1 files changed, 333 insertions, 0 deletions

diff --git a/src/nat/nat_mini.c b/src/nat/nat_mini.c
index 2ecdf3575..8f13d298f 100644
--- a/src/nat/nat_mini.c
+++ b/src/nat/nat_mini.c
@@ -28,6 +28,22 @@
 #include "gnunet_nat_lib.h"
 #include "nat.h"
 
+/**
+ * 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, 15)
+
 
 /**
  * Try to get the external IPv4 address of this peer.
@@ -89,5 +105,322 @@ GNUNET_NAT_mini_get_external_ipv4 (struct in_addr *addr)
 }
 
 
+/**
+ * Handle to a mapping created with upnpc.
+ */ 
+struct GNUNET_NAT_MiniHandle
+{
+
+  /**
+   * Function to call on mapping changes.
+   */
+  GNUNET_NAT_AddressCallback ac;
+
+  /**
+   * Closure for '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.
+   */
+  GNUNET_SCHEDULER_TaskIdentifier refresh_task;
+
+  /**
+   * Are we mapping TCP or UDP?
+   */
+  int is_tcp;
+
+  /**
+   * Did we succeed with creating a mapping?
+   */
+  int did_map;
+
+  /**
+   * 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 '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;
+  enum GNUNET_OS_ProcessStatusType type;
+  unsigned long code;
+
+  if (NULL == line)
+    {
+      GNUNET_OS_command_stop (mini->refresh_cmd,
+                              &type, &code);
+      mini->refresh_cmd = NULL;
+      mini->refresh_task = GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ,
+                                                         &do_refresh,
+                                                         mini);
+      return;
+    }
+  /* FIXME: parse 'line' */
+  fprintf (stderr,
+           "Refresh output: `%s'\n",
+           line);
+}
+
+
+/**
+ * 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;
+
+  mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
+  mini->refresh_cmd = GNUNET_OS_command_run (&process_refresh_output,
+                                             mini,
+                                             MAP_TIMEOUT,
+                                             "upnpc",
+                                             "upnpc",
+                                             "-l",
+                                             NULL);
+}
+
+
+/**
+ * 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;
+  enum GNUNET_OS_ProcessStatusType type;
+  unsigned long code;
+  const char *ipaddr;
+  char *ipa;
+  const char *pstr;
+  unsigned int port;
+
+  if (NULL == line)
+    {
+      GNUNET_OS_command_stop (mini->map_cmd,
+                              &type, &code);
+      mini->map_cmd = NULL;
+      if (mini->did_map == GNUNET_YES)
+        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)) )
+    {
+      fprintf (stderr,
+               "Skipping output `%s'\n",
+               line);
+      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);
+      fprintf (stderr,
+               "Skipping output `%s'\n",
+               line);
+      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));
+}
+
+
+/**
+ * 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 'ac'
+ * @return NULL on error
+ */
+struct GNUNET_NAT_MiniHandle *
+GNUNET_NAT_mini_map_start (uint16_t port,
+                           int is_tcp,
+                           GNUNET_NAT_AddressCallback ac,
+                           void *ac_cls)
+{
+  struct GNUNET_NAT_MiniHandle *ret;
+  char pstr[6];
+
+  ret = GNUNET_malloc (sizeof (struct GNUNET_NAT_MiniHandle));
+  ret->ac = ac;
+  ret->ac_cls = ac_cls;
+  ret->is_tcp = is_tcp;
+  ret->port = port;
+  GNUNET_snprintf (pstr, sizeof (pstr),
+                   "%u",
+                   (unsigned int) port);
+  ret->map_cmd = GNUNET_OS_command_run (&process_map_output,
+                                        ret,
+                                        MAP_TIMEOUT,
+                                        "upnpc",
+                                        "upnpc",
+                                        "-r", pstr, 
+                                        is_tcp ? "tcp" : "udp",
+                                        NULL);
+  
+  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;
+  enum GNUNET_OS_ProcessStatusType type;
+  unsigned long code;
+
+  if (NULL == line)
+    {
+      GNUNET_OS_command_stop (mini->unmap_cmd,
+                              &type, &code);
+      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];
+  enum GNUNET_OS_ProcessStatusType type;
+  unsigned long code;
+
+  if (! mini->did_map)
+    {
+      if (mini->map_cmd != NULL)
+        {
+          GNUNET_OS_command_stop (mini->map_cmd, 
+                                  &type, &code);
+          mini->map_cmd = NULL;
+        }
+      GNUNET_free (mini);
+      return;
+    }
+  if (GNUNET_SCHEDULER_NO_TASK != mini->refresh_task)
+    {
+      GNUNET_SCHEDULER_cancel (mini->refresh_task);
+      mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
+    }
+  if (mini->refresh_cmd != NULL)
+    {
+      GNUNET_OS_command_stop (mini->refresh_cmd,
+                              &type, &code);
+      mini->refresh_cmd = NULL;
+    }
+  mini->ac (mini->ac_cls, GNUNET_NO,
+            (const struct sockaddr*) &mini->current_addr,
+            sizeof (mini->current_addr));
+  GNUNET_snprintf (pstr, sizeof (pstr),
+                   "%u",
+                   (unsigned int) mini->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 */