2 This file is part of GNUnet.
3 (C) 2012 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
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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21 * @file gnunet-dns2gns.c
22 * @brief DNS server that translates DNS requests to GNS
23 * @author Christian Grothoff
26 #include <gnunet_util_lib.h>
27 #include <gnunet_dnsparser_lib.h>
28 #include <gnunet_gns_service.h>
31 * Timeout for DNS requests.
33 #define TIMEOUT GNUNET_TIME_UNIT_MINUTES
36 * Data kept per request.
41 * Socket to use for sending the reply.
43 struct GNUNET_NETWORK_Handle *lsock;
46 * Destination address to use.
51 * Initially, this is the DNS request, it will then be
52 * converted to the DNS response.
54 struct GNUNET_DNSPARSER_Packet *packet;
57 * Our GNS request handle.
59 struct GNUNET_GNS_LookupRequest *lookup;
62 * Task run on timeout or shutdown to clean up without
65 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
68 * Number of bytes in 'addr'.
76 * Handle to GNS resolver.
78 struct GNUNET_GNS_Handle *gns;
81 * Listen socket for IPv4.
83 static struct GNUNET_NETWORK_Handle *listen_socket4;
86 * Listen socket for IPv6.
88 static struct GNUNET_NETWORK_Handle *listen_socket6;
91 * Task for IPv4 socket.
93 static GNUNET_SCHEDULER_TaskIdentifier t4;
96 * Task for IPv6 socket.
98 static GNUNET_SCHEDULER_TaskIdentifier t6;
102 * Task run on shutdown. Cleans up everything.
105 * @param tc scheduler context
108 do_shutdown (void *cls,
109 const struct GNUNET_SCHEDULER_TaskContext *tc)
111 if (GNUNET_SCHEDULER_NO_TASK != t4)
112 GNUNET_SCHEDULER_cancel (t4);
113 if (GNUNET_SCHEDULER_NO_TASK != t6)
114 GNUNET_SCHEDULER_cancel (t6);
115 if (NULL != listen_socket4)
117 GNUNET_NETWORK_socket_close (listen_socket4);
118 listen_socket4 = NULL;
120 if (NULL != listen_socket6)
122 GNUNET_NETWORK_socket_close (listen_socket6);
123 listen_socket6 = NULL;
125 GNUNET_GNS_disconnect (gns);
131 * Send the response for the given request and clean up.
133 * @param request context for the request.
136 send_response (struct Request *request)
142 GNUNET_DNSPARSER_pack (request->packet,
143 UINT16_MAX /* is this not too much? */,
147 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
148 _("Failed to pack DNS response into UDP packet!\n"));
153 GNUNET_NETWORK_socket_sendto (request->lsock,
157 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "sendto");
160 GNUNET_SCHEDULER_cancel (request->timeout_task);
161 GNUNET_DNSPARSER_free_packet (request->packet);
162 GNUNET_free (request);
167 * Task run on timeout. Cleans up request.
169 * @param cls 'struct Request' of the request to clean up
170 * @param tc scheduler context
173 do_timeout (void *cls,
174 const struct GNUNET_SCHEDULER_TaskContext *tc)
176 struct Request *request = cls;
178 if (NULL != request->packet)
179 GNUNET_DNSPARSER_free_packet (request->packet);
180 if (NULL != request->lookup)
181 GNUNET_GNS_cancel_lookup_request (request->lookup);
182 GNUNET_free (request);
187 * Iterator called on obtained result for a GNS
191 * @param rd_count number of records
192 * @param rd the records in reply
195 result_processor (void *cls,
197 const struct GNUNET_NAMESTORE_RecordData *rd)
199 struct Request *request = cls;
200 struct GNUNET_DNSPARSER_Packet *packet;
202 struct GNUNET_DNSPARSER_Record rec;
204 request->lookup = NULL;
205 packet = request->packet;
206 packet->flags.query_or_response = 1;
207 packet->flags.return_code = GNUNET_DNSPARSER_RETURN_CODE_NO_ERROR;
208 packet->flags.checking_disabled = 0;
209 packet->flags.authenticated_data = 1;
210 packet->flags.zero = 0;
211 packet->flags.recursion_available = 1;
212 packet->flags.message_truncated = 0;
213 packet->flags.authoritative_answer = 0;
214 packet->flags.opcode = GNUNET_DNSPARSER_OPCODE_STATUS; // ???
215 for (i=0;i<rd_count;i++)
217 switch (rd[i].record_type)
219 case GNUNET_DNSPARSER_TYPE_A:
220 GNUNET_assert (sizeof (struct in_addr) == rd[i].data_size);
221 rec.name = GNUNET_strdup (packet->queries[0].name);
222 rec.data.raw.data = GNUNET_malloc (sizeof (struct in_addr));
223 memcpy (rec.data.raw.data,
226 rec.data.raw.data_len = sizeof (struct in_addr);
227 GNUNET_array_append (packet->answers,
231 case GNUNET_DNSPARSER_TYPE_AAAA:
232 GNUNET_assert (sizeof (struct in6_addr) == rd[i].data_size);
233 rec.name = GNUNET_strdup ("foo"); // request->name
234 rec.data.raw.data = GNUNET_malloc (sizeof (struct in6_addr));
235 memcpy (rec.data.raw.data,
238 rec.data.raw.data_len = sizeof (struct in6_addr);
239 GNUNET_array_append (packet->answers,
243 case GNUNET_DNSPARSER_TYPE_CNAME:
244 GNUNET_break (0); // FIXME: CNAME is handled by the GNS resolver! We never return this unless explicitly requested!
251 send_response (request);
256 * Handle DNS request.
258 * @param lsock socket to use for sending the reply
259 * @param addr address to use for sending the reply
260 * @param addr_len number of bytes in addr
261 * @param udp_msg DNS request payload
262 * @param udp_msg_size number of bytes in udp_msg
265 handle_request (struct GNUNET_NETWORK_Handle *lsock,
271 struct Request *request;
272 struct GNUNET_DNSPARSER_Packet *packet;
275 enum GNUNET_GNS_RecordType type;
277 packet = GNUNET_DNSPARSER_parse (udp_msg, udp_msg_size);
280 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
281 _("Received malformed DNS request from %s\n"),
282 GNUNET_a2s (addr, addr_len));
285 if ( (0 != packet->flags.query_or_response) ||
286 (0 != packet->num_answers) ||
287 (0 != packet->num_authority_records) ||
288 (0 != packet->num_additional_records) )
290 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
291 _("Received malformed DNS request from %s\n"),
292 GNUNET_a2s (addr, addr_len));
293 GNUNET_DNSPARSER_free_packet (packet);
296 if ( (1 != packet->num_queries) )
298 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
299 _("Received unsupported DNS request from %s\n"),
300 GNUNET_a2s (addr, addr_len));
301 GNUNET_DNSPARSER_free_packet (packet);
304 request = GNUNET_malloc (sizeof (struct Request) + addr_len);
305 request->lsock = lsock;
306 request->packet = packet;
307 request->addr = &request[1];
308 request->addr_len = addr_len;
309 memcpy (&request[1], addr, addr_len);
310 request->timeout_task = GNUNET_SCHEDULER_add_delayed (TIMEOUT,
313 name = GNUNET_strdup (packet->queries[0].name);
314 name_len = strlen (name);
315 if ( (name_len > strlen (".zkey.eu")) &&
316 (0 == strcasecmp (".zkey.eu",
317 &name[name_len - strlen (".zkey.eu")])) )
319 //FIXME here check if the top label after zkey.eu is a hash and append
320 //correct TLD appropriately
321 name[name_len - strlen (".zkey.eu")] = '\0';
322 strcat (name, ".gnunet"); /* little hack, only works because
323 ".zkey.eu" is longer than ".gnunet" */
324 name_len = strlen (name);
326 if ( (name_len > strlen (".gnunet")) &&
327 (0 == strcasecmp (".gnunet",
328 &name[name_len - strlen (".gnunet")])) )
330 type = packet->queries[0].type;
331 request->lookup = GNUNET_GNS_lookup (gns,
341 /* FIXME: do traditional *DNS* lookup; note that
342 gnunet-service-dns already has code to do this;
343 factor into library to share! Why not use GNUNET_RESOLVER here?*/
351 * Task to read IPv4 DNS packets.
353 * @param cls the 'listen_socket4'
354 * @param tc scheduler context
357 read_dns4 (void *cls,
358 const struct GNUNET_SCHEDULER_TaskContext *tc)
360 struct sockaddr_in v4;
364 GNUNET_assert (listen_socket4 == cls);
365 t4 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
369 if (0 == (GNUNET_SCHEDULER_REASON_READ_READY & tc->reason))
370 return; /* shutdown? */
371 size = GNUNET_NETWORK_socket_recvfrom_amount (listen_socket4);
375 return; /* read error!? */
380 addrlen = sizeof (v4);
381 GNUNET_break (size ==
382 GNUNET_NETWORK_socket_recvfrom (listen_socket4,
385 (struct sockaddr *) &v4,
387 handle_request (listen_socket4, &v4, addrlen,
394 * Task to read IPv6 DNS packets.
396 * @param cls the 'listen_socket6'
397 * @param tc scheduler context
400 read_dns6 (void *cls,
401 const struct GNUNET_SCHEDULER_TaskContext *tc)
403 struct sockaddr_in6 v6;
407 GNUNET_assert (listen_socket6 == cls);
408 t6 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
412 if (0 == (GNUNET_SCHEDULER_REASON_READ_READY & tc->reason))
413 return; /* shutdown? */
414 size = GNUNET_NETWORK_socket_recvfrom_amount (listen_socket6);
418 return; /* read error!? */
423 addrlen = sizeof (v6);
424 GNUNET_break (size ==
425 GNUNET_NETWORK_socket_recvfrom (listen_socket6,
428 (struct sockaddr *) &v6,
430 handle_request (listen_socket6, &v6, addrlen,
437 * Main function that will be run.
440 * @param args remaining command-line arguments
441 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
442 * @param cfg configuration
445 run (void *cls, char *const *args, const char *cfgfile,
446 const struct GNUNET_CONFIGURATION_Handle *cfg)
448 gns = GNUNET_GNS_connect (cfg);
451 listen_socket4 = GNUNET_NETWORK_socket_create (PF_INET,
454 if (NULL != listen_socket4)
456 struct sockaddr_in v4;
458 memset (&v4, 0, sizeof (v4));
459 v4.sin_family = AF_INET;
460 #if HAVE_SOCKADDR_IN_SIN_LEN
461 v4.sin_len = sizeof (v4);
463 v4.sin_port = htons (53);
465 GNUNET_NETWORK_socket_bind (listen_socket4,
466 (struct sockaddr *) &v4,
469 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
470 GNUNET_NETWORK_socket_close (listen_socket4);
471 listen_socket4 = NULL;
474 listen_socket6 = GNUNET_NETWORK_socket_create (PF_INET6,
477 if (NULL != listen_socket6)
479 struct sockaddr_in6 v6;
481 memset (&v6, 0, sizeof (v6));
482 v6.sin6_family = AF_INET6;
483 #if HAVE_SOCKADDR_IN_SIN_LEN
484 v6.sin6_len = sizeof (v6);
486 v6.sin6_port = htons (53);
488 GNUNET_NETWORK_socket_bind (listen_socket6,
489 (struct sockaddr *) &v6,
492 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
493 GNUNET_NETWORK_socket_close (listen_socket6);
494 listen_socket6 = NULL;
497 if ( (NULL == listen_socket4) &&
498 (NULL == listen_socket6) )
500 if (NULL != listen_socket4)
501 t4 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
505 if (NULL != listen_socket6)
506 t6 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
511 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
517 * The main function for the fcfs daemon.
519 * @param argc number of arguments from the command line
520 * @param argv command line arguments
521 * @return 0 ok, 1 on error
527 static const struct GNUNET_GETOPT_CommandLineOption options[] = {
528 GNUNET_GETOPT_OPTION_END
532 if (GNUNET_OK != GNUNET_STRINGS_get_utf8_args (argc, argv,
535 GNUNET_log_setup ("gnunet-dns2gns", "WARNING", NULL);
538 GNUNET_PROGRAM_run (argc, argv, "gnunet-dns2gns",
539 _("GNUnet DNS-to-GNS proxy (a DNS server)"),
541 &run, NULL)) ? 0 : 1;
546 /* end of gnunet-dns2gns.c */