2 This file is part of GNUnet.
3 Copyright (C) 2010, 2011, 2012, 2016 Christian Grothoff
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.
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.
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., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
22 * @file vpn/gnunet-service-vpn.c
23 * @brief service that opens a virtual interface and allows its clients
24 * to allocate IPs on the virtual interface and to then redirect
25 * IP traffic received on those IPs via the GNUnet cadet
26 * @author Philipp Toelke
27 * @author Christian Grothoff
30 * - keep multiple peers/cadet channels ready as alternative exits /
31 * detect & recover from channel-to-exit failure gracefully
34 #include "gnunet_util_lib.h"
35 #include "gnunet_common.h"
36 #include "gnunet_protocols.h"
37 #include "gnunet_applications.h"
38 #include "gnunet_cadet_service.h"
39 #include "gnunet_statistics_service.h"
40 #include "gnunet_constants.h"
41 #include "gnunet_tun_lib.h"
42 #include "gnunet_regex_service.h"
48 * Maximum number of messages we allow in the queue for cadet.
50 #define MAX_MESSAGE_QUEUE_SIZE 4
54 * State we keep for each of our channels.
59 * Information we track for each IP address to determine which channel
60 * to send the traffic over to the destination.
62 struct DestinationEntry;
65 * List of channels we keep for each destination port for a given
68 struct DestinationChannel
74 struct DestinationChannel *next;
79 struct DestinationChannel *prev;
82 * Destination entry list this `struct DestinationChannel` belongs with.
84 struct DestinationEntry *destination;
87 * Destination port this channel state is used for.
89 uint16_t destination_port;
95 * Information we track for each IP address to determine which channel
96 * to send the traffic over to the destination.
98 struct DestinationEntry
102 * Key under which this entry is in the 'destination_map' (only valid
103 * if 'heap_node != NULL').
105 struct GNUNET_HashCode key;
108 * Head of DLL of channels associated with this destination.
110 struct DestinationChannel *dt_head;
113 * Tail of DLL of channels associated with this destination.
115 struct DestinationChannel *dt_tail;
118 * Entry for this entry in the destination_heap.
120 struct GNUNET_CONTAINER_HeapNode *heap_node;
123 * #GNUNET_NO if this is a channel to an Internet-exit,
124 * #GNUNET_YES if this channel is to a service.
129 * Details about the connection (depending on is_service).
137 * The description of the service (only used for service channels).
139 struct GNUNET_HashCode service_descriptor;
142 * Peer offering the service.
144 struct GNUNET_PeerIdentity target;
146 } service_destination;
152 * Address family used (AF_INET or AF_INET6).
157 * IP address of the ultimate destination (only used for exit channels).
162 * Address if af is AF_INET.
167 * Address if af is AF_INET6.
180 * A messages we have in queue for a particular channel.
182 struct ChannelMessageQueueEntry
185 * This is a doubly-linked list.
187 struct ChannelMessageQueueEntry *next;
190 * This is a doubly-linked list.
192 struct ChannelMessageQueueEntry *prev;
195 * Number of bytes in @e msg.
200 * Message to transmit, allocated at the end of this struct.
207 * State we keep for each of our channels.
213 * Information about the channel to use, NULL if no channel
214 * is available right now.
216 struct GNUNET_CADET_Channel *channel;
219 * Active query with REGEX to locate exit.
221 struct GNUNET_REGEX_Search *search;
224 * Active transmission handle, NULL for none.
226 struct GNUNET_CADET_TransmitHandle *th;
229 * Entry for this entry in the channel_heap, NULL as long as this
230 * channel state is not fully bound.
232 struct GNUNET_CONTAINER_HeapNode *heap_node;
235 * Head of list of messages scheduled for transmission.
237 struct ChannelMessageQueueEntry *tmq_head;
240 * Tail of list of messages scheduled for transmission.
242 struct ChannelMessageQueueEntry *tmq_tail;
245 * Destination to which this channel leads. Note that
246 * this struct is NOT in the destination_map (but a
247 * local copy) and that the 'heap_node' should always
250 struct DestinationEntry destination;
253 * Addess family used for this channel on the local TUN interface.
258 * Is this channel new (#GNUNET_NO), or did we exchange messages with the
259 * other side already (#GNUNET_YES)?
264 * Length of the doubly linked 'tmq_head/tmq_tail' list.
266 unsigned int tmq_length;
269 * IPPROTO_TCP or IPPROTO_UDP once bound.
274 * IP address of the source on our end, initially uninitialized.
279 * Address if af is AF_INET.
284 * Address if af is AF_INET6.
291 * Destination IP address used by the source on our end (this is the IP
292 * that we pick freely within the VPN's channel IP range).
297 * Address if af is AF_INET.
302 * Address if af is AF_INET6.
309 * Source port used by the sender on our end; 0 for uninitialized.
311 uint16_t source_port;
314 * Destination port used by the sender on our end; 0 for uninitialized.
316 uint16_t destination_port;
322 * Return value from #main().
324 static int global_ret;
327 * Configuration we use.
329 static const struct GNUNET_CONFIGURATION_Handle *cfg;
332 * Handle to the cadet service.
334 static struct GNUNET_CADET_Handle *cadet_handle;
337 * Map from IP address to destination information (possibly with a
338 * CADET channel handle for fast setup).
340 static struct GNUNET_CONTAINER_MultiHashMap *destination_map;
343 * Min-Heap sorted by activity time to expire old mappings.
345 static struct GNUNET_CONTAINER_Heap *destination_heap;
348 * Map from source and destination address (IP+port) to connection
349 * information (mostly with the respective CADET channel handle).
351 static struct GNUNET_CONTAINER_MultiHashMap *channel_map;
354 * Min-Heap sorted by activity time to expire old mappings; values are
355 * of type 'struct ChannelState'.
357 static struct GNUNET_CONTAINER_Heap *channel_heap;
362 static struct GNUNET_STATISTICS_Handle *stats;
365 * The handle to the VPN helper process "gnunet-helper-vpn".
367 static struct GNUNET_HELPER_Handle *helper_handle;
370 * Arguments to the vpn helper.
372 static char *vpn_argv[7];
375 * Length of the prefix of the VPN's IPv6 network.
377 static unsigned long long ipv6prefix;
380 * If there are more than this number of address-mappings, old ones
383 static unsigned long long max_destination_mappings;
386 * If there are more than this number of open channels, old ones
389 static unsigned long long max_channel_mappings;
393 * Compute the key under which we would store an entry in the
394 * #destination_map for the given IP address.
396 * @param af address family (AF_INET or AF_INET6)
397 * @param address IP address, struct in_addr or struct in6_addr
398 * @param key where to store the key
401 get_destination_key_from_ip (int af,
403 struct GNUNET_HashCode *key)
408 GNUNET_CRYPTO_hash (address,
409 sizeof (struct in_addr),
413 GNUNET_CRYPTO_hash (address,
414 sizeof (struct in6_addr),
425 * Compute the key under which we would store an entry in the
426 * channel_map for the given socket address pair.
428 * @param af address family (AF_INET or AF_INET6)
429 * @param protocol IPPROTO_TCP or IPPROTO_UDP
430 * @param source_ip sender's source IP, struct in_addr or struct in6_addr
431 * @param source_port sender's source port
432 * @param destination_ip sender's destination IP, struct in_addr or struct in6_addr
433 * @param destination_port sender's destination port
434 * @param key where to store the key
437 get_channel_key_from_ips (int af,
439 const void *source_ip,
440 uint16_t source_port,
441 const void *destination_ip,
442 uint16_t destination_port,
443 struct GNUNET_HashCode *key)
447 memset (key, 0, sizeof (struct GNUNET_HashCode));
448 /* the GNUnet hashmap only uses the first sizeof(unsigned int) of the hash,
449 so we put the ports in there (and hope for few collisions) */
451 GNUNET_memcpy (off, &source_port, sizeof (uint16_t));
452 off += sizeof (uint16_t);
453 GNUNET_memcpy (off, &destination_port, sizeof (uint16_t));
454 off += sizeof (uint16_t);
458 GNUNET_memcpy (off, source_ip, sizeof (struct in_addr));
459 off += sizeof (struct in_addr);
460 GNUNET_memcpy (off, destination_ip, sizeof (struct in_addr));
461 off += sizeof (struct in_addr);
464 GNUNET_memcpy (off, source_ip, sizeof (struct in6_addr));
465 off += sizeof (struct in6_addr);
466 GNUNET_memcpy (off, destination_ip, sizeof (struct in6_addr));
467 off += sizeof (struct in6_addr);
473 GNUNET_memcpy (off, &protocol, sizeof (uint8_t));
474 /* off += sizeof (uint8_t); */
479 * Notify the client about the result of its request.
481 * @param client client to notify
482 * @param request_id original request ID to include in response
483 * @param result_af resulting address family
484 * @param addr resulting IP address
487 send_client_reply (struct GNUNET_SERVICE_Client *client,
492 struct GNUNET_MQ_Envelope *env;
493 struct RedirectToIpResponseMessage *res;
499 rlen = sizeof (struct in_addr);
502 rlen = sizeof (struct in6_addr);
511 env = GNUNET_MQ_msg_extra (res,
513 GNUNET_MESSAGE_TYPE_VPN_CLIENT_USE_IP);
514 res->result_af = htonl (result_af);
515 res->request_id = request_id;
516 GNUNET_memcpy (&res[1],
519 GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq (client),
525 * Free resources associated with a channel state.
527 * @param ts state to free
530 free_channel_state (struct ChannelState *ts)
532 struct GNUNET_HashCode key;
533 struct ChannelMessageQueueEntry *tnq;
534 struct GNUNET_CADET_Channel *channel;
536 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
537 "Cleaning up channel state\n");
540 GNUNET_CADET_notify_transmit_ready_cancel (ts->th);
543 if (NULL != (channel = ts->channel))
546 GNUNET_CADET_channel_destroy (channel);
549 GNUNET_STATISTICS_update (stats,
550 gettext_noop ("# Active channels"),
552 while (NULL != (tnq = ts->tmq_head))
554 GNUNET_CONTAINER_DLL_remove (ts->tmq_head,
560 GNUNET_assert (0 == ts->tmq_length);
561 GNUNET_assert (NULL == ts->destination.heap_node);
562 if (NULL != ts->search)
564 GNUNET_REGEX_search_cancel (ts->search);
567 if (NULL != ts->heap_node)
569 GNUNET_CONTAINER_heap_remove_node (ts->heap_node);
570 ts->heap_node = NULL;
571 get_channel_key_from_ips (ts->af,
576 ts->destination_port,
578 GNUNET_assert (GNUNET_YES ==
579 GNUNET_CONTAINER_multihashmap_remove (channel_map,
588 * Send a message from the message queue via cadet.
590 * @param cls the `struct ChannelState` with the message queue
591 * @param size number of bytes available in @a buf
592 * @param buf where to copy the message
593 * @return number of bytes copied to @a buf
596 send_to_peer_notify_callback (void *cls, size_t size, void *buf)
598 struct ChannelState *ts = cls;
599 struct ChannelMessageQueueEntry *tnq;
606 GNUNET_assert (NULL != tnq);
607 GNUNET_assert (size >= tnq->len);
608 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
609 "Sending %u bytes via cadet channel\n",
610 (unsigned int) tnq->len);
611 GNUNET_CONTAINER_DLL_remove (ts->tmq_head,
615 GNUNET_memcpy (buf, tnq->msg, tnq->len);
618 if (NULL != (tnq = ts->tmq_head))
621 ts->th = GNUNET_CADET_notify_transmit_ready (ts->channel,
622 GNUNET_NO /* cork */,
623 GNUNET_TIME_UNIT_FOREVER_REL,
625 &send_to_peer_notify_callback,
628 GNUNET_STATISTICS_update (stats,
629 gettext_noop ("# Bytes given to cadet for transmission"),
636 * Add the given message to the given channel and trigger the
637 * transmission process.
639 * @param tnq message to queue
640 * @param ts channel to queue the message for
643 send_to_channel (struct ChannelMessageQueueEntry *tnq,
644 struct ChannelState *ts)
646 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
647 "Queueing %u bytes for transmission via cadet channel\n",
648 (unsigned int) tnq->len);
649 GNUNET_assert (NULL != ts->channel);
650 GNUNET_CONTAINER_DLL_insert_tail (ts->tmq_head,
654 if (ts->tmq_length > MAX_MESSAGE_QUEUE_SIZE)
656 struct ChannelMessageQueueEntry *dq;
659 GNUNET_assert (dq != tnq);
660 GNUNET_CONTAINER_DLL_remove (ts->tmq_head,
664 GNUNET_CADET_notify_transmit_ready_cancel (ts->th);
666 GNUNET_STATISTICS_update (stats,
667 gettext_noop ("# Bytes dropped in cadet queue (overflow)"),
673 ts->th = GNUNET_CADET_notify_transmit_ready (ts->channel,
674 GNUNET_NO /* cork */,
675 GNUNET_TIME_UNIT_FOREVER_REL,
677 &send_to_peer_notify_callback,
683 * Output destination of a channel for diagnostics.
685 * @param de destination to process
686 * @return diagnostic string describing destination
689 print_channel_destination (const struct DestinationEntry *de)
691 static char dest[256];
695 GNUNET_snprintf (dest,
698 GNUNET_i2s (&de->details.service_destination.target),
699 GNUNET_h2s (&de->details.service_destination.service_descriptor));
703 inet_ntop (de->details.exit_destination.af,
704 &de->details.exit_destination.ip,
713 * Regex has found a potential exit peer for us; consider using it.
715 * @param cls the `struct ChannelState`
716 * @param id Peer providing a regex that matches the string.
717 * @param get_path Path of the get request.
718 * @param get_path_length Lenght of @a get_path.
719 * @param put_path Path of the put request.
720 * @param put_path_length Length of the @a put_path.
723 handle_regex_result (void *cls,
724 const struct GNUNET_PeerIdentity *id,
725 const struct GNUNET_PeerIdentity *get_path,
726 unsigned int get_path_length,
727 const struct GNUNET_PeerIdentity *put_path,
728 unsigned int put_path_length)
730 struct ChannelState *ts = cls;
731 struct GNUNET_HashCode port;
733 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
734 "Exit %s found for destination %s!\n",
736 print_channel_destination (&ts->destination));
737 GNUNET_REGEX_search_cancel (ts->search);
742 /* these must match the strings used in gnunet-daemon-exit */
743 GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_IPV4_GATEWAY,
744 strlen (GNUNET_APPLICATION_PORT_IPV4_GATEWAY),
748 /* these must match the strings used in gnunet-daemon-exit */
749 GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_IPV6_GATEWAY,
750 strlen (GNUNET_APPLICATION_PORT_IPV6_GATEWAY),
757 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
758 "Creating tunnel to %s for destination %s!\n",
760 print_channel_destination (&ts->destination));
761 ts->channel = GNUNET_CADET_channel_create (cadet_handle,
765 GNUNET_CADET_OPTION_DEFAULT);
770 * Initialize the given destination entry's cadet channel.
772 * @param dt destination channel for which we need to setup a channel
773 * @param client_af address family of the address returned to the client
774 * @return channel state of the channel that was created
776 static struct ChannelState *
777 create_channel_to_destination (struct DestinationChannel *dt,
780 struct ChannelState *ts;
782 GNUNET_STATISTICS_update (stats,
783 gettext_noop ("# Cadet channels created"),
786 ts = GNUNET_new (struct ChannelState);
788 ts->destination = *dt->destination;
789 ts->destination.heap_node = NULL; /* copy is NOT in destination heap */
790 ts->destination_port = dt->destination_port;
791 if (dt->destination->is_service)
793 struct GNUNET_HashCode cadet_port;
795 GNUNET_TUN_compute_service_cadet_port (&ts->destination.details.service_destination.service_descriptor,
796 ts->destination_port,
799 = GNUNET_CADET_channel_create (cadet_handle,
801 &dt->destination->details.service_destination.target,
803 GNUNET_CADET_OPTION_DEFAULT);
804 if (NULL == ts->channel)
810 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
811 "Creating channel to peer %s offering service %s on port %u\n",
812 GNUNET_i2s (&dt->destination->details.service_destination.target),
813 GNUNET_h2s (&ts->destination.details.service_destination.service_descriptor),
814 (unsigned int) ts->destination_port);
820 switch (dt->destination->details.exit_destination.af)
824 char address[GNUNET_TUN_IPV4_REGEXLEN];
826 GNUNET_TUN_ipv4toregexsearch (&dt->destination->details.exit_destination.ip.v4,
827 dt->destination_port,
829 GNUNET_asprintf (&policy,
831 GNUNET_APPLICATION_TYPE_EXIT_REGEX_PREFIX,
837 char address[GNUNET_TUN_IPV6_REGEXLEN];
839 GNUNET_TUN_ipv6toregexsearch (&dt->destination->details.exit_destination.ip.v6,
840 dt->destination_port,
842 GNUNET_asprintf (&policy,
844 GNUNET_APPLICATION_TYPE_EXIT_REGEX_PREFIX,
853 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
854 "Requesting connect by string: %s\n",
856 ts->search = GNUNET_REGEX_search (cfg,
858 &handle_regex_result,
860 GNUNET_free (policy);
867 * We have too many active channels. Clean up the oldest channel.
869 * @param except channel that must NOT be cleaned up, even if it is the oldest
872 expire_channel (struct ChannelState *except)
874 struct ChannelState *ts;
876 ts = GNUNET_CONTAINER_heap_peek (channel_heap);
877 GNUNET_assert (NULL != ts);
879 return; /* can't do this */
880 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
881 "Tearing down expired channel to %s\n",
882 print_channel_destination (&except->destination));
883 free_channel_state (ts);
888 * Route a packet via cadet to the given destination.
890 * @param destination description of the destination
891 * @param af address family on this end (AF_INET or AF_INET6)
892 * @param protocol IPPROTO_TCP or IPPROTO_UDP or IPPROTO_ICMP or IPPROTO_ICMPV6
893 * @param source_ip source IP used by the sender (struct in_addr or struct in6_addr)
894 * @param destination_ip destination IP used by the sender (struct in_addr or struct in6_addr)
895 * @param payload payload of the packet after the IP header
896 * @param payload_length number of bytes in @a payload
899 route_packet (struct DestinationEntry *destination,
902 const void *source_ip,
903 const void *destination_ip,
905 size_t payload_length)
907 struct GNUNET_HashCode key;
908 struct ChannelState *ts;
909 struct ChannelMessageQueueEntry *tnq;
912 const struct GNUNET_TUN_UdpHeader *udp;
913 const struct GNUNET_TUN_TcpHeader *tcp;
914 const struct GNUNET_TUN_IcmpHeader *icmp;
915 struct DestinationChannel *dt;
916 uint16_t source_port;
917 uint16_t destination_port;
923 if (payload_length < sizeof (struct GNUNET_TUN_UdpHeader))
929 tcp = NULL; /* make compiler happy */
930 icmp = NULL; /* make compiler happy */
932 if (udp->len < sizeof (struct GNUNET_TUN_UdpHeader))
937 source_port = ntohs (udp->source_port);
938 destination_port = ntohs (udp->destination_port);
939 get_channel_key_from_ips (af,
950 if (payload_length < sizeof (struct GNUNET_TUN_TcpHeader))
956 udp = NULL; /* make compiler happy */
957 icmp = NULL; /* make compiler happy */
959 if (tcp->off * 4 < sizeof (struct GNUNET_TUN_TcpHeader))
964 source_port = ntohs (tcp->source_port);
965 destination_port = ntohs (tcp->destination_port);
966 get_channel_key_from_ips (af,
978 if ( (AF_INET == af) ^ (protocol == IPPROTO_ICMP) )
983 if (payload_length < sizeof (struct GNUNET_TUN_IcmpHeader))
989 tcp = NULL; /* make compiler happy */
990 udp = NULL; /* make compiler happy */
993 destination_port = 0;
994 get_channel_key_from_ips (af,
1004 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1005 _("Protocol %u not supported, dropping\n"),
1006 (unsigned int) protocol);
1010 if (! destination->is_service)
1012 switch (destination->details.exit_destination.af)
1015 alen = sizeof (struct in_addr);
1018 alen = sizeof (struct in6_addr);
1025 char sbuf[INET6_ADDRSTRLEN];
1026 char dbuf[INET6_ADDRSTRLEN];
1027 char xbuf[INET6_ADDRSTRLEN];
1029 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1030 "Routing %s packet from [%s]:%u -> [%s]:%u to destination [%s]:%u\n",
1031 (protocol == IPPROTO_TCP) ? "TCP" : "UDP",
1042 inet_ntop (destination->details.exit_destination.af,
1043 &destination->details.exit_destination.ip,
1044 xbuf, sizeof (xbuf)),
1047 for (dt = destination->dt_head; NULL != dt; dt = dt->next)
1048 if (dt->destination_port == destination_port)
1054 char sbuf[INET6_ADDRSTRLEN];
1055 char dbuf[INET6_ADDRSTRLEN];
1057 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1058 "Routing %s packet from [%s]:%u -> [%s]:%u to service %s at peer %s\n",
1059 (protocol == IPPROTO_TCP) ? "TCP" : "UDP",
1070 GNUNET_h2s (&destination->details.service_destination.service_descriptor),
1071 GNUNET_i2s (&destination->details.service_destination.target));
1073 for (dt = destination->dt_head; NULL != dt; dt = dt->next)
1074 if (dt->destination_port == destination_port)
1079 dt = GNUNET_new (struct DestinationChannel);
1080 dt->destination = destination;
1081 GNUNET_CONTAINER_DLL_insert (destination->dt_head,
1082 destination->dt_tail,
1084 dt->destination_port = destination_port;
1087 /* see if we have an existing channel for this destination */
1088 ts = GNUNET_CONTAINER_multihashmap_get (channel_map,
1092 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1093 "Creating new channel for key %s\n",
1095 /* need to either use the existing channel from the destination (if still
1096 available) or create a fresh one */
1097 ts = create_channel_to_destination (dt,
1101 /* now bind existing "unbound" channel to our IP/port tuple */
1102 ts->protocol = protocol;
1106 ts->source_ip.v4 = * (const struct in_addr *) source_ip;
1107 ts->destination_ip.v4 = * (const struct in_addr *) destination_ip;
1111 ts->source_ip.v6 = * (const struct in6_addr *) source_ip;
1112 ts->destination_ip.v6 = * (const struct in6_addr *) destination_ip;
1114 ts->source_port = source_port;
1115 ts->destination_port = destination_port;
1116 ts->heap_node = GNUNET_CONTAINER_heap_insert (channel_heap,
1118 GNUNET_TIME_absolute_get ().abs_value_us);
1119 GNUNET_assert (GNUNET_YES ==
1120 GNUNET_CONTAINER_multihashmap_put (channel_map,
1123 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1124 GNUNET_STATISTICS_update (stats,
1125 gettext_noop ("# Active channels"),
1127 while (GNUNET_CONTAINER_multihashmap_size (channel_map) > max_channel_mappings)
1128 expire_channel (ts);
1132 GNUNET_CONTAINER_heap_update_cost (ts->heap_node,
1133 GNUNET_TIME_absolute_get ().abs_value_us);
1135 if (NULL == ts->channel)
1137 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1138 "Packet dropped, channel to %s not yet ready (%s)\n",
1139 print_channel_destination (&ts->destination),
1140 (NULL == ts->search)
1141 ? "EXIT search failed"
1142 : "EXIT search active");
1143 GNUNET_STATISTICS_update (stats,
1144 gettext_noop ("# Packets dropped (channel not yet online)"),
1150 /* send via channel */
1154 if (destination->is_service)
1156 struct GNUNET_EXIT_UdpServiceMessage *usm;
1158 mlen = sizeof (struct GNUNET_EXIT_UdpServiceMessage) +
1159 payload_length - sizeof (struct GNUNET_TUN_UdpHeader);
1160 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1165 tnq = GNUNET_malloc (sizeof (struct ChannelMessageQueueEntry) + mlen);
1168 usm = (struct GNUNET_EXIT_UdpServiceMessage *) &tnq[1];
1169 usm->header.size = htons ((uint16_t) mlen);
1170 usm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_UDP_TO_SERVICE);
1171 /* if the source port is below 32000, we assume it has a special
1172 meaning; if not, we pick a random port (this is a heuristic) */
1173 usm->source_port = (ntohs (udp->source_port) < 32000) ? udp->source_port : 0;
1174 usm->destination_port = udp->destination_port;
1175 GNUNET_memcpy (&usm[1],
1177 payload_length - sizeof (struct GNUNET_TUN_UdpHeader));
1181 struct GNUNET_EXIT_UdpInternetMessage *uim;
1182 struct in_addr *ip4dst;
1183 struct in6_addr *ip6dst;
1186 mlen = sizeof (struct GNUNET_EXIT_UdpInternetMessage) +
1187 alen + payload_length - sizeof (struct GNUNET_TUN_UdpHeader);
1188 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1193 tnq = GNUNET_malloc (sizeof (struct ChannelMessageQueueEntry) + mlen);
1196 uim = (struct GNUNET_EXIT_UdpInternetMessage *) &tnq[1];
1197 uim->header.size = htons ((uint16_t) mlen);
1198 uim->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_UDP_TO_INTERNET);
1199 uim->af = htonl (destination->details.exit_destination.af);
1200 uim->source_port = (ntohs (udp->source_port) < 32000) ? udp->source_port : 0;
1201 uim->destination_port = udp->destination_port;
1202 switch (destination->details.exit_destination.af)
1205 ip4dst = (struct in_addr *) &uim[1];
1206 *ip4dst = destination->details.exit_destination.ip.v4;
1207 payload = &ip4dst[1];
1210 ip6dst = (struct in6_addr *) &uim[1];
1211 *ip6dst = destination->details.exit_destination.ip.v6;
1212 payload = &ip6dst[1];
1217 GNUNET_memcpy (payload,
1219 payload_length - sizeof (struct GNUNET_TUN_UdpHeader));
1223 if (GNUNET_NO == ts->is_established)
1225 if (destination->is_service)
1227 struct GNUNET_EXIT_TcpServiceStartMessage *tsm;
1229 mlen = sizeof (struct GNUNET_EXIT_TcpServiceStartMessage) +
1230 payload_length - sizeof (struct GNUNET_TUN_TcpHeader);
1231 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1236 tnq = GNUNET_malloc (sizeof (struct ChannelMessageQueueEntry) + mlen);
1239 tsm = (struct GNUNET_EXIT_TcpServiceStartMessage *) &tnq[1];
1240 tsm->header.size = htons ((uint16_t) mlen);
1241 tsm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_TO_SERVICE_START);
1242 tsm->reserved = htonl (0);
1243 tsm->tcp_header = *tcp;
1244 GNUNET_memcpy (&tsm[1],
1246 payload_length - sizeof (struct GNUNET_TUN_TcpHeader));
1250 struct GNUNET_EXIT_TcpInternetStartMessage *tim;
1251 struct in_addr *ip4dst;
1252 struct in6_addr *ip6dst;
1255 mlen = sizeof (struct GNUNET_EXIT_TcpInternetStartMessage) +
1256 alen + payload_length - sizeof (struct GNUNET_TUN_TcpHeader);
1257 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1262 tnq = GNUNET_malloc (sizeof (struct ChannelMessageQueueEntry) + mlen);
1265 tim = (struct GNUNET_EXIT_TcpInternetStartMessage *) &tnq[1];
1266 tim->header.size = htons ((uint16_t) mlen);
1267 tim->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_TO_INTERNET_START);
1268 tim->af = htonl (destination->details.exit_destination.af);
1269 tim->tcp_header = *tcp;
1270 switch (destination->details.exit_destination.af)
1273 ip4dst = (struct in_addr *) &tim[1];
1274 *ip4dst = destination->details.exit_destination.ip.v4;
1275 payload = &ip4dst[1];
1278 ip6dst = (struct in6_addr *) &tim[1];
1279 *ip6dst = destination->details.exit_destination.ip.v6;
1280 payload = &ip6dst[1];
1285 GNUNET_memcpy (payload,
1287 payload_length - sizeof (struct GNUNET_TUN_TcpHeader));
1292 struct GNUNET_EXIT_TcpDataMessage *tdm;
1294 mlen = sizeof (struct GNUNET_EXIT_TcpDataMessage) +
1295 payload_length - sizeof (struct GNUNET_TUN_TcpHeader);
1296 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1301 tnq = GNUNET_malloc (sizeof (struct ChannelMessageQueueEntry) + mlen);
1304 tdm = (struct GNUNET_EXIT_TcpDataMessage *) &tnq[1];
1305 tdm->header.size = htons ((uint16_t) mlen);
1306 tdm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_DATA_TO_EXIT);
1307 tdm->reserved = htonl (0);
1308 tdm->tcp_header = *tcp;
1309 GNUNET_memcpy (&tdm[1],
1311 payload_length - sizeof (struct GNUNET_TUN_TcpHeader));
1315 case IPPROTO_ICMPV6:
1316 if (destination->is_service)
1318 struct GNUNET_EXIT_IcmpServiceMessage *ism;
1320 mlen = sizeof (struct GNUNET_EXIT_IcmpServiceMessage) +
1321 payload_length - sizeof (struct GNUNET_TUN_IcmpHeader);
1322 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1327 tnq = GNUNET_malloc (sizeof (struct ChannelMessageQueueEntry) + mlen);
1329 ism = (struct GNUNET_EXIT_IcmpServiceMessage *) &tnq[1];
1330 ism->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_SERVICE);
1331 ism->af = htonl (af); /* need to tell destination ICMP protocol family! */
1332 ism->icmp_header = *icmp;
1333 /* ICMP protocol translation will be done by the receiver (as we don't know
1334 the target AF); however, we still need to possibly discard the payload
1335 depending on the ICMP type */
1341 case GNUNET_TUN_ICMPTYPE_ECHO_REPLY:
1342 case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST:
1344 case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE:
1345 case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH:
1346 case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED:
1347 /* throw away ICMP payload, won't be useful for the other side anyway */
1348 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1351 GNUNET_STATISTICS_update (stats,
1352 gettext_noop ("# ICMPv4 packets dropped (not allowed)"),
1356 /* end of AF_INET */
1361 case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE:
1362 case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG:
1363 case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED:
1364 case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM:
1365 /* throw away ICMP payload, won't be useful for the other side anyway */
1366 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1368 case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST:
1369 case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY:
1372 GNUNET_STATISTICS_update (stats,
1373 gettext_noop ("# ICMPv6 packets dropped (not allowed)"),
1377 /* end of AF_INET6 */
1384 /* update length calculations, as payload_length may have changed */
1385 mlen = sizeof (struct GNUNET_EXIT_IcmpServiceMessage) +
1386 alen + payload_length - sizeof (struct GNUNET_TUN_IcmpHeader);
1388 ism->header.size = htons ((uint16_t) mlen);
1389 /* finally, copy payload (if there is any left...) */
1390 GNUNET_memcpy (&ism[1],
1392 payload_length - sizeof (struct GNUNET_TUN_IcmpHeader));
1396 struct GNUNET_EXIT_IcmpInternetMessage *iim;
1397 struct in_addr *ip4dst;
1398 struct in6_addr *ip6dst;
1401 mlen = sizeof (struct GNUNET_EXIT_IcmpInternetMessage) +
1402 alen + payload_length - sizeof (struct GNUNET_TUN_IcmpHeader);
1403 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1408 tnq = GNUNET_malloc (sizeof (struct ChannelMessageQueueEntry) + mlen);
1410 iim = (struct GNUNET_EXIT_IcmpInternetMessage *) &tnq[1];
1411 iim->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_INTERNET);
1412 iim->icmp_header = *icmp;
1413 /* Perform ICMP protocol-translation (depending on destination AF and source AF)
1414 and throw away ICMP payload depending on ICMP message type */
1420 case GNUNET_TUN_ICMPTYPE_ECHO_REPLY:
1421 if (destination->details.exit_destination.af == AF_INET6)
1422 iim->icmp_header.type = GNUNET_TUN_ICMPTYPE6_ECHO_REPLY;
1424 case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST:
1425 if (destination->details.exit_destination.af == AF_INET6)
1426 iim->icmp_header.type = GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST;
1428 case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE:
1429 if (destination->details.exit_destination.af == AF_INET6)
1430 iim->icmp_header.type = GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE;
1431 /* throw away IP-payload, exit will have to make it up anyway */
1432 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1434 case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED:
1435 if (destination->details.exit_destination.af == AF_INET6)
1436 iim->icmp_header.type = GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED;
1437 /* throw away IP-payload, exit will have to make it up anyway */
1438 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1440 case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH:
1441 if (destination->details.exit_destination.af == AF_INET6)
1443 GNUNET_STATISTICS_update (stats,
1444 gettext_noop ("# ICMPv4 packets dropped (impossible PT to v6)"),
1449 /* throw away IP-payload, exit will have to make it up anyway */
1450 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1453 GNUNET_STATISTICS_update (stats,
1454 gettext_noop ("# ICMPv4 packets dropped (type not allowed)"),
1459 /* end of AF_INET */
1464 case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE:
1465 if (destination->details.exit_destination.af == AF_INET6)
1466 iim->icmp_header.type = GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE;
1467 /* throw away IP-payload, exit will have to make it up anyway */
1468 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1470 case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED:
1471 if (destination->details.exit_destination.af == AF_INET)
1472 iim->icmp_header.type = GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED;
1473 /* throw away IP-payload, exit will have to make it up anyway */
1474 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1476 case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG:
1477 if (destination->details.exit_destination.af == AF_INET)
1479 GNUNET_STATISTICS_update (stats,
1480 gettext_noop ("# ICMPv6 packets dropped (impossible PT to v4)"),
1485 /* throw away IP-payload, exit will have to make it up anyway */
1486 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1488 case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM:
1489 if (destination->details.exit_destination.af == AF_INET)
1491 GNUNET_STATISTICS_update (stats,
1492 gettext_noop ("# ICMPv6 packets dropped (impossible PT to v4)"),
1497 /* throw away IP-payload, exit will have to make it up anyway */
1498 payload_length = sizeof (struct GNUNET_TUN_IcmpHeader);
1500 case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST:
1501 if (destination->details.exit_destination.af == AF_INET)
1502 iim->icmp_header.type = GNUNET_TUN_ICMPTYPE_ECHO_REQUEST;
1504 case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY:
1505 if (destination->details.exit_destination.af == AF_INET)
1506 iim->icmp_header.type = GNUNET_TUN_ICMPTYPE_ECHO_REPLY;
1509 GNUNET_STATISTICS_update (stats,
1510 gettext_noop ("# ICMPv6 packets dropped (type not allowed)"),
1515 /* end of AF_INET6 */
1520 /* update length calculations, as payload_length may have changed */
1521 mlen = sizeof (struct GNUNET_EXIT_IcmpInternetMessage) +
1522 alen + payload_length - sizeof (struct GNUNET_TUN_IcmpHeader);
1524 iim->header.size = htons ((uint16_t) mlen);
1526 /* need to tell destination ICMP protocol family! */
1527 iim->af = htonl (destination->details.exit_destination.af);
1528 switch (destination->details.exit_destination.af)
1531 ip4dst = (struct in_addr *) &iim[1];
1532 *ip4dst = destination->details.exit_destination.ip.v4;
1533 payload = &ip4dst[1];
1536 ip6dst = (struct in6_addr *) &iim[1];
1537 *ip6dst = destination->details.exit_destination.ip.v6;
1538 payload = &ip6dst[1];
1543 GNUNET_memcpy (payload,
1545 payload_length - sizeof (struct GNUNET_TUN_IcmpHeader));
1549 /* not supported above, how can we get here !? */
1553 ts->is_established = GNUNET_YES;
1554 send_to_channel (tnq, ts);
1559 * Receive packets from the helper-process (someone send to the local
1560 * virtual channel interface). Find the destination mapping, and if it
1561 * exists, identify the correct CADET channel (or possibly create it)
1562 * and forward the packet.
1564 * @param cls closure, NULL
1565 * @param client NULL
1566 * @param message message we got from the client (VPN channel interface)
1569 message_token (void *cls,
1571 const struct GNUNET_MessageHeader *message)
1573 const struct GNUNET_TUN_Layer2PacketHeader *tun;
1575 struct GNUNET_HashCode key;
1576 struct DestinationEntry *de;
1578 GNUNET_STATISTICS_update (stats,
1579 gettext_noop ("# Packets received from TUN interface"),
1581 mlen = ntohs (message->size);
1582 if ( (ntohs (message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) ||
1583 (mlen < sizeof (struct GNUNET_MessageHeader) + sizeof (struct GNUNET_TUN_Layer2PacketHeader)) )
1588 tun = (const struct GNUNET_TUN_Layer2PacketHeader *) &message[1];
1589 mlen -= (sizeof (struct GNUNET_MessageHeader) + sizeof (struct GNUNET_TUN_Layer2PacketHeader));
1590 switch (ntohs (tun->proto))
1594 const struct GNUNET_TUN_IPv6Header *pkt6;
1596 if (mlen < sizeof (struct GNUNET_TUN_IPv6Header))
1602 pkt6 = (const struct GNUNET_TUN_IPv6Header *) &tun[1];
1603 get_destination_key_from_ip (AF_INET6,
1604 &pkt6->destination_address,
1606 de = GNUNET_CONTAINER_multihashmap_get (destination_map, &key);
1609 char buf[INET6_ADDRSTRLEN];
1611 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1612 _("Packet received for unmapped destination `%s' (dropping it)\n"),
1613 inet_ntop (AF_INET6,
1614 &pkt6->destination_address,
1622 &pkt6->source_address,
1623 &pkt6->destination_address,
1625 mlen - sizeof (struct GNUNET_TUN_IPv6Header));
1630 struct GNUNET_TUN_IPv4Header *pkt4;
1632 if (mlen < sizeof (struct GNUNET_TUN_IPv4Header))
1638 pkt4 = (struct GNUNET_TUN_IPv4Header *) &tun[1];
1639 get_destination_key_from_ip (AF_INET,
1640 &pkt4->destination_address,
1642 de = GNUNET_CONTAINER_multihashmap_get (destination_map, &key);
1645 char buf[INET_ADDRSTRLEN];
1647 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1648 _("Packet received for unmapped destination `%s' (dropping it)\n"),
1650 &pkt4->destination_address,
1655 if (pkt4->header_length * 4 != sizeof (struct GNUNET_TUN_IPv4Header))
1657 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1658 _("Received IPv4 packet with options (dropping it)\n"));
1664 &pkt4->source_address,
1665 &pkt4->destination_address,
1667 mlen - sizeof (struct GNUNET_TUN_IPv4Header));
1671 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1672 _("Received packet of unknown protocol %d from TUN (dropping it)\n"),
1673 (unsigned int) ntohs (tun->proto));
1681 * Synthesize a plausible ICMP payload for an ICMP error
1682 * response on the given channel.
1684 * @param ts channel information
1685 * @param ipp IPv4 header to fill in (ICMP payload)
1686 * @param udp "UDP" header to fill in (ICMP payload); might actually
1687 * also be the first 8 bytes of the TCP header
1690 make_up_icmpv4_payload (struct ChannelState *ts,
1691 struct GNUNET_TUN_IPv4Header *ipp,
1692 struct GNUNET_TUN_UdpHeader *udp)
1694 GNUNET_TUN_initialize_ipv4_header (ipp,
1696 sizeof (struct GNUNET_TUN_TcpHeader),
1698 &ts->destination_ip.v4);
1699 udp->source_port = htons (ts->source_port);
1700 udp->destination_port = htons (ts->destination_port);
1701 udp->len = htons (0);
1702 udp->crc = htons (0);
1707 * Synthesize a plausible ICMP payload for an ICMP error
1708 * response on the given channel.
1710 * @param ts channel information
1711 * @param ipp IPv6 header to fill in (ICMP payload)
1712 * @param udp "UDP" header to fill in (ICMP payload); might actually
1713 * also be the first 8 bytes of the TCP header
1716 make_up_icmpv6_payload (struct ChannelState *ts,
1717 struct GNUNET_TUN_IPv6Header *ipp,
1718 struct GNUNET_TUN_UdpHeader *udp)
1720 GNUNET_TUN_initialize_ipv6_header (ipp,
1722 sizeof (struct GNUNET_TUN_TcpHeader),
1724 &ts->destination_ip.v6);
1725 udp->source_port = htons (ts->source_port);
1726 udp->destination_port = htons (ts->destination_port);
1727 udp->len = htons (0);
1728 udp->crc = htons (0);
1733 * We got an ICMP packet back from the CADET channel. Pass it on to the
1734 * local virtual interface via the helper.
1736 * @param cls closure, NULL
1737 * @param channel connection to the other end
1738 * @param channel_ctx pointer to our 'struct ChannelState *'
1739 * @param message the actual message
1740 * @return #GNUNET_OK to keep the connection open,
1741 * #GNUNET_SYSERR to close it (signal serious error)
1744 receive_icmp_back (void *cls,
1745 struct GNUNET_CADET_Channel *channel,
1747 const struct GNUNET_MessageHeader *message)
1749 struct ChannelState *ts = *channel_ctx;
1750 const struct GNUNET_EXIT_IcmpToVPNMessage *i2v;
1753 GNUNET_STATISTICS_update (stats,
1754 gettext_noop ("# ICMP packets received from cadet"),
1756 mlen = ntohs (message->size);
1757 if (mlen < sizeof (struct GNUNET_EXIT_IcmpToVPNMessage))
1759 GNUNET_break_op (0);
1760 return GNUNET_SYSERR;
1762 if (NULL == ts->heap_node)
1764 GNUNET_break_op (0);
1765 return GNUNET_SYSERR;
1767 if (AF_UNSPEC == ts->af)
1769 GNUNET_break_op (0);
1770 return GNUNET_SYSERR;
1772 i2v = (const struct GNUNET_EXIT_IcmpToVPNMessage *) message;
1773 mlen -= sizeof (struct GNUNET_EXIT_IcmpToVPNMessage);
1775 char sbuf[INET6_ADDRSTRLEN];
1776 char dbuf[INET6_ADDRSTRLEN];
1778 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1779 "Received ICMP packet from cadet, sending %u bytes from %s -> %s via TUN\n",
1780 (unsigned int) mlen,
1781 inet_ntop (ts->af, &ts->destination_ip, sbuf, sizeof (sbuf)),
1782 inet_ntop (ts->af, &ts->source_ip, dbuf, sizeof (dbuf)));
1788 size_t size = sizeof (struct GNUNET_TUN_IPv4Header)
1789 + sizeof (struct GNUNET_TUN_IcmpHeader)
1790 + sizeof (struct GNUNET_MessageHeader) +
1791 sizeof (struct GNUNET_TUN_Layer2PacketHeader) +
1794 /* reserve some extra space in case we have an ICMP type here where
1795 we will need to make up the payload ourselves */
1796 char buf[size + sizeof (struct GNUNET_TUN_IPv4Header) + 8] GNUNET_ALIGN;
1797 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
1798 struct GNUNET_TUN_Layer2PacketHeader *tun = (struct GNUNET_TUN_Layer2PacketHeader*) &msg[1];
1799 struct GNUNET_TUN_IPv4Header *ipv4 = (struct GNUNET_TUN_IPv4Header *) &tun[1];
1800 struct GNUNET_TUN_IcmpHeader *icmp = (struct GNUNET_TUN_IcmpHeader *) &ipv4[1];
1801 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1802 tun->flags = htons (0);
1803 tun->proto = htons (ETH_P_IPV4);
1804 GNUNET_TUN_initialize_ipv4_header (ipv4,
1806 sizeof (struct GNUNET_TUN_IcmpHeader) + mlen,
1807 &ts->destination_ip.v4,
1809 *icmp = i2v->icmp_header;
1810 GNUNET_memcpy (&icmp[1],
1813 /* For some ICMP types, we need to adjust (make up) the payload here.
1814 Also, depending on the AF used on the other side, we have to
1815 do ICMP PT (translate ICMP types) */
1816 switch (ntohl (i2v->af))
1821 case GNUNET_TUN_ICMPTYPE_ECHO_REPLY:
1822 case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST:
1824 case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE:
1825 case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH:
1826 case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED:
1828 struct GNUNET_TUN_IPv4Header *ipp = (struct GNUNET_TUN_IPv4Header *) &icmp[1];
1829 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1];
1833 /* sender did not strip ICMP payload? */
1834 GNUNET_break_op (0);
1835 return GNUNET_SYSERR;
1837 size += sizeof (struct GNUNET_TUN_IPv4Header) + 8;
1838 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
1839 make_up_icmpv4_payload (ts, ipp, udp);
1843 GNUNET_break_op (0);
1844 GNUNET_STATISTICS_update (stats,
1845 gettext_noop ("# ICMPv4 packets dropped (type not allowed)"),
1847 return GNUNET_SYSERR;
1852 /* ICMP PT 6-to-4 and possibly making up payloads */
1855 case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE:
1856 icmp->type = GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE;
1858 struct GNUNET_TUN_IPv4Header *ipp = (struct GNUNET_TUN_IPv4Header *) &icmp[1];
1859 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1];
1863 /* sender did not strip ICMP payload? */
1864 GNUNET_break_op (0);
1865 return GNUNET_SYSERR;
1867 size += sizeof (struct GNUNET_TUN_IPv4Header) + 8;
1868 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
1869 make_up_icmpv4_payload (ts, ipp, udp);
1872 case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED:
1873 icmp->type = GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED;
1875 struct GNUNET_TUN_IPv4Header *ipp = (struct GNUNET_TUN_IPv4Header *) &icmp[1];
1876 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1];
1880 /* sender did not strip ICMP payload? */
1881 GNUNET_break_op (0);
1882 return GNUNET_SYSERR;
1884 size += sizeof (struct GNUNET_TUN_IPv4Header) + 8;
1885 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
1886 make_up_icmpv4_payload (ts, ipp, udp);
1889 case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG:
1890 case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM:
1891 GNUNET_STATISTICS_update (stats,
1892 gettext_noop ("# ICMPv6 packets dropped (impossible PT to v4)"),
1895 case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST:
1896 icmp->type = GNUNET_TUN_ICMPTYPE_ECHO_REQUEST;
1898 case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY:
1899 icmp->type = GNUNET_TUN_ICMPTYPE_ECHO_REPLY;
1902 GNUNET_break_op (0);
1903 GNUNET_STATISTICS_update (stats,
1904 gettext_noop ("# ICMPv6 packets dropped (type not allowed)"),
1906 return GNUNET_SYSERR;
1911 GNUNET_break_op (0);
1912 return GNUNET_SYSERR;
1914 msg->size = htons (size);
1915 GNUNET_TUN_calculate_icmp_checksum (icmp,
1918 (void) GNUNET_HELPER_send (helper_handle,
1927 size_t size = sizeof (struct GNUNET_TUN_IPv6Header)
1928 + sizeof (struct GNUNET_TUN_IcmpHeader)
1929 + sizeof (struct GNUNET_MessageHeader) +
1930 sizeof (struct GNUNET_TUN_Layer2PacketHeader) +
1933 char buf[size + sizeof (struct GNUNET_TUN_IPv6Header) + 8] GNUNET_ALIGN;
1934 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
1935 struct GNUNET_TUN_Layer2PacketHeader *tun = (struct GNUNET_TUN_Layer2PacketHeader*) &msg[1];
1936 struct GNUNET_TUN_IPv6Header *ipv6 = (struct GNUNET_TUN_IPv6Header *) &tun[1];
1937 struct GNUNET_TUN_IcmpHeader *icmp = (struct GNUNET_TUN_IcmpHeader *) &ipv6[1];
1938 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1939 tun->flags = htons (0);
1940 tun->proto = htons (ETH_P_IPV6);
1941 GNUNET_TUN_initialize_ipv6_header (ipv6,
1943 sizeof (struct GNUNET_TUN_IcmpHeader) + mlen,
1944 &ts->destination_ip.v6,
1946 *icmp = i2v->icmp_header;
1947 GNUNET_memcpy (&icmp[1],
1951 /* For some ICMP types, we need to adjust (make up) the payload here.
1952 Also, depending on the AF used on the other side, we have to
1953 do ICMP PT (translate ICMP types) */
1954 switch (ntohl (i2v->af))
1957 /* ICMP PT 4-to-6 and possibly making up payloads */
1960 case GNUNET_TUN_ICMPTYPE_ECHO_REPLY:
1961 icmp->type = GNUNET_TUN_ICMPTYPE6_ECHO_REPLY;
1963 case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST:
1964 icmp->type = GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST;
1966 case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE:
1967 icmp->type = GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE;
1969 struct GNUNET_TUN_IPv6Header *ipp = (struct GNUNET_TUN_IPv6Header *) &icmp[1];
1970 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1];
1974 /* sender did not strip ICMP payload? */
1975 GNUNET_break_op (0);
1976 return GNUNET_SYSERR;
1978 size += sizeof (struct GNUNET_TUN_IPv6Header) + 8;
1979 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
1980 make_up_icmpv6_payload (ts, ipp, udp);
1983 case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED:
1984 icmp->type = GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED;
1986 struct GNUNET_TUN_IPv6Header *ipp = (struct GNUNET_TUN_IPv6Header *) &icmp[1];
1987 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1];
1991 /* sender did not strip ICMP payload? */
1992 GNUNET_break_op (0);
1993 return GNUNET_SYSERR;
1995 size += sizeof (struct GNUNET_TUN_IPv6Header) + 8;
1996 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
1997 make_up_icmpv6_payload (ts, ipp, udp);
2000 case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH:
2001 GNUNET_STATISTICS_update (stats,
2002 gettext_noop ("# ICMPv4 packets dropped (impossible PT to v6)"),
2006 GNUNET_break_op (0);
2007 GNUNET_STATISTICS_update (stats,
2008 gettext_noop ("# ICMPv4 packets dropped (type not allowed)"),
2010 return GNUNET_SYSERR;
2017 case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE:
2018 case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED:
2019 case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG:
2020 case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM:
2022 struct GNUNET_TUN_IPv6Header *ipp = (struct GNUNET_TUN_IPv6Header *) &icmp[1];
2023 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1];
2027 /* sender did not strip ICMP payload? */
2028 GNUNET_break_op (0);
2029 return GNUNET_SYSERR;
2031 size += sizeof (struct GNUNET_TUN_IPv6Header) + 8;
2032 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
2033 make_up_icmpv6_payload (ts, ipp, udp);
2036 case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST:
2039 GNUNET_break_op (0);
2040 GNUNET_STATISTICS_update (stats,
2041 gettext_noop ("# ICMPv6 packets dropped (type not allowed)"),
2043 return GNUNET_SYSERR;
2048 GNUNET_break_op (0);
2049 return GNUNET_SYSERR;
2051 msg->size = htons (size);
2052 GNUNET_TUN_calculate_icmp_checksum (icmp,
2054 (void) GNUNET_HELPER_send (helper_handle,
2064 GNUNET_CONTAINER_heap_update_cost (ts->heap_node,
2065 GNUNET_TIME_absolute_get ().abs_value_us);
2066 GNUNET_CADET_receive_done (channel);
2072 * We got a UDP packet back from the CADET channel. Pass it on to the
2073 * local virtual interface via the helper.
2075 * @param cls closure, NULL
2076 * @param channel connection to the other end
2077 * @param channel_ctx pointer to our 'struct ChannelState *'
2078 * @param message the actual message
2079 * @return #GNUNET_OK to keep the connection open,
2080 * #GNUNET_SYSERR to close it (signal serious error)
2083 receive_udp_back (void *cls,
2084 struct GNUNET_CADET_Channel *channel,
2086 const struct GNUNET_MessageHeader *message)
2088 struct ChannelState *ts = *channel_ctx;
2089 const struct GNUNET_EXIT_UdpReplyMessage *reply;
2092 GNUNET_STATISTICS_update (stats,
2093 gettext_noop ("# UDP packets received from cadet"),
2095 mlen = ntohs (message->size);
2096 if (mlen < sizeof (struct GNUNET_EXIT_UdpReplyMessage))
2098 GNUNET_break_op (0);
2099 return GNUNET_SYSERR;
2101 if (NULL == ts->heap_node)
2103 GNUNET_break_op (0);
2104 return GNUNET_SYSERR;
2106 if (AF_UNSPEC == ts->af)
2108 GNUNET_break_op (0);
2109 return GNUNET_SYSERR;
2111 reply = (const struct GNUNET_EXIT_UdpReplyMessage *) message;
2112 mlen -= sizeof (struct GNUNET_EXIT_UdpReplyMessage);
2114 char sbuf[INET6_ADDRSTRLEN];
2115 char dbuf[INET6_ADDRSTRLEN];
2117 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2118 "Received UDP reply from cadet, sending %u bytes from [%s]:%u -> [%s]:%u via TUN\n",
2119 (unsigned int) mlen,
2120 inet_ntop (ts->af, &ts->destination_ip, sbuf, sizeof (sbuf)),
2121 ts->destination_port,
2122 inet_ntop (ts->af, &ts->source_ip, dbuf, sizeof (dbuf)),
2129 size_t size = sizeof (struct GNUNET_TUN_IPv4Header)
2130 + sizeof (struct GNUNET_TUN_UdpHeader)
2131 + sizeof (struct GNUNET_MessageHeader) +
2132 sizeof (struct GNUNET_TUN_Layer2PacketHeader) +
2135 char buf[size] GNUNET_ALIGN;
2136 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
2137 struct GNUNET_TUN_Layer2PacketHeader *tun = (struct GNUNET_TUN_Layer2PacketHeader*) &msg[1];
2138 struct GNUNET_TUN_IPv4Header *ipv4 = (struct GNUNET_TUN_IPv4Header *) &tun[1];
2139 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipv4[1];
2140 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
2141 msg->size = htons (size);
2142 tun->flags = htons (0);
2143 tun->proto = htons (ETH_P_IPV4);
2144 GNUNET_TUN_initialize_ipv4_header (ipv4,
2146 sizeof (struct GNUNET_TUN_UdpHeader) + mlen,
2147 &ts->destination_ip.v4,
2149 if (0 == ntohs (reply->source_port))
2150 udp->source_port = htons (ts->destination_port);
2152 udp->source_port = reply->source_port;
2153 if (0 == ntohs (reply->destination_port))
2154 udp->destination_port = htons (ts->source_port);
2156 udp->destination_port = reply->destination_port;
2157 udp->len = htons (mlen + sizeof (struct GNUNET_TUN_UdpHeader));
2158 GNUNET_TUN_calculate_udp4_checksum (ipv4,
2162 GNUNET_memcpy (&udp[1],
2165 (void) GNUNET_HELPER_send (helper_handle,
2174 size_t size = sizeof (struct GNUNET_TUN_IPv6Header)
2175 + sizeof (struct GNUNET_TUN_UdpHeader)
2176 + sizeof (struct GNUNET_MessageHeader) +
2177 sizeof (struct GNUNET_TUN_Layer2PacketHeader) +
2180 char buf[size] GNUNET_ALIGN;
2181 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
2182 struct GNUNET_TUN_Layer2PacketHeader *tun = (struct GNUNET_TUN_Layer2PacketHeader*) &msg[1];
2183 struct GNUNET_TUN_IPv6Header *ipv6 = (struct GNUNET_TUN_IPv6Header *) &tun[1];
2184 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipv6[1];
2185 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
2186 msg->size = htons (size);
2187 tun->flags = htons (0);
2188 tun->proto = htons (ETH_P_IPV6);
2189 GNUNET_TUN_initialize_ipv6_header (ipv6,
2191 sizeof (struct GNUNET_TUN_UdpHeader) + mlen,
2192 &ts->destination_ip.v6,
2194 if (0 == ntohs (reply->source_port))
2195 udp->source_port = htons (ts->destination_port);
2197 udp->source_port = reply->source_port;
2198 if (0 == ntohs (reply->destination_port))
2199 udp->destination_port = htons (ts->source_port);
2201 udp->destination_port = reply->destination_port;
2202 udp->len = htons (mlen + sizeof (struct GNUNET_TUN_UdpHeader));
2203 GNUNET_TUN_calculate_udp6_checksum (ipv6,
2206 GNUNET_memcpy (&udp[1],
2209 (void) GNUNET_HELPER_send (helper_handle,
2219 GNUNET_CONTAINER_heap_update_cost (ts->heap_node,
2220 GNUNET_TIME_absolute_get ().abs_value_us);
2221 GNUNET_CADET_receive_done (channel);
2227 * We got a TCP packet back from the CADET channel. Pass it on to the
2228 * local virtual interface via the helper.
2230 * @param cls closure, NULL
2231 * @param channel connection to the other end
2232 * @param channel_ctx pointer to our `struct ChannelState *`
2233 * @param message the actual message
2234 * @return #GNUNET_OK to keep the connection open,
2235 * #GNUNET_SYSERR to close it (signal serious error)
2238 receive_tcp_back (void *cls,
2239 struct GNUNET_CADET_Channel *channel,
2241 const struct GNUNET_MessageHeader *message)
2243 struct ChannelState *ts = *channel_ctx;
2244 const struct GNUNET_EXIT_TcpDataMessage *data;
2247 GNUNET_STATISTICS_update (stats,
2248 gettext_noop ("# TCP packets received from cadet"),
2250 mlen = ntohs (message->size);
2251 if (mlen < sizeof (struct GNUNET_EXIT_TcpDataMessage))
2253 GNUNET_break_op (0);
2254 return GNUNET_SYSERR;
2256 if (NULL == ts->heap_node)
2258 GNUNET_break_op (0);
2259 return GNUNET_SYSERR;
2261 data = (const struct GNUNET_EXIT_TcpDataMessage *) message;
2262 mlen -= sizeof (struct GNUNET_EXIT_TcpDataMessage);
2264 char sbuf[INET6_ADDRSTRLEN];
2265 char dbuf[INET6_ADDRSTRLEN];
2267 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2268 "Received TCP reply from cadet, sending %u bytes from [%s]:%u -> [%s]:%u via TUN\n",
2269 (unsigned int) mlen,
2270 inet_ntop (ts->af, &ts->destination_ip, sbuf, sizeof (sbuf)),
2271 ts->destination_port,
2272 inet_ntop (ts->af, &ts->source_ip, dbuf, sizeof (dbuf)),
2275 if (data->tcp_header.off * 4 < sizeof (struct GNUNET_TUN_TcpHeader))
2277 GNUNET_break_op (0);
2278 return GNUNET_SYSERR;
2284 size_t size = sizeof (struct GNUNET_TUN_IPv4Header)
2285 + sizeof (struct GNUNET_TUN_TcpHeader)
2286 + sizeof (struct GNUNET_MessageHeader) +
2287 sizeof (struct GNUNET_TUN_Layer2PacketHeader) +
2290 char buf[size] GNUNET_ALIGN;
2291 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
2292 struct GNUNET_TUN_Layer2PacketHeader *tun = (struct GNUNET_TUN_Layer2PacketHeader*) &msg[1];
2293 struct GNUNET_TUN_IPv4Header *ipv4 = (struct GNUNET_TUN_IPv4Header *) &tun[1];
2294 struct GNUNET_TUN_TcpHeader *tcp = (struct GNUNET_TUN_TcpHeader *) &ipv4[1];
2295 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
2296 msg->size = htons (size);
2297 tun->flags = htons (0);
2298 tun->proto = htons (ETH_P_IPV4);
2299 GNUNET_TUN_initialize_ipv4_header (ipv4,
2301 sizeof (struct GNUNET_TUN_TcpHeader) + mlen,
2302 &ts->destination_ip.v4,
2304 *tcp = data->tcp_header;
2305 tcp->source_port = htons (ts->destination_port);
2306 tcp->destination_port = htons (ts->source_port);
2307 GNUNET_TUN_calculate_tcp4_checksum (ipv4,
2311 GNUNET_memcpy (&tcp[1],
2314 (void) GNUNET_HELPER_send (helper_handle,
2323 size_t size = sizeof (struct GNUNET_TUN_IPv6Header)
2324 + sizeof (struct GNUNET_TUN_TcpHeader)
2325 + sizeof (struct GNUNET_MessageHeader) +
2326 sizeof (struct GNUNET_TUN_Layer2PacketHeader) +
2329 char buf[size] GNUNET_ALIGN;
2330 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
2331 struct GNUNET_TUN_Layer2PacketHeader *tun = (struct GNUNET_TUN_Layer2PacketHeader*) &msg[1];
2332 struct GNUNET_TUN_IPv6Header *ipv6 = (struct GNUNET_TUN_IPv6Header *) &tun[1];
2333 struct GNUNET_TUN_TcpHeader *tcp = (struct GNUNET_TUN_TcpHeader *) &ipv6[1];
2334 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
2335 msg->size = htons (size);
2336 tun->flags = htons (0);
2337 tun->proto = htons (ETH_P_IPV6);
2338 GNUNET_TUN_initialize_ipv6_header (ipv6,
2340 sizeof (struct GNUNET_TUN_TcpHeader) + mlen,
2341 &ts->destination_ip.v6,
2343 *tcp = data->tcp_header;
2344 tcp->source_port = htons (ts->destination_port);
2345 tcp->destination_port = htons (ts->source_port);
2346 GNUNET_TUN_calculate_tcp6_checksum (ipv6,
2350 GNUNET_memcpy (&tcp[1],
2353 (void) GNUNET_HELPER_send (helper_handle,
2361 GNUNET_CONTAINER_heap_update_cost (ts->heap_node,
2362 GNUNET_TIME_absolute_get ().abs_value_us);
2363 GNUNET_CADET_receive_done (channel);
2369 * Allocate an IPv4 address from the range of the channel
2370 * for a new redirection.
2372 * @param v4 where to store the address
2373 * @return #GNUNET_OK on success,
2374 * #GNUNET_SYSERR on error
2377 allocate_v4_address (struct in_addr *v4)
2379 const char *ipv4addr = vpn_argv[4];
2380 const char *ipv4mask = vpn_argv[5];
2381 struct in_addr addr;
2382 struct in_addr mask;
2384 struct GNUNET_HashCode key;
2387 GNUNET_assert (1 == inet_pton (AF_INET, ipv4addr, &addr));
2388 GNUNET_assert (1 == inet_pton (AF_INET, ipv4mask, &mask));
2389 /* Given 192.168.0.1/255.255.0.0, we want a mask
2390 of '192.168.255.255', thus: */
2391 mask.s_addr = addr.s_addr | ~mask.s_addr;
2398 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2399 _("Failed to find unallocated IPv4 address in VPN's range\n"));
2400 return GNUNET_SYSERR;
2402 /* Pick random IPv4 address within the subnet, except 'addr' or 'mask' itself */
2403 rnd.s_addr = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2405 v4->s_addr = (addr.s_addr | rnd.s_addr) & mask.s_addr;
2406 get_destination_key_from_ip (AF_INET,
2410 while ( (GNUNET_YES ==
2411 GNUNET_CONTAINER_multihashmap_contains (destination_map,
2413 (v4->s_addr == addr.s_addr) ||
2414 (v4->s_addr == mask.s_addr) );
2420 * Allocate an IPv6 address from the range of the channel
2421 * for a new redirection.
2423 * @param v6 where to store the address
2424 * @return #GNUNET_OK on success,
2425 * #GNUNET_SYSERR on error
2428 allocate_v6_address (struct in6_addr *v6)
2430 const char *ipv6addr = vpn_argv[2];
2431 struct in6_addr addr;
2432 struct in6_addr mask;
2433 struct in6_addr rnd;
2435 struct GNUNET_HashCode key;
2438 GNUNET_assert (1 == inet_pton (AF_INET6, ipv6addr, &addr));
2439 GNUNET_assert (ipv6prefix < 128);
2440 /* Given ABCD::/96, we want a mask of 'ABCD::FFFF:FFFF,
2443 for (i=127;i>=ipv6prefix;i--)
2444 mask.s6_addr[i / 8] |= (1 << (i % 8));
2446 /* Pick random IPv6 address within the subnet, except 'addr' or 'mask' itself */
2453 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2454 _("Failed to find unallocated IPv6 address in VPN's range\n"));
2455 return GNUNET_SYSERR;
2460 rnd.s6_addr[i] = (unsigned char) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2463 = (addr.s6_addr[i] | rnd.s6_addr[i]) & mask.s6_addr[i];
2465 get_destination_key_from_ip (AF_INET6,
2469 while ( (GNUNET_YES ==
2470 GNUNET_CONTAINER_multihashmap_contains (destination_map,
2474 sizeof (struct in6_addr))) ||
2477 sizeof (struct in6_addr))) );
2483 * Free resources occupied by a destination entry.
2485 * @param de entry to free
2488 free_destination_entry (struct DestinationEntry *de)
2490 struct DestinationChannel *dt;
2492 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2493 "Cleaning up destination entry `%s'\n",
2494 print_channel_destination (de));
2495 GNUNET_STATISTICS_update (stats,
2496 gettext_noop ("# Active destinations"),
2498 while (NULL != (dt = de->dt_head))
2500 GNUNET_CONTAINER_DLL_remove (de->dt_head,
2505 if (NULL != de->heap_node)
2507 GNUNET_CONTAINER_heap_remove_node (de->heap_node);
2508 de->heap_node = NULL;
2509 GNUNET_assert (GNUNET_YES ==
2510 GNUNET_CONTAINER_multihashmap_remove (destination_map,
2519 * We have too many active destinations. Clean up the oldest destination.
2521 * @param except destination that must NOT be cleaned up, even if it is the oldest
2524 expire_destination (struct DestinationEntry *except)
2526 struct DestinationEntry *de;
2528 de = GNUNET_CONTAINER_heap_peek (destination_heap);
2529 GNUNET_assert (NULL != de);
2531 return; /* can't do this */
2532 free_destination_entry (de);
2537 * Allocate an IP address for the response.
2539 * @param result_af desired address family; set to the actual
2540 * address family; can initially be AF_UNSPEC if there
2541 * is no preference; will be set to AF_UNSPEC if the
2543 * @param addr set to either v4 or v6 depending on which
2544 * storage location was used; set to NULL if allocation failed
2545 * @param v4 storage space for an IPv4 address
2546 * @param v6 storage space for an IPv6 address
2547 * @return #GNUNET_OK normally, #GNUNET_SYSERR if `* result_af` was
2548 * an unsupported address family (not AF_INET, AF_INET6 or AF_UNSPEC)
2551 allocate_response_ip (int *result_af,
2554 struct in6_addr *v6)
2561 allocate_v4_address (v4))
2562 *result_af = AF_UNSPEC;
2568 allocate_v6_address (v6))
2569 *result_af = AF_UNSPEC;
2575 allocate_v4_address (v4))
2578 *result_af = AF_INET;
2580 else if (GNUNET_OK ==
2581 allocate_v6_address (v6))
2584 *result_af = AF_INET6;
2589 return GNUNET_SYSERR;
2596 * A client asks us to setup a redirection via some exit node to a
2597 * particular IP. Check if @a msg is well-formed.
2600 * @param cls client requesting client
2601 * @param msg redirection request
2602 * @return #GNUNET_OK if @a msg is well-formed
2605 check_client_redirect_to_ip (void *cls,
2606 const struct RedirectToIpRequestMessage *msg)
2611 alen = ntohs (msg->header.size) - sizeof (struct RedirectToIpRequestMessage);
2612 addr_af = (int) htonl (msg->addr_af);
2616 if (alen != sizeof (struct in_addr))
2619 return GNUNET_SYSERR;
2623 if (alen != sizeof (struct in6_addr))
2626 return GNUNET_SYSERR;
2631 return GNUNET_SYSERR;
2638 * A client asks us to setup a redirection via some exit node to a
2639 * particular IP. Setup the redirection and give the client the
2642 * @param cls client requesting client
2643 * @param msg redirection request
2646 handle_client_redirect_to_ip (void *cls,
2647 const struct RedirectToIpRequestMessage *msg)
2649 struct GNUNET_SERVICE_Client *client = cls;
2656 struct DestinationEntry *de;
2657 struct GNUNET_HashCode key;
2659 alen = ntohs (msg->header.size) - sizeof (struct RedirectToIpRequestMessage);
2660 addr_af = (int) htonl (msg->addr_af);
2661 /* allocate response IP */
2662 result_af = (int) htonl (msg->result_af);
2663 if (GNUNET_OK != allocate_response_ip (&result_af,
2667 GNUNET_SERVICE_client_drop (client);
2670 /* send reply with our IP address */
2671 send_client_reply (client,
2675 if (result_af == AF_UNSPEC)
2677 /* failure, we're done */
2678 GNUNET_SERVICE_client_continue (client);
2683 char sbuf[INET6_ADDRSTRLEN];
2684 char dbuf[INET6_ADDRSTRLEN];
2686 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2687 "Allocated address %s for redirection via exit to %s\n",
2688 inet_ntop (result_af,
2698 /* setup destination record */
2699 de = GNUNET_new (struct DestinationEntry);
2700 de->is_service = GNUNET_NO;
2701 de->details.exit_destination.af = addr_af;
2702 GNUNET_memcpy (&de->details.exit_destination.ip,
2705 get_destination_key_from_ip (result_af,
2709 GNUNET_assert (GNUNET_OK ==
2710 GNUNET_CONTAINER_multihashmap_put (destination_map,
2713 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
2714 de->heap_node = GNUNET_CONTAINER_heap_insert (destination_heap,
2716 GNUNET_TIME_absolute_ntoh (msg->expiration_time).abs_value_us);
2717 GNUNET_STATISTICS_update (stats,
2718 gettext_noop ("# Active destinations"),
2720 while (GNUNET_CONTAINER_multihashmap_size (destination_map) > max_destination_mappings)
2721 expire_destination (de);
2722 GNUNET_SERVICE_client_continue (client);
2727 * A client asks us to setup a redirection to a particular peer
2728 * offering a service. Setup the redirection and give the client the
2731 * @param cls requesting client
2732 * @param msg redirection request
2735 handle_client_redirect_to_service (void *cls,
2736 const struct RedirectToServiceRequestMessage *msg)
2738 struct GNUNET_SERVICE_Client *client = cls;
2743 struct DestinationEntry *de;
2744 struct GNUNET_HashCode key;
2745 struct DestinationChannel *dt;
2747 /* allocate response IP */
2748 result_af = (int) htonl (msg->result_af);
2750 allocate_response_ip (&result_af,
2756 GNUNET_SERVICE_client_drop (client);
2759 send_client_reply (client,
2763 if (result_af == AF_UNSPEC)
2765 /* failure, we're done */
2766 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2767 _("Failed to allocate IP address for new destination\n"));
2768 GNUNET_SERVICE_client_continue (client);
2773 char sbuf[INET6_ADDRSTRLEN];
2775 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2776 "Allocated address %s for redirection to service %s on peer %s\n",
2777 inet_ntop (result_af,
2781 GNUNET_h2s (&msg->service_descriptor),
2782 GNUNET_i2s (&msg->target));
2785 /* setup destination record */
2786 de = GNUNET_new (struct DestinationEntry);
2787 de->is_service = GNUNET_YES;
2788 de->details.service_destination.target = msg->target;
2789 de->details.service_destination.service_descriptor = msg->service_descriptor;
2790 get_destination_key_from_ip (result_af,
2794 GNUNET_assert (GNUNET_OK ==
2795 GNUNET_CONTAINER_multihashmap_put (destination_map,
2798 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
2800 = GNUNET_CONTAINER_heap_insert (destination_heap,
2802 GNUNET_TIME_absolute_ntoh (msg->expiration_time).abs_value_us);
2803 while (GNUNET_CONTAINER_multihashmap_size (destination_map) > max_destination_mappings)
2804 expire_destination (de);
2806 dt = GNUNET_new (struct DestinationChannel);
2807 dt->destination = de;
2808 GNUNET_CONTAINER_DLL_insert (de->dt_head,
2812 GNUNET_SERVICE_client_continue (client);
2817 * Function called whenever a channel is destroyed. Should clean up
2818 * any associated state.
2820 * @param cls closure (set from #GNUNET_CADET_connect)
2821 * @param channel connection to the other end (henceforth invalid)
2822 * @param channel_ctx place where local state associated
2823 * with the channel is stored (our `struct ChannelState`)
2826 channel_cleaner (void *cls,
2827 const struct GNUNET_CADET_Channel *channel,
2830 struct ChannelState *ts = channel_ctx;
2832 ts->channel = NULL; /* we must not call GNUNET_CADET_channel_destroy() anymore */
2833 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2834 "CADET notified us about death of channel to `%s'\n",
2835 print_channel_destination (&ts->destination));
2836 free_channel_state (ts);
2841 * Free memory occupied by an entry in the destination map.
2845 * @param value a `struct DestinationEntry *`
2846 * @return #GNUNET_OK (continue to iterate)
2849 cleanup_destination (void *cls,
2850 const struct GNUNET_HashCode *key,
2853 struct DestinationEntry *de = value;
2855 free_destination_entry (de);
2861 * Free memory occupied by an entry in the channel map.
2865 * @param value a `struct ChannelState *`
2866 * @return #GNUNET_OK (continue to iterate)
2869 cleanup_channel (void *cls,
2870 const struct GNUNET_HashCode *key,
2873 struct ChannelState *ts = value;
2875 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2876 "Tearing down channel to `%s' during cleanup\n",
2877 print_channel_destination (&ts->destination));
2878 free_channel_state (ts);
2884 * Function scheduled as very last function, cleans up after us
2893 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2894 "VPN is shutting down\n");
2895 if (NULL != destination_map)
2897 GNUNET_CONTAINER_multihashmap_iterate (destination_map,
2898 &cleanup_destination,
2900 GNUNET_CONTAINER_multihashmap_destroy (destination_map);
2901 destination_map = NULL;
2903 if (NULL != destination_heap)
2905 GNUNET_CONTAINER_heap_destroy (destination_heap);
2906 destination_heap = NULL;
2908 if (NULL != channel_map)
2910 GNUNET_CONTAINER_multihashmap_iterate (channel_map,
2913 GNUNET_CONTAINER_multihashmap_destroy (channel_map);
2916 if (NULL != channel_heap)
2918 GNUNET_CONTAINER_heap_destroy (channel_heap);
2919 channel_heap = NULL;
2921 if (NULL != cadet_handle)
2923 GNUNET_CADET_disconnect (cadet_handle);
2924 cadet_handle = NULL;
2926 if (NULL != helper_handle)
2928 GNUNET_HELPER_kill (helper_handle, GNUNET_NO);
2929 GNUNET_HELPER_wait (helper_handle);
2930 helper_handle = NULL;
2934 GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
2938 GNUNET_free_non_null (vpn_argv[i]);
2943 * Callback called when a client connects to the service.
2945 * @param cls closure for the service
2946 * @param c the new client that connected to the service
2947 * @param mq the message queue used to send messages to the client
2951 client_connect_cb (void *cls,
2952 struct GNUNET_SERVICE_Client *c,
2953 struct GNUNET_MQ_Handle *mq)
2960 * Callback called when a client disconnected from the service
2962 * @param cls closure for the service
2963 * @param c the client that disconnected
2964 * @param internal_cls should be equal to @a c
2967 client_disconnect_cb (void *cls,
2968 struct GNUNET_SERVICE_Client *c,
2971 GNUNET_assert (c == internal_cls);
2976 * Main function that will be run by the scheduler.
2978 * @param cls closure
2979 * @param cfg_ configuration
2980 * @param service the initialized service
2984 const struct GNUNET_CONFIGURATION_Handle *cfg_,
2985 struct GNUNET_SERVICE_Handle *service)
2987 static const struct GNUNET_CADET_MessageHandler cadet_handlers[] = {
2988 { &receive_udp_back, GNUNET_MESSAGE_TYPE_VPN_UDP_REPLY, 0},
2989 { &receive_tcp_back, GNUNET_MESSAGE_TYPE_VPN_TCP_DATA_TO_VPN, 0},
2990 { &receive_icmp_back, GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_VPN, 0},
3002 binary = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-vpn");
3005 GNUNET_OS_check_helper_binary (binary,
3007 "-d gnunet-vpn - - 169.1.3.3.7 255.255.255.0")) //ipv4 only please!
3009 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3010 "`%s' is not SUID, refusing to run.\n",
3011 "gnunet-helper-vpn");
3012 GNUNET_free (binary);
3014 /* we won't "really" exit here, as the 'service' is still running;
3015 however, as no handlers are registered, the service won't do
3019 GNUNET_free (binary);
3021 stats = GNUNET_STATISTICS_create ("vpn", cfg);
3023 GNUNET_CONFIGURATION_get_value_number (cfg,
3026 &max_destination_mappings))
3027 max_destination_mappings = 200;
3029 GNUNET_CONFIGURATION_get_value_number (cfg,
3032 &max_channel_mappings))
3033 max_channel_mappings = 200;
3035 destination_map = GNUNET_CONTAINER_multihashmap_create (max_destination_mappings * 2, GNUNET_NO);
3036 destination_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
3037 channel_map = GNUNET_CONTAINER_multihashmap_create (max_channel_mappings * 2, GNUNET_NO);
3038 channel_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
3041 vpn_argv[0] = GNUNET_strdup ("vpn-gnunet");
3042 if (GNUNET_SYSERR ==
3043 GNUNET_CONFIGURATION_get_value_string (cfg, "VPN", "IFNAME", &ifname))
3045 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, "VPN", "IFNAME");
3046 GNUNET_SCHEDULER_shutdown ();
3049 vpn_argv[1] = ifname;
3051 if (GNUNET_OK == GNUNET_NETWORK_test_pf (PF_INET6))
3053 if ( (GNUNET_SYSERR ==
3054 GNUNET_CONFIGURATION_get_value_string (cfg, "VPN", "IPV6ADDR",
3056 (1 != inet_pton (AF_INET6, ipv6addr, &v6))) )
3058 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "VPN", "IPV6ADDR",
3059 _("Must specify valid IPv6 address"));
3060 GNUNET_SCHEDULER_shutdown ();
3061 GNUNET_free_non_null (ipv6addr);
3064 vpn_argv[2] = ipv6addr;
3065 ipv6prefix_s = NULL;
3066 if (GNUNET_SYSERR ==
3067 GNUNET_CONFIGURATION_get_value_string (cfg, "VPN", "IPV6PREFIX",
3070 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, "VPN", "IPV6PREFIX");
3071 GNUNET_SCHEDULER_shutdown ();
3072 GNUNET_free_non_null (ipv6prefix_s);
3075 vpn_argv[3] = ipv6prefix_s;
3077 GNUNET_CONFIGURATION_get_value_number (cfg, "VPN",
3080 (ipv6prefix >= 127) )
3082 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "VPN", "IPV4MASK",
3083 _("Must specify valid IPv6 mask"));
3084 GNUNET_SCHEDULER_shutdown ();
3090 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3091 _("IPv6 support disabled as this system does not support IPv6\n"));
3092 vpn_argv[2] = GNUNET_strdup ("-");
3093 vpn_argv[3] = GNUNET_strdup ("-");
3095 if (GNUNET_OK == GNUNET_NETWORK_test_pf (PF_INET))
3098 if ( (GNUNET_SYSERR ==
3099 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV4ADDR",
3101 (1 != inet_pton (AF_INET, ipv4addr, &v4))) )
3103 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "VPN", "IPV4ADDR",
3104 _("Must specify valid IPv4 address"));
3105 GNUNET_SCHEDULER_shutdown ();
3106 GNUNET_free_non_null (ipv4addr);
3109 vpn_argv[4] = ipv4addr;
3111 if ( (GNUNET_SYSERR ==
3112 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV4MASK",
3114 (1 != inet_pton (AF_INET, ipv4mask, &v4))) )
3116 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "VPN", "IPV4MASK",
3117 _("Must specify valid IPv4 mask"));
3118 GNUNET_SCHEDULER_shutdown ();
3119 GNUNET_free_non_null (ipv4mask);
3122 vpn_argv[5] = ipv4mask;
3126 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
3127 _("IPv4 support disabled as this system does not support IPv4\n"));
3128 vpn_argv[4] = GNUNET_strdup ("-");
3129 vpn_argv[5] = GNUNET_strdup ("-");
3134 = GNUNET_CADET_connect (cfg_,
3138 // FIXME never opens ports???
3139 helper_handle = GNUNET_HELPER_start (GNUNET_NO,
3140 "gnunet-helper-vpn", vpn_argv,
3141 &message_token, NULL, NULL);
3142 GNUNET_SCHEDULER_add_shutdown (&cleanup,
3148 * Define "main" method using service macro.
3152 GNUNET_SERVICE_OPTION_NONE,
3155 &client_disconnect_cb,
3157 GNUNET_MQ_hd_var_size (client_redirect_to_ip,
3158 GNUNET_MESSAGE_TYPE_VPN_CLIENT_REDIRECT_TO_IP,
3159 struct RedirectToIpRequestMessage,
3161 GNUNET_MQ_hd_fixed_size (client_redirect_to_service,
3162 GNUNET_MESSAGE_TYPE_VPN_CLIENT_REDIRECT_TO_SERVICE,
3163 struct RedirectToServiceRequestMessage,
3165 GNUNET_MQ_handler_end ());
3168 /* end of gnunet-service-vpn.c */