src/gns/gnunet-service-gns.c

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2009, 2010, 2011 Christian Grothoff (and other contributing authors)
   4
   5      GNUnet is free software; you can redistribute it and/or modify
   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.
   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      General Public License for more details.
  14
  15      You should have received a copy of the GNU General Public License
  16      along with GNUnet; see the file COPYING.  If not, write to the
  17      Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18      Boston, MA 02111-1307, USA.
  19 */
  20
  21 /**
  22  * @file gns/gnunet-service-gns.c
  23  * @brief GNUnet GNS service
  24  * @author Martin Schanzenbach
  25  */
  26 #include "platform.h"
  27 #include "gnunet_util_lib.h"
  28 #include "gnunet_transport_service.h"
  29 #include "gnunet_dns_service.h"
  30 #include "gnunet_gns_service.h"
  31 #include "gnunet-service-gns.h"
  32
  33
  34 /**
  35  * Our handle to the DNS handler library
  36  */
  37 struct GNUNET_DNS_Handle *dns_handler;
  38
  39 /**
  40  * The configuration the GNS service is running with
  41  */
  42 const struct GNUNET_CONFIGURATION_Handle *GNS_cfg;
  43
  44 /**
  45  * Task run during shutdown.
  46  *
  47  * @param cls unused
  48  * @param tc unused
  49  */
  50 static void
  51 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
  52 {
  53         GNUNET_DNS_disconnect(dns_handle);
  54 }
  55
  56 /**
  57  * The DNS request handler
  58  *
  59  * @param cls closure
  60  * @param rh request handle to user for reply
  61  * @param request_length number of bytes in request
  62  * @param request udp payload of the DNS request
  63  */
  64 void
  65 handle_dns_request(void *cls,
  66                                                                          struct GNUNET_DNS_RequestHandle *rh,
  67                                                                          size_t request_length,
  68                                                                          const char *request)
  69 {
  70         /**
  71          * TODO: parse request for tld
  72          * Queue rh and gns handle (or use cls)
  73          * How should lookup behave:
  74          *  - sync and return result or "NX"
  75          *  - async like dht with iter
  76          *  Maybe provide both, useful for cli app
  77          **/
  78   struct GNUNET_DNSPARSER_Packet *p;
  79         int namelen;
  80
  81         p = GNUNET_DNSPARSER_parse (request, request_length);
  82         if (NULL == p)
  83         {
  84                 fprintf (stderr, "Received malformed DNS packet, leaving it untouched\n");
  85                 GNUNET_DNS_request_forward (rh);
  86                 return;
  87         }
  88         /**
  89          * TODO factor out
  90          * Check tld and decide if we or
  91          * legacy dns is responsible
  92          **/
  93         for (i=0;i<p->num_queries;i++)
  94         {
  95                 namelen = strlen(&p->queries[i]->name);
  96                 if (namelen >= 7)
  97                 {
  98                         /**
  99                          * TODO off by 1?
 100                          * Move our tld/root to config file
 101                          * Generate fake DNS reply that replaces .gnunet with .org
 102                          **/
 103                         if (0 == strcmp((&p->queries[i]->name)+(namelen-7), ".gnunet"))
 104                         {
 105                                 GNUNET_DNS_request_answer(rh, 0 /*length*/, NULL/*reply*/);
 106                         }
 107                         else
 108                         {
 109                                 GNUNET_DNS_request_forward (rh);
 110                         }
 111                 }
 112         }
 113 }
 114
 115
 116 /**
 117  * Process GNS requests.
 118  *
 119  * @param cls closure
 120  * @param server the initialized server
 121  * @param c configuration to use
 122  */
 123 static void
 124 run (void *cls, struct GNUNET_SERVER_Handle *server,
 125      const struct GNUNET_CONFIGURATION_Handle *c)
 126 {
 127         /* The IPC message types */
 128         static const struct GNUNET_SERVER_MessageHandler handlers[] = {
 129                 /* callback, cls, type, size */
 130                 {&handle_client_record_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_RECORD_LOOKUP,
 131                         sizeof (struct GNUNET_GNS_Lookup)},
 132                 {&handle_client_record_add, NULL, GNUNET_MESSAGE_TYPE_GNS_RECORD_ADD,
 133                         sizeof (struct GNUNET_GNS_Record)},
 134                 {NULL, NULL, 0, 0}
 135         };
 136
 137         nc = GNUNET_SERVER_notification_context_create (server, 1);
 138
 139         /* TODO do some config parsing */
 140
 141         GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
 142                                 NULL);
 143         /**
 144          * Do gnunet dns init here
 145          * */
 146         dns_handle = GNUNET_DNS_connect(c,
 147                                                                                                                                         GNUNET_DNS_FLAG_PRE_RESOLUTION,
 148                                                                                                                                         &handle_dns_request, /* rh */
 149                                                                                                                                         NULL); /* Closure */
 150         GNUNET_SERVER_add_handlers (server, handlers);
 151         /**
 152          * Esp the lookup would require to keep track of the clients' context
 153          * See dht.
 154          * GNUNET_SERVER_disconnect_notify (server, &client_disconnect, NULL);
 155          **/
 156 }
 157
 158
 159 /**
 160  * The main function for the GNS service.
 161  *
 162  * @param argc number of arguments from the command line
 163  * @param argv command line arguments
 164  * @return 0 ok, 1 on error
 165  */
 166 int
 167 main (int argc, char *const *argv)
 168 {
 169   int ret;
 170
 171   ret =
 172       (GNUNET_OK ==
 173        GNUNET_SERVICE_run (argc, argv, "gns", GNUNET_SERVICE_OPTION_NONE, &run,
 174                            NULL)) ? 0 : 1;
 175   return ret;
 176 }
 177
 178 /* end of gnunet-service-gns.c */