added helper for handling the "view" in rps
[oweals/gnunet.git] / src / nat / nat_mini.c
index b67718407aebd88a0ece822cc3d84b490d3197ff..45f2e02fe69d48e75ee5d5a320f0eb702ad87232 100644 (file)
@@ -1,6 +1,6 @@
 /*
      This file is part of GNUnet.
-     (C) 2011 Christian Grothoff (and other contributing authors)
+     Copyright (C) 2011-2014 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
 
      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.
+     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+     Boston, MA 02110-1301, USA.
 */
 
 /**
  * @file nat/nat_mini.c
- * @brief functions for interaction with miniupnp
+ * @brief functions for interaction with miniupnp; tested with miniupnpc 1.5
  * @author Christian Grothoff
  */
 #include "platform.h"
 #include "gnunet_nat_lib.h"
 #include "nat.h"
 
+#define LOG(kind,...) GNUNET_log_from (kind, "nat", __VA_ARGS__)
 
 /**
- * Try to get the external IPv4 address of this peer.
- * Note: calling this function may block this process
- * for a few seconds (!).
- *
- * @param addr address to set
- * @return GNUNET_OK on success,
- *         GNUNET_NO if the result is questionable,
- *         GNUNET_SYSERR on error
+ * How long do we give upnpc to create a mapping?
+ */
+#define MAP_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
+
+/**
+ * How long do we give upnpc to remove a mapping?
+ */
+#define UNMAP_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
+
+/**
+ * How often do we check for changes in the mapping?
+ */
+#define MAP_REFRESH_FREQ GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 5)
+
+
+
+/**
+ * Opaque handle to cancel "GNUNET_NAT_mini_get_external_ipv4" operation.
  */
-int
-GNUNET_NAT_mini_get_external_ipv4 (struct in_addr *addr)
+struct GNUNET_NAT_ExternalHandle
 {
+
+  /**
+   * Function to call with the result.
+   */
+  GNUNET_NAT_IPCallback cb;
+
+  /**
+   * Closure for @e cb.
+   */
+  void *cb_cls;
+
+  /**
+   * Read task.
+   */
+  struct GNUNET_SCHEDULER_Task * task;
+
+  /**
+   * Handle to 'external-ip' process.
+   */
   struct GNUNET_OS_Process *eip;
+
+  /**
+   * Handle to stdout pipe of 'external-ip'.
+   */
   struct GNUNET_DISK_PipeHandle *opipe;
+
+  /**
+   * Read handle of @e opipe.
+   */
   const struct GNUNET_DISK_FileHandle *r;
+
+  /**
+   * When should this operation time out?
+   */
+  struct GNUNET_TIME_Absolute timeout;
+
+  /**
+   * Number of bytes in 'buf' that are valid.
+   */
   size_t off;
+
+  /**
+   * Destination of our read operation (output of 'external-ip').
+   */
   char buf[17];
+
+  /**
+   * Error code for better debugging and user feedback
+   */
+  enum GNUNET_NAT_StatusCode ret;
+};
+
+
+/**
+ * Read the output of 'external-ip' into buf.  When complete, parse the
+ * address and call our callback.
+ *
+ * @param cls the `struct GNUNET_NAT_ExternalHandle`
+ * @param tc scheduler context
+ */
+static void
+read_external_ipv4 (void *cls,
+                    const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_NAT_ExternalHandle *eh = cls;
   ssize_t ret;
-  int iret;
-
-  opipe = GNUNET_DISK_pipe (GNUNET_YES,
-                           GNUNET_NO,
-                           GNUNET_YES);
-  eip = GNUNET_OS_start_process (NULL,
-                                opipe,
-                                "external-ip",
-                                "external-ip", NULL);
-  if (NULL == eip)
+  struct in_addr addr;
+
+  eh->task = NULL;
+  if (GNUNET_YES == GNUNET_NETWORK_fdset_handle_isset (tc->read_ready, eh->r))
+    ret =
+        GNUNET_DISK_file_read (eh->r, &eh->buf[eh->off],
+                               sizeof (eh->buf) - eh->off);
+  else {
+    eh->ret = GNUNET_NAT_ERROR_IPC_FAILURE;
+    ret = -1;                   /* error reading, timeout, etc. */
+  }
+  if (ret > 0)
+  {
+    /* try to read more */
+    eh->off += ret;
+    eh->task =
+        GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_absolute_get_remaining
+                                        (eh->timeout), eh->r,
+                                        &read_external_ipv4, eh);
+    return;
+  }
+  eh->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_UTILITY_OUTPUT_INVALID;
+  if ((eh->off > 7) && (eh->buf[eh->off - 1] == '\n'))
+  {
+    eh->buf[eh->off - 1] = '\0';
+    if (1 == inet_pton (AF_INET, eh->buf, &addr))
     {
-      GNUNET_DISK_pipe_close (opipe);
-      return GNUNET_SYSERR;
+      if (0 != addr.s_addr)
+        eh->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_ADDRESS_INVALID;       /* got 0.0.0.0 */
+      else
+        eh->ret = GNUNET_NAT_ERROR_SUCCESS;
     }
-  GNUNET_DISK_pipe_close_end (opipe, GNUNET_DISK_PIPE_END_WRITE);
-  iret = GNUNET_SYSERR;
-  r = GNUNET_DISK_pipe_handle (opipe,
-                              GNUNET_DISK_PIPE_END_READ);
-  off = 0;
-  while (0 < (ret = GNUNET_DISK_file_read (r, &buf[off], sizeof (buf)-off)))
-    off += ret;
-  if ( (off > 7) &&    
-       (buf[off-1] == '\n') )    
+  }
+  eh->cb (eh->cb_cls,
+          (GNUNET_NAT_ERROR_SUCCESS == eh->ret) ? &addr : NULL,
+          eh->ret);
+  GNUNET_NAT_mini_get_external_ipv4_cancel (eh);
+}
+
+
+/**
+ * (Asynchronously) signal error invoking "external-ip" to client.
+ *
+ * @param cls the `struct GNUNET_NAT_ExternalHandle` (freed)
+ * @param tc scheduler context
+ */
+static void
+signal_external_ip_error (void *cls,
+                          const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_NAT_ExternalHandle *eh = cls;
+
+  eh->task = NULL;
+  eh->cb (eh->cb_cls,
+          NULL,
+          eh->ret);
+  GNUNET_free (eh);
+}
+
+
+/**
+ * Try to get the external IPv4 address of this peer.
+ *
+ * @param timeout when to fail
+ * @param cb function to call with result
+ * @param cb_cls closure for @a cb
+ * @return handle for cancellation (can only be used until @a cb is called), never NULL
+ */
+struct GNUNET_NAT_ExternalHandle *
+GNUNET_NAT_mini_get_external_ipv4 (struct GNUNET_TIME_Relative timeout,
+                                   GNUNET_NAT_IPCallback cb, void *cb_cls)
+{
+  struct GNUNET_NAT_ExternalHandle *eh;
+
+  eh = GNUNET_new (struct GNUNET_NAT_ExternalHandle);
+  eh->cb = cb;
+  eh->cb_cls = cb_cls;
+  eh->ret = GNUNET_NAT_ERROR_SUCCESS;
+  if (GNUNET_SYSERR ==
+      GNUNET_OS_check_helper_binary ("external-ip", GNUNET_NO, NULL))
+  {
+    LOG (GNUNET_ERROR_TYPE_INFO,
+        _("`external-ip' command not found\n"));
+    eh->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_UTILITY_NOT_FOUND;
+    eh->task = GNUNET_SCHEDULER_add_now (&signal_external_ip_error,
+                                         eh);
+    return eh;
+  }
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Running `external-ip' to determine our external IP\n");
+  eh->opipe = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_YES, GNUNET_NO, GNUNET_YES);
+  if (NULL == eh->opipe)
+  {
+    eh->ret = GNUNET_NAT_ERROR_IPC_FAILURE;
+    eh->task = GNUNET_SCHEDULER_add_now (&signal_external_ip_error,
+                                         eh);
+    return eh;
+  }
+  eh->eip =
+      GNUNET_OS_start_process (GNUNET_NO, 0, NULL, eh->opipe, NULL,
+                               "external-ip", "external-ip",
+                               NULL);
+  if (NULL == eh->eip)
+  {
+    GNUNET_DISK_pipe_close (eh->opipe);
+    eh->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_UTILITY_FAILED;
+    eh->task = GNUNET_SCHEDULER_add_now (&signal_external_ip_error,
+                                         eh);
+    return eh;
+  }
+  GNUNET_DISK_pipe_close_end (eh->opipe, GNUNET_DISK_PIPE_END_WRITE);
+  eh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
+  eh->r = GNUNET_DISK_pipe_handle (eh->opipe, GNUNET_DISK_PIPE_END_READ);
+  eh->task =
+      GNUNET_SCHEDULER_add_read_file (timeout,
+                                      eh->r,
+                                      &read_external_ipv4, eh);
+  return eh;
+}
+
+
+/**
+ * Cancel operation.
+ *
+ * @param eh operation to cancel
+ */
+void
+GNUNET_NAT_mini_get_external_ipv4_cancel (struct GNUNET_NAT_ExternalHandle *eh)
+{
+  if (NULL != eh->eip)
+  {
+    (void) GNUNET_OS_process_kill (eh->eip, SIGKILL);
+    GNUNET_OS_process_destroy (eh->eip);
+  }
+  if (NULL != eh->opipe)
+    GNUNET_DISK_pipe_close (eh->opipe);
+  if (NULL != eh->task)
+    GNUNET_SCHEDULER_cancel (eh->task);
+  GNUNET_free (eh);
+}
+
+
+/**
+ * Handle to a mapping created with upnpc.
+ */
+struct GNUNET_NAT_MiniHandle
+{
+
+  /**
+   * Function to call on mapping changes.
+   */
+  GNUNET_NAT_MiniAddressCallback ac;
+
+  /**
+   * Closure for @e ac.
+   */
+  void *ac_cls;
+
+  /**
+   * Command used to install the map.
+   */
+  struct GNUNET_OS_CommandHandle *map_cmd;
+
+  /**
+   * Command used to refresh our map information.
+   */
+  struct GNUNET_OS_CommandHandle *refresh_cmd;
+
+  /**
+   * Command used to remove the mapping.
+   */
+  struct GNUNET_OS_CommandHandle *unmap_cmd;
+
+  /**
+   * Our current external mapping (if we have one).
+   */
+  struct sockaddr_in current_addr;
+
+  /**
+   * We check the mapping periodically to see if it
+   * still works.  This task triggers the check.
+   */
+  struct GNUNET_SCHEDULER_Task * refresh_task;
+
+  /**
+   * Are we mapping TCP or UDP?
+   */
+  int is_tcp;
+
+  /**
+   * Did we succeed with creating a mapping?
+   */
+  int did_map;
+
+  /**
+   * Did we find our mapping during refresh scan?
+   */
+  int found;
+
+  /**
+   * Which port are we mapping?
+   */
+  uint16_t port;
+
+};
+
+
+/**
+ * Run "upnpc -l" to find out if our mapping changed.
+ *
+ * @param cls the `struct GNUNET_NAT_MiniHandle`
+ * @param tc scheduler context
+ */
+static void
+do_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+
+/**
+ * Process the output from the "upnpc -r" command.
+ *
+ * @param cls the `struct GNUNET_NAT_MiniHandle`
+ * @param line line of output, NULL at the end
+ */
+static void
+process_map_output (void *cls, const char *line);
+
+
+/**
+ * Run "upnpc -r" to map our internal port.
+ *
+ * @param mini our handle
+ */
+static void
+run_upnpc_r (struct GNUNET_NAT_MiniHandle *mini)
+{
+  char pstr[6];
+
+  GNUNET_snprintf (pstr,
+                   sizeof (pstr),
+                   "%u",
+                   (unsigned int) mini->port);
+  mini->map_cmd =
+    GNUNET_OS_command_run (&process_map_output, mini, MAP_TIMEOUT,
+                           "upnpc", "upnpc", "-r", pstr,
+                           mini->is_tcp ? "tcp" : "udp", NULL);
+  if (NULL == mini->map_cmd)
+  {
+    mini->ac (mini->ac_cls,
+              GNUNET_SYSERR,
+              NULL, 0,
+              GNUNET_NAT_ERROR_UPNPC_FAILED);
+    return;
+  }
+}
+
+
+/**
+ * Process the output from "upnpc -l" to see if our
+ * external mapping changed.  If so, do the notifications.
+ *
+ * @param cls the `struct GNUNET_NAT_MiniHandle`
+ * @param line line of output, NULL at the end
+ */
+static void
+process_refresh_output (void *cls, const char *line)
+{
+  struct GNUNET_NAT_MiniHandle *mini = cls;
+  char pstr[9];
+  const char *s;
+  unsigned int nport;
+  struct in_addr exip;
+
+  if (NULL == line)
+  {
+    GNUNET_OS_command_stop (mini->refresh_cmd);
+    mini->refresh_cmd = NULL;
+    if (GNUNET_NO == mini->found)
     {
-      buf[off-1] = '\0';
-      if (1 == inet_pton (AF_INET, buf, addr))
-       {
-         if (addr->s_addr == 0)
-           iret = GNUNET_NO; /* got 0.0.0.0 */
-         iret = GNUNET_OK;
-       }
+      /* mapping disappeared, try to re-create */
+      if (GNUNET_YES == mini->did_map)
+      {
+        mini->ac (mini->ac_cls,
+                  GNUNET_NO,
+                  (const struct sockaddr *) &mini->current_addr,
+                  sizeof (mini->current_addr),
+                  GNUNET_NAT_ERROR_SUCCESS);
+        mini->did_map = GNUNET_NO;
+      }
+      run_upnpc_r (mini);
     }
-  (void) GNUNET_OS_process_kill (eip, SIGKILL);
-  GNUNET_OS_process_close (eip);
-  GNUNET_DISK_pipe_close (opipe);
-  return iret; 
+    return;
+  }
+  if (!mini->did_map)
+    return;                     /* never mapped, won't find our mapping anyway */
+
+  /* we're looking for output of the form:
+   * "ExternalIPAddress = 12.134.41.124" */
+
+  s = strstr (line, "ExternalIPAddress = ");
+  if (NULL != s)
+  {
+    s += strlen ("ExternalIPAddress = ");
+    if (1 != inet_pton (AF_INET, s, &exip))
+      return;                   /* skip */
+    if (exip.s_addr == mini->current_addr.sin_addr.s_addr)
+      return;                   /* no change */
+    /* update mapping */
+    mini->ac (mini->ac_cls, GNUNET_NO,
+              (const struct sockaddr *) &mini->current_addr,
+              sizeof (mini->current_addr),
+              GNUNET_NAT_ERROR_SUCCESS);
+    mini->current_addr.sin_addr = exip;
+    mini->ac (mini->ac_cls, GNUNET_YES,
+              (const struct sockaddr *) &mini->current_addr,
+              sizeof (mini->current_addr),
+              GNUNET_NAT_ERROR_SUCCESS);
+    return;
+  }
+  /*
+   * we're looking for output of the form:
+   *
+   * "0 TCP  3000->192.168.2.150:3000  'libminiupnpc' ''"
+   * "1 UDP  3001->192.168.2.150:3001  'libminiupnpc' ''"
+   *
+   * the pattern we look for is:
+   *
+   * "%s TCP  PORT->STRING:OURPORT *" or
+   * "%s UDP  PORT->STRING:OURPORT *"
+   */
+  GNUNET_snprintf (pstr, sizeof (pstr), ":%u ", mini->port);
+  if (NULL == (s = strstr (line, "->")))
+    return;                     /* skip */
+  if (NULL == strstr (s, pstr))
+    return;                     /* skip */
+  if (1 !=
+      SSCANF (line,
+              (mini->is_tcp) ? "%*u TCP  %u->%*s:%*u %*s" :
+              "%*u UDP  %u->%*s:%*u %*s", &nport))
+    return;                     /* skip */
+  mini->found = GNUNET_YES;
+  if (nport == ntohs (mini->current_addr.sin_port))
+    return;                     /* no change */
+
+  /* external port changed, update mapping */
+  mini->ac (mini->ac_cls, GNUNET_NO,
+            (const struct sockaddr *) &mini->current_addr,
+            sizeof (mini->current_addr),
+            GNUNET_NAT_ERROR_SUCCESS);
+  mini->current_addr.sin_port = htons ((uint16_t) nport);
+  mini->ac (mini->ac_cls, GNUNET_YES,
+            (const struct sockaddr *) &mini->current_addr,
+            sizeof (mini->current_addr),
+            GNUNET_NAT_ERROR_SUCCESS);
 }
 
+
+/**
+ * Run "upnpc -l" to find out if our mapping changed.
+ *
+ * @param cls the 'struct GNUNET_NAT_MiniHandle'
+ * @param tc scheduler context
+ */
+static void
+do_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_NAT_MiniHandle *mini = cls;
+  int ac;
+
+  mini->refresh_task =
+    GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ,
+                                  &do_refresh, mini);
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Running `upnpc' to check if our mapping still exists\n");
+  mini->found = GNUNET_NO;
+  ac = GNUNET_NO;
+  if (NULL != mini->map_cmd)
+  {
+    /* took way too long, abort it! */
+    GNUNET_OS_command_stop (mini->map_cmd);
+    mini->map_cmd = NULL;
+    ac = GNUNET_YES;
+  }
+  if (NULL != mini->refresh_cmd)
+  {
+    /* took way too long, abort it! */
+    GNUNET_OS_command_stop (mini->refresh_cmd);
+    mini->refresh_cmd = NULL;
+    ac = GNUNET_YES;
+  }
+  mini->refresh_cmd =
+      GNUNET_OS_command_run (&process_refresh_output, mini, MAP_TIMEOUT,
+                             "upnpc", "upnpc", "-l", NULL);
+  if (GNUNET_YES == ac)
+    mini->ac (mini->ac_cls,
+              GNUNET_SYSERR,
+              NULL, 0,
+              GNUNET_NAT_ERROR_UPNPC_TIMEOUT);
+}
+
+
+/**
+ * Process the output from the 'upnpc -r' command.
+ *
+ * @param cls the `struct GNUNET_NAT_MiniHandle`
+ * @param line line of output, NULL at the end
+ */
+static void
+process_map_output (void *cls,
+                    const char *line)
+{
+  struct GNUNET_NAT_MiniHandle *mini = cls;
+  const char *ipaddr;
+  char *ipa;
+  const char *pstr;
+  unsigned int port;
+
+  if (NULL == line)
+  {
+    GNUNET_OS_command_stop (mini->map_cmd);
+    mini->map_cmd = NULL;
+    if (GNUNET_YES != mini->did_map)
+      mini->ac (mini->ac_cls,
+                GNUNET_SYSERR,
+                NULL, 0,
+                GNUNET_NAT_ERROR_UPNPC_PORTMAP_FAILED);
+    if (NULL == mini->refresh_task)
+      mini->refresh_task =
+        GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, mini);
+    return;
+  }
+  /*
+   * The upnpc output we're after looks like this:
+   *
+   * "external 87.123.42.204:3000 TCP is redirected to internal 192.168.2.150:3000"
+   */
+  if ((NULL == (ipaddr = strstr (line, " "))) ||
+      (NULL == (pstr = strstr (ipaddr, ":"))) ||
+      (1 != SSCANF (pstr + 1, "%u", &port)))
+  {
+    return;                     /* skip line */
+  }
+  ipa = GNUNET_strdup (ipaddr + 1);
+  strstr (ipa, ":")[0] = '\0';
+  if (1 != inet_pton (AF_INET, ipa, &mini->current_addr.sin_addr))
+  {
+    GNUNET_free (ipa);
+    return;                     /* skip line */
+  }
+  GNUNET_free (ipa);
+
+  mini->current_addr.sin_port = htons (port);
+  mini->current_addr.sin_family = AF_INET;
+#if HAVE_SOCKADDR_IN_SIN_LEN
+  mini->current_addr.sin_len = sizeof (struct sockaddr_in);
+#endif
+  mini->did_map = GNUNET_YES;
+  mini->ac (mini->ac_cls, GNUNET_YES,
+            (const struct sockaddr *) &mini->current_addr,
+            sizeof (mini->current_addr),
+            GNUNET_NAT_ERROR_SUCCESS);
+}
+
+
+/**
+ * Start mapping the given port using (mini)upnpc.  This function
+ * should typically not be used directly (it is used within the
+ * general-purpose #GNUNET_NAT_register() code).  However, it can be
+ * used if specifically UPnP-based NAT traversal is to be used or
+ * tested.
+ *
+ * @param port port to map
+ * @param is_tcp #GNUNET_YES to map TCP, #GNUNET_NO for UDP
+ * @param ac function to call with mapping result
+ * @param ac_cls closure for @a ac
+ * @return NULL on error (no 'upnpc' installed)
+ */
+struct GNUNET_NAT_MiniHandle *
+GNUNET_NAT_mini_map_start (uint16_t port,
+                           int is_tcp,
+                           GNUNET_NAT_MiniAddressCallback ac,
+                           void *ac_cls)
+{
+  struct GNUNET_NAT_MiniHandle *ret;
+
+  if (GNUNET_SYSERR ==
+      GNUNET_OS_check_helper_binary ("upnpc", GNUNET_NO, NULL))
+  {
+    LOG (GNUNET_ERROR_TYPE_INFO,
+        _("`upnpc' command not found\n"));
+    ac (ac_cls,
+        GNUNET_SYSERR,
+        NULL, 0,
+        GNUNET_NAT_ERROR_UPNPC_NOT_FOUND);
+    return NULL;
+  }
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Running `upnpc' to install mapping\n");
+  ret = GNUNET_new (struct GNUNET_NAT_MiniHandle);
+  ret->ac = ac;
+  ret->ac_cls = ac_cls;
+  ret->is_tcp = is_tcp;
+  ret->port = port;
+  ret->refresh_task =
+    GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, ret);
+  run_upnpc_r (ret);
+  return ret;
+}
+
+
+/**
+ * Process output from our 'unmap' command.
+ *
+ * @param cls the `struct GNUNET_NAT_MiniHandle`
+ * @param line line of output, NULL at the end
+ */
+static void
+process_unmap_output (void *cls, const char *line)
+{
+  struct GNUNET_NAT_MiniHandle *mini = cls;
+
+  if (NULL == line)
+  {
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "UPnP unmap done\n");
+    GNUNET_OS_command_stop (mini->unmap_cmd);
+    mini->unmap_cmd = NULL;
+    GNUNET_free (mini);
+    return;
+  }
+  /* we don't really care about the output... */
+}
+
+
+/**
+ * Remove a mapping created with (mini)upnpc.  Calling
+ * this function will give 'upnpc' 1s to remove tha mapping,
+ * so while this function is non-blocking, a task will be
+ * left with the scheduler for up to 1s past this call.
+ *
+ * @param mini the handle
+ */
+void
+GNUNET_NAT_mini_map_stop (struct GNUNET_NAT_MiniHandle *mini)
+{
+  char pstr[6];
+
+  if (NULL != mini->refresh_task)
+  {
+    GNUNET_SCHEDULER_cancel (mini->refresh_task);
+    mini->refresh_task = NULL;
+  }
+  if (NULL != mini->refresh_cmd)
+  {
+    GNUNET_OS_command_stop (mini->refresh_cmd);
+    mini->refresh_cmd = NULL;
+  }
+  if (NULL != mini->map_cmd)
+  {
+    GNUNET_OS_command_stop (mini->map_cmd);
+    mini->map_cmd = NULL;
+  }
+  if (GNUNET_NO == mini->did_map)
+  {
+    GNUNET_free (mini);
+    return;
+  }
+  mini->ac (mini->ac_cls, GNUNET_NO,
+            (const struct sockaddr *) &mini->current_addr,
+            sizeof (mini->current_addr),
+            GNUNET_NAT_ERROR_SUCCESS);
+  /* Note: oddly enough, deletion uses the external port whereas
+   * addition uses the internal port; this rarely matters since they
+   * often are the same, but it might... */
+  GNUNET_snprintf (pstr,
+                   sizeof (pstr),
+                   "%u",
+                   (unsigned int) ntohs (mini->current_addr.sin_port));
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Unmapping port %u with UPnP\n",
+       ntohs (mini->current_addr.sin_port));
+  mini->unmap_cmd =
+      GNUNET_OS_command_run (&process_unmap_output, mini, UNMAP_TIMEOUT,
+                             "upnpc", "upnpc", "-d", pstr,
+                             mini->is_tcp ? "tcp" : "udp", NULL);
+}
+
+
 /* end of nat_mini.c */