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 query_packet_list *head;
  59         struct query_packet_list *tail;
  60 };
  61
  62 static struct vpn_cls mycls;
  63
  64 static void cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  65         if (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) {
  66                 PLIBC_KILL(mycls.helper_pid, SIGTERM);
  67                 GNUNET_OS_process_wait(mycls.helper_pid);
  68         }
  69 }
  70
  71 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx);
  72
  73 static void start_helper_and_schedule() {
  74         mycls.helper_in = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_YES, GNUNET_NO);;
  75         mycls.helper_out = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_NO, GNUNET_YES);
  76
  77         if (mycls.helper_in == NULL || mycls.helper_out == NULL) return;
  78
  79         mycls.helper_pid = GNUNET_OS_start_process(mycls.helper_in, mycls.helper_out, "gnunet-helper-vpn", "gnunet-helper-vpn", NULL);
  80
  81         mycls.fh_from_helper = GNUNET_DISK_pipe_handle (mycls.helper_out, GNUNET_DISK_PIPE_END_READ);
  82
  83         GNUNET_DISK_pipe_close_end(mycls.helper_out, GNUNET_DISK_PIPE_END_WRITE);
  84         GNUNET_DISK_pipe_close_end(mycls.helper_in, GNUNET_DISK_PIPE_END_READ);
  85
  86         GNUNET_SCHEDULER_add_read_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_from_helper, &helper_read, NULL);
  87 }
  88
  89
  90 static void restart_helper(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
  91         // FIXME: Ratelimit this!
  92
  93         // Kill the helper
  94         PLIBC_KILL(mycls.helper_pid, SIGKILL);
  95         GNUNET_OS_process_wait(mycls.helper_pid);
  96
  97         GNUNET_DISK_pipe_close(mycls.helper_in);
  98         GNUNET_DISK_pipe_close(mycls.helper_out);
  99
 100         // Restart the helper
 101         start_helper_and_schedule(mycls);
 102
 103 }
 104
 105 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
 106         char buf[65535];
 107
 108         if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
 109                 return;
 110
 111         int t = GNUNET_DISK_file_read(mycls.fh_from_helper, &buf, 65535);
 112         if (t<=0) {
 113                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Read error for header: %m\n");
 114                 GNUNET_SCHEDULER_add_now(mycls.sched, restart_helper, cls);
 115                 return;
 116         }
 117
 118         /* FIXME */ GNUNET_SERVER_mst_receive(mycls.mst, NULL, buf, t, 0, 0);
 119
 120         GNUNET_SCHEDULER_add_read_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_from_helper, &helper_read, NULL);
 121 }
 122
 123 size_t send_query(void* cls, size_t size, void* buf)
 124 {
 125         struct query_packet_list* query = mycls.head;
 126         size_t len = ntohs(query->pkt.hdr.size);
 127
 128         GNUNET_assert(len <= size);
 129
 130         memcpy(buf, &query->pkt.hdr, len);
 131
 132         GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sent %d bytes.\n", len);
 133
 134         GNUNET_CONTAINER_DLL_remove (mycls.head, mycls.tail, query);
 135
 136         GNUNET_free(query);
 137
 138         if (mycls.head != NULL) {
 139                 GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, ntohs(mycls.head->pkt.hdr.size), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
 140         }
 141
 142         return len;
 143 }
 144
 145 static void message_token(void *cls, void *client, const struct GNUNET_MessageHeader *message) {
 146         if (ntohs(message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) return;
 147
 148         struct tun_pkt *pkt_tun = (struct tun_pkt*) message;
 149
 150         if (ntohs(pkt_tun->tun.type) == 0x86dd) {
 151                 struct ip6_pkt *pkt6 = (struct ip6_pkt*) message;
 152                 struct ip6_tcp *pkt6_tcp;
 153                 struct ip6_udp *pkt6_udp;
 154
 155                 pkt_printf(pkt6);
 156                 switch(pkt6->ip6_hdr.nxthdr) {
 157                         case 0x06:
 158                                 pkt6_tcp = (struct ip6_tcp*)pkt6;
 159                                 pkt_printf_ip6tcp(pkt6_tcp);
 160                                 break;
 161                         case 0x11:
 162                                 pkt6_udp = (struct ip6_udp*)pkt6;
 163                                 pkt_printf_ip6udp(pkt6_udp);
 164                                 if (ntohs(pkt6_udp->udp_hdr.dpt) == 53) {
 165                                         pkt_printf_ip6dns((struct ip6_udp_dns*)pkt6_udp);
 166                                 }
 167                                 break;
 168                 }
 169         } else if (ntohs(pkt_tun->tun.type) == 0x0800) {
 170                 struct ip_pkt *pkt = (struct ip_pkt*) message;
 171                 struct ip_udp *udp = (struct ip_udp*) message;
 172                 if (pkt->ip_hdr.proto == 0x11 && ntohs(udp->udp_hdr.dpt) == 53 ) {
 173                         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]; */
 174                         struct query_packet_list* query = GNUNET_malloc(len + 2*sizeof(struct query_packet_list*));
 175                         query->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS);
 176                         query->pkt.hdr.size = htons(len);
 177                         query->pkt.orig_to = pkt->ip_hdr.dadr;
 178                         query->pkt.orig_from = pkt->ip_hdr.sadr;
 179                         query->pkt.src_port = udp->udp_hdr.spt;
 180                         memcpy(query->pkt.data, udp->data, ntohs(udp->udp_hdr.len) - 8);
 181
 182                         GNUNET_CONTAINER_DLL_insert_after(mycls.head, mycls.tail, mycls.tail, query);
 183
 184                         struct GNUNET_CLIENT_TransmitHandle* th = GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, len, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
 185                         if (th != NULL)
 186                                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Queued sending of %d bytes.\n", len);
 187                         else
 188                                 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Already queued for %d bytes.\n", len);
 189                 }
 190         }
 191
 192 }
 193
 194 /**
 195  * Main function that will be run by the scheduler.
 196  *
 197  * @param cls closure
 198  * @param sched the scheduler to use
 199  * @param args remaining command-line arguments
 200  * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 201  * @param cfg configuration
 202  */
 203 static void
 204 run (void *cls,
 205      struct GNUNET_SCHEDULER_Handle *sched,
 206      char *const *args,
 207      const char *cfgfile,
 208      const struct GNUNET_CONFIGURATION_Handle *cfg)
 209 {
 210   mycls.sched = sched;
 211   mycls.mst = GNUNET_SERVER_mst_create(&message_token, NULL);
 212
 213   mycls.dns_connection = GNUNET_CLIENT_connect (sched, "dns", cfg);
 214   GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connection: %x\n", mycls.dns_connection);
 215
 216   GNUNET_SCHEDULER_add_delayed(sched, GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
 217   start_helper_and_schedule(mycls);
 218 }
 219
 220
 221 /**
 222  * The main function to obtain template from gnunetd.
 223  *
 224  * @param argc number of arguments from the command line
 225  * @param argv command line arguments
 226  * @return 0 ok, 1 on error
 227  */
 228 int
 229 main (int argc, char *const *argv)
 230 {
 231   static const struct GNUNET_GETOPT_CommandLineOption options[] = {
 232     GNUNET_GETOPT_OPTION_END
 233   };
 234
 235   return (GNUNET_OK ==
 236           GNUNET_PROGRAM_run (argc,
 237                               argv,
 238                               "gnunet-daemon-vpn",
 239                               gettext_noop ("help text"),
 240                               options, &run, NULL)) ? ret : 1;
 241 }
 242
 243 /* end of gnunet-daemon-vpn.c */