1 files changed, 265 insertions, 0 deletions

diff --git a/src/service/reclaim/did_core.c b/src/service/reclaim/did_core.c
new file mode 100644
index 000000000..ce3336b91
--- /dev/null
+++ b/src/service/reclaim/did_core.c
@@ -0,0 +1,265 @@
+/*
+   This file is part of GNUnet
+   Copyright (C) 2010-2015 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
+   by the Free Software Foundation, either version 3 of the License,
+   or (at your option) any later version.
+
+   GNUnet is distributed in the hope that it will be useful, but
+   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
+ */
+
+/**
+ * @file reclaim/did_core.c
+ * @brief Core functionality for DID
+ * @author Tristan Schwieren
+ */
+
+// TODO: DID documents do not have an expiration date. Still we add one
+// TODO: Store DID document with empty label and own type (maybe DID-Document or JSON??)
+
+#include "platform.h"
+#include "did_core.h"
+
+struct DID_resolve_return
+{
+  DID_resolve_callback *cb;
+  void *cls;
+};
+
+struct DID_action_return
+{
+  DID_action_callback *cb;
+  void *cls;
+};
+
+// ------------------------------------------------ //
+// -------------------- Resolve ------------------- //
+// ------------------------------------------------ //
+
+/**
+ * @brief GNS lookup callback. Calls the given callback function
+ * and gives it the DID Document.
+ * Fails if there is more than one DID record.
+ *
+ * @param cls closure
+ * @param rd_count number of records in rd
+ * @param rd the records in the reply
+ */
+static void
+DID_resolve_gns_lookup_cb (
+  void *cls,
+  uint32_t rd_count,
+  const struct GNUNET_GNSRECORD_Data *rd)
+{
+  char *did_document;
+  DID_resolve_callback *cb = ((struct DID_resolve_return *) cls)->cb;
+  void *cls_did_resolve_cb = ((struct DID_resolve_return *) cls)->cls;
+  free (cls);
+
+  for (int i = 0; i < rd_count; i++) {
+    if (rd[i].record_type != GNUNET_GNSRECORD_TYPE_DID_DOCUMENT)
+      continue;
+    did_document = (char *) rd[i].data;
+    cb (GNUNET_OK, did_document, cls_did_resolve_cb);
+    return;
+  }
+  cb (GNUNET_NO, "DID Document is not a DID_DOCUMENT record\n",
+      cls_did_resolve_cb);
+}
+
+/**
+ * @brief Resolve a DID.
+ * Calls the given callback function with the resolved DID Document and the given closure.
+ * If the did can not be resolved did_document is NULL.
+ *
+ * @param did DID that is resolve
+ */
+enum GNUNET_GenericReturnValue
+DID_resolve (const char *did,
+             struct GNUNET_GNS_Handle *gns_handle,
+             DID_resolve_callback *cont,
+             void *cls)
+{
+  struct GNUNET_CRYPTO_PublicKey pkey;
+
+  // did, gns_handle and cont must me set
+  if ((did == NULL) || (gns_handle == NULL) || (cont == NULL))
+    return GNUNET_NO;
+
+  if (GNUNET_OK != DID_did_to_pkey (did, &pkey))
+    return GNUNET_NO;
+
+  // Create closure for lookup callback
+  struct DID_resolve_return *cls_gns_lookup_cb
+    = malloc (sizeof(struct DID_resolve_return));
+  cls_gns_lookup_cb->cb = cont;
+  cls_gns_lookup_cb->cls = cls;
+
+  GNUNET_GNS_lookup (gns_handle,
+                     DID_DOCUMENT_LABEL,
+                     &pkey,
+                     GNUNET_GNSRECORD_TYPE_DID_DOCUMENT,
+                     GNUNET_GNS_LO_DEFAULT,
+                     &DID_resolve_gns_lookup_cb,
+                     cls_gns_lookup_cb);
+
+  return GNUNET_OK;
+}
+
+// ------------------------------------------------ //
+// -------------------- Create -------------------- //
+// ------------------------------------------------ //
+
+static void
+DID_create_did_store_cb (void *cls,
+                         enum GNUNET_ErrorCode ec)
+{
+  DID_action_callback *cb = ((struct DID_action_return *) cls)->cb;
+  void *cls_did_create_cb = ((struct DID_action_return *) cls)->cls;
+  free (cls);
+
+  if (GNUNET_EC_NONE == ec)
+  {
+    cb (GNUNET_OK, (void *) cls_did_create_cb);
+  }
+  else
+  {
+    // TODO: Log emsg. Not writing it to STDOUT
+    printf ("%s\n", GNUNET_ErrorCode_get_hint (ec));
+    cb (GNUNET_NO, (void *) cls_did_create_cb);
+  }
+}
+
+struct DID_create_namestore_lookup_closure
+{
+  const char *did_document;
+  struct GNUNET_TIME_Relative expire_time;
+  struct GNUNET_NAMESTORE_Handle *namestore_handle;
+  struct DID_action_return *ret;
+};
+
+static void
+DID_create_namestore_lookup_cb (void *cls,
+                                const struct
+                                GNUNET_CRYPTO_PrivateKey *zone,
+                                const char *label,
+                                unsigned int rd_count,
+                                const struct GNUNET_GNSRECORD_Data *rd)
+{
+  struct GNUNET_GNSRECORD_Data record_data;
+  struct GNUNET_CRYPTO_PublicKey pkey;
+
+  const char *did_document
+    = ((struct DID_create_namestore_lookup_closure *) cls)->did_document;
+
+  const struct GNUNET_TIME_Relative expire_time
+    = ((struct DID_create_namestore_lookup_closure *) cls)->expire_time;
+
+  struct GNUNET_NAMESTORE_Handle *namestore_handle
+    = ((struct DID_create_namestore_lookup_closure *) cls)->namestore_handle;
+
+  struct DID_action_return *cls_record_store_cb
+    = ((struct DID_create_namestore_lookup_closure *) cls)->ret;
+
+  free (cls);
+
+  if (rd_count > 0)
+  {
+    printf ("Ego already has a DID Document. Abort.\n");
+    cls_record_store_cb->cb (GNUNET_NO, cls_record_store_cb->cls);
+  }
+  else {
+    // Get public key
+    GNUNET_CRYPTO_key_get_public (zone, &pkey);
+
+    // If no DID Document is given a default one is created
+    if (did_document != NULL)
+      printf (
+        "DID Docuement is read from \"DID-document\" argument (EXPERIMENTAL)\n");
+    else
+      did_document = DID_pkey_to_did_document (&pkey);
+
+    // Create record
+    record_data.data = did_document;
+    record_data.expiration_time = expire_time.rel_value_us;
+    record_data.data_size = strlen (did_document) + 1;
+    record_data.record_type = GNUNET_GNSRECORD_typename_to_number ("TXT"),
+    record_data.flags = GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION;
+
+    // Store record
+    GNUNET_NAMESTORE_records_store (namestore_handle,
+                                    zone,
+                                    DID_DOCUMENT_LABEL,
+                                    1, // FIXME what if GNUNET_GNS_EMPTY_LABEL_AT has records
+                                    &record_data,
+                                    &DID_create_did_store_cb,
+                                    (void *) cls_record_store_cb);
+  }
+}
+
+/**
+ * @brief Creates a DID and saves DID Document in Namestore.
+ *
+ * @param ego ego for which the DID should be created.
+ * @param did_document did_document that should be saved in namestore.
+ * If did_document==NULL -> Default DID document is created.
+ * @param namestore_handle
+ * @param cont callback function
+ * @param cls closure
+ */
+enum GNUNET_GenericReturnValue
+DID_create (const struct GNUNET_IDENTITY_Ego *ego,
+            const char *did_document,
+            const struct GNUNET_TIME_Relative *expire_time,
+            struct GNUNET_NAMESTORE_Handle *namestore_handle,
+            DID_action_callback *cont,
+            void *cls)
+{
+  struct GNUNET_CRYPTO_PublicKey pkey;
+
+  // Ego, namestore_handle and cont must be set
+  if ((ego == NULL) || (namestore_handle == NULL) || (cont == NULL))
+    return GNUNET_NO;
+
+  // Check if ego has EdDSA key
+  GNUNET_IDENTITY_ego_get_public_key ((struct GNUNET_IDENTITY_Ego *) ego,
+                                      &pkey);
+  if (ntohl (pkey.type) != GNUNET_GNSRECORD_TYPE_EDKEY)
+  {
+    printf ("The EGO has to have an EdDSA key pair\n");
+    return GNUNET_NO;
+  }
+
+  struct DID_action_return *ret
+    = malloc (sizeof(struct DID_action_return));
+  ret->cb = cont;
+  ret->cls = cls;
+
+  struct DID_create_namestore_lookup_closure *cls_name_store_lookup_cb
+    = malloc (sizeof(struct DID_create_namestore_lookup_closure));
+  cls_name_store_lookup_cb->did_document = did_document;
+  cls_name_store_lookup_cb->expire_time = (*expire_time);
+  cls_name_store_lookup_cb->namestore_handle = namestore_handle;
+  cls_name_store_lookup_cb->ret = ret;
+
+  // Check if ego already has a DID Document
+  GNUNET_NAMESTORE_records_lookup (namestore_handle,
+                                   GNUNET_IDENTITY_ego_get_private_key (ego),
+                                   DID_DOCUMENT_LABEL,
+                                   NULL,
+                                   NULL,
+                                   DID_create_namestore_lookup_cb,
+                                   (void *) cls_name_store_lookup_cb);
+
+  return GNUNET_OK;
+}