src/vpn/gnunet-daemon-vpn.c

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2010 Christian Grothoff
   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 vpn/gnunet-daemon-vpn.c
  23  * @brief
  24  * @author Philipp Tölke
  25  */
  26 #include "platform.h"
  27 #include "gnunet_getopt_lib.h"
  28 #include "gnunet_program_lib.h"
  29 #include "gnunet_os_lib.h"
  30 #include "gnunet-vpn-helper-p.h"
  31 #include "gnunet-vpn-packet.h"
  32 #include "gnunet-vpn-pretty-print.h"
  33 #include "gnunet_common.h"
  34 #include "gnunet_protocols.h"
  35 #include "gnunet_server_lib.h"
  36 #include "gnunet-service-dns-p.h"
  37 #include "gnunet_client_lib.h"
  38
  39 /**
  40  * Final status code.
  41  */
  42 static int ret;
  43
  44 struct vpn_cls {
  45         struct GNUNET_DISK_PipeHandle* helper_in; // From the helper
  46         struct GNUNET_DISK_PipeHandle* helper_out; // To the helper
  47         const struct GNUNET_DISK_FileHandle* fh_from_helper;
  48
  49         struct GNUNET_SERVER_MessageStreamTokenizer* mst;
  50
  51         struct GNUNET_SCHEDULER_Handle *sched;
  52
  53         struct GNUNET_CLIENT_Connection *dns_connection;
  54
  55         pid_t helper_pid;
  56 };
  57
  58 static struct vpn_cls mycls;
  59
  60 static void cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  61         if (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) {
  62                 PLIBC_KILL(mycls.helper_pid, SIGTERM);
  63                 GNUNET_OS_process_wait(mycls.helper_pid);
  64         }
  65 }
  66
  67 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx);
  68
  69 static void start_helper_and_schedule() {
  70         mycls.helper_in = GNUNET_DISK_pipe(1);
  71         mycls.helper_out = GNUNET_DISK_pipe(1);
  72
  73         mycls.helper_pid = GNUNET_OS_start_process(mycls.helper_in, mycls.helper_out, "gnunet-helper-vpn", "gnunet-helper-vpn", NULL);
  74
  75         mycls.fh_from_helper = GNUNET_DISK_pipe_handle (mycls.helper_out, GNUNET_DISK_PIPE_END_READ);
  76
  77         GNUNET_DISK_pipe_close_end(mycls.helper_out, GNUNET_DISK_PIPE_END_WRITE);
  78         GNUNET_DISK_pipe_close_end(mycls.helper_in, GNUNET_DISK_PIPE_END_READ);
  79
  80         GNUNET_SCHEDULER_add_read_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_from_helper, &helper_read, NULL);
  81 }
  82
  83
  84 static void restart_helper(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  85         // FIXME: Ratelimit this!
  86
  87         // Kill the helper
  88         PLIBC_KILL(mycls.helper_pid, SIGKILL);
  89         GNUNET_OS_process_wait(mycls.helper_pid);
  90
  91         // Restart the helper
  92         start_helper_and_schedule(mycls);
  93
  94 }
  95
  96 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
  97         char buf[65535];
  98
  99         if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
 100                 return;
 101
 102         int t = GNUNET_DISK_file_read(mycls.fh_from_helper, &buf, 65535);
 103         if (t<=0) {
 104                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Read error for header: %m\n");
 105                 GNUNET_SCHEDULER_add_now(mycls.sched, restart_helper, cls);
 106                 return;
 107         }
 108
 109         /* FIXME */ GNUNET_SERVER_mst_receive(mycls.mst, NULL, buf, t, 0, 0);
 110
 111         GNUNET_SCHEDULER_add_read_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_from_helper, &helper_read, NULL);
 112 }
 113
 114 size_t send_query(void* cls, size_t size, void* buf)
 115 {
 116         struct query_packet* pkt = cls;
 117         size_t len = ntohs(pkt->hdr.size);
 118         memcpy(buf, cls, len);
 119         GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sent %d bytes.\n", len);
 120         GNUNET_free(cls);
 121         return len;
 122 }
 123
 124 static void message_token(void *cls, void *client, const struct GNUNET_MessageHeader *message) {
 125         if (ntohs(message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) return;
 126
 127         struct tun_pkt *pkt_tun = (struct tun_pkt*) message;
 128
 129         if (ntohs(pkt_tun->tun.type) == 0x86dd) {
 130                 struct ip6_pkt *pkt6 = (struct ip6_pkt*) message;
 131                 struct ip6_tcp *pkt6_tcp;
 132                 struct ip6_udp *pkt6_udp;
 133
 134                 pkt_printf(pkt6);
 135                 switch(pkt6->ip6_hdr.nxthdr) {
 136                         case 0x06:
 137                                 pkt6_tcp = (struct ip6_tcp*)pkt6;
 138                                 pkt_printf_ip6tcp(pkt6_tcp);
 139                                 break;
 140                         case 0x11:
 141                                 pkt6_udp = (struct ip6_udp*)pkt6;
 142                                 pkt_printf_ip6udp(pkt6_udp);
 143                                 if (ntohs(pkt6_udp->udp_hdr.dpt) == 53) {
 144                                         pkt_printf_ip6dns((struct ip6_udp_dns*)pkt6_udp);
 145                                 }
 146                                 break;
 147                 }
 148         } else if (ntohs(pkt_tun->tun.type) == 0x0800) {
 149                 struct ip_pkt *pkt = (struct ip_pkt*) message;
 150                 struct ip_udp *udp = (struct ip_udp*) message;
 151                 if (pkt->ip_hdr.proto == 0x11 && udp->ip_hdr.dadr == 0x020a0a0a && ntohs(udp->udp_hdr.dpt) == 53 ) {
 152                         size_t len = sizeof(struct query_packet) + ntohs(udp->udp_hdr.len) - 9; /* 7 = 8 for the udp-header + 1 for the unsigned char data[1]; */
 153                         struct query_packet* query = GNUNET_malloc(len);
 154                         query->hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS);
 155                         query->hdr.size = htons(len);
 156                         query->orig_to = pkt->ip_hdr.dadr;
 157                         query->orig_from = pkt->ip_hdr.sadr;
 158                         query->src_port = udp->udp_hdr.spt;
 159                         memcpy(query->data, udp->data, ntohs(udp->udp_hdr.len) - 8);
 160                         struct GNUNET_CLIENT_TransmitHandle* th = GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, len, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, query);
 161                         if (th != NULL)
 162                                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Queued sending of %d bytes.\n", len);
 163                         else
 164                                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Already queued!\n");
 165                 }
 166         }
 167
 168 }
 169
 170 /**
 171  * Main function that will be run by the scheduler.
 172  *
 173  * @param cls closure
 174  * @param sched the scheduler to use
 175  * @param args remaining command-line arguments
 176  * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 177  * @param cfg configuration
 178  */
 179 static void
 180 run (void *cls,
 181      struct GNUNET_SCHEDULER_Handle *sched,
 182      char *const *args,
 183      const char *cfgfile,
 184      const struct GNUNET_CONFIGURATION_Handle *cfg)
 185 {
 186   mycls.sched = sched;
 187   mycls.mst = GNUNET_SERVER_mst_create(&message_token, NULL);
 188
 189   mycls.dns_connection = GNUNET_CLIENT_connect (sched, "gnunet-service-dns", cfg);
 190   GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connection: %x\n", mycls.dns_connection);
 191
 192   GNUNET_SCHEDULER_add_delayed(sched, GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
 193   start_helper_and_schedule(mycls);
 194 }
 195
 196
 197 /**
 198  * The main function to obtain template from gnunetd.
 199  *
 200  * @param argc number of arguments from the command line
 201  * @param argv command line arguments
 202  * @return 0 ok, 1 on error
 203  */
 204 int
 205 main (int argc, char *const *argv)
 206 {
 207   static const struct GNUNET_GETOPT_CommandLineOption options[] = {
 208     GNUNET_GETOPT_OPTION_END
 209   };
 210
 211   return (GNUNET_OK ==
 212           GNUNET_PROGRAM_run (argc,
 213                               argv,
 214                               "gnunet-daemon-vpn",
 215                               gettext_noop ("help text"),
 216                               options, &run, NULL)) ? ret : 1;
 217 }
 218
 219 /* end of gnunet-daemon-vpn.c */