-hopefully fixing #2869

1 files changed, 469 insertions, 368 deletions

diff --git a/src/transport/plugin_transport_unix.c b/src/transport/plugin_transport_unix.c
index 646695f79..81aa9cb94 100644
--- a/src/transport/plugin_transport_unix.c
+++ b/src/transport/plugin_transport_unix.c
@@ -1,6 +1,6 @@
 /*
      This file is part of GNUnet
-     (C) 2010 Christian Grothoff (and other contributing authors)
+     (C) 2010, 2013 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
@@ -26,29 +26,22 @@
  * @author Christian Grothoff
  * @author Nathan Evans
  */
-
 #include "platform.h"
 #include "gnunet_hello_lib.h"
-#include "gnunet_connection_lib.h"
-#include "gnunet_container_lib.h"
-#include "gnunet_os_lib.h"
-#include "gnunet_peerinfo_service.h"
+#include "gnunet_util_lib.h"
 #include "gnunet_protocols.h"
-#include "gnunet_resolver_service.h"
-#include "gnunet_server_lib.h"
-#include "gnunet_signatures.h"
 #include "gnunet_statistics_service.h"
 #include "gnunet_transport_service.h"
 #include "gnunet_transport_plugin.h"
 #include "transport.h"
 
-#define MAX_PROBES 20
-#define MAX_RETRIES 3
-#define RETRY 0
-
-#define LOG(kind,...) GNUNET_log_from (kind, "transport-unix",__VA_ARGS__)
 
-#define DEFAULT_NAT_PORT 0
+/**
+ * Return code we give on 'send' if we failed to send right now
+ * but it makes sense to retry later. (Note: we might want to
+ * move this to the plugin API!?).
+ */
+#define RETRY 0
 
 /**
  * How long until we give up on transmitting the welcome message?
@@ -56,10 +49,15 @@
 #define HOSTNAME_RESOLVE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
 
 /**
- * Starting port for listening and sending, eventually a config value
+ * Default "port" to use, if configuration does not specify.
+ * Essentially just a number appended to the UNIX path.
  */
 #define UNIX_NAT_DEFAULT_PORT 22086
 
+
+#define LOG(kind,...) GNUNET_log_from (kind, "transport-unix",__VA_ARGS__)
+
+
 GNUNET_NETWORK_STRUCT_BEGIN
 
 /**
@@ -79,44 +77,89 @@ struct UNIXMessage
 
 };
 
+
+/**
+ * Handle for a session.
+ */
 struct Session
 {
   struct GNUNET_PeerIdentity target;
 
+  struct Plugin * plugin;
+
   void *addr;
+
   size_t addrlen;
 
   /**
    * Session timeout task
    */
   GNUNET_SCHEDULER_TaskIdentifier timeout_task;
-
-  struct Plugin * plugin;
 };
 
+
 struct UNIXMessageWrapper
 {
+  /**
+   * We keep messages in a doubly linked list.
+   */
   struct UNIXMessageWrapper *next;
+
+  /**
+   * We keep messages in a doubly linked list.
+   */
   struct UNIXMessageWrapper *prev;
 
+  /**
+   * The actual payload (allocated separately right now).
+   */
   struct UNIXMessage * msg;
-  size_t msgsize;
-  size_t payload;
-
-  struct GNUNET_TIME_Absolute timeout;
-  unsigned int priority;
 
+  /**
+   * Session this message belongs to.
+   */
   struct Session *session;
+
+  /**
+   * Function to call upon transmission.
+   */
   GNUNET_TRANSPORT_TransmitContinuation cont;
+
+  /**
+   * Closure for 'cont'.
+   */
   void *cont_cls;
+
+  /**
+   * Timeout for this message.
+   */
+  struct GNUNET_TIME_Absolute timeout;
+
+  /**
+   * Number of bytes in 'msg'.
+   */
+  size_t msgsize;
+
+  /**
+   * Number of bytes of payload encapsulated in 'msg'.
+   */
+  size_t payload;
+
+  /**
+   * Priority of the message (ignored, just dragged along in UNIX).
+   */
+  unsigned int priority;
 };
 
-/* Forward definition */
+
+/**
+ * Encapsulation of all of the state of the plugin.
+ */
 struct Plugin;
 
 
 /**
- * UNIX NAT "Session"
+ * UNIX "Session"
  */
 struct PeerSession
 {
@@ -166,6 +209,7 @@ struct PeerSession
 
 };
 
+
 /**
  * Information we keep for each of our listen sockets.
  */
@@ -177,7 +221,9 @@ struct UNIX_Sock_Info
   struct GNUNET_NETWORK_Handle *desc;
 
   /**
-   * The port we bound to
+   * The port we bound to (not an actual PORT, as UNIX domain sockets
+   * don't have ports, but rather a number in the path name to make this
+   * one unique).
    */
   uint16_t port;
 };
@@ -188,30 +234,31 @@ struct UNIX_Sock_Info
  */
 struct Plugin
 {
+
   /**
-   * Our environment.
+   * ID of task used to update our addresses when one expires.
    */
-  struct GNUNET_TRANSPORT_PluginEnvironment *env;
+  GNUNET_SCHEDULER_TaskIdentifier address_update_task;
 
   /**
-   * Sessions
+   * ID of select task
    */
-  struct GNUNET_CONTAINER_MultiHashMap *session_map;
+  GNUNET_SCHEDULER_TaskIdentifier select_task;
 
   /**
-   * ID of task used to update our addresses when one expires.
+   * Number of bytes we currently have in our write queue.
    */
-  GNUNET_SCHEDULER_TaskIdentifier address_update_task;
+  unsigned long long bytes_in_queue;
 
   /**
-   * ID of select task
+   * Our environment.
    */
-  GNUNET_SCHEDULER_TaskIdentifier select_task;
+  struct GNUNET_TRANSPORT_PluginEnvironment *env;
 
   /**
-   * Integer to append to unix domain socket.
+   * Sessions
    */
-  uint16_t port;
+  struct GNUNET_CONTAINER_MultiHashMap *session_map;
 
   /**
    * FD Read set
@@ -223,65 +270,81 @@ struct Plugin
    */
   struct GNUNET_NETWORK_FDSet *ws;
 
-  int with_ws;
-
-  /**
-   * socket that we transmit all data with
-   */
-  struct UNIX_Sock_Info unix_sock;
-
   /**
    * Path of our unix domain socket (/tmp/unix-plugin-PORT)
    */
   char *unix_socket_path;
 
+  /**
+   * Head of queue of messages to transmit.
+   */
   struct UNIXMessageWrapper *msg_head;
+
+  /**
+   * Tail of queue of messages to transmit.
+   */
   struct UNIXMessageWrapper *msg_tail;
 
   /**
+   * socket that we transmit all data with
+   */
+  struct UNIX_Sock_Info unix_sock;
+
+  /**
    * ATS network
    */
   struct GNUNET_ATS_Information ats_network;
 
-  unsigned int bytes_in_queue;
-  unsigned int bytes_in_sent;
-  unsigned int bytes_in_recv;
-  unsigned int bytes_discarded;
+  /**
+   * Is the write set in the current 'select' task?  GNUNET_NO if the
+   * write queue was empty when the main task was scheduled,
+   * GNUNET_YES if we're already waiting for being allowed to write.
+   */
+  int with_ws;
+
+  /**
+   * Integer to append to unix domain socket.
+   */
+  uint16_t port;
+
 };
 
-/**
- * Start session timeout
- */
-static void
-start_session_timeout (struct Session *s);
 
 /**
  * Increment session timeout due to activity
+ *
+ * @param s session for which the timeout should be moved
  */
 static void
 reschedule_session_timeout (struct Session *s);
 
+
 /**
- * Cancel timeout
+ * We have been notified that our writeset has something to read.  We don't
+ * know which socket needs to be read, so we have to check each one
+ * Then reschedule this function to be called again once more is available.
+ *
+ * @param cls the plugin handle
+ * @param tc the scheduling context (for rescheduling this function again)
  */
 static void
-stop_session_timeout (struct Session *s);
-
-
-static void
 unix_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
 
 
+/**
+ * Re-schedule the main 'select' callback (unix_plugin_select)
+ * for this plugin.
+ *
+ * @param plugin the plugin context
+ */
 static void
 reschedule_select (struct Plugin * plugin)
 {
-
   if (plugin->select_task != GNUNET_SCHEDULER_NO_TASK)
   {
     GNUNET_SCHEDULER_cancel (plugin->select_task);
     plugin->select_task = GNUNET_SCHEDULER_NO_TASK;
   }
-
   if (NULL != plugin->msg_head)
   {
     plugin->select_task =
@@ -304,15 +367,36 @@ reschedule_select (struct Plugin * plugin)
   }
 }
 
+
+/**
+ * Closure to 'lookup_session_it'.
+ */
 struct LookupCtx
 {
+  /**
+   * Location to store the session, if found.
+   */
   struct Session *s;
+
+  /**
+   * Address we are looking for.
+   */
   const struct sockaddr_un *addr;
 };
 
-int lookup_session_it (void *cls,
-                       const struct GNUNET_HashCode * key,
-                       void *value)
+
+/**
+ * Function called to find a session by address.
+ *
+ * @param cls the 'struct LookupCtx'
+ * @param key peer we are looking for (unused)
+ * @param value a session
+ * @return GNUNET_YES if not found (continue looking), GNUNET_NO on success
+ */
+static int 
+lookup_session_it (void *cls,
+                   const struct GNUNET_HashCode * key,
+                   void *value)
 {
   struct LookupCtx *lctx = cls;
   struct Session *t = value;
@@ -326,23 +410,33 @@ int lookup_session_it (void *cls,
 }
 
 
+/**
+ * Find an existing session by address.
+ *
+ * @param plugin the plugin
+ * @param sender for which peer should the session be?
+ * @param addr address to look for
+ * @return NULL if session was not found
+ */
 static struct Session *
-lookup_session (struct Plugin *plugin, struct GNUNET_PeerIdentity *sender, const struct sockaddr_un *addr)
+lookup_session (struct Plugin *plugin, 
+                const struct GNUNET_PeerIdentity *sender, 
+                const struct sockaddr_un *addr)
 {
   struct LookupCtx lctx;
 
   GNUNET_assert (NULL != plugin);
   GNUNET_assert (NULL != sender);
   GNUNET_assert (NULL != addr);
-
   lctx.s = NULL;
   lctx.addr = addr;
-
-  GNUNET_CONTAINER_multihashmap_get_multiple (plugin->session_map, &sender->hashPubKey, &lookup_session_it, &lctx);
-
+  GNUNET_CONTAINER_multihashmap_get_multiple (plugin->session_map, 
+                                              &sender->hashPubKey,
+                                              &lookup_session_it, &lctx);
   return lctx.s;
 }
 
+
 /**
  * Functions with this signature are called whenever we need
  * to close a session due to a disconnect or failure to
@@ -353,18 +447,16 @@ lookup_session (struct Plugin *plugin, struct GNUNET_PeerIdentity *sender, const
 static void
 disconnect_session (struct Session *s)
 {
+  struct Plugin *plugin = s->plugin;
   struct UNIXMessageWrapper *msgw;
   struct UNIXMessageWrapper *next;
-  struct Plugin * plugin = s->plugin;
   int removed;
-  GNUNET_assert (plugin != NULL);
-  GNUNET_assert (s != NULL);
 
-  LOG (GNUNET_ERROR_TYPE_DEBUG, "Disconnecting session for peer `%s' `%s' \n", GNUNET_i2s (&s->target), s->addr);
-  stop_session_timeout (s);
+  LOG (GNUNET_ERROR_TYPE_DEBUG, 
+       "Disconnecting session for peer `%s' `%s'\n",
+       GNUNET_i2s (&s->target), 
+       s->addr);
   plugin->env->session_end (plugin->env->cls, &s->target, s);
-
-  msgw = plugin->msg_head;
   removed = GNUNET_NO;
   next = plugin->msg_head;
   while (NULL != next)
@@ -381,85 +473,22 @@ disconnect_session (struct Session *s)
     GNUNET_free (msgw);
     removed = GNUNET_YES;    
   }
+  GNUNET_assert (GNUNET_YES ==
+                 GNUNET_CONTAINER_multihashmap_remove (plugin->session_map, 
+                                                       &s->target.hashPubKey, 
+                                                       s));
+  GNUNET_STATISTICS_set (plugin->env->stats,
+                         "# UNIX sessions active",
+                         GNUNET_CONTAINER_multihashmap_size (plugin->session_map),
+                         GNUNET_NO);
   if ((GNUNET_YES == removed) && (NULL == plugin->msg_head))
     reschedule_select (plugin);
-
-  GNUNET_assert (GNUNET_YES ==
-                 GNUNET_CONTAINER_multihashmap_remove(plugin->session_map, &s->target.hashPubKey, s));
-
-  GNUNET_STATISTICS_set(plugin->env->stats,
-                        "# UNIX sessions active",
-                        GNUNET_CONTAINER_multihashmap_size(plugin->session_map),
-                        GNUNET_NO);
-
-  GNUNET_free (s);
-}
-
-static int
-get_session_delete_it (void *cls, const struct GNUNET_HashCode * key, void *value)
-{
-  struct Session *s = value;
-  disconnect_session (s);
-  return GNUNET_YES;
-}
-
-
-/**
- * Disconnect from a remote node.  Clean up session if we have one for this peer
- *
- * @param cls closure for this call (should be handle to Plugin)
- * @param target the peeridentity of the peer to disconnect
- * @return GNUNET_OK on success, GNUNET_SYSERR if the operation failed
- */
-static void
-unix_disconnect (void *cls, const struct GNUNET_PeerIdentity *target)
-{
-  struct Plugin *plugin = cls;
-  GNUNET_assert (plugin != NULL);
-
-  GNUNET_CONTAINER_multihashmap_get_multiple (plugin->session_map, &target->hashPubKey, &get_session_delete_it, plugin);
-  return;
-}
-
-/**
- * Shutdown the server process (stop receiving inbound traffic). Maybe
- * restarted later!
- *
- * @param cls Handle to the plugin for this transport
- *
- * @return returns the number of sockets successfully closed,
- *         should equal the number of sockets successfully opened
- */
-static int
-unix_transport_server_stop (void *cls)
-{
-  struct Plugin *plugin = cls;
-  struct UNIXMessageWrapper * msgw;
-
-  while (NULL != (msgw = plugin->msg_head))
-  {
-    GNUNET_CONTAINER_DLL_remove (plugin->msg_head, plugin->msg_tail, msgw);
-    if (msgw->cont != NULL)
-      msgw->cont (msgw->cont_cls,  &msgw->session->target, GNUNET_SYSERR,
-                  msgw->payload, 0);
-    GNUNET_free (msgw->msg);
-    GNUNET_free (msgw);
-  }
-
-  if (plugin->select_task != GNUNET_SCHEDULER_NO_TASK)
-  {
-    GNUNET_SCHEDULER_cancel (plugin->select_task);
-    plugin->select_task = GNUNET_SCHEDULER_NO_TASK;
-  }
-
-  if (NULL != plugin->unix_sock.desc)
+  if (GNUNET_SCHEDULER_NO_TASK != s->timeout_task)
   {
-    GNUNET_break (GNUNET_OK ==
-                  GNUNET_NETWORK_socket_close (plugin->unix_sock.desc));
-    plugin->unix_sock.desc = NULL;
-    plugin->with_ws = GNUNET_NO;
+    GNUNET_SCHEDULER_cancel (s->timeout_task);
+    s->timeout_task = GNUNET_SCHEDULER_NO_TASK;
   }
-  return GNUNET_OK;
+  GNUNET_free (s);
 }
 
 
@@ -482,8 +511,7 @@ unix_transport_server_stop (void *cls)
  *        for the next transmission call; or if the
  *        peer disconnected...)
  * @param cont_cls closure for cont
- *
- * @return on success : the number of bytes written, 0 n retry, -1 on errors
+ * @return on success the number of bytes written, RETRY for retry, -1 on errors
  */
 static ssize_t
 unix_real_send (void *cls,
@@ -505,13 +533,12 @@ unix_real_send (void *cls,
   size_t slen;
 
   GNUNET_assert (NULL != plugin);
-
-  if (send_handle == NULL)
+  if (NULL == send_handle)
   {
     GNUNET_break (0); /* We do not have a send handle */
     return GNUNET_SYSERR;
   }
-  if ((addr == NULL) || (addrlen == 0))
+  if ((NULL == addr) || (0 == addrlen))
   {
     GNUNET_break (0); /* Can never send if we don't have an address */
     return GNUNET_SYSERR;
@@ -543,15 +570,10 @@ resend:
 
   if (GNUNET_SYSERR == sent)
   {
-    if (errno == EAGAIN)
-    {
-      return RETRY; /* We have to retry later  */
-    }
-    if (errno == ENOBUFS)
-    {
+    if ( (EAGAIN == errno) ||
+         (ENOBUFS == errno) )
       return RETRY; /* We have to retry later  */
-    }
-    if (errno == EMSGSIZE)
+    if (EMSGSIZE == errno)
     {
       socklen_t size = 0;
       socklen_t len = sizeof (size);
@@ -587,29 +609,55 @@ resend:
   }
 
   LOG (GNUNET_ERROR_TYPE_DEBUG,
-              "UNIX transmit %u-byte message to %s (%d: %s)\n",
-              (unsigned int) msgbuf_size, GNUNET_a2s (sb, sbs), (int) sent,
-              (sent < 0) ? STRERROR (errno) : "ok");
+       "UNIX transmit %u-byte message to %s (%d: %s)\n",
+       (unsigned int) msgbuf_size, 
+       GNUNET_a2s (sb, sbs), 
+       (int) sent,
+       (sent < 0) ? STRERROR (errno) : "ok");
   return sent;
 }
 
-struct gsi_ctx
-{
-  char *address;
-  size_t addrlen;
+
+/**
+ * Closure for 'get_session_it'.
+ */
+struct GetSessionIteratorContext
+{ 
+  /**
+   * Location to store the session, if found.
+   */
   struct Session *res;
+
+  /**
+   * Address information.
+   */
+  const char *address;
+
+  /**
+   * Number of bytes in 'address'
+   */
+  size_t addrlen;
 };
 
 
+/**
+ * Function called to find a session by address.
+ *
+ * @param cls the 'struct LookupCtx'
+ * @param key peer we are looking for (unused)
+ * @param value a session
+ * @return GNUNET_YES if not found (continue looking), GNUNET_NO on success
+ */
 static int
-get_session_it (void *cls, const struct GNUNET_HashCode * key, void *value)
+get_session_it (void *cls, 
+                const struct GNUNET_HashCode *key, 
+                void *value)
 {
-  struct gsi_ctx *gsi = cls;
+  struct GetSessionIteratorContext *gsi = cls;
   struct Session *s = value;
 
-  LOG (GNUNET_ERROR_TYPE_DEBUG, "Comparing session %s %s\n", gsi->address, s->addr);
-  if ((gsi->addrlen == s->addrlen) &&
-      (0 == memcmp (gsi->address, s->addr, s->addrlen)))
+  if ( (gsi->addrlen == s->addrlen) &&
+       (0 == memcmp (gsi->address, s->addr, s->addrlen)) )
   {
     gsi->res = s;
     return GNUNET_NO;
@@ -617,6 +665,29 @@ get_session_it (void *cls, const struct GNUNET_HashCode * key, void *value)
   return GNUNET_YES;
 }
 
+
+/**
+ * Session was idle for too long, so disconnect it
+ *
+ * @param cls the 'struct Session' to disconnect
+ * @param tc scheduler context
+ */
+static void
+session_timeout (void *cls, 
+                 const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct Session *s = cls;
+  
+  s->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Session %p was idle for %s, disconnecting\n",
+       s,
+       GNUNET_STRINGS_relative_time_to_string (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
+                                               GNUNET_YES));
+  disconnect_session (s);
+}
+
+
 /**
  * Creates a new outbound session the transport service will use to send data to the
  * peer
@@ -627,60 +698,56 @@ get_session_it (void *cls, const struct GNUNET_HashCode * key, void *value)
  */
 static struct Session *
 unix_plugin_get_session (void *cls,
-                  const struct GNUNET_HELLO_Address *address)
+                         const struct GNUNET_HELLO_Address *address)
 {
-  struct Session * s = NULL;
   struct Plugin *plugin = cls;
-  struct gsi_ctx gsi;
+  struct Session *s;
+  struct GetSessionIteratorContext gsi;
 
-  /* Checks */
-  GNUNET_assert (plugin != NULL);
-  GNUNET_assert (address != NULL);
+  GNUNET_assert (NULL != plugin);
+  GNUNET_assert (NULL != address);
 
   /* Check if already existing */
-  gsi.address = (char *) address->address;
+  gsi.address = (const char *) address->address;
   gsi.addrlen = address->address_length;
   gsi.res = NULL;
-  GNUNET_CONTAINER_multihashmap_get_multiple (plugin->session_map, &address->peer.hashPubKey, &get_session_it, &gsi);
-  if (gsi.res != NULL)
+  GNUNET_CONTAINER_multihashmap_get_multiple (plugin->session_map, 
+                                              &address->peer.hashPubKey, 
+                                              &get_session_it, &gsi);
+  if (NULL != gsi.res)
   {
-    LOG (GNUNET_ERROR_TYPE_DEBUG, "Found existing session\n");
+    LOG (GNUNET_ERROR_TYPE_DEBUG, 
+         "Found existing session\n");
     return gsi.res;
   }
 
-  /* Create a new session */
+  /* create a new session */
   s = GNUNET_malloc (sizeof (struct Session) + address->address_length);
   s->addr = &s[1];
   s->addrlen = address->address_length;
   s->plugin = plugin;
-  memcpy(s->addr, address->address, s->addrlen);
-  memcpy(&s->target, &address->peer, sizeof (struct GNUNET_PeerIdentity));
+  memcpy (s->addr, address->address, s->addrlen);
+  memcpy (&s->target, &address->peer, sizeof (struct GNUNET_PeerIdentity));
 
-  start_session_timeout (s);
-
-  GNUNET_CONTAINER_multihashmap_put (plugin->session_map,
-      &address->peer.hashPubKey, s,
-      GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
-
-  GNUNET_STATISTICS_set(plugin->env->stats,
-                        "# UNIX sessions active",
-                        GNUNET_CONTAINER_multihashmap_size(plugin->session_map),
-                        GNUNET_NO);
-  LOG (GNUNET_ERROR_TYPE_DEBUG, "Creating new session\n");
+  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == s->timeout_task);
+  s->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
+                                                  &session_timeout,
+                                                  s);
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Creating a new session %p with timeout set to %s\n",
+       s,  
+       GNUNET_STRINGS_relative_time_to_string (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
+                                               GNUNET_YES));
+  (void) GNUNET_CONTAINER_multihashmap_put (plugin->session_map,
+                                            &address->peer.hashPubKey, s,
+                                            GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
+  GNUNET_STATISTICS_set (plugin->env->stats,
+                         "# UNIX sessions active",
+                         GNUNET_CONTAINER_multihashmap_size (plugin->session_map),
+                         GNUNET_NO);
   return s;
 }
 
-/*
- * @param cls the plugin handle
- * @param tc the scheduling context (for rescheduling this function again)
- *
- * We have been notified that our writeset has something to read.  We don't
- * know which socket needs to be read, so we have to check each one
- * Then reschedule this function to be called again once more is available.
- *
- */
-static void
-unix_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
 
 /**
  * Function that can be used by the transport service to transmit
@@ -722,24 +789,26 @@ unix_plugin_send (void *cls,
   struct UNIXMessage *message;
   int ssize;
   
-  GNUNET_assert (plugin != NULL);
-  GNUNET_assert (session != NULL);
+  GNUNET_assert (NULL != plugin);
+  GNUNET_assert (NULL != session);
 
-  if (GNUNET_OK != GNUNET_CONTAINER_multihashmap_contains_value(plugin->session_map,
-      &session->target.hashPubKey, session))
+  if (GNUNET_OK != 
+      GNUNET_CONTAINER_multihashmap_contains_value (plugin->session_map,
+                                                    &session->target.hashPubKey,
+                                                    session))
   {
-    LOG (GNUNET_ERROR_TYPE_ERROR, "Invalid session for peer `%s' `%s'\n",
-                GNUNET_i2s (&session->target),
-                (char *) session->addr);
+    LOG (GNUNET_ERROR_TYPE_ERROR, 
+         "Invalid session for peer `%s' `%s'\n",
+         GNUNET_i2s (&session->target),
+         (const char *) session->addr);
     GNUNET_break (0);
-
     return GNUNET_SYSERR;
   }
-  LOG (GNUNET_ERROR_TYPE_DEBUG, "Sending %u bytes with session for peer `%s' `%s'\n",
-                msgbuf_size,
-        GNUNET_i2s (&session->target),
-        (char *) session->addr);
-
+  LOG (GNUNET_ERROR_TYPE_DEBUG, 
+       "Sending %u bytes with session for peer `%s' `%s'\n",
+       msgbuf_size,
+       GNUNET_i2s (&session->target),
+       (const char *) session->addr);
   ssize = sizeof (struct UNIXMessage) + msgbuf_size;
   message = GNUNET_malloc (sizeof (struct UNIXMessage) + msgbuf_size);
   message->header.size = htons (ssize);
@@ -747,9 +816,7 @@ unix_plugin_send (void *cls,
   memcpy (&message->sender, plugin->env->my_identity,
           sizeof (struct GNUNET_PeerIdentity));
   memcpy (&message[1], msgbuf, msgbuf_size);
-
   reschedule_session_timeout (session);
-
   wrapper = GNUNET_malloc (sizeof (struct UNIXMessageWrapper));
   wrapper->msg = message;
   wrapper->msgsize = ssize;
@@ -759,20 +826,16 @@ unix_plugin_send (void *cls,
   wrapper->cont = cont;
   wrapper->cont_cls = cont_cls;
   wrapper->session = session;
-
-  GNUNET_CONTAINER_DLL_insert(plugin->msg_head, plugin->msg_tail, wrapper);
-
+  GNUNET_CONTAINER_DLL_insert (plugin->msg_head, 
+                               plugin->msg_tail,
+                               wrapper);
   plugin->bytes_in_queue += ssize;
-  GNUNET_STATISTICS_set (plugin->env->stats,"# bytes currently in UNIX buffers",
-      plugin->bytes_in_queue, GNUNET_NO);
-
-  LOG (GNUNET_ERROR_TYPE_DEBUG, "Sent %d bytes to `%s'\n", ssize,
-              (char *) session->addr);
-  if (plugin->with_ws == GNUNET_NO)
-  {
+  GNUNET_STATISTICS_set (plugin->env->stats,
+                         "# bytes currently in UNIX buffers",
+                         plugin->bytes_in_queue, 
+                         GNUNET_NO);
+  if (GNUNET_NO == plugin->with_ws)
     reschedule_select (plugin);
-  }
-
   return ssize;
 }
 
@@ -798,16 +861,18 @@ unix_demultiplexer (struct Plugin *plugin, struct GNUNET_PeerIdentity *sender,
 
   GNUNET_assert (fromlen >= sizeof (struct sockaddr_un));
 
-  LOG (GNUNET_ERROR_TYPE_DEBUG, "Received message from %s\n",
-              un->sun_path);
-
-
-
-  plugin->bytes_in_recv += ntohs(currhdr->size);
-  GNUNET_STATISTICS_set (plugin->env->stats,"# bytes received via UNIX",
-      plugin->bytes_in_recv, GNUNET_NO);
-
-  addr = GNUNET_HELLO_address_allocate(sender, "unix", un->sun_path, strlen (un->sun_path) + 1);
+  LOG (GNUNET_ERROR_TYPE_DEBUG, 
+       "Received message from %s\n",
+       un->sun_path);
+  GNUNET_STATISTICS_update (plugin->env->stats,
+                            "# bytes received via UNIX",
+                            ntohs (currhdr->size),
+                            GNUNET_NO);
+
+  addr = GNUNET_HELLO_address_allocate (sender,
+                                        "unix",
+                                        un->sun_path, 
+                                        strlen (un->sun_path) + 1);
   s = lookup_session (plugin, sender, un);
   if (NULL == s)
     s = unix_plugin_get_session (plugin, addr);
@@ -827,8 +892,13 @@ unix_demultiplexer (struct Plugin *plugin, struct GNUNET_PeerIdentity *sender,
 }
 
 
+/**
+ * Read from UNIX domain socket (it is ready).
+ *
+ * @param plugin the plugin
+ */
 static void
-unix_plugin_select_read (struct Plugin * plugin)
+unix_plugin_select_read (struct Plugin *plugin)
 {
   char buf[65536] GNUNET_ALIGN;
   struct UNIXMessage *msg;
@@ -889,44 +959,48 @@ unix_plugin_select_read (struct Plugin * plugin)
       GNUNET_break_op (0);
       break;
     }
-
     unix_demultiplexer (plugin, &sender, currhdr, &un, sizeof (un));
     offset += csize;
   }
 }
 
 
+/**
+ * Write to UNIX domain socket (it is ready).
+ *
+ * @param plugin the plugin
+ */
 static void
-unix_plugin_select_write (struct Plugin * plugin)
+unix_plugin_select_write (struct Plugin *plugin)
 {
   int sent = 0;
+  struct UNIXMessageWrapper * msgw;
 
-  struct UNIXMessageWrapper * msgw = plugin->msg_tail;
-  while (NULL != msgw)
+  while (NULL != (msgw = plugin->msg_tail))
   {
-      if (GNUNET_TIME_absolute_get_remaining (msgw->timeout).rel_value > 0)
-        break; /* Message is ready for sending */
-      else
-      {
-          /* Message has a timeout */
-            LOG (GNUNET_ERROR_TYPE_DEBUG,
-              "Timeout for message with %llu bytes \n", msgw->msgsize);
-          GNUNET_CONTAINER_DLL_remove (plugin->msg_head, plugin->msg_tail, msgw);
-          if (NULL != msgw->cont)
-            msgw->cont (msgw->cont_cls, &msgw->session->target, GNUNET_SYSERR, msgw->payload, 0);
-
-          plugin->bytes_in_queue -= msgw->msgsize;
-          GNUNET_STATISTICS_set (plugin->env->stats, "# bytes currently in UNIX buffers",
-              plugin->bytes_in_queue, GNUNET_NO);
-
-          plugin->bytes_discarded += msgw->msgsize;
-          GNUNET_STATISTICS_set (plugin->env->stats,"# UNIX bytes discarded",
-              plugin->bytes_discarded, GNUNET_NO);
-
-          GNUNET_free (msgw->msg);
-          GNUNET_free (msgw);
-      }
-      msgw = plugin->msg_tail;
+    if (GNUNET_TIME_absolute_get_remaining (msgw->timeout).rel_value > 0)
+      break; /* Message is ready for sending */
+    /* Message has a timeout */
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Timeout for message with %u bytes \n", 
+         (unsigned int) msgw->msgsize);
+    GNUNET_CONTAINER_DLL_remove (plugin->msg_head, plugin->msg_tail, msgw);
+    plugin->bytes_in_queue -= msgw->msgsize;
+    GNUNET_STATISTICS_set (plugin->env->stats, 
+                           "# bytes currently in UNIX buffers",
+                           plugin->bytes_in_queue, GNUNET_NO);    
+    GNUNET_STATISTICS_update (plugin->env->stats,
+                              "# UNIX bytes discarded",
+                              msgw->msgsize,
+                              GNUNET_NO);
+    if (NULL != msgw->cont)
+      msgw->cont (msgw->cont_cls,
+                  &msgw->session->target, 
+                  GNUNET_SYSERR, 
+                  msgw->payload, 
+                  0);    
+    GNUNET_free (msgw->msg);
+    GNUNET_free (msgw);  
   }
   if (NULL == msgw)
     return; /* Nothing to send at the moment */
@@ -945,11 +1019,12 @@ unix_plugin_select_write (struct Plugin * plugin)
 
   if (RETRY == sent)
   {
-    GNUNET_STATISTICS_update (plugin->env->stats,"# UNIX retry attempts",
-          1, GNUNET_NO);
-
+    GNUNET_STATISTICS_update (plugin->env->stats,
+                              "# UNIX retry attempts",
+                              1, GNUNET_NO);
+    return;
   }
-  else if (GNUNET_SYSERR == sent)
+  if (GNUNET_SYSERR == sent)
   {
     /* failed and no retry */
     if (NULL != msgw->cont)
@@ -959,36 +1034,40 @@ unix_plugin_select_write (struct Plugin * plugin)
 
     GNUNET_assert (plugin->bytes_in_queue >= msgw->msgsize);
     plugin->bytes_in_queue -= msgw->msgsize;
-    GNUNET_STATISTICS_set (plugin->env->stats, "# bytes currently in UNIX buffers",
-        plugin->bytes_in_queue, GNUNET_NO);
-    plugin->bytes_discarded += msgw->msgsize;
-    GNUNET_STATISTICS_set (plugin->env->stats,"# UNIX bytes discarded",
-        plugin->bytes_discarded, GNUNET_NO);
-
-    GNUNET_free (msgw->msg);
-    GNUNET_free (msgw);
-    return;
-  }
-  else if (sent > 0)
-  {
-    /* successfully sent bytes */
-    if (NULL != msgw->cont)
-      msgw->cont (msgw->cont_cls, &msgw->session->target, GNUNET_OK, msgw->payload, msgw->msgsize);
-
-    GNUNET_CONTAINER_DLL_remove(plugin->msg_head, plugin->msg_tail, msgw);
-
-    GNUNET_assert (plugin->bytes_in_queue >= msgw->msgsize);
-    plugin->bytes_in_queue -= msgw->msgsize;
-    GNUNET_STATISTICS_set (plugin->env->stats,"# bytes currently in UNIX buffers",
-        plugin->bytes_in_queue, GNUNET_NO);
-    plugin->bytes_in_sent += msgw->msgsize;
-    GNUNET_STATISTICS_set (plugin->env->stats,"# bytes transmitted via UNIX",
-        plugin->bytes_in_sent, GNUNET_NO);
+    GNUNET_STATISTICS_set (plugin->env->stats, 
+                           "# bytes currently in UNIX buffers",
+                           plugin->bytes_in_queue, GNUNET_NO);
+    GNUNET_STATISTICS_update (plugin->env->stats,
+                              "# UNIX bytes discarded",
+                              msgw->msgsize,
+                              GNUNET_NO);
 
     GNUNET_free (msgw->msg);
     GNUNET_free (msgw);
     return;
   }
+  /* successfully sent bytes */
+  GNUNET_break (sent > 0);
+  GNUNET_CONTAINER_DLL_remove (plugin->msg_head, 
+                               plugin->msg_tail, 
+                               msgw); 
+  GNUNET_assert (plugin->bytes_in_queue >= msgw->msgsize);
+  plugin->bytes_in_queue -= msgw->msgsize;
+  GNUNET_STATISTICS_set (plugin->env->stats,
+                         "# bytes currently in UNIX buffers",
+                         plugin->bytes_in_queue,
+                         GNUNET_NO);
+  GNUNET_STATISTICS_update (plugin->env->stats,
+                            "# bytes transmitted via UNIX",
+                            msgw->msgsize,
+                            GNUNET_NO);  
+  if (NULL != msgw->cont)
+    msgw->cont (msgw->cont_cls, &msgw->session->target, 
+                GNUNET_OK,
+                msgw->payload, 
+                msgw->msgsize);  
+  GNUNET_free (msgw->msg);
+  GNUNET_free (msgw);
 }
 
 
@@ -1001,7 +1080,8 @@ unix_plugin_select_write (struct Plugin * plugin)
  * @param tc the scheduling context (for rescheduling this function again)
  */
 static void
-unix_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+unix_plugin_select (void *cls,
+                    const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct Plugin *plugin = cls;
 
@@ -1014,7 +1094,7 @@ unix_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     /* Ready to send data */
     GNUNET_assert (GNUNET_NETWORK_fdset_isset
                    (tc->write_ready, plugin->unix_sock.desc));
-    if (plugin->msg_head != NULL)
+    if (NULL != plugin->msg_head)
       unix_plugin_select_write (plugin);
   }
 
@@ -1025,7 +1105,6 @@ unix_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
                    (tc->read_ready, plugin->unix_sock.desc));
     unix_plugin_select_read (plugin);
   }
-
   reschedule_select (plugin);
 }
 
@@ -1221,10 +1300,12 @@ unix_address_to_string (void *cls, const void *addr, size_t addrlen)
  * @param tc unused
  */
 static void
-address_notification (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+address_notification (void *cls,
+                      const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct Plugin *plugin = cls;
 
+  plugin->address_update_task = GNUNET_SCHEDULER_NO_TASK;
   plugin->env->notify_address (plugin->env->cls, GNUNET_YES,
                                plugin->unix_socket_path,
                                strlen (plugin->unix_socket_path) + 1,
@@ -1233,80 +1314,71 @@ address_notification (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 
 
 /**
- * Session was idle, so disconnect it
- */
-static void
-session_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
-{
-  GNUNET_assert (NULL != cls);
-  struct Session *s = cls;
-
-  s->timeout_task = GNUNET_SCHEDULER_NO_TASK;
-  LOG (GNUNET_ERROR_TYPE_DEBUG,
-              "Session %p was idle for %llu ms, disconnecting\n",
-              s, (unsigned long long) GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT.rel_value);
-  /* call session destroy function */
-  disconnect_session(s);
-}
-
-
-/**
- * Start session timeout
+ * Increment session timeout due to activity
+ *
+ * @param s session for which the timeout should be moved
  */
 static void
-start_session_timeout (struct Session *s)
+reschedule_session_timeout (struct Session *s)
 {
   GNUNET_assert (NULL != s);
-  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == s->timeout_task);
+  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != s->timeout_task);
+  GNUNET_SCHEDULER_cancel (s->timeout_task);
   s->timeout_task =  GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
                                                    &session_timeout,
                                                    s);
   LOG (GNUNET_ERROR_TYPE_DEBUG,
-              "Timeout for session %p set to %llu ms\n",
-              s,  (unsigned long long) GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT.rel_value);
+       "Timeout rescheduled for session %p set to %s\n",
+       s,
+       GNUNET_STRINGS_relative_time_to_string (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
+                                               GNUNET_YES));
 }
 
 
 /**
- * Increment session timeout due to activity
+ * Function called on sessions to disconnect
+ *
+ * @param cls the plugin (unused)
+ * @param key peer identity (unused)
+ * @param value the 'struct Session' to disconnect
+ * @return GNUNET_YES (always, continue to iterate)
  */
-static void
-reschedule_session_timeout (struct Session *s)
+static int
+get_session_delete_it (void *cls, const struct GNUNET_HashCode * key, void *value)
 {
-  GNUNET_assert (NULL != s);
-  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != s->timeout_task);
+  struct Session *s = value;
 
-  GNUNET_SCHEDULER_cancel (s->timeout_task);
-  s->timeout_task =  GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
-                                                   &session_timeout,
-                                                   s);
-  LOG (GNUNET_ERROR_TYPE_DEBUG,
-              "Timeout rescheduled for session %p set to %llu ms\n",
-              s, (unsigned long long) GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT.rel_value);
+  disconnect_session (s);
+  return GNUNET_YES;
 }
 
 
 /**
- * Cancel timeout
+ * Disconnect from a remote node.  Clean up session if we have one for this peer
+ *
+ * @param cls closure for this call (should be handle to Plugin)
+ * @param target the peeridentity of the peer to disconnect
+ * @return GNUNET_OK on success, GNUNET_SYSERR if the operation failed
  */
 static void
-stop_session_timeout (struct Session *s)
+unix_disconnect (void *cls, 
+                 const struct GNUNET_PeerIdentity *target)
 {
-  GNUNET_assert (NULL != s);
+  struct Plugin *plugin = cls;
 
-  if (GNUNET_SCHEDULER_NO_TASK != s->timeout_task)
-  {
-    GNUNET_SCHEDULER_cancel (s->timeout_task);
-    s->timeout_task = GNUNET_SCHEDULER_NO_TASK;
-    LOG (GNUNET_ERROR_TYPE_DEBUG,
-                "Timeout stopped for session %p canceled\n",
-                s, (unsigned long long) GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT.rel_value);
-  }
+  GNUNET_assert (plugin != NULL);
+  GNUNET_CONTAINER_multihashmap_get_multiple (plugin->session_map,
+                                              &target->hashPubKey, 
+                                              &get_session_delete_it, plugin);
 }
 
+
 /**
- * The exported method. Makes the core api available via a global and
- * returns the unix transport API.
+ * The exported method.  Initializes the plugin and returns a
+ * struct with the callbacks.
+ *
+ * @param cls the plugin's execution environment
+ * @return NULL on error, plugin functions otherwise
  */
 void *
 libgnunet_plugin_transport_unix_init (void *cls)
@@ -1335,7 +1407,8 @@ libgnunet_plugin_transport_unix_init (void *cls)
   plugin = GNUNET_malloc (sizeof (struct Plugin));
   plugin->port = port;
   plugin->env = env;
-  GNUNET_asprintf (&plugin->unix_socket_path, "/tmp/unix-plugin-sock.%d",
+  GNUNET_asprintf (&plugin->unix_socket_path, 
+                   "/tmp/unix-plugin-sock.%d",
                    plugin->port);
 
   api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
@@ -1349,39 +1422,67 @@ libgnunet_plugin_transport_unix_init (void *cls)
   api->check_address = &unix_check_address;
   api->string_to_address = &unix_string_to_address;
   sockets_created = unix_transport_server_start (plugin);
-  if (sockets_created == 0)
-    LOG (GNUNET_ERROR_TYPE_WARNING, _("Failed to open UNIX sockets\n"));
-
+  if (0 == sockets_created)
+    LOG (GNUNET_ERROR_TYPE_WARNING,
+         _("Failed to open UNIX listen socket\n"));
   plugin->session_map = GNUNET_CONTAINER_multihashmap_create (10, GNUNET_NO);
-
-  GNUNET_SCHEDULER_add_now (address_notification, plugin);
+  plugin->address_update_task = GNUNET_SCHEDULER_add_now (&address_notification, plugin);
   return api;
 }
 
+
+/**
+ * Shutdown the plugin.
+ *
+ * @param cls the plugin API returned from the initialization function
+ * @return NULL (always)
+ */
 void *
 libgnunet_plugin_transport_unix_done (void *cls)
 {
   struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
   struct Plugin *plugin = api->cls;
+  struct UNIXMessageWrapper * msgw;
 
   if (NULL == plugin)
   {
     GNUNET_free (api);
     return NULL;
   }
-
   plugin->env->notify_address (plugin->env->cls, GNUNET_NO,
                                plugin->unix_socket_path,
                                strlen (plugin->unix_socket_path) + 1,
                                "unix");
+  while (NULL != (msgw = plugin->msg_head))
+  {
+    GNUNET_CONTAINER_DLL_remove (plugin->msg_head, plugin->msg_tail, msgw);
+    if (msgw->cont != NULL)
+      msgw->cont (msgw->cont_cls,  &msgw->session->target, GNUNET_SYSERR,
+                  msgw->payload, 0);
+    GNUNET_free (msgw->msg);
+    GNUNET_free (msgw);
+  }
 
-  unix_transport_server_stop (plugin);
-
-
-  GNUNET_CONTAINER_multihashmap_iterate (plugin->session_map, &get_session_delete_it, plugin);
+  if (GNUNET_SCHEDULER_NO_TASK != plugin->select_task)
+  {
+    GNUNET_SCHEDULER_cancel (plugin->select_task);
+    plugin->select_task = GNUNET_SCHEDULER_NO_TASK;
+  }
+  if (GNUNET_SCHEDULER_NO_TASK != plugin->address_update_task)
+  {
+    GNUNET_SCHEDULER_cancel (plugin->address_update_task);
+    plugin->address_update_task = GNUNET_SCHEDULER_NO_TASK;
+  }
+  if (NULL != plugin->unix_sock.desc)
+  {
+    GNUNET_break (GNUNET_OK ==
+                  GNUNET_NETWORK_socket_close (plugin->unix_sock.desc));
+    plugin->unix_sock.desc = NULL;
+    plugin->with_ws = GNUNET_NO;
+  }
+  GNUNET_CONTAINER_multihashmap_iterate (plugin->session_map,
+                                         &get_session_delete_it, plugin);
   GNUNET_CONTAINER_multihashmap_destroy (plugin->session_map);
-
-
   if (NULL != plugin->rs)
     GNUNET_NETWORK_fdset_destroy (plugin->rs);
   if (NULL != plugin->ws)