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/*
This file is part of GNUnet.
(C) 2009 Christian Grothoff (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
by the Free Software Foundation; either version 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNUnet; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
*/
/**
* @file vpn/gnunet-service-dns.c
* @author Philipp Tölke
*/
#include "platform.h"
#include "gnunet_getopt_lib.h"
#include "gnunet_service_lib.h"
#include "gnunet_network_lib.h"
#include "gnunet_os_lib.h"
#include "gnunet-service-dns-p.h"
#include "gnunet_protocols.h"
#include "gnunet-vpn-packet.h"
#include "gnunet-vpn-pretty-print.h"
struct dns_cls {
struct GNUNET_SCHEDULER_Handle *sched;
struct GNUNET_NETWORK_Handle *dnsout;
unsigned short dnsoutport;
};
static struct dns_cls mycls;
void hijack(unsigned short port) {
char port_s[6];
snprintf(port_s, 6, "%d", port);
GNUNET_OS_start_process(NULL, NULL, "gnunet-helper-hijack-dns", "gnunet-hijack-dns", port_s, NULL);
}
void unhijack(unsigned short port) {
char port_s[6];
snprintf(port_s, 6, "%d", port);
GNUNET_OS_start_process(NULL, NULL, "gnunet-helper-hijack-dns", "gnunet-hijack-dns", "-d", port_s, NULL);
}
void receive_query(void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message)
{
GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Received query!\n");
struct query_packet* pkt = (struct query_packet*)message;
struct dns_pkt* dns = (struct dns_pkt*)pkt->data;
pkt_printf_dns(dns);
GNUNET_SERVER_receive_done(client, GNUNET_OK);
}
/**
* Task run during shutdown.
*
* @param cls unused
* @param tc unused
*/
static void
cleanup_task (void *cls,
const struct GNUNET_SCHEDULER_TaskContext *tc)
{
unhijack(mycls.dnsoutport);
}
/**
* @param cls closure
* @param sched scheduler to use
* @param server the initialized server
* @param cfg configuration to use
*/
static void
run (void *cls,
struct GNUNET_SCHEDULER_Handle *sched,
struct GNUNET_SERVER_Handle *server,
const struct GNUNET_CONFIGURATION_Handle *cfg)
{
static const struct GNUNET_SERVER_MessageHandler handlers[] = {
/* callback, cls, type, size */
{&receive_query, NULL, GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS, 0},
{NULL, NULL, 0, 0}
};
mycls.sched = sched;
mycls.dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
struct sockaddr_in addr;
memset(&addr, 0, sizeof(struct sockaddr_in));
int err = GNUNET_NETWORK_socket_bind (mycls.dnsout, (struct sockaddr*)&addr, sizeof(struct sockaddr_in));
err = getsockname(GNUNET_NETWORK_get_fd(mycls.dnsout), &addr, (unsigned int[]){sizeof(struct sockaddr_in)});
mycls.dnsoutport = htons(addr.sin_port);
hijack(htons(addr.sin_port));
GNUNET_SERVER_add_handlers (server, handlers);
GNUNET_SCHEDULER_add_delayed (sched,
GNUNET_TIME_UNIT_FOREVER_REL,
&cleanup_task,
cls);
}
/**
* The main function for the dns service.
*
* @param argc number of arguments from the command line
* @param argv command line arguments
* @return 0 ok, 1 on error
*/
int
main (int argc, char *const *argv)
{
return (GNUNET_OK ==
GNUNET_SERVICE_run (argc,
argv,
"gnunet-service-dns",
GNUNET_SERVICE_OPTION_NONE,
&run, NULL)) ? 0 : 1;
}
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