remove legacy NAT library logic, or preserve if it might still be useful

7 files changed, 30 insertions, 4980 deletions

diff --git a/src/nat/Makefile.am b/src/nat/Makefile.am
index 456ddfb62c..3dc001dd79 100644
--- a/src/nat/Makefile.am
+++ b/src/nat/Makefile.am
@@ -60,22 +60,8 @@ if USE_COVERAGE
 endif
 
 lib_LTLIBRARIES = \
-  libgnunetnat.la \
   libgnunetnatnew.la 
 
-libgnunetnat_la_SOURCES = \
-  nat.c nat.h \
-  nat_auto.c \
-  nat_test.c \
-  nat_mini.c \
-  nat_stun.c
-libgnunetnat_la_LIBADD = \
-  $(top_builddir)/src/util/libgnunetutil.la \
-  $(GN_LIBINTL) @EXT_LIBS@ 
-libgnunetnat_la_LDFLAGS = \
-  $(GN_LIB_LDFLAGS) $(WINFLAGS) \
-  -version-info 1:1:1
-
 libgnunetnatnew_la_SOURCES = \
   nat_api.c \
   nat_api_stun.c nat_stun.h \
@@ -100,40 +86,40 @@ gnunet_service_nat_LDADD = \
   -lgcrypt \
   $(GN_LIBINTL)
 
-check_PROGRAMS = \
-  test_nat \
-  test_nat_mini \
-  test_nat_test \
-  test_stun
+#check_PROGRAMS = \
+#  test_nat \
+#  test_nat_mini \
+#  test_nat_test \
+#  test_stun
 
 if ENABLE_TEST_RUN
  AM_TESTS_ENVIRONMENT=export GNUNET_PREFIX=$${GNUNET_PREFIX:-@libdir@};export PATH=$${GNUNET_PREFIX:-@prefix@}/bin:$$PATH;
  TESTS = $(check_PROGRAMS)
 endif
 
-test_nat_SOURCES = \
-  test_nat.c
-test_nat_LDADD = \
- libgnunetnat.la \
- $(top_builddir)/src/util/libgnunetutil.la 
-
-test_nat_mini_SOURCES = \
-  test_nat_mini.c
-test_nat_mini_LDADD = \
- libgnunetnat.la \
- $(top_builddir)/src/util/libgnunetutil.la 
-
-test_nat_test_SOURCES = \
-  test_nat_test.c
-test_nat_test_LDADD = \
- libgnunetnat.la \
- $(top_builddir)/src/util/libgnunetutil.la 
-
-test_stun_SOURCES = \
-  test_stun.c
-test_stun_LDADD = \
- libgnunetnat.la \
- $(top_builddir)/src/util/libgnunetutil.la 
+#test_nat_SOURCES = \
+#  test_nat.c
+#test_nat_LDADD = \
+# libgnunetnat.la \
+# $(top_builddir)/src/util/libgnunetutil.la 
+
+#test_nat_mini_SOURCES = \
+#  test_nat_mini.c
+#test_nat_mini_LDADD = \
+# libgnunetnat.la \
+# $(top_builddir)/src/util/libgnunetutil.la 
+
+#test_nat_test_SOURCES = \
+#  test_nat_test.c
+#test_nat_test_LDADD = \
+# libgnunetnat.la \
+# $(top_builddir)/src/util/libgnunetutil.la 
+
+#test_stun_SOURCES = \
+#  test_stun.c
+#test_stun_LDADD = \
+# libgnunetnat.la \
+# $(top_builddir)/src/util/libgnunetutil.la 
 
 EXTRA_DIST = \
  test_nat_data.conf \
diff --git a/src/nat/gnunet-service-nat.c b/src/nat/gnunet-service-nat.c
index b3e81127b8..7fa329b54e 100644
--- a/src/nat/gnunet-service-nat.c
+++ b/src/nat/gnunet-service-nat.c
@@ -28,13 +28,8 @@
  * knowledge about the local network topology.
  *
  * TODO:
- * - adapt existing transports to use new NAT logic
- * - abandon legacy NAT code
- *
- * - implement "more" autoconfig:
- *   + consider moving autoconfig-logic into separate service! 
- *   + re-work gnunet-nat-server & integrate!
- *   + test manually punched NAT (how?)
+ * - migrate test cases to new NAT service
+ * - add new traceroute-based logic for external IP detection
  *
  * - implement & test STUN processing to classify NAT;
  *   basically, open port & try different methods.
diff --git a/src/nat/nat.c b/src/nat/nat.c
deleted file mode 100644
index 08dd5dd1ec..0000000000
--- a/src/nat/nat.c
+++ /dev/null
@@ -1,2054 +0,0 @@
-/*
-     This file is part of GNUnet.
-     Copyright (C) 2009, 2010, 2011 GNUnet e.V.
-
-     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 3, 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., 51 Franklin Street, Fifth Floor,
-     Boston, MA 02110-1301, USA.
-*/
-
-/**
- * @file nat/nat.c
- * @brief Library handling UPnP and NAT-PMP port forwarding and
- *     external IP address retrieval
- * @author Milan Bouchet-Valat
- * @author Christian Grothoff
- */
-#include "platform.h"
-#include "gnunet_util_lib.h"
-#include "gnunet_resolver_service.h"
-#include "gnunet_nat_lib.h"
-#include "nat.h"
-
-#define LOG(kind,...) GNUNET_log_from (kind, "nat", __VA_ARGS__)
-
-/**
- * How often do we scan for changes in our IP address from our local
- * interfaces?
- */
-#define IFC_SCAN_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
-
-/**
- * How often do we scan for changes in how our hostname resolves?
- */
-#define HOSTNAME_DNS_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 20)
-
-
-/**
- * How often do we scan for changes in how our external (dyndns) hostname resolves?
- */
-#define DYNDNS_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 7)
-
-/**
- * How long until we give up trying to resolve our own hostname?
- */
-#define HOSTNAME_RESOLVE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
-
-
-/**
- * How often do we check a STUN server ?
- */
-#define STUN_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 2)
-
-
-/**
- * Where did the given local address originate from?
- * To be used for debugging as well as in the future
- * to remove all addresses from a certain source when
- * we reevaluate the source.
- */
-enum LocalAddressSource
-{
-  /**
-   * Address was obtained by DNS resolution of the external hostname
-   * given in the configuration (i.e. hole-punched DynDNS setup).
-   */
-  LAL_EXTERNAL_IP,
-
-  /**
-   * Address was obtained by an external STUN server
-   */
-  LAL_EXTERNAL_STUN_IP,
-
-  /**
-   * Address was obtained by DNS resolution of the external hostname
-   * given in the configuration (i.e. hole-punched DynDNS setup)
-   * during the previous iteration (see #3213).
-   */
-  LAL_EXTERNAL_IP_OLD,
-
-  /**
-   * Address was obtained by looking up our own hostname in DNS.
-   */
-  LAL_HOSTNAME_DNS,
-
-  /**
-   * Address was obtained by scanning our hosts's network interfaces
-   * and taking their address (no DNS involved).
-   */
-  LAL_INTERFACE_ADDRESS,
-
-  /**
-   * Addresses we were explicitly bound to.
-   */
-  LAL_BINDTO_ADDRESS,
-
-  /**
-   * Addresses from UPnP or PMP
-   */
-  LAL_UPNP,
-
-  /**
-   * End of the list.
-   */
-  LAL_END
-};
-
-
-/**
- * List of local addresses that we currently deem valid.  Actual
- * struct is followed by the 'struct sockaddr'.  Note that the code
- * intentionally makes no attempt to ensure that a particular address
- * is only listed once (especially since it may come from different
- * sources, and the source is an "internal" construct).
- */
-struct LocalAddressList
-{
-  /**
-   * This is a linked list.
-   */
-  struct LocalAddressList *next;
-
-  /**
-   * Previous entry.
-   */
-  struct LocalAddressList *prev;
-
-  /**
-   * Number of bytes of address that follow.
-   */
-  socklen_t addrlen;
-
-  /**
-   * Origin of the local address.
-   */
-  enum LocalAddressSource source;
-};
-
-
-/**
- * Handle for miniupnp-based NAT traversal actions.
- */
-struct MiniList
-{
-
-  /**
-   * Doubly-linked list.
-   */
-  struct MiniList *next;
-
-  /**
-   * Doubly-linked list.
-   */
-  struct MiniList *prev;
-
-  /**
-   * Handle to mini-action.
-   */
-  struct GNUNET_NAT_MiniHandle *mini;
-
-  /**
-   * Local port number that was mapped.
-   */
-  uint16_t port;
-
-};
-
-
-/**
- * List of STUN servers
- */
-struct StunServerList
-{
-
-  /**
-   * Doubly-linked list.
-   */
-  struct StunServerList *next;
-
-  /**
-   * Doubly-linked list.
-   */
-  struct StunServerList *prev;
-
-  /**
-   * Address
-   */
-  char * address;
-
-  /**
-   * Server Port
-   */
-  uint16_t port;
-
-};
-
-
-/**
- * Handle for active NAT registrations.
- */
-struct GNUNET_NAT_Handle
-{
-
-  /**
-   * Configuration to use.
-   */
-  const struct GNUNET_CONFIGURATION_Handle *cfg;
-
-  /**
-   * Function to call when we learn about a new address.
-   */
-  GNUNET_NAT_AddressCallback address_callback;
-
-  /**
-   * Function to call when we notice another peer asking for
-   * connection reversal.
-   */
-  GNUNET_NAT_ReversalCallback reversal_callback;
-
-  /**
-   * Closure for callbacks (@e address_callback and @e reversal_callback)
-   */
-  void *callback_cls;
-
-  /**
-   * Handle for (DYN)DNS lookup of our external IP.
-   */
-  struct GNUNET_RESOLVER_RequestHandle *ext_dns;
-
-  /**
-   * Handle for request of hostname resolution, non-NULL if pending.
-   */
-  struct GNUNET_RESOLVER_RequestHandle *hostname_dns;
-
-  /**
-   * stdout pipe handle for the gnunet-helper-nat-server process
-   */
-  struct GNUNET_DISK_PipeHandle *server_stdout;
-
-  /**
-   * stdout file handle (for reading) for the gnunet-helper-nat-server process
-   */
-  const struct GNUNET_DISK_FileHandle *server_stdout_handle;
-
-  /**
-   * Linked list of currently valid addresses (head).
-   */
-  struct LocalAddressList *lal_head;
-
-  /**
-   * Linked list of currently valid addresses (tail).
-   */
-  struct LocalAddressList *lal_tail;
-
-  /**
-   * How long do we wait for restarting a crashed gnunet-helper-nat-server?
-   */
-  struct GNUNET_TIME_Relative server_retry_delay;
-
-  /**
-   * ID of select gnunet-helper-nat-server stdout read task
-   */
-  struct GNUNET_SCHEDULER_Task *server_read_task;
-
-  /**
-   * ID of interface IP-scan task
-   */
-  struct GNUNET_SCHEDULER_Task *ifc_task;
-
-  /**
-   * ID of hostname DNS lookup task
-   */
-  struct GNUNET_SCHEDULER_Task *hostname_task;
-
-  /**
-   * ID of DynDNS lookup task
-   */
-  struct GNUNET_SCHEDULER_Task *dns_task;
-
-  /**
-   * Active STUN request, if any.
-   */
-  struct GNUNET_NAT_STUN_Handle *stun_request;
-
-  /**
-   * How often do we scan for changes in our IP address from our local
-   * interfaces?
-   */
-  struct GNUNET_TIME_Relative ifc_scan_frequency;
-
-  /**
-   * How often do we scan for changes in how our hostname resolves?
-   */
-  struct GNUNET_TIME_Relative hostname_dns_frequency;
-
-  /**
-   * How often do we scan for changes in how our external (dyndns) hostname resolves?
-   */
-  struct GNUNET_TIME_Relative dyndns_frequency;
-
-  /**
-   * The process id of the server process (if behind NAT)
-   */
-  struct GNUNET_OS_Process *server_proc;
-
-  /**
-   * LAN address as passed by the caller (array).
-   */
-  struct sockaddr **local_addrs;
-
-  /**
-   * Length of the @e local_addrs.
-   */
-  socklen_t *local_addrlens;
-
-  /**
-   * List of handles for UPnP-traversal, one per local port (if
-   * not IPv6-only).
-   */
-  struct MiniList *mini_head;
-
-  /**
-   * List of handles for UPnP-traversal, one per local port (if
-   * not IPv6-only).
-   */
-  struct MiniList *mini_tail;
-
-  /**
-   * Number of entries in 'local_addrs' array.
-   */
-  unsigned int num_local_addrs;
-
-  /**
-   * Our external address (according to config, UPnP may disagree...),
-   * in dotted decimal notation, IPv4-only. Or NULL if not known.
-   */
-  char *external_address;
-
-  /**
-   * Presumably our internal address (according to config)
-   */
-  char *internal_address;
-
-  /**
-   * Is this transport configured to be behind a NAT?
-   */
-  int behind_nat;
-
-  /**
-   * Has the NAT been punched? (according to config)
-   */
-  int nat_punched;
-
-  /**
-   * Is this transport configured to allow connections to NAT'd peers?
-   */
-  int enable_nat_client;
-
-  /**
-   * Should we run the gnunet-helper-nat-server?
-   */
-  int enable_nat_server;
-
-  /**
-   * Are we allowed to try UPnP/PMP for NAT traversal?
-   */
-  int enable_upnp;
-
-  /**
-   * Should we use local addresses (loopback)? (according to config)
-   */
-  int use_localaddresses;
-
-  /**
-   * Should we return local addresses to clients
-   */
-  int return_localaddress;
-
-  /**
-   * Should we do a DNS lookup of our hostname to find out our own IP?
-   */
-  int use_hostname;
-
-  /**
-   * Is using IPv6 disabled?
-   */
-  int disable_ipv6;
-
-  /**
-   * Is this TCP or UDP?
-   */
-  int is_tcp;
-
-  /**
-   * Port we advertise to the outside.
-   */
-  uint16_t adv_port;
-
-  /**
-   * Should we use STUN ?
-   */
-  int use_stun;
-
-  /**
-   * How often should we check STUN ?
-   */
-  struct GNUNET_TIME_Relative stun_frequency;
-
-  /**
-   * STUN socket
-   */
-  struct GNUNET_NETWORK_Handle* socket;
-
-  /*
-   * Am I waiting for a STUN response ?
-   */
-  int waiting_stun;
-
-  /**
-   * STUN request task
-   */
-  struct GNUNET_SCHEDULER_Task *stun_task;
-
-  /**
-   * Head of List of STUN servers
-   */
-  struct StunServerList *stun_servers_head;
-
-  /**
-   * Tail of List of STUN servers
-   */
-  struct StunServerList *stun_servers_tail;
-
-  /**
-   * Actual STUN Server
-   */
-  struct StunServerList *actual_stun_server;
-
-};
-
-
-/**
- * Try to start the gnunet-helper-nat-server (if it is not
- * already running).
- *
- * @param h handle to NAT
- */
-static void
-start_gnunet_nat_server (struct GNUNET_NAT_Handle *h);
-
-
-/**
- * Remove all addresses from the list of 'local' addresses
- * that originated from the given source.
- *
- * @param h handle to NAT
- * @param src source that identifies addresses to remove
- */
-static void
-remove_from_address_list_by_source (struct GNUNET_NAT_Handle *h,
-                                    enum LocalAddressSource src)
-{
-  struct LocalAddressList *pos;
-  struct LocalAddressList *next;
-
-  next = h->lal_head;
-  while (NULL != (pos = next))
-  {
-    next = pos->next;
-    if (pos->source != src)
-      continue;
-    GNUNET_CONTAINER_DLL_remove (h->lal_head,
-                                 h->lal_tail,
-                                 pos);
-    if (NULL != h->address_callback)
-      h->address_callback (h->callback_cls,
-                           GNUNET_NO,
-                           (const struct sockaddr *) &pos[1],
-                           pos->addrlen);
-    GNUNET_free (pos);
-  }
-}
-
-
-/**
- * Add the given address to the list of 'local' addresses, thereby
- * making it a 'legal' address for this peer to have.
- *
- * @param h handle to NAT
- * @param src where did the local address originate from?
- * @param arg the address, some `struct sockaddr`
- * @param arg_size number of bytes in @a arg
- */
-static void
-add_to_address_list_as_is (struct GNUNET_NAT_Handle *h,
-                           enum LocalAddressSource src,
-                           const struct sockaddr *arg,
-                           socklen_t arg_size)
-{
-  struct LocalAddressList *lal;
-
-  lal = GNUNET_malloc (sizeof (struct LocalAddressList) + arg_size);
-  GNUNET_memcpy (&lal[1], arg, arg_size);
-  lal->addrlen = arg_size;
-  lal->source = src;
-  GNUNET_CONTAINER_DLL_insert (h->lal_head,
-                               h->lal_tail,
-                               lal);
-  LOG (GNUNET_ERROR_TYPE_DEBUG,
-       "Adding address `%s' from source %d\n",
-       GNUNET_a2s (arg, arg_size),
-       src);
-  if (NULL != h->address_callback)
-    h->address_callback (h->callback_cls,
-                         GNUNET_YES,
-                         arg,
-                         arg_size);
-}
-
-
-/**
- * Add the given address to the list of 'local' addresses, thereby
- * making it a 'legal' address for this peer to have.   Set the
- * port number in the process to the advertised port and possibly
- * also to zero (if we have the gnunet-helper-nat-server).
- *
- * @param h handle to NAT
- * @param src where did the local address originate from?
- * @param arg the address, some `struct sockaddr`
- * @param arg_size number of bytes in @a arg
- */
-static void
-add_to_address_list (struct GNUNET_NAT_Handle *h,
-                     enum LocalAddressSource src,
-                     const struct sockaddr *arg,
-                     socklen_t arg_size)
-{
-  struct sockaddr_in s4;
-  const struct sockaddr_in *in4;
-  struct sockaddr_in6 s6;
-  const struct sockaddr_in6 *in6;
-
-  if (arg_size == sizeof (struct sockaddr_in))
-  {
-    in4 = (const struct sockaddr_in *) arg;
-    s4 = *in4;
-    s4.sin_port = htons (h->adv_port);
-    add_to_address_list_as_is (h, src, (const struct sockaddr *) &s4,
-                               sizeof (struct sockaddr_in));
-    if (GNUNET_YES == h->enable_nat_server)
-    {
-      /* also add with PORT = 0 to indicate NAT server is enabled */
-      s4.sin_port = htons (0);
-      add_to_address_list_as_is (h, src, (const struct sockaddr *) &s4,
-                                 sizeof (struct sockaddr_in));
-    }
-  }
-  else if (arg_size == sizeof (struct sockaddr_in6))
-  {
-    if (GNUNET_YES != h->disable_ipv6)
-    {
-      in6 = (const struct sockaddr_in6 *) arg;
-      s6 = *in6;
-      s6.sin6_port = htons (h->adv_port);
-      add_to_address_list_as_is (h, src, (const struct sockaddr *) &s6,
-                                 sizeof (struct sockaddr_in6));
-    }
-  }
-  else
-  {
-    GNUNET_assert (0);
-  }
-}
-
-
-/**
- * Add the given IP address to the list of 'local' addresses, thereby
- * making it a 'legal' address for this peer to have.
- *
- * @param h handle to NAT
- * @param src where did the local address originate from?
- * @param addr the address, some `struct in_addr` or `struct in6_addr`
- * @param addrlen number of bytes in addr
- */
-static void
-add_ip_to_address_list (struct GNUNET_NAT_Handle *h,
-                        enum LocalAddressSource src,
-			const void *addr,
-                        socklen_t addrlen)
-{
-  struct sockaddr_in s4;
-  const struct in_addr *in4;
-  struct sockaddr_in6 s6;
-  const struct in6_addr *in6;
-
-  if (addrlen == sizeof (struct in_addr))
-  {
-    in4 = (const struct in_addr *) addr;
-    memset (&s4, 0, sizeof (s4));
-    s4.sin_family = AF_INET;
-    s4.sin_port = 0;
-#if HAVE_SOCKADDR_IN_SIN_LEN
-    s4.sin_len = (u_char) sizeof (struct sockaddr_in);
-#endif
-    s4.sin_addr = *in4;
-    add_to_address_list (h, src, (const struct sockaddr *) &s4,
-                         sizeof (struct sockaddr_in));
-    if (GNUNET_YES == h->enable_nat_server)
-    {
-      /* also add with PORT = 0 to indicate NAT server is enabled */
-      s4.sin_port = htons (0);
-      add_to_address_list (h, src, (const struct sockaddr *) &s4,
-                           sizeof (struct sockaddr_in));
-
-    }
-  }
-  else if (addrlen == sizeof (struct in6_addr))
-  {
-    if (GNUNET_YES != h->disable_ipv6)
-    {
-      in6 = (const struct in6_addr *) addr;
-      memset (&s6, 0, sizeof (s6));
-      s6.sin6_family = AF_INET6;
-      s6.sin6_port = htons (h->adv_port);
-#if HAVE_SOCKADDR_IN_SIN_LEN
-      s6.sin6_len = (u_char) sizeof (struct sockaddr_in6);
-#endif
-      s6.sin6_addr = *in6;
-      add_to_address_list (h, src, (const struct sockaddr *) &s6,
-                           sizeof (struct sockaddr_in6));
-    }
-  }
-  else
-  {
-    GNUNET_assert (0);
-  }
-}
-
-
-/**
- * Task to do DNS lookup on our external hostname to
- * get DynDNS-IP addresses.
- *
- * @param cls the NAT handle
- */
-static void
-resolve_dns (void *cls);
-
-
-/**
- * Our (external) hostname was resolved and the configuration says that
- * the NAT was hole-punched.
- *
- * @param cls the `struct GNUNET_NAT_Handle`
- * @param addr NULL on error, otherwise result of DNS lookup
- * @param addrlen number of bytes in @a addr
- */
-static void
-process_external_ip (void *cls,
-                     const struct sockaddr *addr,
-                     socklen_t addrlen)
-{
-  struct GNUNET_NAT_Handle *h = cls;
-  struct in_addr dummy;
-
-  if (NULL == addr)
-  {
-    h->ext_dns = NULL;
-    /* Current iteration is over, remove 'old' IPs now */
-    LOG (GNUNET_ERROR_TYPE_DEBUG,
-         "Purging old IPs for external address\n");
-    remove_from_address_list_by_source (h,
-					LAL_EXTERNAL_IP_OLD);
-    if (1 == inet_pton (AF_INET,
-                        h->external_address,
-                        &dummy))
-    {
-      LOG (GNUNET_ERROR_TYPE_DEBUG,
-           "Got numeric IP for external address, not repeating lookup\n");
-      return;                   /* repated lookup pointless: was numeric! */
-    }
-    h->dns_task =
-      GNUNET_SCHEDULER_add_delayed (h->dyndns_frequency,
-                                    &resolve_dns, h);
-    return;
-  }
-  LOG (GNUNET_ERROR_TYPE_DEBUG,
-       "Got IP `%s' for external address `%s'\n",
-       GNUNET_a2s (addr,
-		   addrlen),
-       h->external_address);
-  add_to_address_list (h,
-		       LAL_EXTERNAL_IP,
-		       addr,
-		       addrlen);
-}
-
-
-/**
- * Task to do a lookup on our hostname for IP addresses.
- *
- * @param cls the NAT handle
- */
-static void
-resolve_hostname (void *cls);
-
-
-/**
- * Function called by the resolver for each address obtained from DNS
- * for our own hostname.  Add the addresses to the list of our IP
- * addresses.
- *
- * @param cls closure
- * @param addr one of the addresses of the host, NULL for the last address
- * @param addrlen length of the @a addr
- */
-static void
-process_hostname_ip (void *cls,
-                     const struct sockaddr *addr,
-                     socklen_t addrlen)
-{
-  struct GNUNET_NAT_Handle *h = cls;
-
-  if (NULL == addr)
-  {
-    h->hostname_dns = NULL;
-    h->hostname_task =
-        GNUNET_SCHEDULER_add_delayed (h->hostname_dns_frequency,
-                                      &resolve_hostname,
-				      h);
-    return;
-  }
-  add_to_address_list (h,
-		       LAL_HOSTNAME_DNS,
-		       addr,
-		       addrlen);
-}
-
-
-/**
- * Length of the interface names returned from os_network.c.
- * (in that file, hardcoded at 11).
- */
-#define IF_NAME_LEN 11
-
-
-/**
- * Add the IP of our network interface to the list of
- * our IP addresses.
- *
- * @param cls the `struct GNUNET_NAT_Handle`
- * @param name name of the interface
- * @param isDefault do we think this may be our default interface
- * @param addr address of the interface
- * @param broadcast_addr the broadcast address (can be NULL for unknown or unassigned)
- * @param netmask the network mask (can be NULL for unknown or unassigned))
- * @param addrlen number of bytes in @a addr and @a broadcast_addr
- * @return #GNUNET_OK to continue iterating
- */
-static int
-process_interfaces (void *cls,
-                    const char *name,
-                    int isDefault,
-                    const struct sockaddr *addr,
-                    const struct sockaddr *broadcast_addr,
-                    const struct sockaddr *netmask,
-                    socklen_t addrlen)
-{
-  const static struct in6_addr any6 = IN6ADDR_ANY_INIT;
-  struct GNUNET_NAT_Handle *h = cls;
-  const struct sockaddr_in *s4;
-  const struct sockaddr_in6 *s6;
-  const void *ip;
-  char buf[INET6_ADDRSTRLEN];
-  unsigned int i;
-  int have_any;
-  char *tun_if;
-
-  /* skip virtual interfaces created by GNUnet-vpn */
-  if (GNUNET_OK ==
-      GNUNET_CONFIGURATION_get_value_string (h->cfg,
-                                             "vpn",
-                                             "IFNAME",
-                                             &tun_if))
-  {
-    if (0 == strncasecmp (name,
-                          tun_if,
-                          IF_NAME_LEN))
-    {
-      GNUNET_free (tun_if);
-      return GNUNET_OK;
-    }
-    GNUNET_free (tun_if);
-  }
-  /* skip virtual interfaces created by GNUnet-dns */
-  if (GNUNET_OK ==
-      GNUNET_CONFIGURATION_get_value_string (h->cfg,
-                                             "dns",
-                                             "IFNAME",
-                                             &tun_if))
-  {
-    if (0 == strncasecmp (name,
-                          tun_if,
-                          IF_NAME_LEN))
-    {
-      GNUNET_free (tun_if);
-      return GNUNET_OK;
-    }
-    GNUNET_free (tun_if);
-  }
-  /* skip virtual interfaces created by GNUnet-exit */
-  if (GNUNET_OK ==
-      GNUNET_CONFIGURATION_get_value_string (h->cfg,
-                                             "exit",
-                                             "TUN_IFNAME",
-                                             &tun_if))
-  {
-    if (0 == strncasecmp (name,
-                          tun_if,
-                          IF_NAME_LEN))
-    {
-      GNUNET_free (tun_if);
-      return GNUNET_OK;
-    }
-    GNUNET_free (tun_if);
-  }
-
-  switch (addr->sa_family)
-  {
-  case AF_INET:
-    /* check if we're bound to the "ANY" IP address */
-    have_any = GNUNET_NO;
-    for (i=0;i<h->num_local_addrs;i++)
-      {
-	if (h->local_addrs[i]->sa_family != AF_INET)
-	  continue;
-#ifndef INADDR_ANY
-#define INADDR_ANY 0
-#endif
-	if (INADDR_ANY == ((struct sockaddr_in*) h->local_addrs[i])->sin_addr.s_addr)
-	  {
-	    have_any = GNUNET_YES;
-	    break;
-	  }
-      }
-    if (GNUNET_NO == have_any)
-      return GNUNET_OK; /* not bound to IP 0.0.0.0 but to specific IP addresses,
-			   do not use those from interfaces */
-    s4 = (struct sockaddr_in *) addr;
-    ip = &s4->sin_addr;
-
-    /* Check if address is in 127.0.0.0/8 */
-    uint32_t address = ntohl ((uint32_t) (s4->sin_addr.s_addr));
-    uint32_t value = (address & 0xFF000000) ^ 0x7F000000;
-
-    if ((h->return_localaddress == GNUNET_NO) && (value == 0))
-    {
-      return GNUNET_OK;
-    }
-    if ((GNUNET_YES == h->use_localaddresses) || (value != 0))
-    {
-      add_ip_to_address_list (h, LAL_INTERFACE_ADDRESS, &s4->sin_addr,
-                              sizeof (struct in_addr));
-    }
-    break;
-  case AF_INET6:
-    /* check if we're bound to the "ANY" IP address */
-    have_any = GNUNET_NO;
-    for (i=0;i<h->num_local_addrs;i++)
-      {
-	if (h->local_addrs[i]->sa_family != AF_INET6)
-	  continue;
-	if (0 == memcmp (&any6,
-			 &((struct sockaddr_in6*) h->local_addrs[i])->sin6_addr,
-			 sizeof (struct in6_addr)))
-	  {
-	    have_any = GNUNET_YES;
-	    break;
-	  }
-      }
-    if (GNUNET_NO == have_any)
-      return GNUNET_OK; /* not bound to "ANY" IP (::0) but to specific IP addresses,
-			   do not use those from interfaces */
-
-    s6 = (struct sockaddr_in6 *) addr;
-    if (IN6_IS_ADDR_LINKLOCAL (&((struct sockaddr_in6 *) addr)->sin6_addr))
-    {
-      /* skip link local addresses */
-      return GNUNET_OK;
-    }
-    if ((h->return_localaddress == GNUNET_NO) &&
-        (IN6_IS_ADDR_LOOPBACK (&((struct sockaddr_in6 *) addr)->sin6_addr)))
-    {
-      return GNUNET_OK;
-    }
-    ip = &s6->sin6_addr;
-    if (GNUNET_YES == h->use_localaddresses)
-    {
-      add_ip_to_address_list (h, LAL_INTERFACE_ADDRESS, &s6->sin6_addr,
-                              sizeof (struct in6_addr));
-    }
-    break;
-  default:
-    GNUNET_break (0);
-    return GNUNET_OK;
-  }
-  if ( (h->internal_address == NULL) &&
-       (h->server_proc == NULL) &&
-       (h->server_read_task == NULL) &&
-       (GNUNET_YES == isDefault) &&
-       ( (addr->sa_family == AF_INET) ||
-	 (addr->sa_family == AF_INET6) ) )
-  {
-    /* no internal address configured, but we found a "default"
-     * interface, try using that as our 'internal' address */
-    h->internal_address =
-        GNUNET_strdup (inet_ntop (addr->sa_family, ip, buf, sizeof (buf)));
-    start_gnunet_nat_server (h);
-  }
-  return GNUNET_OK;
-}
-
-
-/**
- * Task that restarts the gnunet-helper-nat-server process after a crash
- * after a certain delay.
- *
- * @param cls the `struct GNUNET_NAT_Handle`
- */
-static void
-restart_nat_server (void *cls)
-{
-  struct GNUNET_NAT_Handle *h = cls;
-
-  h->server_read_task = NULL;
-  start_gnunet_nat_server (h);
-}
-
-
-/**
- * We have been notified that gnunet-helper-nat-server has written
- * something to stdout.  Handle the output, then reschedule this
- * function to be called again once more is available.
- *
- * @param cls the NAT handle
- */
-static void
-nat_server_read (void *cls)
-{
-  struct GNUNET_NAT_Handle *h = cls;
-  char mybuf[40];
-  ssize_t bytes;
-  size_t i;
-  int port;
-  const char *port_start;
-  struct sockaddr_in sin_addr;
-
-  h->server_read_task = NULL;
-  memset (mybuf, 0, sizeof (mybuf));
-  bytes =
-    GNUNET_DISK_file_read (h->server_stdout_handle, mybuf, sizeof (mybuf));
-  if (bytes < 1)
-  {
-    LOG (GNUNET_ERROR_TYPE_DEBUG,
-         "Finished reading from server stdout with code: %d\n",
-         bytes);
-    if (0 != GNUNET_OS_process_kill (h->server_proc, GNUNET_TERM_SIG))
-      GNUNET_log_from_strerror (GNUNET_ERROR_TYPE_WARNING, "nat", "kill");
-    GNUNET_OS_process_wait (h->server_proc);
-    GNUNET_OS_process_destroy (h->server_proc);
-    h->server_proc = NULL;
-    GNUNET_DISK_pipe_close (h->server_stdout);
-    h->server_stdout = NULL;
-    h->server_stdout_handle = NULL;
-    /* now try to restart it */
-    h->server_retry_delay = GNUNET_TIME_STD_BACKOFF (h->server_retry_delay);
-    h->server_read_task =
-        GNUNET_SCHEDULER_add_delayed (h->server_retry_delay,
-                                      &restart_nat_server, h);
-    return;
-  }
-
-  port_start = NULL;
-  for (i = 0; i < sizeof (mybuf); i++)
-  {
-    if (mybuf[i] == '\n')
-    {
-      mybuf[i] = '\0';
-      break;
-    }
-    if ((mybuf[i] == ':') && (i + 1 < sizeof (mybuf)))
-    {
-      mybuf[i] = '\0';
-      port_start = &mybuf[i + 1];
-    }
-  }
-
-  /* construct socket address of sender */
-  memset (&sin_addr, 0, sizeof (sin_addr));
-  sin_addr.sin_family = AF_INET;
-#if HAVE_SOCKADDR_IN_SIN_LEN
-  sin_addr.sin_len = sizeof (sin_addr);
-#endif
-  if ((NULL == port_start) || (1 != SSCANF (port_start, "%d", &port)) ||
-      (-1 == inet_pton (AF_INET, mybuf, &sin_addr.sin_addr)))
-  {
-    /* should we restart gnunet-helper-nat-server? */
-    LOG (GNUNET_ERROR_TYPE_WARNING, "nat",
-         _("gnunet-helper-nat-server generated malformed address `%s'\n"),
-         mybuf);
-    h->server_read_task =
-        GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
-                                        h->server_stdout_handle,
-                                        &nat_server_read, h);
-    return;
-  }
-  sin_addr.sin_port = htons ((uint16_t) port);
-  LOG (GNUNET_ERROR_TYPE_DEBUG, "gnunet-helper-nat-server read: %s:%d\n", mybuf,
-       port);
-  h->reversal_callback (h->callback_cls, (const struct sockaddr *) &sin_addr,
-                        sizeof (sin_addr));
-  h->server_read_task =
-      GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
-                                      h->server_stdout_handle,
-				      &nat_s