2 This file is part of GNUnet.
3 (C) 2011 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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22 * @file src/nat/gnunet-nat-server.c
23 * @brief Daemon to run on 'gnunet.org' to help test NAT traversal code
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_nat_lib.h"
29 #include "gnunet_protocols.h"
32 #define DEBUG_NAT GNUNET_NO
37 static struct GNUNET_SERVER_Handle *server;
42 static const struct GNUNET_CONFIGURATION_Handle *cfg;
46 * Try contacting the peer using autonomous
47 * NAT traveral method.
49 * @param dst_ipv4 IPv4 address to send the fake ICMP message
50 * @param dport destination port to include in ICMP message
51 * @param is_tcp mark for TCP (GNUNET_YES) or UDP (GNUNET_NO)
54 try_anat (uint32_t dst_ipv4, uint16_t dport, int is_tcp)
56 struct GNUNET_NAT_Handle *h;
57 struct sockaddr_in sa;
60 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
61 "Asking for connection reversal with %x and code %u\n",
62 (unsigned int) dst_ipv4, (unsigned int) dport);
64 h = GNUNET_NAT_register (cfg, is_tcp, dport, 0, NULL, NULL, NULL, NULL, NULL);
65 memset (&sa, 0, sizeof (sa));
66 sa.sin_family = AF_INET;
67 #if HAVE_SOCKADDR_IN_SIN_LEN
68 sa.sin_len = sizeof (sa);
70 sa.sin_addr.s_addr = dst_ipv4;
71 GNUNET_NAT_run_client (h, &sa);
72 GNUNET_NAT_unregister (h);
77 * Closure for 'tcp_send'.
84 struct GNUNET_NETWORK_Handle *s;
94 * Task called by the scheduler once we can do the TCP send
95 * (or once we failed to connect...).
97 * @param ctx the 'struct TcpContext'
98 * @param tc scheduler context
101 tcp_send (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
103 struct TcpContext *ctx = cls;
105 if ((NULL != tc->write_ready) &&
106 (GNUNET_NETWORK_fdset_isset (tc->write_ready, ctx->s)))
109 GNUNET_NETWORK_socket_send (ctx->s, &ctx->data, sizeof (ctx->data)))
112 GNUNET_log_strerror (GNUNET_ERROR_TYPE_DEBUG, "send");
115 GNUNET_NETWORK_socket_shutdown (ctx->s, SHUT_RDWR);
117 GNUNET_NETWORK_socket_close (ctx->s);
123 * Try to send 'data' to the
124 * IP 'dst_ipv4' at port 'dport' via TCP.
126 * @param dst_ivp4 target IP
127 * @param dport target port
128 * @param data data to send
131 try_send_tcp (uint32_t dst_ipv4, uint16_t dport, uint16_t data)
133 struct GNUNET_NETWORK_Handle *s;
134 struct sockaddr_in sa;
135 struct TcpContext *ctx;
137 s = GNUNET_NETWORK_socket_create (AF_INET, SOCK_STREAM, 0);
140 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "socket");
143 memset (&sa, 0, sizeof (sa));
144 sa.sin_family = AF_INET;
145 #if HAVE_SOCKADDR_IN_SIN_LEN
146 sa.sin_len = sizeof (sa);
148 sa.sin_addr.s_addr = dst_ipv4;
149 sa.sin_port = htons (dport);
151 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
152 "Sending TCP message to `%s'\n",
153 GNUNET_a2s ((struct sockaddr *) &sa, sizeof (sa)));
156 GNUNET_NETWORK_socket_connect (s,
157 (const struct sockaddr *) &sa,
158 sizeof (sa))) && (errno != EINPROGRESS))
160 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "connect");
161 GNUNET_NETWORK_socket_close (s);
164 ctx = GNUNET_malloc (sizeof (struct TcpContext));
167 GNUNET_SCHEDULER_add_write_net (GNUNET_TIME_UNIT_SECONDS, s, &tcp_send, ctx);
172 * Try to send 'data' to the
173 * IP 'dst_ipv4' at port 'dport' via UDP.
175 * @param dst_ivp4 target IP
176 * @param dport target port
177 * @param data data to send
180 try_send_udp (uint32_t dst_ipv4, uint16_t dport, uint16_t data)
182 struct GNUNET_NETWORK_Handle *s;
183 struct sockaddr_in sa;
185 s = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
188 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "socket");
191 memset (&sa, 0, sizeof (sa));
192 sa.sin_family = AF_INET;
193 #if HAVE_SOCKADDR_IN_SIN_LEN
194 sa.sin_len = sizeof (sa);
196 sa.sin_addr.s_addr = dst_ipv4;
197 sa.sin_port = htons (dport);
199 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
200 "Sending UDP packet to `%s'\n",
201 GNUNET_a2s ((struct sockaddr *) &sa, sizeof (sa)));
203 if (-1 == GNUNET_NETWORK_socket_sendto (s,
204 &data, sizeof (data),
205 (const struct sockaddr *) &sa,
207 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "sendto");
208 GNUNET_NETWORK_socket_close (s);
213 * We've received a request to probe a NAT
217 * @param client handle to client (we always close)
218 * @param msg message with details about what to test
222 struct GNUNET_SERVER_Client *client,
223 const struct GNUNET_MessageHeader *msg)
225 const struct GNUNET_NAT_TestMessage *tm;
229 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received test request\n");
231 tm = (const struct GNUNET_NAT_TestMessage *) msg;
232 dport = ntohs (tm->dport);
234 try_anat (tm->dst_ipv4, ntohs (tm->data), (int) ntohl (tm->is_tcp));
235 else if (GNUNET_YES == ntohl (tm->is_tcp))
236 try_send_tcp (tm->dst_ipv4, dport, tm->data);
238 try_send_udp (tm->dst_ipv4, dport, tm->data);
239 GNUNET_SERVER_receive_done (client, GNUNET_NO);
244 * Task run during shutdown.
247 * @param tc scheduler context
250 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
252 GNUNET_SERVER_destroy (server);
258 * Main function that will be run.
261 * @param args remaining command-line arguments
262 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
263 * @param c configuration
268 const char *cfgfile, const struct GNUNET_CONFIGURATION_Handle *c)
270 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
271 {&test, NULL, GNUNET_MESSAGE_TYPE_NAT_TEST,
272 sizeof (struct GNUNET_NAT_TestMessage)},
276 struct sockaddr_in in4;
277 struct sockaddr_in6 in6;
284 struct sockaddr *sa[] = {
285 (struct sockaddr *) &in4,
286 (struct sockaddr *) &in6,
291 if ((args[0] == NULL) ||
292 (1 != SSCANF (args[0], "%u", &port)) || (0 == port) || (65536 <= port))
296 ("Please pass valid port number as the first argument! (got `%s')\n"),
300 memset (&in4, 0, sizeof (in4));
301 memset (&in6, 0, sizeof (in6));
302 in4.sin_family = AF_INET;
303 in4.sin_port = htons ((uint16_t) port);
304 in6.sin6_family = AF_INET6;
305 in6.sin6_port = htons ((uint16_t) port);
306 #if HAVE_SOCKADDR_IN_SIN_LEN
307 in4.sin_len = sizeof (in4);
308 in6.sin6_len = sizeof (in6);
310 server = GNUNET_SERVER_create (NULL, NULL,
311 (struct sockaddr * const *) sa,
312 slen, GNUNET_TIME_UNIT_SECONDS, GNUNET_YES);
313 GNUNET_SERVER_add_handlers (server, handlers);
314 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
315 &shutdown_task, NULL);
320 * Main function of gnunet-nat-server.
322 * @param argc number of command-line arguments
323 * @param argv command line
324 * @return 0 on success, -1 on error
327 main (int argc, char *const argv[])
329 static const struct GNUNET_GETOPT_CommandLineOption options[] = {
330 GNUNET_GETOPT_OPTION_END
334 GNUNET_PROGRAM_run (argc, argv,
335 "gnunet-nat-server [options] PORT",
336 _("GNUnet NAT traversal test helper daemon"),
337 options, &run, NULL))
343 /* end of gnunet-nat-server.c */