shell for dv plugin and service, not yet working

1 files changed, 400 insertions, 0 deletions

diff --git a/src/dv/plugin_transport_dv.c b/src/dv/plugin_transport_dv.c
new file mode 100644
index 000000000..aa25c97e6
--- /dev/null
+++ b/src/dv/plugin_transport_dv.c
@@ -0,0 +1,400 @@
+/*
+     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 2, 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/plugin_transport_dv.c
+ * @brief DV transport service, takes incoming DV requests and deals with
+ * the DV service
+ * @author Christian Grothoff
+ */
+
+/**
+ * TODO:
+ *
+ * As a start, the dv plugin needs to listen for information from the dv
+ * service.  The plugin (?) will be notified by core (?) when a tcp/udp/whatever
+ * message comes in that should be for dv.  The plugin will then hand off the message
+ * to the dv service which will decrypt/validate the message (?) and then send the
+ * result back to us (the transport) which will then send the message to the transport
+ * service (yikes).
+ *
+ * Or, core will notify the dv service directly which will validate,
+ * etc. and then just send a message to us.
+ *
+ * For starters, this plugin needs to have a client which will listen for messages from
+ * the dv service that need to be sent up to the gnunet-transport-service.
+ *
+ * Messages sent from the dv transport get passed to the dv service which deals
+ * with the actual sending (how much state does this transport need? should it know
+ * which peers it is currently connected to and their distances, or just assume that
+ * anything should be passed along to the dv service?).
+ */
+#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 "../transport/plugin_transport.h"
+#include "dv.h"
+
+#define DEBUG_TEMPLATE GNUNET_NO
+
+/**
+ * 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;
+
+  /**
+   * Handle for the statistics service.
+   */
+  struct GNUNET_STATISTICS_Handle *statistics;
+
+  /**
+   * 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;
+
+};
+
+
+void handle_dv_message_received (void *cls,
+                                 struct GNUNET_PeerIdentity *sender,
+                                 struct GNUNET_MessageHeader *msg,
+                                 unsigned int distance,
+                                 char *sender_address,
+                                 size_t sender_address_len)
+{
+  struct Plugin *plugin = cls;
+
+  plugin->env->receive(plugin,
+                       sender,
+                       msg,
+                       distance,
+                       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 target who should receive this message
+ * @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 addr the address to use (can be NULL if the plugin
+ *                is "on its own" (i.e. re-use existing TCP connection))
+ * @param addrlen length of the address in bytes
+ * @param force_address GNUNET_YES if the plugin MUST use the given address,
+ *                otherwise the plugin may use other addresses or
+ *                existing connections (if available)
+ * @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,
+                const struct GNUNET_PeerIdentity *target,
+                const char *msgbuf,
+                size_t msgbuf_size,
+                unsigned int priority,
+                struct GNUNET_TIME_Relative timeout,
+                const void *addr,
+                size_t addrlen,
+                int force_address,
+                GNUNET_TRANSPORT_TransmitContinuation
+                cont, void *cont_cls)
+{
+  int ret = 0;
+  struct Plugin *plugin = cls;
+
+  /* FIXME: do we want the dv plugin to remember sent messages to call continuation once message actually goes out?
+   * Or do we just call the continuation once we've notified the plugin?
+   */
+  ret = GNUNET_DV_send(plugin->dv_handle,
+                       target,
+                       msgbuf,
+                       msgbuf_size,
+                       priority,
+                       timeout,
+                       addr,
+                       addrlen);
+  /*, cont, cont_cls);*/
+
+  if (ret == 0)
+    cont(cls, target, GNUNET_OK);
+  else
+    cont(cls, target, GNUNET_SYSERR);
+
+  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;
+  // FIXME
+}
+
+
+/**
+ * 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)
+{
+  asc (asc_cls, NULL);
+}
+
+
+
+/**
+ * Another peer has suggested an address for this
+ * peer and transport plugin.  Check that this could be a valid
+ * address.  If so, consider adding it to the list
+ * of addresses.
+ *
+ * @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
+ *
+ * FIXME: does this mean anything for the DV plugin?
+ */
+static int
+dv_plugin_address_suggested (void *cls,
+                                  void *addr, size_t addrlen)
+{
+  /* struct Plugin *plugin = cls; */
+
+  /* check if the address is plausible; if so,
+     add it to our list! */
+  return GNUNET_OK;
+}
+
+
+/**
+ * Entry point for the plugin.
+ */
+void *
+gnunet_plugin_transport_dv_init (void *cls)
+{
+  struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
+  struct GNUNET_TRANSPORT_PluginFunctions *api;
+  struct Plugin *plugin;
+  unsigned long long port;
+  struct GNUNET_SERVICE_Context *service;
+
+  service = GNUNET_SERVICE_start ("transport-dv", env->sched, env->cfg);
+  if (service == NULL)
+    {
+      GNUNET_log_from (GNUNET_ERROR_TYPE_WARNING,
+                       "dv",
+                       _
+                       ("Failed to start service for `%s' transport plugin.\n"),
+                       "dv");
+      return NULL;
+    }
+
+  if ((GNUNET_OK !=
+       GNUNET_CONFIGURATION_get_value_number (env->cfg,
+                                              "transport-dv",
+                                              "PORT",
+                                              &port)))
+    {
+      GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
+                       "dv",
+                       _
+                       ("Require valid port number for service `%s' in configuration!\n"),
+                       "transport-dv");
+      GNUNET_SERVICE_stop (service);
+      return NULL;
+    }
+
+  plugin = GNUNET_malloc (sizeof (struct Plugin));
+  plugin->env = env;
+  plugin->statistics = NULL;
+  plugin->service = service;
+  plugin->server = GNUNET_SERVICE_get_server (service);
+
+  plugin->dv_handle = GNUNET_DV_connect(env->sched, env->cfg, &handle_dv_message_received, plugin);
+
+  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_address_suggested;
+  return api;
+}
+
+
+/**
+ * Exit point from the plugin.
+ */
+void *
+gnunet_plugin_transport_dv_done (void *cls)
+{
+  struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
+  struct Plugin *plugin = api->cls;
+
+  GNUNET_free (plugin);
+  GNUNET_free (api);
+  return NULL;
+}
+
+/* end of plugin_transport_template.c */