GNUnet  0.10.x
gnunet-service-gns.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2011-2018 GNUnet e.V.
4 
5  GNUnet is free software: you can redistribute it and/or modify it
6  under the terms of the GNU Affero General Public License as published
7  by the Free Software Foundation, either version 3 of the License,
8  or (at your option) any later version.
9 
10  GNUnet is distributed in the hope that it will be useful, but
11  WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  Affero General Public License for more details.
14 
15  You should have received a copy of the GNU Affero General Public License
16  along with this program. If not, see <http://www.gnu.org/licenses/>.
17 
18  SPDX-License-Identifier: AGPL3.0-or-later
19  */
26 #include "platform.h"
27 #include "gnunet_util_lib.h"
28 #include "gnunet_dns_service.h"
29 #include "gnunet_dnsparser_lib.h"
30 #include "gnunet_dht_service.h"
32 #include "gnunet_gnsrecord_lib.h"
33 #include "gnunet_gns_service.h"
35 #include "gns.h"
38 #include "gnunet_protocols.h"
39 
40 
44 struct GnsClient;
45 
54 
59 
63  struct GnsClient *gc;
64 
69 
73  uint32_t request_id;
74 };
75 
76 
80 struct GnsClient {
85 
90 
95 
100 };
101 
102 
113 
119 
124 
128  char *tld;
129 };
130 
131 
136 
141 
145 static int v6_enabled;
146 
150 static int v4_enabled;
151 
156 
161 
166 
167 
175 int
176 GNS_find_tld(const char *tld_str,
178 {
179  if ('\0' == *tld_str)
180  return GNUNET_NO;
181  for (struct GNS_TopLevelDomain *tld = tld_head;
182  NULL != tld;
183  tld = tld->next)
184  {
185  if (0 == strcasecmp(tld_str,
186  tld->tld))
187  {
188  *pkey = tld->pkey;
189  return GNUNET_YES;
190  }
191  }
192  if (GNUNET_OK ==
193  GNUNET_GNSRECORD_zkey_to_pkey(tld_str + 1,
194  pkey))
195  return GNUNET_YES; /* TLD string *was* the public key */
196  return GNUNET_NO;
197 }
198 
199 
207 const char *
208 GNS_get_tld(const char *name)
209 {
210  const char *tld;
211 
212  tld = strrchr(name,
213  (unsigned char)'.');
214  if (NULL == tld)
215  tld = name;
216  else
217  tld++; /* skip the '.' */
218  return tld;
219 }
220 
221 
227 static void
228 shutdown_task(void *cls)
229 {
230  struct GNS_TopLevelDomain *tld;
231 
232  (void)cls;
234  "Shutting down!\n");
237  if (NULL != statistics)
238  {
239  GNUNET_STATISTICS_destroy(statistics,
240  GNUNET_NO);
241  statistics = NULL;
242  }
243  if (NULL != namecache_handle)
244  {
245  GNUNET_NAMECACHE_disconnect(namecache_handle);
246  namecache_handle = NULL;
247  }
248  if (NULL != dht_handle)
249  {
250  GNUNET_DHT_disconnect(dht_handle);
251  dht_handle = NULL;
252  }
253  while (NULL != (tld = tld_head))
254  {
256  tld_tail,
257  tld);
258  GNUNET_free(tld->tld);
259  GNUNET_free(tld);
260  }
261 }
262 
263 
271 static void
273  struct GNUNET_SERVICE_Client *client,
274  void *app_ctx)
275 {
276  struct ClientLookupHandle *clh;
277  struct GnsClient *gc = app_ctx;
278 
279  (void)cls;
281  "Client %p disconnected\n",
282  client);
283  while (NULL != (clh = gc->clh_head))
284  {
285  if (NULL != clh->lookup)
288  gc->clh_tail,
289  clh);
290  GNUNET_free(clh);
291  }
292  GNUNET_free(gc);
293 }
294 
295 
304 static void *
307  struct GNUNET_MQ_Handle *mq)
308 {
309  struct GnsClient *gc;
310 
311  (void)cls;
313  "Client %p connected\n",
314  client);
315  gc = GNUNET_new(struct GnsClient);
316  gc->client = client;
317  gc->mq = mq;
318  return gc;
319 }
320 
321 
329 static void
331  uint32_t rd_count,
332  const struct GNUNET_GNSRECORD_Data *rd)
333 {
334  struct ClientLookupHandle *clh = cls;
335  struct GnsClient *gc = clh->gc;
336  struct GNUNET_MQ_Envelope *env;
337  struct LookupResultMessage *rmsg;
338  ssize_t len;
339 
341  "Sending LOOKUP_RESULT message with %u results\n",
342  (unsigned int)rd_count);
343  len = GNUNET_GNSRECORD_records_get_size(rd_count,
344  rd);
345  if (len < 0)
346  {
347  GNUNET_break(0);
349  return;
350  }
351  if (len > UINT16_MAX - sizeof(*rmsg))
352  {
353  GNUNET_break(0);
355  return;
356  }
357  env = GNUNET_MQ_msg_extra(rmsg,
358  len,
360  rmsg->id = clh->request_id;
361  rmsg->rd_count = htonl(rd_count);
362  GNUNET_assert(len ==
364  rd,
365  len,
366  (char*)&rmsg[1]));
368  env);
370  gc->clh_tail,
371  clh);
372  GNUNET_free(clh);
373  GNUNET_STATISTICS_update(statistics,
374  "Completed lookups", 1,
375  GNUNET_NO);
376  GNUNET_STATISTICS_update(statistics,
377  "Records resolved",
378  rd_count,
379  GNUNET_NO);
380 }
381 
382 
390 static int
391 check_lookup(void *cls,
392  const struct LookupMessage *l_msg)
393 {
394  size_t nlen;
395 
396  (void)cls;
398  nlen = ntohs(l_msg->header.size) - sizeof(struct LookupMessage);
400  {
401  GNUNET_break(0);
402  return GNUNET_SYSERR;
403  }
404  return GNUNET_OK;
405 }
406 
407 
415 static void
416 handle_lookup(void *cls,
417  const struct LookupMessage *sh_msg)
418 {
419  struct GnsClient *gc = cls;
421  struct ClientLookupHandle *clh;
422  char *nameptr = name;
423  const char *utf_in;
424 
426  utf_in = (const char *)&sh_msg[1];
428  nameptr);
430  "Received LOOKUP `%s' message\n",
431  name);
432  clh = GNUNET_new(struct ClientLookupHandle);
434  gc->clh_tail,
435  clh);
436  clh->gc = gc;
437  clh->request_id = sh_msg->id;
438  if ((GNUNET_DNSPARSER_TYPE_A == ntohl(sh_msg->type)) &&
439  (GNUNET_OK != v4_enabled))
440  {
442  "LOOKUP: Query for A record but AF_INET not supported!");
444  0,
445  NULL);
446  return;
447  }
448  if ((GNUNET_DNSPARSER_TYPE_AAAA == ntohl(sh_msg->type)) &&
449  (GNUNET_OK != v6_enabled))
450  {
452  "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
454  0,
455  NULL);
456  return;
457  }
458  clh->lookup = GNS_resolver_lookup(&sh_msg->zone,
459  ntohl(sh_msg->type),
460  name,
461  (enum GNUNET_GNS_LocalOptions)ntohs(sh_msg->options),
462  &send_lookup_response, clh);
463  GNUNET_STATISTICS_update(statistics,
464  "Lookup attempts",
465  1, GNUNET_NO);
466 }
467 
468 
477 static void
479  const char *section,
480  const char *option,
481  const char *value)
482 {
484  struct GNS_TopLevelDomain *tld;
485 
486  (void)cls;
487  (void)section;
488  if (option[0] != '.')
489  return;
490  if (GNUNET_OK !=
492  strlen(value),
493  &pk,
494  sizeof(pk)))
495  {
497  section,
498  option,
499  _("Properly base32-encoded public key required"));
500  return;
501  }
502  tld = GNUNET_new(struct GNS_TopLevelDomain);
503  tld->tld = GNUNET_strdup(&option[1]);
504  tld->pkey = pk;
506  tld_tail,
507  tld);
508 }
509 
510 
518 static void
519 run(void *cls,
520  const struct GNUNET_CONFIGURATION_Handle *c,
522 {
523  unsigned long long max_parallel_bg_queries = 16;
524 
526  "gns",
528  NULL);
531  namecache_handle = GNUNET_NAMECACHE_connect(c);
532  if (NULL == namecache_handle)
533  {
535  _("Failed to connect to the namecache!\n"));
537  return;
538  }
539  if (GNUNET_OK ==
541  "gns",
542  "MAX_PARALLEL_BACKGROUND_QUERIES",
543  &max_parallel_bg_queries))
544  {
546  "Number of allowed parallel background queries: %llu\n",
547  max_parallel_bg_queries);
548  }
549  dht_handle = GNUNET_DHT_connect(c,
550  (unsigned int)max_parallel_bg_queries);
551  if (NULL == dht_handle)
552  {
554  _("Could not connect to DHT!\n"));
556  NULL);
557  return;
558  }
559  GNS_resolver_init(namecache_handle,
560  dht_handle,
561  c,
562  max_parallel_bg_queries);
563  if ((GNUNET_YES ==
565  "gns",
566  "INTERCEPT_DNS")) &&
567  (GNUNET_SYSERR ==
569  {
570  GNUNET_break(0);
572  NULL);
573  return;
574  }
575  statistics = GNUNET_STATISTICS_create("gns",
576  c);
578  NULL);
579 }
580 
581 
586  ("gns",
588  &run,
591  NULL,
594  struct LookupMessage,
595  NULL),
597 
598 
599 /* end of gnunet-service-gns.c */
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
static void run(void *cls, const struct GNUNET_CONFIGURATION_Handle *c, struct GNUNET_SERVICE_Handle *service)
Process GNS requests.
Message from client to GNS service to lookup records.
Definition: gns.h:36
struct GNUNET_NAMECACHE_Handle * GNUNET_NAMECACHE_connect(const struct GNUNET_CONFIGURATION_Handle *cfg)
Connect to the namecache service.
Message from GNS service to client: new results.
Definition: gns.h:75
uint32_t id
Unique identifier for this request (for key collisions).
Definition: gns.h:45
static struct GNUNET_SERVICE_Handle * service
Handle to our service instance.
GNUNET_NETWORK_STRUCT_END ssize_t GNUNET_GNSRECORD_records_get_size(unsigned int rd_count, const struct GNUNET_GNSRECORD_Data *rd)
Calculate how many bytes we will need to serialize the given records.
struct GNS_TopLevelDomain * next
Kept in a DLL, as there are unlikely enough of these to warrant a hash map.
static struct GNUNET_CRYPTO_EddsaPrivateKey * pk
Private key of this peer.
void GNS_resolver_lookup_cancel(struct GNS_ResolverHandle *rh)
Cancel active resolution (i.e.
struct ClientLookupHandle * prev
We keep these in a DLL.
int GNUNET_CONFIGURATION_get_value_number(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, unsigned long long *number)
Get a configuration value that should be a number.
static struct GNS_TopLevelDomain * tld_head
Head of DLL of TLDs we map to GNS zones.
static char * pkey
Public key of the zone to look in, in ASCII.
uint32_t rd_count
The number of records contained in response.
Definition: gns.h:89
void GNUNET_CONFIGURATION_iterate_section_values(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, GNUNET_CONFIGURATION_Iterator iter, void *iter_cls)
Iterate over values of a section in the configuration.
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
struct GNS_TopLevelDomain * prev
Kept in a DLL, as there are unlikely enough of these to warrant a hash map.
Handle to a service.
Definition: service.c:114
struct GNUNET_CRYPTO_EcdsaPublicKey zone
Zone that is to be used for lookup.
Definition: gns.h:50
struct GNUNET_MQ_Handle * GNUNET_SERVICE_client_get_mq(struct GNUNET_SERVICE_Client *c)
Obtain the message queue of c.
Definition: service.c:2424
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_shutdown(GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run on shutdown, that is when a CTRL-C signal is received, or when GNUNET_SCHEDULER_shutdown() is being invoked.
Definition: scheduler.c:1284
ssize_t GNUNET_GNSRECORD_records_serialize(unsigned int rd_count, const struct GNUNET_GNSRECORD_Data *rd, size_t dest_size, char *dest)
Serialize the given records to the given destination buffer.
const char * GNS_get_tld(const char *name)
Obtain the TLD of the given name.
#define GNUNET_MESSAGE_TYPE_GNS_LOOKUP
Client would like to resolve a name.
struct GNUNET_STATISTICS_Handle * GNUNET_STATISTICS_create(const char *subsystem, const struct GNUNET_CONFIGURATION_Handle *cfg)
Get handle for the statistics service.
static void client_disconnect_cb(void *cls, struct GNUNET_SERVICE_Client *client, void *app_ctx)
Called whenever a client is disconnected.
struct GNUNET_CRYPTO_EcdsaPublicKey pkey
Public key associated with the tld.
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
int GNUNET_GNSRECORD_zkey_to_pkey(const char *zkey, struct GNUNET_CRYPTO_EcdsaPublicKey *pkey)
Convert an absolute domain name to the respective public key.
#define GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT
Service response to name resolution request from client.
GNUNET_GNS_LocalOptions
Options for the GNS lookup.
struct ClientLookupHandle * next
We keep these in a DLL.
#define GNUNET_NO
Definition: gnunet_common.h:78
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
int32_t type
the type of record to look up
Definition: gns.h:66
#define GNUNET_new(type)
Allocate a struct or union of the given type.
void GNUNET_log_config_invalid(enum GNUNET_ErrorType kind, const char *section, const char *option, const char *required)
Log error message about invalid configuration option value.
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format...
void GNUNET_STATISTICS_destroy(struct GNUNET_STATISTICS_Handle *h, int sync_first)
Destroy a handle (free all state associated with it).
void GNUNET_STATISTICS_update(struct GNUNET_STATISTICS_Handle *handle, const char *name, int64_t delta, int make_persistent)
Set statistic value for the peer.
void GNUNET_SCHEDULER_shutdown(void)
Request the shutdown of a scheduler.
Definition: scheduler.c:517
Handle for the service.
static int v6_enabled
GNUNET_YES if ipv6 is supported
#define GNUNET_strdup(a)
Wrapper around GNUNET_xstrdup_.
IPC messages between GNS API and GNS service.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
int GNS_interceptor_init(const struct GNUNET_CONFIGURATION_Handle *c)
Initialized the interceptor.
Handle to a currenty pending resolution.
Connection to the DHT service.
Definition: dht_api.c:198
struct GNUNET_MQ_Handle * mq
The MQ.
#define _(String)
GNU gettext support macro.
Definition: platform.h:181
static char * section
Name of the section.
Definition: gnunet-config.c:33
static struct GNUNET_STATISTICS_Handle * statistics
Handle to the statistics service.
Handle to a client that is connected to a service.
Definition: service.c:246
static int check_lookup(void *cls, const struct LookupMessage *l_msg)
Checks a GNUNET_MESSAGE_TYPE_GNS_LOOKUP message.
struct GNUNET_SERVICE_Client * client
The client.
uint32_t request_id
request id
struct GNUNET_MessageHeader header
Header of type GNUNET_MESSAGE_TYPE_GNS_LOOKUP.
Definition: gns.h:40
#define GNUNET_MQ_msg_extra(mvar, esize, type)
Allocate an envelope, with extra space allocated after the space needed by the message struct...
Definition: gnunet_mq_lib.h:52
#define GNUNET_DNSPARSER_MAX_NAME_LENGTH
Maximum length of a name in DNS.
#define GNUNET_MQ_check_zero_termination(m)
Insert code for a "check_" function that verifies that a given variable-length message received over ...
static void shutdown_task(void *cls)
Task run during shutdown.
static char * value
Value of the record to add/remove.
uint32_t id
Unique identifier for this request (for key collisions).
Definition: gns.h:84
static struct GNUNET_DHT_Handle * dht_handle
Our handle to the DHT.
#define GNUNET_MQ_hd_var_size(name, code, str, ctx)
static void handle_lookup(void *cls, const struct LookupMessage *sh_msg)
Handle lookup requests from client.
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_now(GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run as soon as possible.
Definition: scheduler.c:1264
static struct GNUNET_NAMECACHE_Handle * namecache_handle
Our handle to the namecache service.
static struct GNS_TopLevelDomain * tld_tail
Tail of DLL of TLDs we map to GNS zones.
static char * option
Name of the option.
Definition: gnunet-config.c:38
static void * client_connect_cb(void *cls, struct GNUNET_SERVICE_Client *client, struct GNUNET_MQ_Handle *mq)
Add a client to our list of active clients.
void GNS_interceptor_done()
Disconnect from interceptor.
struct GnsClient * gc
Client handle.
void GNS_resolver_done()
Shutdown resolver.
static int v4_enabled
GNUNET_YES if ipv4 is supported
struct GNS_ResolverHandle * lookup
Active handle for the lookup.
void GNUNET_SERVICE_client_drop(struct GNUNET_SERVICE_Client *c)
Ask the server to disconnect from the given client.
Definition: service.c:2315
Handle to a lookup operation from client via API.
int16_t options
Local options for where to look for results (an enum GNUNET_GNS_LocalOptions in NBO).
Definition: gns.h:56
GNUnet GNS service.
#define GNUNET_SYSERR
Definition: gnunet_common.h:76
struct GNUNET_DHT_Handle * GNUNET_DHT_connect(const struct GNUNET_CONFIGURATION_Handle *cfg, unsigned int ht_len)
Initialize the connection with the DHT service.
Definition: dht_api.c:885
const char * name
void GNUNET_DHT_disconnect(struct GNUNET_DHT_Handle *handle)
Shutdown connection with the DHT service.
Definition: dht_api.c:913
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
struct GNS_ResolverHandle * GNS_resolver_lookup(const struct GNUNET_CRYPTO_EcdsaPublicKey *zone, uint32_t record_type, const char *name, enum GNUNET_GNS_LocalOptions options, GNS_ResultProcessor proc, void *proc_cls)
Lookup of a record in a specific zone calls lookup result processor on result.
void GNS_resolver_init(struct GNUNET_NAMECACHE_Handle *nc, struct GNUNET_DHT_Handle *dht, const struct GNUNET_CONFIGURATION_Handle *c, unsigned long long max_bg_queries)
Initialize the resolver.
static void read_service_conf(void *cls, const char *section, const char *option, const char *value)
Reads the configuration and populates TLDs.
Handle to a message queue.
Definition: mq.c:84
Information we track per connected client.
#define GNUNET_DNSPARSER_TYPE_AAAA
configuration data
Definition: configuration.c:83
Representation of a TLD, mapping the respective TLD string (i.e.
int GNS_find_tld(const char *tld_str, struct GNUNET_CRYPTO_EcdsaPublicKey *pkey)
Find GNS zone belonging to TLD tld.
struct ClientLookupHandle * clh_head
Head of the DLL.
Public ECC key (always for Curve25519) encoded in a format suitable for network transmission and ECDS...
Connection to the NAMECACHE service.
Definition: namecache_api.c:93
struct GNUNET_MQ_Handle * mq
Definition: 003.c:5
#define GNUNET_log(kind,...)
static void send_lookup_response(void *cls, uint32_t rd_count, const struct GNUNET_GNSRECORD_Data *rd)
Reply to client with the result from our lookup.
char * tld
Top-level domain as a string, including leading ".".
void GNUNET_NAMECACHE_disconnect(struct GNUNET_NAMECACHE_Handle *h)
Disconnect from the namecache service (and free associated resources).
#define GNUNET_YES
Definition: gnunet_common.h:77
void GNUNET_MQ_send(struct GNUNET_MQ_Handle *mq, struct GNUNET_MQ_Envelope *ev)
Send a message with the given message queue.
Definition: mq.c:351
GNUNET_SERVICE_MAIN("gns", GNUNET_SERVICE_OPTION_NONE, &run, &client_connect_cb, &client_disconnect_cb, NULL, GNUNET_MQ_hd_var_size(lookup, GNUNET_MESSAGE_TYPE_GNS_LOOKUP, struct LookupMessage, NULL), GNUNET_MQ_handler_end())
Define "main" method using service macro.
int GNUNET_CONFIGURATION_get_value_yesno(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option)
Get a configuration value that should be in a set of "YES" or "NO".
#define GNUNET_DNSPARSER_TYPE_A
void GNUNET_SERVICE_client_continue(struct GNUNET_SERVICE_Client *c)
Continue receiving further messages from the given client.
Definition: service.c:2234
#define GNUNET_MQ_handler_end()
End-marker for the handlers array.
int GNUNET_STRINGS_string_to_data(const char *enc, size_t enclen, void *out, size_t out_size)
Convert CrockfordBase32 encoding back to data.
Definition: strings.c:953
int GNUNET_NETWORK_test_pf(int pf)
Test if the given protocol family is supported by this system.
Definition: network.c:78
struct ClientLookupHandle * clh_tail
Tail of the DLL.
#define GNUNET_free(ptr)
Wrapper around free.
void GNUNET_STRINGS_utf8_tolower(const char *input, char *output)
Convert the utf-8 input string to lower case.
Definition: strings.c:552
uint16_t len
length of data (which is always a uint32_t, but presumably this can be used to specify that fewer byt...