1 files changed, 468 insertions, 0 deletions

diff --git a/src/contrib/service/scalarproduct/scalarproduct_api.c b/src/contrib/service/scalarproduct/scalarproduct_api.c
new file mode 100644
index 000000000..8c667a72e
--- /dev/null
+++ b/src/contrib/service/scalarproduct/scalarproduct_api.c
@@ -0,0 +1,468 @@
+/*
+     This file is part of GNUnet.
+     Copyright (C) 2013, 2014, 2016 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 scalarproduct/scalarproduct_api.c
+ * @brief API for the scalarproduct
+ * @author Christian Fuchs
+ * @author Gaurav Kukreja
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_statistics_service.h"
+#include "gnunet_scalarproduct_service.h"
+#include "gnunet_protocols.h"
+#include "scalarproduct.h"
+
+#define LOG(kind, ...) GNUNET_log_from (kind, "scalarproduct-api", __VA_ARGS__)
+
+
+/**
+ * The abstraction function for our internal callback
+ *
+ * @param h computation handle
+ * @param msg response we got, NULL on errors
+ * @param status processing status code
+ */
+typedef void
+(*GNUNET_SCALARPRODUCT_ResponseMessageHandler) (
+  struct GNUNET_SCALARPRODUCT_ComputationHandle *h,
+  const struct ClientResponseMessage *msg,
+  enum GNUNET_SCALARPRODUCT_ResponseStatus status);
+
+
+/**
+ * A handle returned for each computation
+ */
+struct GNUNET_SCALARPRODUCT_ComputationHandle
+{
+  /**
+   * Our configuration.
+   */
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * Current connection to the scalarproduct service.
+   */
+  struct GNUNET_MQ_Handle *mq;
+
+  /**
+   * Function to call after transmission of the request (Bob).
+   */
+  GNUNET_SCALARPRODUCT_ContinuationWithStatus cont_status;
+
+  /**
+   * Function to call after transmission of the request (Alice).
+   */
+  GNUNET_SCALARPRODUCT_DatumProcessor cont_datum;
+
+  /**
+   * Closure for @e cont_status or @e cont_datum.
+   */
+  void *cont_cls;
+
+  /**
+   * API internal callback for results and failures to be forwarded to
+   * the client.
+   */
+  GNUNET_SCALARPRODUCT_ResponseMessageHandler response_proc;
+
+  /**
+   * The shared session key identifying this computation
+   */
+  struct GNUNET_HashCode key;
+};
+
+
+/**
+ * Called when a response is received from the service. Perform basic
+ * check that the message is well-formed.
+ *
+ * @param cls Pointer to the Master Context
+ * @param message Pointer to the data received in response
+ * @return #GNUNET_OK if @a message is well-formed
+ */
+static int
+check_response (void *cls,
+                const struct ClientResponseMessage *message)
+{
+  if (ntohs (message->header.size) !=
+      ntohl (message->product_length) + sizeof(struct ClientResponseMessage))
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * Handles the STATUS received from the service for a response, does
+ * not contain a payload.  Called when we participate as "Bob" via
+ * #GNUNET_SCALARPRODUCT_accept_computation().
+ *
+ * @param h our Handle
+ * @param msg the response received
+ * @param status the condition the request was terminated with (eg: disconnect)
+ */
+static void
+process_status_message (struct GNUNET_SCALARPRODUCT_ComputationHandle *h,
+                        const struct ClientResponseMessage *msg,
+                        enum GNUNET_SCALARPRODUCT_ResponseStatus status)
+{
+  if (NULL != h->cont_status)
+    h->cont_status (h->cont_cls,
+                    status);
+  GNUNET_SCALARPRODUCT_cancel (h);
+}
+
+
+/**
+ * Called when a response is received from the service. After basic
+ * check, the handler in `h->response_proc` is called. This functions
+ * handles the response to the client which used the API.
+ *
+ * @param cls Pointer to the Master Context
+ * @param message Pointer to the data received in response
+ */
+static void
+handle_response (void *cls,
+                 const struct ClientResponseMessage *message)
+{
+  struct GNUNET_SCALARPRODUCT_ComputationHandle *h = cls;
+  enum GNUNET_SCALARPRODUCT_ResponseStatus status;
+
+  status = (enum GNUNET_SCALARPRODUCT_ResponseStatus) ntohl (message->status);
+  h->response_proc (h,
+                    message,
+                    status);
+}
+
+
+/**
+ * Check if the keys for all given elements are unique.
+ *
+ * @param elements elements to check
+ * @param element_count size of the @a elements array
+ * @return #GNUNET_OK if all keys are unique
+ */
+static int
+check_unique (const struct GNUNET_SCALARPRODUCT_Element *elements,
+              uint32_t element_count)
+{
+  struct GNUNET_CONTAINER_MultiHashMap *map;
+  int ok;
+
+  ok = GNUNET_OK;
+  map = GNUNET_CONTAINER_multihashmap_create (2 * element_count,
+                                              GNUNET_YES);
+  for (uint32_t i = 0; i < element_count; i++)
+    if (GNUNET_OK !=
+        GNUNET_CONTAINER_multihashmap_put (map,
+                                           &elements[i].key,
+                                           map,
+                                           GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  _ ("Keys given to SCALARPRODUCT not unique!\n"));
+      ok = GNUNET_SYSERR;
+    }
+  GNUNET_CONTAINER_multihashmap_destroy (map);
+  return ok;
+}
+
+
+/**
+ * We encountered an error communicating with the set service while
+ * performing a set operation. Report to the application.
+ *
+ * @param cls the `struct GNUNET_SCALARPRODUCT_ComputationHandle`
+ * @param error error code
+ */
+static void
+mq_error_handler (void *cls,
+                  enum GNUNET_MQ_Error error)
+{
+  struct GNUNET_SCALARPRODUCT_ComputationHandle *h = cls;
+
+  LOG (GNUNET_ERROR_TYPE_INFO,
+       "Disconnected from SCALARPRODUCT service.\n");
+  h->response_proc (h,
+                    NULL,
+                    GNUNET_SCALARPRODUCT_STATUS_DISCONNECTED);
+}
+
+
+struct GNUNET_SCALARPRODUCT_ComputationHandle *
+GNUNET_SCALARPRODUCT_accept_computation (
+  const struct GNUNET_CONFIGURATION_Handle *cfg,
+  const struct GNUNET_HashCode *session_key,
+  const struct GNUNET_SCALARPRODUCT_Element *elements,
+  uint32_t element_count,
+  GNUNET_SCALARPRODUCT_ContinuationWithStatus cont,
+  void *cont_cls)
+{
+  struct GNUNET_SCALARPRODUCT_ComputationHandle *h
+    = GNUNET_new (struct GNUNET_SCALARPRODUCT_ComputationHandle);
+  struct GNUNET_MQ_MessageHandler handlers[] = {
+    GNUNET_MQ_hd_var_size (response,
+                           GNUNET_MESSAGE_TYPE_SCALARPRODUCT_RESULT,
+                           struct ClientResponseMessage,
+                           h),
+    GNUNET_MQ_handler_end ()
+  };
+  struct GNUNET_MQ_Envelope *env;
+  struct BobComputationMessage *msg;
+  struct ComputationBobCryptodataMultipartMessage *mmsg;
+  uint32_t size;
+  uint16_t possible;
+  uint16_t todo;
+  uint32_t element_count_transfered;
+
+
+  if (GNUNET_SYSERR == check_unique (elements,
+                                     element_count))
+    return NULL;
+  h->cont_status = cont;
+  h->cont_cls = cont_cls;
+  h->response_proc = &process_status_message;
+  h->cfg = cfg;
+  h->key = *session_key;
+  h->mq = GNUNET_CLIENT_connect (cfg,
+                                 "scalarproduct-bob",
+                                 handlers,
+                                 &mq_error_handler,
+                                 h);
+  if (NULL == h->mq)
+  {
+    /* scalarproduct configuration error */
+    GNUNET_break (0);
+    GNUNET_free (h);
+    return NULL;
+  }
+  possible = (GNUNET_MAX_MESSAGE_SIZE - 1 - sizeof(struct
+                                                   BobComputationMessage))
+             / sizeof(struct GNUNET_SCALARPRODUCT_Element);
+  todo = GNUNET_MIN (possible,
+                     element_count);
+  size = todo * sizeof(struct GNUNET_SCALARPRODUCT_Element);
+  env = GNUNET_MQ_msg_extra (msg,
+                             size,
+                             GNUNET_MESSAGE_TYPE_SCALARPRODUCT_CLIENT_TO_BOB);
+  msg->element_count_total = htonl (element_count);
+  msg->element_count_contained = htonl (todo);
+  msg->session_key = *session_key;
+  GNUNET_memcpy (&msg[1],
+                 elements,
+                 size);
+  element_count_transfered = todo;
+  GNUNET_MQ_send (h->mq,
+                  env);
+  possible = (GNUNET_MAX_MESSAGE_SIZE - 1 - sizeof(*mmsg))
+             / sizeof(struct GNUNET_SCALARPRODUCT_Element);
+  while (element_count_transfered < element_count)
+  {
+    todo = GNUNET_MIN (possible,
+                       element_count - element_count_transfered);
+    size = todo * sizeof(struct GNUNET_SCALARPRODUCT_Element);
+    env = GNUNET_MQ_msg_extra (mmsg,
+                               size,
+                               GNUNET_MESSAGE_TYPE_SCALARPRODUCT_CLIENT_MULTIPART_BOB);
+    mmsg->element_count_contained = htonl (todo);
+    GNUNET_memcpy (&mmsg[1],
+                   &elements[element_count_transfered],
+                   size);
+    element_count_transfered += todo;
+    GNUNET_MQ_send (h->mq,
+                    env);
+  }
+  return h;
+}
+
+
+/**
+ * Handles the RESULT received from the service for a request, should
+ * contain a result MPI value.  Called when we participate as "Alice" via
+ * #GNUNET_SCALARPRODUCT_start_computation().
+ *
+ * @param h our Handle
+ * @param msg Pointer to the response received
+ * @param status the condition the request was terminated with (eg: disconnect)
+ */
+static void
+process_result_message (struct GNUNET_SCALARPRODUCT_ComputationHandle *h,
+                        const struct ClientResponseMessage *msg,
+                        enum GNUNET_SCALARPRODUCT_ResponseStatus status)
+{
+  uint32_t product_len;
+  gcry_mpi_t result = NULL;
+  gcry_error_t rc;
+  gcry_mpi_t num;
+  size_t rsize;
+
+  if (GNUNET_SCALARPRODUCT_STATUS_SUCCESS == status)
+  {
+    result = gcry_mpi_new (0);
+
+    product_len = ntohl (msg->product_length);
+    if (0 < product_len)
+    {
+      rsize = 0;
+      if (0 != (rc = gcry_mpi_scan (&num, GCRYMPI_FMT_STD,
+                                    &msg[1],
+                                    product_len,
+                                    &rsize)))
+      {
+        LOG_GCRY (GNUNET_ERROR_TYPE_ERROR,
+                  "gcry_mpi_scan",
+                  rc);
+        gcry_mpi_release (result);
+        result = NULL;
+        status = GNUNET_SCALARPRODUCT_STATUS_INVALID_RESPONSE;
+      }
+      else
+      {
+        if (0 < (int32_t) ntohl (msg->range))
+          gcry_mpi_add (result, result, num);
+        else
+          gcry_mpi_sub (result, result, num);
+        gcry_mpi_release (num);
+      }
+    }
+  }
+  if (NULL != h->cont_datum)
+    h->cont_datum (h->cont_cls,
+                   status,
+                   result);
+  if (NULL != result)
+    gcry_mpi_release (result);
+  GNUNET_SCALARPRODUCT_cancel (h);
+}
+
+
+struct GNUNET_SCALARPRODUCT_ComputationHandle *
+GNUNET_SCALARPRODUCT_start_computation (
+  const struct GNUNET_CONFIGURATION_Handle *cfg,
+  const struct GNUNET_HashCode *session_key,
+  const struct GNUNET_PeerIdentity *peer,
+  const struct GNUNET_SCALARPRODUCT_Element *elements,
+  uint32_t element_count,
+  GNUNET_SCALARPRODUCT_DatumProcessor cont,
+  void *cont_cls)
+{
+  struct GNUNET_SCALARPRODUCT_ComputationHandle *h
+    = GNUNET_new (struct GNUNET_SCALARPRODUCT_ComputationHandle);
+  struct GNUNET_MQ_MessageHandler handlers[] = {
+    GNUNET_MQ_hd_var_size (response,
+                           GNUNET_MESSAGE_TYPE_SCALARPRODUCT_RESULT,
+                           struct ClientResponseMessage,
+                           h),
+    GNUNET_MQ_handler_end ()
+  };
+  struct GNUNET_MQ_Envelope *env;
+  struct AliceComputationMessage *msg;
+  struct ComputationBobCryptodataMultipartMessage *mmsg;
+  uint32_t size;
+  uint16_t possible;
+  uint16_t todo;
+  uint32_t element_count_transfered;
+
+  if (GNUNET_SYSERR == check_unique (elements,
+                                     element_count))
+    return NULL;
+  h->mq = GNUNET_CLIENT_connect (cfg,
+                                 "scalarproduct-alice",
+                                 handlers,
+                                 &mq_error_handler,
+                                 h);
+  if (NULL == h->mq)
+  {
+    /* misconfigured scalarproduct service */
+    GNUNET_break (0);
+    GNUNET_free (h);
+    return NULL;
+  }
+  h->cont_datum = cont;
+  h->cont_cls = cont_cls;
+  h->response_proc = &process_result_message;
+  h->cfg = cfg;
+  h->key = *session_key;
+
+  possible = (GNUNET_MAX_MESSAGE_SIZE - 1 - sizeof(struct
+                                                   AliceComputationMessage))
+             / sizeof(struct GNUNET_SCALARPRODUCT_Element);
+  todo = GNUNET_MIN (possible,
+                     element_count);
+  size = todo * sizeof(struct GNUNET_SCALARPRODUCT_Element);
+  env = GNUNET_MQ_msg_extra (msg,
+                             size,
+                             GNUNET_MESSAGE_TYPE_SCALARPRODUCT_CLIENT_TO_ALICE);
+  msg->element_count_total = htonl (element_count);
+  msg->element_count_contained = htonl (todo);
+  msg->reserved = htonl (0);
+  msg->peer = *peer;
+  msg->session_key = *session_key;
+  GNUNET_memcpy (&msg[1],
+                 elements,
+                 size);
+  GNUNET_MQ_send (h->mq,
+                  env);
+  element_count_transfered = todo;
+  possible = (GNUNET_MAX_MESSAGE_SIZE - 1 - sizeof(*mmsg))
+             / sizeof(struct GNUNET_SCALARPRODUCT_Element);
+  while (element_count_transfered < element_count)
+  {
+    todo = GNUNET_MIN (possible,
+                       element_count - element_count_transfered);
+    size = todo * sizeof(struct GNUNET_SCALARPRODUCT_Element);
+    env = GNUNET_MQ_msg_extra (mmsg,
+                               size,
+                               GNUNET_MESSAGE_TYPE_SCALARPRODUCT_CLIENT_MULTIPART_ALICE);
+    mmsg->element_count_contained = htonl (todo);
+    GNUNET_memcpy (&mmsg[1],
+                   &elements[element_count_transfered],
+                   size);
+    element_count_transfered += todo;
+    GNUNET_MQ_send (h->mq,
+                    env);
+  }
+  return h;
+}
+
+
+/**
+ * Cancel an ongoing computation or revoke our collaboration offer.
+ * Closes the connection to the service
+ *
+ * @param h computation handle to terminate
+ */
+void
+GNUNET_SCALARPRODUCT_cancel (struct GNUNET_SCALARPRODUCT_ComputationHandle *h)
+{
+  if (NULL != h->mq)
+  {
+    GNUNET_MQ_destroy (h->mq);
+    h->mq = NULL;
+  }
+  GNUNET_free (h);
+}
+
+
+/* end of scalarproduct_api.c */