1 files changed, 253 insertions, 33 deletions

diff --git a/src/dht/gnunet-service-dht.c b/src/dht/gnunet-service-dht.c
index da46dcfee..6f2573d26 100644
--- a/src/dht/gnunet-service-dht.c
+++ b/src/dht/gnunet-service-dht.c
@@ -27,8 +27,6 @@
 #include "platform.h"
 #include "gnunet_block_lib.h"
 #include "gnunet_util_lib.h"
-#include "gnunet_transport_service.h"
-#include "gnunet_transport_hello_service.h"
 #include "gnunet_hello_lib.h"
 #include "gnunet_dht_service.h"
 #include "gnunet_statistics_service.h"
@@ -36,44 +34,223 @@
 #include "gnunet-service-dht_datacache.h"
 #include "gnunet-service-dht_hello.h"
 #include "gnunet-service-dht_neighbours.h"
-#include "gnunet-service-dht_nse.h"
 #include "gnunet-service-dht_routing.h"
 
+
+/**
+ * Information we keep per underlay.
+ */
+struct Underlay
+{
+
+  /**
+   * Kept in a DLL.
+   */
+  struct Underlay *next;
+
+  /**
+   * Kept in a DLL.
+   */
+  struct Underlay *prev;
+
+  /**
+   * Environment for this underlay.
+   */
+  struct GNUNET_DHTU_PluginEnvironment env;
+
+  /**
+   * Underlay API handle.
+   */
+  struct GNUNET_DHTU_PluginFunctions *dhtu;
+
+  /**
+   * current network size estimate for this underlay.
+   */
+  double network_size_estimate;
+
+  /**
+   * Name of the underlay (i.e. "gnunet" or "ip").
+   */
+  char *name;
+};
+
+
+/**
+ * An address of this peer.
+ */
+struct MyAddress
+{
+  /**
+   * Kept in a DLL.
+   */
+  struct MyAddress *next;
+
+  /**
+   * Kept in a DLL.
+   */
+  struct MyAddress *prev;
+
+  /**
+   * Underlay handle for the address.
+   */
+  struct GNUNET_DHTU_Source *source;
+
+  /**
+   * Textual representation of the address.
+   */
+  char *url;
+
+  /**
+   * Underlay of this address.
+   */
+  struct Underlay *u;
+};
+
+
 /**
  * Our HELLO
  */
 struct GNUNET_MessageHeader *GDS_my_hello;
 
 /**
- * Handle to get our current HELLO.
+ * Handles for the DHT underlays.
+ */
+static struct Underlay *u_head;
+
+/**
+ * Handles for the DHT underlays.
+ */
+static struct Underlay *u_tail;
+
+/**
+ * Head of addresses of this peer.
+ */
+static struct MyAddress *a_head;
+
+/**
+ * Tail of addresses of this peer.
  */
-static struct GNUNET_TRANSPORT_HelloGetHandle *ghh;
+static struct MyAddress *a_tail;
 
 /**
  * Hello address expiration
  */
 struct GNUNET_TIME_Relative hello_expiration;
 
+/**
+ * log of the current network size estimate, used as the point where
+ * we switch between random and deterministic routing.
+ */
+static double log_of_network_size_estimate;
 
-#include "gnunet-service-dht_clients.c"
+
+/**
+ * Callback that is called when network size estimate is updated.
+ *
+ * @param cls a `struct Underlay`
+ * @param timestamp time when the estimate was received from the server (or created by the server)
+ * @param logestimate the log(Base 2) value of the current network size estimate
+ * @param std_dev standard deviation for the estimate
+ *
+ */
+static void
+update_network_size_estimate (void *cls,
+                              struct GNUNET_TIME_Absolute timestamp,
+                              double logestimate,
+                              double std_dev)
+{
+  struct Underlay *u = cls;
+  double sum = 0.0;
+
+  GNUNET_STATISTICS_update (GDS_stats,
+                            "# Network size estimates received",
+                            1,
+                            GNUNET_NO);
+  /* do not allow estimates < 0.5 */
+  u->network_size_estimate = pow (2.0,
+                                  GNUNET_MAX (0.5,
+                                              logestimate));
+  for (struct Underlay *p; NULL != p; p = p->next)
+    sum += p->network_size_estimate;
+  if (sum <= 2.0)
+    log_of_network_size_estimate = 0.5;
+  else
+    log_of_network_size_estimate = log2 (sum);
+}
 
 
 /**
- * Receive the HELLO from transport service, free current and replace
- * if necessary.
+ * Return the current NSE
  *
- * @param cls NULL
- * @param message HELLO message of peer
+ * @return the current NSE as a logarithm
+ */
+double
+GDS_NSE_get (void)
+{
+  return log_of_network_size_estimate;
+}
+
+
+#include "gnunet-service-dht_clients.c"
+
+
+/**
+ * Update our HELLO with all of our our addresses.
  */
 static void
-process_hello (void *cls,
-               const struct GNUNET_MessageHeader *message)
+update_hello (void)
 {
   GNUNET_free (GDS_my_hello);
-  GDS_my_hello = GNUNET_malloc (ntohs (message->size));
-  GNUNET_memcpy (GDS_my_hello,
-                 message,
-                 ntohs (message->size));
+  // FIXME: build new HELLO properly!
+}
+
+
+/**
+ * Function to call with new addresses of this peer.
+ *
+ * @param cls the closure
+ * @param address address under which we are likely reachable,
+ *           pointer will remain valid until @e address_del_cb is called; to be used for HELLOs. Example: "ip+udp://$PID/1.1.1.1:2086/"
+ * @param source handle for sending from this address, NULL if we can only receive
+ * @param[out] ctx storage space for DHT to use in association with this address
+ */
+static void
+u_address_add (void *cls,
+               const char *address,
+               struct GNUNET_DHTU_Source *source,
+               void **ctx)
+{
+  struct Underlay *u = cls;
+  struct MyAddress *a;
+
+  a = GNUNET_new (struct MyAddress);
+  a->source = source;
+  a->url = GNUNET_strdup (address);
+  a->u = u;
+  GNUNET_CONTAINER_DLL_insert (a_head,
+                               a_tail,
+                               a);
+  *ctx = a;
+  update_hello ();
+}
+
+
+/**
+ * Function to call with expired addresses of this peer.
+ *
+ * @param[in] ctx storage space used by the DHT in association with this address
+ */
+static void
+u_address_del (void *ctx)
+{
+  struct MyAddress *a = ctx;
+
+  GNUNET_CONTAINER_DLL_remove (a_head,
+                               a_tail,
+                               a);
+  GNUNET_free (a->url);
+  GNUNET_free (a);
+  update_hello ();
 }
 
 
@@ -85,16 +262,10 @@ process_hello (void *cls,
 static void
 shutdown_task (void *cls)
 {
-  if (NULL != ghh)
-  {
-    GNUNET_TRANSPORT_hello_get_cancel (ghh);
-    ghh = NULL;
-  }
   GDS_NEIGHBOURS_done ();
   GDS_DATACACHE_done ();
   GDS_ROUTING_done ();
   GDS_HELLO_done ();
-  GDS_NSE_done ();
   if (NULL != GDS_block_context)
   {
     GNUNET_BLOCK_context_destroy (GDS_block_context);
@@ -113,6 +284,57 @@ shutdown_task (void *cls)
 
 
 /**
+ * Function iterating over all configuration sections.
+ * Loads plugins for enabled DHT underlays.
+ *
+ * @param cls NULL
+ * @param section configuration section to inspect
+ */
+static void
+load_underlay (void *cls,
+               const char *section)
+{
+  struct Underlay *u;
+  char *libname;
+
+  (void) cls;
+  if (0 != strncasecmp (section,
+                        "dhtu-",
+                        strlen ("dhtu-")))
+    return;
+  if (GNUNET_YES !=
+      GNUNET_CONFIGURATION_get_value_yesno (GDS_cfg,
+                                            section,
+                                            "ENABLED"))
+    return;
+  section += strlen ("dhtu-");
+  u = GNUNET_new (struct Underlay);
+  u->env.cls = u;
+  u->env.address_add_cb = &u_address_add;
+  u->env.address_del_cb = &u_address_del;
+  u->env.network_size_cb = &update_network_size_estimate;
+  u->env.connect_cb = &GDS_u_connect;
+  u->env.disconnect_cb = &GDS_u_disconnect;
+  u->env.receive_cb = &GDS_u_receive;
+  GNUNET_asprintf (&libname,
+                   "libgnunet_plugin_dhtu_%s",
+                   section);
+  u->dhtu = GNUNET_PLUGIN_load (libname,
+                                &u->env);
+  if (NULL == u->dhtu)
+  {
+    GNUNET_free (libname);
+    GNUNET_free (u);
+    return;
+  }
+  u->name = GNUNET_strdup (section);
+  GNUNET_CONTAINER_DLL_insert (u_head,
+                               u_tail,
+                               u);
+}
+
+
+/**
  * Process dht requests.
  *
  * @param cls closure
@@ -137,23 +359,21 @@ run (void *cls,
   GDS_block_context = GNUNET_BLOCK_context_create (GDS_cfg);
   GDS_stats = GNUNET_STATISTICS_create ("dht",
                                         GDS_cfg);
-  GNUNET_SERVICE_suspend (GDS_service);
   GDS_CLIENTS_init ();
   GDS_ROUTING_init ();
-  GDS_NSE_init ();
   GDS_DATACACHE_init ();
-  GDS_HELLO_init ();
-  if (GNUNET_OK != GDS_NEIGHBOURS_init ())
+  GNUNET_SCHEDULER_add_shutdown (&shutdown_task,
+                                 NULL);
+  GNUNET_CONFIGURATION_iterate_sections (GDS_cfg,
+                                         &load_underlay,
+                                         NULL);
+  if (NULL == u_head)
   {
-    shutdown_task (NULL);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "No DHT underlays configured!\n");
+    GNUNET_SCHEDULER_shutdown ();
     return;
   }
-  GNUNET_SCHEDULER_add_shutdown (&shutdown_task,
-                                 NULL);
-  ghh = GNUNET_TRANSPORT_hello_get (GDS_cfg,
-                                    GNUNET_TRANSPORT_AC_GLOBAL,
-                                    &process_hello,
-                                    NULL);
 }