2 This file is part of GNUnet.
3 (C) 2010-2013 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
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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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_dht_service.h"
42 #include "gnunet_mesh_service.h"
43 #include "gnunet_dnsparser_lib.h"
44 #include "gnunet_dnsstub_lib.h"
45 #include "gnunet_statistics_service.h"
46 #include "gnunet_constants.h"
47 #include "gnunet_signatures.h"
48 #include "gnunet_tun_lib.h"
49 #include "gnunet_regex_service.h"
51 #include "block_dns.h"
55 * Maximum path compression length for mesh regex announcing for IPv4 address
58 #define REGEX_MAX_PATH_LEN_IPV4 4
61 * Maximum path compression length for mesh regex announcing for IPv6 address
64 #define REGEX_MAX_PATH_LEN_IPV6 8
67 * How frequently do we re-announce the regex for the exit?
69 #define REGEX_REFRESH_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 30)
72 * How frequently do we re-announce the DNS exit in the DHT?
74 #define DHT_PUT_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
77 * How long do we typically sign the DNS exit advertisement for?
79 #define DNS_ADVERTISEMENT_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 3)
83 * Generic logging shorthand
85 #define LOG(kind, ...) \
86 GNUNET_log_from (kind, "exit", __VA_ARGS__);
90 * Information about an address.
95 * AF_INET or AF_INET6.
100 * Remote address information.
105 * Address, if af is AF_INET.
110 * Address, if af is AF_INET6.
112 struct in6_addr ipv6;
116 * IPPROTO_TCP or IPPROTO_UDP;
121 * Remote port, in host byte order!
128 * This struct is saved into the services-hashmap to represent
129 * a service this peer is specifically offering an exit for
130 * (for a specific domain name).
136 * Remote address to use for the service.
138 struct SocketAddress address;
141 * DNS name of the service.
146 * Port I am listening on within GNUnet for this service, in host
147 * byte order. (as we may redirect ports).
154 * Information we use to track a connection (the classical 6-tuple of
155 * IP-version, protocol, source-IP, destination-IP, source-port and
158 struct RedirectInformation
162 * Address information for the other party (equivalent of the
163 * arguments one would give to "connect").
165 struct SocketAddress remote_address;
168 * Address information we used locally (AF and proto must match
169 * "remote_address"). Equivalent of the arguments one would give to
172 struct SocketAddress local_address;
175 Note 1: additional information might be added here in the
176 future to support protocols that require special handling,
179 Note 2: we might also sometimes not match on all components
180 of the tuple, to support protocols where things do not always
187 * Queue of messages to a tunnel.
189 struct TunnelMessageQueue
192 * This is a doubly-linked list.
194 struct TunnelMessageQueue *next;
197 * This is a doubly-linked list.
199 struct TunnelMessageQueue *prev;
202 * Payload to send via the tunnel.
207 * Number of bytes in 'payload'.
214 * This struct is saved into connections_map to allow finding the
215 * right tunnel given an IP packet from TUN. It is also associated
216 * with the tunnel's closure so we can find it again for the next
217 * message from the tunnel.
222 * Mesh tunnel that is used for this connection.
224 struct GNUNET_MESH_Tunnel *tunnel;
227 * Who is the other end of this tunnel.
228 * FIXME is this needed? Only used for debugging messages
230 struct GNUNET_PeerIdentity peer;
233 * Active tunnel transmission request (or NULL).
235 struct GNUNET_MESH_TransmitHandle *th;
238 * #GNUNET_NO if this is a tunnel for TCP/UDP,
239 * #GNUNET_YES if this is a tunnel for DNS,
240 * #GNUNET_SYSERR if the tunnel is not yet initialized.
250 * Heap node for this state in the connections_heap.
252 struct GNUNET_CONTAINER_HeapNode *heap_node;
255 * Key this state has in the connections_map.
257 struct GNUNET_HashCode state_key;
260 * Associated service record, or NULL for no service.
262 struct LocalService *serv;
265 * Head of DLL of messages for this tunnel.
267 struct TunnelMessageQueue *head;
270 * Tail of DLL of messages for this tunnel.
272 struct TunnelMessageQueue *tail;
275 * Primary redirection information for this connection.
277 struct RedirectInformation ri;
284 * DNS reply ready for transmission.
289 * Socket we are using to transmit this request (must match if we receive
292 struct GNUNET_DNSSTUB_RequestSocket *rs;
295 * Number of bytes in 'reply'.
300 * Original DNS request ID as used by the client.
302 uint16_t original_id;
305 * DNS request ID that we used for forwarding.
317 * Return value from 'main'.
319 static int global_ret;
322 * Handle to our regex announcement for IPv4.
324 static struct GNUNET_REGEX_Announcement *regex4;
327 * Handle to our regex announcement for IPv4.
329 static struct GNUNET_REGEX_Announcement *regex6;
332 * The handle to the configuration used throughout the process
334 static const struct GNUNET_CONFIGURATION_Handle *cfg;
337 * The handle to the helper
339 static struct GNUNET_HELPER_Handle *helper_handle;
342 * Arguments to the exit helper.
344 static char *exit_argv[8];
347 * IPv6 address of our TUN interface.
349 static struct in6_addr exit_ipv6addr;
352 * IPv6 prefix (0..127) from configuration file.
354 static unsigned long long ipv6prefix;
357 * IPv4 address of our TUN interface.
359 static struct in_addr exit_ipv4addr;
362 * IPv4 netmask of our TUN interface.
364 static struct in_addr exit_ipv4mask;
369 static struct GNUNET_STATISTICS_Handle *stats;
374 static struct GNUNET_MESH_Handle *mesh_handle;
377 * This hashmaps contains the mapping from peer, service-descriptor,
378 * source-port and destination-port to a struct TunnelState
380 static struct GNUNET_CONTAINER_MultiHashMap *connections_map;
383 * Heap so we can quickly find "old" connections.
385 static struct GNUNET_CONTAINER_Heap *connections_heap;
388 * If there are at least this many connections, old ones will be removed
390 static unsigned long long max_connections;
393 * This hashmaps saves interesting things about the configured UDP services
395 static struct GNUNET_CONTAINER_MultiHashMap *udp_services;
398 * This hashmaps saves interesting things about the configured TCP services
400 static struct GNUNET_CONTAINER_MultiHashMap *tcp_services;
403 * Array of all open DNS requests from tunnels.
405 static struct TunnelState *tunnels[UINT16_MAX + 1];
408 * Handle to the DNS Stub resolver.
410 static struct GNUNET_DNSSTUB_Context *dnsstub;
413 * Handle for ongoing DHT PUT operations to advertise exit service.
415 static struct GNUNET_DHT_PutHandle *dht_put;
420 static struct GNUNET_DHT_Handle *dht;
423 * Task for doing DHT PUTs to advertise exit service.
425 static GNUNET_SCHEDULER_TaskIdentifier dht_task;
428 * Advertisement message we put into the DHT to advertise us
431 static struct GNUNET_DNS_Advertisement dns_advertisement;
434 * Key we store the DNS advertismenet under.
436 static struct GNUNET_HashCode dht_put_key;
439 * Private key for this peer.
441 static struct GNUNET_CRYPTO_EccPrivateKey *peer_key;
444 * Are we an IPv4-exit?
446 static int ipv4_exit;
449 * Are we an IPv6-exit?
451 static int ipv6_exit;
454 * Do we support IPv4 at all on the TUN interface?
456 static int ipv4_enabled;
459 * Do we support IPv6 at all on the TUN interface?
461 static int ipv6_enabled;
465 * We got a reply from DNS for a request of a MESH tunnel. Send it
466 * via the tunnel (after changing the request ID back).
468 * @param cls the 'struct TunnelState'
469 * @param size number of bytes available in buf
470 * @param buf where to copy the reply
471 * @return number of bytes written to buf
474 transmit_reply_to_mesh (void *cls,
478 struct TunnelState *ts = cls;
482 struct GNUNET_MessageHeader hdr;
483 struct GNUNET_TUN_DnsHeader dns;
485 GNUNET_assert (GNUNET_YES == ts->is_dns);
487 GNUNET_assert (ts->specifics.dns.reply != NULL);
490 ret = sizeof (struct GNUNET_MessageHeader) + ts->specifics.dns.reply_length;
491 GNUNET_assert (ret <= size);
492 hdr.size = htons (ret);
493 hdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_DNS_FROM_INTERNET);
494 memcpy (&dns, ts->specifics.dns.reply, sizeof (dns));
495 dns.id = ts->specifics.dns.original_id;
497 memcpy (&cbuf[off], &hdr, sizeof (hdr));
499 memcpy (&cbuf[off], &dns, sizeof (dns));
501 memcpy (&cbuf[off], &ts->specifics.dns.reply[sizeof (dns)], ts->specifics.dns.reply_length - sizeof (dns));
502 off += ts->specifics.dns.reply_length - sizeof (dns);
503 GNUNET_free (ts->specifics.dns.reply);
504 ts->specifics.dns.reply = NULL;
505 ts->specifics.dns.reply_length = 0;
506 GNUNET_assert (ret == off);
512 * Callback called from DNSSTUB resolver when a resolution
516 * @param rs the socket that received the response
517 * @param dns the response itself
518 * @param r number of bytes in dns
521 process_dns_result (void *cls,
522 struct GNUNET_DNSSTUB_RequestSocket *rs,
523 const struct GNUNET_TUN_DnsHeader *dns,
526 struct TunnelState *ts;
528 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
529 "Processing DNS result from stub resolver\n");
530 GNUNET_assert (NULL == cls);
531 /* Handle case that this is a reply to a request from a MESH DNS tunnel */
532 ts = tunnels[dns->id];
534 (ts->specifics.dns.rs != rs) )
536 LOG (GNUNET_ERROR_TYPE_DEBUG,
537 "Got a response from the stub resolver for DNS request received via MESH!\n");
538 tunnels[dns->id] = NULL;
539 GNUNET_free_non_null (ts->specifics.dns.reply);
540 ts->specifics.dns.reply = GNUNET_malloc (r);
541 ts->specifics.dns.reply_length = r;
542 memcpy (ts->specifics.dns.reply, dns, r);
544 GNUNET_MESH_notify_transmit_ready_cancel (ts->th);
545 ts->th = GNUNET_MESH_notify_transmit_ready (ts->tunnel,
547 GNUNET_TIME_UNIT_FOREVER_REL,
548 sizeof (struct GNUNET_MessageHeader) + r,
549 &transmit_reply_to_mesh,
555 * Process a request via mesh to perform a DNS query.
557 * @param cls closure, NULL
558 * @param tunnel connection to the other end
559 * @param tunnel_ctx pointer to our `struct TunnelState *`
560 * @param message the actual message
562 * @return #GNUNET_OK to keep the connection open,
563 * #GNUNET_SYSERR to close it (signal serious error)
566 receive_dns_request (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
568 const struct GNUNET_MessageHeader *message)
570 struct TunnelState *ts = *tunnel_ctx;
571 const struct GNUNET_TUN_DnsHeader *dns;
572 size_t mlen = ntohs (message->size);
573 size_t dlen = mlen - sizeof (struct GNUNET_MessageHeader);
574 char buf[dlen] GNUNET_ALIGN;
575 struct GNUNET_TUN_DnsHeader *dout;
578 return GNUNET_SYSERR;
579 if (GNUNET_NO == ts->is_dns)
582 return GNUNET_SYSERR;
584 if (GNUNET_SYSERR == ts->is_dns)
586 /* tunnel is DNS from now on */
587 ts->is_dns = GNUNET_YES;
589 if (dlen < sizeof (struct GNUNET_TUN_DnsHeader))
592 return GNUNET_SYSERR;
594 dns = (const struct GNUNET_TUN_DnsHeader *) &message[1];
595 ts->specifics.dns.original_id = dns->id;
596 if (tunnels[ts->specifics.dns.my_id] == ts)
597 tunnels[ts->specifics.dns.my_id] = NULL;
598 ts->specifics.dns.my_id = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
600 tunnels[ts->specifics.dns.my_id] = ts;
601 memcpy (buf, dns, dlen);
602 dout = (struct GNUNET_TUN_DnsHeader *) buf;
603 dout->id = ts->specifics.dns.my_id;
604 ts->specifics.dns.rs = GNUNET_DNSSTUB_resolve2 (dnsstub,
608 if (NULL == ts->specifics.dns.rs)
609 return GNUNET_SYSERR;
615 * Given IP information about a connection, calculate the respective
616 * hash we would use for the 'connections_map'.
618 * @param hash resulting hash
619 * @param ri information about the connection
622 hash_redirect_info (struct GNUNET_HashCode *hash,
623 const struct RedirectInformation *ri)
627 memset (hash, 0, sizeof (struct GNUNET_HashCode));
628 /* the GNUnet hashmap only uses the first sizeof(unsigned int) of the hash,
629 so we put the IP address in there (and hope for few collisions) */
631 switch (ri->remote_address.af)
634 memcpy (off, &ri->remote_address.address.ipv4, sizeof (struct in_addr));
635 off += sizeof (struct in_addr);
638 memcpy (off, &ri->remote_address.address.ipv6, sizeof (struct in6_addr));
639 off += sizeof (struct in_addr);
644 memcpy (off, &ri->remote_address.port, sizeof (uint16_t));
645 off += sizeof (uint16_t);
646 switch (ri->local_address.af)
649 memcpy (off, &ri->local_address.address.ipv4, sizeof (struct in_addr));
650 off += sizeof (struct in_addr);
653 memcpy (off, &ri->local_address.address.ipv6, sizeof (struct in6_addr));
654 off += sizeof (struct in_addr);
659 memcpy (off, &ri->local_address.port, sizeof (uint16_t));
660 off += sizeof (uint16_t);
661 memcpy (off, &ri->remote_address.proto, sizeof (uint8_t));
662 /* off += sizeof (uint8_t); */
667 * Get our connection tracking state. Warns if it does not exists,
668 * refreshes the timestamp if it does exist.
670 * @param af address family
671 * @param protocol IPPROTO_UDP or IPPROTO_TCP
672 * @param destination_ip target IP
673 * @param destination_port target port
674 * @param local_ip local IP
675 * @param local_port local port
676 * @param state_key set to hash's state if non-NULL
677 * @return NULL if we have no tracking information for this tuple
679 static struct TunnelState *
680 get_redirect_state (int af,
682 const void *destination_ip,
683 uint16_t destination_port,
684 const void *local_ip,
686 struct GNUNET_HashCode *state_key)
688 struct RedirectInformation ri;
689 struct GNUNET_HashCode key;
690 struct TunnelState *state;
692 if ( ( (af == AF_INET) && (protocol == IPPROTO_ICMP) ) ||
693 ( (af == AF_INET6) && (protocol == IPPROTO_ICMPV6) ) )
696 destination_port = 0;
699 ri.remote_address.af = af;
701 ri.remote_address.address.ipv4 = *((struct in_addr*) destination_ip);
703 ri.remote_address.address.ipv6 = * ((struct in6_addr*) destination_ip);
704 ri.remote_address.port = destination_port;
705 ri.remote_address.proto = protocol;
706 ri.local_address.af = af;
708 ri.local_address.address.ipv4 = *((struct in_addr*) local_ip);
710 ri.local_address.address.ipv6 = * ((struct in6_addr*) local_ip);
711 ri.local_address.port = local_port;
712 ri.local_address.proto = protocol;
713 hash_redirect_info (&key, &ri);
714 if (NULL != state_key)
716 state = GNUNET_CONTAINER_multihashmap_get (connections_map, &key);
719 /* Mark this connection as freshly used */
720 if (NULL == state_key)
721 GNUNET_CONTAINER_heap_update_cost (connections_heap,
722 state->specifics.tcp_udp.heap_node,
723 GNUNET_TIME_absolute_get ().abs_value_us);
729 * Given a service descriptor and a destination port, find the
730 * respective service entry.
732 * @param service_map map of services (TCP or UDP)
733 * @param desc service descriptor
734 * @param destination_port destination port
735 * @return NULL if we are not aware of such a service
737 static struct LocalService *
738 find_service (struct GNUNET_CONTAINER_MultiHashMap *service_map,
739 const struct GNUNET_HashCode *desc,
740 uint16_t destination_port)
742 char key[sizeof (struct GNUNET_HashCode) + sizeof (uint16_t)];
744 memcpy (&key[0], &destination_port, sizeof (uint16_t));
745 memcpy (&key[sizeof(uint16_t)], desc, sizeof (struct GNUNET_HashCode));
746 return GNUNET_CONTAINER_multihashmap_get (service_map,
747 (struct GNUNET_HashCode *) key);
752 * Free memory associated with a service record.
755 * @param key service descriptor
756 * @param value service record to free
760 free_service_record (void *cls,
761 const struct GNUNET_HashCode *key,
764 struct LocalService *service = value;
766 GNUNET_free_non_null (service->name);
767 GNUNET_free (service);
773 * Given a service descriptor and a destination port, find the
774 * respective service entry.
776 * @param service_map map of services (TCP or UDP)
777 * @param name name of the service
778 * @param destination_port destination port
779 * @param service service information record to store (service->name will be set).
782 store_service (struct GNUNET_CONTAINER_MultiHashMap *service_map,
784 uint16_t destination_port,
785 struct LocalService *service)
787 char key[sizeof (struct GNUNET_HashCode) + sizeof (uint16_t)];
788 struct GNUNET_HashCode desc;
790 GNUNET_CRYPTO_hash (name, strlen (name) + 1, &desc);
791 service->name = GNUNET_strdup (name);
792 memcpy (&key[0], &destination_port, sizeof (uint16_t));
793 memcpy (&key[sizeof(uint16_t)], &desc, sizeof (struct GNUNET_HashCode));
795 GNUNET_CONTAINER_multihashmap_put (service_map,
796 (struct GNUNET_HashCode *) key,
798 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
800 free_service_record (NULL, (struct GNUNET_HashCode *) key, service);
801 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
802 _("Got duplicate service records for `%s:%u'\n"),
804 (unsigned int) destination_port);
810 * MESH is ready to receive a message for the tunnel. Transmit it.
812 * @param cls the 'struct TunnelState'.
813 * @param size number of bytes available in buf
814 * @param buf where to copy the message
815 * @return number of bytes copied to buf
818 send_to_peer_notify_callback (void *cls, size_t size, void *buf)
820 struct TunnelState *s = cls;
821 struct GNUNET_MESH_Tunnel *tunnel = s->tunnel;
822 struct TunnelMessageQueue *tnq;
825 tnq = s->specifics.tcp_udp.head;
830 s->th = GNUNET_MESH_notify_transmit_ready (tunnel,
831 GNUNET_NO /* corking */,
832 GNUNET_TIME_UNIT_FOREVER_REL,
834 &send_to_peer_notify_callback,
838 GNUNET_assert (size >= tnq->len);
839 memcpy (buf, tnq->payload, tnq->len);
841 GNUNET_CONTAINER_DLL_remove (s->specifics.tcp_udp.head,
842 s->specifics.tcp_udp.tail,
845 if (NULL != (tnq = s->specifics.tcp_udp.head))
846 s->th = GNUNET_MESH_notify_transmit_ready (tunnel,
847 GNUNET_NO /* corking */,
848 GNUNET_TIME_UNIT_FOREVER_REL,
850 &send_to_peer_notify_callback,
852 GNUNET_STATISTICS_update (stats,
853 gettext_noop ("# Bytes transmitted via mesh tunnels"),
860 * Send the given packet via the mesh tunnel.
862 * @param s tunnel destination
863 * @param tnq message to queue
866 send_packet_to_mesh_tunnel (struct TunnelState *s,
867 struct TunnelMessageQueue *tnq)
869 struct GNUNET_MESH_Tunnel *mesh_tunnel;
871 mesh_tunnel = s->tunnel;
872 GNUNET_assert (NULL != s);
873 GNUNET_CONTAINER_DLL_insert_tail (s->specifics.tcp_udp.head, s->specifics.tcp_udp.tail, tnq);
875 s->th = GNUNET_MESH_notify_transmit_ready (mesh_tunnel,
876 GNUNET_NO /* cork */,
877 GNUNET_TIME_UNIT_FOREVER_REL,
879 &send_to_peer_notify_callback,
885 * @brief Handles an ICMP packet received from the helper.
887 * @param icmp A pointer to the Packet
888 * @param pktlen number of bytes in 'icmp'
889 * @param af address family (AFINET or AF_INET6)
890 * @param destination_ip destination IP-address of the IP packet (should
891 * be our local address)
892 * @param source_ip original source IP-address of the IP packet (should
893 * be the original destination address)
896 icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp,
899 const void *destination_ip,
900 const void *source_ip)
902 struct TunnelState *state;
903 struct TunnelMessageQueue *tnq;
904 struct GNUNET_EXIT_IcmpToVPNMessage *i2v;
905 const struct GNUNET_TUN_IPv4Header *ipv4;
906 const struct GNUNET_TUN_IPv6Header *ipv6;
907 const struct GNUNET_TUN_UdpHeader *udp;
909 uint16_t source_port;
910 uint16_t destination_port;
914 char sbuf[INET6_ADDRSTRLEN];
915 char dbuf[INET6_ADDRSTRLEN];
916 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
917 "Received ICMP packet going from %s to %s\n",
920 sbuf, sizeof (sbuf)),
923 dbuf, sizeof (dbuf)));
925 if (pktlen < sizeof (struct GNUNET_TUN_IcmpHeader))
932 /* Find out if this is an ICMP packet in response to an existing
933 TCP/UDP packet and if so, figure out ports / protocol of the
934 existing session from the IP data in the ICMP payload */
936 destination_port = 0;
940 protocol = IPPROTO_ICMP;
943 case GNUNET_TUN_ICMPTYPE_ECHO_REPLY:
944 case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST:
946 case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE:
947 case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH:
948 case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED:
950 sizeof (struct GNUNET_TUN_IcmpHeader) +
951 sizeof (struct GNUNET_TUN_IPv4Header) + 8)
957 ipv4 = (const struct GNUNET_TUN_IPv4Header *) &icmp[1];
958 protocol = ipv4->protocol;
959 /* could be TCP or UDP, but both have the ports in the right
960 place, so that doesn't matter here */
961 udp = (const struct GNUNET_TUN_UdpHeader *) &ipv4[1];
962 /* swap ports, as they are from the original message */
963 destination_port = ntohs (udp->source_port);
964 source_port = ntohs (udp->destination_port);
965 /* throw away ICMP payload, won't be useful for the other side anyway */
966 pktlen = sizeof (struct GNUNET_TUN_IcmpHeader);
969 GNUNET_STATISTICS_update (stats,
970 gettext_noop ("# ICMPv4 packets dropped (type not allowed)"),
976 protocol = IPPROTO_ICMPV6;
979 case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE:
980 case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG:
981 case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED:
982 case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM:
984 sizeof (struct GNUNET_TUN_IcmpHeader) +
985 sizeof (struct GNUNET_TUN_IPv6Header) + 8)
991 ipv6 = (const struct GNUNET_TUN_IPv6Header *) &icmp[1];
992 protocol = ipv6->next_header;
993 /* could be TCP or UDP, but both have the ports in the right
994 place, so that doesn't matter here */
995 udp = (const struct GNUNET_TUN_UdpHeader *) &ipv6[1];
996 /* swap ports, as they are from the original message */
997 destination_port = ntohs (udp->source_port);
998 source_port = ntohs (udp->destination_port);
999 /* throw away ICMP payload, won't be useful for the other side anyway */
1000 pktlen = sizeof (struct GNUNET_TUN_IcmpHeader);
1002 case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST:
1003 case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY:
1006 GNUNET_STATISTICS_update (stats,
1007 gettext_noop ("# ICMPv6 packets dropped (type not allowed)"),
1018 state = get_redirect_state (af, IPPROTO_ICMP,
1023 case IPPROTO_ICMPV6:
1024 state = get_redirect_state (af, IPPROTO_ICMPV6,
1030 state = get_redirect_state (af, IPPROTO_UDP,
1038 state = get_redirect_state (af, IPPROTO_TCP,
1046 GNUNET_STATISTICS_update (stats,
1047 gettext_noop ("# ICMP packets dropped (not allowed)"),
1053 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1054 _("ICMP Packet dropped, have no matching connection information\n"));
1057 mlen = sizeof (struct GNUNET_EXIT_IcmpToVPNMessage) + pktlen - sizeof (struct GNUNET_TUN_IcmpHeader);
1058 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueue) + mlen);
1059 tnq->payload = &tnq[1];
1061 i2v = (struct GNUNET_EXIT_IcmpToVPNMessage *) &tnq[1];
1062 i2v->header.size = htons ((uint16_t) mlen);
1063 i2v->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_VPN);
1064 i2v->af = htonl (af);
1065 memcpy (&i2v->icmp_header,
1068 send_packet_to_mesh_tunnel (state, tnq);
1073 * @brief Handles an UDP packet received from the helper.
1075 * @param udp A pointer to the Packet
1076 * @param pktlen number of bytes in 'udp'
1077 * @param af address family (AFINET or AF_INET6)
1078 * @param destination_ip destination IP-address of the IP packet (should
1079 * be our local address)
1080 * @param source_ip original source IP-address of the IP packet (should
1081 * be the original destination address)
1084 udp_from_helper (const struct GNUNET_TUN_UdpHeader *udp,
1087 const void *destination_ip,
1088 const void *source_ip)
1090 struct TunnelState *state;
1091 struct TunnelMessageQueue *tnq;
1092 struct GNUNET_EXIT_UdpReplyMessage *urm;
1096 char sbuf[INET6_ADDRSTRLEN];
1097 char dbuf[INET6_ADDRSTRLEN];
1098 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1099 "Received UDP packet going from %s:%u to %s:%u\n",
1102 sbuf, sizeof (sbuf)),
1103 (unsigned int) ntohs (udp->source_port),
1106 dbuf, sizeof (dbuf)),
1107 (unsigned int) ntohs (udp->destination_port));
1109 if (pktlen < sizeof (struct GNUNET_TUN_UdpHeader))
1115 if (pktlen != ntohs (udp->len))
1121 state = get_redirect_state (af, IPPROTO_UDP,
1123 ntohs (udp->source_port),
1125 ntohs (udp->destination_port),
1129 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1130 _("UDP Packet dropped, have no matching connection information\n"));
1133 mlen = sizeof (struct GNUNET_EXIT_UdpReplyMessage) + pktlen - sizeof (struct GNUNET_TUN_UdpHeader);
1134 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueue) + mlen);
1135 tnq->payload = &tnq[1];
1137 urm = (struct GNUNET_EXIT_UdpReplyMessage *) &tnq[1];
1138 urm->header.size = htons ((uint16_t) mlen);
1139 urm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_UDP_REPLY);
1140 urm->source_port = htons (0);
1141 urm->destination_port = htons (0);
1144 pktlen - sizeof (struct GNUNET_TUN_UdpHeader));
1145 send_packet_to_mesh_tunnel (state, tnq);
1150 * @brief Handles a TCP packet received from the helper.
1152 * @param tcp A pointer to the Packet
1153 * @param pktlen the length of the packet, including its TCP header
1154 * @param af address family (AFINET or AF_INET6)
1155 * @param destination_ip destination IP-address of the IP packet (should
1156 * be our local address)
1157 * @param source_ip original source IP-address of the IP packet (should
1158 * be the original destination address)
1161 tcp_from_helper (const struct GNUNET_TUN_TcpHeader *tcp,
1164 const void *destination_ip,
1165 const void *source_ip)
1167 struct TunnelState *state;
1168 char buf[pktlen] GNUNET_ALIGN;
1169 struct GNUNET_TUN_TcpHeader *mtcp;
1170 struct GNUNET_EXIT_TcpDataMessage *tdm;
1171 struct TunnelMessageQueue *tnq;
1175 char sbuf[INET6_ADDRSTRLEN];
1176 char dbuf[INET6_ADDRSTRLEN];
1177 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1178 "Received TCP packet with %u bytes going from %s:%u to %s:%u\n",
1179 pktlen - sizeof (struct GNUNET_TUN_TcpHeader),
1182 sbuf, sizeof (sbuf)),
1183 (unsigned int) ntohs (tcp->source_port),
1186 dbuf, sizeof (dbuf)),
1187 (unsigned int) ntohs (tcp->destination_port));
1189 if (pktlen < sizeof (struct GNUNET_TUN_TcpHeader))
1195 state = get_redirect_state (af, IPPROTO_TCP,
1197 ntohs (tcp->source_port),
1199 ntohs (tcp->destination_port),
1203 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1204 _("TCP Packet dropped, have no matching connection information\n"));
1208 /* mug port numbers and crc to avoid information leakage;
1209 sender will need to lookup the correct values anyway */
1210 memcpy (buf, tcp, pktlen);
1211 mtcp = (struct GNUNET_TUN_TcpHeader *) buf;
1212 mtcp->source_port = 0;
1213 mtcp->destination_port = 0;
1216 mlen = sizeof (struct GNUNET_EXIT_TcpDataMessage) + (pktlen - sizeof (struct GNUNET_TUN_TcpHeader));
1217 if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1223 tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueue) + mlen);
1224 tnq->payload = &tnq[1];
1226 tdm = (struct GNUNET_EXIT_TcpDataMessage *) &tnq[1];
1227 tdm->header.size = htons ((uint16_t) mlen);
1228 tdm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_DATA_TO_VPN);
1229 tdm->reserved = htonl (0);
1230 memcpy (&tdm->tcp_header,
1233 send_packet_to_mesh_tunnel (state, tnq);
1238 * Receive packets from the helper-process
1241 * @param client unsued
1242 * @param message message received from helper
1245 message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED,
1246 const struct GNUNET_MessageHeader *message)
1248 const struct GNUNET_TUN_Layer2PacketHeader *pkt_tun;
1251 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1252 "Got %u-byte message of type %u from gnunet-helper-exit\n",
1253 ntohs (message->size),
1254 ntohs (message->type));
1255 GNUNET_STATISTICS_update (stats,
1256 gettext_noop ("# Packets received from TUN"),
1258 if (ntohs (message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER)
1263 size = ntohs (message->size);
1264 if (size < sizeof (struct GNUNET_TUN_Layer2PacketHeader) + sizeof (struct GNUNET_MessageHeader))
1269 GNUNET_STATISTICS_update (stats,
1270 gettext_noop ("# Bytes received from TUN"),
1272 pkt_tun = (const struct GNUNET_TUN_Layer2PacketHeader *) &message[1];
1273 size -= sizeof (struct GNUNET_TUN_Layer2PacketHeader) + sizeof (struct GNUNET_MessageHeader);
1274 switch (ntohs (pkt_tun->proto))
1278 const struct GNUNET_TUN_IPv4Header *pkt4;
1280 if (size < sizeof (struct GNUNET_TUN_IPv4Header))
1282 /* Kernel to blame? */
1286 pkt4 = (const struct GNUNET_TUN_IPv4Header *) &pkt_tun[1];
1287 if (size != ntohs (pkt4->total_length))
1289 /* Kernel to blame? */
1293 if (pkt4->header_length * 4 != sizeof (struct GNUNET_TUN_IPv4Header))
1295 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1296 _("IPv4 packet options received. Ignored.\n"));
1300 size -= sizeof (struct GNUNET_TUN_IPv4Header);
1301 switch (pkt4->protocol)
1304 udp_from_helper ((const struct GNUNET_TUN_UdpHeader *) &pkt4[1], size,
1306 &pkt4->destination_address,
1307 &pkt4->source_address);
1310 tcp_from_helper ((const struct GNUNET_TUN_TcpHeader *) &pkt4[1], size,
1312 &pkt4->destination_address,
1313 &pkt4->source_address);
1316 icmp_from_helper ((const struct GNUNET_TUN_IcmpHeader *) &pkt4[1], size,
1318 &pkt4->destination_address,
1319 &pkt4->source_address);
1322 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1323 _("IPv4 packet with unsupported next header %u received. Ignored.\n"),
1324 (int) pkt4->protocol);
1331 const struct GNUNET_TUN_IPv6Header *pkt6;
1333 if (size < sizeof (struct GNUNET_TUN_IPv6Header))
1335 /* Kernel to blame? */
1339 pkt6 = (struct GNUNET_TUN_IPv6Header *) &pkt_tun[1];
1340 if (size != ntohs (pkt6->payload_length) + sizeof (struct GNUNET_TUN_IPv6Header))
1342 /* Kernel to blame? */
1346 size -= sizeof (struct GNUNET_TUN_IPv6Header);
1347 switch (pkt6->next_header)
1350 udp_from_helper ((const struct GNUNET_TUN_UdpHeader *) &pkt6[1], size,
1352 &pkt6->destination_address,
1353 &pkt6->source_address);
1356 tcp_from_helper ((const struct GNUNET_TUN_TcpHeader *) &pkt6[1], size,
1358 &pkt6->destination_address,
1359 &pkt6->source_address);
1361 case IPPROTO_ICMPV6:
1362 icmp_from_helper ((const struct GNUNET_TUN_IcmpHeader *) &pkt6[1], size,
1364 &pkt6->destination_address,
1365 &pkt6->source_address);
1368 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1369 _("IPv6 packet with unsupported next header %d received. Ignored.\n"),
1376 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1377 _("Packet from unknown protocol %u received. Ignored.\n"),
1378 ntohs (pkt_tun->proto));
1386 * We need to create a (unique) fresh local address (IP+port).
1389 * @param af desired address family
1390 * @param proto desired protocol (IPPROTO_UDP or IPPROTO_TCP)
1391 * @param local_address address to initialize
1394 setup_fresh_address (int af,
1396 struct SocketAddress *local_address)
1398 local_address->af = af;
1399 local_address->proto = (uint8_t) proto;
1400 /* default "local" port range is often 32768--61000,
1401 so we pick a random value in that range */
1402 if ( ( (af == AF_INET) && (proto == IPPROTO_ICMP) ) ||
1403 ( (af == AF_INET6) && (proto == IPPROTO_ICMPV6) ) )
1404 local_address->port = 0;
1407 = (uint16_t) 32768 + GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1413 struct in_addr addr;
1414 struct in_addr mask;
1417 addr = exit_ipv4addr;
1418 mask = exit_ipv4mask;
1419 if (0 == ~mask.s_addr)
1421 /* only one valid IP anyway */
1422 local_address->address.ipv4 = addr;
1425 /* Given 192.168.0.1/255.255.0.0, we want a mask
1426 of '192.168.255.255', thus: */
1427 mask.s_addr = addr.s_addr | ~mask.s_addr;
1428 /* Pick random IPv4 address within the subnet, except 'addr' or 'mask' itself */
1431 rnd.s_addr = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1433 local_address->address.ipv4.s_addr = (addr.s_addr | rnd.s_addr) & mask.s_addr;
1435 while ( (local_address->address.ipv4.s_addr == addr.s_addr) ||
1436 (local_address->address.ipv4.s_addr == mask.s_addr) );
1441 struct in6_addr addr;
1442 struct in6_addr mask;
1443 struct in6_addr rnd;
1446 addr = exit_ipv6addr;
1447 GNUNET_assert (ipv6prefix < 128);
1448 if (ipv6prefix == 127)
1450 /* only one valid IP anyway */
1451 local_address->address.ipv6 = addr;
1454 /* Given ABCD::/96, we want a mask of 'ABCD::FFFF:FFFF,
1457 for (i=127;i>=ipv6prefix;i--)
1458 mask.s6_addr[i / 8] |= (1 << (i % 8));
1460 /* Pick random IPv6 address within the subnet, except 'addr' or 'mask' itself */
1465 rnd.s6_addr[i] = (unsigned char) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1467 local_address->address.ipv6.s6_addr[i]
1468 = (addr.s6_addr[i] | rnd.s6_addr[i]) & mask.s6_addr[i];
1471 while ( (0 == memcmp (&local_address->address.ipv6,
1473 sizeof (struct in6_addr))) ||
1474 (0 == memcmp (&local_address->address.ipv6,
1476 sizeof (struct in6_addr))) );
1486 * We are starting a fresh connection (TCP or UDP) and need
1487 * to pick a source port and IP address (within the correct
1488 * range and address family) to associate replies with the
1489 * connection / correct mesh tunnel. This function generates
1490 * a "fresh" source IP and source port number for a connection
1491 * After picking a good source address, this function sets up
1492 * the state in the 'connections_map' and 'connections_heap'
1493 * to allow finding the state when needed later. The function
1494 * also makes sure that we remain within memory limits by
1495 * cleaning up 'old' states.
1497 * @param state skeleton state to setup a record for; should
1498 * 'state->specifics.tcp_udp.ri.remote_address' filled in so that
1499 * this code can determine which AF/protocol is
1500 * going to be used (the 'tunnel' should also
1501 * already be set); after calling this function,
1502 * heap_node and the local_address will be
1503 * also initialized (heap_node != NULL can be
1504 * used to test if a state has been fully setup).
1507 setup_state_record (struct TunnelState *state)
1509 struct GNUNET_HashCode key;
1510 struct TunnelState *s;
1512 /* generate fresh, unique address */
1515 if (NULL == state->specifics.tcp_udp.serv)
1516 setup_fresh_address (state->specifics.tcp_udp.ri.remote_address.af,
1517 state->specifics.tcp_udp.ri.remote_address.proto,
1518 &state->specifics.tcp_udp.ri.local_address);
1520 setup_fresh_address (state->specifics.tcp_udp.serv->address.af,
1521 state->specifics.tcp_udp.serv->address.proto,
1522 &state->specifics.tcp_udp.ri.local_address);
1523 } while (NULL != get_redirect_state (state->specifics.tcp_udp.ri.remote_address.af,
1524 state->specifics.tcp_udp.ri.remote_address.proto,
1525 &state->specifics.tcp_udp.ri.remote_address.address,
1526 state->specifics.tcp_udp.ri.remote_address.port,
1527 &state->specifics.tcp_udp.ri.local_address.address,
1528 state->specifics.tcp_udp.ri.local_address.port,
1531 char buf[INET6_ADDRSTRLEN];
1532 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1533 "Picked local address %s:%u for new connection\n",
1534 inet_ntop (state->specifics.tcp_udp.ri.local_address.af,
1535 &state->specifics.tcp_udp.ri.local_address.address,
1537 (unsigned int) state->specifics.tcp_udp.ri.local_address.port);
1539 state->specifics.tcp_udp.state_key = key;
1540 GNUNET_assert (GNUNET_OK ==
1541 GNUNET_CONTAINER_multihashmap_put (connections_map,
1543 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1544 state->specifics.tcp_udp.heap_node = GNUNET_CONTAINER_heap_insert (connections_heap,
1546 GNUNET_TIME_absolute_get ().abs_value_us);
1547 while (GNUNET_CONTAINER_heap_get_size (connections_heap) > max_connections)
1549 s = GNUNET_CONTAINER_heap_remove_root (connections_heap);
1550 GNUNET_assert (state != s);
1551 s->specifics.tcp_udp.heap_node = NULL;
1552 GNUNET_MESH_tunnel_destroy (s->tunnel);
1553 GNUNET_assert (GNUNET_OK ==
1554 GNUNET_CONTAINER_multihashmap_remove (connections_map,
1555 &s->specifics.tcp_udp.state_key,
1563 * Prepare an IPv4 packet for transmission via the TUN interface.
1564 * Initializes the IP header and calculates checksums (IP+UDP/TCP).
1565 * For UDP, the UDP header will be fully created, whereas for TCP
1566 * only the ports and checksum will be filled in. So for TCP,
1567 * a skeleton TCP header must be part of the provided payload.
1569 * @param payload payload of the packet (starting with UDP payload or
1570 * TCP header, depending on protocol)
1571 * @param payload_length number of bytes in 'payload'
1572 * @param protocol IPPROTO_UDP or IPPROTO_TCP
1573 * @param tcp_header skeleton of the TCP header, NULL for UDP
1574 * @param src_address source address to use (IP and port)
1575 * @param dst_address destination address to use (IP and port)
1576 * @param pkt4 where to write the assembled packet; must
1577 * contain enough space for the IP header, UDP/TCP header
1581 prepare_ipv4_packet (const void *payload, size_t payload_length,
1583 const struct GNUNET_TUN_TcpHeader *tcp_header,
1584 const struct SocketAddress *src_address,
1585 const struct SocketAddress *dst_address,
1586 struct GNUNET_TUN_IPv4Header *pkt4)
1590 len = payload_length;
1594 len += sizeof (struct GNUNET_TUN_UdpHeader);
1597 len += sizeof (struct GNUNET_TUN_TcpHeader);
1598 GNUNET_assert (NULL != tcp_header);
1604 if (len + sizeof (struct GNUNET_TUN_IPv4Header) > UINT16_MAX)
1610 GNUNET_TUN_initialize_ipv4_header (pkt4,
1613 &src_address->address.ipv4,
1614 &dst_address->address.ipv4);
1619 struct GNUNET_TUN_UdpHeader *pkt4_udp = (struct GNUNET_TUN_UdpHeader *) &pkt4[1];
1621 pkt4_udp->source_port = htons (src_address->port);
1622 pkt4_udp->destination_port = htons (dst_address->port);
1623 pkt4_udp->len = htons ((uint16_t) payload_length);
1624 GNUNET_TUN_calculate_udp4_checksum (pkt4,
1626 payload, payload_length);
1627 memcpy (&pkt4_udp[1], payload, payload_length);
1632 struct GNUNET_TUN_TcpHeader *pkt4_tcp = (struct GNUNET_TUN_TcpHeader *) &pkt4[1];
1634 *pkt4_tcp = *tcp_header;
1635 pkt4_tcp->source_port = htons (src_address->port);
1636 pkt4_tcp->destination_port = htons (dst_address->port);
1637 GNUNET_TUN_calculate_tcp4_checksum (pkt4,
1641 memcpy (&pkt4_tcp[1], payload, payload_length);
1651 * Prepare an IPv6 packet for transmission via the TUN interface.
1652 * Initializes the IP header and calculates checksums (IP+UDP/TCP).
1653 * For UDP, the UDP header will be fully created, whereas for TCP
1654 * only the ports and checksum will be filled in. So for TCP,
1655 * a skeleton TCP header must be part of the provided payload.
1657 * @param payload payload of the packet (starting with UDP payload or
1658 * TCP header, depending on protocol)
1659 * @param payload_length number of bytes in 'payload'
1660 * @param protocol IPPROTO_UDP or IPPROTO_TCP
1661 * @param tcp_header skeleton TCP header data to send, NULL for UDP
1662 * @param src_address source address to use (IP and port)
1663 * @param dst_address destination address to use (IP and port)
1664 * @param pkt6 where to write the assembled packet; must
1665 * contain enough space for the IP header, UDP/TCP header
1669 prepare_ipv6_packet (const void *payload, size_t payload_length,
1671 const struct GNUNET_TUN_TcpHeader *tcp_header,
1672 const struct SocketAddress *src_address,
1673 const struct SocketAddress *dst_address,
1674 struct GNUNET_TUN_IPv6Header *pkt6)
1678 len = payload_length;
1682 len += sizeof (struct GNUNET_TUN_UdpHeader);
1685 len += sizeof (struct GNUNET_TUN_TcpHeader);
1691 if (len > UINT16_MAX)
1697 GNUNET_TUN_initialize_ipv6_header (pkt6,
1700 &src_address->address.ipv6,
1701 &dst_address->address.ipv6);
1707 struct GNUNET_TUN_UdpHeader *pkt6_udp = (struct GNUNET_TUN_UdpHeader *) &pkt6[1];
1709 pkt6_udp->source_port = htons (src_address->port);
1710 pkt6_udp->destination_port = htons (dst_address->port);
1711 pkt6_udp->len = htons ((uint16_t) payload_length);
1712 GNUNET_TUN_calculate_udp6_checksum (pkt6,
1716 memcpy (&pkt6_udp[1], payload, payload_length);
1721 struct GNUNET_TUN_TcpHeader *pkt6_tcp = (struct GNUNET_TUN_TcpHeader *) &pkt6[1];
1723 /* memcpy first here as some TCP header fields are initialized this way! */
1724 *pkt6_tcp = *tcp_header;
1725 pkt6_tcp->source_port = htons (src_address->port);
1726 pkt6_tcp->destination_port = htons (dst_address->port);
1727 GNUNET_TUN_calculate_tcp6_checksum (pkt6,
1731 memcpy (&pkt6_tcp[1], payload, payload_length);
1742 * Send a TCP packet via the TUN interface.
1744 * @param destination_address IP and port to use for the TCP packet's destination
1745 * @param source_address IP and port to use for the TCP packet's source
1746 * @param tcp_header header template to use
1747 * @param payload payload of the TCP packet
1748 * @param payload_length number of bytes in 'payload'
1751 send_tcp_packet_via_tun (const struct SocketAddress *destination_address,
1752 const struct SocketAddress *source_address,
1753 const struct GNUNET_TUN_TcpHeader *tcp_header,
1754 const void *payload, size_t payload_length)
1758 GNUNET_STATISTICS_update (stats,
1759 gettext_noop ("# TCP packets sent via TUN"),
1761 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1762 "Sending packet with %u bytes TCP payload via TUN\n",
1763 (unsigned int) payload_length);
1764 len = sizeof (struct GNUNET_MessageHeader) + sizeof (struct GNUNET_TUN_Layer2PacketHeader);
1765 switch (source_address->af)
1768 len += sizeof (struct GNUNET_TUN_IPv4Header);
1771 len += sizeof (struct GNUNET_TUN_IPv6Header);
1777 len += sizeof (struct GNUNET_TUN_TcpHeader);
1778 len += payload_length;
1779 if (len >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1785 char buf[len] GNUNET_ALIGN;
1786 struct GNUNET_MessageHeader *hdr;
1787 struct GNUNET_TUN_Layer2PacketHeader *tun;
1789 hdr = (struct GNUNET_MessageHeader *) buf;
1790 hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
1791 hdr->size = htons (len);
1792 tun = (struct GNUNET_TUN_Layer2PacketHeader*) &hdr[1];
1793 tun->flags = htons (0);
1794 switch (source_address->af)
1798 struct GNUNET_TUN_IPv4Header * ipv4 = (struct GNUNET_TUN_IPv4Header*) &tun[1];
1800 tun->proto = htons (ETH_P_IPV4);
1801 prepare_ipv4_packet (payload, payload_length,
1805 destination_address,
1811 struct GNUNET_TUN_IPv6Header * ipv6 = (struct GNUNET_TUN_IPv6Header*) &tun[1];
1813 tun->proto = htons (ETH_P_IPV6);
1814 prepare_ipv6_packet (payload, payload_length,
1818 destination_address,
1826 if (NULL != helper_handle)
1827 (void) GNUNET_HELPER_send (helper_handle,
1828 (const struct GNUNET_MessageHeader*) buf,
1836 * Process a request via mesh to send a request to a TCP service
1837 * offered by this system.
1839 * @param cls closure, NULL
1840 * @param tunnel connection to the other end
1841 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1842 * @param message the actual message
1844 * @return GNUNET_OK to keep the connection open,
1845 * GNUNET_SYSERR to close it (signal serious error)
1848 receive_tcp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1849 void **tunnel_ctx GNUNET_UNUSED,
1850 const struct GNUNET_MessageHeader *message)
1852 struct TunnelState *state = *tunnel_ctx;
1853 const struct GNUNET_EXIT_TcpServiceStartMessage *start;
1854 uint16_t pkt_len = ntohs (message->size);
1858 GNUNET_break_op (0);
1859 return GNUNET_SYSERR;
1861 if (GNUNET_YES == state->is_dns)
1863 GNUNET_break_op (0);
1864 return GNUNET_SYSERR;
1866 if (GNUNET_SYSERR == state->is_dns)
1868 /* tunnel is UDP/TCP from now on */
1869 state->is_dns = GNUNET_NO;
1871 GNUNET_STATISTICS_update (stats,
1872 gettext_noop ("# TCP service creation requests received via mesh"),
1874 GNUNET_STATISTICS_update (stats,
1875 gettext_noop ("# Bytes received from MESH"),
1876 pkt_len, GNUNET_NO);
1877 /* check that we got at least a valid header */
1878 if (pkt_len < sizeof (struct GNUNET_EXIT_TcpServiceStartMessage))
1880 GNUNET_break_op (0);
1881 return GNUNET_SYSERR;
1883 start = (const struct GNUNET_EXIT_TcpServiceStartMessage*) message;
1884 pkt_len -= sizeof (struct GNUNET_EXIT_TcpServiceStartMessage);
1885 if ( (NULL != state->specifics.tcp_udp.serv) ||
1886 (NULL != state->specifics.tcp_udp.heap_node) )
1888 GNUNET_break_op (0);
1889 return GNUNET_SYSERR;
1891 if (start->tcp_header.off * 4 < sizeof (struct GNUNET_TUN_TcpHeader))
1893 GNUNET_break_op (0);
1894 return GNUNET_SYSERR;
1896 GNUNET_break_op (ntohl (start->reserved) == 0);
1897 /* setup fresh connection */
1898 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1899 "Received data from %s for forwarding to TCP service %s on port %u\n",
1900 GNUNET_i2s (&state->peer),
1901 GNUNET_h2s (&start->service_descriptor),
1902 (unsigned int) ntohs (start->tcp_header.destination_port));
1903 if (NULL == (state->specifics.tcp_udp.serv = find_service (tcp_services, &start->service_descriptor,
1904 ntohs (start->tcp_header.destination_port))))
1906 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1907 _("No service found for %s on port %d!\n"),
1909 ntohs (start->tcp_header.destination_port));
1910 GNUNET_STATISTICS_update (stats,
1911 gettext_noop ("# TCP requests dropped (no such service)"),
1913 return GNUNET_SYSERR;
1915 state->specifics.tcp_udp.ri.remote_address = state->specifics.tcp_udp.serv->address;
1916 setup_state_record (state);
1917 send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address,
1918 &state->specifics.tcp_udp.ri.local_address,
1920 &start[1], pkt_len);
1926 * Process a request to forward TCP data to the Internet via this peer.
1928 * @param cls closure, NULL
1929 * @param tunnel connection to the other end
1930 * @param tunnel_ctx pointer to our 'struct TunnelState *'
1931 * @param message the actual message
1933 * @return GNUNET_OK to keep the connection open,
1934 * GNUNET_SYSERR to close it (signal serious error)
1937 receive_tcp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1938 void **tunnel_ctx GNUNET_UNUSED,
1939 const struct GNUNET_MessageHeader *message)
1941 struct TunnelState *state = *tunnel_ctx;
1942 const struct GNUNET_EXIT_TcpInternetStartMessage *start;
1943 uint16_t pkt_len = ntohs (message->size);
1944 const struct in_addr *v4;
1945 const struct in6_addr *v6;
1946 const void *payload;
1951 GNUNET_break_op (0);
1952 return GNUNET_SYSERR;
1954 if (GNUNET_YES == state->is_dns)
1956 GNUNET_break_op (0);
1957 return GNUNET_SYSERR;
1959 if (GNUNET_SYSERR == state->is_dns)
1961 /* tunnel is UDP/TCP from now on */
1962 state->is_dns = GNUNET_NO;
1964 GNUNET_STATISTICS_update (stats,
1965 gettext_noop ("# Bytes received from MESH"),
1966 pkt_len, GNUNET_NO);
1967 GNUNET_STATISTICS_update (stats,
1968 gettext_noop ("# TCP IP-exit creation requests received via mesh"),
1970 if (pkt_len < sizeof (struct GNUNET_EXIT_TcpInternetStartMessage))
1972 GNUNET_break_op (0);
1973 return GNUNET_SYSERR;
1975 start = (const struct GNUNET_EXIT_TcpInternetStartMessage*) message;
1976 pkt_len -= sizeof (struct GNUNET_EXIT_TcpInternetStartMessage);
1977 if ( (NULL != state->specifics.tcp_udp.serv) ||
1978 (NULL != state->specifics.tcp_udp.heap_node) )
1980 GNUNET_break_op (0);
1981 return GNUNET_SYSERR;
1983 if (start->tcp_header.off * 4 < sizeof (struct GNUNET_TUN_TcpHeader))
1985 GNUNET_break_op (0);
1986 return GNUNET_SYSERR;
1988 af = (int) ntohl (start->af);
1989 state->specifics.tcp_udp.ri.remote_address.af = af;
1993 if (pkt_len < sizeof (struct in_addr))
1995 GNUNET_break_op (0);
1996 return GNUNET_SYSERR;
2000 GNUNET_break_op (0);
2001 return GNUNET_SYSERR;
2003 v4 = (const struct in_addr*) &start[1];
2005 pkt_len -= sizeof (struct in_addr);
2006 state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4;
2009 if (pkt_len < sizeof (struct in6_addr))
2011 GNUNET_break_op (0);
2012 return GNUNET_SYSERR;
2016 GNUNET_break_op (0);
2017 return GNUNET_SYSERR;
2019 v6 = (const struct in6_addr*) &start[1];
2021 pkt_len -= sizeof (struct in6_addr);
2022 state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6;
2025 GNUNET_break_op (0);
2026 return GNUNET_SYSERR;
2029 char buf[INET6_ADDRSTRLEN];
2030 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2031 "Received data from %s for starting TCP stream to %s:%u\n",
2032 GNUNET_i2s (&state->peer),
2034 &state->specifics.tcp_udp.ri.remote_address.address,
2036 (unsigned int) ntohs (start->tcp_header.destination_port));
2038 state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_TCP;
2039 state->specifics.tcp_udp.ri.remote_address.port = ntohs (start->tcp_header.destination_port);
2040 setup_state_record (state);
2041 send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address,
2042 &state->specifics.tcp_udp.ri.local_address,
2050 * Process a request to forward TCP data on an established
2051 * connection via this peer.
2053 * @param cls closure, NULL
2054 * @param tunnel connection to the other end
2055 * @param tunnel_ctx pointer to our 'struct TunnelState *'
2056 * @param message the actual message
2058 * @return GNUNET_OK to keep the connection open,
2059 * GNUNET_SYSERR to close it (signal serious error)
2062 receive_tcp_data (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
2063 void **tunnel_ctx GNUNET_UNUSED,
2064 const struct GNUNET_MessageHeader *message)
2066 struct TunnelState *state = *tunnel_ctx;
2067 const struct GNUNET_EXIT_TcpDataMessage *data;
2068 uint16_t pkt_len = ntohs (message->size);
2070 if (GNUNET_YES == state->is_dns)
2072 GNUNET_break_op (0);
2073 return GNUNET_SYSERR;
2075 if (GNUNET_SYSERR == state->is_dns)
2077 /* tunnel is UDP/TCP from now on */
2078 state->is_dns = GNUNET_NO;
2080 GNUNET_STATISTICS_update (stats,
2081 gettext_noop ("# Bytes received from MESH"),
2082 pkt_len, GNUNET_NO);
2083 GNUNET_STATISTICS_update (stats,
2084 gettext_noop ("# TCP data requests received via mesh"),
2086 if (pkt_len < sizeof (struct GNUNET_EXIT_TcpDataMessage))
2088 GNUNET_break_op (0);
2089 return GNUNET_SYSERR;
2091 data = (const struct GNUNET_EXIT_TcpDataMessage*) message;
2092 pkt_len -= sizeof (struct GNUNET_EXIT_TcpDataMessage);
2093 if ( (NULL == state) ||
2094 (NULL == state->specifics.tcp_udp.heap_node) )
2096 /* connection should have been up! */
2097 GNUNET_STATISTICS_update (stats,
2098 gettext_noop ("# TCP DATA requests dropped (no session)"),
2100 return GNUNET_SYSERR;
2102 if (data->tcp_header.off * 4 < sizeof (struct GNUNET_TUN_TcpHeader))
2104 GNUNET_break_op (0);
2105 return GNUNET_SYSERR;
2108 GNUNET_break_op (ntohl (data->reserved) == 0);
2110 char buf[INET6_ADDRSTRLEN];
2111 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2112 "Received additional %u bytes of data from %s for TCP stream to %s:%u\n",
2114 GNUNET_i2s (&state->peer),
2115 inet_ntop (state->specifics.tcp_udp.ri.remote_address.af,
2116 &state->specifics.tcp_udp.ri.remote_address.address,
2118 (unsigned int) state->specifics.tcp_udp.ri.remote_address.port);
2121 send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address,
2122 &state->specifics.tcp_udp.ri.local_address,
2130 * Send an ICMP packet via the TUN interface.
2132 * @param destination_address IP to use for the ICMP packet's destination
2133 * @param source_address IP to use for the ICMP packet's source
2134 * @param icmp_header ICMP header to send
2135 * @param payload payload of the ICMP packet (does NOT include ICMP header)
2136 * @param payload_length number of bytes of data in payload
2139 send_icmp_packet_via_tun (const struct SocketAddress *destination_address,
2140 const struct SocketAddress *source_address,
2141 const struct GNUNET_TUN_IcmpHeader *icmp_header,
2142 const void *payload, size_t payload_length)
2145 struct GNUNET_TUN_IcmpHeader *icmp;
2147 GNUNET_STATISTICS_update (stats,
2148 gettext_noop ("# ICMP packets sent via TUN"),
2150 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2151 "Sending packet with %u bytes ICMP payload via TUN\n",
2152 (unsigned int) payload_length);
2153 len = sizeof (struct GNUNET_MessageHeader) + sizeof (struct GNUNET_TUN_Layer2PacketHeader);
2154 switch (destination_address->af)
2157 len += sizeof (struct GNUNET_TUN_IPv4Header);
2160 len += sizeof (struct GNUNET_TUN_IPv6Header);
2166 len += sizeof (struct GNUNET_TUN_IcmpHeader);
2167 len += payload_length;
2168 if (len >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
2174 char buf[len] GNUNET_ALIGN;
2175 struct GNUNET_MessageHeader *hdr;
2176 struct GNUNET_TUN_Layer2PacketHeader *tun;
2178 hdr= (struct GNUNET_MessageHeader *) buf;
2179 hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
2180 hdr->size = htons (len);
2181 tun = (struct GNUNET_TUN_Layer2PacketHeader*) &hdr[1];
2182 tun->flags = htons (0);
2183 switch (source_address->af)
2187 struct GNUNET_TUN_IPv4Header * ipv4 = (struct GNUNET_TUN_IPv4Header*) &tun[1];
2189 tun->proto = htons (ETH_P_IPV4);
2190 GNUNET_TUN_initialize_ipv4_header (ipv4,
2192 sizeof (struct GNUNET_TUN_IcmpHeader) + payload_length,
2193 &source_address->address.ipv4,
2194 &destination_address->address.ipv4);
2195 icmp = (struct GNUNET_TUN_IcmpHeader*) &ipv4[1];
2200 struct GNUNET_TUN_IPv6Header * ipv6 = (struct GNUNET_TUN_IPv6Header*) &tun[1];
2202 tun->proto = htons (ETH_P_IPV6);
2203 GNUNET_TUN_initialize_ipv6_header (ipv6,
2205 sizeof (struct GNUNET_TUN_IcmpHeader) + payload_length,
2206 &source_address->address.ipv6,
2207 &destination_address->address.ipv6);
2208 icmp = (struct GNUNET_TUN_IcmpHeader*) &ipv6[1];
2215 *icmp = *icmp_header;
2219 GNUNET_TUN_calculate_icmp_checksum (icmp,
2222 if (NULL != helper_handle)
2223 (void) GNUNET_HELPER_send (helper_handle,
2224 (const struct GNUNET_MessageHeader*) buf,
2232 * Synthesize a plausible ICMP payload for an ICMPv4 error
2233 * response on the given tunnel.
2235 * @param state tunnel information
2236 * @param ipp IPv6 header to fill in (ICMP payload)
2237 * @param udp "UDP" header to fill in (ICMP payload); might actually
2238 * also be the first 8 bytes of the TCP header
2241 make_up_icmpv4_payload (struct TunnelState *state,
2242 struct GNUNET_TUN_IPv4Header *ipp,
2243 struct GNUNET_TUN_UdpHeader *udp)
2245 GNUNET_TUN_initialize_ipv4_header (ipp,
2246 state->specifics.tcp_udp.ri.remote_address.proto,
2247 sizeof (struct GNUNET_TUN_TcpHeader),
2248 &state->specifics.tcp_udp.ri.remote_address.address.ipv4,
2249 &state->specifics.tcp_udp.ri.local_address.address.ipv4);
2250 udp->source_port = htons (state->specifics.tcp_udp.ri.remote_address.port);
2251 udp->destination_port = htons (state->specifics.tcp_udp.ri.local_address.port);
2252 udp->len = htons (0);
2253 udp->crc = htons (0);
2258 * Synthesize a plausible ICMP payload for an ICMPv6 error
2259 * response on the given tunnel.
2261 * @param state tunnel information
2262 * @param ipp IPv6 header to fill in (ICMP payload)
2263 * @param udp "UDP" header to fill in (ICMP payload); might actually
2264 * also be the first 8 bytes of the TCP header
2267 make_up_icmpv6_payload (struct TunnelState *state,
2268 struct GNUNET_TUN_IPv6Header *ipp,
2269 struct GNUNET_TUN_UdpHeader *udp)
2271 GNUNET_TUN_initialize_ipv6_header (ipp,
2272 state->specifics.tcp_udp.ri.remote_address.proto,
2273 sizeof (struct GNUNET_TUN_TcpHeader),
2274 &state->specifics.tcp_udp.ri.remote_address.address.ipv6,
2275 &state->specifics.tcp_udp.ri.local_address.address.ipv6);
2276 udp->source_port = htons (state->specifics.tcp_udp.ri.remote_address.port);
2277 udp->destination_port = htons (state->specifics.tcp_udp.ri.local_address.port);
2278 udp->len = htons (0);
2279 udp->crc = htons (0);
2284 * Process a request to forward ICMP data to the Internet via this peer.
2286 * @param cls closure, NULL
2287 * @param tunnel connection to the other end
2288 * @param tunnel_ctx pointer to our 'struct TunnelState *'
2289 * @param message the actual message
2291 * @return GNUNET_OK to keep the connection open,
2292 * GNUNET_SYSERR to close it (signal serious error)
2295 receive_icmp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
2296 void **tunnel_ctx GNUNET_UNUSED,
2297 const struct GNUNET_MessageHeader *message)
2299 struct TunnelState *state = *tunnel_ctx;
2300 const struct GNUNET_EXIT_IcmpInternetMessage *msg;
2301 uint16_t pkt_len = ntohs (message->size);
2302 const struct in_addr *v4;
2303 const struct in6_addr *v6;
2304 const void *payload;
2305 char buf[sizeof (struct GNUNET_TUN_IPv6Header) + 8] GNUNET_ALIGN;
2308 if (GNUNET_YES == state->is_dns)
2310 GNUNET_break_op (0);
2311 return GNUNET_SYSERR;
2313 if (GNUNET_SYSERR == state->is_dns)
2315 /* tunnel is UDP/TCP from now on */
2316 state->is_dns = GNUNET_NO;
2318 GNUNET_STATISTICS_update (stats,
2319 gettext_noop ("# Bytes received from MESH"),
2320 pkt_len, GNUNET_NO);
2321 GNUNET_STATISTICS_update (stats,
2322 gettext_noop ("# ICMP IP-exit requests received via mesh"),
2324 if (pkt_len < sizeof (struct GNUNET_EXIT_IcmpInternetMessage))
2326 GNUNET_break_op (0);
2327 return GNUNET_SYSERR;
2329 msg = (const struct GNUNET_EXIT_IcmpInternetMessage*) message;
2330 pkt_len -= sizeof (struct GNUNET_EXIT_IcmpInternetMessage);
2332 af = (int) ntohl (msg->af);
2333 if ( (NULL != state->specifics.tcp_udp.heap_node) &&
2334 (af != state->specifics.tcp_udp.ri.remote_address.af) )
2336 /* other peer switched AF on this tunnel; not allowed */
2337 GNUNET_break_op (0);
2338 return GNUNET_SYSERR;
2344 if (pkt_len < sizeof (struct in_addr))
2346 GNUNET_break_op (0);
2347 return GNUNET_SYSERR;
2351 GNUNET_break_op (0);
2352 return GNUNET_SYSERR;
2354 v4 = (const struct in_addr*) &msg[1];
2356 pkt_len -= sizeof (struct in_addr);
2357 state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4;
2358 if (NULL == state->specifics.tcp_udp.heap_node)
2360 state->specifics.tcp_udp.ri.remote_address.af = af;
2361 state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_ICMP;
2362 setup_state_record (state);
2364 /* check that ICMP type is something we want to support
2365 and possibly make up payload! */
2366 switch (msg->icmp_header.type)
2368 case GNUNET_TUN_ICMPTYPE_ECHO_REPLY:
2369 case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST:
2371 case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE:
2372 case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH:
2373 case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED:
2376 GNUNET_break_op (0);
2377 return GNUNET_SYSERR;
2379 /* make up payload */
2381 struct GNUNET_TUN_IPv4Header *ipp = (struct GNUNET_TUN_IPv4Header *) buf;
2382 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1];
2384 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
2385 pkt_len = sizeof (struct GNUNET_TUN_IPv4Header) + 8;
2386 make_up_icmpv4_payload (state,
2393 GNUNET_break_op (0);
2394 GNUNET_STATISTICS_update (stats,
2395 gettext_noop ("# ICMPv4 packets dropped (type not allowed)"),
2397 return GNUNET_SYSERR;
2402 if (pkt_len < sizeof (struct in6_addr))
2404 GNUNET_break_op (0);
2405 return GNUNET_SYSERR;
2409 GNUNET_break_op (0);
2410 return GNUNET_SYSERR;
2412 v6 = (const struct in6_addr*) &msg[1];
2414 pkt_len -= sizeof (struct in6_addr);
2415 state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6;
2416 if (NULL == state->specifics.tcp_udp.heap_node)
2418 state->specifics.tcp_udp.ri.remote_address.af = af;
2419 state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_ICMPV6;
2420 setup_state_record (state);
2422 /* check that ICMP type is something we want to support
2423 and possibly make up payload! */
2424 switch (msg->icmp_header.type)
2426 case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY:
2427 case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST:
2429 case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE:
2430 case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG:
2431 case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED:
2432 case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM:
2435 GNUNET_break_op (0);
2436 return GNUNET_SYSERR;
2438 /* make up payload */
2440 struct GNUNET_TUN_IPv6Header *ipp = (struct GNUNET_TUN_IPv6Header *) buf;
2441 struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1];
2443 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
2444 pkt_len = sizeof (struct GNUNET_TUN_IPv6Header) + 8;
2445 make_up_icmpv6_payload (state,
2452 GNUNET_break_op (0);
2453 GNUNET_STATISTICS_update (stats,
2454 gettext_noop ("# ICMPv6 packets dropped (type not allowed)"),
2456 return GNUNET_SYSERR;
2462 GNUNET_break_op (0);
2463 return GNUNET_SYSERR;
2467 char buf[INET6_ADDRSTRLEN];
2468 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2469 "Received ICMP data from %s for forwarding to %s\n",
2470 GNUNET_i2s (&state->peer),
2472 &state->specifics.tcp_udp.ri.remote_address.address,
2473 buf, sizeof (buf)));
2475 send_icmp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address,
2476 &state->specifics.tcp_udp.ri.local_address,
2484 * Setup ICMP payload for ICMP error messages. Called
2485 * for both IPv4 and IPv6 addresses.
2487 * @param state context for creating the IP Packet
2488 * @param buf where to create the payload, has at least
2489 * sizeof (struct GNUNET_TUN_IPv6Header) + 8 bytes
2490 * @return number of bytes of payload we created in buf
2493 make_up_icmp_service_payload (struct TunnelState *state,
2496 switch (state->specifics.tcp_udp.serv->address.af)
2500 struct GNUNET_TUN_IPv4Header *ipv4;
2501 struct GNUNET_TUN_UdpHeader *udp;
2503 ipv4 = (struct GNUNET_TUN_IPv4Header *)buf;
2504 udp = (struct GNUNET_TUN_UdpHeader *) &ipv4[1];
2505 make_up_icmpv4_payload (state,
2508 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
2509 return sizeof (struct GNUNET_TUN_IPv4Header) + 8;
2514 struct GNUNET_TUN_IPv6Header *ipv6;
2515 struct GNUNET_TUN_UdpHeader *udp;
2517 ipv6 = (struct GNUNET_TUN_IPv6Header *)buf;
2518 udp = (struct GNUNET_TUN_UdpHeader *) &ipv6[1];
2519 make_up_icmpv6_payload (state,
2522 GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
2523 return sizeof (struct GNUNET_TUN_IPv6Header) + 8;
2534 * Process a request via mesh to send ICMP data to a service
2535 * offered by this system.
2537 * @param cls closure, NULL
2538 * @param tunnel connection to the other end
2539 * @param tunnel_ctx pointer to our 'struct TunnelState *'
2540 * @param message the actual message
2542 * @return GNUNET_OK to keep the connection open,
2543 * GNUNET_SYSERR to close it (signal serious error)
2546 receive_icmp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
2548 const struct GNUNET_MessageHeader *message)
2550 struct TunnelState *state = *tunnel_ctx;
2551 const struct GNUNET_EXIT_IcmpServiceMessage *msg;
2552 uint16_t pkt_len = ntohs (message->size);
2553 struct GNUNET_TUN_IcmpHeader icmp;
2554 char buf[sizeof (struct GNUNET_TUN_IPv6Header) + 8] GNUNET_ALIGN;
2555 const void *payload;
2557 if (GNUNET_YES == state->is_dns)
2559 GNUNET_break_op (0);
2560 return GNUNET_SYSERR;
2562 if (GNUNET_SYSERR == state->is_dns)
2564 /* tunnel is UDP/TCP from now on */
2565 state->is_dns = GNUNET_NO;
2567 GNUNET_STATISTICS_update (stats,
2568 gettext_noop ("# Bytes received from MESH"),
2569 pkt_len, GNUNET_NO);
2570 GNUNET_STATISTICS_update (stats,
2571 gettext_noop ("# ICMP service requests received via mesh"),
2573 /* check that we got at least a valid header */
2574 if (pkt_len < sizeof (struct GNUNET_EXIT_IcmpServiceMessage))
2576 GNUNET_break_op (0);
2577 return GNUNET_SYSERR;
2579 msg = (const struct GNUNET_EXIT_IcmpServiceMessage*) message;
2580 pkt_len -= sizeof (struct GNUNET_EXIT_IcmpServiceMessage);
2581 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2582 "Received data from %s for forwarding to ICMP service %s\n",
2583 GNUNET_i2s (&state->peer),
2584 GNUNET_h2s (&msg->service_descriptor));
2585 if (NULL == state->specifics.tcp_udp.serv)
2587 /* first packet to service must not be ICMP (cannot determine service!) */
2588 GNUNET_break_op (0);
2589 return GNUNET_SYSERR;
2591 icmp = msg->icmp_header;
2593 state->specifics.tcp_udp.ri.remote_address = state->specifics.tcp_udp.serv->address;
2594 setup_state_record (state);
2596 /* check that ICMP type is something we want to support,
2597 perform ICMP PT if needed ans possibly make up payload */
2601 switch (msg->icmp_header.type)
2603 case GNUNET_TUN_ICMPTYPE_ECHO_REPLY:
2604 if (state->specifics.tcp_udp.serv->address.af == AF_INET6)
2605 icmp.type = GNUNET_TUN_ICMPTYPE6_ECHO_REPLY;
2607 case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST:
2608 if (state->specifics.tcp_udp.serv->address.af == AF_INET6)
2609 icmp.type = GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST;
2611 case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE:
2612 if (state->specifics.tcp_udp.serv->address.af == AF_INET6)
2613 icmp.type = GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE;
2616 GNUNET_break_op (0);
2617 return GNUNET_SYSERR;
2620 pkt_len = make_up_icmp_service_payload (state, buf);
2622 case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED:
2623 if (state->specifics.tcp_udp.serv->address.af == AF_INET6)
2624 icmp.type = GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED;
2627 GNUNET_break_op (0);
2628 return GNUNET_SYSERR;
2631 pkt_len = make_up_icmp_service_payload (state, buf);
2633 case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH:
2634 if (state->specifics.tcp_udp.serv->address.af == AF_INET6)
2636 GNUNET_STATISTICS_update (stats,
2637 gettext_noop ("# ICMPv4 packets dropped (impossible PT to v6)"),
2643 GNUNET_break_op (0);
2644 return GNUNET_SYSERR;
2647 pkt_len = make_up_icmp_service_payload (state, buf);
2650 GNUNET_break_op (0);
2651 GNUNET_STATISTICS_update (stats,
2652 gettext_noop ("# ICMPv4 packets dropped (type not allowed)"),
2654 return GNUNET_SYSERR;
2656 /* end of AF_INET */
2659 switch (msg->icmp_header.type)
2661 case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY:
2662 if (state->specifics.tcp_udp.serv->address.af == AF_INET)
2663 icmp.type = GNUNET_TUN_ICMPTYPE_ECHO_REPLY;
2665 case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST:
2666 if (state->specifics.tcp_udp.serv->address.af == AF_INET)
2667 icmp.type = GNUNET_TUN_ICMPTYPE_ECHO_REQUEST;
2669 case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE:
2670 if (state->specifics.tcp_udp.serv->address.af == AF_INET)
2671 icmp.type = GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE;
2674 GNUNET_break_op (0);
2675 return GNUNET_SYSERR;
2678 pkt_len = make_up_icmp_service_payload (state, buf);
2680 case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED:
2681 if (state->specifics.tcp_udp.serv->address.af == AF_INET)
2682 icmp.type = GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED;
2685 GNUNET_break_op (0);
2686 return GNUNET_SYSERR;
2689 pkt_len = make_up_icmp_service_payload (state, buf);
2691 case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG:
2692 case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM:
2693 if (state->specifics.tcp_udp.serv->address.af == AF_INET)
2695 GNUNET_STATISTICS_update (stats,
2696 gettext_noop ("# ICMPv6 packets dropped (impossible PT to v4)"),
2702 GNUNET_break_op (0);
2703 return GNUNET_SYSERR;
2706 pkt_len = make_up_icmp_service_payload (state, buf);
2709 GNUNET_break_op (0);
2710 GNUNET_STATISTICS_update (stats,
2711 gettext_noop ("# ICMPv6 packets dropped (type not allowed)"),
2713 return GNUNET_SYSERR;
2715 /* end of AF_INET6 */
2718 GNUNET_break_op (0);
2719 return GNUNET_SYSERR;
2722 send_icmp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address,
2723 &state->specifics.tcp_udp.ri.local_address,
2731 * Send a UDP packet via the TUN interface.
2733 * @param destination_address IP and port to use for the UDP packet's destination
2734 * @param source_address IP and port to use for the UDP packet's source
2735 * @param payload payload of the UDP packet (does NOT include UDP header)
2736 * @param payload_length number of bytes of data in payload
2739 send_udp_packet_via_tun (const struct SocketAddress *destination_address,
2740 const struct SocketAddress *source_address,
2741 const void *payload, size_t payload_length)
2745 GNUNET_STATISTICS_update (stats,
2746 gettext_noop ("# UDP packets sent via TUN"),
2748 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2749 "Sending packet with %u bytes UDP payload via TUN\n",
2750 (unsigned int) payload_length);
2751 len = sizeof (struct GNUNET_MessageHeader) + sizeof (struct GNUNET_TUN_Layer2PacketHeader);
2752 switch (source_address->af)
2755 len += sizeof (struct GNUNET_TUN_IPv4Header);
2758 len += sizeof (struct GNUNET_TUN_IPv6Header);
2764 len += sizeof (struct GNUNET_TUN_UdpHeader);
2765 len += payload_length;
2766 if (len >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
2772 char buf[len] GNUNET_ALIGN;
2773 struct GNUNET_MessageHeader *hdr;
2774 struct GNUNET_TUN_Layer2PacketHeader *tun;
2776 hdr= (struct GNUNET_MessageHeader *) buf;
2777 hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
2778 hdr->size = htons (len);
2779 tun = (struct GNUNET_TUN_Layer2PacketHeader*) &hdr[1];
2780 tun->flags = htons (0);
2781 switch (source_address->af)
2785 struct GNUNET_TUN_IPv4Header * ipv4 = (struct GNUNET_TUN_IPv4Header*) &tun[1];
2787 tun->proto = htons (ETH_P_IPV4);
2788 prepare_ipv4_packet (payload, payload_length,
2792 destination_address,
2798 struct GNUNET_TUN_IPv6Header * ipv6 = (struct GNUNET_TUN_IPv6Header*) &tun[1];
2800 tun->proto = htons (ETH_P_IPV6);
2801 prepare_ipv6_packet (payload, payload_length,
2805 destination_address,
2813 if (NULL != helper_handle)
2814 (void) GNUNET_HELPER_send (helper_handle,
2815 (const struct GNUNET_MessageHeader*) buf,
2823 * Process a request to forward UDP data to the Internet via this peer.
2825 * @param cls closure, NULL
2826 * @param tunnel connection to the other end
2827 * @param tunnel_ctx pointer to our 'struct TunnelState *'
2828 * @param message the actual message
2830 * @return GNUNET_OK to keep the connection open,
2831 * GNUNET_SYSERR to close it (signal serious error)
2834 receive_udp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
2835 void **tunnel_ctx GNUNET_UNUSED,
2836 const struct GNUNET_MessageHeader *message)
2838 struct TunnelState *state = *tunnel_ctx;
2839 const struct GNUNET_EXIT_UdpInternetMessage *msg;
2840 uint16_t pkt_len = ntohs (message->size);
2841 const struct in_addr *v4;
2842 const struct in6_addr *v6;
2843 const void *payload;
2846 if (GNUNET_YES == state->is_dns)
2848 GNUNET_break_op (0);
2849 return GNUNET_SYSERR;
2851 if (GNUNET_SYSERR == state->is_dns)
2853 /* tunnel is UDP/TCP from now on */
2854 state->is_dns = GNUNET_NO;
2856 GNUNET_STATISTICS_update (stats,
2857 gettext_noop ("# Bytes received from MESH"),
2858 pkt_len, GNUNET_NO);
2859 GNUNET_STATISTICS_update (stats,
2860 gettext_noop ("# UDP IP-exit requests received via mesh"),
2862 if (pkt_len < sizeof (struct GNUNET_EXIT_UdpInternetMessage))
2864 GNUNET_break_op (0);
2865 return GNUNET_SYSERR;
2867 msg = (const struct GNUNET_EXIT_UdpInternetMessage*) message;
2868 pkt_len -= sizeof (struct GNUNET_EXIT_UdpInternetMessage);
2869 af = (int) ntohl (msg->af);
2870 state->specifics.tcp_udp.ri.remote_address.af = af;
2874 if (pkt_len < sizeof (struct in_addr))
2876 GNUNET_break_op (0);
2877 return GNUNET_SYSERR;
2881 GNUNET_break_op (0);
2882 return GNUNET_SYSERR;
2884 v4 = (const struct in_addr*) &msg[1];
2886 pkt_len -= sizeof (struct in_addr);
2887 state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4;
2890 if (pkt_len < sizeof (struct in6_addr))
2892 GNUNET_break_op (0);
2893 return GNUNET_SYSERR;
2897 GNUNET_break_op (0);
2898 return GNUNET_SYSERR;
2900 v6 = (const struct in6_addr*) &msg[1];
2902 pkt_len -= sizeof (struct in6_addr);
2903 state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6;
2906 GNUNET_break_op (0);
2907 return GNUNET_SYSERR;
2910 char buf[INET6_ADDRSTRLEN];
2911 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2912 "Received data from %s for forwarding to UDP %s:%u\n",
2913 GNUNET_i2s (&state->peer),
2915 &state->specifics.tcp_udp.ri.remote_address.address,
2917 (unsigned int) ntohs (msg->destination_port));
2919 state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_UDP;
2920 state->specifics.tcp_udp.ri.remote_address.port = msg->destination_port;
2921 if (NULL == state->specifics.tcp_udp.heap_node)
2922 setup_state_record (state);
2923 if (0 != ntohs (msg->source_port))
2924 state->specifics.tcp_udp.ri.local_address.port = msg->source_port;
2925 send_udp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address,
2926 &state->specifics.tcp_udp.ri.local_address,
2933 * Process a request via mesh to send a request to a UDP service
2934 * offered by this system.
2936 * @param cls closure, NULL
2937 * @param tunnel connection to the other end
2938 * @param tunnel_ctx pointer to our 'struct TunnelState *'
2939 * @param message the actual message
2941 * @return GNUNET_OK to keep the connection open,
2942 * GNUNET_SYSERR to close it (signal serious error)
2945 receive_udp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
2947 const struct GNUNET_MessageHeader *message)
2949 struct TunnelState *state = *tunnel_ctx;
2950 const struct GNUNET_EXIT_UdpServiceMessage *msg;
2951 uint16_t pkt_len = ntohs (message->size);
2953 if (GNUNET_YES == state->is_dns)
2955 GNUNET_break_op (0);
2956 return GNUNET_SYSERR;
2958 if (GNUNET_SYSERR == state->is_dns)
2960 /* tunnel is UDP/TCP from now on */
2961 state->is_dns = GNUNET_NO;
2963 GNUNET_STATISTICS_update (stats,
2964 gettext_noop ("# Bytes received from MESH"),
2965 pkt_len, GNUNET_NO);
2966 GNUNET_STATISTICS_update (stats,
2967 gettext_noop ("# UDP service requests received via mesh"),
2969 /* check that we got at least a valid header */
2970 if (pkt_len < sizeof (struct GNUNET_EXIT_UdpServiceMessage))
2972 GNUNET_break_op (0);
2973 return GNUNET_SYSERR;
2975 msg = (const struct GNUNET_EXIT_UdpServiceMessage*) message;
2976 pkt_len -= sizeof (struct GNUNET_EXIT_UdpServiceMessage);
2977 LOG (GNUNET_ERROR_TYPE_DEBUG,
2978 "Received data from %s for forwarding to UDP service %s on port %u\n",
2979 GNUNET_i2s (&state->peer),
2980 GNUNET_h2s (&msg->service_descriptor),
2981 (unsigned int) ntohs (msg->destination_port));
2982 if (NULL == (state->specifics.tcp_udp.serv = find_service (udp_services, &msg->service_descriptor,
2983 ntohs (msg->destination_port))))
2985 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2986 _("No service found for %s on port %d!\n"),
2988 ntohs (msg->destination_port));
2989 GNUNET_STATISTICS_update (stats,
2990 gettext_noop ("# UDP requests dropped (no such service)"),
2992 return GNUNET_SYSERR;
2994 state->specifics.tcp_udp.ri.remote_address = state->specifics.tcp_udp.serv->address;
2995 setup_state_record (state);
2996 if (0 != ntohs (msg->source_port))
2997 state->specifics.tcp_udp.ri.local_address.port = msg->source_port;
2998 send_udp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address,
2999 &state->specifics.tcp_udp.ri.local_address,
3006 * Callback from GNUNET_MESH for new tunnels.
3008 * @param cls closure
3009 * @param tunnel new handle to the tunnel
3010 * @param initiator peer that started the tunnel
3011 * @param port destination port
3012 * @return initial tunnel context for the tunnel
3015 new_tunnel (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
3016 const struct GNUNET_PeerIdentity *initiator, uint32_t port)
3018 struct TunnelState *s = GNUNET_new (struct TunnelState);
3020 s->is_dns = GNUNET_SYSERR;
3021 s->peer = *initiator;
3022 GNUNET_STATISTICS_update (stats,
3023 gettext_noop ("# Inbound MESH tunnels created"),
3025 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3026 "Received inbound tunnel from `%s'\n",
3027 GNUNET_i2s (initiator));
3034 * Function called by mesh whenever an inbound tunnel is destroyed.
3035 * Should clean up any associated state.
3037 * @param cls closure (set from GNUNET_MESH_connect)
3038 * @param tunnel connection to the other end (henceforth invalid)
3039 * @param tunnel_ctx place where local state associated
3040 * with the tunnel is stored
3043 clean_tunnel (void *cls GNUNET_UNUSED, const struct GNUNET_MESH_Tunnel *tunnel,
3046 struct TunnelState *s = tunnel_ctx;
3047 struct TunnelMessageQueue *tnq;
3049 LOG (GNUNET_ERROR_TYPE_DEBUG,
3050 "Tunnel destroyed\n");
3051 if (GNUNET_SYSERR == s->is_dns)
3056 if (GNUNET_YES == s->is_dns)
3058 if (tunnels[s->specifics.dns.my_id] == s)
3059 tunnels[s->specifics.dns.my_id] = NULL;
3060 GNUNET_free_non_null (s->specifics.dns.reply);
3064 while (NULL != (tnq = s->specifics.tcp_udp.head))
3066 GNUNET_CONTAINER_DLL_remove (s->specifics.tcp_udp.head,
3067 s->specifics.tcp_udp.tail,
3071 if (NULL != s->specifics.tcp_udp.heap_node)
3073 GNUNET_assert (GNUNET_YES ==
3074 GNUNET_CONTAINER_multihashmap_remove (connections_map,
3075 &s->specifics.tcp_udp.state_key,
3077 GNUNET_CONTAINER_heap_remove_node (s->specifics.tcp_udp.heap_node);
3078 s->specifics.tcp_udp.heap_node = NULL;
3083 GNUNET_MESH_notify_transmit_ready_cancel (s->th);
3091 * Function that frees everything from a hashmap
3095 * @param value value to free
3098 free_iterate (void *cls GNUNET_UNUSED,
3099 const struct GNUNET_HashCode * hash GNUNET_UNUSED, void *value)
3101 GNUNET_free (value);
3107 * Function scheduled as very last function, cleans up after us
3110 cleanup (void *cls GNUNET_UNUSED,
3111 const struct GNUNET_SCHEDULER_TaskContext *tskctx)
3115 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3116 "Exit service is shutting down now\n");
3118 if (NULL != helper_handle)
3120 GNUNET_HELPER_stop (helper_handle, GNUNET_NO);
3121 helper_handle = NULL;
3125 GNUNET_REGEX_announce_cancel (regex4);
3130 GNUNET_REGEX_announce_cancel (regex6);
3133 if (NULL != mesh_handle)
3135 GNUNET_MESH_disconnect (mesh_handle);
3138 if (NULL != connections_map)
3140 GNUNET_CONTAINER_multihashmap_iterate (connections_map, &free_iterate, NULL);
3141 GNUNET_CONTAINER_multihashmap_destroy (connections_map);
3142 connections_map = NULL;
3144 if (NULL != connections_heap)
3146 GNUNET_CONTAINER_heap_destroy (connections_heap);
3147 connections_heap = NULL;
3149 if (NULL != tcp_services)
3151 GNUNET_CONTAINER_multihashmap_iterate (tcp_services, &free_service_record, NULL);
3152 GNUNET_CONTAINER_multihashmap_destroy (tcp_services);
3153 tcp_services = NULL;
3155 if (NULL != udp_services)
3157 GNUNET_CONTAINER_multihashmap_iterate (udp_services, &free_service_record, NULL);
3158 GNUNET_CONTAINER_multihashmap_destroy (udp_services);
3159 udp_services = NULL;
3161 if (NULL != dnsstub)
3163 GNUNET_DNSSTUB_stop (dnsstub);
3166 if (NULL != peer_key)
3168 GNUNET_free (peer_key);
3171 if (GNUNET_SCHEDULER_NO_TASK != dht_task)
3173 GNUNET_SCHEDULER_cancel (dht_task);
3174 dht_task = GNUNET_SCHEDULER_NO_TASK;
3176 if (NULL != dht_put)
3178 GNUNET_DHT_put_cancel (dht_put);
3183 GNUNET_DHT_disconnect (dht);
3188 GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
3192 GNUNET_free_non_null (exit_argv[i]);
3197 * Add services to the service map.
3199 * @param proto IPPROTO_TCP or IPPROTO_UDP
3200 * @param cpy copy of the service descriptor (can be mutilated)
3201 * @param name DNS name of the service
3204 add_services (int proto,
3211 struct LocalService *serv;
3213 for (redirect = strtok (cpy, " "); redirect != NULL;
3214 redirect = strtok (NULL, " "))
3216 if (NULL == (hostname = strstr (redirect, ":")))
3218 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3219 "option `%s' for domain `%s' is not formatted correctly!\n",
3226 if (NULL == (hostport = strstr (hostname, ":")))
3228 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3229 "option `%s' for domain `%s' is not formatted correctly!\n",
3237 int local_port = atoi (redirect);
3238 int remote_port = atoi (hostport);
3240 if (!((local_port > 0) && (local_port < 65536)))
3242 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3243 "`%s' is not a valid port number (for domain `%s')!", redirect,
3247 if (!((remote_port > 0) && (remote_port < 65536)))
3249 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3250 "`%s' is not a valid port number (for domain `%s')!", hostport,
3255 serv = GNUNET_new (struct LocalService);
3256 serv->address.proto = proto;
3257 serv->my_port = (uint16_t) local_port;
3258 serv->address.port = remote_port;
3259 if (0 == strcmp ("localhost4", hostname))
3261 const char *ip4addr = exit_argv[5];
3263 serv->address.af = AF_INET;
3264 GNUNET_assert (1 == inet_pton (AF_INET, ip4addr, &serv->address.address.ipv4));
3266 else if (0 == strcmp ("localhost6", hostname))
3268 const char *ip6addr = exit_argv[3];
3270 serv->address.af = AF_INET6;
3271 GNUNET_assert (1 == inet_pton (AF_INET6, ip6addr, &serv->address.address.ipv6));
3275 struct addrinfo *res;
3278 ret = getaddrinfo (hostname, NULL, NULL, &res);
3279 if ( (ret != 0) || (res == NULL) )
3281 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3282 _("No addresses found for hostname `%s' of service `%s'!\n"),
3289 serv->address.af = res->ai_family;
3290 switch (res->ai_family)
3295 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3296 _("Service `%s' configured for IPv4, but IPv4 is disabled!\n"),
3302 serv->address.address.ipv4 = ((struct sockaddr_in *) res->ai_addr)->sin_addr;
3307 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3308 _("Service `%s' configured for IPv4, but IPv4 is disabled!\n"),
3314 serv->address.address.ipv6 = ((struct sockaddr_in6 *) res->ai_addr)->sin6_addr;
3318 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3319 _("No IP addresses found for hostname `%s' of service `%s'!\n"),
3327 store_service ((IPPROTO_UDP == proto) ? udp_services : tcp_services,
3336 * Reads the configuration servicecfg and populates udp_services
3339 * @param section name of section in config, equal to hostname
3342 read_service_conf (void *cls GNUNET_UNUSED, const char *section)
3346 if ((strlen (section) < 8) ||
3347 (0 != strcmp (".gnunet.", section + (strlen (section) - 8))))
3350 GNUNET_CONFIGURATION_get_value_string (cfg, section, "UDP_REDIRECTS",
3353 add_services (IPPROTO_UDP, cpy, section);
3357 GNUNET_CONFIGURATION_get_value_string (cfg, section, "TCP_REDIRECTS",
3360 add_services (IPPROTO_TCP, cpy, section);
3367 * We are running a DNS exit service, advertise it in the
3368 * DHT. This task is run periodically to do the DHT PUT.
3370 * @param cls closure
3371 * @param tc scheduler context
3374 do_dht_put (void *cls,
3375 const struct GNUNET_SCHEDULER_TaskContext *tc);
3379 * Function called when the DHT PUT operation is complete.
3380 * Schedules the next PUT.
3382 * @param cls closure, NULL
3383 * @param success #GNUNET_OK if the operation worked (unused)
3386 dht_put_cont (void *cls,
3390 dht_task = GNUNET_SCHEDULER_add_delayed (DHT_PUT_FREQUENCY,
3397 * We are running a DNS exit service, advertise it in the
3398 * DHT. This task is run periodically to do the DHT PUT.
3400 * @param cls closure
3401 * @param tc scheduler context
3404 do_dht_put (void *cls,
3405 const struct GNUNET_SCHEDULER_TaskContext *tc)
3407 struct GNUNET_TIME_Absolute expiration;
3409 dht_task = GNUNET_SCHEDULER_NO_TASK;
3410 expiration = GNUNET_TIME_absolute_ntoh (dns_advertisement.expiration_time);
3411 if (GNUNET_TIME_absolute_get_remaining (expiration).rel_value_us <
3412 GNUNET_TIME_UNIT_HOURS.rel_value_us)
3414 /* refresh advertisement */
3415 expiration = GNUNET_TIME_relative_to_absolute (DNS_ADVERTISEMENT_TIMEOUT);
3416 dns_advertisement.expiration_time = GNUNET_TIME_absolute_hton (expiration);
3417 GNUNET_assert (GNUNET_OK ==
3418 GNUNET_CRYPTO_ecc_sign (peer_key,
3419 &dns_advertisement.purpose,
3420 &dns_advertisement.signature));
3422 dht_put = GNUNET_DHT_put (dht,
3424 1 /* replication */,
3426 GNUNET_BLOCK_TYPE_DNS,
3427 sizeof (struct GNUNET_DNS_Advertisement),
3430 GNUNET_TIME_UNIT_FOREVER_REL,
3431 &dht_put_cont, NULL);
3436 * @brief Main function that will be run by the scheduler.
3438 * @param cls closure
3439 * @param args remaining command-line arguments
3440 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
3441 * @param cfg_ configuration
3444 run (void *cls, char *const *args GNUNET_UNUSED,
3445 const char *cfgfile GNUNET_UNUSED,
3446 const struct GNUNET_CONFIGURATION_Handle *cfg_)
3448 static struct GNUNET_MESH_MessageHandler handlers[] = {
3449 {&receive_icmp_service, GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_SERVICE, 0},
3450 {&receive_icmp_remote, GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_INTERNET, 0},
3451 {&receive_udp_service, GNUNET_MESSAGE_TYPE_VPN_UDP_TO_SERVICE, 0},
3452 {&receive_udp_remote, GNUNET_MESSAGE_TYPE_VPN_UDP_TO_INTERNET, 0},
3453 {&receive_tcp_service, GNUNET_MESSAGE_TYPE_VPN_TCP_TO_SERVICE_START, 0},
3454 {&receive_tcp_remote, GNUNET_MESSAGE_TYPE_VPN_TCP_TO_INTERNET_START, 0},
3455 {&receive_tcp_data, GNUNET_MESSAGE_TYPE_VPN_TCP_DATA_TO_EXIT, 0},
3456 {&receive_dns_request, GNUNET_MESSAGE_TYPE_VPN_DNS_TO_INTERNET, 0},
3460 static uint32_t apptypes[] = {
3461 GNUNET_APPLICATION_TYPE_END,
3462 GNUNET_APPLICATION_TYPE_END,
3463 GNUNET_APPLICATION_TYPE_END,
3464 GNUNET_APPLICATION_TYPE_END
3466 unsigned int app_idx;
3476 char *prefixed_regex;
3477 struct in_addr dns_exit4;
3478 struct in6_addr dns_exit6;
3482 ipv4_exit = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "EXIT_IPV4");
3483 ipv6_exit = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "EXIT_IPV6");
3484 ipv4_enabled = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "ENABLE_IPV4");
3485 ipv6_enabled = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "ENABLE_IPV6");
3486 if ( (ipv4_exit) || (ipv6_exit) )
3488 binary = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-exit");
3490 GNUNET_OS_check_helper_binary (binary, GNUNET_YES, "-d gnunet-vpn - - - 169.1.3.3.7 255.255.255.0")) //no nat, ipv4 only
3492 GNUNET_free (binary);
3493 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3494 _("`%s' must be installed SUID, refusing to run\n"),
3495 "gnunet-helper-exit");
3499 GNUNET_free (binary);
3501 stats = GNUNET_STATISTICS_create ("exit", cfg);
3503 if ( (ipv4_exit || ipv4_enabled) &&
3504 GNUNET_OK != GNUNET_NETWORK_test_pf (PF_INET))
3506 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3507 _("This system does not support IPv4, will disable IPv4 functions despite them being enabled in the configuration\n"));
3508 ipv4_exit = GNUNET_NO;
3509 ipv4_enabled = GNUNET_NO;
3511 if ( (ipv6_exit || ipv6_enabled) &&
3512 GNUNET_OK != GNUNET_NETWORK_test_pf (PF_INET6))
3514 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3515 _("This system does not support IPv6, will disable IPv6 functions despite them being enabled in the configuration\n"));
3516 ipv6_exit = GNUNET_NO;
3517 ipv6_enabled = GNUNET_NO;
3519 if (ipv4_exit && (! ipv4_enabled))
3521 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3522 _("Cannot enable IPv4 exit but disable IPv4 on TUN interface, will use ENABLE_IPv4=YES\n"));
3523 ipv4_enabled = GNUNET_YES;
3525 if (ipv6_exit && (! ipv6_enabled))
3527 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3528 _("Cannot enable IPv6 exit but disable IPv6 on TUN interface, will use ENABLE_IPv6=YES\n"));
3529 ipv6_enabled = GNUNET_YES;
3531 if (! (ipv4_enabled || ipv6_enabled))
3533 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
3534 _("No useful service enabled. Exiting.\n"));
3535 GNUNET_SCHEDULER_shutdown ();
3541 GNUNET_CONFIGURATION_get_value_yesno (cfg_, "exit", "ENABLE_DNS")) &&
3543 GNUNET_CONFIGURATION_get_value_string (cfg, "exit",
3546 ( (1 != inet_pton (AF_INET, dns_exit, &dns_exit4)) &&
3547 (1 != inet_pton (AF_INET6, dns_exit, &dns_exit6)) ) ) )
3549 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
3550 "dns", "DNS_RESOLVER",
3551 _("need a valid IPv4 or IPv6 address\n"));
3552 GNUNET_free_non_null (dns_exit);
3555 if (NULL != dns_exit)
3556 dnsstub = GNUNET_DNSSTUB_start (dns_exit);
3560 if (GNUNET_YES == ipv4_exit)
3562 // FIXME use regex to put info
3563 apptypes[app_idx] = GNUNET_APPLICATION_TYPE_IPV4_GATEWAY;
3566 if (GNUNET_YES == ipv6_exit)
3568 // FIXME use regex to put info
3569 apptypes[app_idx] = GNUNET_APPLICATION_TYPE_IPV6_GATEWAY;
3572 if (NULL != dns_exit)
3574 dht = GNUNET_DHT_connect (cfg, 1);
3575 peer_key = GNUNET_CRYPTO_ecc_key_create_from_configuration (cfg);
3576 GNUNET_CRYPTO_ecc_key_get_public_for_signature (peer_key,
3577 &dns_advertisement.peer.public_key);
3578 dns_advertisement.purpose.size = htonl (sizeof (struct GNUNET_DNS_Advertisement) -
3579 sizeof (struct GNUNET_CRYPTO_EccSignature));
3580 dns_advertisement.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_DNS_RECORD);
3581 GNUNET_CRYPTO_hash ("dns",
3584 dht_task = GNUNET_SCHEDULER_add_now (&do_dht_put,
3586 apptypes[app_idx] = GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER;
3590 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
3593 GNUNET_CONFIGURATION_get_value_number (cfg, "exit", "MAX_CONNECTIONS",
3595 max_connections = 1024;
3596 exit_argv[0] = GNUNET_strdup ("exit-gnunet");
3597 if (GNUNET_SYSERR ==
3598 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "TUN_IFNAME", &tun_ifname))
3600 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, "EXIT", "TUN_IFNAME");
3601 GNUNET_SCHEDULER_shutdown ();
3604 exit_argv[1] = tun_ifname;
3607 if (GNUNET_SYSERR ==
3608 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "EXIT_IFNAME", &exit_ifname))
3610 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, "EXIT", "EXIT_IFNAME");
3611 GNUNET_SCHEDULER_shutdown ();
3614 exit_argv[2] = exit_ifname;
3618 exit_argv[2] = GNUNET_strdup ("-");
3622 if (GNUNET_YES == ipv6_enabled)
3624 if ( (GNUNET_SYSERR ==
3625 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV6ADDR",
3627 (1 != inet_pton (AF_INET6, ipv6addr, &exit_ipv6addr))) )
3629 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, "EXIT", "IPV6ADDR");
3630 GNUNET_SCHEDULER_shutdown ();
3633 exit_argv[3] = ipv6addr;
3634 if (GNUNET_SYSERR ==
3635 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV6PREFIX",
3638 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, "EXIT", "IPV6PREFIX");
3639 GNUNET_SCHEDULER_shutdown ();
3642 exit_argv[4] = ipv6prefix_s;
3644 GNUNET_CONFIGURATION_get_value_number (cfg, "exit",
3647 (ipv6prefix >= 127) )
3649 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "EXIT", "IPV6PREFIX",
3650 _("Must be a number"));
3651 GNUNET_SCHEDULER_shutdown ();
3657 /* IPv6 explicitly disabled */
3658 exit_argv[3] = GNUNET_strdup ("-");
3659 exit_argv[4] = GNUNET_strdup ("-");
3661 if (GNUNET_YES == ipv4_enabled)
3663 if ( (GNUNET_SYSERR ==
3664 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV4ADDR",
3666 (1 != inet_pton (AF_INET, ipv4addr, &exit_ipv4addr))) )
3668 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, "EXIT", "IPV4ADDR");
3669 GNUNET_SCHEDULER_shutdown ();
3672 exit_argv[5] = ipv4addr;
3673 if ( (GNUNET_SYSERR ==
3674 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV4MASK",
3676 (1 != inet_pton (AF_INET, ipv4mask, &exit_ipv4mask))) )
3678 GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, "EXIT", "IPV4MASK");
3679 GNUNET_SCHEDULER_shutdown ();
3682 exit_argv[6] = ipv4mask;
3686 /* IPv4 explicitly disabled */
3687 exit_argv[5] = GNUNET_strdup ("-");
3688 exit_argv[6] = GNUNET_strdup ("-");
3690 exit_argv[7] = NULL;
3692 udp_services = GNUNET_CONTAINER_multihashmap_create (65536, GNUNET_NO);
3693 tcp_services = GNUNET_CONTAINER_multihashmap_create (65536, GNUNET_NO);
3694 GNUNET_CONFIGURATION_iterate_sections (cfg, &read_service_conf, NULL);
3696 connections_map = GNUNET_CONTAINER_multihashmap_create (65536, GNUNET_NO);
3697 connections_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
3699 = GNUNET_MESH_connect (cfg, NULL,
3701 &clean_tunnel, handlers,
3702 apptypes); // FIXME use ports
3703 if (NULL == mesh_handle)
3705 GNUNET_SCHEDULER_shutdown ();
3709 /* Mesh handle acquired, now announce regular expressions matching our exit */
3710 if ( (GNUNET_YES == ipv4_enabled) && (GNUNET_YES == ipv4_exit) )
3714 GNUNET_CONFIGURATION_get_value_string (cfg,
3716 "EXIT_RANGE_IPV4_REGEX",
3720 regex = GNUNET_TUN_ipv4policy2regex (policy);
3721 GNUNET_free_non_null (policy);
3724 (void) GNUNET_asprintf (&prefixed_regex, "%s%s%s",
3725 GNUNET_APPLICATION_TYPE_EXIT_REGEX_PREFIX,
3727 regex4 = GNUNET_REGEX_announce (cfg,
3729 REGEX_REFRESH_FREQUENCY,
3730 REGEX_MAX_PATH_LEN_IPV4);
3731 GNUNET_free (regex);
3732 GNUNET_free (prefixed_regex);
3736 if (GNUNET_YES == ipv6_enabled && GNUNET_YES == ipv6_exit)
3740 GNUNET_CONFIGURATION_get_value_string (cfg,
3742 "EXIT_RANGE_IPV6_REGEX",
3746 regex = GNUNET_TUN_ipv6policy2regex (policy);
3747 GNUNET_free_non_null (policy);
3750 (void) GNUNET_asprintf (&prefixed_regex, "%s%s%s",
3751 GNUNET_APPLICATION_TYPE_EXIT_REGEX_PREFIX,
3753 regex6 = GNUNET_REGEX_announce (cfg,
3755 REGEX_REFRESH_FREQUENCY,
3756 REGEX_MAX_PATH_LEN_IPV6);
3757 GNUNET_free (regex);
3758 GNUNET_free (prefixed_regex);
3761 if ((ipv4_exit) || (ipv6_exit))
3762 helper_handle = GNUNET_HELPER_start (GNUNET_NO,
3763 "gnunet-helper-exit",
3773 * @param argc number of arguments from the command line
3774 * @param argv command line arguments
3775 * @return 0 ok, 1 on error
3778 main (int argc, char *const *argv)
3780 static const struct GNUNET_GETOPT_CommandLineOption options[] = {
3781 GNUNET_GETOPT_OPTION_END
3784 if (GNUNET_OK != GNUNET_STRINGS_get_utf8_args (argc, argv, &argc, &argv))
3787 return (GNUNET_OK ==
3788 GNUNET_PROGRAM_run (argc, argv, "gnunet-daemon-exit",
3790 ("Daemon to run to provide an IP exit node for the VPN"),
3791 options, &run, NULL)) ? global_ret : 1;
3795 /* end of gnunet-daemon-exit.c */