RECLAIM/OIDC: Formatting
[oweals/gnunet.git] / src / reclaim / plugin_rest_openid_connect.c
index 1846df9010baa79743267d52ecf338f68931c882..761c9e83d3f5e811b6c0c601eeac865493ca40f8 100644 (file)
@@ -1,6 +1,6 @@
 /*
    This file is part of GNUnet.
-   Copyright (C) 2012-2015 GNUnet e.V.
+   Copyright (C) 2012-2018 GNUnet e.V.
 
    GNUnet is free software: you can redistribute it and/or modify it
    under the terms of the GNU Affero General Public License as published
    WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Affero General Public License for more details.
-  
+
    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+     SPDX-License-Identifier: AGPL3.0-or-later
    */
 /**
  * @author Martin Schanzenbach
  * @brief GNUnet Namestore REST plugin
  *
  */
-
 #include "platform.h"
-#include "gnunet_rest_plugin.h"
-#include "gnunet_identity_service.h"
+#include <inttypes.h>
+#include <jansson.h>
+
 #include "gnunet_gns_service.h"
 #include "gnunet_gnsrecord_lib.h"
+#include "gnunet_identity_service.h"
 #include "gnunet_namestore_service.h"
-#include "gnunet_rest_lib.h"
-#include "gnunet_jsonapi_lib.h"
-#include "gnunet_jsonapi_util.h"
-#include "microhttpd.h"
-#include <jansson.h>
-#include <inttypes.h>
-#include "gnunet_signatures.h"
 #include "gnunet_reclaim_attribute_lib.h"
 #include "gnunet_reclaim_service.h"
+#include "gnunet_rest_lib.h"
+#include "gnunet_rest_plugin.h"
+#include "gnunet_signatures.h"
+#include "microhttpd.h"
 #include "oidc_helper.h"
-
 /**
  * REST root namespace
  */
  */
 #define GNUNET_REST_API_NS_LOGIN "/openid/login"
 
-/**
- * Attribute key
- */
-#define GNUNET_REST_JSONAPI_RECLAIM_ATTRIBUTE "attribute"
-
-/**
- * Ticket key
- */
-#define GNUNET_REST_JSONAPI_IDENTITY_TICKET "ticket"
-
-
-/**
- * Value key
- */
-#define GNUNET_REST_JSONAPI_RECLAIM_ATTRIBUTE_VALUE "value"
-
 /**
  * State while collecting all egos
  */
  */
 #define OIDC_NONCE_KEY "nonce"
 
+/**
+ * OIDC cookie expiration (in seconds)
+ */
+#define OIDC_COOKIE_EXPIRATION 3
+
 /**
  * OIDC cookie header key
  */
  */
 #define OIDC_COOKIE_HEADER_INFORMATION_KEY "Identity="
 
+/**
+ * OIDC cookie header if user cancelled
+ */
+#define OIDC_COOKIE_HEADER_ACCESS_DENIED "Identity=Denied"
+
 /**
  * OIDC expected response_type while authorizing
  */
  */
 #define OIDC_EXPECTED_AUTHORIZATION_SCOPE "openid"
 
+/**
+ * OIDC error key for invalid client
+ */
+#define OIDC_ERROR_KEY_INVALID_CLIENT "invalid_client"
+
+/**
+ * OIDC error key for invalid scopes
+ */
+#define OIDC_ERROR_KEY_INVALID_SCOPE "invalid_scope"
+
+/**
+ * OIDC error key for invalid requests
+ */
+#define OIDC_ERROR_KEY_INVALID_REQUEST "invalid_request"
+
+/**
+ * OIDC error key for invalid tokens
+ */
+#define OIDC_ERROR_KEY_INVALID_TOKEN "invalid_token"
+
+/**
+ * OIDC error key for invalid cookies
+ */
+#define OIDC_ERROR_KEY_INVALID_COOKIE "invalid_cookie"
+
+/**
+ * OIDC error key for generic server errors
+ */
+#define OIDC_ERROR_KEY_SERVER_ERROR "server_error"
+
+/**
+ * OIDC error key for unsupported grants
+ */
+#define OIDC_ERROR_KEY_UNSUPPORTED_GRANT_TYPE "unsupported_grant_type"
+
+/**
+ * OIDC error key for unsupported response types
+ */
+#define OIDC_ERROR_KEY_UNSUPPORTED_RESPONSE_TYPE "unsupported_response_type"
+
+/**
+ * OIDC error key for unauthorized clients
+ */
+#define OIDC_ERROR_KEY_UNAUTHORIZED_CLIENT "unauthorized_client"
+
+/**
+ * OIDC error key for denied access
+ */
+#define OIDC_ERROR_KEY_ACCESS_DENIED "access_denied"
+
+
 /**
  * OIDC ignored parameter array
  */
-static char* OIDC_ignored_parameter_array [] =
-{
-  "display",
-  "prompt",
-  "ui_locales", 
-  "response_mode",
-  "id_token_hint",
-  "login_hint", 
-  "acr_values"
-};
+static char *OIDC_ignored_parameter_array[] = {
+    "display",       "prompt",     "ui_locales", "response_mode",
+    "id_token_hint", "login_hint", "acr_values"};
 
 /**
- * OIDC authorized identities and times hashmap
+ * OIDC Hash map that keeps track of issued cookies
  */
-struct GNUNET_CONTAINER_MultiHashMap *OIDC_identity_login_time;
+struct GNUNET_CONTAINER_MultiHashMap *OIDC_cookie_jar_map;
 
 /**
  * OIDC authorized identities and times hashmap
@@ -186,14 +223,15 @@ struct GNUNET_CONTAINER_MultiHashMap *OIDC_identity_login_time;
 struct GNUNET_CONTAINER_MultiHashMap *OIDC_identity_grants;
 
 /**
- * OIDC ticket/code use only once
+ * OIDC Hash map that keeps track of used authorization code(s)
  */
-struct GNUNET_CONTAINER_MultiHashMap *OIDC_ticket_once;
+struct GNUNET_CONTAINER_MultiHashMap *OIDC_used_ticket_map;
 
 /**
- * OIDC access_token to ticket and ego
+ * Hash map that links the issued access token to the corresponding ticket and
+ * ego
  */
-struct GNUNET_CONTAINER_MultiHashMap *OIDC_interpret_access_token;
+struct GNUNET_CONTAINER_MultiHashMap *OIDC_access_token_map;
 
 /**
  * The configuration handle
@@ -203,7 +241,7 @@ const struct GNUNET_CONFIGURATION_Handle *cfg;
 /**
  * HTTP methods allows for this plugin
  */
-static charallow_methods;
+static char *allow_methods;
 
 /**
  * @brief struct returned by the initialization function of the plugin
@@ -258,11 +296,15 @@ struct OIDC_Variables
    */
   char *login_identity;
 
+  /**
+   * User cancelled authorization/login
+   */
+  int user_cancelled;
+
   /**
    * The response JSON
    */
   json_t *response;
-
 };
 
 /**
@@ -448,12 +490,6 @@ struct RequestHandle
    * Reponse code
    */
   int response_code;
-
-  /**
-   * Response object
-   */
-  struct GNUNET_JSONAPI_Document *resp_object;
-
 };
 
 /**
@@ -467,10 +503,7 @@ cleanup_handle (struct RequestHandle *handle)
   struct GNUNET_RECLAIM_ATTRIBUTE_ClaimListEntry *claim_tmp;
   struct EgoEntry *ego_entry;
   struct EgoEntry *ego_tmp;
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Cleaning up\n");
-  if (NULL != handle->resp_object)
-    GNUNET_JSONAPI_document_delete (handle->resp_object);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Cleaning up\n");
   if (NULL != handle->timeout_task)
     GNUNET_SCHEDULER_cancel (handle->timeout_task);
   if (NULL != handle->identity_handle)
@@ -481,18 +514,12 @@ cleanup_handle (struct RequestHandle *handle)
     GNUNET_RECLAIM_ticket_iteration_stop (handle->ticket_it);
   if (NULL != handle->idp)
     GNUNET_RECLAIM_disconnect (handle->idp);
-  if (NULL != handle->url)
-    GNUNET_free (handle->url);
-  if (NULL != handle->tld)
-    GNUNET_free (handle->tld);
-  if (NULL != handle->redirect_prefix)
-    GNUNET_free (handle->redirect_prefix);
-  if (NULL != handle->redirect_suffix)
-    GNUNET_free (handle->redirect_suffix);
-  if (NULL != handle->emsg)
-    GNUNET_free (handle->emsg);
-  if (NULL != handle->edesc)
-    GNUNET_free (handle->edesc);
+  GNUNET_free_non_null (handle->url);
+  GNUNET_free_non_null (handle->tld);
+  GNUNET_free_non_null (handle->redirect_prefix);
+  GNUNET_free_non_null (handle->redirect_suffix);
+  GNUNET_free_non_null (handle->emsg);
+  GNUNET_free_non_null (handle->edesc);
   if (NULL != handle->gns_op)
     GNUNET_GNS_lookup_cancel (handle->gns_op);
   if (NULL != handle->gns_handle)
@@ -500,51 +527,34 @@ cleanup_handle (struct RequestHandle *handle)
 
   if (NULL != handle->namestore_handle)
     GNUNET_NAMESTORE_disconnect (handle->namestore_handle);
-  if (NULL != handle->oidc)
-  {
-    if (NULL != handle->oidc->client_id)
-      GNUNET_free(handle->oidc->client_id);
-    if (NULL != handle->oidc->login_identity)
-      GNUNET_free(handle->oidc->login_identity);
-    if (NULL != handle->oidc->nonce)
-      GNUNET_free(handle->oidc->nonce);
-    if (NULL != handle->oidc->redirect_uri)
-      GNUNET_free(handle->oidc->redirect_uri);
-    if (NULL != handle->oidc->response_type)
-      GNUNET_free(handle->oidc->response_type);
-    if (NULL != handle->oidc->scope)
-      GNUNET_free(handle->oidc->scope);
-    if (NULL != handle->oidc->state)
-      GNUNET_free(handle->oidc->state);
-    if (NULL != handle->oidc->response)
-      json_decref(handle->oidc->response);
-    GNUNET_free(handle->oidc);
-  }
-  if ( NULL != handle->attr_list )
-  {
-    for (claim_entry = handle->attr_list->list_head;
-         NULL != claim_entry;)
-    {
+  if (NULL != handle->oidc) {
+    GNUNET_free_non_null (handle->oidc->client_id);
+    GNUNET_free_non_null (handle->oidc->login_identity);
+    GNUNET_free_non_null (handle->oidc->nonce);
+    GNUNET_free_non_null (handle->oidc->redirect_uri);
+    GNUNET_free_non_null (handle->oidc->response_type);
+    GNUNET_free_non_null (handle->oidc->scope);
+    GNUNET_free_non_null (handle->oidc->state);
+    json_decref (handle->oidc->response);
+    GNUNET_free (handle->oidc);
+  }
+  if (NULL != handle->attr_list) {
+    for (claim_entry = handle->attr_list->list_head; NULL != claim_entry;) {
       claim_tmp = claim_entry;
       claim_entry = claim_entry->next;
-      GNUNET_free(claim_tmp->claim);
-      GNUNET_free(claim_tmp);
+      GNUNET_free (claim_tmp->claim);
+      GNUNET_free (claim_tmp);
     }
     GNUNET_free (handle->attr_list);
   }
-  for (ego_entry = handle->ego_head;
-       NULL != ego_entry;)
-  {
+  for (ego_entry = handle->ego_head; NULL != ego_entry;) {
     ego_tmp = ego_entry;
     ego_entry = ego_entry->next;
     GNUNET_free (ego_tmp->identifier);
     GNUNET_free (ego_tmp->keystring);
     GNUNET_free (ego_tmp);
   }
-  if (NULL != handle->attr_it)
-  {
-    GNUNET_free(handle->attr_it);
-  }
+  GNUNET_free_non_null (handle->attr_it);
   GNUNET_free (handle);
 }
 
@@ -567,22 +577,20 @@ do_error (void *cls)
   struct MHD_Response *resp;
   char *json_error;
 
-  GNUNET_asprintf (&json_error, "{ \"error\" : \"%s\", \"error_description\" : \"%s\"%s%s%s}",
-                   handle->emsg,
-                   (NULL != handle->edesc) ? handle->edesc : "",
-                   (NULL != handle->oidc->state) ? ", \"state\":\"" : "",
-                   (NULL != handle->oidc->state) ? handle->oidc->state : "",
-                   (NULL != handle->oidc->state) ? "\"" : "");
-  if ( 0 == handle->response_code )
-  {
+  GNUNET_asprintf (
+      &json_error,
+      "{ \"error\" : \"%s\", \"error_description\" : \"%s\"%s%s%s}",
+      handle->emsg, (NULL != handle->edesc) ? handle->edesc : "",
+      (NULL != handle->oidc->state) ? ", \"state\":\"" : "",
+      (NULL != handle->oidc->state) ? handle->oidc->state : "",
+      (NULL != handle->oidc->state) ? "\"" : "");
+  if (0 == handle->response_code)
     handle->response_code = MHD_HTTP_BAD_REQUEST;
-  }
   resp = GNUNET_REST_create_response (json_error);
   if (MHD_HTTP_UNAUTHORIZED == handle->response_code)
-  {
-    MHD_add_response_header(resp, "WWW-Authenticate", "Basic");
-  }
-  MHD_add_response_header (resp, "Content-Type", "application/json");
+    MHD_add_response_header (resp, MHD_HTTP_HEADER_WWW_AUTHENTICATE, "Basic");
+  MHD_add_response_header (resp, MHD_HTTP_HEADER_CONTENT_TYPE,
+                           "application/json");
   handle->proc (handle->proc_cls, resp, handle->response_code);
   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
   GNUNET_free (json_error);
@@ -603,10 +611,9 @@ do_userinfo_error (void *cls)
   char *error;
 
   GNUNET_asprintf (&error, "error=\"%s\", error_description=\"%s\"",
-                   handle->emsg,
-                   (NULL != handle->edesc) ? handle->edesc : "");
+                   handle->emsg, (NULL != handle->edesc) ? handle->edesc : "");
   resp = GNUNET_REST_create_response ("");
-  MHD_add_response_header(resp, "WWW-Authenticate", error);
+  MHD_add_response_header (resp, MHD_HTTP_HEADER_WWW_AUTHENTICATE, "Bearer");
   handle->proc (handle->proc_cls, resp, handle->response_code);
   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
   GNUNET_free (error);
@@ -623,9 +630,8 @@ do_redirect_error (void *cls)
 {
   struct RequestHandle *handle = cls;
   struct MHD_Response *resp;
-  char* redirect;
-  GNUNET_asprintf (&redirect,
-                   "%s?error=%s&error_description=%s%s%s",
+  char *redirect;
+  GNUNET_asprintf (&redirect, "%s?error=%s&error_description=%s%s%s",
                    handle->oidc->redirect_uri, handle->emsg, handle->edesc,
                    (NULL != handle->oidc->state) ? "&state=" : "",
                    (NULL != handle->oidc->state) ? handle->oidc->state : "");
@@ -658,7 +664,7 @@ do_timeout (void *cls)
 static void
 return_userinfo_response (void *cls)
 {
-  charresult_str;
+  char *result_str;
   struct RequestHandle *handle = cls;
   struct MHD_Response *resp;
 
@@ -671,21 +677,35 @@ return_userinfo_response (void *cls)
 }
 
 /**
- * Returns base64 encoded string without padding
+ * Returns base64 encoded string urlencoded
  *
  * @param string the string to encode
  * @return base64 encoded string
  */
-static char*
-base_64_encode(const char *s)
+static char *
+base64_encode (const char *s)
 {
   char *enc;
+  char *enc_urlencode;
   char *tmp;
-
-  GNUNET_STRINGS_base64_encode(s, strlen(s), &enc);
-  tmp = strrchr (enc, '=');
-  *tmp = '\0';
-  return enc;
+  int i;
+  int num_pads = 0;
+
+  GNUNET_STRINGS_base64_encode (s, strlen (s), &enc);
+  tmp = strchr (enc, '=');
+  num_pads = strlen (enc) - (tmp - enc);
+  GNUNET_assert ((3 > num_pads) && (0 <= num_pads));
+  if (0 == num_pads)
+    return enc;
+  enc_urlencode = GNUNET_malloc (strlen (enc) + num_pads * 2);
+  strcpy (enc_urlencode, enc);
+  GNUNET_free (enc);
+  tmp = strchr (enc_urlencode, '=');
+  for (i = 0; i < num_pads; i++) {
+    strcpy (tmp, "%3D"); // replace '=' with '%3D'
+    tmp += 3;
+  }
+  return enc_urlencode;
 }
 
 /**
@@ -696,23 +716,21 @@ base_64_encode(const char *s)
  * @param cls the RequestHandle
  */
 static void
-options_cont (struct GNUNET_REST_RequestHandle *con_handle,
-              const char* url,
+options_cont (struct GNUNET_REST_RequestHandle *con_handle, const char *url,
               void *cls)
 {
   struct MHD_Response *resp;
   struct RequestHandle *handle = cls;
 
-  //For now, independent of path return all options
+  // For now, independent of path return all options
   resp = GNUNET_REST_create_response (NULL);
-  MHD_add_response_header (resp,
-                           "Access-Control-Allow-Methods",
-                           allow_methods);
+  MHD_add_response_header (resp, "Access-Control-Allow-Methods", allow_methods);
   handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
   cleanup_handle (handle);
   return;
 }
 
+
 /**
  * Interprets cookie header and pass its identity keystring to handle
  */
@@ -723,91 +741,108 @@ cookie_identity_interpretation (struct RequestHandle *handle)
   char *cookies;
   struct GNUNET_TIME_Absolute current_time, *relog_time;
   char delimiter[] = "; ";
+  char *tmp_cookies;
+  char *token;
+  char *value;
 
-  //gets identity of login try with cookie
+  // gets identity of login try with cookie
   GNUNET_CRYPTO_hash (OIDC_COOKIE_HEADER_KEY, strlen (OIDC_COOKIE_HEADER_KEY),
                       &cache_key);
-  if ( GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->header_param_map,
-                                                             &cache_key) )
-  {
-    //splits cookies and find 'Identity' cookie
-    cookies = GNUNET_CONTAINER_multihashmap_get ( handle->rest_handle->header_param_map, &cache_key);
-    handle->oidc->login_identity = strtok(cookies, delimiter);
-
-    while ( NULL != handle->oidc->login_identity )
-    {
-      if ( NULL != strstr (handle->oidc->login_identity, OIDC_COOKIE_HEADER_INFORMATION_KEY) )
-      {
-        break;
-      }
-      handle->oidc->login_identity = strtok (NULL, delimiter);
-    }
-    GNUNET_CRYPTO_hash (handle->oidc->login_identity, strlen (handle->oidc->login_identity),
-                        &cache_key);
-    if ( GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (OIDC_identity_login_time, &cache_key) )
-    {
-      relog_time = GNUNET_CONTAINER_multihashmap_get (OIDC_identity_login_time,
-                                                      &cache_key);
-      current_time = GNUNET_TIME_absolute_get ();
-      // 30 min after old login -> redirect to login
-      if ( current_time.abs_value_us <= relog_time->abs_value_us )
-      {
-        handle->oidc->login_identity = strtok(handle->oidc->login_identity, OIDC_COOKIE_HEADER_INFORMATION_KEY);
-        handle->oidc->login_identity = GNUNET_strdup(handle->oidc->login_identity);
-      } else {
-        handle->oidc->login_identity = NULL;
-      }
-    }
-    else
-    {
-      handle->oidc->login_identity = NULL;
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->header_param_map, &cache_key)) {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "No cookie found\n");
+    return;
+  }
+  // splits cookies and find 'Identity' cookie
+  tmp_cookies = GNUNET_CONTAINER_multihashmap_get (
+      handle->rest_handle->header_param_map, &cache_key);
+  cookies = GNUNET_strdup (tmp_cookies);
+  token = strtok (cookies, delimiter);
+  handle->oidc->user_cancelled = GNUNET_NO;
+  handle->oidc->login_identity = NULL;
+  if (NULL == token) {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unable to parse cookie: %s\n",
+                cookies);
+    GNUNET_free (cookies);
+    return;
+  }
+
+  while (NULL != token) {
+    if (0 == strcmp (token, OIDC_COOKIE_HEADER_ACCESS_DENIED)) {
+      handle->oidc->user_cancelled = GNUNET_YES;
+      GNUNET_free (cookies);
+      return;
     }
+    if (NULL != strstr (token, OIDC_COOKIE_HEADER_INFORMATION_KEY))
+      break;
+    token = strtok (NULL, delimiter);
+  }
+  if (NULL == token) {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No cookie value to process: %s\n",
+                cookies);
+    GNUNET_free (cookies);
+    return;
+  }
+  GNUNET_CRYPTO_hash (token, strlen (token), &cache_key);
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (OIDC_cookie_jar_map,
+                                                           &cache_key)) {
+    GNUNET_log (
+        GNUNET_ERROR_TYPE_WARNING,
+        "Found cookie `%s', but no corresponding expiration entry present...\n",
+        token);
+    GNUNET_free (cookies);
+    return;
+  }
+  relog_time =
+      GNUNET_CONTAINER_multihashmap_get (OIDC_cookie_jar_map, &cache_key);
+  current_time = GNUNET_TIME_absolute_get ();
+  // 30 min after old login -> redirect to login
+  if (current_time.abs_value_us > relog_time->abs_value_us) {
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                "Found cookie `%s', but it is expired.\n", token);
+    GNUNET_free (cookies);
+    return;
   }
+  value = strtok (token, OIDC_COOKIE_HEADER_INFORMATION_KEY);
+  GNUNET_assert (NULL != value);
+  handle->oidc->login_identity = GNUNET_strdup (value);
 }
 
 /**
  * Redirects to login page stored in configuration file
  */
 static void
-login_redirection(void *cls)
+login_redirect (void *cls)
 {
   char *login_base_url;
   char *new_redirect;
   struct MHD_Response *resp;
   struct RequestHandle *handle = cls;
 
-  if ( GNUNET_OK
-       == GNUNET_CONFIGURATION_get_value_string (cfg, "reclaim-rest-plugin",
-                                                 "address", &login_base_url) )
-  {
+  if (GNUNET_OK ==
+      GNUNET_CONFIGURATION_get_value_string (cfg, "reclaim-rest-plugin",
+                                             "address", &login_base_url)) {
     GNUNET_asprintf (&new_redirect, "%s?%s=%s&%s=%s&%s=%s&%s=%s&%s=%s&%s=%s",
-                     login_base_url,
-                     OIDC_RESPONSE_TYPE_KEY,
-                     handle->oidc->response_type,
-                     OIDC_CLIENT_ID_KEY,
-                     handle->oidc->client_id,
-                     OIDC_REDIRECT_URI_KEY,
-                     handle->oidc->redirect_uri,
-                     OIDC_SCOPE_KEY,
-                     handle->oidc->scope,
-                     OIDC_STATE_KEY,
+                     login_base_url, OIDC_RESPONSE_TYPE_KEY,
+                     handle->oidc->response_type, OIDC_CLIENT_ID_KEY,
+                     handle->oidc->client_id, OIDC_REDIRECT_URI_KEY,
+                     handle->oidc->redirect_uri, OIDC_SCOPE_KEY,
+                     handle->oidc->scope, OIDC_STATE_KEY,
                      (NULL != handle->oidc->state) ? handle->oidc->state : "",
                      OIDC_NONCE_KEY,
                      (NULL != handle->oidc->nonce) ? handle->oidc->nonce : "");
     resp = GNUNET_REST_create_response ("");
     MHD_add_response_header (resp, "Location", new_redirect);
-    GNUNET_free(login_base_url);
-  }
-  else
-  {
-    handle->emsg = GNUNET_strdup("server_error");
+    GNUNET_free (login_base_url);
+  } else {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
     handle->edesc = GNUNET_strdup ("gnunet configuration failed");
     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
   handle->proc (handle->proc_cls, resp, MHD_HTTP_FOUND);
-  GNUNET_free(new_redirect);
+  GNUNET_free (new_redirect);
   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
 }
 
@@ -818,17 +853,18 @@ static void
 oidc_iteration_error (void *cls)
 {
   struct RequestHandle *handle = cls;
-  handle->emsg = GNUNET_strdup("INTERNAL_SERVER_ERROR");
+  handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
   handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
   GNUNET_SCHEDULER_add_now (&do_error, handle);
 }
 
+
+/**
+ * Issues ticket and redirects to relying party with the authorization code as
+ * parameter. Otherwise redirects with error
+ */
 static void
-get_client_name_result (void *cls,
-                        const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
-                        const char *label,
-                        unsigned int rd_count,
-                        const struct GNUNET_GNSRECORD_Data *rd)
+oidc_ticket_issue_cb (void *cls, const struct GNUNET_RECLAIM_Ticket *ticket)
 {
   struct RequestHandle *handle = cls;
   struct MHD_Response *resp;
@@ -837,19 +873,32 @@ get_client_name_result (void *cls,
   char *code_json_string;
   char *code_base64_final_string;
 
-  ticket_str = GNUNET_STRINGS_data_to_string_alloc (&handle->ticket,
-                                                    sizeof (struct GNUNET_RECLAIM_Ticket));
-  //TODO change if more attributes are needed (see max_age)
-  code_json_string = OIDC_build_authz_code (&handle->priv_key,
-                                            &handle->ticket,
+  handle->idp_op = NULL;
+  handle->ticket = *ticket;
+  if (NULL == ticket) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
+    handle->edesc = GNUNET_strdup ("Server cannot generate ticket.");
+    GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
+    return;
+  }
+  ticket_str = GNUNET_STRINGS_data_to_string_alloc (
+      &handle->ticket, sizeof (struct GNUNET_RECLAIM_Ticket));
+  // TODO change if more attributes are needed (see max_age)
+  code_json_string = OIDC_build_authz_code (&handle->priv_key, &handle->ticket,
                                             handle->oidc->nonce);
-  code_base64_final_string = base_64_encode(code_json_string);
-  GNUNET_asprintf (&redirect_uri, "%s.%s/%s?%s=%s&state=%s",
-                   handle->redirect_prefix,
-                   handle->tld,
-                   handle->redirect_suffix,
-                   handle->oidc->response_type,
-                   code_base64_final_string, handle->oidc->state);
+  code_base64_final_string = base64_encode (code_json_string);
+  if ((NULL != handle->redirect_prefix) && (NULL != handle->redirect_suffix) &&
+      (NULL != handle->tld)) {
+
+    GNUNET_asprintf (&redirect_uri, "%s.%s/%s?%s=%s&state=%s",
+                     handle->redirect_prefix, handle->tld,
+                     handle->redirect_suffix, handle->oidc->response_type,
+                     code_base64_final_string, handle->oidc->state);
+  } else {
+    GNUNET_asprintf (&redirect_uri, "%s?%s=%s&state=%s",
+                     handle->oidc->redirect_uri, handle->oidc->response_type,
+                     code_base64_final_string, handle->oidc->state);
+  }
   resp = GNUNET_REST_create_response ("");
   MHD_add_response_header (resp, "Location", redirect_uri);
   handle->proc (handle->proc_cls, resp, MHD_HTTP_FOUND);
@@ -858,95 +907,6 @@ get_client_name_result (void *cls,
   GNUNET_free (ticket_str);
   GNUNET_free (code_json_string);
   GNUNET_free (code_base64_final_string);
-  return;
-
-}
-
-
-static void
-get_client_name_error (void *cls)
-{
-  struct RequestHandle *handle = cls;
-
-  handle->emsg = GNUNET_strdup("server_error");
-  handle->edesc = GNUNET_strdup("Server cannot generate ticket, no name found for client.");
-  GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
-}
-
-
-static void
-lookup_redirect_uri_result (void *cls,
-                            uint32_t rd_count,
-                            const struct GNUNET_GNSRECORD_Data *rd)
-{
-  struct RequestHandle *handle = cls;
-  char *tmp;
-  char *tmp_key_str;
-  char *pos;
-  struct GNUNET_CRYPTO_EcdsaPublicKey redirect_zone;
-
-  handle->gns_op = NULL;
-  if (1 != rd_count)
-  {
-    handle->emsg = GNUNET_strdup("server_error");
-    handle->edesc = GNUNET_strdup("Server cannot generate ticket, redirect uri not found.");
-    GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
-    return;
-  }
-  tmp = GNUNET_strdup (rd->data);
-  pos = strrchr (tmp,
-                 (unsigned char) '.');
-  *pos = '\0';
-  handle->redirect_prefix = GNUNET_strdup (tmp);
-  tmp_key_str = pos + 1;
-  pos = strchr (tmp_key_str,
-                (unsigned char) '/');
-  *pos = '\0';
-  handle->redirect_suffix = GNUNET_strdup (pos + 1);
-  
-  GNUNET_STRINGS_string_to_data (tmp_key_str,
-                                 strlen (tmp_key_str),
-                                 &redirect_zone,
-                                 sizeof (redirect_zone));
-
-  GNUNET_NAMESTORE_zone_to_name (handle->namestore_handle,
-                                 &handle->priv_key,
-                                 &redirect_zone,
-                                 &get_client_name_error,
-                                 handle,
-                                 &get_client_name_result,
-                                 handle);
-  GNUNET_free (tmp);
-
-}
-
-/**
- * Issues ticket and redirects to relying party with the authorization code as
- * parameter. Otherwise redirects with error
- */
-static void
-oidc_ticket_issue_cb (void* cls,
-                      const struct GNUNET_RECLAIM_Ticket *ticket)
-{
-  struct RequestHandle *handle = cls;
-
-  handle->idp_op = NULL;
-  handle->ticket = *ticket;
-  if (NULL == ticket)
-  {
-    handle->emsg = GNUNET_strdup("server_error");
-    handle->edesc = GNUNET_strdup("Server cannot generate ticket.");
-    GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
-    return;
-  }
-  handle->gns_op = GNUNET_GNS_lookup (handle->gns_handle,
-                                      handle->oidc->redirect_uri,
-                                      &handle->oidc->client_pkey,
-                                      GNUNET_DNSPARSER_TYPE_TXT,
-                                      GNUNET_GNS_LO_DEFAULT,
-                                      &lookup_redirect_uri_result,
-                                      handle);
-
 }
 
 static void
@@ -955,19 +915,15 @@ oidc_collect_finished_cb (void *cls)
   struct RequestHandle *handle = cls;
   handle->attr_it = NULL;
   handle->ticket_it = NULL;
-  if (NULL == handle->attr_list->list_head)
-  {
-    handle->emsg = GNUNET_strdup("invalid_scope");
-    handle->edesc = GNUNET_strdup("The requested scope is not available.");
+  if (NULL == handle->attr_list->list_head) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_SCOPE);
+    handle->edesc = GNUNET_strdup ("The requested scope is not available.");
     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
     return;
   }
-  handle->idp_op = GNUNET_RECLAIM_ticket_issue (handle->idp,
-                                                &handle->priv_key,
-                                                &handle->oidc->client_pkey,
-                                                handle->attr_list,
-                                                &oidc_ticket_issue_cb,
-                                                handle);
+  handle->idp_op = GNUNET_RECLAIM_ticket_issue (
+      handle->idp, &handle->priv_key, &handle->oidc->client_pkey,
+      handle->attr_list, &oidc_ticket_issue_cb, handle);
 }
 
 
@@ -981,39 +937,35 @@ oidc_attr_collect (void *cls,
 {
   struct RequestHandle *handle = cls;
   struct GNUNET_RECLAIM_ATTRIBUTE_ClaimListEntry *le;
-  charscope_variables;
-  charscope_variable;
-  char delimiter[]=" ";
+  char *scope_variables;
+  char *scope_variable;
+  char delimiter[] = " ";
 
-  if ( (NULL == attr->name) || (NULL == attr->data) )
-  {
+  if ((NULL == attr->name) || (NULL == attr->data)) {
     GNUNET_RECLAIM_get_attributes_next (handle->attr_it);
     return;
   }
 
-  scope_variables = GNUNET_strdup(handle->oidc->scope);
+  scope_variables = GNUNET_strdup (handle->oidc->scope);
   scope_variable = strtok (scope_variables, delimiter);
-  while (NULL != scope_variable)
-  {
-    if ( 0 == strcmp (attr->name, scope_variable) )
-    {
+  while (NULL != scope_variable) {
+    if (0 == strcmp (attr->name, scope_variable)) {
       break;
     }
     scope_variable = strtok (NULL, delimiter);
   }
-  if ( NULL == scope_variable )
-  {
+  if (NULL == scope_variable) {
     GNUNET_RECLAIM_get_attributes_next (handle->attr_it);
-    GNUNET_free(scope_variables);
+    GNUNET_free (scope_variables);
     return;
   }
-  GNUNET_free(scope_variables);
+  GNUNET_free (scope_variables);
 
-  le = GNUNET_new(struct GNUNET_RECLAIM_ATTRIBUTE_ClaimListEntry);
+  le = GNUNET_new (struct GNUNET_RECLAIM_ATTRIBUTE_ClaimListEntry);
   le->claim = GNUNET_RECLAIM_ATTRIBUTE_claim_new (attr->name, attr->type,
                                                   attr->data, attr->data_size);
-  GNUNET_CONTAINER_DLL_insert(handle->attr_list->list_head,
-                              handle->attr_list->list_tail, le);
+  GNUNET_CONTAINER_DLL_insert (handle->attr_list->list_head,
+                               handle->attr_list->list_tail, le);
   GNUNET_RECLAIM_get_attributes_next (handle->attr_it);
 }
 
@@ -1022,7 +974,7 @@ oidc_attr_collect (void *cls,
  * Checks time and cookie and redirects accordingly
  */
 static void
-login_check (void *cls)
+code_redirect (void *cls)
 {
   struct RequestHandle *handle = cls;
   struct GNUNET_TIME_Absolute current_time, *relog_time;
@@ -1030,62 +982,150 @@ login_check (void *cls)
   struct GNUNET_HashCode cache_key;
   char *identity_cookie;
 
-  GNUNET_asprintf (&identity_cookie, "Identity=%s", handle->oidc->login_identity);
+  GNUNET_asprintf (&identity_cookie, "Identity=%s",
+                   handle->oidc->login_identity);
   GNUNET_CRYPTO_hash (identity_cookie, strlen (identity_cookie), &cache_key);
-  GNUNET_free(identity_cookie);
-  //No login time for identity -> redirect to login
-  if ( GNUNET_YES
-       == GNUNET_CONTAINER_multihashmap_contains (OIDC_identity_login_time,
-                                                  &cache_key) )
-  {
-    relog_time = GNUNET_CONTAINER_multihashmap_get (OIDC_identity_login_time,
-                                                    &cache_key);
+  GNUNET_free (identity_cookie);
+  // No login time for identity -> redirect to login
+  if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (OIDC_cookie_jar_map,
+                                                            &cache_key)) {
+    relog_time =
+        GNUNET_CONTAINER_multihashmap_get (OIDC_cookie_jar_map, &cache_key);
     current_time = GNUNET_TIME_absolute_get ();
     // 30 min after old login -> redirect to login
-    if ( current_time.abs_value_us <= relog_time->abs_value_us )
-    {
-      if ( GNUNET_OK
-           != GNUNET_CRYPTO_ecdsa_public_key_from_string (
-                                                          handle->oidc->login_identity,
-                                                          strlen (handle->oidc->login_identity), &pubkey) )
-      {
-        handle->emsg = GNUNET_strdup("invalid_cookie");
-        handle->edesc = GNUNET_strdup(
-                                      "The cookie of a login identity is not valid");
+    if (current_time.abs_value_us <= relog_time->abs_value_us) {
+      if (GNUNET_OK != GNUNET_CRYPTO_ecdsa_public_key_from_string (
+                           handle->oidc->login_identity,
+                           strlen (handle->oidc->login_identity), &pubkey)) {
+        handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_COOKIE);
+        handle->edesc =
+            GNUNET_strdup ("The cookie of a login identity is not valid");
         GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
         return;
       }
       // iterate over egos and compare their public key
-      for (handle->ego_entry = handle->ego_head;
-           NULL != handle->ego_entry; handle->ego_entry = handle->ego_entry->next)
-      {
+      for (handle->ego_entry = handle->ego_head; NULL != handle->ego_entry;
+           handle->ego_entry = handle->ego_entry->next) {
         GNUNET_IDENTITY_ego_get_public_key (handle->ego_entry->ego, &ego_pkey);
-        if ( 0
-             == memcmp (&ego_pkey, &pubkey,
-                        sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey)) )
-        {
-          handle->priv_key = *GNUNET_IDENTITY_ego_get_private_key (
-                                                                   handle->ego_entry->ego);
-          handle->resp_object = GNUNET_JSONAPI_document_new ();
+        if (0 == memcmp (&ego_pkey, &pubkey,
+                         sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey))) {
+          handle->priv_key =
+              *GNUNET_IDENTITY_ego_get_private_key (handle->ego_entry->ego);
           handle->idp = GNUNET_RECLAIM_connect (cfg);
-          handle->attr_list = GNUNET_new(
-                                         struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList);
+          handle->attr_list =
+              GNUNET_new (struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList);
           handle->attr_it = GNUNET_RECLAIM_get_attributes_start (
-                                                                 handle->idp, &handle->priv_key, &oidc_iteration_error, handle,
-                                                                 &oidc_attr_collect, handle, &oidc_collect_finished_cb, handle);
+              handle->idp, &handle->priv_key, &oidc_iteration_error, handle,
+              &oidc_attr_collect, handle, &oidc_collect_finished_cb, handle);
           return;
         }
       }
-      //handle->emsg = GNUNET_strdup("invalid_cookie");
-      //handle->edesc = GNUNET_strdup(
-      //                              "The cookie of the login identity is not valid");
-      //GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
-      GNUNET_SCHEDULER_add_now (&login_redirection,handle);
+      GNUNET_SCHEDULER_add_now (&login_redirect, handle);
       return;
     }
   }
 }
 
+
+static void
+build_redirect (void *cls)
+{
+  struct RequestHandle *handle = cls;
+  struct MHD_Response *resp;
+  char *redirect_uri;
+
+  if (GNUNET_YES == handle->oidc->user_cancelled) {
+    if ((NULL != handle->redirect_prefix) &&
+        (NULL != handle->redirect_suffix) && (NULL != handle->tld)) {
+      GNUNET_asprintf (
+          &redirect_uri, "%s.%s/%s?error=%s&error_description=%s&state=%s",
+          handle->redirect_prefix, handle->tld, handle->redirect_suffix,
+          "access_denied", "User denied access", handle->oidc->state);
+    } else {
+      GNUNET_asprintf (&redirect_uri,
+                       "%s?error=%s&error_description=%s&state=%s",
+                       handle->oidc->redirect_uri, "access_denied",
+                       "User denied access", handle->oidc->state);
+    }
+    resp = GNUNET_REST_create_response ("");
+    MHD_add_response_header (resp, "Location", redirect_uri);
+    handle->proc (handle->proc_cls, resp, MHD_HTTP_FOUND);
+    GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
+    GNUNET_free (redirect_uri);
+    return;
+  }
+  GNUNET_SCHEDULER_add_now (&code_redirect, handle);
+}
+
+
+static void
+lookup_redirect_uri_result (void *cls, uint32_t rd_count,
+                            const struct GNUNET_GNSRECORD_Data *rd)
+{
+  struct RequestHandle *handle = cls;
+  char *tmp;
+  char *tmp_key_str;
+  char *pos;
+  struct GNUNET_CRYPTO_EcdsaPublicKey redirect_zone;
+
+  handle->gns_op = NULL;
+  if (0 == rd_count) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
+    handle->edesc = GNUNET_strdup (
+        "Server cannot generate ticket, redirect uri not found.");
+    GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
+    return;
+  }
+  for (int i = 0; i < rd_count; i++) {
+    if (GNUNET_GNSRECORD_TYPE_RECLAIM_OIDC_REDIRECT != rd[i].record_type)
+      continue;
+    if (0 != strncmp (rd[i].data, handle->oidc->redirect_uri, rd[i].data_size))
+      continue;
+    tmp = GNUNET_strndup (rd[i].data, rd[i].data_size);
+    if (NULL == strstr (tmp, handle->oidc->client_id)) {
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                  "Redirect uri %s does not contain client_id %s", tmp,
+                  handle->oidc->client_id);
+    } else {
+
+      pos = strrchr (tmp, (unsigned char)'.');
+      *pos = '\0';
+      handle->redirect_prefix = GNUNET_strdup (tmp);
+      tmp_key_str = pos + 1;
+      pos = strchr (tmp_key_str, (unsigned char)'/');
+      *pos = '\0';
+      handle->redirect_suffix = GNUNET_strdup (pos + 1);
+
+      GNUNET_STRINGS_string_to_data (tmp_key_str, strlen (tmp_key_str),
+                                     &redirect_zone, sizeof (redirect_zone));
+    }
+    GNUNET_SCHEDULER_add_now (&build_redirect, handle);
+    GNUNET_free (tmp);
+    return;
+  }
+  handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
+  handle->edesc =
+      GNUNET_strdup ("Server cannot generate ticket, redirect uri not found.");
+  GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
+}
+
+
+/**
+ * Initiate redirect back to client.
+ */
+static void
+client_redirect (void *cls)
+{
+  struct RequestHandle *handle = cls;
+
+  /* Lookup client redirect uri to verify request */
+  handle->gns_op = GNUNET_GNS_lookup (
+      handle->gns_handle, GNUNET_GNS_EMPTY_LABEL_AT, &handle->oidc->client_pkey,
+      GNUNET_GNSRECORD_TYPE_RECLAIM_OIDC_REDIRECT, GNUNET_GNS_LO_DEFAULT,
+      &lookup_redirect_uri_result, handle);
+}
+
+
 /**
  * Iteration over all results finished, build final
  * response.
@@ -1099,74 +1139,70 @@ build_authz_response (void *cls)
   struct GNUNET_HashCode cache_key;
 
   char *expected_scope;
-  char delimiter[]=" ";
+  char delimiter[] = " ";
   int number_of_ignored_parameter, iterator;
 
 
   // REQUIRED value: redirect_uri
   GNUNET_CRYPTO_hash (OIDC_REDIRECT_URI_KEY, strlen (OIDC_REDIRECT_URI_KEY),
                       &cache_key);
-  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                                           &cache_key))
-  {
-    handle->emsg=GNUNET_strdup("invalid_request");
-    handle->edesc=GNUNET_strdup("missing parameter redirect_uri");
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->url_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("missing parameter redirect_uri");
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
-  handle->oidc->redirect_uri = GNUNET_strdup (GNUNET_CONTAINER_multihashmap_get(handle->rest_handle->url_param_map,
-                                                                                &cache_key));
+  handle->oidc->redirect_uri =
+      GNUNET_strdup (GNUNET_CONTAINER_multihashmap_get (
+          handle->rest_handle->url_param_map, &cache_key));
 
   // REQUIRED value: response_type
   GNUNET_CRYPTO_hash (OIDC_RESPONSE_TYPE_KEY, strlen (OIDC_RESPONSE_TYPE_KEY),
                       &cache_key);
-  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                                           &cache_key))
-  {
-    handle->emsg=GNUNET_strdup("invalid_request");
-    handle->edesc=GNUNET_strdup("missing parameter response_type");
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->url_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("missing parameter response_type");
     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
     return;
   }
-  handle->oidc->response_type = GNUNET_CONTAINER_multihashmap_get(handle->rest_handle->url_param_map,
-                                                                  &cache_key);
+  handle->oidc->response_type = GNUNET_CONTAINER_multihashmap_get (
+      handle->rest_handle->url_param_map, &cache_key);
   handle->oidc->response_type = GNUNET_strdup (handle->oidc->response_type);
 
   // REQUIRED value: scope
   GNUNET_CRYPTO_hash (OIDC_SCOPE_KEY, strlen (OIDC_SCOPE_KEY), &cache_key);
-  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                                           &cache_key))
-  {
-    handle->emsg=GNUNET_strdup("invalid_request");
-    handle->edesc=GNUNET_strdup("missing parameter scope");
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->url_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_SCOPE);
+    handle->edesc = GNUNET_strdup ("missing parameter scope");
     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
     return;
   }
-  handle->oidc->scope = GNUNET_CONTAINER_multihashmap_get(handle->rest_handle->url_param_map,
-                                                          &cache_key);
-  handle->oidc->scope = GNUNET_strdup(handle->oidc->scope);
+  handle->oidc->scope = GNUNET_CONTAINER_multihashmap_get (
+      handle->rest_handle->url_param_map, &cache_key);
+  handle->oidc->scope = GNUNET_strdup (handle->oidc->scope);
 
-  //OPTIONAL value: nonce
+  // OPTIONAL value: nonce
   GNUNET_CRYPTO_hash (OIDC_NONCE_KEY, strlen (OIDC_NONCE_KEY), &cache_key);
-  if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                                            &cache_key))
-  {
-    handle->oidc->nonce = GNUNET_CONTAINER_multihashmap_get(handle->rest_handle->url_param_map,
-                                                            &cache_key);
+  if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (
+                        handle->rest_handle->url_param_map, &cache_key)) {
+    handle->oidc->nonce = GNUNET_CONTAINER_multihashmap_get (
+        handle->rest_handle->url_param_map, &cache_key);
     handle->oidc->nonce = GNUNET_strdup (handle->oidc->nonce);
   }
 
-  //TODO check other values if needed
-  number_of_ignored_parameter = sizeof(OIDC_ignored_parameter_array) / sizeof(char *);
-  for( iterator = 0; iterator < number_of_ignored_parameter; iterator++ )
-  {
+  // TODO check other values if needed
+  number_of_ignored_parameter =
+      sizeof (OIDC_ignored_parameter_array) / sizeof (char *);
+  for (iterator = 0; iterator < number_of_ignored_parameter; iterator++) {
     GNUNET_CRYPTO_hash (OIDC_ignored_parameter_array[iterator],
-                        strlen(OIDC_ignored_parameter_array[iterator]),
+                        strlen (OIDC_ignored_parameter_array[iterator]),
                         &cache_key);
-    if(GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(handle->rest_handle->url_param_map,
-                                                            &cache_key))
-    {
-      handle->emsg=GNUNET_strdup("access_denied");
+    if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (
+                          handle->rest_handle->url_param_map, &cache_key)) {
+      handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_ACCESS_DENIED);
       GNUNET_asprintf (&handle->edesc, "Server will not handle parameter: %s",
                        OIDC_ignored_parameter_array[iterator]);
       GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
@@ -1175,46 +1211,59 @@ build_authz_response (void *cls)
   }
 
   // Checks if response_type is 'code'
-  if( 0 != strcmp( handle->oidc->response_type, OIDC_EXPECTED_AUTHORIZATION_RESPONSE_TYPE ) )
-  {
-    handle->emsg=GNUNET_strdup("unsupported_response_type");
-    handle->edesc=GNUNET_strdup("The authorization server does not support "
-                                "obtaining this authorization code.");
+  if (0 != strcmp (handle->oidc->response_type,
+                   OIDC_EXPECTED_AUTHORIZATION_RESPONSE_TYPE)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_UNSUPPORTED_RESPONSE_TYPE);
+    handle->edesc = GNUNET_strdup ("The authorization server does not support "
+                                   "obtaining this authorization code.");
     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
     return;
   }
 
   // Checks if scope contains 'openid'
-  expected_scope = GNUNET_strdup(handle->oidc->scope);
-  chartest;
+  expected_scope = GNUNET_strdup (handle->oidc->scope);
+  char *test;
   test = strtok (expected_scope, delimiter);
-  while (NULL != test)
-  {
-    if ( 0 == strcmp (OIDC_EXPECTED_AUTHORIZATION_SCOPE, expected_scope) )
-    {
+  while (NULL != test) {
+    if (0 == strcmp (OIDC_EXPECTED_AUTHORIZATION_SCOPE, expected_scope))
       break;
-    }
     test = strtok (NULL, delimiter);
   }
-  if (NULL == test)
-  {
-    handle->emsg = GNUNET_strdup("invalid_scope");
-    handle->edesc=GNUNET_strdup("The requested scope is invalid, unknown, or "
-                                "malformed.");
+  if (NULL == test) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_SCOPE);
+    handle->edesc =
+        GNUNET_strdup ("The requested scope is invalid, unknown, or "
+                       "malformed.");
     GNUNET_SCHEDULER_add_now (&do_redirect_error, handle);
-    GNUNET_free(expected_scope);
+    GNUNET_free (expected_scope);
     return;
   }
 
-  GNUNET_free(expected_scope);
+  GNUNET_free (expected_scope);
+  if ((NULL == handle->oidc->login_identity) &&
+      (GNUNET_NO == handle->oidc->user_cancelled))
+    GNUNET_SCHEDULER_add_now (&login_redirect, handle);
+  else
+    GNUNET_SCHEDULER_add_now (&client_redirect, handle);
+}
+
+/**
+ * Iterate over tlds in config
+ */
+static void
+tld_iter (void *cls, const char *section, const char *option, const char *value)
+{
+  struct RequestHandle *handle = cls;
+  struct GNUNET_CRYPTO_EcdsaPublicKey pkey;
 
-  if( NULL != handle->oidc->login_identity )
-  {
-    GNUNET_SCHEDULER_add_now(&login_check,handle);
+  if (GNUNET_OK != GNUNET_CRYPTO_ecdsa_public_key_from_string (
+                       value, strlen (value), &pkey)) {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Skipping non key %s\n", value);
     return;
   }
-
-  GNUNET_SCHEDULER_add_now(&login_redirection,handle);
+  if (0 == memcmp (&pkey, &handle->oidc->client_pkey,
+                   sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey)))
+    handle->tld = GNUNET_strdup (option + 1);
 }
 
 /**
@@ -1226,8 +1275,7 @@ build_authz_response (void *cls)
  */
 static void
 authorize_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
-                    const char* url,
-                    void *cls)
+                    const char *url, void *cls)
 {
   struct RequestHandle *handle = cls;
   struct GNUNET_HashCode cache_key;
@@ -1235,50 +1283,46 @@ authorize_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
   const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv_key;
   struct GNUNET_CRYPTO_EcdsaPublicKey pkey;
 
-  cookie_identity_interpretation(handle);
+  cookie_identity_interpretation (handle);
 
-  //RECOMMENDED value: state - REQUIRED for answers
+  // RECOMMENDED value: state - REQUIRED for answers
   GNUNET_CRYPTO_hash (OIDC_STATE_KEY, strlen (OIDC_STATE_KEY), &cache_key);
-  if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                                            &cache_key))
-  {
-    handle->oidc->state = GNUNET_CONTAINER_multihashmap_get(handle->rest_handle->url_param_map,
-                                                            &cache_key);
+  if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (
+                        handle->rest_handle->url_param_map, &cache_key)) {
+    handle->oidc->state = GNUNET_CONTAINER_multihashmap_get (
+        handle->rest_handle->url_param_map, &cache_key);
     handle->oidc->state = GNUNET_strdup (handle->oidc->state);
   }
 
   // REQUIRED value: client_id
   GNUNET_CRYPTO_hash (OIDC_CLIENT_ID_KEY, strlen (OIDC_CLIENT_ID_KEY),
                       &cache_key);
-  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                                           &cache_key))
-  {
-    handle->emsg=GNUNET_strdup("invalid_request");
-    handle->edesc=GNUNET_strdup("missing parameter client_id");
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->url_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("missing parameter client_id");
     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
-  handle->oidc->client_id = GNUNET_strdup (GNUNET_CONTAINER_multihashmap_get(handle->rest_handle->url_param_map,
-                                                                             &cache_key));
-
-  if ( GNUNET_OK
-       != GNUNET_CRYPTO_ecdsa_public_key_from_string (handle->oidc->client_id,
-                                                      strlen (handle->oidc->client_id),
-                                                      &handle->oidc->client_pkey) )
-  {
-    handle->emsg = GNUNET_strdup("unauthorized_client");
-    handle->edesc = GNUNET_strdup("The client is not authorized to request an "
-                                  "authorization code using this method.");
+  handle->oidc->client_id = GNUNET_strdup (GNUNET_CONTAINER_multihashmap_get (
+      handle->rest_handle->url_param_map, &cache_key));
+
+  if (GNUNET_OK != GNUNET_CRYPTO_ecdsa_public_key_from_string (
+                       handle->oidc->client_id,
+                       strlen (handle->oidc->client_id),
+                       &handle->oidc->client_pkey)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_UNAUTHORIZED_CLIENT);
+    handle->edesc = GNUNET_strdup ("The client is not authorized to request an "
+                                   "authorization code using this method.");
     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
 
 
-  if ( NULL == handle->ego_head )
-  {
-    handle->emsg = GNUNET_strdup("server_error");
+  if (NULL == handle->ego_head) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
     handle->edesc = GNUNET_strdup ("Egos are missing");
     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
@@ -1286,21 +1330,23 @@ authorize_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
   }
 
   handle->ego_entry = handle->ego_head;
-  handle->priv_key = *GNUNET_IDENTITY_ego_get_private_key (handle->ego_head->ego);
-  //If we know this identity, translated the corresponding TLD
-  //TODO: We might want to have a reverse lookup functionality for TLDs?
-  for (tmp_ego = handle->ego_head; NULL != tmp_ego; tmp_ego = tmp_ego->next)
-  {
+  handle->priv_key =
+      *GNUNET_IDENTITY_ego_get_private_key (handle->ego_head->ego);
+  // If we know this identity, translated the corresponding TLD
+  // TODO: We might want to have a reverse lookup functionality for TLDs?
+  for (tmp_ego = handle->ego_head; NULL != tmp_ego; tmp_ego = tmp_ego->next) {
     priv_key = GNUNET_IDENTITY_ego_get_private_key (tmp_ego->ego);
-    GNUNET_CRYPTO_ecdsa_key_get_public (priv_key,
-                                        &pkey);
-    if ( 0 == memcmp (&pkey, &handle->oidc->client_pkey,
-                      sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey)) )
-    {
+    GNUNET_CRYPTO_ecdsa_key_get_public (priv_key, &pkey);
+    if (0 == memcmp (&pkey, &handle->oidc->client_pkey,
+                     sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey))) {
       handle->tld = GNUNET_strdup (tmp_ego->identifier);
       handle->ego_entry = handle->ego_tail;
     }
-  } 
+  }
+  if (NULL == handle->tld)
+    GNUNET_CONFIGURATION_iterate_section_values (cfg, "gns", tld_iter, handle);
+  if (NULL == handle->tld)
+    handle->tld = GNUNET_strdup (handle->oidc->client_id);
   GNUNET_SCHEDULER_add_now (&build_authz_response, handle);
 }
 
@@ -1312,8 +1358,7 @@ authorize_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
  * @param cls the RequestHandle
  */
 static void
-login_cont (struct GNUNET_REST_RequestHandle *con_handle,
-            const char* url,
+login_cont (struct GNUNET_REST_RequestHandle *con_handle, const char *url,
             void *cls)
 {
   struct MHD_Response *resp = GNUNET_REST_create_response ("");
@@ -1321,48 +1366,52 @@ login_cont (struct GNUNET_REST_RequestHandle *con_handle,
   struct GNUNET_HashCode cache_key;
   struct GNUNET_TIME_Absolute *current_time;
   struct GNUNET_TIME_Absolute *last_time;
-  char* cookie;
+  char *cookie;
+  char *header_val;
   json_t *root;
   json_error_t error;
   json_t *identity;
-  char term_data[handle->rest_handle->data_size+1];
+  char term_data[handle->rest_handle->data_size + 1];
   term_data[handle->rest_handle->data_size] = '\0';
-  GNUNET_memcpy (term_data, handle->rest_handle->data, handle->rest_handle->data_size);
+  GNUNET_memcpy (term_data, handle->rest_handle->data,
+                 handle->rest_handle->data_size);
   root = json_loads (term_data, JSON_DECODE_ANY, &error);
   identity = json_object_get (root, "identity");
-  if ( json_is_string(identity) )
-  {
-    GNUNET_asprintf (&cookie, "Identity=%s", json_string_value (identity));
-    MHD_add_response_header (resp, "Set-Cookie", cookie);
-    MHD_add_response_header (resp, "Access-Control-Allow-Methods", "POST");
-    GNUNET_CRYPTO_hash (cookie, strlen (cookie), &cache_key);
-
-    current_time = GNUNET_new(struct GNUNET_TIME_Absolute);
-    *current_time = GNUNET_TIME_relative_to_absolute (
-                                                      GNUNET_TIME_relative_multiply (GNUNET_TIME_relative_get_second_ (),
-                                                                                     5));
-    last_time = GNUNET_CONTAINER_multihashmap_get(OIDC_identity_login_time, &cache_key);
-    if (NULL != last_time)
-    {
-      GNUNET_free(last_time);
-    }
-    GNUNET_CONTAINER_multihashmap_put (
-                                       OIDC_identity_login_time, &cache_key, current_time,
-                                       GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE);
-
-    handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
-    GNUNET_free(cookie);
-  }
-  else
-  {
+  if (!json_is_string (identity)) {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Error parsing json string from %s\n",
+                term_data);
     handle->proc (handle->proc_cls, resp, MHD_HTTP_BAD_REQUEST);
+    json_decref (root);
+    GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
+    return;
   }
+  GNUNET_asprintf (&cookie, "Identity=%s", json_string_value (identity));
+  GNUNET_asprintf (&header_val, "%s;Max-Age=%d", cookie,
+                   OIDC_COOKIE_EXPIRATION);
+  MHD_add_response_header (resp, "Set-Cookie", header_val);
+  MHD_add_response_header (resp, "Access-Control-Allow-Methods", "POST");
+  GNUNET_CRYPTO_hash (cookie, strlen (cookie), &cache_key);
+
+  if (0 != strcmp (json_string_value (identity), "Denied")) {
+    current_time = GNUNET_new (struct GNUNET_TIME_Absolute);
+    *current_time =
+        GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply (
+            GNUNET_TIME_relative_get_second_ (), OIDC_COOKIE_EXPIRATION));
+    last_time =
+        GNUNET_CONTAINER_multihashmap_get (OIDC_cookie_jar_map, &cache_key);
+    GNUNET_free_non_null (last_time);
+    GNUNET_CONTAINER_multihashmap_put (
+        OIDC_cookie_jar_map, &cache_key, current_time,
+        GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE);
+  }
+  handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
+  GNUNET_free (cookie);
+  GNUNET_free (header_val);
   json_decref (root);
   GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
-  return;
 }
 
-static int 
+static int
 check_authorization (struct RequestHandle *handle,
                      struct GNUNET_CRYPTO_EcdsaPublicKey *cid)
 {
@@ -1376,105 +1425,87 @@ check_authorization (struct RequestHandle *handle,
   int client_exists = GNUNET_NO;
 
   GNUNET_CRYPTO_hash (OIDC_AUTHORIZATION_HEADER_KEY,
-                      strlen (OIDC_AUTHORIZATION_HEADER_KEY),
-                      &cache_key);
-  if ( GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->header_param_map,
-                                                            &cache_key) )
-  {
-    handle->emsg=GNUNET_strdup("invalid_client");
-    handle->edesc=GNUNET_strdup("missing authorization");
+                      strlen (OIDC_AUTHORIZATION_HEADER_KEY), &cache_key);
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->header_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
+    handle->edesc = GNUNET_strdup ("missing authorization");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     return GNUNET_SYSERR;
   }
-  authorization = GNUNET_CONTAINER_multihashmap_get (handle->rest_handle->header_param_map,
-                                                     &cache_key);
+  authorization = GNUNET_CONTAINER_multihashmap_get (
+      handle->rest_handle->header_param_map, &cache_key);
 
-  //split header in "Basic" and [content]
+  // split header in "Basic" and [content]
   credentials = strtok (authorization, " ");
-  if (0 != strcmp ("Basic", credentials))
-  {
-    handle->emsg=GNUNET_strdup("invalid_client");
+  if (0 != strcmp ("Basic", credentials)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     return GNUNET_SYSERR;
   }
-  credentials = strtok(NULL, " ");
-  if (NULL == credentials)
-  {
-    handle->emsg=GNUNET_strdup("invalid_client");
+  credentials = strtok (NULL, " ");
+  if (NULL == credentials) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     return GNUNET_SYSERR;
   }
-  GNUNET_STRINGS_base64_decode (credentials,
-                                strlen (credentials),
-                                (void**)&basic_authorization);
+  GNUNET_STRINGS_base64_decode (credentials, strlen (credentials),
+                                (void **)&basic_authorization);
 
-  if ( NULL == basic_authorization )
-  {
-    handle->emsg=GNUNET_strdup("invalid_client");
+  if (NULL == basic_authorization) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     return GNUNET_SYSERR;
   }
   client_id = strtok (basic_authorization, ":");
-  if ( NULL == client_id )
-  {
-    GNUNET_free_non_null(basic_authorization);
-    handle->emsg=GNUNET_strdup("invalid_client");
+  if (NULL == client_id) {
+    GNUNET_free_non_null (basic_authorization);
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     return GNUNET_SYSERR;
   }
   pass = strtok (NULL, ":");
-  if (NULL == pass)
-  {
-    GNUNET_free_non_null(basic_authorization);
-    handle->emsg=GNUNET_strdup("invalid_client");
+  if (NULL == pass) {
+    GNUNET_free_non_null (basic_authorization);
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     return GNUNET_SYSERR;
   }
 
-  //check client password
-  if ( GNUNET_OK
-       == GNUNET_CONFIGURATION_get_value_string (cfg, "reclaim-rest-plugin",
-                                                 "psw", &expected_pass) )
-  {
-    if (0 != strcmp (expected_pass, pass))
-    {
-      GNUNET_free_non_null(basic_authorization);
-      GNUNET_free(expected_pass);
-      handle->emsg=GNUNET_strdup("invalid_client");
+  // check client password
+  if (GNUNET_OK == GNUNET_CONFIGURATION_get_value_string (
+                       cfg, "reclaim-rest-plugin", "psw", &expected_pass)) {
+    if (0 != strcmp (expected_pass, pass)) {
+      GNUNET_free_non_null (basic_authorization);
+      GNUNET_free (expected_pass);
+      handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
       handle->response_code = MHD_HTTP_UNAUTHORIZED;
       return GNUNET_SYSERR;
     }
-    GNUNET_free(expected_pass);
-  }
-  else
-  {
-    GNUNET_free_non_null(basic_authorization);
-    handle->emsg = GNUNET_strdup("server_error");
+    GNUNET_free (expected_pass);
+  } else {
+    GNUNET_free_non_null (basic_authorization);
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
     handle->edesc = GNUNET_strdup ("gnunet configuration failed");
     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
     return GNUNET_SYSERR;
   }
 
-  //check client_id
-  for (handle->ego_entry = handle->ego_head; NULL != handle->ego_entry->next; )
-  {
-    if ( 0 == strcmp(handle->ego_entry->keystring, client_id))
-    {
+  // check client_id
+  for (handle->ego_entry = handle->ego_head; NULL != handle->ego_entry;) {
+    if (0 == strcmp (handle->ego_entry->keystring, client_id)) {
       client_exists = GNUNET_YES;
       break;
     }
     handle->ego_entry = handle->ego_entry->next;
   }
-  if (GNUNET_NO == client_exists)
-  {
-    GNUNET_free_non_null(basic_authorization);
-    handle->emsg=GNUNET_strdup("invalid_client");
+  if (GNUNET_NO == client_exists) {
+    GNUNET_free_non_null (basic_authorization);
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_CLIENT);
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     return GNUNET_SYSERR;
   }
-  GNUNET_STRINGS_string_to_data (client_id,
-                                 strlen(client_id),
-                                 cid,
+  GNUNET_STRINGS_string_to_data (client_id, strlen (client_id), cid,
                                  sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey));
 
   GNUNET_free (basic_authorization);
@@ -1488,13 +1519,11 @@ ego_exists (struct RequestHandle *handle,
   struct EgoEntry *ego_entry;
   struct GNUNET_CRYPTO_EcdsaPublicKey pub_key;
 
-  for (ego_entry = handle->ego_head; NULL != ego_entry; ego_entry = ego_entry->next)
-  {
+  for (ego_entry = handle->ego_head; NULL != ego_entry;
+       ego_entry = ego_entry->next) {
     GNUNET_IDENTITY_ego_get_public_key (ego_entry->ego, &pub_key);
-    if (0 == memcmp (&pub_key,
-                     test_key,
-                     sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey)))
-    {
+    if (0 == memcmp (&pub_key, test_key,
+                     sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey))) {
       break;
     }
   }
@@ -1505,7 +1534,7 @@ ego_exists (struct RequestHandle *handle,
 
 static void
 store_ticket_reference (const struct RequestHandle *handle,
-                        const characcess_token,
+                        const char *access_token,
                         const struct GNUNET_RECLAIM_Ticket *ticket,
                         const struct GNUNET_CRYPTO_EcdsaPublicKey *cid)
 {
@@ -1514,19 +1543,15 @@ store_ticket_reference (const struct RequestHandle *handle,
   char *ticket_string;
   char *client_id;
 
-  GNUNET_CRYPTO_hash(access_token, strlen(access_token), &cache_key);
-  client_id = GNUNET_STRINGS_data_to_string_alloc (cid,
-                                                   sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey));
-  ticket_string = GNUNET_STRINGS_data_to_string_alloc (ticket,
-                                                       sizeof (struct GNUNET_RECLAIM_Ticket));
-  GNUNET_asprintf(&id_ticket_combination,
-                  "%s;%s",
-                  client_id,
-                  ticket_string);
-  GNUNET_CONTAINER_multihashmap_put(OIDC_interpret_access_token,
-                                    &cache_key,
-                                    id_ticket_combination,
-                                    GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE);
+  GNUNET_CRYPTO_hash (access_token, strlen (access_token), &cache_key);
+  client_id = GNUNET_STRINGS_data_to_string_alloc (
+      cid, sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey));
+  ticket_string = GNUNET_STRINGS_data_to_string_alloc (
+      ticket, sizeof (struct GNUNET_RECLAIM_Ticket));
+  GNUNET_asprintf (&id_ticket_combination, "%s;%s", client_id, ticket_string);
+  GNUNET_CONTAINER_multihashmap_put (
+      OIDC_access_token_map, &cache_key, id_ticket_combination,
+      GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE);
 
   GNUNET_free (client_id);
   GNUNET_free (ticket_string);
@@ -1540,13 +1565,12 @@ store_ticket_reference (const struct RequestHandle *handle,
  * @param cls the RequestHandle
  */
 static void
-token_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
-                const char* url,
+token_endpoint (struct GNUNET_REST_RequestHandle *con_handle, const char *url,
                 void *cls)
 {
   struct RequestHandle *handle = cls;
   struct GNUNET_TIME_Relative expiration_time;
-  struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList *cl; 
+  struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList *cl;
   struct GNUNET_RECLAIM_Ticket *ticket;
   struct GNUNET_CRYPTO_EcdsaPublicKey cid;
   struct GNUNET_HashCode cache_key;
@@ -1563,9 +1587,7 @@ token_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
   /*
    * Check Authorization
    */
-  if (GNUNET_SYSERR == check_authorization (handle,
-                                            &cid))
-  {
+  if (GNUNET_SYSERR == check_authorization (handle, &cid)) {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "OIDC authorization for token endpoint failed\n");
     GNUNET_SCHEDULER_add_now (&do_error, handle);
@@ -1576,30 +1598,27 @@ token_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
    * Check parameter
    */
 
-  //TODO Do not allow multiple equal parameter names
-  //REQUIRED grant_type
-  GNUNET_CRYPTO_hash (OIDC_GRANT_TYPE_KEY, strlen (OIDC_GRANT_TYPE_KEY), &cache_key);
-  if (GNUNET_NO ==
-      GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                              &cache_key))
-  {
-    handle->emsg = GNUNET_strdup("invalid_request");
-    handle->edesc = GNUNET_strdup("missing parameter grant_type");
+  // TODO Do not allow multiple equal parameter names
+  // REQUIRED grant_type
+  GNUNET_CRYPTO_hash (OIDC_GRANT_TYPE_KEY, strlen (OIDC_GRANT_TYPE_KEY),
+                      &cache_key);
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->url_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("missing parameter grant_type");
     handle->response_code = MHD_HTTP_BAD_REQUEST;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
-  grant_type = GNUNET_CONTAINER_multihashmap_get (handle->rest_handle->url_param_map,
-                                                  &cache_key);
+  grant_type = GNUNET_CONTAINER_multihashmap_get (
+      handle->rest_handle->url_param_map, &cache_key);
 
-  //REQUIRED code
+  // REQUIRED code
   GNUNET_CRYPTO_hash (OIDC_CODE_KEY, strlen (OIDC_CODE_KEY), &cache_key);
-  if (GNUNET_NO ==
-      GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                              &cache_key))
-  {
-    handle->emsg = GNUNET_strdup("invalid_request");
-    handle->edesc = GNUNET_strdup("missing parameter code");
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->url_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("missing parameter code");
     handle->response_code = MHD_HTTP_BAD_REQUEST;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
@@ -1607,151 +1626,117 @@ token_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
   code = GNUNET_CONTAINER_multihashmap_get (handle->rest_handle->url_param_map,
                                             &cache_key);
 
-  //REQUIRED redirect_uri
+  // REQUIRED redirect_uri
   GNUNET_CRYPTO_hash (OIDC_REDIRECT_URI_KEY, strlen (OIDC_REDIRECT_URI_KEY),
                       &cache_key);
-  if (GNUNET_NO ==
-      GNUNET_CONTAINER_multihashmap_contains (handle->rest_handle->url_param_map,
-                                              &cache_key) )
-  {
-    handle->emsg = GNUNET_strdup("invalid_request");
-    handle->edesc = GNUNET_strdup("missing parameter redirect_uri");
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->url_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("missing parameter redirect_uri");
     handle->response_code = MHD_HTTP_BAD_REQUEST;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
 
-  //Check parameter grant_type == "authorization_code"
-  if (0 != strcmp(OIDC_GRANT_TYPE_VALUE, grant_type))
-  {
-    handle->emsg=GNUNET_strdup("unsupported_grant_type");
+  // Check parameter grant_type == "authorization_code"
+  if (0 != strcmp (OIDC_GRANT_TYPE_VALUE, grant_type)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_UNSUPPORTED_GRANT_TYPE);
     handle->response_code = MHD_HTTP_BAD_REQUEST;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
   GNUNET_CRYPTO_hash (code, strlen (code), &cache_key);
-  if (GNUNET_SYSERR ==
-      GNUNET_CONTAINER_multihashmap_put (OIDC_ticket_once,
-                                         &cache_key,
-                                         &i,
-                                         GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY) )
-  {
-    handle->emsg = GNUNET_strdup("invalid_request");
-    handle->edesc = GNUNET_strdup("Cannot use the same code more than once");
+  if (GNUNET_SYSERR == GNUNET_CONTAINER_multihashmap_put (
+                           OIDC_used_ticket_map, &cache_key, &i,
+                           GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("Cannot use the same code more than once");
     handle->response_code = MHD_HTTP_BAD_REQUEST;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
 
-  //decode code
-  if(GNUNET_OK != OIDC_parse_authz_code (&cid,
-                                         code,
-                                         &ticket,
-                                         &nonce))
-  {
-    handle->emsg = GNUNET_strdup("invalid_request");
-    handle->edesc = GNUNET_strdup("invalid code");
+  // decode code
+  if (GNUNET_OK != OIDC_parse_authz_code (&cid, code, &ticket, &nonce)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("invalid code");
     handle->response_code = MHD_HTTP_BAD_REQUEST;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
     return;
   }
 
-  //create jwt
+  // create jwt
   if (GNUNET_OK !=
-      GNUNET_CONFIGURATION_get_value_time(cfg,
-                                          "reclaim-rest-plugin",
-                                          "expiration_time",
-                                          &expiration_time))
-  {
-    handle->emsg = GNUNET_strdup("server_error");
+      GNUNET_CONFIGURATION_get_value_time (
+          cfg, "reclaim-rest-plugin", "expiration_time", &expiration_time)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_SERVER_ERROR);
     handle->edesc = GNUNET_strdup ("gnunet configuration failed");
     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
-    GNUNET_free(ticket);
+    GNUNET_free (ticket);
     return;
   }
 
 
-  //TODO OPTIONAL acr,amr,azp
-  if (GNUNET_NO == ego_exists (handle,
-                               &ticket->audience))
-  {
-    handle->emsg = GNUNET_strdup("invalid_request");
-    handle->edesc = GNUNET_strdup("invalid code...");
+  // TODO OPTIONAL acr,amr,azp
+  if (GNUNET_NO == ego_exists (handle, &ticket->audience)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("invalid code...");
     handle->response_code = MHD_HTTP_BAD_REQUEST;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
-    GNUNET_free(ticket);
-  }
-  if ( GNUNET_OK
-       != GNUNET_CONFIGURATION_get_value_string (cfg, "reclaim-rest-plugin",
-                                                 "jwt_secret", &jwt_secret) )
-  {
-    handle->emsg = GNUNET_strdup("invalid_request");
-    handle->edesc = GNUNET_strdup("No signing secret configured!");
+    GNUNET_free (ticket);
+  }
+  if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_string (
+                       cfg, "reclaim-rest-plugin", "jwt_secret", &jwt_secret)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_REQUEST);
+    handle->edesc = GNUNET_strdup ("No signing secret configured!");
     handle->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
-    GNUNET_free(ticket);
+    GNUNET_free (ticket);
     return;
   }
-  //TODO We should collect the attributes here. cl always empty
+  // TODO We should collect the attributes here. cl always empty
   cl = GNUNET_new (struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList);
-  id_token = OIDC_id_token_new (&ticket->audience,
-                                &ticket->identity,
-                                cl,
+  id_token = OIDC_id_token_new (&ticket->audience, &ticket->identity, cl,
                                 &expiration_time,
-                                (NULL != nonce) ? nonce : NULL,
-                                jwt_secret);
-  access_token = OIDC_access_token_new (); 
-  OIDC_build_token_response (access_token,
-                             id_token,
-                             &expiration_time,
+                                (NULL != nonce) ? nonce : NULL, jwt_secret);
+  access_token = OIDC_access_token_new ();
+  OIDC_build_token_response (access_token, id_token, &expiration_time,
                              &json_response);
 
-  store_ticket_reference (handle,
-                          access_token,
-                          ticket,
-                          &cid);
+  store_ticket_reference (handle, access_token, ticket, &cid);
   resp = GNUNET_REST_create_response (json_response);
   MHD_add_response_header (resp, "Cache-Control", "no-store");
   MHD_add_response_header (resp, "Pragma", "no-cache");
   MHD_add_response_header (resp, "Content-Type", "application/json");
   handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
-  GNUNET_RECLAIM_ATTRIBUTE_list_destroy(cl);
-  GNUNET_free(access_token);
-  GNUNET_free(json_response);
-  GNUNET_free(ticket);
-  GNUNET_free(id_token);
-  GNUNET_SCHEDULER_add_now(&cleanup_handle_delayed, handle);
+  GNUNET_RECLAIM_ATTRIBUTE_list_destroy (cl);
+  GNUNET_free (access_token);
+  GNUNET_free (json_response);
+  GNUNET_free (ticket);
+  GNUNET_free (id_token);
+  GNUNET_SCHEDULER_add_now (&cleanup_handle_delayed, handle);
 }
 
 /**
  * Collects claims and stores them in handle
  */
 static void
-consume_ticket (void *cls,
-                const struct GNUNET_CRYPTO_EcdsaPublicKey *identity,
+consume_ticket (void *cls, const struct GNUNET_CRYPTO_EcdsaPublicKey *identity,
                 const struct GNUNET_RECLAIM_ATTRIBUTE_Claim *attr)
 {
   struct RequestHandle *handle = cls;
   char *tmp_value;
   json_t *value;
 
-  if (NULL == identity)
-  {
+  if (NULL == identity) {
     GNUNET_SCHEDULER_add_now (&return_userinfo_response, handle);
     return;
   }
-
-  tmp_value = GNUNET_RECLAIM_ATTRIBUTE_value_to_string (attr->type,
-                                                        attr->data,
+  tmp_value = GNUNET_RECLAIM_ATTRIBUTE_value_to_string (attr->type, attr->data,
                                                         attr->data_size);
-
   value = json_string (tmp_value);
-
-
-  json_object_set_new (handle->oidc->response,
-                       attr->name,
-                       value);
+  json_object_set_new (handle->oidc->response, attr->name, value);
   GNUNET_free (tmp_value);
 }
 
@@ -1764,9 +1749,9 @@ consume_ticket (void *cls,
  */
 static void
 userinfo_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
-                   const charurl, void *cls)
+                   const char *url, void *cls)
 {
-  //TODO expiration time
+  // TODO expiration time
   struct RequestHandle *handle = cls;
   char delimiter[] = " ";
   char delimiter_db[] = ";";
@@ -1776,131 +1761,113 @@ userinfo_endpoint (struct GNUNET_REST_RequestHandle *con_handle,
   struct GNUNET_RECLAIM_Ticket *ticket;
 
   GNUNET_CRYPTO_hash (OIDC_AUTHORIZATION_HEADER_KEY,
-                      strlen (OIDC_AUTHORIZATION_HEADER_KEY),
-                      &cache_key);
-  if ( GNUNET_NO
-       == GNUNET_CONTAINER_multihashmap_contains (
-                                                  handle->rest_handle->header_param_map, &cache_key) )
-  {
-    handle->emsg = GNUNET_strdup("invalid_token");
-    handle->edesc = GNUNET_strdup("No Access Token");
+                      strlen (OIDC_AUTHORIZATION_HEADER_KEY), &cache_key);
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       handle->rest_handle->header_param_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
+    handle->edesc = GNUNET_strdup ("No Access Token");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
     return;
   }
   authorization = GNUNET_CONTAINER_multihashmap_get (
-                                                     handle->rest_handle->header_param_map, &cache_key);
+      handle->rest_handle->header_param_map, &cache_key);
 
-  //split header in "Bearer" and access_token
-  authorization = GNUNET_strdup(authorization);
+  // split header in "Bearer" and access_token
+  authorization = GNUNET_strdup (authorization);
   authorization_type = strtok (authorization, delimiter);
-  if ( 0 != strcmp ("Bearer", authorization_type) )
-  {
-    handle->emsg = GNUNET_strdup("invalid_token");
-    handle->edesc = GNUNET_strdup("No Access Token");
+  if (0 != strcmp ("Bearer", authorization_type)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
+    handle->edesc = GNUNET_strdup ("No Access Token");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
-    GNUNET_free(authorization);
+    GNUNET_free (authorization);
     return;
   }
   authorization_access_token = strtok (NULL, delimiter);
-  if ( NULL == authorization_access_token )
-  {
-    handle->emsg = GNUNET_strdup("invalid_token");
-    handle->edesc = GNUNET_strdup("No Access Token");
+  if (NULL == authorization_access_token) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
+    handle->edesc = GNUNET_strdup ("No Access Token");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
-    GNUNET_free(authorization);
+    GNUNET_free (authorization);
     return;
   }
 
   GNUNET_CRYPTO_hash (authorization_access_token,
-                      strlen (authorization_access_token),
-                      &cache_key);
-  if ( GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (OIDC_interpret_access_token,
-                                                            &cache_key) )
-  {
-    handle->emsg = GNUNET_strdup("invalid_token");
-    handle->edesc = GNUNET_strdup("The Access Token expired");
+                      strlen (authorization_access_token), &cache_key);
+  if (GNUNET_NO == GNUNET_CONTAINER_multihashmap_contains (
+                       OIDC_access_token_map, &cache_key)) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
+    handle->edesc = GNUNET_strdup ("The Access Token expired");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
-    GNUNET_free(authorization);
+    GNUNET_free (authorization);
     return;
   }
 
-  client_ticket = GNUNET_CONTAINER_multihashmap_get(OIDC_interpret_access_token,
-                                                    &cache_key);
-  client_ticket = GNUNET_strdup(client_ticket);
-  client = strtok(client_ticket,delimiter_db);
-  if (NULL == client)
-  {
-    handle->emsg = GNUNET_strdup("invalid_token");
-    handle->edesc = GNUNET_strdup("The Access Token expired");
+  client_ticket =
+      GNUNET_CONTAINER_multihashmap_get (OIDC_access_token_map, &cache_key);
+  client_ticket = GNUNET_strdup (client_ticket);
+  client = strtok (client_ticket, delimiter_db);
+  if (NULL == client) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
+    handle->edesc = GNUNET_strdup ("The Access Token expired");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
-    GNUNET_free(authorization);
-    GNUNET_free(client_ticket);
+    GNUNET_free (authorization);
+    GNUNET_free (client_ticket);
     return;
   }
   handle->ego_entry = handle->ego_head;
-  for(; NULL != handle->ego_entry; handle->ego_entry = handle->ego_entry->next)
-  {
-    if (0 == strcmp(handle->ego_entry->keystring,client))
-    {
+  for (; NULL != handle->ego_entry;
+       handle->ego_entry = handle->ego_entry->next) {
+    if (0 == strcmp (handle->ego_entry->keystring, client))
       break;
-    }
   }
-  if (NULL == handle->ego_entry)
-  {
-    handle->emsg = GNUNET_strdup("invalid_token");
-    handle->edesc = GNUNET_strdup("The Access Token expired");
+  if (NULL == handle->ego_entry) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
+    handle->edesc = GNUNET_strdup ("The Access Token expired");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
-    GNUNET_free(authorization);
-    GNUNET_free(client_ticket);
+    GNUNET_free (authorization);
+    GNUNET_free (client_ticket);
     return;
   }
-  ticket_str = strtok(NULL, delimiter_db);
-  if (NULL == ticket_str)
-  {
-    handle->emsg = GNUNET_strdup("invalid_token");
-    handle->edesc = GNUNET_strdup("The Access Token expired");
+  ticket_str = strtok (NULL, delimiter_db);
+  if (NULL == ticket_str) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
+    handle->edesc = GNUNET_strdup ("The Access Token expired");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
-    GNUNET_free(authorization);
-    GNUNET_free(client_ticket);
+    GNUNET_free (authorization);
+    GNUNET_free (client_ticket);
     return;
   }
-  ticket = GNUNET_new(struct GNUNET_RECLAIM_Ticket);
-  if ( GNUNET_OK
-       != GNUNET_STRINGS_string_to_data (ticket_str,
-                                         strlen (ticket_str),
-                                         ticket,
-                                         sizeof(struct GNUNET_RECLAIM_Ticket)))
-  {
-    handle->emsg = GNUNET_strdup("invalid_token");
-    handle->edesc = GNUNET_strdup("The Access Token expired");
+  ticket = GNUNET_new (struct GNUNET_RECLAIM_Ticket);
+  if (GNUNET_OK !=
+      GNUNET_STRINGS_string_to_data (ticket_str, strlen (ticket_str), ticket,
+                                     sizeof (struct GNUNET_RECLAIM_Ticket))) {
+    handle->emsg = GNUNET_strdup (OIDC_ERROR_KEY_INVALID_TOKEN);
+    handle->edesc = GNUNET_strdup ("The Access Token expired");
     handle->response_code = MHD_HTTP_UNAUTHORIZED;
     GNUNET_SCHEDULER_add_now (&do_userinfo_error, handle);
-    GNUNET_free(ticket);
-    GNUNET_free(authorization);
-    GNUNET_free(client_ticket);
+    GNUNET_free (ticket);
+    GNUNET_free (authorization);
+    GNUNET_free (client_ticket);
     return;
   }
 
   handle->idp = GNUNET_RECLAIM_connect (cfg);
-  handle->oidc->response = json_object();
-  json_object_set_new( handle->oidc->response, "sub", json_string( handle->ego_entry->keystring));
+  handle->oidc->response = json_object ();
+  json_object_set_new (handle->oidc->response, "sub",
+                       json_string (handle->ego_entry->keystring));
   handle->idp_op = GNUNET_RECLAIM_ticket_consume (
-                                                  handle->idp,
-                                                  GNUNET_IDENTITY_ego_get_private_key (handle->ego_entry->ego),
-                                                  ticket,
-                                                  consume_ticket,
-                                                  handle);
-  GNUNET_free(ticket);
-  GNUNET_free(authorization);
-  GNUNET_free(client_ticket);
-
+      handle->idp, GNUNET_IDENTITY_ego_get_private_key (handle->ego_entry->ego),
+      ticket, consume_ticket, handle);
+  GNUNET_free (ticket);
+  GNUNET_free (authorization);
+  GNUNET_free (client_ticket);
 }
 
 
@@ -1914,22 +1881,18 @@ init_cont (struct RequestHandle *handle)
 {
   struct GNUNET_REST_RequestHandlerError err;
   static const struct GNUNET_REST_RequestHandler handlers[] = {
-    {MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_AUTHORIZE, &authorize_endpoint},
-    {MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_AUTHORIZE, &authorize_endpoint}, //url-encoded
-    {MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_LOGIN, &login_cont},
-    {MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_TOKEN, &token_endpoint },
-    {MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_USERINFO, &userinfo_endpoint },
-    {MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_USERINFO, &userinfo_endpoint },
-    {MHD_HTTP_METHOD_OPTIONS, GNUNET_REST_API_NS_OIDC,
-      &options_cont},
-    GNUNET_REST_HANDLER_END
-  };
-
-  if (GNUNET_NO == GNUNET_REST_handle_request (handle->rest_handle,
-                                               handlers,
-                                               &err,
-                                               handle))
-  {
+      {MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_AUTHORIZE, &authorize_endpoint},
+      {MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_AUTHORIZE,
+       &authorize_endpoint}, // url-encoded
+      {MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_LOGIN, &login_cont},
+      {MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_TOKEN, &token_endpoint},
+      {MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_USERINFO, &userinfo_endpoint},
+      {MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_USERINFO, &userinfo_endpoint},
+      {MHD_HTTP_METHOD_OPTIONS, GNUNET_REST_API_NS_OIDC, &options_cont},
+      GNUNET_REST_HANDLER_END};
+
+  if (GNUNET_NO == GNUNET_REST_handle_request (handle->rest_handle, handlers,
+                                               &err, handle)) {
     handle->response_code = err.error_code;
     GNUNET_SCHEDULER_add_now (&do_error, handle);
   }
@@ -1969,17 +1932,14 @@ init_cont (struct RequestHandle *handle)
  *                   must thus no longer be used
  */
 static void
-list_ego (void *cls,
-          struct GNUNET_IDENTITY_Ego *ego,
-          void **ctx,
+list_ego (void *cls, struct GNUNET_IDENTITY_Ego *ego, void **ctx,
           const char *identifier)
 {
   struct RequestHandle *handle = cls;
   struct EgoEntry *ego_entry;
   struct GNUNET_CRYPTO_EcdsaPublicKey pk;
 
-  if ((NULL == ego) && (ID_REST_STATE_INIT == handle->state))
-  {
+  if ((NULL == ego) && (ID_REST_STATE_INIT == handle->state)) {
     handle->state = ID_REST_STATE_POST_INIT;
     init_cont (handle);
     return;
@@ -1987,16 +1947,17 @@ list_ego (void *cls,
   if (ID_REST_STATE_INIT == handle->state) {
     ego_entry = GNUNET_new (struct EgoEntry);
     GNUNET_IDENTITY_ego_get_public_key (ego, &pk);
-    ego_entry->keystring =
-      GNUNET_CRYPTO_ecdsa_public_key_to_string (&pk);
+    ego_entry->keystring = GNUNET_CRYPTO_ecdsa_public_key_to_string (&pk);
     ego_entry->ego = ego;
     ego_entry->identifier = GNUNET_strdup (identifier);
-    GNUNET_CONTAINER_DLL_insert_tail(handle->ego_head,handle->ego_tail, ego_entry);
+    GNUNET_CONTAINER_DLL_insert_tail (handle->ego_head, handle->ego_tail,
+                                      ego_entry);
     return;
   }
   /* Ego renamed or added */
   if (identifier != NULL) {
-    for (ego_entry = handle->ego_head; NULL != ego_entry; ego_entry = ego_entry->next) {
+    for (ego_entry = handle->ego_head; NULL != ego_entry;
+         ego_entry = ego_entry->next) {
       if (ego_entry->ego == ego) {
         /* Rename */
         GNUNET_free (ego_entry->identifier);
@@ -2008,39 +1969,40 @@ list_ego (void *cls,
       /* Add */
       ego_entry = GNUNET_new (struct EgoEntry);
       GNUNET_IDENTITY_ego_get_public_key (ego, &pk);
-      ego_entry->keystring =
-        GNUNET_CRYPTO_ecdsa_public_key_to_string (&pk);
+      ego_entry->keystring = GNUNET_CRYPTO_ecdsa_public_key_to_string (&pk);
       ego_entry->ego = ego;
       ego_entry->identifier = GNUNET_strdup (identifier);
-      GNUNET_CONTAINER_DLL_insert_tail(handle->ego_head,handle->ego_tail, ego_entry);
+      GNUNET_CONTAINER_DLL_insert_tail (handle->ego_head, handle->ego_tail,
+                                        ego_entry);
     }
   } else {
     /* Delete */
-    for (ego_entry = handle->ego_head; NULL != ego_entry; ego_entry = ego_entry->next) {
+    for (ego_entry = handle->ego_head; NULL != ego_entry;
+         ego_entry = ego_entry->next) {
       if (ego_entry->ego == ego)
         break;
     }
     if (NULL != ego_entry)
-      GNUNET_CONTAINER_DLL_remove(handle->ego_head,handle->ego_tail, ego_entry);
+      GNUNET_CONTAINER_DLL_remove (handle->ego_head, handle->ego_tail,
+                                   ego_entry);
   }
-
 }
 
 static void
-rest_identity_process_request(struct GNUNET_REST_RequestHandle *rest_handle,
-                              GNUNET_REST_ResultProcessor proc,
-                              void *proc_cls)
+rest_identity_process_request (struct GNUNET_REST_RequestHandle *rest_handle,
+                               GNUNET_REST_ResultProcessor proc, void *proc_cls)
 {
   struct RequestHandle *handle = GNUNET_new (struct RequestHandle);
   handle->oidc = GNUNET_new (struct OIDC_Variables);
-  if ( NULL == OIDC_identity_login_time )
-    OIDC_identity_login_time = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
-  if ( NULL == OIDC_identity_grants )
+  if (NULL == OIDC_cookie_jar_map)
+    OIDC_cookie_jar_map = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
+  if (NULL == OIDC_identity_grants)
     OIDC_identity_grants = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
-  if ( NULL == OIDC_ticket_once )
-    OIDC_ticket_once = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
-  if ( NULL == OIDC_interpret_access_token )
-    OIDC_interpret_access_token = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
+  if (NULL == OIDC_used_ticket_map)
+    OIDC_used_ticket_map = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
+  if (NULL == OIDC_access_token_map)
+    OIDC_access_token_map =
+        GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
   handle->response_code = 0;
   handle->timeout = GNUNET_TIME_UNIT_FOREVER_REL;
   handle->proc_cls = proc_cls;
@@ -2049,21 +2011,15 @@ rest_identity_process_request(struct GNUNET_REST_RequestHandle *rest_handle,
   handle->rest_handle = rest_handle;
 
   handle->url = GNUNET_strdup (rest_handle->url);
-  if (handle->url[strlen (handle->url)-1] == '/')
-    handle->url[strlen (handle->url)-1] = '\0';
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Connecting...\n");
-  handle->identity_handle = GNUNET_IDENTITY_connect (cfg,
-                                                     &list_ego,
-                                                     handle);
+  if (handle->url[strlen (handle->url) - 1] == '/')
+    handle->url[strlen (handle->url) - 1] = '\0';
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connecting...\n");
+  handle->identity_handle = GNUNET_IDENTITY_connect (cfg, &list_ego, handle);
   handle->gns_handle = GNUNET_GNS_connect (cfg);
   handle->namestore_handle = GNUNET_NAMESTORE_connect (cfg);
   handle->timeout_task =
-    GNUNET_SCHEDULER_add_delayed (handle->timeout,
-                                  &do_timeout,
-                                  handle);
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Connected\n");
+      GNUNET_SCHEDULER_add_delayed (handle->timeout, &do_timeout, handle);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connected\n");
 }
 
 /**
@@ -2080,23 +2036,19 @@ libgnunet_plugin_rest_openid_connect_init (void *cls)
 
   cfg = cls;
   if (NULL != plugin.cfg)
-    return NULL;                /* can only initialize once! */
+    return NULL; /* can only initialize once! */
   memset (&plugin, 0, sizeof (struct Plugin));
   plugin.cfg = cfg;
   api = GNUNET_new (struct GNUNET_REST_Plugin);
   api->cls = &plugin;
   api->name = GNUNET_REST_API_NS_OIDC;
   api->process_request = &rest_identity_process_request;
-  GNUNET_asprintf (&allow_methods,
-                   "%s, %s, %s, %s, %s",
-                   MHD_HTTP_METHOD_GET,
-                   MHD_HTTP_METHOD_POST,
-                   MHD_HTTP_METHOD_PUT,
-                   MHD_HTTP_METHOD_DELETE,
-                   MHD_HTTP_METHOD_OPTIONS);
+  GNUNET_asprintf (&allow_methods, "%s, %s, %s, %s, %s", MHD_HTTP_METHOD_GET,
+                   MHD_HTTP_METHOD_POST, MHD_HTTP_METHOD_PUT,
+                   MHD_HTTP_METHOD_DELETE, MHD_HTTP_METHOD_OPTIONS);
 
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              _("Identity Provider REST API initialized\n"));
+              _ ("Identity Provider REST API initialized\n"));
   return api;
 }
 
@@ -2116,40 +2068,34 @@ libgnunet_plugin_rest_openid_connect_done (void *cls)
 
   struct GNUNET_CONTAINER_MultiHashMapIterator *hashmap_it;
   void *value = NULL;
-  hashmap_it = GNUNET_CONTAINER_multihashmap_iterator_create (
-                                                              OIDC_identity_login_time);
+  hashmap_it =
+      GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_cookie_jar_map);
   while (GNUNET_YES ==
          GNUNET_CONTAINER_multihashmap_iterator_next (hashmap_it, NULL, value))
-  {
-    if (NULL != value)
-      GNUNET_free(value);
-  }
-  GNUNET_CONTAINER_multihashmap_destroy(OIDC_identity_login_time);
-  hashmap_it = GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_identity_grants);
+    GNUNET_free_non_null (value);
+  GNUNET_CONTAINER_multihashmap_destroy (OIDC_cookie_jar_map);
+
+  hashmap_it =
+      GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_identity_grants);
   while (GNUNET_YES ==
          GNUNET_CONTAINER_multihashmap_iterator_next (hashmap_it, NULL, value))
-  {
-    if (NULL != value)
-      GNUNET_free(value);
-  }
-  GNUNET_CONTAINER_multihashmap_destroy(OIDC_identity_grants);
-  hashmap_it = GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_ticket_once);
+    GNUNET_free_non_null (value);
+  GNUNET_CONTAINER_multihashmap_destroy (OIDC_identity_grants);
+
+  hashmap_it =
+      GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_used_ticket_map);
   while (GNUNET_YES ==
          GNUNET_CONTAINER_multihashmap_iterator_next (hashmap_it, NULL, value))
-  {
-    if (NULL != value)
-      GNUNET_free(value);
-  }
-  GNUNET_CONTAINER_multihashmap_destroy(OIDC_ticket_once);
-  hashmap_it = GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_interpret_access_token);
+    GNUNET_free_non_null (value);
+  GNUNET_CONTAINER_multihashmap_destroy (OIDC_used_ticket_map);
+
+  hashmap_it =
+      GNUNET_CONTAINER_multihashmap_iterator_create (OIDC_access_token_map);
   while (GNUNET_YES ==
          GNUNET_CONTAINER_multihashmap_iterator_next (hashmap_it, NULL, value))
-  {
-    if (NULL != value)
-      GNUNET_free(value);
-  }
-  GNUNET_CONTAINER_multihashmap_destroy(OIDC_interpret_access_token);
-  GNUNET_CONTAINER_multihashmap_iterator_destroy(hashmap_it);
+    GNUNET_free_non_null (value);
+  GNUNET_CONTAINER_multihashmap_destroy (OIDC_access_token_map);
+  GNUNET_CONTAINER_multihashmap_iterator_destroy (hashmap_it);
   GNUNET_free_non_null (allow_methods);
   GNUNET_free (api);
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,