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 #include "gnunet_container_lib.h"
  39
  40 /**
  41  * Final status code.
  42  */
  43 static int ret;
  44
  45 struct vpn_cls {
  46         struct GNUNET_DISK_PipeHandle* helper_in; // From the helper
  47         struct GNUNET_DISK_PipeHandle* helper_out; // To the helper
  48         const struct GNUNET_DISK_FileHandle* fh_from_helper;
  49
  50         struct GNUNET_SERVER_MessageStreamTokenizer* mst;
  51
  52         struct GNUNET_SCHEDULER_Handle *sched;
  53
  54         struct GNUNET_CLIENT_Connection *dns_connection;
  55
  56         pid_t helper_pid;
  57
  58         struct GNUNET_CONTAINER_SList *query_queue;
  59 };
  60
  61 static struct vpn_cls mycls;
  62
  63 static void cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  64         if (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) {
  65                 PLIBC_KILL(mycls.helper_pid, SIGTERM);
  66                 GNUNET_OS_process_wait(mycls.helper_pid);
  67         }
  68 }
  69
  70 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx);
  71
  72 static void start_helper_and_schedule() {
  73         mycls.helper_in = GNUNET_DISK_pipe(GNUNET_YES);
  74         mycls.helper_out = GNUNET_DISK_pipe(GNUNET_YES);
  75
  76         if (mycls.helper_in == NULL || mycls.helper_out == NULL) return;
  77
  78         mycls.helper_pid = GNUNET_OS_start_process(mycls.helper_in, mycls.helper_out, "gnunet-helper-vpn", "gnunet-helper-vpn", NULL);
  79
  80         mycls.fh_from_helper = GNUNET_DISK_pipe_handle (mycls.helper_out, GNUNET_DISK_PIPE_END_READ);
  81
  82         GNUNET_DISK_pipe_close_end(mycls.helper_out, GNUNET_DISK_PIPE_END_WRITE);
  83         GNUNET_DISK_pipe_close_end(mycls.helper_in, GNUNET_DISK_PIPE_END_READ);
  84
  85         GNUNET_SCHEDULER_add_read_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_from_helper, &helper_read, NULL);
  86 }
  87
  88
  89 static void restart_helper(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  90         // FIXME: Ratelimit this!
  91
  92         // Kill the helper
  93         PLIBC_KILL(mycls.helper_pid, SIGKILL);
  94         GNUNET_OS_process_wait(mycls.helper_pid);
  95
  96         // Restart the helper
  97         start_helper_and_schedule(mycls);
  98
  99 }
 100
 101 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
 102         char buf[65535];
 103
 104         if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
 105                 return;
 106
 107         int t = GNUNET_DISK_file_read(mycls.fh_from_helper, &buf, 65535);
 108         if (t<=0) {
 109                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Read error for header: %m\n");
 110                 GNUNET_SCHEDULER_add_now(mycls.sched, restart_helper, cls);
 111                 return;
 112         }
 113
 114         /* FIXME */ GNUNET_SERVER_mst_receive(mycls.mst, NULL, buf, t, 0, 0);
 115
 116         GNUNET_SCHEDULER_add_read_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_from_helper, &helper_read, NULL);
 117 }
 118
 119 size_t send_query(void* cls, size_t size, void* buf)
 120 {
 121         struct GNUNET_CONTAINER_SList_Iterator *start = GNUNET_CONTAINER_slist_begin (mycls.query_queue);
 122
 123         GNUNET_assert(GNUNET_CONTAINER_slist_count(mycls.query_queue) > 0);
 124
 125         GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "There are %d queries pending.\n", GNUNET_CONTAINER_slist_count(mycls.query_queue));
 126
 127         size_t len;
 128         struct query_packet* pkt = (struct query_packet*)GNUNET_CONTAINER_slist_get(start, &len);
 129
 130         GNUNET_assert(ntohs(pkt->hdr.size) == len);
 131         GNUNET_assert(len <= size);
 132
 133         memcpy(buf, pkt, len);
 134         GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sent %d bytes.\n", len);
 135
 136         GNUNET_CONTAINER_slist_erase(start);
 137         GNUNET_CONTAINER_slist_iter_destroy(start);
 138
 139         if (GNUNET_CONTAINER_slist_count(mycls.query_queue) > 0) {
 140                 start = GNUNET_CONTAINER_slist_begin (mycls.query_queue);
 141                 GNUNET_assert(GNUNET_CONTAINER_slist_end(start) != GNUNET_YES);
 142                 pkt = (struct query_packet*)GNUNET_CONTAINER_slist_get(start, &len);
 143                 GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, len, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
 144         }
 145
 146         return len;
 147 }
 148
 149 static void message_token(void *cls, void *client, const struct GNUNET_MessageHeader *message) {
 150         if (ntohs(message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) return;
 151
 152         struct tun_pkt *pkt_tun = (struct tun_pkt*) message;
 153
 154         if (ntohs(pkt_tun->tun.type) == 0x86dd) {
 155                 struct ip6_pkt *pkt6 = (struct ip6_pkt*) message;
 156                 struct ip6_tcp *pkt6_tcp;
 157                 struct ip6_udp *pkt6_udp;
 158
 159                 pkt_printf(pkt6);
 160                 switch(pkt6->ip6_hdr.nxthdr) {
 161                         case 0x06:
 162                                 pkt6_tcp = (struct ip6_tcp*)pkt6;
 163                                 pkt_printf_ip6tcp(pkt6_tcp);
 164                                 break;
 165                         case 0x11:
 166                                 pkt6_udp = (struct ip6_udp*)pkt6;
 167                                 pkt_printf_ip6udp(pkt6_udp);
 168                                 if (ntohs(pkt6_udp->udp_hdr.dpt) == 53) {
 169                                         pkt_printf_ip6dns((struct ip6_udp_dns*)pkt6_udp);
 170                                 }
 171                                 break;
 172                 }
 173         } else if (ntohs(pkt_tun->tun.type) == 0x0800) {
 174                 struct ip_pkt *pkt = (struct ip_pkt*) message;
 175                 struct ip_udp *udp = (struct ip_udp*) message;
 176                 if (pkt->ip_hdr.proto == 0x11 && udp->ip_hdr.dadr == 0x020a0a0a && ntohs(udp->udp_hdr.dpt) == 53 ) {
 177                         size_t len = sizeof(struct query_packet) + ntohs(udp->udp_hdr.len) - 9; /* 9 = 8 for the udp-header + 1 for the unsigned char data[1]; */
 178                         struct query_packet* query = GNUNET_malloc(len);
 179                         query->hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS);
 180                         query->hdr.size = htons(len);
 181                         query->orig_to = pkt->ip_hdr.dadr;
 182                         query->orig_from = pkt->ip_hdr.sadr;
 183                         query->src_port = udp->udp_hdr.spt;
 184                         memcpy(query->data, udp->data, ntohs(udp->udp_hdr.len) - 8);
 185
 186                         GNUNET_CONTAINER_slist_add_end (mycls.query_queue, GNUNET_CONTAINER_SLIST_DISPOSITION_DYNAMIC, query, len);
 187
 188                         struct GNUNET_CLIENT_TransmitHandle* th = GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, len, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
 189                         if (th != NULL)
 190                                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Queued sending of %d bytes.\n", len);
 191                         else
 192                                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Already queued for %d bytes.\n", len);
 193                 }
 194         }
 195
 196 }
 197
 198 /**
 199  * Main function that will be run by the scheduler.
 200  *
 201  * @param cls closure
 202  * @param sched the scheduler to use
 203  * @param args remaining command-line arguments
 204  * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 205  * @param cfg configuration
 206  */
 207 static void
 208 run (void *cls,
 209      struct GNUNET_SCHEDULER_Handle *sched,
 210      char *const *args,
 211      const char *cfgfile,
 212      const struct GNUNET_CONFIGURATION_Handle *cfg)
 213 {
 214   mycls.sched = sched;
 215   mycls.mst = GNUNET_SERVER_mst_create(&message_token, NULL);
 216
 217   mycls.query_queue = GNUNET_CONTAINER_slist_create();
 218   GNUNET_assert(GNUNET_CONTAINER_slist_count(mycls.query_queue) == 0);
 219
 220   mycls.dns_connection = GNUNET_CLIENT_connect (sched, "gnunet-service-dns", cfg);
 221   GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connection: %x\n", mycls.dns_connection);
 222
 223   GNUNET_SCHEDULER_add_delayed(sched, GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
 224   start_helper_and_schedule(mycls);
 225 }
 226
 227
 228 /**
 229  * The main function to obtain template from gnunetd.
 230  *
 231  * @param argc number of arguments from the command line
 232  * @param argv command line arguments
 233  * @return 0 ok, 1 on error
 234  */
 235 int
 236 main (int argc, char *const *argv)
 237 {
 238   static const struct GNUNET_GETOPT_CommandLineOption options[] = {
 239     GNUNET_GETOPT_OPTION_END
 240   };
 241
 242   return (GNUNET_OK ==
 243           GNUNET_PROGRAM_run (argc,
 244                               argv,
 245                               "gnunet-daemon-vpn",
 246                               gettext_noop ("help text"),
 247                               options, &run, NULL)) ? ret : 1;
 248 }
 249
 250 /* end of gnunet-daemon-vpn.c */