2 This file is part of GNUnet.
3 (C) 2010, 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
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., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file exit/gnunet-daemon-exit.c
23 * @brief tool to allow IP traffic exit from the GNUnet mesh to the Internet
24 * @author Philipp Toelke
25 * @author Christian Grothoff
31 * - which code should advertise services? the service model is right
32 * now a bit odd, especially as this code DOES the exit and knows
33 * the DNS "name", but OTOH this is clearly NOT the place to advertise
34 * the service's existence; maybe the daemon should turn into a
35 * service with an API to add local-exit services dynamically?
38 #include "gnunet_util_lib.h"
39 #include "gnunet_protocols.h"
40 #include "gnunet_applications.h"
41 #include "gnunet_mesh_service.h"
42 #include "gnunet_statistics_service.h"
43 #include "gnunet_constants.h"
44 #include "gnunet_tun_lib.h"
48 * Information about an address.
53 * AF_INET or AF_INET6.
58 * Remote address information.
63 * Address, if af is AF_INET.
68 * Address, if af is AF_INET6.
74 * IPPROTO_TCP or IPPROTO_UDP;
79 * Remote port, in host byte order!
86 * This struct is saved into the services-hashmap to represent
87 * a service this peer is specifically offering an exit for
88 * (for a specific domain name).
94 * Remote address to use for the service.
96 struct SocketAddress address;
99 * DNS name of the service.
104 * Port I am listening on within GNUnet for this service, in host
105 * byte order. (as we may redirect ports).
112 * Information we use to track a connection (the classical 6-tuple of
113 * IP-version, protocol, source-IP, destination-IP, source-port and
116 struct RedirectInformation
120 * Address information for the other party (equivalent of the
121 * arguments one would give to "connect").
123 struct SocketAddress remote_address;
126 * Address information we used locally (AF and proto must match
127 * "remote_address"). Equivalent of the arguments one would give to
130 struct SocketAddress local_address;
133 Note 1: additional information might be added here in the
134 future to support protocols that require special handling,
137 Note 2: we might also sometimes not match on all components
138 of the tuple, to support protocols where things do not always
145 * Queue of messages to a tunnel.
147 struct TunnelMessageQueue
150 * This is a doubly-linked list.
152 struct TunnelMessageQueue *next;
155 * This is a doubly-linked list.
157 struct TunnelMessageQueue *prev;
160 * Payload to send via the tunnel.
165 * Number of bytes in 'payload'.
172 * This struct is saved into connections_map to allow finding the
173 * right tunnel given an IP packet from TUN. It is also associated
174 * with the tunnel's closure so we can find it again for the next
175 * message from the tunnel.
180 * Mesh tunnel that is used for this connection.
182 struct GNUNET_MESH_Tunnel *tunnel;
185 * Heap node for this state in the connections_heap.
187 struct GNUNET_CONTAINER_HeapNode *heap_node;
190 * Key this state has in the connections_map.
192 GNUNET_HashCode state_key;
195 * Associated service record, or NULL for no service.
197 struct LocalService *serv;
200 * Head of DLL of messages for this tunnel.
202 struct TunnelMessageQueue *head;
205 * Tail of DLL of messages for this tunnel.
207 struct TunnelMessageQueue *tail;
210 * Active tunnel transmission request (or NULL).
212 struct GNUNET_MESH_TransmitHandle *th;
215 * Primary redirection information for this connection.
217 struct RedirectInformation ri;
223 * The handle to the configuration used throughout the process
225 static const struct GNUNET_CONFIGURATION_Handle *cfg;
228 * The handle to the helper
230 static struct GNUNET_HELPER_Handle *helper_handle;
233 * Arguments to the exit helper.
235 static char *exit_argv[7];
238 * IPv6 address of our TUN interface.
240 static struct in6_addr exit_ipv6addr;
243 * IPv6 prefix (0..127) from configuration file.
245 static unsigned long long ipv6prefix;
248 * IPv4 address of our TUN interface.
250 static struct in_addr exit_ipv4addr;
253 * IPv4 netmask of our TUN interface.
255 static struct in_addr exit_ipv4mask;
261 static struct GNUNET_STATISTICS_Handle *stats;
266 static struct GNUNET_MESH_Handle *mesh_handle;
269 * This hashmaps contains the mapping from peer, service-descriptor,
270 * source-port and destination-port to a struct TunnelState
272 static struct GNUNET_CONTAINER_MultiHashMap *connections_map;
275 * Heap so we can quickly find "old" connections.
277 static struct GNUNET_CONTAINER_Heap *connections_heap;
280 * If there are at least this many connections, old ones will be removed
282 static long long unsigned int max_connections;
285 * This hashmaps saves interesting things about the configured UDP services
287 static struct GNUNET_CONTAINER_MultiHashMap *udp_services;
290 * This hashmaps saves interesting things about the configured TCP services
292 static struct GNUNET_CONTAINER_MultiHashMap *tcp_services;
295 * Are we an IPv4-exit?
297 static int ipv4_exit;
300 * Are we an IPv6-exit?
302 static int ipv6_exit;
305 * Do we support IPv4 at all on the TUN interface?
307 static int ipv4_enabled;
310 * Do we support IPv6 at all on the TUN interface?
312 static int ipv6_enabled;
316 * Given IP information about a connection, calculate the respective
317 * hash we would use for the 'connections_map'.
319 * @param hash resulting hash
320 * @param ri information about the connection
323 hash_redirect_info (GNUNET_HashCode *hash,
324 const struct RedirectInformation *ri)
328 memset (hash, 0, sizeof (GNUNET_HashCode));
329 /* the GNUnet hashmap only uses the first sizeof(unsigned int) of the hash,
330 so we put the IP address in there (and hope for few collisions) */
332 switch (ri->remote_address.af)
335 memcpy (off, &ri->remote_address.address.ipv4, sizeof (struct in_addr));
336 off += sizeof (struct in_addr);
339 memcpy (off, &ri->remote_address.address.ipv6, sizeof (struct in6_addr));
340 off += sizeof (struct in_addr);
345 memcpy (off, &ri->remote_address.port, sizeof (uint16_t));
346 off += sizeof (uint16_t);
347 switch (ri->local_address.af)
350 memcpy (off, &ri->local_address.address.ipv4, sizeof (struct in_addr));
351 off += sizeof (struct in_addr);
354 memcpy (off, &ri->local_address.address.ipv6, sizeof (struct in6_addr));
355 off += sizeof (struct in_addr);
360 memcpy (off, &ri->local_address.port, sizeof (uint16_t));
361 off += sizeof (uint16_t);
362 memcpy (off, &ri->remote_address.proto, sizeof (uint8_t));
363 off += sizeof (uint8_t);
368 * Get our connection tracking state. Warns if it does not exists,
369 * refreshes the timestamp if it does exist.
371 * @param af address family
372 * @param protocol IPPROTO_UDP or IPPROTO_TCP
373 * @param destination_ip target IP
374 * @param destination_port target port
375 * @param local_ip local IP
376 * @param local_port local port
377 * @param state_key set to hash's state if non-NULL
378 * @return NULL if we have no tracking information for this tuple
380 static struct TunnelState *
381 get_redirect_state (int af,
383 const void *destination_ip,
384 uint16_t destination_port,
385 const void *local_ip,
387 GNUNET_HashCode *state_key)
389 struct RedirectInformation ri;
391 struct TunnelState *state;
393 ri.remote_address.af = af;
395 ri.remote_address.address.ipv4 = *((struct in_addr*) destination_ip);
397 ri.remote_address.address.ipv6 = * ((struct in6_addr*) destination_ip);
398 ri.remote_address.port = destination_port;
399 ri.remote_address.proto = protocol;
400 ri.local_address.af = af;
402 ri.local_address.address.ipv4 = *((struct in_addr*) local_ip);
404 ri.local_address.address.ipv6 = * ((struct in6_addr*) local_ip);
405 ri.local_address.port = local_port;
406 ri.local_address.proto = protocol;
407 hash_redirect_info (&key, &ri);
408 if (NULL != state_key)
410 state = GNUNET_CONTAINER_multihashmap_get (connections_map, &key);
413 /* Mark this connection as freshly used */
414 if (NULL == state_key)
415 GNUNET_CONTAINER_heap_update_cost (connections_heap,
417 GNUNET_TIME_absolute_get ().abs_value);
423 * Given a service descriptor and a destination port, find the
424 * respective service entry.
426 * @param service_map map of services (TCP or UDP)
427 * @param desc service descriptor
428 * @param dpt destination port
429 * @return NULL if we are not aware of such a service
431 static struct LocalService *
432 find_service (struct GNUNET_CONTAINER_MultiHashMap *service_map,
433 const GNUNET_HashCode *desc,
436 char key[sizeof (GNUNET_HashCode) + sizeof (uint16_t)];
438 memcpy (&key[0], &dpt, sizeof (uint16_t));
439 memcpy (&key[sizeof(uint16_t)], desc, sizeof (GNUNET_HashCode));
440 return GNUNET_CONTAINER_multihashmap_get (service_map,
441 (GNUNET_HashCode *) key);
446 * Free memory associated with a service record.
449 * @param key service descriptor
450 * @param value service record to free
454 free_service_record (void *cls,
455 const GNUNET_HashCode *key,
458 struct LocalService *service = value;
460 GNUNET_free_non_null (service->name);
461 GNUNET_free (service);
467 * Given a service descriptor and a destination port, find the
468 * respective service entry.
470 * @param service_map map of services (TCP or UDP)
471 * @param name name of the service
472 * @param dpt destination port
473 * @param service service information record to store (service->name will be set).
476 store_service (struct GNUNET_CONTAINER_MultiHashMap *service_map,
479 struct LocalService *service)
481 char key[sizeof (GNUNET_HashCode) + sizeof (uint16_t)];
482 GNUNET_HashCode desc;
484 GNUNET_CRYPTO_hash (name, strlen (name) + 1, &desc);
485 service->name = GNUNET_strdup (name);
486 memcpy (&key[0], &dpt, sizeof (uint16_t));
487 memcpy (&key[sizeof(uint16_t)], &desc, sizeof (GNUNET_HashCode));
489 GNUNET_CONTAINER_multihashmap_put (service_map,
490 (GNUNET_HashCode *) key,
492 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
494 free_service_record (NULL, (GNUNET_HashCode *) key, service);
495 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
496 _("Got duplicate service records for `%s:%u'\n"),
504 * MESH is ready to receive a message for the tunnel. Transmit it.
506 * @param cls the 'struct TunnelState'.
507 * @param size number of bytes available in buf
508 * @param buf where to copy the message
509 * @return number of bytes copied to buf
512 send_to_peer_notify_callback (void *cls, size_t size, void *buf)
514 struct TunnelState *s = cls;
515 struct GNUNET_MESH_Tunnel *tunnel = s->tunnel;
516 struct TunnelMessageQueue *tnq;
520 GNUNET_assert (size >= tnq->len);
521 memcpy (buf, tnq->payload, tnq->len);
523 GNUNET_CONTAINER_DLL_remove (s->head,
527 if (NULL != (tnq = s->head))
528 s->th = GNUNET_MESH_notify_transmit_ready (tunnel,
529 GNUNET_NO /* corking */,
531 GNUNET_TIME_UNIT_FOREVER_REL,
534 &send_to_peer_notify_callback,
536 GNUNET_STATISTICS_update (stats,
537 gettext_noop ("# Bytes transmitted via mesh tunnels"),
544 * Send the given packet via the mesh tunnel.
546 * @param mesh_tunnel destination
547 * @param tnq message to queue
550 send_packet_to_mesh_tunnel (struct GNUNET_MESH_Tunnel *mesh_tunnel,
551 struct TunnelMessageQueue *tnq)
553 struct TunnelState *s;
555 s = GNUNET_MESH_tunnel_get_data (mesh_tunnel);
556 GNUNET_assert (NULL != s);
557 GNUNET_CONTAINER_DLL_insert_tail (s->head, s->tail, tnq);
559 s->th = GNUNET_MESH_notify_transmit_ready (mesh_tunnel, GNUNET_NO /* cork */, 0 /* priority */,
560 GNUNET_TIME_UNIT_FOREVER_REL,
562 &send_to_peer_notify_callback,
568 * @brief Handles an UDP packet received from the helper.
570 * @param udp A pointer to the Packet
571 * @param pktlen number of bytes in 'udp'
572 * @param af address family (AFINET or AF_INET6)
573 * @param destination_ip destination IP-address of the IP packet (should
574 * be our local address)
575 * @param source_ip original source IP-address of the IP packet (should
576 * be the original destination address)
579 udp_from_helper (const struct GNUNET_TUN_UdpHeader *udp,
582 const void *destination_ip,
583 const void *source_ip)
585 struct TunnelState *state;
586 struct TunnelMessageQueue *tnq;
587 struct GNUNET_EXIT_UdpReplyMessage *urm;
591 char sbuf[INET6_ADDRSTRLEN];
592 char dbuf[INET6_ADDRSTRLEN];
593 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
594 "Received UDP packet going from %s:%u to %s:%u\n",
597 sbuf, sizeof (sbuf)),
598 (unsigned int) ntohs (udp->spt),
601 dbuf, sizeof (dbuf)),
602 (unsigned int) ntohs (udp->dpt));
604 if (pktlen < sizeof (struct GNUNET_TUN_UdpHeader))
610 if (pktlen != ntohs (udp->len))
616 state = get_redirect_state (af, IPPROTO_UDP,
624 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
625 _("Packet dropped, have no matching connection information\n"));
628 mlen = sizeof (struct GNUNET_EXIT_UdpReplyMessage) + pktlen - sizeof (struct GNUNET_TUN_UdpHeader);
629 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueue) + mlen);
630 tnq->payload = &tnq[1];
632 urm = (struct GNUNET_EXIT_UdpReplyMessage *) &tnq[1];
633 urm->header.size = htons ((uint16_t) mlen);
634 urm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_UDP_REPLY);
635 urm->source_port = htons (0);
636 urm->destination_port = htons (0);
639 pktlen - sizeof (struct GNUNET_TUN_UdpHeader));
640 send_packet_to_mesh_tunnel (state->tunnel,
646 * @brief Handles a TCP packet received from the helper.
648 * @param tcp A pointer to the Packet
649 * @param pktlen the length of the packet, including its TCP header
650 * @param af address family (AFINET or AF_INET6)
651 * @param destination_ip destination IP-address of the IP packet (should
652 * be our local address)
653 * @param source_ip original source IP-address of the IP packet (should
654 * be the original destination address)
657 tcp_from_helper (const struct GNUNET_TUN_TcpHeader *tcp,
660 const void *destination_ip,
661 const void *source_ip)
663 struct TunnelState *state;
665 struct GNUNET_TUN_TcpHeader *mtcp;
666 struct GNUNET_EXIT_TcpDataMessage *tdm;
667 struct TunnelMessageQueue *tnq;
671 char sbuf[INET6_ADDRSTRLEN];
672 char dbuf[INET6_ADDRSTRLEN];
673 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
674 "Received TCP packet with %u bytes going from %s:%u to %s:%u\n",
675 pktlen - sizeof (struct GNUNET_TUN_TcpHeader),
678 sbuf, sizeof (sbuf)),
679 (unsigned int) ntohs (tcp->spt),
682 dbuf, sizeof (dbuf)),
683 (unsigned int) ntohs (tcp->dpt));
685 if (pktlen < sizeof (struct GNUNET_TUN_TcpHeader))
691 state = get_redirect_state (af, IPPROTO_TCP,
699 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
700 _("Packet dropped, have no matching connection information\n"));
704 /* mug port numbers and crc to avoid information leakage;
705 sender will need to lookup the correct values anyway */
706 memcpy (buf, tcp, pktlen);
707 mtcp = (struct GNUNET_TUN_TcpHeader *) buf;
712 mlen = sizeof (struct GNUNET_EXIT_TcpDataMessage) + (pktlen - sizeof (struct GNUNET_TUN_TcpHeader));
713 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
719 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueue) + mlen);
720 tnq->payload = &tnq[1];
722 tdm = (struct GNUNET_EXIT_TcpDataMessage *) &tnq[1];
723 tdm->header.size = htons ((uint16_t) mlen);
724 tdm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_DATA);
725 tdm->reserved = htonl (0);
726 memcpy (&tdm->tcp_header,
729 send_packet_to_mesh_tunnel (state->tunnel,
735 * Receive packets from the helper-process
738 * @param client unsued
739 * @param message message received from helper
742 message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED,
743 const struct GNUNET_MessageHeader *message)
745 const struct GNUNET_TUN_Layer2PacketHeader *pkt_tun;
748 GNUNET_STATISTICS_update (stats,
749 gettext_noop ("# Packets received from TUN"),
751 if (ntohs (message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER)
756 size = ntohs (message->size);
757 if (size < sizeof (struct GNUNET_TUN_Layer2PacketHeader) + sizeof (struct GNUNET_MessageHeader))
762 GNUNET_STATISTICS_update (stats,
763 gettext_noop ("# Bytes received from TUN"),
765 pkt_tun = (const struct GNUNET_TUN_Layer2PacketHeader *) &message[1];
766 size -= sizeof (struct GNUNET_TUN_Layer2PacketHeader) + sizeof (struct GNUNET_MessageHeader);
767 switch (ntohs (pkt_tun->proto))
771 const struct GNUNET_TUN_IPv4Header *pkt4;
773 if (size < sizeof (struct GNUNET_TUN_IPv4Header))
775 /* Kernel to blame? */
779 pkt4 = (const struct GNUNET_TUN_IPv4Header *) &pkt_tun[1];
780 if (size != ntohs (pkt4->total_length))
782 /* Kernel to blame? */
786 if (pkt4->header_length * 4 != sizeof (struct GNUNET_TUN_IPv4Header))
788 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
789 _("IPv4 packet options received. Ignored.\n"));
792 size -= sizeof (struct GNUNET_TUN_IPv4Header);
793 switch (pkt4->protocol)
796 udp_from_helper ((const struct GNUNET_TUN_UdpHeader *) &pkt4[1], size,
798 &pkt4->destination_address,
799 &pkt4->source_address);
801 tcp_from_helper ((const struct GNUNET_TUN_TcpHeader *) &pkt4[1], size,
803 &pkt4->destination_address,
804 &pkt4->source_address);
807 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
808 _("IPv4 packet with unsupported next header received. Ignored.\n"));
815 const struct GNUNET_TUN_IPv6Header *pkt6;
817 if (size < sizeof (struct GNUNET_TUN_IPv6Header))
819 /* Kernel to blame? */
823 pkt6 = (struct GNUNET_TUN_IPv6Header *) &pkt_tun[1];
824 if (size != ntohs (pkt6->payload_length))
826 /* Kernel to blame? */
830 size -= sizeof (struct GNUNET_TUN_IPv6Header);
831 switch (pkt6->next_header)
834 udp_from_helper ((const struct GNUNET_TUN_UdpHeader *) &pkt6[1], size,
836 &pkt6->destination_address,
837 &pkt6->source_address);
840 tcp_from_helper ((const struct GNUNET_TUN_TcpHeader *) &pkt6[1], size,
842 &pkt6->destination_address,
843 &pkt6->source_address);
846 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
847 _("IPv6 packet with unsupported next header received. Ignored.\n"));
853 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
854 _("Packet from unknown protocol %u received. Ignored.\n"),
855 ntohs (pkt_tun->proto));
862 * We need to create a (unique) fresh local address (IP+port).
865 * @param af desired address family
866 * @param proto desired protocol (IPPROTO_UDP or IPPROTO_TCP)
867 * @param local_address address to initialize
870 setup_fresh_address (int af,
872 struct SocketAddress *local_address)
874 local_address->af = af;
875 local_address->proto = (uint8_t) proto;
876 /* default "local" port range is often 32768--61000,
877 so we pick a random value in that range */
879 = (uint16_t) 32768 + GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
889 addr = exit_ipv4addr;
890 mask = exit_ipv4mask;
891 if (0 == ~mask.s_addr)
893 /* only one valid IP anyway */
894 local_address->address.ipv4 = addr;
897 /* Given 192.168.0.1/255.255.0.0, we want a mask
898 of '192.168.255.255', thus: */
899 mask.s_addr = addr.s_addr | ~mask.s_addr;
900 /* Pick random IPv4 address within the subnet, except 'addr' or 'mask' itself */
903 rnd.s_addr = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
905 local_address->address.ipv4.s_addr = (addr.s_addr | rnd.s_addr) & mask.s_addr;
907 while ( (local_address->address.ipv4.s_addr == addr.s_addr) ||
908 (local_address->address.ipv4.s_addr == mask.s_addr) );
913 struct in6_addr addr;
914 struct in6_addr mask;
918 addr = exit_ipv6addr;
919 GNUNET_assert (ipv6prefix < 128);
920 if (ipv6prefix == 127)
922 /* only one valid IP anyway */
923 local_address->address.ipv6 = addr;
926 /* Given ABCD::/96, we want a mask of 'ABCD::FFFF:FFFF,
929 for (i=127;i>=128-ipv6prefix;i--)
930 mask.s6_addr[i / 8] |= (1 << (i % 8));
932 /* Pick random IPv6 address within the subnet, except 'addr' or 'mask' itself */
937 rnd.s6_addr[i] = (unsigned char) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
939 local_address->address.ipv6.s6_addr[i]
940 = (addr.s6_addr[i] | rnd.s6_addr[i]) & mask.s6_addr[i];
943 while ( (0 == memcmp (&local_address->address.ipv6,
945 sizeof (struct in6_addr))) ||
946 (0 == memcmp (&local_address->address.ipv6,
948 sizeof (struct in6_addr))) );
958 * We are starting a fresh connection (TCP or UDP) and need
959 * to pick a source port and IP address (within the correct
960 * range and address family) to associate replies with the
961 * connection / correct mesh tunnel. This function generates
962 * a "fresh" source IP and source port number for a connection
963 * After picking a good source address, this function sets up
964 * the state in the 'connections_map' and 'connections_heap'
965 * to allow finding the state when needed later. The function
966 * also makes sure that we remain within memory limits by
967 * cleaning up 'old' states.
969 * @param state skeleton state to setup a record for; should
970 * 'state->ri.remote_address' filled in so that
971 * this code can determine which AF/protocol is
972 * going to be used (the 'tunnel' should also
973 * already be set); after calling this function,
974 * heap_node and the local_address will be
975 * also initialized (heap_node != NULL can be
976 * used to test if a state has been fully setup).
979 setup_state_record (struct TunnelState *state)
982 struct TunnelState *s;
984 /* generate fresh, unique address */
987 if (NULL == state->serv)
988 setup_fresh_address (state->ri.remote_address.af,
989 state->ri.remote_address.proto,
990 &state->ri.local_address);
992 setup_fresh_address (state->serv->address.af,
993 state->serv->address.proto,
994 &state->ri.local_address);
995 } while (NULL != get_redirect_state (state->ri.remote_address.af,
996 state->ri.remote_address.proto,
997 &state->ri.remote_address.address,
998 state->ri.remote_address.port,
999 &state->ri.local_address.address,
1000 state->ri.local_address.port,
1003 char buf[INET6_ADDRSTRLEN];
1004 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1005 "Picked local address %s:%u for new connection\n",
1006 inet_ntop (state->ri.local_address.af,
1007 &state->ri.local_address.address,
1009 (unsigned int) state->ri.local_address.port);
1011 state->state_key = key;
1012 GNUNET_assert (GNUNET_OK ==
1013 GNUNET_CONTAINER_multihashmap_put (connections_map,
1015 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1016 state->heap_node = GNUNET_CONTAINER_heap_insert (connections_heap,
1018 GNUNET_TIME_absolute_get ().abs_value);
1019 while (GNUNET_CONTAINER_heap_get_size (connections_heap) > max_connections)
1021 s = GNUNET_CONTAINER_heap_remove_root (connections_heap);
1022 GNUNET_assert (state != s);
1023 s->heap_node = NULL;
1024 GNUNET_MESH_tunnel_destroy (s->tunnel);
1025 GNUNET_assert (GNUNET_OK ==
1026 GNUNET_CONTAINER_multihashmap_remove (connections_map,
1035 * Prepare an IPv4 packet for transmission via the TUN interface.
1036 * Initializes the IP header and calculates checksums (IP+UDP/TCP).
1037 * For UDP, the UDP header will be fully created, whereas for TCP
1038 * only the ports and checksum will be filled in. So for TCP,
1039 * a skeleton TCP header must be part of the provided payload.
1041 * @param payload payload of the packet (starting with UDP payload or
1042 * TCP header, depending on protocol)
1043 * @param payload_length number of bytes in 'payload'
1044 * @param protocol IPPROTO_UDP or IPPROTO_TCP
1045 * @param src_address source address to use (IP and port)
1046 * @param dst_address destination address to use (IP and port)
1047 * @param pkt6 where to write the assembled packet; must
1048 * contain enough space for the IP header, UDP/TCP header
1052 prepare_ipv4_packet (const void *payload, size_t payload_length,
1054 const struct GNUNET_TUN_TcpHeader *tcp_header,
1055 const struct SocketAddress *src_address,
1056 const struct SocketAddress *dst_address,
1057 struct GNUNET_TUN_IPv4Header *pkt4)
1061 len = payload_length;
1065 len += sizeof (struct GNUNET_TUN_UdpHeader);
1068 len += sizeof (struct GNUNET_TUN_TcpHeader);
1069 GNUNET_assert (NULL != tcp_header);
1075 if (len + sizeof (struct GNUNET_TUN_IPv4Header) > UINT16_MAX)
1081 GNUNET_TUN_initialize_ipv4_header (pkt4,
1084 &src_address->address.ipv4,
1085 &dst_address->address.ipv4);
1090 struct GNUNET_TUN_UdpHeader *pkt4_udp = (struct GNUNET_TUN_UdpHeader *) &pkt4[1];
1092 pkt4_udp->spt = htons (src_address->port);
1093 pkt4_udp->dpt = htons (dst_address->port);
1094 pkt4_udp->len = htons ((uint16_t) payload_length);
1095 GNUNET_TUN_calculate_udp4_checksum (pkt4,
1097 payload, payload_length);
1098 memcpy (&pkt4_udp[1], payload, payload_length);
1103 struct GNUNET_TUN_TcpHeader *pkt4_tcp = (struct GNUNET_TUN_TcpHeader *) &pkt4[1];
1105 memcpy (pkt4_tcp, tcp_header, sizeof (struct GNUNET_TUN_TcpHeader));
1106 pkt4_tcp->spt = htons (src_address->port);
1107 pkt4_tcp->dpt = htons (dst_address->port);
1108 GNUNET_TUN_calculate_tcp4_checksum (pkt4,
1112 memcpy (&pkt4_tcp[1], payload, payload_length);
1122 * Prepare an IPv6 packet for transmission via the TUN interface.
1123 * Initializes the IP header and calculates checksums (IP+UDP/TCP).
1124 * For UDP, the UDP header will be fully created, whereas for TCP
1125 * only the ports and checksum will be filled in. So for TCP,
1126 * a skeleton TCP header must be part of the provided payload.
1128 * @param payload payload of the packet (starting with UDP payload or
1129 * TCP header, depending on protocol)
1130 * @param payload_length number of bytes in 'payload'
1131 * @param protocol IPPROTO_UDP or IPPROTO_TCP
1132 * @param src_address source address to use (IP and port)
1133 * @param dst_address destination address to use (IP and port)
1134 * @param pkt6 where to write the assembled packet; must
1135 * contain enough space for the IP header, UDP/TCP header
1139 prepare_ipv6_packet (const void *payload, size_t payload_length,
1141 const struct GNUNET_TUN_TcpHeader *tcp_header,
1142 const struct SocketAddress *src_address,
1143 const struct SocketAddress *dst_address,
1144 struct GNUNET_TUN_IPv6Header *pkt6)
1148 len = payload_length;
1152 len += sizeof (struct GNUNET_TUN_UdpHeader);
1155 /* tcp_header (with port/crc not set) must be part of payload! */
1156 if (len < sizeof (struct GNUNET_TUN_TcpHeader))
1166 if (len > UINT16_MAX)
1172 GNUNET_TUN_initialize_ipv6_header (pkt6,
1175 &dst_address->address.ipv6,
1176 &src_address->address.ipv6);
1182 struct GNUNET_TUN_UdpHeader *pkt6_udp = (struct GNUNET_TUN_UdpHeader *) &pkt6[1];
1184 pkt6_udp->spt = htons (src_address->port);
1185 pkt6_udp->dpt = htons (dst_address->port);
1186 pkt6_udp->len = htons ((uint16_t) payload_length);
1188 GNUNET_TUN_calculate_udp6_checksum (pkt6,
1192 memcpy (&pkt6[1], payload, payload_length);
1197 struct GNUNET_TUN_TcpHeader *pkt6_tcp = (struct GNUNET_TUN_TcpHeader *) pkt6;
1199 /* memcpy first here as some TCP header fields are initialized this way! */
1200 memcpy (pkt6_tcp, payload, payload_length);
1201 pkt6_tcp->spt = htons (src_address->port);
1202 pkt6_tcp->dpt = htons (dst_address->port);
1203 GNUNET_TUN_calculate_tcp6_checksum (pkt6,
1217 * Send a TCP packet via the TUN interface.
1219 * @param destination_address IP and port to use for the TCP packet's destination
1220 * @param source_address IP and port to use for the TCP packet's source
1221 * @param tcp header template to use
1222 * @param payload payload of the TCP packet
1223 * @param payload_length number of bytes in 'payload'
1226 send_tcp_packet_via_tun (const struct SocketAddress *destination_address,
1227 const struct SocketAddress *source_address,
1228 const struct GNUNET_TUN_TcpHeader *tcp_header,
1229 const void *payload, size_t payload_length)
1233 GNUNET_STATISTICS_update (stats,
1234 gettext_noop ("# TCP packets sent via TUN"),
1236 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1237 "Sending packet with %u bytes TCP payload via TUN\n",
1238 (unsigned int) payload_length);
1239 len = sizeof (struct GNUNET_MessageHeader) + sizeof (struct GNUNET_TUN_Layer2PacketHeader);
1240 switch (source_address->af)
1243 len += sizeof (struct GNUNET_TUN_IPv4Header);
1246 len += sizeof (struct GNUNET_TUN_IPv6Header);
1252 len += sizeof (struct GNUNT_TUN_TcpHeader);
1253 len += payload_length;
1254 if (len >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1261 struct GNUNET_MessageHeader *hdr;
1262 struct GNUNET_TUN_Layer2PacketHeader *tun;
1264 hdr = (struct GNUNET_MessageHeader *) buf;
1265 hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1266 hdr->size = htons (len);
1267 tun = (struct GNUNET_TUN_Layer2PacketHeader*) &hdr[1];
1268 tun->flags = htons (0);
1269 switch (source_address->af)
1273 struct GNUNET_TUN_IPv4Header * ipv4 = (struct GNUNET_TUN_IPv4Header*) &tun[1];
1275 tun->proto = htons (ETH_P_IPV4);
1276 prepare_ipv4_packet (payload, payload_length,
1280 destination_address,
1286 struct GNUNET_TUN_IPv6Header * ipv6 = (struct GNUNET_TUN_IPv6Header*) &tun[1];
1288 tun->proto = htons (ETH_P_IPV6);
1289 prepare_ipv6_packet (payload, payload_length,
1293 destination_address,
1301 (void) GNUNET_HELPER_send (helper_handle,
1302 (const struct GNUNET_MessageHeader*) buf,
1310 * Process a request via mesh to send a request to a TCP service
1311 * offered by this system.
1313 * @param cls closure, NULL
1314 * @param tunnel connection to the other end
1315 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1316 * @param sender who sent the message
1317 * @param message the actual message
1318 * @param atsi performance data for the connection
1319 * @return GNUNET_OK to keep the connection open,
1320 * GNUNET_SYSERR to close it (signal serious error)
1323 receive_tcp_service (void *unused GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1324 void **tunnel_ctx GNUNET_UNUSED,
1325 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1326 const struct GNUNET_MessageHeader *message,
1327 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1329 struct TunnelState *state = *tunnel_ctx;
1330 const struct GNUNET_EXIT_TcpServiceStartMessage *start;
1331 uint16_t pkt_len = ntohs (message->size);
1333 GNUNET_STATISTICS_update (stats,
1334 gettext_noop ("# TCP service creation requests received via mesh"),
1336 GNUNET_STATISTICS_update (stats,
1337 gettext_noop ("# Bytes received from MESH"),
1338 pkt_len, GNUNET_NO);
1339 /* check that we got at least a valid header */
1340 if (pkt_len < sizeof (struct GNUNET_EXIT_TcpServiceStartMessage))
1342 GNUNET_break_op (0);
1343 return GNUNET_SYSERR;
1345 start = (const struct GNUNET_EXIT_TcpServiceStartMessage*) message;
1346 pkt_len -= sizeof (struct GNUNET_EXIT_TcpServiceStartMessage);
1347 if ( (NULL == state) ||
1348 (NULL != state->serv) ||
1349 (NULL != state->heap_node) )
1351 GNUNET_break_op (0);
1352 return GNUNET_SYSERR;
1354 GNUNET_break_op (ntohl (start->reserved) == 0);
1355 /* setup fresh connection */
1356 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1357 "Received data from %s for forwarding to TCP service %s on port %u\n",
1358 GNUNET_i2s (sender),
1359 GNUNET_h2s (&start->service_descriptor),
1360 (unsigned int) ntohs (start->tcp_header.dpt));
1361 if (NULL == (state->serv = find_service (tcp_services, &start->service_descriptor,
1362 ntohs (start->tcp_header.dpt))))
1364 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1365 _("No service found for %s on port %d!\n"),
1367 ntohs (start->tcp_header.dpt));
1368 GNUNET_STATISTICS_update (stats,
1369 gettext_noop ("# TCP requests dropped (no such service)"),
1371 return GNUNET_SYSERR;
1373 state->ri.remote_address = state->serv->address;
1374 setup_state_record (state);
1375 send_tcp_packet_via_tun (&state->ri.remote_address,
1376 &state->ri.local_address,
1378 &start[1], pkt_len);
1384 * Process a request to forward TCP data to the Internet via this peer.
1386 * @param cls closure, NULL
1387 * @param tunnel connection to the other end
1388 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1389 * @param sender who sent the message
1390 * @param message the actual message
1391 * @param atsi performance data for the connection
1392 * @return GNUNET_OK to keep the connection open,
1393 * GNUNET_SYSERR to close it (signal serious error)
1396 receive_tcp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1397 void **tunnel_ctx GNUNET_UNUSED,
1398 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1399 const struct GNUNET_MessageHeader *message,
1400 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1402 struct TunnelState *state = *tunnel_ctx;
1403 const struct GNUNET_EXIT_TcpInternetStartMessage *start;
1404 uint16_t pkt_len = ntohs (message->size);
1405 const struct in_addr *v4;
1406 const struct in6_addr *v6;
1407 const void *payload;
1410 GNUNET_STATISTICS_update (stats,
1411 gettext_noop ("# Bytes received from MESH"),
1412 pkt_len, GNUNET_NO);
1413 GNUNET_STATISTICS_update (stats,
1414 gettext_noop ("# TCP IP-exit creation requests received via mesh"),
1416 if (pkt_len < sizeof (struct GNUNET_EXIT_TcpInternetStartMessage))
1418 GNUNET_break_op (0);
1419 return GNUNET_SYSERR;
1421 start = (const struct GNUNET_EXIT_TcpInternetStartMessage*) message;
1422 pkt_len -= sizeof (struct GNUNET_EXIT_TcpInternetStartMessage);
1423 if ( (NULL == state) ||
1424 (NULL != state->serv) ||
1425 (NULL != state->heap_node) )
1427 GNUNET_break_op (0);
1428 return GNUNET_SYSERR;
1430 af = (int) ntohl (start->af);
1431 state->ri.remote_address.af = af;
1435 if (pkt_len < sizeof (struct in_addr))
1437 GNUNET_break_op (0);
1438 return GNUNET_SYSERR;
1442 GNUNET_break_op (0);
1443 return GNUNET_SYSERR;
1445 v4 = (const struct in_addr*) &start[1];
1447 pkt_len -= sizeof (struct in_addr);
1448 state->ri.remote_address.address.ipv4 = *v4;
1451 if (pkt_len < sizeof (struct in6_addr))
1453 GNUNET_break_op (0);
1454 return GNUNET_SYSERR;
1458 GNUNET_break_op (0);
1459 return GNUNET_SYSERR;
1461 v6 = (const struct in6_addr*) &start[1];
1463 pkt_len -= sizeof (struct in_addr);
1464 state->ri.remote_address.address.ipv6 = *v6;
1467 GNUNET_break_op (0);
1468 return GNUNET_SYSERR;
1471 char buf[INET6_ADDRSTRLEN];
1472 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1473 "Received data from %s for starting TCP stream to %s:%u\n",
1474 GNUNET_i2s (sender),
1476 &state->ri.remote_address.address,
1478 (unsigned int) ntohs (start->tcp_header.dpt));
1481 state->ri.remote_address.proto = IPPROTO_TCP;
1482 state->ri.remote_address.port = ntohs (start->tcp_header.dpt);
1483 setup_state_record (state);
1484 send_tcp_packet_via_tun (&state->ri.remote_address,
1485 &state->ri.local_address,
1493 * Process a request to forward TCP data on an established
1494 * connection via this peer.
1496 * @param cls closure, NULL
1497 * @param tunnel connection to the other end
1498 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1499 * @param sender who sent the message
1500 * @param message the actual message
1501 * @param atsi performance data for the connection
1502 * @return GNUNET_OK to keep the connection open,
1503 * GNUNET_SYSERR to close it (signal serious error)
1506 receive_tcp_data (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1507 void **tunnel_ctx GNUNET_UNUSED,
1508 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1509 const struct GNUNET_MessageHeader *message,
1510 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1512 struct TunnelState *state = *tunnel_ctx;
1513 const struct GNUNET_EXIT_TcpDataMessage *data;
1514 uint16_t pkt_len = ntohs (message->size);
1516 GNUNET_STATISTICS_update (stats,
1517 gettext_noop ("# Bytes received from MESH"),
1518 pkt_len, GNUNET_NO);
1519 GNUNET_STATISTICS_update (stats,
1520 gettext_noop ("# TCP data requests received via mesh"),
1522 if (pkt_len < sizeof (struct GNUNET_EXIT_TcpDataMessage))
1524 GNUNET_break_op (0);
1525 return GNUNET_SYSERR;
1527 data = (const struct GNUNET_EXIT_TcpDataMessage*) message;
1528 pkt_len -= sizeof (struct GNUNET_EXIT_TcpDataMessage);
1529 if ( (NULL == state) ||
1530 (NULL == state->heap_node) )
1532 /* connection should have been up! */
1533 GNUNET_STATISTICS_update (stats,
1534 gettext_noop ("# TCP DATA requests dropped (no session)"),
1536 return GNUNET_SYSERR;
1538 GNUNET_break_op (ntohl (data->reserved) == 0);
1540 char buf[INET6_ADDRSTRLEN];
1541 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1542 "Received additional %u bytes of data from %s for TCP stream to %s:%u\n",
1544 GNUNET_i2s (sender),
1545 inet_ntop (state->ri.remote_address.af,
1546 &state->ri.remote_address.address,
1548 (unsigned int) state->ri.remote_address.port);
1551 send_tcp_packet_via_tun (&state->ri.remote_address,
1552 &state->ri.local_address,
1560 * Send a UDP packet via the TUN interface.
1562 * @param destination_address IP and port to use for the UDP packet's destination
1563 * @param source_address IP and port to use for the UDP packet's source
1564 * @param payload payload of the UDP packet (does NOT include UDP header)
1565 * @param payload_length number of bytes of data in payload
1568 send_udp_packet_via_tun (const struct SocketAddress *destination_address,
1569 const struct SocketAddress *source_address,
1570 const void *payload, size_t payload_length)
1574 GNUNET_STATISTICS_update (stats,
1575 gettext_noop ("# UDP packets sent via TUN"),
1577 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1578 "Sending packet with %u bytes UDP payload via TUN\n",
1579 (unsigned int) payload_length);
1580 len = sizeof (struct GNUNET_MessageHeader) + sizeof (struct GNUNET_TUN_Layer2PacketHeader);
1581 switch (source_address->af)
1584 len += sizeof (struct GNUNET_TUN_IPv4Header);
1587 len += sizeof (struct GNUNET_TUN_IPv6Header);
1593 len += sizeof (struct GNUNET_TUN_UdpHeader);
1594 len += payload_length;
1595 if (len >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1602 struct GNUNET_MessageHeader *hdr;
1603 struct GNUNET_TUN_Layer2PacketHeader *tun;
1605 hdr= (struct GNUNET_MessageHeader *) buf;
1606 hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1607 hdr->size = htons (len);
1608 tun = (struct GNUNET_TUN_Layer2PacketHeader*) &hdr[1];
1609 tun->flags = htons (0);
1610 switch (source_address->af)
1614 struct GNUNET_TUN_IPv4Header * ipv4 = (struct GNUNET_TUN_IPv4Header*) &tun[1];
1616 tun->proto = htons (ETH_P_IPV4);
1617 prepare_ipv4_packet (payload, payload_length,
1621 destination_address,
1627 struct GNUNET_TUN_IPv6Header * ipv6 = (struct GNUNET_TUN_IPv6Header*) &tun[1];
1629 tun->proto = htons (ETH_P_IPV6);
1630 prepare_ipv6_packet (payload, payload_length,
1634 destination_address,
1642 (void) GNUNET_HELPER_send (helper_handle,
1643 (const struct GNUNET_MessageHeader*) buf,
1651 * Process a request to forward UDP data to the Internet via this peer.
1653 * @param cls closure, NULL
1654 * @param tunnel connection to the other end
1655 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1656 * @param sender who sent the message
1657 * @param message the actual message
1658 * @param atsi performance data for the connection
1659 * @return GNUNET_OK to keep the connection open,
1660 * GNUNET_SYSERR to close it (signal serious error)
1663 receive_udp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1664 void **tunnel_ctx GNUNET_UNUSED,
1665 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1666 const struct GNUNET_MessageHeader *message,
1667 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1669 struct TunnelState *state = *tunnel_ctx;
1670 const struct GNUNET_EXIT_UdpInternetMessage *msg;
1671 uint16_t pkt_len = ntohs (message->size);
1672 const struct in_addr *v4;
1673 const struct in6_addr *v6;
1674 const void *payload;
1677 GNUNET_STATISTICS_update (stats,
1678 gettext_noop ("# Bytes received from MESH"),
1679 pkt_len, GNUNET_NO);
1680 GNUNET_STATISTICS_update (stats,
1681 gettext_noop ("# UDP IP-exit requests received via mesh"),
1683 if (pkt_len < sizeof (struct GNUNET_EXIT_UdpInternetMessage))
1685 GNUNET_break_op (0);
1686 return GNUNET_SYSERR;
1688 msg = (const struct GNUNET_EXIT_UdpInternetMessage*) message;
1689 pkt_len -= sizeof (struct GNUNET_EXIT_UdpInternetMessage);
1690 af = (int) ntohl (msg->af);
1691 state->ri.remote_address.af = af;
1695 if (pkt_len < sizeof (struct in_addr))
1697 GNUNET_break_op (0);
1698 return GNUNET_SYSERR;
1702 GNUNET_break_op (0);
1703 return GNUNET_SYSERR;
1705 v4 = (const struct in_addr*) &msg[1];
1707 pkt_len -= sizeof (struct in_addr);
1708 state->ri.remote_address.address.ipv4 = *v4;
1711 if (pkt_len < sizeof (struct in6_addr))
1713 GNUNET_break_op (0);
1714 return GNUNET_SYSERR;
1718 GNUNET_break_op (0);
1719 return GNUNET_SYSERR;
1721 v6 = (const struct in6_addr*) &msg[1];
1723 pkt_len -= sizeof (struct in_addr);
1724 state->ri.remote_address.address.ipv6 = *v6;
1727 GNUNET_break_op (0);
1728 return GNUNET_SYSERR;
1731 char buf[INET6_ADDRSTRLEN];
1732 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1733 "Received data from %s for forwarding to UDP %s:%u\n",
1734 GNUNET_i2s (sender),
1736 &state->ri.remote_address.address,
1738 (unsigned int) ntohs (msg->destination_port));
1740 state->ri.remote_address.proto = IPPROTO_UDP;
1741 state->ri.remote_address.port = msg->destination_port;
1742 if (NULL == state->heap_node)
1743 setup_state_record (state);
1744 if (0 != ntohs (msg->source_port))
1745 state->ri.local_address.port = msg->source_port;
1746 send_udp_packet_via_tun (&state->ri.remote_address,
1747 &state->ri.local_address,
1754 * Process a request via mesh to send a request to a UDP service
1755 * offered by this system.
1757 * @param cls closure, NULL
1758 * @param tunnel connection to the other end
1759 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1760 * @param sender who sent the message
1761 * @param message the actual message
1762 * @param atsi performance data for the connection
1763 * @return GNUNET_OK to keep the connection open,
1764 * GNUNET_SYSERR to close it (signal serious error)
1767 receive_udp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1769 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1770 const struct GNUNET_MessageHeader *message,
1771 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1773 struct TunnelState *state = *tunnel_ctx;
1774 const struct GNUNET_EXIT_UdpServiceMessage *msg;
1775 uint16_t pkt_len = ntohs (message->size);
1777 GNUNET_STATISTICS_update (stats,
1778 gettext_noop ("# Bytes received from MESH"),
1779 pkt_len, GNUNET_NO);
1780 GNUNET_STATISTICS_update (stats,
1781 gettext_noop ("# UDP service requests received via mesh"),
1783 /* check that we got at least a valid header */
1784 if (pkt_len < sizeof (struct GNUNET_EXIT_UdpServiceMessage))
1786 GNUNET_break_op (0);
1787 return GNUNET_SYSERR;
1789 msg = (const struct GNUNET_EXIT_UdpServiceMessage*) message;
1790 pkt_len -= sizeof (struct GNUNET_EXIT_UdpServiceMessage);
1791 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1792 "Received data from %s for forwarding to UDP service %s on port %u\n",
1793 GNUNET_i2s (sender),
1794 GNUNET_h2s (&msg->service_descriptor),
1795 (unsigned int) ntohs (msg->destination_port));
1796 if (NULL == (state->serv = find_service (udp_services, &msg->service_descriptor,
1797 ntohs (msg->destination_port))))
1799 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1800 _("No service found for %s on port %d!\n"),
1802 ntohs (msg->destination_port));
1803 GNUNET_STATISTICS_update (stats,
1804 gettext_noop ("# UDP requests dropped (no such service)"),
1806 return GNUNET_SYSERR;
1808 state->ri.remote_address = state->serv->address;
1809 setup_state_record (state);
1810 if (0 != ntohs (msg->source_port))
1811 state->ri.local_address.port = msg->source_port;
1812 send_udp_packet_via_tun (&state->ri.remote_address,
1813 &state->ri.local_address,
1820 * Callback from GNUNET_MESH for new tunnels.
1822 * @param cls closure
1823 * @param tunnel new handle to the tunnel
1824 * @param initiator peer that started the tunnel
1825 * @param atsi performance information for the tunnel
1826 * @return initial tunnel context for the tunnel
1829 new_tunnel (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1830 const struct GNUNET_PeerIdentity *initiator GNUNET_UNUSED,
1831 const struct GNUNET_ATS_Information *ats GNUNET_UNUSED)
1833 struct TunnelState *s = GNUNET_malloc (sizeof (struct TunnelState));
1835 GNUNET_STATISTICS_update (stats,
1836 gettext_noop ("# Inbound MESH tunnels created"),
1838 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1839 "Received inbound tunnel from `%s'\n",
1840 GNUNET_i2s (initiator));
1847 * Function called by mesh whenever an inbound tunnel is destroyed.
1848 * Should clean up any associated state.
1850 * @param cls closure (set from GNUNET_MESH_connect)
1851 * @param tunnel connection to the other end (henceforth invalid)
1852 * @param tunnel_ctx place where local state associated
1853 * with the tunnel is stored
1856 clean_tunnel (void *cls GNUNET_UNUSED, const struct GNUNET_MESH_Tunnel *tunnel,
1859 struct TunnelState *s = tunnel_ctx;
1860 struct TunnelMessageQueue *tnq;
1862 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1863 "Tunnel destroyed\n");
1864 while (NULL != (tnq = s->head))
1866 GNUNET_CONTAINER_DLL_remove (s->head,
1871 if (s->heap_node != NULL)
1873 GNUNET_assert (GNUNET_YES ==
1874 GNUNET_CONTAINER_multihashmap_remove (connections_map,
1877 GNUNET_CONTAINER_heap_remove_node (s->heap_node);
1878 s->heap_node = NULL;
1882 GNUNET_MESH_notify_transmit_ready_cancel (s->th);
1890 * Function that frees everything from a hashmap
1894 * @param value value to free
1897 free_iterate (void *cls GNUNET_UNUSED,
1898 const GNUNET_HashCode * hash GNUNET_UNUSED, void *value)
1900 GNUNET_free (value);
1906 * Function scheduled as very last function, cleans up after us
1909 cleanup (void *cls GNUNET_UNUSED,
1910 const struct GNUNET_SCHEDULER_TaskContext *tskctx)
1914 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1915 "Exit service is shutting down now\n");
1916 if (helper_handle != NULL)
1918 GNUNET_HELPER_stop (helper_handle);
1919 helper_handle = NULL;
1921 if (mesh_handle != NULL)
1923 GNUNET_MESH_disconnect (mesh_handle);
1926 if (NULL != connections_map)
1928 GNUNET_CONTAINER_multihashmap_iterate (connections_map, &free_iterate, NULL);
1929 GNUNET_CONTAINER_multihashmap_destroy (connections_map);
1930 connections_map = NULL;
1932 if (NULL != connections_heap)
1934 GNUNET_CONTAINER_heap_destroy (connections_heap);
1935 connections_heap = NULL;
1937 if (NULL != tcp_services)
1939 GNUNET_CONTAINER_multihashmap_iterate (tcp_services, &free_service_record, NULL);
1940 GNUNET_CONTAINER_multihashmap_destroy (tcp_services);
1941 tcp_services = NULL;
1943 if (NULL != udp_services)
1945 GNUNET_CONTAINER_multihashmap_iterate (udp_services, &free_service_record, NULL);
1946 GNUNET_CONTAINER_multihashmap_destroy (udp_services);
1947 udp_services = NULL;
1951 GNUNET_STATISTICS_destroy (stats, GNUNET_YES);
1955 GNUNET_free_non_null (exit_argv[i]);
1960 * Add services to the service map.
1962 * @param proto IPPROTO_TCP or IPPROTO_UDP
1963 * @param cpy copy of the service descriptor (can be mutilated)
1964 * @param name DNS name of the service
1967 add_services (int proto,
1974 struct LocalService *serv;
1976 for (redirect = strtok (cpy, " "); redirect != NULL;
1977 redirect = strtok (NULL, " "))
1979 if (NULL == (hostname = strstr (redirect, ":")))
1981 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1982 "option `%s' for domain `%s' is not formatted correctly!\n",
1989 if (NULL == (hostport = strstr (hostname, ":")))
1991 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1992 "option `%s' for domain `%s' is not formatted correctly!\n",
2000 int local_port = atoi (redirect);
2001 int remote_port = atoi (hostport);
2003 if (!((local_port > 0) && (local_port < 65536)))
2005 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2006 "`%s' is not a valid port number (for domain `%s')!", redirect,
2010 if (!((remote_port > 0) && (remote_port < 65536)))
2012 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2013 "`%s' is not a valid port number (for domain `%s')!", hostport,
2018 serv = GNUNET_malloc (sizeof (struct LocalService));
2019 serv->my_port = (uint16_t) local_port;
2020 serv->address.port = remote_port;
2021 if (0 == strcmp ("localhost4", hostname))
2023 const char *ip4addr = exit_argv[4];
2025 serv->address.af = AF_INET;
2026 GNUNET_assert (1 != inet_pton (AF_INET, ip4addr, &serv->address.address.ipv4));
2028 else if (0 == strcmp ("localhost6", hostname))
2030 const char *ip6addr = exit_argv[2];
2032 serv->address.af = AF_INET6;
2033 GNUNET_assert (1 == inet_pton (AF_INET6, ip6addr, &serv->address.address.ipv6));
2037 struct addrinfo *res;
2040 ret = getaddrinfo (hostname, NULL, NULL, &res);
2041 if ( (ret != 0) || (res == NULL) )
2043 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2044 _("No addresses found for hostname `%s' of service `%s'!\n"),
2051 serv->address.af = res->ai_family;
2052 switch (res->ai_family)
2057 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2058 _("Service `%s' configured for IPv4, but IPv4 is disabled!\n"),
2064 serv->address.address.ipv4 = ((struct sockaddr_in *) res->ai_addr)->sin_addr;
2069 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2070 _("Service `%s' configured for IPv4, but IPv4 is disabled!\n"),
2076 serv->address.address.ipv6 = ((struct sockaddr_in6 *) res->ai_addr)->sin6_addr;
2080 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2081 _("No IP addresses found for hostname `%s' of service `%s'!\n"),
2089 store_service ((IPPROTO_UDP == proto) ? udp_services : tcp_services,
2098 * Reads the configuration servicecfg and populates udp_services
2101 * @param section name of section in config, equal to hostname
2104 read_service_conf (void *cls GNUNET_UNUSED, const char *section)
2108 if ((strlen (section) < 8) ||
2109 (0 != strcmp (".gnunet.", section + (strlen (section) - 8))))
2112 GNUNET_CONFIGURATION_get_value_string (cfg, section, "UDP_REDIRECTS",
2115 add_services (IPPROTO_UDP, cpy, section);
2119 GNUNET_CONFIGURATION_get_value_string (cfg, section, "TCP_REDIRECTS",
2122 add_services (IPPROTO_TCP, cpy, section);
2129 * @brief Main function that will be run by the scheduler.
2131 * @param cls closure
2132 * @param args remaining command-line arguments
2133 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
2134 * @param cfg_ configuration
2137 run (void *cls, char *const *args GNUNET_UNUSED,
2138 const char *cfgfile GNUNET_UNUSED,
2139 const struct GNUNET_CONFIGURATION_Handle *cfg_)
2141 static struct GNUNET_MESH_MessageHandler handlers[] = {
2142 {&receive_udp_service, GNUNET_MESSAGE_TYPE_VPN_UDP_TO_SERVICE, 0},
2143 {&receive_udp_remote, GNUNET_MESSAGE_TYPE_VPN_UDP_TO_INTERNET, 0},
2144 {&receive_tcp_service, GNUNET_MESSAGE_TYPE_VPN_TCP_TO_SERVICE_START, 0},
2145 {&receive_tcp_remote, GNUNET_MESSAGE_TYPE_VPN_TCP_TO_INTERNET_START, 0},
2146 {&receive_tcp_data, GNUNET_MESSAGE_TYPE_VPN_TCP_DATA, 0},
2150 static GNUNET_MESH_ApplicationType apptypes[] = {
2151 GNUNET_APPLICATION_TYPE_END,
2152 GNUNET_APPLICATION_TYPE_END,
2153 GNUNET_APPLICATION_TYPE_END
2155 unsigned int app_idx;
2164 stats = GNUNET_STATISTICS_create ("exit", cfg);
2165 ipv4_exit = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "EXIT_IPV4");
2166 ipv6_exit = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "EXIT_IPV6");
2167 ipv4_enabled = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "ENABLE_IPV4");
2168 ipv6_enabled = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "ENABLE_IPV6");
2169 if (ipv4_exit && (! ipv4_enabled))
2171 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2172 _("Cannot enable IPv4 exit but disable IPv4 on TUN interface, will use ENABLE_IPv4=YES\n"));
2173 ipv4_enabled = GNUNET_YES;
2175 if (ipv6_exit && (! ipv6_enabled))
2177 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2178 _("Cannot enable IPv6 exit but disable IPv6 on TUN interface, will use ENABLE_IPv6=YES\n"));
2179 ipv6_enabled = GNUNET_YES;
2181 if (! (ipv4_enabled || ipv6_enabled))
2183 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2184 _("No useful service enabled. Exiting.\n"));
2185 GNUNET_SCHEDULER_shutdown ();
2189 if (GNUNET_YES == ipv4_exit)
2191 apptypes[app_idx] = GNUNET_APPLICATION_TYPE_IPV4_GATEWAY;
2194 if (GNUNET_YES == ipv6_exit)
2196 apptypes[app_idx] = GNUNET_APPLICATION_TYPE_IPV6_GATEWAY;
2200 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
2203 GNUNET_CONFIGURATION_get_value_number (cfg, "exit", "MAX_CONNECTIONS",
2205 max_connections = 1024;
2206 exit_argv[0] = GNUNET_strdup ("exit-gnunet");
2207 if (GNUNET_SYSERR ==
2208 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "TUN_IFNAME", &tun_ifname))
2210 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2211 "No entry 'TUN_IFNAME' in configuration!\n");
2212 GNUNET_SCHEDULER_shutdown ();
2215 exit_argv[1] = tun_ifname;
2218 if (GNUNET_SYSERR ==
2219 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "EXIT_IFNAME", &exit_ifname))
2221 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2222 "No entry 'EXIT_IFNAME' in configuration!\n");
2223 GNUNET_SCHEDULER_shutdown ();
2226 exit_argv[2] = exit_ifname;
2230 exit_argv[2] = GNUNET_strdup ("%");
2232 if (GNUNET_YES == ipv6_enabled)
2234 if ( (GNUNET_SYSERR ==
2235 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV6ADDR",
2237 (1 != inet_pton (AF_INET6, ipv6addr, &exit_ipv6addr))) )
2239 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2240 "No valid entry 'IPV6ADDR' in configuration!\n");
2241 GNUNET_SCHEDULER_shutdown ();
2244 exit_argv[3] = ipv6addr;
2245 if (GNUNET_SYSERR ==
2246 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV6PREFIX",
2249 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2250 "No entry 'IPV6PREFIX' in configuration!\n");
2251 GNUNET_SCHEDULER_shutdown ();
2254 exit_argv[4] = ipv6prefix_s;
2256 GNUNET_CONFIGURATION_get_value_number (cfg, "exit",
2259 (ipv6prefix >= 127) )
2261 GNUNET_SCHEDULER_shutdown ();
2267 /* IPv6 explicitly disabled */
2268 exit_argv[3] = GNUNET_strdup ("-");
2269 exit_argv[4] = GNUNET_strdup ("-");
2271 if (GNUNET_YES == ipv4_enabled)
2273 if ( (GNUNET_SYSERR ==
2274 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV4ADDR",
2276 (1 != inet_pton (AF_INET, ipv4addr, &exit_ipv4addr))) )
2278 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2279 "No valid entry for 'IPV4ADDR' in configuration!\n");
2280 GNUNET_SCHEDULER_shutdown ();
2283 exit_argv[5] = ipv4addr;
2284 if ( (GNUNET_SYSERR ==
2285 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV4MASK",
2287 (1 != inet_pton (AF_INET, ipv4mask, &exit_ipv4mask))) )
2289 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2290 "No valid entry 'IPV4MASK' in configuration!\n");
2291 GNUNET_SCHEDULER_shutdown ();
2294 exit_argv[6] = ipv4mask;
2298 /* IPv4 explicitly disabled */
2299 exit_argv[5] = GNUNET_strdup ("-");
2300 exit_argv[6] = GNUNET_strdup ("-");
2302 exit_argv[7] = NULL;
2304 udp_services = GNUNET_CONTAINER_multihashmap_create (65536);
2305 tcp_services = GNUNET_CONTAINER_multihashmap_create (65536);
2306 GNUNET_CONFIGURATION_iterate_sections (cfg, &read_service_conf, NULL);
2308 connections_map = GNUNET_CONTAINER_multihashmap_create (65536);
2309 connections_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
2311 = GNUNET_MESH_connect (cfg, 42 /* queue size */, NULL,
2313 &clean_tunnel, handlers,
2315 if (NULL == mesh_handle)
2317 GNUNET_SCHEDULER_shutdown ();
2320 helper_handle = GNUNET_HELPER_start ("gnunet-helper-exit",
2322 &message_token, NULL);
2329 * @param argc number of arguments from the command line
2330 * @param argv command line arguments
2331 * @return 0 ok, 1 on error
2334 main (int argc, char *const *argv)
2336 static const struct GNUNET_GETOPT_CommandLineOption options[] = {
2337 GNUNET_GETOPT_OPTION_END
2340 return (GNUNET_OK ==
2341 GNUNET_PROGRAM_run (argc, argv, "gnunet-daemon-exit",
2343 ("Daemon to run to provide an IP exit node for the VPN"),
2344 options, &run, NULL)) ? 0 : 1;
2348 /* end of gnunet-daemon-exit.c */