--- /dev/null
+/*
+ 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/client-test.c
+ * @brief Test for NAT traversal using ICMP method.
+ * @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>
+
+/**
+ * How often do we send our UDP messages to keep ports open (and to
+ * try to connect, of course). Use small value since we are the
+ * initiator and should hence be rather aggressive.
+ */
+#define UDP_SEND_FREQUENCY_MS 5
+
+/**
+ * Port we always try to use.
+ */
+#define NAT_TRAV_PORT 22223
+
+/**
+ * Number of UDP ports to keep open at the same time (typically >= 256).
+ * Should be less than FD_SETSIZE.
+ */
+#define NUM_UDP_PORTS 1000
+
+/**
+ * How often do we retry to open and bind a UDP socket before giving up?
+ */
+#define MAX_BIND_TRIES 10
+
+/**
+ * How often do we try at most? We expect to need (for the worst kind
+ * of NAT) on average 64512 / 512 = 126 attempts to have the right
+ * destination port and we then need to also (in the worst case) have
+ * the right source port (so 126 * 64512 = 8128512 packets on
+ * average!). That's obviously a bit much, so we give up earlier. The
+ * given value corresponds to about 1 minute of runtime (for a send
+ * frequency of one packet per ms).
+ *
+ * NOW: if the *server* would listen for Linux-generated ICMP
+ * "Destination unreachables" we *might* increase our chances since
+ * maybe the firewall has some older/other UDP rules (this was
+ * the case during testing for me), but obviously that would mean
+ * more SUID'ed code. Yuck.
+ */
+#define MAX_TRIES 62500
+
+#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);
+}
+
+
+/**
+ * create a fresh udp socket bound to a random local port,
+ * or, if the argument is zero, to the NAT_TRAV_PORT.
+ *
+ * @param i counter
+ * @return -1 on error
+ */
+static int
+make_udp_socket (int i)
+{
+ 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;
+ if (i == 0)
+ src.sin_port = htons (NAT_TRAV_PORT);
+ else
+ src.sin_port = htons (make_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;
+}
+
+
+
+
+int
+main (int argc, char *const *argv)
+{
+ int udpsocks[NUM_UDP_PORTS];
+ char command[512];
+ struct in_addr external;
+ struct in_addr target;
+ int ret;
+ unsigned int pos;
+ int i;
+ int max;
+ struct sockaddr_in dst;
+ struct sockaddr_in src;
+ int first_round = 1;
+ char dummybuf[65536];
+ unsigned int tries;
+ struct timeval tv;
+ socklen_t slen;
+ fd_set rs;
+
+ if (argc != 3)
+ {
+ fprintf (stderr,
+ "This program must be started with our IP and the targets external IP as arguments.\n");
+ return 1;
+ }
+ 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;
+ }
+ snprintf (command,
+ sizeof (command),
+ "gnunet-nat-client %s %s",
+ argv[1],
+ argv[2]);
+ if (0 != (ret = system (command)))
+ {
+ if (ret == -1)
+ fprintf (stderr,
+ "Error running `%s': %s\n",
+ command,
+ strerror (errno));
+ return 1;
+ }
+ fprintf (stderr,
+ "Trying to connect to `%s'\n",
+ argv[2]);
+ srand (time(NULL));
+ for (i=0;i<NUM_UDP_PORTS;i++)
+ udpsocks[i] = make_udp_socket (i);
+ memset (&dst, 0, sizeof (dst));
+ dst.sin_family = AF_INET;
+ dst.sin_addr = target;
+ pos = 0;
+ tries = 0;
+ while (MAX_TRIES > tries++)
+ {
+ FD_ZERO (&rs);
+ for (i=0;i<NUM_UDP_PORTS;i++)
+ {
+ if (udpsocks[i] != -1)
+ FD_SET (udpsocks[i], &rs);
+ if (udpsocks[i] > max)
+ max = udpsocks[i];
+ }
+ tv.tv_sec = 0;
+ tv.tv_usec = UDP_SEND_FREQUENCY_MS * 1000;
+ select (max + 1, &rs, NULL, NULL, &tv);
+ for (i=0;i<NUM_UDP_PORTS;i++)
+ {
+ if (udpsocks[i] == -1)
+ continue;
+ if (! FD_ISSET (udpsocks[i], &rs))
+ continue;
+ slen = sizeof (src);
+ recvfrom (udpsocks[i],
+ dummybuf, sizeof (dummybuf), 0,
+ (struct sockaddr*) &src,
+ &slen);
+ if (slen != sizeof (src))
+ {
+ fprintf (stderr,
+ "Unexpected size of address.\n");
+ continue;
+ }
+ if (0 != memcmp (&src.sin_addr,
+ &target,
+ sizeof (external)))
+ {
+ fprintf (stderr,
+ "Unexpected sender IP\n");
+ continue;
+ }
+ /* discovered port! */
+ fprintf (stdout,
+ "%s:%u\n",
+ argv[2],
+ ntohs (src.sin_port));
+ dst.sin_port = src.sin_port;
+ if (-1 == sendto (udpsocks[i],
+ NULL, 0, 0,
+ (struct sockaddr*) &dst, sizeof (dst)))
+ {
+ fprintf (stderr,
+ "sendto failed: %s\n",
+ strerror (errno));
+ return 2; /* oops */
+ }
+ /* success! */
+ fprintf (stderr,
+ "Succeeded after %u packets.\n",
+ tries);
+ return 0;
+ }
+ 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 ());
+ fprintf (stderr,
+ "Sending UDP packet to `%s:%u'\n",
+ argv[2],
+ ntohs (dst.sin_port));
+ 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 client-test.c */
--- /dev/null
+/*
+ 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/server-test.c
+ * @brief Test for NAT traversal using ICMP method.
+ * @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>
+
+
+
+/**
+ * How often do we send our UDP messages to keep ports open (and to
+ * try to connect, of course). Assuming the NAT closes UDP ports
+ * after 60s, we need at least about 100ms here for 512 ports;
+ * however, we should open the ports quickly (and we don't yet
+ * differentiate between the first round and later rounds), so we pick
+ * a much lower value here for now.
+ */
+#define UDP_SEND_FREQUENCY_MS 50
+
+/**
+ * Port we always try to use.
+ */
+#define NAT_TRAV_PORT 22225
+
+/**
+ * Number of UDP ports to keep open at the same time (typically >= 256).
+ * Should be less than FD_SETSIZE.
+ */
+#define NUM_UDP_PORTS 1000
+
+/**
+ * How often do we retry to open and bind a UDP socket before giving up?
+ */
+#define MAX_BIND_TRIES 10
+
+/**
+ * How long do we try at most? We expect the other side to give
+ * up after about one minute for now.
+ */
+#define MAX_DURATION 60000
+
+#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);
+}
+
+
+/**
+ * create a fresh udp socket bound to a random local port,
+ * or, if the argument is zero, to the NAT_TRAV_PORT.
+ *
+ * @param i counter
+ * @return -1 on error
+ */
+static int
+make_udp_socket (int i)
+{
+ 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;
+ if (i == 0)
+ src.sin_port = htons (NAT_TRAV_PORT);
+ else
+ src.sin_port = htons (make_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;
+}
+
+
+int
+main (int argc, char *const *argv)
+{
+ int udpsocks[NUM_UDP_PORTS];
+ char command[512];
+ struct in_addr external;
+ struct in_addr target;
+ int ret;
+ unsigned int pos;
+ int i;
+ int max;
+ struct sockaddr_in dst;
+ struct sockaddr_in src;
+ int first_round = 1;
+ char dummybuf[65536];
+ unsigned int tries;
+ struct timeval tv;
+ socklen_t slen;
+ fd_set rs;
+ time_t stime;
+
+ if (argc != 3)
+ {
+ fprintf (stderr,
+ "This program must be started with our IP and the targets external IP as arguments.\n");
+ return 1;
+ }
+ 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;
+ }
+ fprintf (stderr,
+ "Trying to connect to %s\n",
+ argv[2]);
+ srand (stime = time(NULL));
+ for (i=0;i<NUM_UDP_PORTS;i++)
+ udpsocks[i] = make_udp_socket (i);
+ memset (&dst, 0, sizeof (dst));
+ dst.sin_family = AF_INET;
+ dst.sin_addr = target;
+ pos = 0;
+ tries = 0;
+ while (stime + MAX_DURATION >= time (NULL))
+ {
+ tries++;
+ FD_ZERO (&rs);
+ for (i=0;i<NUM_UDP_PORTS;i++)
+ {
+ if (udpsocks[i] != -1)
+ FD_SET (udpsocks[i], &rs);
+ if (udpsocks[i] > max)
+ max = udpsocks[i];
+ }
+ tv.tv_sec = 0;
+ tv.tv_usec = UDP_SEND_FREQUENCY_MS * 1000;
+ select (max + 1, &rs, NULL, NULL, &tv);
+ for (i=0;i<NUM_UDP_PORTS;i++)
+ {
+ if (udpsocks[i] == -1)
+ continue;
+ if (! FD_ISSET (udpsocks[i], &rs))
+ continue;
+ slen = sizeof (src);
+ recvfrom (udpsocks[i],
+ dummybuf, sizeof (dummybuf), 0,
+ (struct sockaddr*) &src,
+ &slen);
+ if (slen != sizeof (src))
+ {
+ fprintf (stderr,
+ "Unexpected size of address.\n");
+ continue;
+ }
+ if (0 != memcmp (&src.sin_addr,
+ &target,
+ sizeof (external)))
+ {
+ fprintf (stderr,
+ "Unexpected sender IP\n");
+ continue;
+ }
+ /* discovered port! */
+ fprintf (stdout,
+ "%s:%u\n",
+ argv[2],
+ ntohs (src.sin_port));
+ dst.sin_port = src.sin_port;
+ if (-1 == sendto (udpsocks[i],
+ NULL, 0, 0,
+ (struct sockaddr*) &dst, sizeof (dst)))
+ {
+ fprintf (stderr,
+ "sendto failed: %s\n",
+ strerror (errno));
+ return 2; /* oops */
+ }
+ /* success! */
+ fprintf (stderr,
+ "Succeeded after %u packets.\n",
+ tries);
+ return 0;
+ }
+ 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 ());
+ fprintf (stderr,
+ "Sending UDP packet to `%s:%u'\n",
+ argv[2],
+ ntohs (dst.sin_port));
+ 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 server-test.c */
projects / oweals / gnunet.git / commitdiff