2 This file is part of GNUnet.
3 (C) 2010, 2011, 2012 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
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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
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, 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 mesh
26 * @author Philipp Toelke
27 * @author Christian Grothoff
32 * - better message queue management (bounded state, drop oldest/RED?)
33 * - actually destroy "stale" tunnels once we have too many!
36 * - add back ICMP support (especially needed for IPv6)
39 * - consider moving IP-header building / checksumming code into shared library
40 * with dns/exit/vpn (libgnunettun_tcpip?)
43 #include "gnunet_util_lib.h"
44 #include "gnunet_common.h"
45 #include "gnunet_protocols.h"
46 #include "gnunet_applications.h"
47 #include "gnunet_mesh_service.h"
48 #include "gnunet_statistics_service.h"
49 #include "gnunet_constants.h"
50 #include "tcpip_tun.h"
56 * State we keep for each of our tunnels.
62 * Information we track for each IP address to determine which tunnel
63 * to send the traffic over to the destination.
65 struct DestinationEntry
69 * Key under which this entry is in the 'destination_map' (only valid
70 * if 'heap_node != NULL'.
75 * Pre-allocated tunnel for this destination, or NULL for none.
77 struct TunnelState *ts;
80 * Entry for this entry in the destination_heap.
82 struct GNUNET_CONTAINER_HeapNode *heap_node;
85 * GNUNET_NO if this is a tunnel to an Internet-exit,
86 * GNUNET_YES if this tunnel is to a service.
91 * Details about the connection (depending on is_service).
99 * The description of the service (only used for service tunnels).
101 GNUNET_HashCode service_descriptor;
104 * Peer offering the service.
106 struct GNUNET_PeerIdentity target;
108 } service_destination;
114 * Address family used (AF_INET or AF_INET6).
119 * IP address of the ultimate destination (only used for exit tunnels).
124 * Address if af is AF_INET.
129 * Address if af is AF_INET6.
142 * A messages we have in queue for a particular tunnel.
144 struct TunnelMessageQueueEntry
147 * This is a doubly-linked list.
149 struct TunnelMessageQueueEntry *next;
152 * This is a doubly-linked list.
154 struct TunnelMessageQueueEntry *prev;
157 * Number of bytes in 'msg'.
162 * Message to transmit, allocated at the end of this struct.
169 * State we keep for each of our tunnels.
174 * Information about the tunnel to use, NULL if no tunnel
175 * is available right now.
177 struct GNUNET_MESH_Tunnel *tunnel;
180 * Active transmission handle, NULL for none.
182 struct GNUNET_MESH_TransmitHandle *th;
185 * Entry for this entry in the tunnel_heap, NULL as long as this
186 * tunnel state is not fully bound.
188 struct GNUNET_CONTAINER_HeapNode *heap_node;
191 * Head of list of messages scheduled for transmission.
193 struct TunnelMessageQueueEntry *head;
196 * Tail of list of messages scheduled for transmission.
198 struct TunnelMessageQueueEntry *tail;
201 * Client that needs to be notified about the tunnel being
202 * up as soon as a peer is connected; NULL for none.
204 struct GNUNET_SERVER_Client *client;
207 * ID of the client request that caused us to setup this entry.
212 * Destination to which this tunnel leads. Note that
213 * this struct is NOT in the destination_map (but a
214 * local copy) and that the 'heap_node' should always
217 struct DestinationEntry destination;
220 * Destination entry that has a pointer to this tunnel state;
221 * NULL if this tunnel state is in the tunnel map.
223 struct DestinationEntry *destination_container;
226 * Addess family used for this tunnel on the local TUN interface.
231 * IPPROTO_TCP or IPPROTO_UDP once bound.
236 * IP address of the source on our end, initially uninitialized.
241 * Address if af is AF_INET.
246 * Address if af is AF_INET6.
253 * Destination IP address used by the source on our end (this is the IP
254 * that we pick freely within the VPN's tunnel IP range).
259 * Address if af is AF_INET.
264 * Address if af is AF_INET6.
271 * Source port used by the sender on our end; 0 for uninitialized.
273 uint16_t source_port;
276 * Destination port used by the sender on our end; 0 for uninitialized.
278 uint16_t destination_port;
284 * Configuration we use.
286 static const struct GNUNET_CONFIGURATION_Handle *cfg;
289 * Handle to the mesh service.
291 static struct GNUNET_MESH_Handle *mesh_handle;
294 * Map from IP address to destination information (possibly with a
295 * MESH tunnel handle for fast setup).
297 static struct GNUNET_CONTAINER_MultiHashMap *destination_map;
300 * Min-Heap sorted by activity time to expire old mappings.
302 static struct GNUNET_CONTAINER_Heap *destination_heap;
305 * Map from source and destination address (IP+port) to connection
306 * information (mostly with the respective MESH tunnel handle).
308 static struct GNUNET_CONTAINER_MultiHashMap *tunnel_map;
311 * Min-Heap sorted by activity time to expire old mappings; values are
312 * of type 'struct TunnelState'.
314 static struct GNUNET_CONTAINER_Heap *tunnel_heap;
319 static struct GNUNET_STATISTICS_Handle *stats;
322 * The handle to the VPN helper process "gnunet-helper-vpn".
324 static struct GNUNET_HELPER_Handle *helper_handle;
327 * Arguments to the vpn helper.
329 static char *vpn_argv[7];
332 * Length of the prefix of the VPN's IPv6 network.
334 static unsigned long long ipv6prefix;
337 * Notification context for sending replies to clients.
339 static struct GNUNET_SERVER_NotificationContext *nc;
342 * If there are more than this number of address-mappings, old ones
345 static unsigned long long max_destination_mappings;
348 * If there are more than this number of open tunnels, old ones
351 static unsigned long long max_tunnel_mappings;
355 * Compute the key under which we would store an entry in the
356 * destination_map for the given IP address.
358 * @param af address family (AF_INET or AF_INET6)
359 * @param address IP address, struct in_addr or struct in6_addr
360 * @param key where to store the key
363 get_destination_key_from_ip (int af,
365 GNUNET_HashCode *key)
370 GNUNET_CRYPTO_hash (address,
371 sizeof (struct in_addr),
375 GNUNET_CRYPTO_hash (address,
376 sizeof (struct in6_addr),
387 * Compute the key under which we would store an entry in the
388 * tunnel_map for the given socket address pair.
390 * @param af address family (AF_INET or AF_INET6)
391 * @param protocol IPPROTO_TCP or IPPROTO_UDP
392 * @param source_ip sender's source IP, struct in_addr or struct in6_addr
393 * @param source_port sender's source port
394 * @param destination_ip sender's destination IP, struct in_addr or struct in6_addr
395 * @param destination_port sender's destination port
396 * @param key where to store the key
399 get_tunnel_key_from_ips (int af,
401 const void *source_ip,
402 uint16_t source_port,
403 const void *destination_ip,
404 uint16_t destination_port,
405 GNUNET_HashCode *key)
409 memset (key, 0, sizeof (GNUNET_HashCode));
410 /* the GNUnet hashmap only uses the first sizeof(unsigned int) of the hash,
411 so we put the ports in there (and hope for few collisions) */
413 memcpy (off, &source_port, sizeof (uint16_t));
414 off += sizeof (uint16_t);
415 memcpy (off, &destination_port, sizeof (uint16_t));
416 off += sizeof (uint16_t);
420 memcpy (off, source_ip, sizeof (struct in_addr));
421 off += sizeof (struct in_addr);
422 memcpy (off, destination_ip, sizeof (struct in_addr));
423 off += sizeof (struct in_addr);
426 memcpy (off, source_ip, sizeof (struct in6_addr));
427 off += sizeof (struct in6_addr);
428 memcpy (off, destination_ip, sizeof (struct in6_addr));
429 off += sizeof (struct in6_addr);
435 memcpy (off, &protocol, sizeof (uint8_t));
436 off += sizeof (uint8_t);
441 * Notify the client about the result of its request.
443 * @param client client to notify
444 * @param request_id original request ID to include in response
445 * @param result_af resulting address family
446 * @param addr resulting IP address
449 send_client_reply (struct GNUNET_SERVER_Client *client,
454 char buf[sizeof (struct RedirectToIpResponseMessage) + sizeof (struct in6_addr)];
455 struct RedirectToIpResponseMessage *res;
461 rlen = sizeof (struct in_addr);
464 rlen = sizeof (struct in6_addr);
473 res = (struct RedirectToIpResponseMessage *) buf;
474 res->header.size = htons (sizeof (struct RedirectToIpResponseMessage) + rlen);
475 res->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_CLIENT_USE_IP);
476 res->result_af = htonl (result_af);
477 res->request_id = request_id;
478 memcpy (&res[1], addr, rlen);
479 GNUNET_SERVER_notification_context_add (nc, client);
480 GNUNET_SERVER_notification_context_unicast (nc,
488 * Method called whenever a peer has disconnected from the tunnel.
491 * @param peer peer identity the tunnel stopped working with
494 tunnel_peer_disconnect_handler (void *cls,
496 GNUNET_PeerIdentity * peer)
498 struct TunnelState *ts = cls;
500 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
501 "Peer %s disconnected from tunnel.\n",
503 GNUNET_STATISTICS_update (stats,
504 gettext_noop ("# Peers connected to mesh tunnels"),
508 GNUNET_MESH_notify_transmit_ready_cancel (ts->th);
511 if (ts->destination.is_service)
512 return; /* hope for reconnect eventually */
513 /* as we are most likely going to change the exit node now,
514 we should just destroy the tunnel entirely... */
515 GNUNET_MESH_tunnel_destroy (ts->tunnel);
520 * Method called whenever a peer has connected to the tunnel. Notifies
521 * the waiting client that the tunnel is now up.
524 * @param peer peer identity the tunnel was created to, NULL on timeout
525 * @param atsi performance data for the connection
528 tunnel_peer_connect_handler (void *cls,
529 const struct GNUNET_PeerIdentity
532 GNUNET_ATS_Information * atsi)
534 struct TunnelState *ts = cls;
536 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
537 "Peer %s connected to tunnel.\n",
539 GNUNET_STATISTICS_update (stats,
540 gettext_noop ("# Peers connected to mesh tunnels"),
542 if (NULL == ts->client)
543 return; /* nothing to do */
544 send_client_reply (ts->client,
547 &ts->destination_ip);
548 GNUNET_SERVER_client_drop (ts->client);
554 * Send a message from the message queue via mesh.
556 * @param cls the 'struct TunnelState' with the message queue
557 * @param size number of bytes available in buf
558 * @param buf where to copy the message
559 * @return number of bytes copied to buf
562 send_to_peer_notify_callback (void *cls, size_t size, void *buf)
564 struct TunnelState *ts = cls;
565 struct TunnelMessageQueueEntry *tnq;
572 GNUNET_assert (NULL != tnq);
573 GNUNET_assert (size >= tnq->len);
574 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
575 "Sending %u bytes via mesh tunnel\n",
577 GNUNET_CONTAINER_DLL_remove (ts->head,
580 memcpy (buf, tnq->msg, tnq->len);
583 if (NULL != (tnq = ts->head))
584 ts->th = GNUNET_MESH_notify_transmit_ready (ts->tunnel,
585 GNUNET_NO /* cork */,
587 GNUNET_TIME_UNIT_FOREVER_REL,
590 &send_to_peer_notify_callback,
592 GNUNET_STATISTICS_update (stats,
593 gettext_noop ("# Bytes given to mesh for transmission"),
600 * Add the given message to the given tunnel and trigger the
601 * transmission process.
603 * FIXME: bound queue length!
605 * @param tnq message to queue
606 * @param ts tunnel to queue the message for
609 send_to_tunnel (struct TunnelMessageQueueEntry *tnq,
610 struct TunnelState *ts)
612 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
613 "Queueing %u bytes for transmission via mesh tunnel\n",
615 GNUNET_CONTAINER_DLL_insert_tail (ts->head,
619 ts->th = GNUNET_MESH_notify_transmit_ready (ts->tunnel,
620 GNUNET_NO /* cork */,
622 GNUNET_TIME_UNIT_FOREVER_REL,
625 &send_to_peer_notify_callback,
631 * Initialize the given destination entry's mesh tunnel.
633 * @param de destination entry for which we need to setup a tunnel
634 * @param client client to notify on successful tunnel setup, or NULL for none
635 * @param request_id request ID to send in client notification (unused if client is NULL)
636 * @return tunnel state of the tunnel that was created
638 static struct TunnelState *
639 create_tunnel_to_destination (struct DestinationEntry *de,
640 struct GNUNET_SERVER_Client *client,
643 struct TunnelState *ts;
645 GNUNET_STATISTICS_update (stats,
646 gettext_noop ("# Mesh tunnels created"),
648 GNUNET_assert (NULL == de->ts);
649 ts = GNUNET_malloc (sizeof (struct TunnelState));
652 ts->request_id = request_id;
654 GNUNET_SERVER_client_keep (client);
656 ts->destination = *de;
657 ts->destination.heap_node = NULL; /* copy is NOT in destination heap */
659 ts->destination_container = de; /* we are referenced from de */
660 ts->af = AF_UNSPEC; /* so far, unknown */
661 ts->tunnel = GNUNET_MESH_tunnel_create (mesh_handle,
663 &tunnel_peer_connect_handler,
664 &tunnel_peer_disconnect_handler,
668 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
669 "Creating tunnel to peer %s offering service %s\n",
670 GNUNET_i2s (&de->details.service_destination.target),
671 GNUNET_h2s (&de->details.service_destination.service_descriptor));
672 GNUNET_MESH_peer_request_connect_add (ts->tunnel,
673 &de->details.service_destination.target);
677 switch (de->details.exit_destination.af)
680 GNUNET_MESH_peer_request_connect_by_type (ts->tunnel,
681 GNUNET_APPLICATION_TYPE_IPV4_GATEWAY);
682 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
683 "Creating tunnel to exit peer for %s\n",
687 GNUNET_MESH_peer_request_connect_by_type (ts->tunnel,
688 GNUNET_APPLICATION_TYPE_IPV6_GATEWAY);
689 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
690 "Creating tunnel to exit peer for %s\n",
703 * Route a packet via mesh to the given destination.
705 * @param destination description of the destination
706 * @param af address family on this end (AF_INET or AF_INET6)
707 * @param protocol IPPROTO_TCP or IPPROTO_UDP
708 * @param source_ip source IP used by the sender (struct in_addr or struct in6_addr)
709 * @param destination_ip destination IP used by the sender (struct in_addr or struct in6_addr)
710 * @param payload payload of the packet after the IP header
711 * @param payload_length number of bytes in payload
714 route_packet (struct DestinationEntry *destination,
717 const void *source_ip,
718 const void *destination_ip,
720 size_t payload_length)
723 struct TunnelState *ts;
724 struct TunnelMessageQueueEntry *tnq;
728 const struct udp_packet *udp;
729 const struct tcp_packet *tcp;
737 if (payload_length < sizeof (struct udp_packet))
744 spt = ntohs (udp->spt);
745 dpt = ntohs (udp->dpt);
746 get_tunnel_key_from_ips (af,
757 if (payload_length < sizeof (struct tcp_packet))
764 spt = ntohs (tcp->spt);
765 dpt = ntohs (tcp->dpt);
766 get_tunnel_key_from_ips (af,
776 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
777 _("Protocol %u not supported, dropping\n"),
778 (unsigned int) protocol);
781 if (! destination->is_service)
783 switch (destination->details.exit_destination.af)
786 alen = sizeof (struct in_addr);
789 alen = sizeof (struct in6_addr);
797 char sbuf[INET6_ADDRSTRLEN];
798 char dbuf[INET6_ADDRSTRLEN];
799 char xbuf[INET6_ADDRSTRLEN];
801 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
802 "Routing %s packet from %s:%u -> %s:%u to destination %s:%u\n",
803 (protocol == IPPROTO_TCP) ? "TCP" : "UDP",
804 inet_ntop (af, source_ip, sbuf, sizeof (sbuf)),
806 inet_ntop (af, destination_ip, dbuf, sizeof (dbuf)),
808 inet_ntop (destination->details.exit_destination.af,
809 &destination->details.exit_destination.ip,
810 xbuf, sizeof (xbuf)));
815 /* make compiler happy */
818 char sbuf[INET6_ADDRSTRLEN];
819 char dbuf[INET6_ADDRSTRLEN];
821 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
822 "Routing %s packet from %s:%u -> %s:%u to service %s at peer %s\n",
823 (protocol == IPPROTO_TCP) ? "TCP" : "UDP",
824 inet_ntop (af, source_ip, sbuf, sizeof (sbuf)),
826 inet_ntop (af, destination_ip, dbuf, sizeof (dbuf)),
828 GNUNET_h2s (&destination->details.service_destination.service_descriptor),
829 GNUNET_i2s (&destination->details.service_destination.target));
834 /* see if we have an existing tunnel for this destination */
835 ts = GNUNET_CONTAINER_multihashmap_get (tunnel_map,
839 /* need to either use the existing tunnel from the destination (if still
840 available) or create a fresh one */
842 if (NULL == destination->ts)
843 ts = create_tunnel_to_destination (destination, NULL, 0);
845 ts = destination->ts;
846 destination->ts = NULL;
847 ts->destination_container = NULL; /* no longer 'contained' */
848 /* now bind existing "unbound" tunnel to our IP/port tuple */
849 ts->protocol = protocol;
853 ts->source_ip.v4 = * (const struct in_addr *) source_ip;
854 ts->destination_ip.v4 = * (const struct in_addr *) destination_ip;
858 ts->source_ip.v6 = * (const struct in6_addr *) source_ip;
859 ts->destination_ip.v6 = * (const struct in6_addr *) destination_ip;
861 ts->source_port = spt;
862 ts->destination_port = dpt;
863 ts->heap_node = GNUNET_CONTAINER_heap_insert (tunnel_heap,
865 GNUNET_TIME_absolute_get ().abs_value);
866 GNUNET_assert (GNUNET_YES ==
867 GNUNET_CONTAINER_multihashmap_put (tunnel_map,
870 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
871 GNUNET_STATISTICS_update (stats,
872 gettext_noop ("# Active tunnels"),
874 /* FIXME: expire OLD tunnels if we have too many! */
879 GNUNET_CONTAINER_heap_update_cost (tunnel_heap,
881 GNUNET_TIME_absolute_get ().abs_value);
884 /* send via tunnel */
888 if (destination->is_service)
890 struct GNUNET_EXIT_UdpServiceMessage *usm;
892 mlen = sizeof (struct GNUNET_EXIT_UdpServiceMessage) +
893 payload_length - sizeof (struct udp_packet);
894 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
899 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + mlen);
900 usm = (struct GNUNET_EXIT_UdpServiceMessage *) &tnq[1];
901 usm->header.size = htons ((uint16_t) mlen);
902 usm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_UDP_TO_SERVICE);
903 /* if the source port is below 32000, we assume it has a special
904 meaning; if not, we pick a random port (this is a heuristic) */
905 usm->source_port = (ntohs (udp->spt) < 32000) ? udp->spt : 0;
906 usm->destination_port = udp->dpt;
907 usm->service_descriptor = destination->details.service_destination.service_descriptor;
910 payload_length - sizeof (struct udp_packet));
914 struct GNUNET_EXIT_UdpInternetMessage *uim;
915 struct in_addr *ip4dst;
916 struct in6_addr *ip6dst;
919 mlen = sizeof (struct GNUNET_EXIT_UdpInternetMessage) +
920 alen + payload_length - sizeof (struct udp_packet);
921 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
926 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) +
928 uim = (struct GNUNET_EXIT_UdpInternetMessage *) &tnq[1];
929 uim->header.size = htons ((uint16_t) mlen);
930 uim->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_UDP_TO_INTERNET);
931 uim->af = htonl (destination->details.exit_destination.af);
932 uim->source_port = (ntohs (udp->spt) < 32000) ? udp->spt : 0;
933 uim->destination_port = udp->dpt;
934 switch (destination->details.exit_destination.af)
937 ip4dst = (struct in_addr *) &uim[1];
938 *ip4dst = destination->details.exit_destination.ip.v4;
939 payload = &ip4dst[1];
942 ip6dst = (struct in6_addr *) &uim[1];
943 *ip6dst = destination->details.exit_destination.ip.v6;
944 payload = &ip6dst[1];
951 payload_length - sizeof (struct udp_packet));
957 if (destination->is_service)
959 struct GNUNET_EXIT_TcpServiceStartMessage *tsm;
961 mlen = sizeof (struct GNUNET_EXIT_TcpServiceStartMessage) +
962 payload_length - sizeof (struct tcp_packet);
963 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
968 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + mlen);
969 tsm = (struct GNUNET_EXIT_TcpServiceStartMessage *) &tnq[1];
970 tsm->header.size = htons ((uint16_t) mlen);
971 tsm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_TO_SERVICE_START);
972 tsm->reserved = htonl (0);
973 tsm->service_descriptor = destination->details.service_destination.service_descriptor;
974 tsm->tcp_header = *tcp;
977 payload_length - sizeof (struct tcp_packet));
981 struct GNUNET_EXIT_TcpInternetStartMessage *tim;
982 struct in_addr *ip4dst;
983 struct in6_addr *ip6dst;
986 mlen = sizeof (struct GNUNET_EXIT_TcpInternetStartMessage) +
987 alen + payload_length - sizeof (struct tcp_packet);
988 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
993 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + mlen);
994 tim = (struct GNUNET_EXIT_TcpInternetStartMessage *) &tnq[1];
995 tim->header.size = htons ((uint16_t) mlen);
996 tim->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_TO_INTERNET_START);
997 tim->af = htonl (destination->details.exit_destination.af);
998 tim->tcp_header = *tcp;
999 switch (destination->details.exit_destination.af)
1002 ip4dst = (struct in_addr *) &tim[1];
1003 *ip4dst = destination->details.exit_destination.ip.v4;
1004 payload = &ip4dst[1];
1007 ip6dst = (struct in6_addr *) &tim[1];
1008 *ip6dst = destination->details.exit_destination.ip.v6;
1009 payload = &ip6dst[1];
1016 payload_length - sizeof (struct tcp_packet));
1021 struct GNUNET_EXIT_TcpDataMessage *tdm;
1023 mlen = sizeof (struct GNUNET_EXIT_TcpDataMessage) +
1024 alen + payload_length - sizeof (struct tcp_packet);
1025 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1030 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + mlen);
1031 tdm = (struct GNUNET_EXIT_TcpDataMessage *) &tnq[1];
1032 tdm->header.size = htons ((uint16_t) mlen);
1033 tdm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_DATA);
1034 tdm->reserved = htonl (0);
1035 tdm->tcp_header = *tcp;
1038 payload_length - sizeof (struct tcp_packet));
1042 /* not supported above, how can we get here !? */
1046 send_to_tunnel (tnq, ts);
1051 * Receive packets from the helper-process (someone send to the local
1052 * virtual tunnel interface). Find the destination mapping, and if it
1053 * exists, identify the correct MESH tunnel (or possibly create it)
1054 * and forward the packet.
1056 * @param cls closure, NULL
1057 * @param client NULL
1058 * @param message message we got from the client (VPN tunnel interface)
1061 message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED,
1062 const struct GNUNET_MessageHeader *message)
1064 const struct tun_header *tun;
1066 GNUNET_HashCode key;
1067 struct DestinationEntry *de;
1069 GNUNET_STATISTICS_update (stats,
1070 gettext_noop ("# Packets received from TUN interface"),
1072 mlen = ntohs (message->size);
1073 if ( (ntohs (message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) ||
1074 (mlen < sizeof (struct GNUNET_MessageHeader) + sizeof (struct tun_header)) )
1079 tun = (const struct tun_header *) &message[1];
1080 mlen -= (sizeof (struct GNUNET_MessageHeader) + sizeof (struct tun_header));
1081 switch (ntohs (tun->proto))
1085 const struct ip6_header *pkt6;
1087 if (mlen < sizeof (struct ip6_header))
1093 pkt6 = (const struct ip6_header *) &tun[1];
1094 get_destination_key_from_ip (AF_INET6,
1095 &pkt6->destination_address,
1097 de = GNUNET_CONTAINER_multihashmap_get (destination_map, &key);
1098 /* FIXME: do we need to guard against hash collision?
1099 (if so, we need to also store the local destination IP in the
1100 destination entry and then compare here; however, the risk
1101 of collision seems minimal AND the impact is unlikely to be
1102 super-problematic as well... */
1105 char buf[INET6_ADDRSTRLEN];
1107 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1108 _("Packet received for unmapped destination `%s' (dropping it)\n"),
1109 inet_ntop (AF_INET6,
1110 &pkt6->destination_address,
1118 &pkt6->source_address,
1119 &pkt6->destination_address,
1121 mlen - sizeof (struct ip6_header));
1126 struct ip4_header *pkt4;
1128 if (mlen < sizeof (struct ip4_header))
1134 pkt4 = (struct ip4_header *) &tun[1];
1135 get_destination_key_from_ip (AF_INET,
1136 &pkt4->destination_address,
1138 de = GNUNET_CONTAINER_multihashmap_get (destination_map, &key);
1139 /* FIXME: do we need to guard against hash collision?
1140 (if so, we need to also store the local destination IP in the
1141 destination entry and then compare here; however, the risk
1142 of collision seems minimal AND the impact is unlikely to be
1143 super-problematic as well... */
1146 char buf[INET_ADDRSTRLEN];
1148 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1149 _("Packet received for unmapped destination `%s' (dropping it)\n"),
1151 &pkt4->destination_address,
1156 if (pkt4->header_length * 4 != sizeof (struct ip4_header))
1158 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1159 _("Received IPv4 packet with options (dropping it)\n"));
1165 &pkt4->source_address,
1166 &pkt4->destination_address,
1168 mlen - sizeof (struct ip4_header));
1172 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1173 _("Received packet of unknown protocol %d from TUN (dropping it)\n"),
1174 (unsigned int) ntohs (tun->proto));
1181 * We got a UDP packet back from the MESH tunnel. Pass it on to the
1182 * local virtual interface via the helper.
1184 * @param cls closure, NULL
1185 * @param tunnel connection to the other end
1186 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1187 * @param sender who sent the message
1188 * @param message the actual message
1189 * @param atsi performance data for the connection
1190 * @return GNUNET_OK to keep the connection open,
1191 * GNUNET_SYSERR to close it (signal serious error)
1194 receive_udp_back (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1195 void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender,
1196 const struct GNUNET_MessageHeader *message,
1197 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1199 struct TunnelState *ts = *tunnel_ctx;
1200 const struct GNUNET_EXIT_UdpReplyMessage *reply;
1203 GNUNET_STATISTICS_update (stats,
1204 gettext_noop ("# UDP packets received from mesh"),
1206 mlen = ntohs (message->size);
1207 if (mlen < sizeof (struct GNUNET_EXIT_UdpReplyMessage))
1209 GNUNET_break_op (0);
1210 return GNUNET_SYSERR;
1212 if (NULL == ts->heap_node)
1214 GNUNET_break_op (0);
1215 return GNUNET_SYSERR;
1217 if (AF_UNSPEC == ts->af)
1219 GNUNET_break_op (0);
1220 return GNUNET_SYSERR;
1222 reply = (const struct GNUNET_EXIT_UdpReplyMessage *) message;
1223 mlen -= sizeof (struct GNUNET_EXIT_UdpReplyMessage);
1225 char sbuf[INET6_ADDRSTRLEN];
1226 char dbuf[INET6_ADDRSTRLEN];
1228 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1229 "Received UDP reply from mesh, sending %u bytes from %s:%u -> %s:%u via TUN\n",
1230 (unsigned int) mlen,
1231 inet_ntop (ts->af, &ts->destination_ip, sbuf, sizeof (sbuf)),
1232 ts->destination_port,
1233 inet_ntop (ts->af, &ts->source_ip, dbuf, sizeof (dbuf)),
1240 size_t size = sizeof (struct ip4_header)
1241 + sizeof (struct udp_packet)
1242 + sizeof (struct GNUNET_MessageHeader) +
1243 sizeof (struct tun_header) +
1247 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
1248 struct tun_header *tun = (struct tun_header*) &msg[1];
1249 struct ip4_header *ipv4 = (struct ip4_header *) &tun[1];
1250 struct udp_packet *udp = (struct udp_packet *) &ipv4[1];
1251 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1252 msg->size = htons (size);
1253 tun->flags = htons (0);
1254 tun->proto = htons (ETH_P_IPV4);
1256 ipv4->header_length = sizeof (struct ip4_header) / 4;
1257 ipv4->diff_serv = 0;
1258 ipv4->total_length = htons (sizeof (struct ip4_header) +
1259 sizeof (struct udp_packet) +
1261 ipv4->identification = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1264 ipv4->fragmentation_offset = 0;
1266 ipv4->protocol = IPPROTO_UDP;
1268 ipv4->source_address = ts->destination_ip.v4;
1269 ipv4->destination_address = ts->source_ip.v4;
1271 GNUNET_CRYPTO_crc16_n (ipv4, sizeof (struct ip4_header));
1272 if (0 == ntohs (reply->source_port))
1273 udp->spt = htons (ts->destination_port);
1275 udp->spt = reply->source_port;
1276 if (0 == ntohs (reply->destination_port))
1277 udp->dpt = htons (ts->source_port);
1279 udp->dpt = reply->destination_port;
1280 udp->len = htons (mlen + sizeof (struct udp_packet));
1281 udp->crc = 0; // FIXME: optional, but we might want to calculate this one anyway
1285 (void) GNUNET_HELPER_send (helper_handle,
1294 size_t size = sizeof (struct ip6_header)
1295 + sizeof (struct udp_packet)
1296 + sizeof (struct GNUNET_MessageHeader) +
1297 sizeof (struct tun_header) +
1301 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
1302 struct tun_header *tun = (struct tun_header*) &msg[1];
1303 struct ip6_header *ipv6 = (struct ip6_header *) &tun[1];
1304 struct udp_packet *udp = (struct udp_packet *) &ipv6[1];
1305 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1306 msg->size = htons (size);
1307 tun->flags = htons (0);
1308 tun->proto = htons (ETH_P_IPV6);
1309 ipv6->traffic_class_h = 0;
1311 ipv6->traffic_class_l = 0;
1312 ipv6->flow_label = 0;
1313 ipv6->payload_length = htons (sizeof (struct udp_packet) + sizeof (struct ip6_header) + mlen);
1314 ipv6->next_header = IPPROTO_UDP;
1315 ipv6->hop_limit = 255;
1316 ipv6->source_address = ts->destination_ip.v6;
1317 ipv6->destination_address = ts->source_ip.v6;
1318 if (0 == ntohs (reply->source_port))
1319 udp->spt = htons (ts->destination_port);
1321 udp->spt = reply->source_port;
1322 if (0 == ntohs (reply->destination_port))
1323 udp->dpt = htons (ts->source_port);
1325 udp->dpt = reply->destination_port;
1326 udp->len = htons (mlen + sizeof (struct udp_packet));
1334 GNUNET_CRYPTO_crc16_step (sum, &ipv6->source_address,
1335 sizeof (struct in6_addr) * 2);
1336 uint32_t tmp = udp->len;
1337 sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
1338 tmp = htons (IPPROTO_UDP);
1339 sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
1340 sum = GNUNET_CRYPTO_crc16_step (sum,
1343 udp->crc = GNUNET_CRYPTO_crc16_finish (sum);
1345 (void) GNUNET_HELPER_send (helper_handle,
1355 GNUNET_CONTAINER_heap_update_cost (tunnel_heap,
1357 GNUNET_TIME_absolute_get ().abs_value);
1363 * We got a TCP packet back from the MESH tunnel. Pass it on to the
1364 * local virtual interface via the helper.
1366 * @param cls closure, NULL
1367 * @param tunnel connection to the other end
1368 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1369 * @param sender who sent the message
1370 * @param message the actual message
1371 * @param atsi performance data for the connection
1372 * @return GNUNET_OK to keep the connection open,
1373 * GNUNET_SYSERR to close it (signal serious error)
1376 receive_tcp_back (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1378 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1379 const struct GNUNET_MessageHeader *message,
1380 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1382 struct TunnelState *ts = *tunnel_ctx;
1383 const struct GNUNET_EXIT_TcpDataMessage *data;
1386 GNUNET_STATISTICS_update (stats,
1387 gettext_noop ("# TCP packets received from mesh"),
1389 mlen = ntohs (message->size);
1390 if (mlen < sizeof (struct GNUNET_EXIT_TcpDataMessage))
1392 GNUNET_break_op (0);
1393 return GNUNET_SYSERR;
1395 if (NULL == ts->heap_node)
1397 GNUNET_break_op (0);
1398 return GNUNET_SYSERR;
1400 data = (const struct GNUNET_EXIT_TcpDataMessage *) message;
1401 mlen -= sizeof (struct GNUNET_EXIT_TcpDataMessage);
1403 char sbuf[INET6_ADDRSTRLEN];
1404 char dbuf[INET6_ADDRSTRLEN];
1406 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1407 "Received TCP reply from mesh, sending %u bytes from %s:%u -> %s:%u via TUN\n",
1408 (unsigned int) mlen,
1409 inet_ntop (ts->af, &ts->destination_ip, sbuf, sizeof (sbuf)),
1410 ts->destination_port,
1411 inet_ntop (ts->af, &ts->source_ip, dbuf, sizeof (dbuf)),
1418 size_t size = sizeof (struct ip4_header)
1419 + sizeof (struct tcp_packet)
1420 + sizeof (struct GNUNET_MessageHeader) +
1421 sizeof (struct tun_header) +
1425 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
1426 struct tun_header *tun = (struct tun_header*) &msg[1];
1427 struct ip4_header *ipv4 = (struct ip4_header *) &tun[1];
1428 struct tcp_packet *tcp = (struct tcp_packet *) &ipv4[1];
1429 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1430 msg->size = htons (size);
1431 tun->flags = htons (0);
1432 tun->proto = htons (ETH_P_IPV4);
1434 ipv4->header_length = sizeof (struct ip4_header) / 4;
1435 ipv4->diff_serv = 0;
1436 ipv4->total_length = htons (sizeof (struct ip4_header) +
1437 sizeof (struct tcp_packet) +
1439 ipv4->identification = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1442 ipv4->fragmentation_offset = 0;
1444 ipv4->protocol = IPPROTO_TCP;
1446 ipv4->source_address = ts->destination_ip.v4;
1447 ipv4->destination_address = ts->source_ip.v4;
1449 GNUNET_CRYPTO_crc16_n (ipv4, sizeof (struct ip4_header));
1450 *tcp = data->tcp_header;
1451 tcp->spt = htons (ts->destination_port);
1452 tcp->dpt = htons (ts->source_port);
1461 sum = GNUNET_CRYPTO_crc16_step (sum,
1462 &ipv4->source_address,
1463 2 * sizeof (struct in_addr));
1464 tmp = htonl ((IPPROTO_TCP << 16) | (mlen + sizeof (struct tcp_packet)));
1465 sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
1466 sum = GNUNET_CRYPTO_crc16_step (sum, tcp, mlen + sizeof (struct tcp_packet));
1467 tcp->crc = GNUNET_CRYPTO_crc16_finish (sum);
1469 (void) GNUNET_HELPER_send (helper_handle,
1478 size_t size = sizeof (struct ip6_header)
1479 + sizeof (struct tcp_packet)
1480 + sizeof (struct GNUNET_MessageHeader) +
1481 sizeof (struct tun_header) +
1485 struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
1486 struct tun_header *tun = (struct tun_header*) &msg[1];
1487 struct ip6_header *ipv6 = (struct ip6_header *) &tun[1];
1488 struct tcp_packet *tcp = (struct tcp_packet *) &ipv6[1];
1489 msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1490 msg->size = htons (size);
1491 tun->flags = htons (0);
1492 tun->proto = htons (ETH_P_IPV6);
1493 ipv6->traffic_class_h = 0;
1495 ipv6->traffic_class_l = 0;
1496 ipv6->flow_label = 0;
1497 ipv6->payload_length = htons (sizeof (struct tcp_packet) + sizeof (struct ip6_header) + mlen);
1498 ipv6->next_header = IPPROTO_TCP;
1499 ipv6->hop_limit = 255;
1500 ipv6->source_address = ts->destination_ip.v6;
1501 ipv6->destination_address = ts->source_ip.v6;
1502 tcp->spt = htons (ts->destination_port);
1503 tcp->dpt = htons (ts->source_port);
1509 sum = GNUNET_CRYPTO_crc16_step (sum, &ipv6->source_address, 2 * sizeof (struct in6_addr));
1510 tmp = htonl (sizeof (struct tcp_packet) + mlen);
1511 sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
1512 tmp = htonl (IPPROTO_TCP);
1513 sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
1514 sum = GNUNET_CRYPTO_crc16_step (sum, tcp,
1515 sizeof (struct tcp_packet) + mlen);
1516 tcp->crc = GNUNET_CRYPTO_crc16_finish (sum);
1518 (void) GNUNET_HELPER_send (helper_handle,
1526 GNUNET_CONTAINER_heap_update_cost (tunnel_heap,
1528 GNUNET_TIME_absolute_get ().abs_value);
1534 * Allocate an IPv4 address from the range of the tunnel
1535 * for a new redirection.
1537 * @param v4 where to store the address
1538 * @return GNUNET_OK on success,
1539 * GNUNET_SYSERR on error
1542 allocate_v4_address (struct in_addr *v4)
1544 const char *ipv4addr = vpn_argv[4];
1545 const char *ipv4mask = vpn_argv[5];
1546 struct in_addr addr;
1547 struct in_addr mask;
1549 GNUNET_HashCode key;
1552 GNUNET_assert (1 == inet_pton (AF_INET, ipv4addr, &addr));
1553 GNUNET_assert (1 == inet_pton (AF_INET, ipv4mask, &mask));
1554 /* Given 192.168.0.1/255.255.0.0, we want a mask
1555 of '192.168.255.255', thus: */
1556 mask.s_addr = addr.s_addr | ~mask.s_addr;
1563 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1564 _("Failed to find unallocated IPv4 address in VPN's range\n"));
1565 return GNUNET_SYSERR;
1567 /* Pick random IPv4 address within the subnet, except 'addr' or 'mask' itself */
1568 rnd.s_addr = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1570 v4->s_addr = (addr.s_addr | rnd.s_addr) & mask.s_addr;
1571 get_destination_key_from_ip (AF_INET,
1575 while ( (GNUNET_YES ==
1576 GNUNET_CONTAINER_multihashmap_contains (destination_map,
1578 (v4->s_addr == addr.s_addr) ||
1579 (v4->s_addr == mask.s_addr) );
1585 * Allocate an IPv6 address from the range of the tunnel
1586 * for a new redirection.
1588 * @param v6 where to store the address
1589 * @return GNUNET_OK on success,
1590 * GNUNET_SYSERR on error
1593 allocate_v6_address (struct in6_addr *v6)
1595 const char *ipv6addr = vpn_argv[2];
1596 struct in6_addr addr;
1597 struct in6_addr mask;
1598 struct in6_addr rnd;
1600 GNUNET_HashCode key;
1603 GNUNET_assert (1 == inet_pton (AF_INET6, ipv6addr, &addr));
1604 GNUNET_assert (ipv6prefix < 128);
1605 /* Given ABCD::/96, we want a mask of 'ABCD::FFFF:FFFF,
1608 for (i=127;i>=128-ipv6prefix;i--)
1609 mask.s6_addr[i / 8] |= (1 << (i % 8));
1611 /* Pick random IPv6 address within the subnet, except 'addr' or 'mask' itself */
1618 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1619 _("Failed to find unallocated IPv6 address in VPN's range\n"));
1620 return GNUNET_SYSERR;
1625 rnd.s6_addr[i] = (unsigned char) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1628 = (addr.s6_addr[i] | rnd.s6_addr[i]) & mask.s6_addr[i];
1630 get_destination_key_from_ip (AF_INET6,
1634 while ( (GNUNET_YES ==
1635 GNUNET_CONTAINER_multihashmap_contains (destination_map,
1639 sizeof (struct in6_addr))) ||
1642 sizeof (struct in6_addr))) );
1648 * A client asks us to setup a redirection via some exit
1649 * node to a particular IP. Setup the redirection and
1650 * give the client the allocated IP.
1653 * @param client requesting client
1654 * @param message redirection request (a 'struct RedirectToIpRequestMessage')
1657 service_redirect_to_ip (void *cls GNUNET_UNUSED, struct GNUNET_SERVER_Client *client,
1658 const struct GNUNET_MessageHeader *message)
1662 const struct RedirectToIpRequestMessage *msg;
1668 struct DestinationEntry *de;
1669 GNUNET_HashCode key;
1671 /* validate and parse request */
1672 mlen = ntohs (message->size);
1673 if (mlen < sizeof (struct RedirectToIpRequestMessage))
1676 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1679 alen = mlen - sizeof (struct RedirectToIpRequestMessage);
1680 msg = (const struct RedirectToIpRequestMessage *) message;
1681 addr_af = (int) htonl (msg->addr_af);
1685 if (alen != sizeof (struct in_addr))
1688 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1693 if (alen != sizeof (struct in6_addr))
1696 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1702 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1706 /* allocate response IP */
1708 result_af = (int) htonl (msg->result_af);
1713 allocate_v4_address (&v4))
1714 result_af = AF_UNSPEC;
1720 allocate_v6_address (&v6))
1721 result_af = AF_UNSPEC;
1727 allocate_v4_address (&v4))
1730 result_af = AF_INET;
1732 else if (GNUNET_OK ==
1733 allocate_v6_address (&v6))
1736 result_af = AF_INET6;
1741 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1744 if ( (result_af == AF_UNSPEC) ||
1745 (GNUNET_NO == ntohl (msg->nac)) )
1747 /* send reply "instantly" */
1748 send_client_reply (client,
1753 if (result_af == AF_UNSPEC)
1755 /* failure, we're done */
1756 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1761 char sbuf[INET6_ADDRSTRLEN];
1762 char dbuf[INET6_ADDRSTRLEN];
1764 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1765 "Allocated address %s for redirection via exit to %s\n",
1766 inet_ntop (result_af, addr, sbuf, sizeof (sbuf)),
1768 &msg[1], dbuf, sizeof (dbuf)));
1771 /* setup destination record */
1772 de = GNUNET_malloc (sizeof (struct DestinationEntry));
1773 de->is_service = GNUNET_NO;
1774 de->details.exit_destination.af = addr_af;
1775 memcpy (&de->details.exit_destination.ip,
1778 get_destination_key_from_ip (result_af,
1782 GNUNET_assert (GNUNET_OK ==
1783 GNUNET_CONTAINER_multihashmap_put (destination_map,
1786 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
1787 de->heap_node = GNUNET_CONTAINER_heap_insert (destination_heap,
1789 GNUNET_TIME_absolute_ntoh (msg->expiration_time).abs_value);
1790 GNUNET_STATISTICS_update (stats,
1791 gettext_noop ("# Active destinations"),
1794 /* FIXME: expire OLD destinations if we have too many! */
1795 /* setup tunnel to destination */
1796 (void) create_tunnel_to_destination (de,
1797 (GNUNET_NO == ntohl (msg->nac)) ? NULL : client,
1799 GNUNET_assert (NULL != de->ts);
1801 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1806 * A client asks us to setup a redirection to a particular peer
1807 * offering a service. Setup the redirection and give the client the
1811 * @param client requesting client
1812 * @param message redirection request (a 'struct RedirectToPeerRequestMessage')
1815 service_redirect_to_service (void *cls GNUNET_UNUSED, struct GNUNET_SERVER_Client *client,
1816 const struct GNUNET_MessageHeader *message)
1818 const struct RedirectToServiceRequestMessage *msg;
1823 struct DestinationEntry *de;
1824 GNUNET_HashCode key;
1827 msg = (const struct RedirectToServiceRequestMessage *) message;
1829 /* allocate response IP */
1831 result_af = (int) htonl (msg->result_af);
1836 allocate_v4_address (&v4))
1837 result_af = AF_UNSPEC;
1843 allocate_v6_address (&v6))
1844 result_af = AF_UNSPEC;
1850 allocate_v4_address (&v4))
1853 result_af = AF_INET;
1855 else if (GNUNET_OK ==
1856 allocate_v6_address (&v6))
1859 result_af = AF_INET6;
1864 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1867 if ( (result_af == AF_UNSPEC) ||
1868 (GNUNET_NO == ntohl (msg->nac)) )
1870 /* send reply "instantly" */
1871 send_client_reply (client,
1876 if (result_af == AF_UNSPEC)
1878 /* failure, we're done */
1879 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1880 _("Failed to allocate IP address for new destination\n"));
1881 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1886 char sbuf[INET6_ADDRSTRLEN];
1888 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1889 "Allocated address %s for redirection to service %s on peer %s\n",
1890 inet_ntop (result_af, addr, sbuf, sizeof (sbuf)),
1891 GNUNET_h2s (&msg->service_descriptor),
1892 GNUNET_i2s (&msg->target));
1895 /* setup destination record */
1896 de = GNUNET_malloc (sizeof (struct DestinationEntry));
1897 de->is_service = GNUNET_YES;
1898 de->details.service_destination.service_descriptor = msg->service_descriptor;
1899 de->details.service_destination.target = msg->target;
1900 get_destination_key_from_ip (result_af,
1904 GNUNET_assert (GNUNET_OK ==
1905 GNUNET_CONTAINER_multihashmap_put (destination_map,
1908 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
1909 de->heap_node = GNUNET_CONTAINER_heap_insert (destination_heap,
1911 GNUNET_TIME_absolute_ntoh (msg->expiration_time).abs_value);
1912 /* FIXME: expire OLD destinations if we have too many! */
1913 (void) create_tunnel_to_destination (de,
1914 (GNUNET_NO == ntohl (msg->nac)) ? NULL : client,
1917 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1923 * Function called for inbound tunnels. As we don't offer
1924 * any mesh services, this function should never be called.
1926 * @param cls closure
1927 * @param tunnel new handle to the tunnel
1928 * @param initiator peer that started the tunnel
1929 * @param atsi performance information for the tunnel
1930 * @return initial tunnel context for the tunnel
1931 * (can be NULL -- that's not an error)
1934 inbound_tunnel_cb (void *cls, struct GNUNET_MESH_Tunnel *tunnel,
1935 const struct GNUNET_PeerIdentity *initiator,
1936 const struct GNUNET_ATS_Information *atsi)
1938 /* How can and why should anyone open an inbound tunnel to vpn? */
1945 * Free resources associated with a tunnel state.
1947 * @param ts state to free
1950 free_tunnel_state (struct TunnelState *ts)
1952 GNUNET_HashCode key;
1953 struct TunnelMessageQueueEntry *tnq;
1955 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1956 "Cleaning up tunnel state\n");
1957 GNUNET_STATISTICS_update (stats,
1958 gettext_noop ("# Active tunnels"),
1960 while (NULL != (tnq = ts->head))
1962 GNUNET_CONTAINER_DLL_remove (ts->head,
1967 if (NULL != ts->client)
1969 GNUNET_SERVER_client_drop (ts->client);
1974 GNUNET_MESH_notify_transmit_ready_cancel (ts->th);
1977 GNUNET_assert (NULL == ts->destination.heap_node);
1978 if (NULL != ts->tunnel)
1980 GNUNET_MESH_tunnel_destroy (ts->tunnel);
1983 if (NULL != ts->heap_node)
1985 GNUNET_CONTAINER_heap_remove_node (ts->heap_node);
1986 ts->heap_node = NULL;
1987 get_tunnel_key_from_ips (ts->af,
1991 &ts->destination_ip,
1992 ts->destination_port,
1994 GNUNET_assert (GNUNET_YES ==
1995 GNUNET_CONTAINER_multihashmap_remove (tunnel_map,
1999 if (NULL != ts->destination_container)
2001 GNUNET_assert (ts == ts->destination_container->ts);
2002 ts->destination_container->ts = NULL;
2003 ts->destination_container = NULL;
2010 * Free resources occupied by a destination entry.
2012 * @param de entry to free
2015 free_destination_entry (struct DestinationEntry *de)
2017 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2018 "Cleaning up destination entry\n");
2019 GNUNET_STATISTICS_update (stats,
2020 gettext_noop ("# Active destinations"),
2024 free_tunnel_state (de->ts);
2025 GNUNET_assert (NULL == de->ts);
2027 if (NULL != de->heap_node)
2029 GNUNET_CONTAINER_heap_remove_node (de->heap_node);
2030 de->heap_node = NULL;
2031 GNUNET_assert (GNUNET_YES ==
2032 GNUNET_CONTAINER_multihashmap_remove (destination_map,
2041 * Function called whenever an inbound tunnel is destroyed. Should clean up
2042 * any associated state.
2044 * @param cls closure (set from GNUNET_MESH_connect)
2045 * @param tunnel connection to the other end (henceforth invalid)
2046 * @param tunnel_ctx place where local state associated
2047 * with the tunnel is stored (our 'struct TunnelState')
2050 tunnel_cleaner (void *cls, const struct GNUNET_MESH_Tunnel *tunnel, void *tunnel_ctx)
2052 struct TunnelState *ts = tunnel_ctx;
2059 GNUNET_assert (ts->tunnel == tunnel);
2061 free_tunnel_state (ts);
2066 * Free memory occupied by an entry in the destination map.
2070 * @param value a 'struct DestinationEntry *'
2071 * @return GNUNET_OK (continue to iterate)
2074 cleanup_destination (void *cls,
2075 const GNUNET_HashCode *key,
2078 struct DestinationEntry *de = value;
2080 free_destination_entry (de);
2086 * Free memory occupied by an entry in the tunnel map.
2090 * @param value a 'struct TunnelState *'
2091 * @return GNUNET_OK (continue to iterate)
2094 cleanup_tunnel (void *cls,
2095 const GNUNET_HashCode *key,
2098 struct TunnelState *ts = value;
2100 free_tunnel_state (ts);
2106 * Function scheduled as very last function, cleans up after us
2112 cleanup (void *cls GNUNET_UNUSED,
2113 const struct GNUNET_SCHEDULER_TaskContext *tc)
2117 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2118 "VPN is shutting down\n");
2119 if (NULL != destination_map)
2121 GNUNET_CONTAINER_multihashmap_iterate (destination_map,
2122 &cleanup_destination,
2124 GNUNET_CONTAINER_multihashmap_destroy (destination_map);
2125 destination_map = NULL;
2127 if (NULL != destination_heap)
2129 GNUNET_CONTAINER_heap_destroy (destination_heap);
2130 destination_heap = NULL;
2132 if (NULL != tunnel_map)
2134 GNUNET_CONTAINER_multihashmap_iterate (tunnel_map,
2137 GNUNET_CONTAINER_multihashmap_destroy (tunnel_map);
2140 if (NULL != tunnel_heap)
2142 GNUNET_CONTAINER_heap_destroy (tunnel_heap);
2145 if (NULL != mesh_handle)
2147 GNUNET_MESH_disconnect (mesh_handle);
2150 if (NULL != helper_handle)
2152 GNUNET_HELPER_stop (helper_handle);
2153 helper_handle = NULL;
2157 GNUNET_SERVER_notification_context_destroy (nc);
2162 GNUNET_STATISTICS_destroy (stats, GNUNET_YES);
2166 GNUNET_free_non_null (vpn_argv[i]);
2171 * A client disconnected, clean up all references to it.
2173 * @param cls the client that disconnected
2175 * @param value a 'struct TunnelState *'
2176 * @return GNUNET_OK (continue to iterate)
2179 cleanup_tunnel_client (void *cls,
2180 const GNUNET_HashCode *key,
2183 struct GNUNET_SERVER_Client *client = cls;
2184 struct TunnelState *ts = value;
2186 if (client == ts->client)
2188 GNUNET_SERVER_client_drop (ts->client);
2196 * A client disconnected, clean up all references to it.
2198 * @param cls the client that disconnected
2200 * @param value a 'struct DestinationEntry *'
2201 * @return GNUNET_OK (continue to iterate)
2204 cleanup_destination_client (void *cls,
2205 const GNUNET_HashCode *key,
2208 struct GNUNET_SERVER_Client *client = cls;
2209 struct DestinationEntry *de = value;
2210 struct TunnelState *ts;
2212 if (NULL == (ts = de->ts))
2214 if (client == ts->client)
2216 GNUNET_SERVER_client_drop (ts->client);
2224 * A client has disconnected from us. If we are currently building
2225 * a tunnel for it, cancel the operation.
2228 * @param client handle to the client that disconnected
2231 client_disconnect (void *cls, struct GNUNET_SERVER_Client *client)
2233 if (NULL != tunnel_map)
2234 GNUNET_CONTAINER_multihashmap_iterate (tunnel_map,
2235 &cleanup_tunnel_client,
2237 if (NULL != destination_map)
2238 GNUNET_CONTAINER_multihashmap_iterate (destination_map,
2239 &cleanup_destination_client,
2245 * Main function that will be run by the scheduler.
2247 * @param cls closure
2248 * @param server the initialized server
2249 * @param cfg_ configuration
2253 struct GNUNET_SERVER_Handle *server,
2254 const struct GNUNET_CONFIGURATION_Handle *cfg_)
2256 static const struct GNUNET_SERVER_MessageHandler service_handlers[] = {
2257 /* callback, cls, type, size */
2258 {&service_redirect_to_ip, NULL, GNUNET_MESSAGE_TYPE_VPN_CLIENT_REDIRECT_TO_IP, 0},
2259 {&service_redirect_to_service, NULL,
2260 GNUNET_MESSAGE_TYPE_VPN_CLIENT_REDIRECT_TO_SERVICE,
2261 sizeof (struct RedirectToServiceRequestMessage) },
2264 static const struct GNUNET_MESH_MessageHandler mesh_handlers[] = {
2265 {receive_udp_back, GNUNET_MESSAGE_TYPE_VPN_SERVICE_UDP_BACK, 0},
2266 {receive_tcp_back, GNUNET_MESSAGE_TYPE_VPN_SERVICE_TCP_BACK, 0},
2267 {receive_udp_back, GNUNET_MESSAGE_TYPE_VPN_REMOTE_UDP_BACK, 0},
2268 {receive_tcp_back, GNUNET_MESSAGE_TYPE_VPN_REMOTE_TCP_BACK, 0},
2271 static const GNUNET_MESH_ApplicationType types[] = {
2272 GNUNET_APPLICATION_TYPE_END
2283 stats = GNUNET_STATISTICS_create ("vpn", cfg);
2285 GNUNET_CONFIGURATION_get_value_number (cfg, "vpn", "MAX_MAPPING",
2286 &max_destination_mappings))
2287 max_destination_mappings = 200;
2289 GNUNET_CONFIGURATION_get_value_number (cfg, "vpn", "MAX_TUNNELS",
2290 &max_tunnel_mappings))
2291 max_tunnel_mappings = 200;
2293 destination_map = GNUNET_CONTAINER_multihashmap_create (max_destination_mappings * 2);
2294 destination_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
2295 tunnel_map = GNUNET_CONTAINER_multihashmap_create (max_tunnel_mappings * 2);
2296 tunnel_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
2299 vpn_argv[0] = GNUNET_strdup ("vpn-gnunet");
2300 if (GNUNET_SYSERR ==
2301 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IFNAME", &ifname))
2303 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2304 "No entry 'IFNAME' in configuration!\n");
2305 GNUNET_SCHEDULER_shutdown ();
2308 vpn_argv[1] = ifname;
2309 if ( (GNUNET_SYSERR ==
2310 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV6ADDR",
2312 (1 != inet_pton (AF_INET6, ipv6addr, &v6))) )
2314 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2315 "No valid entry 'IPV6ADDR' in configuration!\n");
2316 GNUNET_SCHEDULER_shutdown ();
2319 vpn_argv[2] = ipv6addr;
2320 if (GNUNET_SYSERR ==
2321 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV6PREFIX",
2324 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2325 "No entry 'IPV6PREFIX' in configuration!\n");
2326 GNUNET_SCHEDULER_shutdown ();
2329 vpn_argv[3] = ipv6prefix_s;
2331 GNUNET_CONFIGURATION_get_value_number (cfg, "vpn",
2334 (ipv6prefix >= 127) )
2336 GNUNET_SCHEDULER_shutdown ();
2340 if ( (GNUNET_SYSERR ==
2341 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV4ADDR",
2343 (1 != inet_pton (AF_INET, ipv4addr, &v4))) )
2345 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2346 "No valid entry for 'IPV4ADDR' in configuration!\n");
2347 GNUNET_SCHEDULER_shutdown ();
2350 vpn_argv[4] = ipv4addr;
2351 if ( (GNUNET_SYSERR ==
2352 GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV4MASK",
2354 (1 != inet_pton (AF_INET, ipv4mask, &v4))) )
2356 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2357 "No valid entry 'IPV4MASK' in configuration!\n");
2358 GNUNET_SCHEDULER_shutdown ();
2361 vpn_argv[5] = ipv4mask;
2365 GNUNET_MESH_connect (cfg_, 42 /* queue length */, NULL,
2370 helper_handle = GNUNET_HELPER_start ("gnunet-helper-vpn", vpn_argv,
2371 &message_token, NULL);
2372 nc = GNUNET_SERVER_notification_context_create (server, 1);
2373 GNUNET_SERVER_add_handlers (server, service_handlers);
2374 GNUNET_SERVER_disconnect_notify (server, &client_disconnect, NULL);
2375 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
2380 * The main function of the VPN service.
2382 * @param argc number of arguments from the command line
2383 * @param argv command line arguments
2384 * @return 0 ok, 1 on error
2387 main (int argc, char *const *argv)
2389 return (GNUNET_OK ==
2390 GNUNET_SERVICE_run (argc, argv, "vpn",
2391 GNUNET_SERVICE_OPTION_NONE,
2392 &run, NULL)) ? 0 : 1;
2395 /* end of gnunet-service-vpn.c */