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_template_service.h" */
  34
  35 /**
  36  * Final status code.
  37  */
  38 static int ret;
  39
  40 struct vpn_cls {
  41         struct GNUNET_DISK_PipeHandle* helper_in;
  42         struct GNUNET_DISK_PipeHandle* helper_out;
  43         const struct GNUNET_DISK_FileHandle* fh_from_helper;
  44
  45         struct GNUNET_SCHEDULER_Handle *sched;
  46
  47         pid_t helper_pid;
  48 };
  49
  50 static void cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  51         struct vpn_cls* mycls = (struct vpn_cls*) cls;
  52         if (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) {
  53                 PLIBC_KILL(mycls->helper_pid, SIGTERM);
  54                 GNUNET_OS_process_wait(mycls->helper_pid);
  55         }
  56 }
  57
  58 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx);
  59
  60 static void start_helper_and_schedule(struct vpn_cls* mycls) {
  61         mycls->helper_in = GNUNET_DISK_pipe(1);
  62         mycls->helper_out = GNUNET_DISK_pipe(1);
  63
  64         mycls->helper_pid = GNUNET_OS_start_process(mycls->helper_in, mycls->helper_out, "gnunet-vpn-helper", "gnunet-vpn-helper", NULL);
  65
  66         mycls->fh_from_helper = GNUNET_DISK_pipe_handle (mycls->helper_out, GNUNET_DISK_PIPE_END_READ);
  67
  68         GNUNET_SCHEDULER_add_read_file (mycls->sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls->fh_from_helper, &helper_read, mycls);
  69 }
  70
  71
  72 static void restart_helper(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  73         struct vpn_cls* mycls = (struct vpn_cls*) cls;
  74
  75         // Kill the helper
  76         PLIBC_KILL(mycls->helper_pid, SIGTERM);
  77         GNUNET_OS_process_wait(mycls->helper_pid);
  78
  79         // Restart the helper
  80         start_helper_and_schedule(mycls);
  81
  82 }
  83
  84 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
  85         struct vpn_cls* mycls = (struct vpn_cls*) cls;
  86         struct suid_packet_header hdr = { .size = 0 };
  87
  88         int r = 0;
  89
  90         if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
  91                 return;
  92
  93         while (r < sizeof(struct suid_packet_header)) {
  94                 int t = GNUNET_DISK_file_read(mycls->fh_from_helper, &hdr, sizeof(struct suid_packet_header));
  95                 if (t<=0) {
  96                         fprintf(stderr, "Read error for header: %m\n");
  97                         GNUNET_SCHEDULER_add_now(mycls->sched, restart_helper, cls);
  98                         return;
  99                 }
 100                 r += t;
 101         }
 102
 103         struct suid_packet *pkt = (struct suid_packet*) GNUNET_malloc(ntohl(hdr.size));
 104
 105         memcpy(pkt, &hdr, sizeof(struct suid_packet_header));
 106
 107         while (r < ntohl(pkt->hdr.size)) {
 108                 int t = GNUNET_DISK_file_read(mycls->fh_from_helper, (unsigned char*)pkt + r, ntohl(pkt->hdr.size) - r);
 109                 if (t<=0) {
 110                         fprintf(stderr, "Read error for data: %m\n");
 111                         GNUNET_SCHEDULER_add_now(mycls->sched, restart_helper, cls);
 112                         return;
 113                 }
 114                 r += t;
 115         }
 116
 117         struct ip6_pkt *pkt6 = (struct ip6_pkt*) pkt;
 118         struct ip6_tcp *pkt6_tcp;
 119         struct ip6_udp *pkt6_udp;
 120
 121         pkt_printf(pkt6);
 122         switch(pkt6->ip6_hdr.nxthdr) {
 123                 case 0x06:
 124                         pkt6_tcp = (struct ip6_tcp*)pkt6;
 125                         pkt_printf_ip6tcp(pkt6_tcp);
 126                         break;
 127                 case 0x11:
 128                         pkt6_udp = (struct ip6_udp*)pkt6;
 129                         pkt_printf_ip6udp(pkt6_udp);
 130                         if (ntohs(pkt6_udp->udp_hdr.dpt) == 53) {
 131                                 pkt_printf_ip6dns((struct ip6_udp_dns*)pkt6_udp);
 132                         }
 133                         break;
 134         }
 135
 136         GNUNET_free(pkt);
 137
 138         GNUNET_SCHEDULER_add_read_file (mycls->sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls->fh_from_helper, &helper_read, mycls);
 139 }
 140
 141 /**
 142  * Main function that will be run by the scheduler.
 143  *
 144  * @param cls closure
 145  * @param sched the scheduler to use
 146  * @param args remaining command-line arguments
 147  * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 148  * @param cfg configuration
 149  */
 150 static void
 151 run (void *cls,
 152                 struct GNUNET_SCHEDULER_Handle *sched,
 153                 char *const *args,
 154                 const char *cfgfile,
 155                 const struct GNUNET_CONFIGURATION_Handle *cfg) {
 156
 157         struct vpn_cls* mycls = (struct vpn_cls*) cls;
 158
 159         mycls->sched = sched;
 160
 161         GNUNET_SCHEDULER_add_delayed(sched, GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
 162
 163         start_helper_and_schedule(mycls);
 164 }
 165
 166
 167 /**
 168  * The main function to obtain template from gnunetd.
 169  *
 170  * @param argc number of arguments from the command line
 171  * @param argv command line arguments
 172  * @return 0 ok, 1 on error
 173  */
 174 int
 175 main (int argc, char *const *argv)
 176 {
 177   static const struct GNUNET_GETOPT_CommandLineOption options[] = {
 178     GNUNET_GETOPT_OPTION_END
 179   };
 180
 181   struct vpn_cls* cls = (struct vpn_cls*)malloc(sizeof(struct vpn_cls));
 182
 183   return (GNUNET_OK ==
 184           GNUNET_PROGRAM_run (argc,
 185                               argv,
 186                               "gnunet-daemon-vpn",
 187                               gettext_noop ("help text"),
 188                               options, &run, cls)) ? ret : 1;
 189 }
 190
 191 /* end of gnunet-daemon-vpn.c */