Imported Upstream version 0.9.2upstream/0.9.2

1 files changed, 369 insertions, 0 deletions

diff --git a/src/transport/transport_api_address_lookup.c b/src/transport/transport_api_address_lookup.c
new file mode 100644
index 0000000..6e03945
--- /dev/null
+++ b/src/transport/transport_api_address_lookup.c
@@ -0,0 +1,369 @@
+/*
+     This file is part of GNUnet.
+     (C) 2009, 2010 Christian Grothoff (and other contributing authors)
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, 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
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file transport/transport_api_address_lookup.c
+ * @brief given a peer id, get all known addresses from transport service
+ *
+ * This api provides the ability to query the transport service about
+ * the status of connections to a specific peer.  Calls back with a
+ * pretty printed string of the address, as formatted by the appropriate
+ * transport plugin, and whether or not the address given is currently
+ * in the 'connected' state (according to the transport service).
+ */
+
+#include "platform.h"
+#include "gnunet_client_lib.h"
+#include "gnunet_arm_service.h"
+#include "gnunet_hello_lib.h"
+#include "gnunet_protocols.h"
+#include "gnunet_server_lib.h"
+#include "gnunet_time_lib.h"
+#include "gnunet_transport_service.h"
+#include "transport.h"
+
+/**
+ * Context for the address lookup.
+ */
+struct GNUNET_TRANSPORT_PeerIterateContext
+{
+  /**
+   * Function to call with the binary address.
+   */
+  GNUNET_TRANSPORT_PeerIterateCallback cb;
+
+  /**
+   * Closure for cb.
+   */
+  void *cb_cls;
+
+  /**
+   * Connection to the service.
+   */
+  struct GNUNET_CLIENT_Connection *client;
+
+  /**
+   * Configuration we use.
+   */
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * When should this operation time out?
+   */
+  struct GNUNET_TIME_Absolute timeout;
+
+  /**
+   * Backoff for reconnect.
+   */
+  struct GNUNET_TIME_Relative backoff;
+  
+  /**
+   * Task ID for reconnect.
+   */
+  GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
+
+  /**
+   * Identity of the peer to monitor.
+   */
+  struct GNUNET_PeerIdentity peer;
+
+  /**
+   * Was this a one-shot request?
+   */
+  int one_shot;
+};
+
+
+/**
+ * Function called with responses from the service.
+ *
+ * @param cls our 'struct GNUNET_TRANSPORT_PeerAddressLookupContext*'
+ * @param msg NULL on timeout or error, otherwise presumably a
+ *        message with the human-readable address
+ */
+static void
+peer_address_response_processor (void *cls,
+                                 const struct GNUNET_MessageHeader *msg);
+
+
+/**
+ * Send our subscription request to the service.
+ *
+ * @param pal_ctx our context
+ */
+static void
+send_request (struct GNUNET_TRANSPORT_PeerIterateContext *pal_ctx)
+{
+  struct AddressIterateMessage msg;
+
+  msg.header.size = htons (sizeof (struct AddressIterateMessage));
+  msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_ITERATE);
+  msg.one_shot = htonl (pal_ctx->one_shot);
+  msg.timeout = GNUNET_TIME_absolute_hton (pal_ctx->timeout);
+  msg.peer = pal_ctx->peer;
+  GNUNET_assert (GNUNET_OK ==
+                 GNUNET_CLIENT_transmit_and_get_response (pal_ctx->client, 
+							  &msg.header,
+                                                          GNUNET_TIME_absolute_get_remaining (pal_ctx->timeout),
+							  GNUNET_YES,
+                                                          &peer_address_response_processor,
+                                                          pal_ctx));
+}
+
+/**
+ * Task run to re-establish the connection.
+ * 
+ * @param cls our 'struct GNUNET_TRANSPORT_PeerAddressLookupContext*'
+ * @param tc scheduler context, unused
+ */
+static void
+do_connect (void *cls,
+	    const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_TRANSPORT_PeerIterateContext *pal_ctx = cls;
+
+  pal_ctx->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+  pal_ctx->client = GNUNET_CLIENT_connect ("transport", pal_ctx->cfg);
+  GNUNET_assert (NULL != pal_ctx->client);
+  send_request (pal_ctx);
+}
+
+
+/**
+ * Cut the existing connection and reconnect.
+ *
+ * @param pal_ctx our context
+ */
+static void
+reconnect (struct GNUNET_TRANSPORT_PeerIterateContext *pal_ctx)
+{
+  GNUNET_assert (GNUNET_NO == pal_ctx->one_shot);
+  GNUNET_CLIENT_disconnect (pal_ctx->client, GNUNET_NO);
+  pal_ctx->client = NULL;
+  pal_ctx->backoff = GNUNET_TIME_relative_max (GNUNET_TIME_UNIT_MILLISECONDS,
+					       GNUNET_TIME_relative_min (GNUNET_TIME_relative_multiply (pal_ctx->backoff, 2),
+									 GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)));
+  pal_ctx->reconnect_task = GNUNET_SCHEDULER_add_delayed (pal_ctx->backoff,
+							  &do_connect,
+							  pal_ctx);
+}
+
+
+/**
+ * Function called with responses from the service.
+ *
+ * @param cls our 'struct GNUNET_TRANSPORT_PeerAddressLookupContext*'
+ * @param msg NULL on timeout or error, otherwise presumably a
+ *        message with the human-readable address
+ */
+static void
+peer_address_response_processor (void *cls,
+                                 const struct GNUNET_MessageHeader *msg)
+{
+  struct GNUNET_TRANSPORT_PeerIterateContext *pal_ctx = cls;
+  struct AddressIterateResponseMessage *air_msg;
+  struct GNUNET_HELLO_Address *address;
+  const char *addr;
+  const char *transport_name;
+  uint16_t size;
+  size_t alen;
+  size_t tlen;
+
+  if (msg == NULL)
+  {
+    if (pal_ctx->one_shot)
+    {
+      pal_ctx->cb (pal_ctx->cb_cls, NULL, NULL);
+      GNUNET_TRANSPORT_peer_get_active_addresses_cancel (pal_ctx);
+    }
+    else
+    {
+      reconnect (pal_ctx);
+    }
+    return;
+  }
+  size = ntohs (msg->size);
+  GNUNET_break (ntohs (msg->type) ==
+                GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_ITERATE_RESPONSE);
+  if (size == sizeof (struct GNUNET_MessageHeader))
+  {
+    /* done! */
+    if (pal_ctx->one_shot)
+    {
+      pal_ctx->cb (pal_ctx->cb_cls, NULL, NULL);
+      GNUNET_TRANSPORT_peer_get_active_addresses_cancel (pal_ctx);
+    }
+    else
+    {
+      reconnect (pal_ctx);
+    }
+    return;
+  }
+
+  if ((size < sizeof (struct AddressIterateResponseMessage)) ||
+      (ntohs (msg->type) !=
+       GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_ITERATE_RESPONSE))
+  {
+    GNUNET_break (0);
+    if (pal_ctx->one_shot)
+    {
+      pal_ctx->cb (pal_ctx->cb_cls, NULL, NULL);
+      GNUNET_TRANSPORT_peer_get_active_addresses_cancel (pal_ctx);
+    }
+    else
+    {
+      reconnect (pal_ctx);
+    }
+    return;
+  }
+
+  air_msg = (struct AddressIterateResponseMessage *) msg;
+  tlen = ntohl (air_msg->pluginlen);
+  alen = ntohl (air_msg->addrlen);
+
+  if (size != sizeof (struct AddressIterateResponseMessage) + tlen + alen)
+  {
+    GNUNET_break (0);
+    if (pal_ctx->one_shot)
+    {
+      pal_ctx->cb (pal_ctx->cb_cls, NULL, NULL);
+      GNUNET_TRANSPORT_peer_get_active_addresses_cancel (pal_ctx);
+    }
+    else
+    {
+      reconnect (pal_ctx);
+    }
+    return;
+  }
+
+  if (alen == 0 && tlen == 0)
+  {
+    pal_ctx->cb (pal_ctx->cb_cls, &air_msg->peer, NULL);
+  }
+  else
+  {
+    addr = (const char *) &air_msg[1];
+    transport_name = &addr[alen];
+
+    if (transport_name[tlen - 1] != '\0')
+    {
+      GNUNET_break (0);
+      if (pal_ctx->one_shot)	
+      {
+	pal_ctx->cb (pal_ctx->cb_cls, NULL, NULL);
+	GNUNET_TRANSPORT_peer_get_active_addresses_cancel (pal_ctx);
+      }
+      else
+      {
+	reconnect (pal_ctx);
+      }
+      return;
+    }
+
+    /* notify client */
+    address =
+        GNUNET_HELLO_address_allocate (&air_msg->peer, transport_name, addr,
+                                       alen);
+    pal_ctx->cb (pal_ctx->cb_cls, &air_msg->peer, address);
+    GNUNET_HELLO_address_free (address);
+  }
+
+  /* expect more replies */
+  GNUNET_CLIENT_receive (pal_ctx->client, &peer_address_response_processor,
+                         pal_ctx,
+                         GNUNET_TIME_absolute_get_remaining (pal_ctx->timeout));
+}
+
+
+/**
+ * Return all the known addresses for a specific peer or all peers.
+ * Returns continously all address if one_shot is set to GNUNET_NO
+ *
+ * CHANGE: Returns the address(es) that we are currently using for this
+ * peer.  Upon completion, the 'AddressLookUpCallback' is called one more
+ * time with 'NULL' for the address and the peer.  After this, the operation must no
+ * longer be explicitly cancelled.
+ *
+ * @param cfg configuration to use
+ * @param peer peer identity to look up the addresses of, CHANGE: allow NULL for all (connected) peers
+ * @param one_shot GNUNET_YES to return the current state and then end (with NULL+NULL),
+ *                 GNUNET_NO to monitor the set of addresses used (continuously, must be explicitly cancelled)
+ * @param timeout how long is the lookup allowed to take at most (irrelevant if one_shot is set to GNUNET_NO)
+ * @param peer_address_callback function to call with the results
+ * @param peer_address_callback_cls closure for peer_address_callback
+ */
+struct GNUNET_TRANSPORT_PeerIterateContext *
+GNUNET_TRANSPORT_peer_get_active_addresses (const struct
+                                            GNUNET_CONFIGURATION_Handle *cfg,
+                                            const struct GNUNET_PeerIdentity
+                                            *peer, int one_shot,
+                                            struct GNUNET_TIME_Relative timeout,
+                                            GNUNET_TRANSPORT_PeerIterateCallback
+                                            peer_address_callback,
+                                            void *peer_address_callback_cls)
+{
+  struct GNUNET_TRANSPORT_PeerIterateContext *pal_ctx;
+  struct GNUNET_CLIENT_Connection *client;
+
+  client = GNUNET_CLIENT_connect ("transport", cfg);
+  if (client == NULL)
+    return NULL;
+  if (GNUNET_YES != one_shot)
+    timeout = GNUNET_TIME_UNIT_FOREVER_REL;
+  pal_ctx = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PeerIterateContext));
+  pal_ctx->cb = peer_address_callback;
+  pal_ctx->cb_cls = peer_address_callback_cls;
+  pal_ctx->cfg = cfg;
+  pal_ctx->timeout = GNUNET_TIME_relative_to_absolute (timeout);
+  if (NULL != peer)
+    pal_ctx->peer = *peer;
+  pal_ctx->one_shot = one_shot;  
+  pal_ctx->client = client;
+  send_request (pal_ctx);
+
+  return pal_ctx;
+}
+
+
+/**
+ * Cancel request for address conversion.
+ *
+ * @param alc handle for the request to cancel
+ */
+void
+GNUNET_TRANSPORT_peer_get_active_addresses_cancel (struct
+                                                   GNUNET_TRANSPORT_PeerIterateContext
+                                                   *alc)
+{
+  if (NULL != alc->client)
+  {
+    GNUNET_CLIENT_disconnect (alc->client, GNUNET_NO);
+    alc->client = NULL;
+  }
+  if (GNUNET_SCHEDULER_NO_TASK != alc->reconnect_task)
+  {
+    GNUNET_SCHEDULER_cancel (alc->reconnect_task);
+    alc->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+  }
+  GNUNET_free (alc);
+}
+
+
+/* end of transport_api_peer_address_lookup.c */