GNUnet  0.19.3
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_dht_service.h"
31 #include "gnunet_gnsrecord_lib.h"
32 #include "gnunet_gns_service.h"
34 #include "gns.h"
37 #include "gnunet_protocols.h"
38 
39 
43 struct GnsClient;
44 
49 {
54 
59 
63  struct GnsClient *gc;
64 
69 
73  uint32_t request_id;
74 };
75 
76 
80 struct GnsClient
81 {
86 
91 
96 
101 };
102 
103 
109 {
115 
121 
126 
130  char *tld;
131 };
132 
133 
138 
143 
147 static int v6_enabled;
148 
152 static int v4_enabled;
153 
158 
163 
168 
169 
177 int
178 GNS_find_tld (const char *tld_str,
180 {
181  if ('\0' == *tld_str)
182  return GNUNET_NO;
183  for (struct GNS_TopLevelDomain *tld = tld_head;
184  NULL != tld;
185  tld = tld->next)
186  {
187  if (0 == strcasecmp (tld_str,
188  tld->tld))
189  {
190  *pkey = tld->pkey;
191  return GNUNET_YES;
192  }
193  }
194  if (GNUNET_OK ==
195  GNUNET_GNSRECORD_zkey_to_pkey (tld_str + 1,
196  pkey))
197  return GNUNET_YES; /* TLD string *was* the public key */
198  return GNUNET_NO;
199 }
200 
201 
209 const char *
210 GNS_get_tld (const char *name)
211 {
212  const char *tld;
213 
214  tld = strrchr (name,
215  (unsigned char) '.');
216  if (NULL == tld)
217  tld = name;
218  else
219  tld++; /* skip the '.' */
220  return tld;
221 }
222 
223 
229 static void
230 shutdown_task (void *cls)
231 {
232  struct GNS_TopLevelDomain *tld;
233 
234  (void) cls;
236  "Shutting down!\n");
239  if (NULL != statistics)
240  {
242  GNUNET_NO);
243  statistics = NULL;
244  }
245  if (NULL != namecache_handle)
246  {
248  namecache_handle = NULL;
249  }
250  if (NULL != dht_handle)
251  {
253  dht_handle = NULL;
254  }
255  while (NULL != (tld = tld_head))
256  {
258  tld_tail,
259  tld);
260  GNUNET_free (tld->tld);
261  GNUNET_free (tld);
262  }
263 }
264 
265 
273 static void
275  struct GNUNET_SERVICE_Client *client,
276  void *app_ctx)
277 {
278  struct ClientLookupHandle *clh;
279  struct GnsClient *gc = app_ctx;
280 
281  (void) cls;
283  "Client %p disconnected\n",
284  client);
285  while (NULL != (clh = gc->clh_head))
286  {
287  if (NULL != clh->lookup)
290  gc->clh_tail,
291  clh);
292  GNUNET_free (clh);
293  }
294  GNUNET_free (gc);
295 }
296 
297 
306 static void *
307 client_connect_cb (void *cls,
309  struct GNUNET_MQ_Handle *mq)
310 {
311  struct GnsClient *gc;
312 
313  (void) cls;
315  "Client %p connected\n",
316  client);
317  gc = GNUNET_new (struct GnsClient);
318  gc->client = client;
319  gc->mq = mq;
320  return gc;
321 }
322 
323 
331 static void
333  uint32_t rd_count,
334  const struct GNUNET_GNSRECORD_Data *rd)
335 {
336  struct ClientLookupHandle *clh = cls;
337  struct GnsClient *gc = clh->gc;
338  struct GNUNET_MQ_Envelope *env;
339  struct LookupResultMessage *rmsg;
340  ssize_t len;
341 
343  "Sending LOOKUP_RESULT message with %u results\n",
344  (unsigned int) rd_count);
346  rd);
347  if (len < 0)
348  {
349  GNUNET_break (0);
351  return;
352  }
353  if (len > UINT16_MAX - sizeof(*rmsg))
354  {
355  GNUNET_break (0);
357  return;
358  }
359  env = GNUNET_MQ_msg_extra (rmsg,
360  len,
362  rmsg->id = clh->request_id;
363  rmsg->rd_count = htonl (rd_count);
364  GNUNET_assert (len ==
366  rd,
367  len,
368  (char *) &rmsg[1]));
370  env);
372  gc->clh_tail,
373  clh);
374  GNUNET_free (clh);
376  "Completed lookups", 1,
377  GNUNET_NO);
379  "Records resolved",
380  rd_count,
381  GNUNET_NO);
382 }
383 
384 
392 static int
393 check_lookup (void *cls,
394  const struct LookupMessage *l_msg)
395 {
396  size_t nlen;
397  size_t klen;
398 
399  (void) cls;
400  klen = ntohl (l_msg->key_len);
401  nlen = ntohs (l_msg->header.size) - sizeof(struct LookupMessage) - klen;
403  {
404  GNUNET_break (0);
405  return GNUNET_SYSERR;
406  }
407  return GNUNET_OK;
408 }
409 
410 
417 static void
418 handle_lookup (void *cls,
419  const struct LookupMessage *sh_msg)
420 {
421  struct GnsClient *gc = cls;
422  struct ClientLookupHandle *clh;
424  const char *name;
425  size_t key_len;
426  size_t read;
427 
429  key_len = ntohl (sh_msg->key_len);
430  clh = GNUNET_new (struct ClientLookupHandle);
432  gc->clh_tail,
433  clh);
434  clh->gc = gc;
435  clh->request_id = sh_msg->id;
436  if ((GNUNET_SYSERR ==
438  key_len,
439  &zone,
440  &read)) ||
441  (read != key_len))
442  {
444  "LOOKUP: Failed to read zone key!");
446  0,
447  NULL);
448  return;
449  }
450  name = (const char *) &sh_msg[1] + key_len;
452  "Received LOOKUP `%s' message\n",
453  name);
454  if ((GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
455  (GNUNET_OK != v4_enabled))
456  {
458  "LOOKUP: Query for A record but AF_INET not supported!");
460  0,
461  NULL);
462  return;
463  }
464  if ((GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
465  (GNUNET_OK != v6_enabled))
466  {
468  "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
470  0,
471  NULL);
472  return;
473  }
475  ntohl (sh_msg->type),
476  name,
477  (enum GNUNET_GNS_LocalOptions) ntohs (
478  sh_msg->options),
479  ntohs (sh_msg->recursion_depth_limit),
480  &send_lookup_response, clh);
482  "Lookup attempts",
483  1, GNUNET_NO);
484 }
485 
486 
495 static void
496 read_service_conf (void *cls,
497  const char *section,
498  const char *option,
499  const char *value)
500 {
502  struct GNS_TopLevelDomain *tld;
503 
504  (void) cls;
505  (void) section;
506  if (option[0] != '.')
507  return;
508  if (GNUNET_OK !=
510  strlen (value),
511  &pk,
512  sizeof(pk)))
513  {
515  section,
516  option,
517  _ (
518  "Properly base32-encoded public key required"));
519  return;
520  }
521  tld = GNUNET_new (struct GNS_TopLevelDomain);
522  tld->tld = GNUNET_strdup (&option[1]);
523  tld->pkey = pk;
525  tld_tail,
526  tld);
527 }
528 
529 
537 static void
538 run (void *cls,
539  const struct GNUNET_CONFIGURATION_Handle *c,
541 {
542  unsigned long long max_parallel_bg_queries = 16;
543 
545  "gns",
547  NULL);
548  v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
551  if (NULL == namecache_handle)
552  {
554  _ ("Failed to connect to the namecache!\n"));
556  return;
557  }
558  if (GNUNET_OK ==
560  "gns",
561  "MAX_PARALLEL_BACKGROUND_QUERIES",
562  &max_parallel_bg_queries))
563  {
565  "Number of allowed parallel background queries: %llu\n",
566  max_parallel_bg_queries);
567  }
569  (unsigned int) max_parallel_bg_queries);
570  if (NULL == dht_handle)
571  {
573  _ ("Could not connect to DHT!\n"));
575  NULL);
576  return;
577  }
579  dht_handle,
580  c,
581  max_parallel_bg_queries);
582  if ((GNUNET_YES ==
584  "gns",
585  "INTERCEPT_DNS")) &&
586  (GNUNET_SYSERR ==
588  {
589  GNUNET_break (0);
591  NULL);
592  return;
593  }
595  c);
597  NULL);
598 }
599 
600 
605  ("gns",
607  &run,
610  NULL,
611  GNUNET_MQ_hd_var_size (lookup,
613  struct LookupMessage,
614  NULL),
616 
617 
618 /* end of gnunet-service-gns.c */
struct GNUNET_MQ_Handle * mq
Definition: 003.c:5
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
IPC messages between GNS API and GNS service.
uint16_t len
length of data (which is always a uint32_t, but presumably this can be used to specify that fewer byt...
struct GNUNET_IDENTITY_PrivateKey pk
Private key from command line option, or NULL.
static char * pkey
Public key of the zone to look in, in ASCII.
static char * zone
Name of the zone being managed.
static unsigned int rd_count
Number of records for currently parsed set.
static struct GNUNET_GNSRECORD_Data rd[50]
The record data under a single label.
static char * value
Value of the record to add/remove.
static struct GNUNET_SERVICE_Handle * service
Handle to our service instance.
static struct GNS_TopLevelDomain * tld_tail
Tail of DLL of TLDs we map to GNS zones.
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.
static struct GNS_TopLevelDomain * tld_head
Head of DLL of TLDs we map to GNS zones.
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.
static void handle_lookup(void *cls, const struct LookupMessage *sh_msg)
Handle lookup requests from client.
static void shutdown_task(void *cls)
Task run during shutdown.
static struct GNUNET_STATISTICS_Handle * statistics
Handle to the statistics service.
static int v4_enabled
GNUNET_YES if ipv4 is supported
static struct GNUNET_DHT_Handle * dht_handle
Our handle to the DHT.
const char * GNS_get_tld(const char *name)
Obtain the TLD of the given name.
static void read_service_conf(void *cls, const char *section, const char *option, const char *value)
Reads the configuration and populates TLDs.
static void run(void *cls, const struct GNUNET_CONFIGURATION_Handle *c, struct GNUNET_SERVICE_Handle *service)
Process GNS requests.
static int check_lookup(void *cls, const struct LookupMessage *l_msg)
Checks a GNUNET_MESSAGE_TYPE_GNS_LOOKUP message.
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.
static void client_disconnect_cb(void *cls, struct GNUNET_SERVICE_Client *client, void *app_ctx)
Called whenever a client is disconnected.
int GNS_find_tld(const char *tld_str, struct GNUNET_IDENTITY_PublicKey *pkey)
Find GNS zone belonging to TLD tld.
static int v6_enabled
GNUNET_YES if ipv6 is supported
static struct GNUNET_NAMECACHE_Handle * namecache_handle
Our handle to the namecache service.
int GNS_interceptor_init(const struct GNUNET_CONFIGURATION_Handle *c)
Initialize DNS interceptor.
void GNS_interceptor_done()
Disconnect from interceptor.
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.
void GNS_resolver_lookup_cancel(struct GNS_ResolverHandle *rh)
Cancel active resolution (i.e.
struct GNS_ResolverHandle * GNS_resolver_lookup(const struct GNUNET_IDENTITY_PublicKey *zone, uint32_t record_type, const char *name, enum GNUNET_GNS_LocalOptions options, uint16_t recursion_depth_limit, GNS_ResultProcessor proc, void *proc_cls)
Lookup of a record in a specific zone calls lookup result processor on result.
void GNS_resolver_done()
Shutdown resolver.
API to the DHT service.
API to access the DNS service.
API to the GNS service.
API that can be used to manipulate GNS record data.
API that can be used to store naming information on a GNUnet node.
Constants for network protocols.
API to create, modify and access statistics.
enum GNUNET_GenericReturnValue 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.
enum GNUNET_GenericReturnValue 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".
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.
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:1039
void GNUNET_DHT_disconnect(struct GNUNET_DHT_Handle *handle)
Shutdown connection with the DHT service.
Definition: dht_api.c:1062
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
#define GNUNET_DNSPARSER_TYPE_A
#define GNUNET_DNSPARSER_TYPE_AAAA
#define GNUNET_DNSPARSER_MAX_NAME_LENGTH
Maximum length of a name in DNS.
GNUNET_GNS_LocalOptions
Options for the GNS lookup.
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.
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.
int GNUNET_GNSRECORD_zkey_to_pkey(const char *zkey, struct GNUNET_IDENTITY_PublicKey *pkey)
Convert an absolute domain name to the respective public key.
enum GNUNET_GenericReturnValue GNUNET_IDENTITY_read_public_key_from_buffer(const void *buffer, size_t len, struct GNUNET_IDENTITY_PublicKey *key, size_t *kb_read)
Reads a GNUNET_IDENTITY_PublicKey from a compact buffer.
Definition: identity_api.c:865
#define GNUNET_log(kind,...)
@ GNUNET_OK
@ GNUNET_YES
@ GNUNET_NO
@ GNUNET_SYSERR
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur.
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.
@ GNUNET_ERROR_TYPE_ERROR
@ GNUNET_ERROR_TYPE_DEBUG
#define GNUNET_strdup(a)
Wrapper around GNUNET_xstrdup_.
#define GNUNET_new(type)
Allocate a struct or union of the given type.
#define GNUNET_free(ptr)
Wrapper around free.
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:304
#define GNUNET_MQ_handler_end()
End-marker for the handlers array.
#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:62
#define GNUNET_MQ_hd_var_size(name, code, str, ctx)
void GNUNET_NAMECACHE_disconnect(struct GNUNET_NAMECACHE_Handle *h)
Disconnect from the namecache service (and free associated resources).
struct GNUNET_NAMECACHE_Handle * GNUNET_NAMECACHE_connect(const struct GNUNET_CONFIGURATION_Handle *cfg)
Connect to the namecache service.
enum GNUNET_GenericReturnValue GNUNET_NETWORK_test_pf(int pf)
Test if the given protocol family is supported by this system.
Definition: network.c:79
#define GNUNET_MESSAGE_TYPE_GNS_LOOKUP
Client would like to resolve a name.
#define GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT
Service response to name resolution request from client.
void GNUNET_SCHEDULER_shutdown(void)
Request the shutdown of a scheduler.
Definition: scheduler.c:562
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:1299
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,...
Definition: scheduler.c:1334
void GNUNET_SERVICE_client_drop(struct GNUNET_SERVICE_Client *c)
Ask the server to disconnect from the given client.
Definition: service.c:2330
struct GNUNET_MQ_Handle * GNUNET_SERVICE_client_get_mq(struct GNUNET_SERVICE_Client *c)
Obtain the message queue of c.
Definition: service.c:2443
void GNUNET_SERVICE_client_continue(struct GNUNET_SERVICE_Client *c)
Continue receiving further messages from the given client.
Definition: service.c:2249
@ GNUNET_SERVICE_OPTION_NONE
Use defaults.
struct GNUNET_STATISTICS_Handle * GNUNET_STATISTICS_create(const char *subsystem, const struct GNUNET_CONFIGURATION_Handle *cfg)
Get handle for the statistics service.
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_STATISTICS_destroy(struct GNUNET_STATISTICS_Handle *h, int sync_first)
Destroy a handle (free all state associated with it).
enum GNUNET_GenericReturnValue 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:788
#define _(String)
GNU gettext support macro.
Definition: platform.h:177
const char * name
Handle to a lookup operation from client via API.
struct GnsClient * gc
Client handle.
struct ClientLookupHandle * next
We keep these in a DLL.
struct GNS_ResolverHandle * lookup
Active handle for the lookup.
uint32_t request_id
request id
struct ClientLookupHandle * prev
We keep these in a DLL.
Handle to a currently pending resolution.
Representation of a TLD, mapping the respective TLD string (e.g.
struct GNS_TopLevelDomain * prev
Kept in a DLL, as there are unlikely enough of these to warrant a hash map.
char * tld
Top-level domain as a string, including leading ".".
struct GNS_TopLevelDomain * next
Kept in a DLL, as there are unlikely enough of these to warrant a hash map.
struct GNUNET_IDENTITY_PublicKey pkey
Public key associated with the tld.
Connection to the DHT service.
Definition: dht_api.c:237
An identity key as per LSD0001.
Handle to a message queue.
Definition: mq.c:87
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format.
Connection to the NAMECACHE service.
Definition: namecache_api.c:93
Handle to a client that is connected to a service.
Definition: service.c:252
Handle to a service.
Definition: service.c:118
Handle for the service.
Information we track per connected client.
struct ClientLookupHandle * clh_tail
Tail of the DLL.
struct GNUNET_MQ_Handle * mq
The MQ.
struct ClientLookupHandle * clh_head
Head of the DLL.
struct GNUNET_SERVICE_Client * client
The client.
Message from client to GNS service to lookup records.
Definition: gns.h:37
int16_t options
Local options for where to look for results (an enum GNUNET_GNS_LocalOptions in NBO).
Definition: gns.h:52
uint32_t id
Unique identifier for this request (for key collisions).
Definition: gns.h:46
uint32_t key_len
Length of the zone key.
Definition: gns.h:69
struct GNUNET_MessageHeader header
Header of type GNUNET_MESSAGE_TYPE_GNS_LOOKUP.
Definition: gns.h:41
uint16_t recursion_depth_limit
Recursion depth limit, i.e.
Definition: gns.h:59
int32_t type
the type of record to look up
Definition: gns.h:64
Message from GNS service to client: new results.
Definition: gns.h:80
uint32_t id
Unique identifier for this request (for key collisions).
Definition: gns.h:89
uint32_t rd_count
The number of records contained in response.
Definition: gns.h:96