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_template_service.h" */
  36
  37 /**
  38  * Final status code.
  39  */
  40 static int ret;
  41
  42 struct vpn_cls {
  43         struct GNUNET_DISK_PipeHandle* helper_in;
  44         struct GNUNET_DISK_PipeHandle* helper_out;
  45         const struct GNUNET_DISK_FileHandle* fh_from_helper;
  46
  47         struct GNUNET_SCHEDULER_Handle *sched;
  48
  49         pid_t helper_pid;
  50 };
  51
  52 static void cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  53         struct vpn_cls* mycls = (struct vpn_cls*) cls;
  54         if (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) {
  55                 PLIBC_KILL(mycls->helper_pid, SIGTERM);
  56                 GNUNET_OS_process_wait(mycls->helper_pid);
  57         }
  58 }
  59
  60 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx);
  61
  62 static void start_helper_and_schedule(struct vpn_cls* mycls) {
  63         mycls->helper_in = GNUNET_DISK_pipe(1);
  64         mycls->helper_out = GNUNET_DISK_pipe(1);
  65
  66         mycls->helper_pid = GNUNET_OS_start_process(mycls->helper_in, mycls->helper_out, "gnunet-vpn-helper", "gnunet-vpn-helper", NULL);
  67
  68         mycls->fh_from_helper = GNUNET_DISK_pipe_handle (mycls->helper_out, GNUNET_DISK_PIPE_END_READ);
  69
  70         GNUNET_DISK_pipe_close_end(mycls->helper_out, GNUNET_DISK_PIPE_END_WRITE);
  71         GNUNET_DISK_pipe_close_end(mycls->helper_in, GNUNET_DISK_PIPE_END_READ);
  72
  73         GNUNET_SCHEDULER_add_read_file (mycls->sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls->fh_from_helper, &helper_read, mycls);
  74 }
  75
  76
  77 static void restart_helper(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  78         struct vpn_cls* mycls = (struct vpn_cls*) cls;
  79
  80         // Kill the helper
  81         PLIBC_KILL(mycls->helper_pid, SIGTERM);
  82         GNUNET_OS_process_wait(mycls->helper_pid);
  83
  84         // Restart the helper
  85         start_helper_and_schedule(mycls);
  86
  87 }
  88
  89 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
  90         struct vpn_cls* mycls = (struct vpn_cls*) cls;
  91         struct GNUNET_MessageHeader hdr = { .size = 0, .type = 0 };
  92
  93         int r = 0;
  94
  95         if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
  96                 return;
  97
  98         while (r < sizeof(struct GNUNET_MessageHeader)) {
  99                 int t = GNUNET_DISK_file_read(mycls->fh_from_helper, &hdr, sizeof(struct GNUNET_MessageHeader));
 100                 if (t<=0) {
 101                         fprintf(stderr, "Read error for header: %m\n");
 102                         GNUNET_SCHEDULER_add_now(mycls->sched, restart_helper, cls);
 103                         return;
 104                 }
 105                 r += t;
 106         }
 107
 108         struct suid_packet *pkt = (struct suid_packet*) GNUNET_malloc(ntohs(hdr.size));
 109
 110         memcpy(pkt, &hdr, sizeof(struct GNUNET_MessageHeader));
 111
 112         while (r < ntohs(pkt->hdr.size)) {
 113                 int t = GNUNET_DISK_file_read(mycls->fh_from_helper, (unsigned char*)pkt + r, ntohs(pkt->hdr.size) - r);
 114                 if (t<=0) {
 115                         fprintf(stderr, "Read error for data: %m\n");
 116                         GNUNET_SCHEDULER_add_now(mycls->sched, restart_helper, cls);
 117                         return;
 118                 }
 119                 r += t;
 120         }
 121
 122         struct ip6_pkt *pkt6 = (struct ip6_pkt*) pkt;
 123         struct ip6_tcp *pkt6_tcp;
 124         struct ip6_udp *pkt6_udp;
 125
 126         pkt_printf(pkt6);
 127         switch(pkt6->ip6_hdr.nxthdr) {
 128                 case 0x06:
 129                         pkt6_tcp = (struct ip6_tcp*)pkt6;
 130                         pkt_printf_ip6tcp(pkt6_tcp);
 131                         break;
 132                 case 0x11:
 133                         pkt6_udp = (struct ip6_udp*)pkt6;
 134                         pkt_printf_ip6udp(pkt6_udp);
 135                         if (ntohs(pkt6_udp->udp_hdr.dpt) == 53) {
 136                                 pkt_printf_ip6dns((struct ip6_udp_dns*)pkt6_udp);
 137                         }
 138                         break;
 139         }
 140
 141         GNUNET_free(pkt);
 142
 143         GNUNET_SCHEDULER_add_read_file (mycls->sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls->fh_from_helper, &helper_read, mycls);
 144 }
 145
 146 /**
 147  * Main function that will be run by the scheduler.
 148  *
 149  * @param cls closure
 150  * @param sched the scheduler to use
 151  * @param args remaining command-line arguments
 152  * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 153  * @param cfg configuration
 154  */
 155 static void
 156 run (void *cls,
 157                 struct GNUNET_SCHEDULER_Handle *sched,
 158                 char *const *args,
 159                 const char *cfgfile,
 160                 const struct GNUNET_CONFIGURATION_Handle *cfg) {
 161
 162         struct vpn_cls* mycls = (struct vpn_cls*) cls;
 163
 164         mycls->sched = sched;
 165
 166         GNUNET_SCHEDULER_add_delayed(sched, GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
 167
 168         start_helper_and_schedule(mycls);
 169 }
 170
 171
 172 /**
 173  * The main function to obtain template from gnunetd.
 174  *
 175  * @param argc number of arguments from the command line
 176  * @param argv command line arguments
 177  * @return 0 ok, 1 on error
 178  */
 179 int
 180 main (int argc, char *const *argv)
 181 {
 182   static const struct GNUNET_GETOPT_CommandLineOption options[] = {
 183     GNUNET_GETOPT_OPTION_END
 184   };
 185
 186   struct vpn_cls* cls = (struct vpn_cls*)malloc(sizeof(struct vpn_cls));
 187
 188   return (GNUNET_OK ==
 189           GNUNET_PROGRAM_run (argc,
 190                               argv,
 191                               "gnunet-daemon-vpn",
 192                               gettext_noop ("help text"),
 193                               options, &run, cls)) ? ret : 1;
 194 }
 195
 196 /* end of gnunet-daemon-vpn.c */