHEDULER_add_now (&do_error, handle);
1516     return;
1517   }
1518
1519   // If we know this identity, translated the corresponding TLD
1520   // TODO: We might want to have a reverse lookup functionality for TLDs?
1521   for (tmp_ego = handle->ego_head; NULL != tmp_ego; tmp_ego = tmp_ego->next)
1522   {
1523     priv_key = GNUNET_IDENTITY_ego_get_private_key (tmp_ego->ego);
1524     GNUNET_CRYPTO_ecdsa_key_get_public (priv_key, &pkey);
1525     if (0 == GNUNET_memcmp (&pkey, &handle->oidc->client_pkey))
1526     {
1527       handle->tld = GNUNET_strdup (tmp_ego->identifier);
1528       handle->ego_entry = handle->ego_tail;
1529     }
1530   }
1531   handle->oidc->scope = get_url_parameter_copy (handle, OIDC_SCOPE_KEY);
1532   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Scope: %s\n",GNUNET_strdup (
1533                 handle->oidc->scope));
1534   if (NULL == handle->tld)
1535     GNUNET_CONFIGURATION_iterate_section_values (cfg, "gns", tld_iter, handle);
1536   if (NULL == handle->tld)
1537     handle->tld = GNUNET_strdup (handle->oidc->client_id);
1538   GNUNET_SCHEDULER_add_now (&build_authz_response, handle);
1539 }
1540
1541
1542 /**
1543  * Combines an identity with a login time and responds OK to login request
1544  *
1545  * @param con_handle the connection handle
1546  * @param url the url
1547  * @param cls the RequestHandle
1548  */
1549 static void
1550 login_cont (struct GNUNET_REST_RequestHandle *con_handle,
1551             const char *url,
1552             void *cls)
1553 {
1554   struct MHD_Response *resp = GNUNET_REST_create_response ("");
1555   struct RequestHandle *handle = cls;
1556   struct GNUNET_HashCode cache_key;
1557   struct GNUNET_TIME_Absolute *current_time;
1558   struct GNUNET_TIME_Absolute *last_time;
1559   char *cookie;
1560   char *header_val;
1561   json_t *root;
1562   json_error_t error;
1563   json_t *identity;
1564   char term_data[handle->rest_handle->data_size + 1];
1565
1566   term_data[handle->rest_handle->data_size] = '\0';
1567   GNUNET_memcpy (term_data,
1568                  handle->rest_handle->data,
1569                  handle->rest_handle->data_size);
1570   root = json_loads (term_data, JSON_DECODE_ANY, &error);
1571   identity = json_object_get (root, "identity");
1572   if (! json_is_string (identity))
1573   {
1574     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1575                 "Error parsing json string from %s\n",
1576                 term_data);
1577     handle->proc (handle->proc_cls, resp, MHD_HTTP_BAD_REQUEST);
1578     json_decref (root);
1579     GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
1580     return;
1581   }
1582   GNUNET_asprintf (&cookie, "Identity=%s", json_string_value (identity));
1583   GNUNET_asprintf (&header_val,
1584                    "%s;Max-Age=%d",
1585                    cookie,
1586                    OIDC_COOKIE_EXPIRATION);
1587   MHD_add_response_header (resp, "Set-Cookie", header_val);
1588   MHD_add_response_header (resp, "Access-Control-Allow-Methods", "POST");
1589   GNUNET_CRYPTO_hash (cookie, strlen (cookie), &cache_key);
1590
1591   if (0 != strcmp (json_string_value (identity), "Denied"))
1592   {
1593     current_time = GNUNET_new (struct GNUNET_TIME_Absolute);
1594     *current_time = GNUNET_TIME_relative_to_absolute (
1595       GNUNET_TIME_relative_multiply (GNUNET_TIME_relative_get_second_ (),
1596                                      OIDC_COOKIE_EXPIRATION));
1597     last_time =
1598       GNUNET_CONTAINER_multihashmap_get (OIDC_cookie_jar_map, &cache_key);
1599     GNUNET_free_non_null (last_time);
1600     GNUNET_CONTAINER_multihashmap_put (OIDC_cookie_jar_map,
1601                                        &cache_key,
1602                                        current_time,
1603                                        GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE);
1604   }
1605   handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
1606   GNUNET_free (cookie);
1607   GNUNET_free (header_val);
1608   json_decref (root);
1609   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
1610 }
1611
1612
1613 static int
1614 check_authorization (struct RequestHandle *handle,
1615                      struct GNUNET_CRYPTO_EcdsaPublicKey *cid)
1616 {
1617   struct GNUNET_HashCode cache_key;
1618   char *authorization;
1619   char *credentials;
1620   char *basic_authorization;
1621   char *client_id;
1622   char *pass;
1623   char *expected_pass;
1624
1625   GNUNET_CRYPTO_hash (OIDC_AUTHORIZATION_HEADER_KEY,
1626                       strlen (OIDC_AUTHORIZATION_HEADER_KEY),
1627                       &cache_key);
1628   if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle
1629                                                            ->header_param_map,
1630                                                            &cache_key))
1631   {
1632     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
1633     handle->edesc = GNUNET_strdup ("missing authorization");
1634     handle->response_code = MHD_HTTP_UNAUTHORIZED;
1635     return GNUNET_SYSERR;
1636   }
1637   authorization =
1638     GNUNET_CONTAINER_multihashmap_get (handle->rest_handle->header_param_map,
1639                                        &cache_key);
1640
1641   // split header in "Basic" and [content]
1642   credentials = strtok (authorization, " ");
1643   if ((NULL == credentials) || (0 != strcmp ("Basic", credentials)))
1644   {
1645     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
1646     handle->response_code = MHD_HTTP_UNAUTHORIZED;
1647     return GNUNET_SYSERR;
1648   }
1649   credentials = strtok (NULL, " ");
1650   if (NULL == credentials)
1651   {
1652     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
1653     handle->response_code = MHD_HTTP_UNAUTHORIZED;
1654     return GNUNET_SYSERR;
1655   }
1656   GNUNET_STRINGS_base64_decode (credentials,
1657                                 strlen (credentials),
1658                                 (void **) &basic_authorization);
1659
1660   if (NULL == basic_authorization)
1661   {
1662     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
1663     handle->response_code = MHD_HTTP_UNAUTHORIZED;
1664     return GNUNET_SYSERR;
1665   }
1666   client_id = strtok (basic_authorization, ":");
1667   if (NULL == client_id)
1668   {
1669     GNUNET_free_non_null (basic_authorization);
1670     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
1671     handle->response_code = MHD_HTTP_UNAUTHORIZED;
1672     return GNUNET_SYSERR;
1673   }
1674   pass = strtok (NULL, ":");
1675   if (NULL == pass)
1676   {
1677     GNUNET_free_non_null (basic_authorization);
1678     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
1679     handle->response_code = MHD_HTTP_UNAUTHORIZED;
1680     return GNUNET_SYSERR;
1681   }
1682
1683   // check client password
1684   if (GNUNET_OK == GNUNET_CONFIGURATION_get_value_string (cfg,
1685                                                           "reclaim-rest-plugin",
1686                                                           "OIDC_CLIENT_SECRET",
1687                                                           &expected_pass))
1688   {
1689     if (0 != strcmp (expected_pass, pass))
1690     {
1691       GNUNET_free_non_null (basic_authorization);
1692       GNUNET_free (expected_pass);
1693       handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
1694       handle->response_code = MHD_HTTP_UNAUTHORIZED;
1695       return GNUNET_SYSERR;
1696     }
1697     GNUNET_free (expected_pass);
1698   }
1699   else
1700   {
1701     GNUNET_free_non_null (basic_authorization);
1702     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
1703     handle->edesc = GNUNET_strdup ("gnunet configuration failed");
1704     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
1705     return GNUNET_SYSERR;
1706   }
1707
1708   // check client_id
1709   for (handle->ego_entry = handle->ego_head; NULL != handle->ego_entry;
1710        handle->ego_entry = handle->ego_entry->next)
1711   {
1712     if (0 == strcmp (handle->ego_entry->keystring, client_id))
1713       break;
1714   }
1715   if (NULL == handle->ego_entry)
1716   {
1717     GNUNET_free_non_null (basic_authorization);
1718     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
1719     handle->response_code = MHD_HTTP_UNAUTHORIZED;
1720     return GNUNET_SYSERR;
1721   }
1722   GNUNET_STRINGS_string_to_data (client_id,
1723                                  strlen (client_id),
1724                                  cid,
1725                                  sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey));
1726
1727   GNUNET_free (basic_authorization);
1728   return GNUNET_OK;
1729 }
1730
1731
1732 const struct EgoEntry *
1733 find_ego (struct RequestHandle *handle,
1734           struct GNUNET_CRYPTO_EcdsaPublicKey *test_key)
1735 {
1736   struct EgoEntry *ego_entry;
1737   struct GNUNET_CRYPTO_EcdsaPublicKey pub_key;
1738
1739   for (ego_entry = handle->ego_head; NULL != ego_entry;
1740        ego_entry = ego_entry->next)
1741   {
1742     GNUNET_IDENTITY_ego_get_public_key (ego_entry->ego, &pub_key);
1743     if (0 == GNUNET_memcmp (&pub_key, test_key))
1744       return ego_entry;
1745   }
1746   return NULL;
1747 }
1748
1749
1750 static void
1751 persist_access_token (const struct RequestHandle *handle,
1752                       const char *access_token,
1753                       const struct GNUNET_RECLAIM_Ticket *ticket)
1754 {
1755   struct GNUNET_HashCode hc;
1756   struct GNUNET_RECLAIM_Ticket *ticketbuf;
1757
1758   GNUNET_CRYPTO_hash (access_token, strlen (access_token), &hc);
1759   ticketbuf = GNUNET_new (struct GNUNET_RECLAIM_Ticket);
1760   *ticketbuf = *ticket;
1761   GNUNET_assert (GNUNET_SYSERR !=
1762                  GNUNET_CONTAINER_multihashmap_put (
1763                    OIDC_access_token_map,
1764                    &hc,
1765                    ticketbuf,
1766                    GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1767 }
1768
1769
1770 /**
1771  * Responds to token url-encoded POST request
1772  *
1773  * @param con_handle the connection handle
1774  * @param url the url
1775  * @param cls the RequestHandle
1776  */
1777 static void
1778 token_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
1779                 const char *url,
1780                 void *cls)
1781 {
1782   struct RequestHandle *handle = cls;
1783   const struct EgoEntry *ego_entry;
1784   struct GNUNET_TIME_Relative expiration_time;
1785   struct GNUNET_RECLAIM_AttributeList *cl;
1786   struct GNUNET_RECLAIM_AttestationList *al;
1787   struct GNUNET_RECLAIM_Ticket ticket;
1788   struct GNUNET_CRYPTO_EcdsaPublicKey cid;
1789   const struct GNUNET_CRYPTO_EcdsaPrivateKey *privkey;
1790   struct GNUNET_HashCode cache_key;
1791   struct MHD_Response *resp;
1792   char *grant_type;
1793   char *code;
1794   char *json_response;
1795   char *id_token;
1796   char *access_token;
1797   char *jwt_secret;
1798   char *nonce;
1799   char *code_verifier;
1800
1801   /*
1802    * Check Authorization
1803    */
1804   if (GNUNET_SYSERR == check_authorization (handle, &cid))
1805   {
1806     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1807                 "OIDC authorization for token endpoint failed\n");
1808     GNUNET_SCHEDULER_add_now (&do_error, handle);
1809     return;
1810   }
1811
1812   /*
1813    * Check parameter
1814    */
1815
1816   // TODO Do not allow multiple equal parameter names
1817   // REQUIRED grant_type
1818   GNUNET_CRYPTO_hash (OIDC_GRANT_TYPE_KEY,
1819                       strlen (OIDC_GRANT_TYPE_KEY),
1820                       &cache_key);
1821   grant_type = get_url_parameter_copy (handle, OIDC_GRANT_TYPE_KEY);
1822   if (NULL == grant_type)
1823   {
1824     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
1825     handle->edesc = GNUNET_strdup ("missing parameter grant_type");
1826     handle->response_code = MHD_HTTP_BAD_REQUEST;
1827     GNUNET_SCHEDULER_add_now (&do_error, handle);
1828     return;
1829   }
1830
1831   // Check parameter grant_type == "authorization_code"
1832   if (0 != strcmp (OIDC_GRANT_TYPE_VALUE, grant_type))
1833   {
1834     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_UNSUPPORTED_GRANT_TYPE);
1835     handle->response_code = MHD_HTTP_BAD_REQUEST;
1836     GNUNET_free (grant_type);
1837     GNUNET_SCHEDULER_add_now (&do_error, handle);
1838     return;
1839   }
1840   GNUNET_free (grant_type);
1841   // REQUIRED code
1842   code = get_url_parameter_copy (handle, OIDC_CODE_KEY);
1843   if (NULL == code)
1844   {
1845     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
1846     handle->edesc = GNUNET_strdup ("missing parameter code");
1847     handle->response_code = MHD_HTTP_BAD_REQUEST;
1848     GNUNET_SCHEDULER_add_now (&do_error, handle);
1849     return;
1850   }
1851   ego_entry = find_ego (handle, &cid);
1852   if (NULL == ego_entry)
1853   {
1854     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
1855     handle->edesc = GNUNET_strdup ("Unknown client");
1856     handle->response_code = MHD_HTTP_BAD_REQUEST;
1857     GNUNET_free (code);
1858     GNUNET_SCHEDULER_add_now (&do_error, handle);
1859     return;
1860   }
1861   privkey = GNUNET_IDENTITY_ego_get_private_key (ego_entry->ego);
1862
1863   // REQUIRED code verifier
1864   code_verifier = get_url_parameter_copy (handle, OIDC_CODE_VERIFIER_KEY);
1865   if (NULL == code_verifier)
1866   {
1867     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1868                 "OAuth authorization request does not contain PKCE parameters!\n");
1869
1870   }
1871
1872   // decode code
1873   if (GNUNET_OK != OIDC_parse_authz_code (privkey, code, code_verifier, &ticket,
1874                                           &cl, &al, &nonce))
1875   {
1876     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
1877     handle->edesc = GNUNET_strdup ("invalid code");
1878     handle->response_code = MHD_HTTP_BAD_REQUEST;
1879     GNUNET_free (code);
1880     GNUNET_SCHEDULER_add_now (&do_error, handle);
1881     return;
1882   }
1883   GNUNET_free (code);
1884
1885   // create jwt
1886   if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_time (cfg,
1887                                                         "reclaim-rest-plugin",
1888                                                         "expiration_time",
1889                                                         &expiration_time))
1890   {
1891     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
1892     handle->edesc = GNUNET_strdup ("gnunet configuration failed");
1893     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
1894     GNUNET_SCHEDULER_add_now (&do_error, handle);
1895     return;
1896   }
1897
1898
1899   // TODO OPTIONAL acr,amr,azp
1900   if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_string (cfg,
1901                                                           "reclaim-rest-plugin",
1902                                                           "jwt_secret",
1903                                                           &jwt_secret))
1904   {
1905     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
1906     handle->edesc = GNUNET_strdup ("No signing secret configured!");
1907     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
1908     GNUNET_SCHEDULER_add_now (&do_error, handle);
1909     return;
1910   }
1911   id_token = OIDC_id_token_new (&ticket.audience,
1912                                 &ticket.identity,
1913                                 cl,
1914                                 al,
1915                                 &expiration_time,
1916                                 (NULL != nonce) ? nonce : NULL,
1917                                 jwt_secret);
1918   access_token = OIDC_access_token_new ();
1919   OIDC_build_token_response (access_token,
1920                              id_token,
1921                              &expiration_time,
1922                              &json_response);
1923
1924   persist_access_token (handle, access_token, &ticket);
1925   resp = GNUNET_REST_create_response (json_response);
1926   MHD_add_response_header (resp, "Cache-Control", "no-store");
1927   MHD_add_response_header (resp, "Pragma", "no-cache");
1928   MHD_add_response_header (resp, "Content-Type", "application/json");
1929   handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
1930   GNUNET_RECLAIM_attribute_list_destroy (cl);
1931   GNUNET_RECLAIM_attestation_list_destroy (al);
1932   GNUNET_free (access_token);
1933   GNUNET_free (json_response);
1934   GNUNET_free (id_token);
1935   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
1936 }
1937
1938
1939 /**
1940  * Collects claims and stores them in handle
1941  */
1942 static void
1943 consume_ticket (void *cls,
1944                 const struct GNUNET_CRYPTO_EcdsaPublicKey *identity,
1945                 const struct GNUNET_RECLAIM_Attribute *attr,
1946                 const struct GNUNET_RECLAIM_Attestation *attest)
1947 {
1948   struct RequestHandle *handle = cls;
1949   if (NULL == identity)
1950   {
1951     GNUNET_SCHEDULER_add_now (&return_userinfo_response, handle);
1952     return;
1953   }
1954   if (GNUNET_YES == GNUNET_RECLAIM_id_is_zero (&attr->attestation))
1955   {
1956     char *tmp_value;
1957     json_t *value;
1958     tmp_value = GNUNET_RECLAIM_attribute_value_to_string (attr->type,
1959                                                           attr->data,
1960                                                           attr->data_size);
1961     value = json_string (tmp_value);
1962     json_object_set_new (handle->oidc->response, attr->name, value);
1963     GNUNET_free (tmp_value);
1964     return;
1965   }
1966   json_t *claim_sources;
1967   json_t *claim_sources_jwt;
1968   json_t *claim_names;
1969   char *attest_val_str;
1970   claim_sources = json_object_get (handle->oidc->response,"_claim_sources");
1971   claim_names = json_object_get (handle->oidc->response,"_claim_names");
1972   attest_val_str =
1973     GNUNET_RECLAIM_attestation_value_to_string (attest->type,
1974                                                 attest->data,
1975                                                 attest->data_size);
1976   if ((NULL == claim_sources) && (NULL == claim_names) )
1977   {
1978     claim_sources = json_object ();
1979     claim_names = json_object ();
1980   }
1981   char *source_name;
1982   int i = 0;
1983   GNUNET_asprintf (&source_name, "src%d", i);
1984   while (NULL != (claim_sources_jwt = json_object_get (claim_sources,
1985                                                        source_name)))
1986   {
1987     if (0 == strcmp (json_string_value (json_object_get (claim_sources_jwt,
1988                                                          "JWT")),
1989                      attest_val_str))
1990     {
1991       // Adapt only the claim names
1992       json_object_set_new (claim_names, attr->data,
1993                            json_string (source_name));
1994       json_object_set (handle->oidc->response,
1995                        "_claim_names", claim_names);
1996       break;
1997     }
1998     i++;
1999     GNUNET_free (source_name);
2000     GNUNET_asprintf (&source_name, "src%d", i);
2001   }
2002
2003   // Create new one
2004   if (NULL == claim_sources_jwt)
2005   {
2006     claim_sources_jwt = json_object ();
2007     // Set the JWT for names
2008     json_object_set_new (claim_names, attr->data,
2009                          json_string (source_name));
2010     // Set the JWT for the inner source
2011     json_object_set_new (claim_sources_jwt, "JWT",
2012                          json_string (attest_val_str));
2013     // Set the JWT for the source
2014     json_object_set_new (claim_sources, source_name, claim_sources_jwt);
2015     // Set as claims
2016     json_object_set (handle->oidc->response, "_claim_names", claim_names);
2017     json_object_set (handle->oidc->response, "_claim_sources",claim_sources);
2018   }
2019
2020   json_decref (claim_sources);
2021   json_decref (claim_names);
2022   json_decref (claim_sources_jwt);
2023   GNUNET_free (attest_val_str);
2024 }
2025
2026
2027 /**
2028  * Responds to userinfo GET and url-encoded POST request
2029  *
2030  * @param con_handle the connection handle
2031  * @param url the url
2032  * @param cls the RequestHandle
2033  */
2034 static void
2035 userinfo_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
2036                    const char *url,
2037                    void *cls)
2038 {
2039   // TODO expiration time
2040   struct RequestHandle *handle = cls;
2041   char delimiter[] = " ";
2042   struct GNUNET_HashCode cache_key;
2043   char *authorization;
2044   char *authorization_type;
2045   char *authorization_access_token;
2046   struct GNUNET_RECLAIM_Ticket *ticket;
2047   const struct EgoEntry *ego_entry;
2048   const struct GNUNET_CRYPTO_EcdsaPrivateKey *privkey;
2049
2050   GNUNET_CRYPTO_hash (OIDC_AUTHORIZATION_HEADER_KEY,
2051                       strlen (OIDC_AUTHORIZATION_HEADER_KEY),
2052                       &cache_key);
2053   if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle
2054                                                            ->header_param_map,
2055                                                            &cache_key))
2056   {
2057     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
2058     handle->edesc = GNUNET_strdup ("No Access Token");
2059     handle->response_code = MHD_HTTP_UNAUTHORIZED;
2060     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
2061     return;
2062   }
2063   authorization =
2064     GNUNET_CONTAINER_multihashmap_get (handle->rest_handle->header_param_map,
2065                                        &cache_key);
2066
2067   // split header in "Bearer" and access_token
2068   authorization = GNUNET_strdup (authorization);
2069   authorization_type = strtok (authorization, delimiter);
2070   if ((NULL == authorization_type) ||
2071       (0 != strcmp ("Bearer", authorization_type)))
2072   {
2073     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
2074     handle->edesc = GNUNET_strdup ("No Access Token");
2075     handle->response_code = MHD_HTTP_UNAUTHORIZED;
2076     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
2077     GNUNET_free (authorization);
2078     return;
2079   }
2080   authorization_access_token = strtok (NULL, delimiter);
2081   if (NULL == authorization_access_token)
2082   {
2083     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
2084     handle->edesc = GNUNET_strdup ("Access token missing");
2085     handle->response_code = MHD_HTTP_UNAUTHORIZED;
2086     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
2087     GNUNET_free (authorization);
2088     return;
2089   }
2090
2091   GNUNET_CRYPTO_hash (authorization_access_token,
2092                       strlen (authorization_access_token),
2093                       &cache_key);
2094   if (GNUNET_NO ==
2095       GNUNET_CONTAINER_multihashmap_contains (OIDC_access_token_map,
2096                                               &cache_key))
2097   {
2098     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
2099     handle->edesc = GNUNET_strdup ("The access token expired");
2100     handle->response_code = MHD_HTTP_UNAUTHORIZED;
2101     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
2102     GNUNET_free (authorization);
2103     return;
2104   }
2105   ticket =
2106     GNUNET_CONTAINER_multihashmap_get (OIDC_access_token_map, &cache_key);
2107   GNUNET_assert (NULL != ticket);
2108   ego_entry = find_ego (handle, &ticket->audience);
2109   if (NULL == ego_entry)
2110   {
2111     handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
2112     handle->edesc = GNUNET_strdup ("The access token expired");
2113     handle->response_code = MHD_HTTP_UNAUTHORIZED;
2114     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
2115     GNUNET_free (authorization);
2116     return;
2117   }
2118
2119   handle->idp = GNUNET_RECLAIM_connect (cfg);
2120   handle->oidc->response = json_object ();
2121   json_object_set_new (handle->oidc->response,
2122                        "sub",
2123                        json_string (ego_entry->keystring));
2124   privkey = GNUNET_IDENTITY_ego_get_private_key (ego_entry->ego);
2125   handle->idp_op = GNUNET_RECLAIM_ticket_consume (handle->idp,
2126                                                   privkey,
2127                                                   ticket,
2128                                                   consume_ticket,
2129                                                   handle);
2130   GNUNET_free (authorization);
2131 }
2132
2133
2134 /**
2135  * Handle rest request
2136  *
2137  * @param handle the request handle
2138  */
2139 static void
2140 init_cont (struct RequestHandle *handle)
2141 {
2142   struct GNUNET_REST_RequestHandlerError err;
2143   static const struct GNUNET_REST_RequestHandler handlers[] =
2144   { { MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_AUTHORIZE, &authorize_endpoint },
2145     { MHD_HTTP_METHOD_POST,
2146       GNUNET_REST_API_NS_AUTHORIZE,
2147       &authorize_endpoint },   // url-encoded
2148     { MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_LOGIN, &login_cont },
2149     { MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_TOKEN, &token_endpoint },
2150     { MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_USERINFO, &userinfo_endpoint },
2151     { MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_USERINFO, &userinfo_endpoint },
2152     { MHD_HTTP_METHOD_OPTIONS, GNUNET_REST_API_NS_OIDC, &options_cont },
2153     GNUNET_REST_HANDLER_END };
2154
2155   if (GNUNET_NO ==
2156       GNUNET_REST_handle_request (handle->rest_handle, handlers, &err, handle))
2157   {
2158     handle->response_code = err.error_code;
2159     GNUNET_SCHEDULER_add_now (&do_error, handle);
2160   }
2161 }
2162
2163
2164 /**
2165  * If listing is enabled, prints information about the egos.
2166  *
2167  * This function is initially called for all egos and then again
2168  * whenever a ego's identifier changes or if it is deleted.  At the
2169  * end of the initial pass over all egos, the function is once called
2170  * with 'NULL' for 'ego'. That does NOT mean that the callback won't
2171  * be invoked in the future or that there was an error.
2172  *
2173  * When used with 'GNUNET_IDENTITY_create' or 'GNUNET_IDENTITY_get',
2174  * this function is only called ONCE, and 'NULL' being passed in
2175  * 'ego' does indicate an error (i.e. name is taken or no default
2176  * value is known).  If 'ego' is non-NULL and if '*ctx'
2177  * is set in those callbacks, the value WILL be passed to a subsequent
2178  * call to the identity callback of 'GNUNET_IDENTITY_connect' (if
2179  * that one was not NULL).
2180  *
2181  * When an identity is renamed, this function is called with the
2182  * (known) ego but the NEW identifier.
2183  *
2184  * When an identity is deleted, this function is called with the
2185  * (known) ego and "NULL" for the 'identifier'.  In this case,
2186  * the 'ego' is henceforth invalid (and the 'ctx' should also be
2187  * cleaned up).
2188  *
2189  * @param cls closure
2190  * @param ego ego handle
2191  * @param ctx context for application to store data for this ego
2192  *                 (during the lifetime of this process, initially NULL)
2193  * @param identifier identifier assigned by the user for this ego,
2194  *                   NULL if the user just deleted the ego and it
2195  *                   must thus no longer be used
2196  */
2197 static void
2198 list_ego (void *cls,
2199           struct GNUNET_IDENTITY_Ego *ego,
2200           void **ctx,
2201           const char *identifier)
2202 {
2203   struct RequestHandle *handle = cls;
2204   struct EgoEntry *ego_entry;
2205   struct GNUNET_CRYPTO_EcdsaPublicKey pk;
2206
2207   if ((NULL == ego) && (ID_REST_STATE_INIT == handle->state))
2208   {
2209     handle->state = ID_REST_STATE_POST_INIT;
2210     init_cont (handle);
2211     return;
2212   }
2213   GNUNET_assert (NULL != ego);
2214   if (ID_REST_STATE_INIT == handle->state)
2215
2216   {
2217     ego_entry = GNUNET_new (struct EgoEntry);
2218     GNUNET_IDENTITY_ego_get_public_key (ego, &pk);
2219     ego_entry->keystring = GNUNET_CRYPTO_ecdsa_public_key_to_string (&pk);
2220     ego_entry->ego = ego;
2221     ego_entry->identifier = GNUNET_strdup (identifier);
2222     GNUNET_CONTAINER_DLL_insert_tail (handle->ego_head,
2223                                       handle->ego_tail,
2224                                       ego_entry);
2225     return;
2226   }
2227   /* Ego renamed or added */
2228   if (identifier != NULL)
2229   {
2230     for (ego_entry = handle->ego_head; NULL != ego_entry;
2231          ego_entry = ego_entry->next)
2232     {
2233       if (ego_entry->ego == ego)
2234       {
2235         /* Rename */
2236         GNUNET_free (ego_entry->identifier);
2237         ego_entry->identifier = GNUNET_strdup (identifier);
2238         break;
2239       }
2240     }
2241     if (NULL == ego_entry)
2242     {
2243       /* Add */
2244       ego_entry = GNUNET_new (struct EgoEntry);
2245       GNUNET_IDENTITY_ego_get_public_key (ego, &pk);
2246       ego_entry->keystring = GNUNET_CRYPTO_ecdsa_public_key_to_string (&pk);
2247       ego_entry->ego = ego;
2248       ego_entry->identifier = GNUNET_strdup (identifier);
2249       GNUNET_CONTAINER_DLL_insert_tail (handle->ego_head,
2250                                         handle->ego_tail,
2251                                         ego_entry);
2252     }
2253   }
2254   else
2255   {
2256     /* Delete */
2257     for (ego_entry = handle->ego_head; NULL != ego_entry;
2258          ego_entry = ego_entry->next)
2259     {
2260       if (ego_entry->ego == ego)
2261         break;
2262     }
2263     if (NULL != ego_entry)
2264       GNUNET_CONTAINER_DLL_remove (handle->ego_head,
2265                                    handle->ego_tail,
2266                                    ego_entry);
2267   }
2268 }
2269
2270
2271 static void
2272 rest_identity_process_request (struct GNUNET_REST_RequestHandle *rest_handle,
2273                                GNUNET_REST_ResultProcessor proc,
2274                                void *proc_cls)
2275 {
2276   struct RequestHandle *handle = GNUNET_new (struct RequestHandle);
2277
2278   handle->oidc = GNUNET_new (struct OIDC_Variables);
2279   if (NULL == OIDC_cookie_jar_map)
2280     OIDC_cookie_jar_map = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
2281   if (NULL == OIDC_access_token_map)
2282     OIDC_access_token_map =
2283       GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
2284   handle->response_code = 0;
2285   handle->timeout = GNUNET_TIME_UNIT_FOREVER_REL;
2286   handle->proc_cls = proc_cls;
2287   handle->proc = proc;
2288   handle->state = ID_REST_STATE_INIT;
2289   handle->rest_handle = rest_handle;
2290
2291   handle->url = GNUNET_strdup (rest_handle->url);
2292   if (handle->url[strlen (handle->url) - 1] == '/')
2293     handle->url[strlen (handle->url) - 1] = '\0';
2294   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connecting...\n");
2295   handle->identity_handle = GNUNET_IDENTITY_connect (cfg, &list_ego, handle);
2296   handle->gns_handle = GNUNET_GNS_connect (cfg);
2297   handle->namestore_handle = GNUNET_NAMESTORE_connect (cfg);
2298   handle->timeout_task =
2299     GNUNET_SCHEDULER_add_delayed (handle->timeout, &do_timeout, handle);
2300   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connected\n");
2301 }
2302
2303
2304 /**
2305  * Entry point for the plugin.
2306  *
2307  * @param cls Config info
2308  * @return NULL on error, otherwise the plugin context
2309  */
2310 void *
2311 libgnunet_plugin_rest_openid_connect_init (void *cls)
2312 {
2313   static struct Plugin plugin;
2314   struct GNUNET_REST_Plugin *api;
2315
2316   cfg = cls;
2317   if (NULL != plugin.cfg)
2318     return NULL; /* can only initialize once! */
2319   memset (&plugin, 0, sizeof(struct Plugin));
2320   plugin.cfg = cfg;
2321   api = GNUNET_new (struct GNUNET_REST_Plugin);
2322   api->cls = &plugin;
2323   api->name = GNUNET_REST_API_NS_OIDC;
2324   api->process_request = &rest_identity_process_request;
2325   GNUNET_asprintf (&allow_methods,
2326                    "%s, %s, %s, %s, %s",
2327                    MHD_HTTP_METHOD_GET,
2328                    MHD_HTTP_METHOD_POST,
2329                    MHD_HTTP_METHOD_PUT,
2330                    MHD_HTTP_METHOD_DELETE,
2331                    MHD_HTTP_METHOD_OPTIONS);
2332
2333   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2334               _ ("OpenID Connect REST API initialized\n"));
2335   return api;
2336 }
2337
2338
2339 /**
2340  * Exit point from the plugin.
2341  *
2342  * @param cls the plugin context (as returned by "init")
2343  * @return always NULL
2344  */
2345 void *
2346 libgnunet_plugin_rest_openid_connect_done (void *cls)
2347 {
2348   struct GNUNET_REST_Plugin *api = cls;
2349   struct Plugin *plugin = api->cls;
2350
2351   plugin->cfg = NULL;
2352
2353   struct GNUNET_CONTAINER_MultiHashMapIterator *hashmap_it;
2354   void *value = NULL;
2355   hashmap_it =
2356     GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_cookie_jar_map);
2357   while (GNUNET_YES ==
2358          GNUNET_CONTAINER_multihashmap_iterator_next (hashmap_it, NULL, value))
2359     GNUNET_free_non_null (value);
2360   GNUNET_CONTAINER_multihashmap_iterator_destroy (hashmap_it);
2361   GNUNET_CONTAINER_multihashmap_destroy (OIDC_cookie_jar_map);
2362
2363   hashmap_it =
2364     GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_access_token_map);
2365   while (GNUNET_YES ==
2366          GNUNET_CONTAINER_multihashmap_iterator_next (hashmap_it, NULL, value))
2367     GNUNET_free_non_null (value);
2368   GNUNET_CONTAINER_multihashmap_destroy (OIDC_access_token_map);
2369   GNUNET_CONTAINER_multihashmap_iterator_destroy (hashmap_it);
2370   GNUNET_free_non_null (allow_methods);
2371   GNUNET_free (api);
2372   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2373               "OpenID Connect REST plugin is finished\n");
2374   return NULL;
2375 }
2376
2377
2378 /* end of plugin_rest_openid_connect.c */