1 files changed, 452 insertions, 0 deletions

diff --git a/src/dv/plugin_transport_dv.c b/src/dv/plugin_transport_dv.c
new file mode 100644
index 0000000..8ee49c5
--- /dev/null
+++ b/src/dv/plugin_transport_dv.c
@@ -0,0 +1,452 @@
+/*
+     This file is part of GNUnet
+     (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 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 dv/plugin_transport_dv.c
+ * @brief DV transport service, takes incoming DV requests and deals with
+ * the DV service
+ * @author Nathan Evans
+ * @author Christian Grothoff
+ */
+
+#include "platform.h"
+#include "gnunet_protocols.h"
+#include "gnunet_connection_lib.h"
+#include "gnunet_server_lib.h"
+#include "gnunet_service_lib.h"
+#include "gnunet_statistics_service.h"
+#include "gnunet_dv_service.h"
+#include "gnunet_transport_service.h"
+#include "gnunet_transport_plugin.h"
+#include "dv.h"
+
+#define DEBUG_TEMPLATE GNUNET_EXTRA_LOGGING
+
+/**
+ * Encapsulation of all of the state of the plugin.
+ */
+struct Plugin;
+
+
+/**
+ * Session handle for connections.
+ */
+struct Session
+{
+
+  /**
+   * Stored in a linked list.
+   */
+  struct Session *next;
+
+  /**
+   * Pointer to the global plugin struct.
+   */
+  struct Plugin *plugin;
+
+  /**
+   * The client (used to identify this connection)
+   */
+  /* void *client; */
+
+  /**
+   * Continuation function to call once the transmission buffer
+   * has again space available.  NULL if there is no
+   * continuation to call.
+   */
+  GNUNET_TRANSPORT_TransmitContinuation transmit_cont;
+
+  /**
+   * Closure for transmit_cont.
+   */
+  void *transmit_cont_cls;
+
+  /**
+   * To whom are we talking to (set to our identity
+   * if we are still waiting for the welcome message)
+   */
+  struct GNUNET_PeerIdentity sender;
+
+  /**
+   * At what time did we reset last_received last?
+   */
+  struct GNUNET_TIME_Absolute last_quota_update;
+
+  /**
+   * How many bytes have we received since the "last_quota_update"
+   * timestamp?
+   */
+  uint64_t last_received;
+
+  /**
+   * Number of bytes per ms that this peer is allowed
+   * to send to us.
+   */
+  uint32_t quota;
+
+};
+
+/**
+ * Encapsulation of all of the state of the plugin.
+ */
+struct Plugin
+{
+  /**
+   * Our environment.
+   */
+  struct GNUNET_TRANSPORT_PluginEnvironment *env;
+
+  /**
+   * List of open sessions.
+   */
+  struct Session *sessions;
+
+  /**
+   * Our server.
+   */
+  //struct GNUNET_SERVER_Handle *server;
+
+  /*
+   * Handle to the running service.
+   */
+  //struct GNUNET_SERVICE_Context *service;
+
+  /**
+   * Copy of the handler array where the closures are
+   * set to this struct's instance.
+   */
+  struct GNUNET_SERVER_MessageHandler *handlers;
+
+  /**
+   * Handle to the DV service
+   */
+  struct GNUNET_DV_Handle *dv_handle;
+
+};
+
+/**
+ * Handler for messages received from the DV service.
+ */
+void
+handle_dv_message_received (void *cls, struct GNUNET_PeerIdentity *sender,
+                            char *msg, size_t msg_len, uint32_t distance,
+                            char *sender_address, size_t sender_address_len)
+{
+  struct Plugin *plugin = cls;
+
+#if DEBUG_DV_MESSAGES
+  char *my_id;
+
+  my_id = GNUNET_strdup (GNUNET_i2s (plugin->env->my_identity));
+  GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "plugin_transport_dv",
+                   _("%s Received message from %s of type %d, distance %u!\n"),
+                   my_id, GNUNET_i2s (sender),
+                   ntohs (((struct GNUNET_MessageHeader *) msg)->type),
+                   distance);
+  if (sender_address_len == (2 * sizeof (struct GNUNET_PeerIdentity)))
+  {
+    GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "plugin_transport_dv",
+                     "Parsed sender address: %s:%s\n",
+                     GNUNET_i2s ((struct GNUNET_PeerIdentity *) sender_address),
+                     GNUNET_h2s (&
+                                 ((struct GNUNET_PeerIdentity *)
+                                  &sender_address[sizeof
+                                                  (struct
+                                                   GNUNET_PeerIdentity)])->hashPubKey));
+  }
+
+  GNUNET_free_non_null (my_id);
+#endif
+  struct GNUNET_ATS_Information ats[1];
+
+  ats[0].type = htonl (GNUNET_ATS_QUALITY_NET_DISTANCE);
+  ats[0].value = htonl (distance);
+
+  plugin->env->receive (plugin->env->cls, sender,
+                        (struct GNUNET_MessageHeader *) msg,
+                        (const struct GNUNET_ATS_Information *) &ats, 1, NULL,
+                        sender_address, sender_address_len);
+
+}
+
+
+/* Question: how does the transport service learn of a newly connected (gossipped about)
+ * DV peer?  Should the plugin (here) create a HELLO for that peer and send it along,
+ * or should the DV service create a HELLO and send it to us via the other part?
+ */
+
+/**
+ * Function that can be used by the transport service to transmit
+ * a message using the plugin.
+ *
+ * @param cls closure
+ * @param session the session used
+ * @param priority how important is the message
+ * @param msgbuf the message to transmit
+ * @param msgbuf_size number of bytes in 'msgbuf'
+ * @param timeout when should we time out
+ * @param cont continuation to call once the message has
+ *        been transmitted (or if the transport is ready
+ *        for the next transmission call; or if the
+ *        peer disconnected...)
+ * @param cont_cls closure for cont
+ * @return number of bytes used (on the physical network, with overheads);
+ *         -1 on hard errors (i.e. address invalid); 0 is a legal value
+ *         and does NOT mean that the message was not transmitted (DV)
+ */
+static ssize_t
+dv_plugin_send (void *cls, 
+		struct Session *session,
+                const char *msgbuf, size_t msgbuf_size, unsigned int priority,
+                struct GNUNET_TIME_Relative timeout, 
+                GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
+{
+  int ret = -1;
+#if 0
+  struct Plugin *plugin = cls;
+
+  ret =
+      GNUNET_DV_send (plugin->dv_handle, &session->sender, 
+		      msgbuf, msgbuf_size, priority,
+                      timeout, addr, addrlen, cont, cont_cls);
+#endif
+  return ret;
+}
+
+
+
+/**
+ * Function that can be used to force the plugin to disconnect
+ * from the given peer and cancel all previous transmissions
+ * (and their continuations).
+ *
+ * @param cls closure
+ * @param target peer from which to disconnect
+ */
+static void
+dv_plugin_disconnect (void *cls, const struct GNUNET_PeerIdentity *target)
+{
+  // struct Plugin *plugin = cls;
+  // TODO: Add message type to send to dv service to "disconnect" a peer
+}
+
+
+/**
+ * Convert the transports address to a nice, human-readable
+ * format.
+ *
+ * @param cls closure
+ * @param type name of the transport that generated the address
+ * @param addr one of the addresses of the host, NULL for the last address
+ *        the specific address format depends on the transport
+ * @param addrlen length of the address
+ * @param numeric should (IP) addresses be displayed in numeric form?
+ * @param timeout after how long should we give up?
+ * @param asc function to call on each string
+ * @param asc_cls closure for asc
+ */
+static void
+dv_plugin_address_pretty_printer (void *cls, const char *type, const void *addr,
+                                  size_t addrlen, int numeric,
+                                  struct GNUNET_TIME_Relative timeout,
+                                  GNUNET_TRANSPORT_AddressStringCallback asc,
+                                  void *asc_cls)
+{
+  char *dest_peer;
+  char *via_peer;
+  char *print_string;
+  char *addr_buf = (char *) addr;
+
+  if (addrlen != sizeof (struct GNUNET_PeerIdentity) * 2)
+  {
+    asc (asc_cls, NULL);
+  }
+  else
+  {
+    dest_peer =
+        GNUNET_strdup (GNUNET_i2s ((struct GNUNET_PeerIdentity *) addr));
+    via_peer =
+        GNUNET_strdup (GNUNET_i2s
+                       ((struct GNUNET_PeerIdentity *)
+                        &addr_buf[sizeof (struct GNUNET_PeerIdentity)]));
+    GNUNET_asprintf (&print_string, "DV Peer `%s' via peer`%s'", dest_peer,
+                     via_peer);
+    asc (asc_cls, print_string);
+    asc (asc_cls, NULL);
+    GNUNET_free (via_peer);
+    GNUNET_free (dest_peer);
+    GNUNET_free (print_string);
+  }
+}
+
+/**
+ * Convert the DV address to a pretty string.
+ *
+ * @param cls closure
+ * @param addr the (hopefully) DV address
+ * @param addrlen the length of the address
+ *
+ * @return string representing the DV address
+ */
+static const char *
+address_to_string (void *cls, const void *addr, size_t addrlen)
+{
+  static char return_buffer[2 * 4 + 2]; // Two four character peer identity prefixes a ':' and '\0'
+
+  struct GNUNET_CRYPTO_HashAsciiEncoded peer_hash;
+  struct GNUNET_CRYPTO_HashAsciiEncoded via_hash;
+  struct GNUNET_PeerIdentity *peer;
+  struct GNUNET_PeerIdentity *via;
+  char *addr_buf = (char *) addr;
+
+  if (addrlen == (2 * sizeof (struct GNUNET_PeerIdentity)))
+  {
+    peer = (struct GNUNET_PeerIdentity *) addr_buf;
+    via =
+        (struct GNUNET_PeerIdentity *)
+        &addr_buf[sizeof (struct GNUNET_PeerIdentity)];
+
+    GNUNET_CRYPTO_hash_to_enc (&peer->hashPubKey, &peer_hash);
+    peer_hash.encoding[4] = '\0';
+    GNUNET_CRYPTO_hash_to_enc (&via->hashPubKey, &via_hash);
+    via_hash.encoding[4] = '\0';
+    GNUNET_snprintf (return_buffer, sizeof (return_buffer), "%s:%s", &peer_hash,
+                     &via_hash);
+  }
+  else
+    return NULL;
+
+  return return_buffer;
+}
+
+/**
+ * Another peer has suggested an address for this peer and transport
+ * plugin.  Check that this could be a valid address.  This function
+ * is not expected to 'validate' the address in the sense of trying to
+ * connect to it but simply to see if the binary format is technically
+ * legal for establishing a connection to this peer (and make sure that
+ * the address really corresponds to our network connection/settings
+ * and not some potential man-in-the-middle).
+ *
+ * @param cls closure
+ * @param addr pointer to the address
+ * @param addrlen length of addr
+ * @return GNUNET_OK if this is a plausible address for this peer
+ *         and transport, GNUNET_SYSERR if not
+ *
+ */
+static int
+dv_plugin_check_address (void *cls, const void *addr, size_t addrlen)
+{
+  struct Plugin *plugin = cls;
+
+  /* Verify that the first peer of this address matches our peer id! */
+  if ((addrlen != (2 * sizeof (struct GNUNET_PeerIdentity))) ||
+      (0 !=
+       memcmp (addr, plugin->env->my_identity,
+               sizeof (struct GNUNET_PeerIdentity))))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "%s: Address not correct size or identity doesn't match ours!\n",
+                GNUNET_i2s (plugin->env->my_identity));
+    if (addrlen == (2 * sizeof (struct GNUNET_PeerIdentity)))
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer in address is %s\n",
+                  GNUNET_i2s (addr));
+    }
+    return GNUNET_SYSERR;
+  }
+
+  return GNUNET_OK;
+}
+
+
+
+/**
+ * Create a new session to transmit data to the target
+ * This session will used to send data to this peer and the plugin will
+ * notify us by calling the env->session_end function
+ *
+ * @param cls the plugin
+ * @param target the neighbour id
+ * @param addr pointer to the address
+ * @param addrlen length of addr
+ * @return the session if the address is valid, NULL otherwise
+ */
+static struct Session * 
+dv_get_session (void *cls,
+		const struct GNUNET_HELLO_Address *address)
+{
+  return NULL;
+}
+
+
+/**
+ * Entry point for the plugin.
+ */
+void *
+libgnunet_plugin_transport_dv_init (void *cls)
+{
+  struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
+  struct GNUNET_TRANSPORT_PluginFunctions *api;
+  struct Plugin *plugin;
+
+  plugin = GNUNET_malloc (sizeof (struct Plugin));
+  plugin->env = env;
+
+  plugin->dv_handle =
+      GNUNET_DV_connect (env->cfg, &handle_dv_message_received, plugin);
+
+  if (plugin->dv_handle == NULL)
+  {
+    GNUNET_free (plugin);
+    return NULL;
+  }
+
+  api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
+  api->cls = plugin;
+  api->send = &dv_plugin_send;
+  api->disconnect = &dv_plugin_disconnect;
+  api->address_pretty_printer = &dv_plugin_address_pretty_printer;
+  api->check_address = &dv_plugin_check_address;
+  api->address_to_string = &address_to_string;
+  api->get_session = dv_get_session;
+  return api;
+}
+
+
+/**
+ * Exit point from the plugin.
+ */
+void *
+libgnunet_plugin_transport_dv_done (void *cls)
+{
+  struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
+  struct Plugin *plugin = api->cls;
+
+  if (plugin->dv_handle != NULL)
+    GNUNET_DV_disconnect (plugin->dv_handle);
+
+  GNUNET_free (plugin);
+  GNUNET_free (api);
+  return NULL;
+}
+
+/* end of plugin_transport_dv.c */