[GNUnet-SVN] r11637 - gnunet/src/transport

[gnunet]

Author: nevans
Date: 2010-06-08 15:27:51 +0200 (Tue, 08 Jun 2010)
New Revision: 11637

Removed:
   gnunet/src/transport/gnunet-nat-client-udp.c
   gnunet/src/transport/gnunet-nat-server-udp.c
Log:
remove unneeded udp crapulence

Deleted: gnunet/src/transport/gnunet-nat-client-udp.c
===================================================================
--- gnunet/src/transport/gnunet-nat-client-udp.c        2010-06-08 13:27:11 UTC 
(rev 11636)
+++ gnunet/src/transport/gnunet-nat-client-udp.c        2010-06-08 13:27:51 UTC 
(rev 11637)
@@ -1,375 +0,0 @@
-/*
-     This file is part of GNUnet.
-     (C) 2010 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
-     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., 59 Temple Place - Suite 330,
-     Boston, MA 02111-1307, USA.
-*/
-
-/**
- * @file src/transport/gnunet-nat-client-udp.c
- * @brief Tool to help bypass NATs using ICMP method; must run as root (SUID 
will do)
- *        This code will work under GNU/Linux only.  
- * @author Christian Grothoff
- *
- * This program will send ONE ICMP message using RAW sockets
- * to the IP address specified as the second argument.  The ICMP
- * message will have as it's payload a UDP packet.  Since
- * it uses RAW sockets, it must be installed SUID or run as 'root'.
- * In order to keep the security risk of the resulting SUID binary
- * minimal, the program ONLY opens the RAW socket with root
- * privileges, then drops them and only then starts to process
- * command line arguments.  The code also does not link against
- * any shared libraries (except libc) and is strictly minimal
- * (except for checking for errors).  The following list of people
- * have reviewed this code and considered it safe since the last
- * modification (if you reviewed it, please have your name added
- * to the list):
- *
- * - Christian Grothoff
- */
-#define _GNU_SOURCE
-#include <sys/types.h> 
-#include <sys/socket.h>
-#include <arpa/inet.h>
-#include <sys/types.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <string.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <netinet/ip.h>
-#include <netinet/ip_icmp.h>
-#include <netinet/in.h> 
-
-/**
- * Must match IP given in the server.
- */
-#define DUMMY_IP "1.2.3.4"
-#define HAVE_PORT 1
-
-/**
- * Port we always try to use.
- */
-#define NAT_TRAV_PORT 22225
-
-struct ip_packet 
-{
-  uint8_t vers_ihl;
-  uint8_t tos;
-  uint16_t pkt_len;
-  uint16_t id;
-  uint16_t flags_frag_offset;
-  uint8_t ttl;
-  uint8_t proto;
-  uint16_t checksum;
-  uint32_t src_ip;
-  uint32_t dst_ip;
-};
-
-struct icmp_packet 
-{
-  uint8_t type;
-  uint8_t code;
-  uint16_t checksum;
-  uint32_t reserved;
-
-};
-
-struct icmp_echo_packet
-{
-  uint8_t type;
-  uint8_t code;
-  uint16_t checksum;
-  uint32_t reserved;
-  uint32_t data;
-};
-
-struct udp_packet
-{
-  uint16_t src_port;
-
-  uint16_t dst_port;
-
-  uint32_t length;
-};
-
- 
-static int rawsock;
-
-static struct in_addr dummy;
- 
-static struct in_addr target;
-
-#if HAVE_PORT
-  static uint32_t port;
-#endif
-
-static uint16_t 
-calc_checksum(const uint16_t *data, 
-             unsigned int bytes)
-{
-  uint32_t sum;
-  unsigned int i;
-
-  sum = 0;
-  for (i=0;i<bytes/2;i++) 
-    sum += data[i];        
-  sum = (sum & 0xffff) + (sum >> 16);
-  sum = htons(0xffff - sum);
-  return sum;
-}
-
-/**
- * Send an ICMP message to the target.
- *
- * @param my_ip source address
- * @param other target address
- */
-static void
-send_icmp (const struct in_addr *my_ip,
-          const struct in_addr *other)
-{
-  struct ip_packet ip_pkt;
-  struct icmp_packet icmp_pkt;
-  struct udp_packet udp_pkt;
-
-  struct sockaddr_in dst;
-  char packet[sizeof(ip_pkt) * 2 + sizeof(icmp_pkt) * 2 + sizeof(char)];
-
-#if ORIGINAL
-#if HAVE_PORT
-  char packet[sizeof (struct ip_packet)*2 + sizeof (struct icmp_packet) + 
sizeof(struct icmp_echo_packet)];
-#else
-  char packet[sizeof (struct ip_packet)*2 + sizeof (struct icmp_packet)*2];
-#endif
-#endif
-  size_t off;
-  int err;
-
-  /* ip header: send to (known) ip address */
-#if ORIGINAL
-  off = 0;
-  memset(&ip_pkt, 0, sizeof(ip_pkt));
-  ip_pkt.vers_ihl = 0x45;
-  ip_pkt.tos = 0;
-  ip_pkt.pkt_len = sizeof (packet); /* huh? */
-  ip_pkt.id = 1; 
-  ip_pkt.flags_frag_offset = 0;
-  ip_pkt.ttl = IPDEFTTL;
-  ip_pkt.proto = IPPROTO_ICMP;
-  ip_pkt.checksum = 0; 
-  ip_pkt.src_ip = my_ip->s_addr;
-  ip_pkt.dst_ip = other->s_addr;
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (struct 
ip_packet)));
-  memcpy (packet, &ip_pkt, sizeof (struct ip_packet));
-  off += sizeof (ip_pkt);
-  /* icmp reply: time exceeded */
-  icmp_pkt = (struct icmp_packet*) &packet[off];
-  memset(icmp_pkt, 0, sizeof(struct icmp_packet));
-  icmp_pkt->type = ICMP_TIME_EXCEEDED;
-  icmp_pkt->code = 0; 
-  icmp_pkt->reserved = 0;
-  icmp_pkt->checksum = 0;
-
-  off += sizeof (struct icmp_packet);
-#endif
-
-  off = 0;
-  memset(&ip_pkt, 0, sizeof(ip_pkt));
-  ip_pkt.vers_ihl = 0x45;
-  ip_pkt.tos = 0;
-  ip_pkt.pkt_len = htons(sizeof (packet));
-  ip_pkt.id = htons(256);
-  ip_pkt.flags_frag_offset = 0;
-  ip_pkt.ttl = 128;
-  ip_pkt.proto = IPPROTO_ICMP;
-  ip_pkt.checksum = 0;
-  ip_pkt.src_ip = my_ip->s_addr;
-  ip_pkt.dst_ip = other->s_addr;
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (ip_pkt)));
-  memcpy(&packet[off], &ip_pkt, sizeof(ip_pkt));
-  off += sizeof(ip_pkt);
-
-  /* ip header of the presumably 'lost' udp packet */
-  ip_pkt.vers_ihl = 0x45;
-  ip_pkt.tos = 0;
-#if HAVE_PORT
-  ip_pkt.pkt_len = (sizeof (struct ip_packet) + sizeof (struct 
icmp_echo_packet));
-#else
-  ip_pkt.pkt_len = (sizeof (struct ip_packet) + sizeof (struct icmp_packet));
-#endif
-
-  icmp_pkt.type = 11; // TTL exceeded
-  icmp_pkt.code = 0;
-  icmp_pkt.checksum = 0;
-  icmp_pkt.reserved = 0;
-  memcpy(&packet[off], &icmp_pkt, sizeof(icmp_pkt));
-  off += sizeof(icmp_pkt);
-
-
-  // build inner IP header
-  memset(&ip_pkt, 0, sizeof(ip_pkt));
-  ip_pkt.vers_ihl = 0x45;
-  ip_pkt.tos = 0;
-  ip_pkt.pkt_len = htons(sizeof (ip_pkt) + sizeof(udp_pkt));
-  ip_pkt.id = htons(0);
-  ip_pkt.flags_frag_offset = 0;
-  ip_pkt.ttl = 128;
-  ip_pkt.proto = IPPROTO_UDP;
-  ip_pkt.checksum = 0;
-  ip_pkt.src_ip = other->s_addr;
-  ip_pkt.dst_ip = dummy.s_addr;
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (ip_pkt)));
-  memcpy(&packet[off], &ip_pkt, sizeof(ip_pkt));
-  off += sizeof(ip_pkt);
-
-  // build UDP header
-  udp_pkt.src_port = htons(NAT_TRAV_PORT); /* FIXME: does this port matter? */
-  udp_pkt.dst_port = htons(NAT_TRAV_PORT);
-  uint32_t newval = inet_addr("1.2.3.4");
-  memcpy(&udp_pkt.length, &newval, sizeof(uint32_t));
-  memcpy(&packet[off], &udp_pkt, sizeof(udp_pkt));
-  off += sizeof(udp_pkt);
-
-
-
-  // set ICMP checksum
-  icmp_pkt.checksum = htons(calc_checksum((uint16_t*)&packet[sizeof(ip_pkt)],
-                            sizeof (icmp_pkt) + sizeof(ip_pkt) + 
sizeof(udp_pkt)));
-  memcpy (&packet[sizeof(ip_pkt)], &icmp_pkt, sizeof (icmp_pkt));
-
-  /* End of new code */
-#if ORIGINAL
-  ip_pkt.id = 1; 
-  ip_pkt.flags_frag_offset = 0;
-  ip_pkt.ttl = 1; /* real TTL would be 1 on a time exceeded packet */
-  ip_pkt.proto = IPPROTO_ICMP;
-  ip_pkt.src_ip = other->s_addr;
-  ip_pkt.dst_ip = dummy.s_addr;
-  ip_pkt.checksum = 0;
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (struct 
ip_packet)));  
-  memcpy (&packet[off], &ip_pkt, sizeof (struct ip_packet));
-  off += sizeof (struct ip_packet);
-
-
-#if HAVE_PORT
-  icmp_pkt->checksum = htons(calc_checksum((uint16_t*)icmp_pkt,
-                                             sizeof (struct icmp_packet) + 
sizeof(struct ip_packet) + sizeof(struct icmp_echo_packet)));
-
-#else
-  icmp_pkt->checksum = htons(calc_checksum((uint16_t*)icmp_pkt, 
-                                             sizeof (struct icmp_packet)*2 + 
sizeof(struct ip_packet)));
-
-#endif
-
-
-#endif
-
-  memset (&dst, 0, sizeof (dst));
-  dst.sin_family = AF_INET;
-  dst.sin_addr = *other;
-  err = sendto(rawsock, 
-              packet, 
-              off, 0, 
-              (struct sockaddr*)&dst, 
-              sizeof(dst)); /* or sizeof 'struct sockaddr'? */
-  if (err < 0) 
-    {
-      fprintf(stderr,
-             "sendto failed: %s\n", strerror(errno));
-    }
-  else if (err != off) 
-    {
-      fprintf(stderr,
-             "Error: partial send of ICMP message\n");
-    }
-}
-
-
-static int
-make_raw_socket ()
-{
-  const int one = 1;
-  int ret;
-
-  ret = socket (AF_INET, SOCK_RAW, IPPROTO_RAW);
-  if (-1 == ret)
-    {
-      fprintf (stderr,
-              "Error opening RAW socket: %s\n",
-              strerror (errno));
-      return -1;
-    }  
-  if (setsockopt(ret, SOL_SOCKET, SO_BROADCAST,
-                (char *)&one, sizeof(one)) == -1)
-    fprintf(stderr,
-           "setsockopt failed: %s\n",
-           strerror (errno));
-  if (setsockopt(ret, IPPROTO_IP, IP_HDRINCL,
-                (char *)&one, sizeof(one)) == -1)
-    fprintf(stderr,
-           "setsockopt failed: %s\n",
-           strerror (errno));
-  return ret;
-}
-
-
-int
-main (int argc, char *const *argv)
-{
-  struct in_addr external;
-  uid_t uid;
-
-  if (-1 == (rawsock = make_raw_socket()))
-    return 1;     
-  uid = getuid ();
-  if (0 != setresuid (uid, uid, uid))
-    fprintf (stderr,
-            "Failed to setresuid: %s\n",
-            strerror (errno));
-#if HAVE_PORT
-  if (argc != 4)
-    {
-      fprintf (stderr,
-              "This program must be started with our IP, the targets external 
IP, and our port as arguments.\n");
-      return 1;
-    }
-  port = atoi(argv[3]);
-#else
-  if (argc != 3)
-    {
-      fprintf (stderr,
-               "This program must be started with our IP and the targets 
external IP as arguments.\n");
-      return 1;
-    }
-#endif
-  if ( (1 != inet_pton (AF_INET, argv[1], &external)) ||
-       (1 != inet_pton (AF_INET, argv[2], &target)) )
-    {
-      fprintf (stderr,
-              "Error parsing IPv4 address: %s\n",
-              strerror (errno));
-      return 1;
-    }
-  if (1 != inet_pton (AF_INET, DUMMY_IP, &dummy)) abort ();
-  send_icmp (&external,
-            &target);
-  close (rawsock);
-  return 0;
-}
-
-/* end of gnunet-nat-client-udp.c */

Deleted: gnunet/src/transport/gnunet-nat-server-udp.c
===================================================================
--- gnunet/src/transport/gnunet-nat-server-udp.c        2010-06-08 13:27:11 UTC 
(rev 11636)
+++ gnunet/src/transport/gnunet-nat-server-udp.c        2010-06-08 13:27:51 UTC 
(rev 11637)
@@ -1,422 +0,0 @@
-/*
-     This file is part of GNUnet.
-     (C) 2010 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
-     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., 59 Temple Place - Suite 330,
-     Boston, MA 02111-1307, USA.
-*/
-
-/**
- * @file src/transport/gnunet-nat-server-udp.c
- * @brief  This program will send ONE UDP message every 500 ms
- *         to a DUMMY IP address and also listens for ICMP replies.
- *
- * @author Christian Grothoff
- */
-#include <sys/types.h> 
-#include <sys/socket.h>
-#include <arpa/inet.h>
-#include <sys/types.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <string.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <netinet/in.h> 
-#include <time.h>
-
-
-#define DUMMY_IP "1.2.3.4"
-
-/**
- * How often do we send our UDP message to keep ports open (and to
- * try to connect, of course).
- */
-#define UDP_SEND_FREQUENCY_MS 500
-
-/**
- * Port we always try to use.
- */
-#define NAT_TRAV_PORT 22225
-
-/**
- * Number of UDP ports to send to
- */
-#define NUM_UDP_PORTS 1
-
-/**
- * How often do we retry to open and bind a UDP socket before giving up?
- */
-#define MAX_BIND_TRIES 10
-
-#define LOW_PORT 32768
-
-static struct in_addr dummy;
-
-static int icmpsock;
-
-struct icmp_packet
-{
-  uint8_t type;
-  uint8_t code;
-  uint16_t checksum;
-  uint32_t reserved;
-
-};
-
-struct udp_packet
-{
-  uint16_t src_port;
-
-  uint16_t dst_port;
-
-  uint32_t length;
-};
-
-struct ip_packet
-{
-  uint8_t vers_ihl;
-  uint8_t tos;
-  uint16_t pkt_len;
-  uint16_t id;
-  uint16_t flags_frag_offset;
-  uint8_t ttl;
-  uint8_t proto;
-  uint16_t checksum;
-  uint32_t src_ip;
-  uint32_t dst_ip;
-};
-
-#if DUMMY
-static uint16_t
-calc_checksum(const uint16_t *data,
-              unsigned int bytes)
-{
-  uint32_t sum;
-  unsigned int i;
-
-  sum = 0;
-  for (i=0;i<bytes/2;i++)
-    sum += data[i];
-  sum = (sum & 0xffff) + (sum >> 16);
-  sum = htons(0xffff - sum);
-  return sum;
-}
-#endif
-
-/**
- * create a fresh udp socket bound to the NAT_TRAV_PORT.
- *
- * @return -1 on error
- */
-static int
-make_udp_socket ()
-{
-  int ret;
-  int tries;
-  struct sockaddr_in src;
-
-  for (tries=0; tries<MAX_BIND_TRIES; tries++)
-    {
-      ret = socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP);
-      if (-1 == ret)
-        {
-          fprintf (stderr,
-                   "Error opening udp socket: %s\n",
-                   strerror (errno));
-          return -1;
-        }
-      if (ret >= FD_SETSIZE)
-        {
-          fprintf (stderr,
-                   "Socket number too large (%d > %u)\n",
-                   ret,
-                   (unsigned int) FD_SETSIZE);
-          close (ret);
-          return -1;
-        }
-      memset (&src, 0, sizeof (src));
-      src.sin_family = AF_INET;
-      src.sin_port = htons (NAT_TRAV_PORT);
-
-      if (0 != bind (ret, (struct sockaddr*) &src, sizeof (src)))
-        {
-          close (ret);
-          continue;
-        }
-      return ret;
-    }
-  fprintf (stderr,
-           "Error binding udp socket: %s\n",
-           strerror (errno));
-  return -1;
-}
-
-#define LOW_PORT 32768
-
-/**
- * create a random port number that is not totally
- * unlikely to be chosen by the nat box.
- */
-static uint16_t
-make_port ()
-{
-  return LOW_PORT + ( (unsigned int)rand ()) % (64 * 1024 - LOW_PORT - 2);
-}
-
-static int
-make_icmp_socket ()
-{
-  int ret;
-
-  ret = socket (AF_INET, SOCK_RAW, IPPROTO_ICMP);
-  if (-1 == ret)
-    {
-      fprintf (stderr,
-               "Error opening RAW socket: %s\n",
-               strerror (errno));
-      return -1;
-    }
-  if (ret >= FD_SETSIZE)
-    {
-      fprintf (stderr,
-               "Socket number too large (%d > %u)\n",
-               ret,
-               (unsigned int) FD_SETSIZE);
-      close (ret);
-      return -1;
-    }
-  return ret;
-}
-
-#if DUMMY
-/**
- * Send a UDP message to the dummy IP.
- *
- * @param my_ip source address (our ip address)
- */
-static void
-send_dummy_udp (const struct in_addr *my_ip)
-{
-  struct sockaddr_in dst;
-  size_t off;
-  int err;
-  struct ip_packet ip_pkt;
-  struct ip_packet udp_pkt;
-  char packet[sizeof (ip_pkt) + sizeof (udp_pkt)];
-
-
-  // build inner IP header
-  memset(&ip_pkt, 0, sizeof(ip_pkt));
-  ip_pkt.vers_ihl = 0x45;
-  ip_pkt.tos = 0;
-  ip_pkt.pkt_len = htons(sizeof (ip_pkt) + sizeof(udp_pkt));
-  ip_pkt.id = htons(0);
-  ip_pkt.flags_frag_offset = 0;
-  ip_pkt.ttl = 128;
-  ip_pkt.proto = IPPROTO_UDP;
-  ip_pkt.checksum = 0;
-  ip_pkt.src_ip = my_ip->s_addr;
-  ip_pkt.dst_ip = inet_addr(dummy.s_addr);
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (ip_pkt)));
-  memcpy(&packet[off], &ip_pkt, sizeof(ip_pkt));
-  off += sizeof(ip_pkt);
-
-  // build UDP header
-  udp_pkt.src_port = NAT_TRAV_PORT;
-  udp_pkt.dst_port = htons(NAT_TRAV_PORT);
-
-  uint32_t newval = inet_addr("1.2.3.4");
-  memcpy(&udp_pkt.length, &newval, sizeof(uint32_t));
-
-  off += sizeof(udp_pkt);
-
-  err = sendto(rawsock,
-               ip_pkt, off, 0,
-               (struct sockaddr*)&dst,
-               sizeof(dst));
-  if (err < 0)
-    {
-#if VERBOSE
-      fprintf(stderr,
-              "sendto failed: %s\n", strerror(errno));
-#endif
-    }
-  else if (err != off)
-    {
-      fprintf(stderr,
-              "Error: partial send of UDP message\n");
-    }
-}
-#endif
-
-static void
-process_icmp_response()
-{
-  char buf[65536];
-  ssize_t have;
-  struct in_addr sip;
-  struct ip_packet ip_pkt;
-  struct icmp_packet icmp_pkt;
-  size_t off;
-  int have_port;
-  //uint32_t port;
-
-  have = read (icmpsock, buf, sizeof (buf));
-  if (have == -1)
-    {
-      fprintf (stderr,
-               "Error reading raw socket: %s\n",
-               strerror (errno));
-      return;
-    }
-
-  off = 0;
-  memcpy (&ip_pkt, &buf[off], sizeof (ip_pkt));
-  off += sizeof (ip_pkt);
-  memcpy (&icmp_pkt, &buf[off], sizeof (icmp_pkt));
-  off += sizeof (icmp_pkt);
-  if ( (ip_pkt.proto != IPPROTO_ICMP) ||
-       (icmp_pkt.type != 11) ||
-       (icmp_pkt.code != 0) )
-    {
-      /* maybe we got an actual reply back... */
-      return;
-    }
-
-  memcpy(&sip,
-         &ip_pkt.src_ip,
-         sizeof (sip));
-
-  fprintf (stderr,
-           "Received ICMP message of size: %u bytes from %s\n",
-           (unsigned int) have,
-           inet_ntop (AF_INET,
-                      &sip,
-                      buf,
-                      sizeof (buf)));
-
-  have_port = 0;
-  if (have == sizeof (struct ip_packet) *2 + sizeof (struct icmp_packet) * 2 + 
sizeof(uint32_t))
-    {
-      have_port = 1;
-    }
-  else if (have != sizeof (struct ip_packet) *2 + sizeof (struct icmp_packet) 
* 2)
-    {
-#if VERBOSE
-      fprintf (stderr,
-               "Received ICMP message of unexpected size: %u bytes\n",
-               (unsigned int) have);
-#endif
-      return;
-    }
-}
-
-int
-main (int argc, char *const *argv)
-{
-  int udpsocks[NUM_UDP_PORTS];
-  struct in_addr external;
-  unsigned int pos;
-  int i;
-  struct sockaddr_in dst;
-  int first_round = 1;
-  unsigned int tries;
-  struct timeval tv;
-  fd_set rs;
-  time_t stime;
- 
-  if (argc != 2)
-    {
-      fprintf (stderr,
-              "This program must be started with our (internal) IP as the 
single argument.\n");
-      return 1;
-    }
-  if ( (1 != inet_pton (AF_INET, argv[1], &external)))
-    {
-      fprintf (stderr,
-              "Error parsing IPv4 address: %s\n",
-              strerror (errno));
-      return 1;
-    }
-
-  if (1 != inet_pton (AF_INET, DUMMY_IP, &dummy)) abort ();
-
-  fprintf (stderr,
-          "Trying to connect to %s\n",
-          DUMMY_IP);
-  srand (stime = time(NULL));
-  for (i=0;i<NUM_UDP_PORTS;i++)
-    udpsocks[i] = make_udp_socket (i); 
-
-  if (-1 == (icmpsock = make_icmp_socket()))
-    return 1;
-
-  memset (&dst, 0, sizeof (dst));
-  dst.sin_family = AF_INET;
-  dst.sin_addr = dummy;
-  pos = 0;
-  tries = 0;
-
-  while (1)
-    {
-      tries++;
-
-      FD_ZERO (&rs);
-      FD_SET (icmpsock, &rs);
-      tv.tv_sec = 0;
-      tv.tv_usec = UDP_SEND_FREQUENCY_MS * 1000;
-      select (icmpsock + 1, &rs, NULL, NULL, &tv);
-      if (FD_ISSET (icmpsock, &rs))
-        process_icmp_response ();
-
-      if (udpsocks[pos] == -1)
-       {
-          udpsocks[pos] = make_udp_socket (pos);
-         continue;
-       }
-      if ( (0 == ((unsigned int)rand() % NUM_UDP_PORTS)) ||
-          (1 == first_round) )
-       dst.sin_port = htons (NAT_TRAV_PORT);
-      else
-       dst.sin_port = htons (make_port ());
-#if VERBOSE
-      fprintf (stderr,
-              "Sending UDP packet to `%s:%u'\n",
-              DUMMY_IP,
-              ntohs (dst.sin_port));
-
-#endif
-      first_round = 0;
-      if (-1 == sendto (udpsocks[pos],
-                        NULL, 0, 0,
-                        (struct sockaddr*) &dst, sizeof (dst)))
-        {
-          fprintf (stderr,
-                   "sendto failed: %s\n",
-                   strerror (errno));
-          close (udpsocks[pos]);
-          udpsocks[pos] = make_udp_socket (pos);
-        }
-      pos = (pos+1) % NUM_UDP_PORTS;
-    }
-  fprintf (stderr,
-          "Giving up after %u tries.\n",
-          tries);
-  return 3;
-}
-
-/* end of gnunet-nat-server-udp.c */