2 This file is part of GNUnet.
3 (C) 2010 Christian Grothoff
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file vpn/gnunet-daemon-exit.c
24 * @author Philipp Toelke
27 #include <gnunet_common.h>
28 #include <gnunet_program_lib.h>
29 #include <gnunet_protocols.h>
30 #include <gnunet_applications.h>
31 #include <gnunet_mesh_service.h>
32 #include <gnunet_constants.h>
35 #include "gnunet-vpn-packet.h"
36 #include "gnunet-helper-vpn-api.h"
37 #include "gnunet-vpn-checksum.h"
39 GNUNET_SCHEDULER_TaskIdentifier shs_task;
42 * The handle to the configuration used throughout the process
44 static const struct GNUNET_CONFIGURATION_Handle *cfg;
47 * The handle to the helper
49 struct GNUNET_VPN_HELPER_Handle *helper_handle;
59 static struct GNUNET_MESH_Handle *mesh_handle;
62 * This hashmaps contains the mapping from peer, service-descriptor,
63 * source-port and destination-port to a struct redirect_state
65 static struct GNUNET_CONTAINER_MultiHashMap *udp_connections;
66 static struct GNUNET_CONTAINER_Heap *udp_connections_heap;
67 static struct GNUNET_CONTAINER_MultiHashMap *tcp_connections;
68 static struct GNUNET_CONTAINER_Heap *tcp_connections_heap;
71 * If there are at least this many udp-Connections, old ones will be removed
73 static long long unsigned int max_udp_connections = 200;
76 * If there are at least this many tcp-Connections, old ones will be removed
78 static long long unsigned int max_tcp_connections = 200;
83 unsigned char addr[16];
88 * This struct is saved into the services-hashmap
90 struct redirect_service
115 * The source-address of this connection. When a packet to this address is
116 * received, this tunnel is used to forward it. ipv4-addresses will be put
117 * here left-aligned */
120 * The source-port of this connection
126 * This struct is saved into {tcp,udp}_connections;
128 struct redirect_state
130 struct GNUNET_MESH_Tunnel *tunnel;
131 GNUNET_HashCode desc;
132 struct redirect_service *serv;
133 struct remote_addr remote;
135 struct GNUNET_CONTAINER_HeapNode *heap_node;
136 struct GNUNET_CONTAINER_MultiHashMap *hashmap;
137 GNUNET_HashCode hash;
140 { SERVICE, REMOTE } type;
143 * The source-address and -port of this connection
145 struct redirect_info redirect_info;
149 * This hashmaps saves interesting things about the configured services
151 static struct GNUNET_CONTAINER_MultiHashMap *udp_services;
152 static struct GNUNET_CONTAINER_MultiHashMap *tcp_services;
154 struct tunnel_notify_queue
156 struct tunnel_notify_queue *next;
157 struct tunnel_notify_queue *prev;
164 struct tunnel_notify_queue *head;
165 struct tunnel_notify_queue *tail;
166 struct GNUNET_MESH_TransmitHandle *th;
170 * Function that frees everything from a hashmap
173 free_iterate (void *cls GNUNET_UNUSED,
174 const GNUNET_HashCode * hash GNUNET_UNUSED, void *value)
181 * Function scheduled as very last function, cleans up after us
184 cleanup (void *cls GNUNET_UNUSED,
185 const struct GNUNET_SCHEDULER_TaskContext *tskctx)
187 GNUNET_assert (0 != (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
189 GNUNET_CONTAINER_multihashmap_iterate (udp_connections, free_iterate, NULL);
191 GNUNET_CONTAINER_multihashmap_iterate (tcp_connections, free_iterate, NULL);
193 if (mesh_handle != NULL)
195 GNUNET_MESH_disconnect (mesh_handle);
201 new_tunnel (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
202 const struct GNUNET_PeerIdentity *initiator GNUNET_UNUSED,
203 const struct GNUNET_ATS_Information *ats GNUNET_UNUSED)
205 struct tunnel_state *s = GNUNET_malloc (sizeof *s);
214 clean_tunnel (void *cls GNUNET_UNUSED, const struct GNUNET_MESH_Tunnel *tunnel,
217 GNUNET_free (tunnel_ctx);
221 collect_connections (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
223 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
227 struct GNUNET_CONTAINER_Heap *heap = cls;
229 struct redirect_state *state = GNUNET_CONTAINER_heap_remove_root (heap);
231 /* This is free()ed memory! */
232 state->heap_node = NULL;
234 /* FIXME! GNUNET_MESH_close_tunnel(state->tunnel); */
236 GNUNET_assert (GNUNET_OK ==
237 GNUNET_CONTAINER_multihashmap_remove (state->hashmap,
238 &state->hash, state));
244 hash_redirect_info (GNUNET_HashCode * hash, struct redirect_info *u_i,
248 /* the gnunet hashmap only uses the first sizeof(unsigned int) of the hash
250 * build the hash out of the last bytes of the address and the 2 bytes of
253 memcpy (hash, &u_i->pt, sizeof (u_i->pt));
254 memcpy (((unsigned char *) hash) + 2,
255 u_i->addr + (addrlen - (sizeof (unsigned int) - 2)),
256 (sizeof (unsigned int) - 2));
257 memset (((unsigned char *) hash) + sizeof (unsigned int), 0,
258 sizeof (GNUNET_HashCode) - sizeof (unsigned int));
262 * cls is the pointer to a GNUNET_MessageHeader that is
263 * followed by the service-descriptor and the udp-packet that should be sent;
266 send_udp_to_peer_notify_callback (void *cls, size_t size, void *buf)
268 struct GNUNET_MESH_Tunnel **tunnel = cls;
270 GNUNET_MESH_tunnel_set_data (*tunnel, NULL);
271 struct GNUNET_MessageHeader *hdr =
272 (struct GNUNET_MessageHeader *) (tunnel + 1);
273 GNUNET_assert (size >= ntohs (hdr->size));
274 memcpy (buf, hdr, ntohs (hdr->size));
275 size = ntohs (hdr->size);
277 struct tunnel_state *s = GNUNET_MESH_tunnel_get_data (*tunnel);
281 struct tunnel_notify_queue *element = s->head;
283 GNUNET_CONTAINER_DLL_remove (s->head, s->tail, element);
286 GNUNET_MESH_notify_transmit_ready (*tunnel, GNUNET_NO, 42,
287 GNUNET_TIME_relative_divide
288 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
289 (const struct GNUNET_PeerIdentity *)
291 send_udp_to_peer_notify_callback,
294 /* save the handle */
295 GNUNET_free (element);
304 * @brief Handles an UDP-Packet received from the helper.
306 * @param udp A pointer to the Packet
307 * @param dadr The IP-Destination-address
308 * @param addrlen The length of the address
311 udp_from_helper (struct udp_pkt *udp, unsigned char *dadr, size_t addrlen)
313 struct redirect_info u_i;
314 struct GNUNET_MESH_Tunnel *tunnel;
316 struct GNUNET_MessageHeader *msg;
318 memset (&u_i, 0, sizeof (struct redirect_info));
320 memcpy (&u_i.addr, dadr, addrlen);
324 /* get tunnel and service-descriptor from this */
325 GNUNET_HashCode hash;
327 hash_redirect_info (&hash, &u_i, addrlen);
329 struct redirect_state *state =
330 GNUNET_CONTAINER_multihashmap_get (udp_connections, &hash);
332 /* Mark this connection as freshly used */
333 GNUNET_CONTAINER_heap_update_cost (udp_connections_heap, state->heap_node,
334 GNUNET_TIME_absolute_get ().abs_value);
336 tunnel = state->tunnel;
338 if (state->type == SERVICE)
340 /* check if spt == serv.remote if yes: set spt = serv.myport ("nat") */
341 if (ntohs (udp->spt) == state->serv->remote_port)
343 udp->spt = htons (state->serv->my_port);
347 /* otherwise the answer came from a different port (tftp does this)
348 * add this new port to the list of all services, so that the packets
349 * coming back from the client to this new port will be routed correctly
351 struct redirect_service *serv =
352 GNUNET_malloc (sizeof (struct redirect_service));
353 memcpy (serv, state->serv, sizeof (struct redirect_service));
354 serv->my_port = ntohs (udp->spt);
355 serv->remote_port = ntohs (udp->spt);
356 uint16_t *desc = alloca (sizeof (GNUNET_HashCode) + 2);
358 memcpy ((GNUNET_HashCode *) (desc + 1), &state->desc,
359 sizeof (GNUNET_HashCode));
360 *desc = ntohs (udp->spt);
361 GNUNET_assert (GNUNET_OK ==
362 GNUNET_CONTAINER_multihashmap_put (udp_services,
365 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
371 /* send udp-packet back */
373 sizeof (struct GNUNET_MessageHeader) + sizeof (GNUNET_HashCode) +
375 struct GNUNET_MESH_Tunnel **ctunnel =
376 GNUNET_malloc (sizeof (struct GNUNET_MESH_TUNNEL *) + len);
378 msg = (struct GNUNET_MessageHeader *) (ctunnel + 1);
379 msg->size = htons (len);
381 htons (state->type ==
382 SERVICE ? GNUNET_MESSAGE_TYPE_VPN_SERVICE_UDP_BACK :
383 GNUNET_MESSAGE_TYPE_VPN_REMOTE_UDP_BACK);
384 GNUNET_HashCode *desc = (GNUNET_HashCode *) (msg + 1);
386 if (state->type == SERVICE)
387 memcpy (desc, &state->desc, sizeof (GNUNET_HashCode));
389 memcpy (desc, &state->remote, sizeof (struct remote_addr));
390 void *_udp = desc + 1;
392 memcpy (_udp, udp, ntohs (udp->len));
394 struct tunnel_state *s = GNUNET_MESH_tunnel_get_data (tunnel);
398 /* No notify is pending */
400 GNUNET_MESH_notify_transmit_ready (tunnel, GNUNET_NO, 42,
401 GNUNET_TIME_relative_divide
402 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
403 (const struct GNUNET_PeerIdentity *)
405 send_udp_to_peer_notify_callback,
410 struct tunnel_notify_queue *element =
411 GNUNET_malloc (sizeof (struct tunnel_notify_queue));
412 element->cls = ctunnel;
415 GNUNET_CONTAINER_DLL_insert_tail (s->head, s->tail, element);
420 * @brief Handles a TCP-Packet received from the helper.
422 * @param tcp A pointer to the Packet
423 * @param dadr The IP-Destination-address
424 * @param addrlen The length of the address
425 * @param pktlen the length of the packet, including its header
428 tcp_from_helper (struct tcp_pkt *tcp, unsigned char *dadr, size_t addrlen,
431 struct redirect_info u_i;
432 struct GNUNET_MESH_Tunnel *tunnel;
434 struct GNUNET_MessageHeader *msg;
436 memset (&u_i, 0, sizeof (struct redirect_info));
438 memcpy (&u_i.addr, dadr, addrlen);
441 /* get tunnel and service-descriptor from this */
442 GNUNET_HashCode hash;
444 hash_redirect_info (&hash, &u_i, addrlen);
446 struct redirect_state *state =
447 GNUNET_CONTAINER_multihashmap_get (tcp_connections, &hash);
451 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
452 "No mapping for this connection; hash is %x\n",
453 *((uint32_t *) & hash));
457 /* Mark this connection as freshly used */
458 GNUNET_CONTAINER_heap_update_cost (tcp_connections_heap, state->heap_node,
459 GNUNET_TIME_absolute_get ().abs_value);
461 tunnel = state->tunnel;
463 if (state->type == SERVICE)
465 /* check if spt == serv.remote if yes: set spt = serv.myport ("nat") */
466 if (ntohs (tcp->spt) == state->serv->remote_port)
468 tcp->spt = htons (state->serv->my_port);
472 // This is an illegal packet.
477 /* send tcp-packet back */
479 sizeof (struct GNUNET_MessageHeader) + sizeof (GNUNET_HashCode) + pktlen;
480 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "len: %d\n", pktlen);
481 struct GNUNET_MESH_Tunnel **ctunnel =
482 GNUNET_malloc (sizeof (struct GNUNET_MESH_TUNNEL *) + len);
484 msg = (struct GNUNET_MessageHeader *) (ctunnel + 1);
485 msg->size = htons (len);
487 htons (state->type ==
488 SERVICE ? GNUNET_MESSAGE_TYPE_VPN_SERVICE_TCP_BACK :
489 GNUNET_MESSAGE_TYPE_VPN_REMOTE_TCP_BACK);
490 GNUNET_HashCode *desc = (GNUNET_HashCode *) (msg + 1);
492 if (state->type == SERVICE)
493 memcpy (desc, &state->desc, sizeof (GNUNET_HashCode));
495 memcpy (desc, &state->remote, sizeof (struct remote_addr));
496 void *_tcp = desc + 1;
498 memcpy (_tcp, tcp, pktlen);
500 struct tunnel_state *s = GNUNET_MESH_tunnel_get_data (tunnel);
504 /* No notify is pending */
506 GNUNET_MESH_notify_transmit_ready (tunnel, GNUNET_NO, 42,
507 GNUNET_TIME_relative_divide
508 (GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
509 (const struct GNUNET_PeerIdentity *)
511 send_udp_to_peer_notify_callback,
516 struct tunnel_notify_queue *element =
517 GNUNET_malloc (sizeof (struct tunnel_notify_queue));
518 element->cls = ctunnel;
521 GNUNET_CONTAINER_DLL_insert_tail (s->head, s->tail, element);
527 * Receive packets from the helper-process
530 message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED,
531 const struct GNUNET_MessageHeader *message)
533 GNUNET_assert (ntohs (message->type) == GNUNET_MESSAGE_TYPE_VPN_HELPER);
535 struct tun_pkt *pkt_tun = (struct tun_pkt *) message;
537 /* ethertype is ipv6 */
538 if (ntohs (pkt_tun->tun.type) == 0x86dd)
540 struct ip6_pkt *pkt6 = (struct ip6_pkt *) pkt_tun;
542 if (IPPROTO_UDP == pkt6->ip6_hdr.nxthdr)
543 udp_from_helper (&((struct ip6_udp *) pkt6)->udp_hdr,
544 (unsigned char *) &pkt6->ip6_hdr.dadr, 16);
545 else if (IPPROTO_TCP == pkt6->ip6_hdr.nxthdr)
546 tcp_from_helper (&((struct ip6_tcp *) pkt6)->tcp_hdr,
547 (unsigned char *) &pkt6->ip6_hdr.dadr, 16,
548 ntohs (pkt6->ip6_hdr.paylgth));
550 else if (ntohs (pkt_tun->tun.type) == 0x0800)
552 struct ip_pkt *pkt4 = (struct ip_pkt *) pkt_tun;
553 uint32_t tmp = pkt4->ip_hdr.dadr;
555 if (IPPROTO_UDP == pkt4->ip_hdr.proto)
556 udp_from_helper (&((struct ip_udp *) pkt4)->udp_hdr,
557 (unsigned char *) &tmp, 4);
558 else if (IPPROTO_TCP == pkt4->ip_hdr.proto)
560 size_t pktlen = ntohs (pkt4->ip_hdr.tot_lngth);
562 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "tot: %d\n", pktlen);
563 pktlen -= 4 * pkt4->ip_hdr.hdr_lngth;
564 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "-hdr: %d\n", pktlen);
565 tcp_from_helper (&((struct ip_tcp *) pkt4)->tcp_hdr,
566 (unsigned char *) &tmp, 4, pktlen);
576 * Reads the configuration servicecfg and populates udp_services
579 * @param section name of section in config, equal to hostname
582 read_service_conf (void *cls GNUNET_UNUSED, const char *section)
584 if ((strlen (section) < 8) ||
585 (0 != strcmp (".gnunet.", section + (strlen (section) - 8))))
588 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Parsing dns-name %d %s %s\n",
589 strlen (section), section, section + (strlen (section) - 8));
595 uint16_t *desc = alloca (sizeof (GNUNET_HashCode) + 2);
597 GNUNET_CRYPTO_hash (section, strlen (section) + 1,
598 (GNUNET_HashCode *) (desc + 1));
609 GNUNET_CONFIGURATION_get_value_string (cfg, section, "UDP_REDIRECTS",
612 else if (proto == TCP &&
614 GNUNET_CONFIGURATION_get_value_string (cfg, section,
615 "TCP_REDIRECTS", &cpy)))
618 for (redirect = strtok (cpy, " "); redirect != NULL;
619 redirect = strtok (NULL, " "))
621 if (NULL == (hostname = strstr (redirect, ":")))
623 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
624 "Warning: option %s is not formatted correctly!\n",
630 if (NULL == (hostport = strstr (hostname, ":")))
632 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
633 "Warning: option %s is not formatted correctly!\n",
640 int local_port = atoi (redirect);
642 if (!((local_port > 0) && (local_port < 65536)))
643 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
644 "Warning: %s is not a correct port.", redirect);
648 struct redirect_service *serv =
649 GNUNET_malloc (sizeof (struct redirect_service));
650 serv->my_port = local_port;
652 if (0 == strcmp ("localhost4", hostname))
658 GNUNET_assert (GNUNET_OK ==
659 GNUNET_CONFIGURATION_get_value_string (cfg, "exit",
662 GNUNET_assert (1 == inet_pton (AF_INET, ip4addr, serv->v4.ip4address));
663 GNUNET_free (ip4addr);
665 else if (0 == strcmp ("localhost6", hostname))
671 GNUNET_assert (GNUNET_OK ==
672 GNUNET_CONFIGURATION_get_value_string (cfg, "exit",
675 GNUNET_assert (1 == inet_pton (AF_INET6, ip6addr, serv->v6.ip6address));
676 GNUNET_free (ip6addr);
680 struct addrinfo *res;
682 int ret = getaddrinfo (hostname, NULL, NULL, &res);
686 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No addresses found for %s!\n",
694 struct addrinfo *c = res;
698 if (c->ai_family == AF_INET)
701 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
702 "Found %s as address for %s\n",
703 inet_ntop (c->ai_family,
704 &((struct sockaddr_in *) (c->
706 (char *) &buf, 256), hostname);
707 memcpy (serv->v4.ip4address,
708 &((struct sockaddr_in *) (c->ai_addr))->sin_addr, 4);
710 else if (c->ai_family == AF_INET6)
713 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
714 "Found %s as address for %s\n",
715 inet_ntop (c->ai_family,
716 &((struct sockaddr_in6 *) (c->
717 ai_addr))->sin6_addr,
718 (char *) &buf, 256), hostname);
719 memcpy (serv->v6.ip6address,
720 &((struct sockaddr_in6 *) (c->ai_addr))->sin6_addr, 16);
732 serv->remote_port = atoi (hostport);
734 GNUNET_assert (GNUNET_OK ==
735 GNUNET_CONTAINER_multihashmap_put (udp_services,
738 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
740 GNUNET_assert (GNUNET_OK ==
741 GNUNET_CONTAINER_multihashmap_put (tcp_services,
744 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
749 proto = (proto == UDP) ? TCP : UDP;
751 while (proto != UDP);
755 * Start the helper-process
757 * If cls != NULL it is assumed that this function is called as a result of a dying
758 * helper. cls is then taken as handle to the old helper and is cleaned up.
761 start_helper_and_schedule (void *cls,
762 const struct GNUNET_SCHEDULER_TaskContext *tc)
764 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
768 cleanup_helper (cls);
778 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IFNAME", &ifname))
780 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
781 "No entry 'IFNAME' in configuration!\n");
786 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV6ADDR",
789 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
790 "No entry 'IPV6ADDR' in configuration!\n");
795 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV6PREFIX",
798 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
799 "No entry 'IPV6PREFIX' in configuration!\n");
804 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV4ADDR",
807 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
808 "No entry 'IPV4ADDR' in configuration!\n");
813 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV4MASK",
816 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
817 "No entry 'IPV4MASK' in configuration!\n");
822 * Messages get passed to the function message_token
823 * When the helper dies, this function will be called again with the
824 * helper_handle as cls.
827 start_helper (ifname, ipv6addr, ipv6prefix, ipv4addr, ipv4mask,
828 "exit-gnunet", start_helper_and_schedule, message_token,
831 GNUNET_free (ipv6addr);
832 GNUNET_free (ipv6prefix);
833 GNUNET_free (ipv4addr);
834 GNUNET_free (ipv4mask);
835 GNUNET_free (ifname);
839 prepare_ipv4_packet (size_t len, uint16_t pktlen, void *payload,
840 uint16_t protocol, void *ipaddress, void *tunnel,
841 struct redirect_state *state, struct ip_pkt *pkt4)
845 pkt4->shdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
846 pkt4->shdr.size = htons (len);
848 pkt4->tun.type = htons (0x0800);
850 memcpy (&pkt4->data, payload, pktlen);
852 pkt4->ip_hdr.version = 4;
853 pkt4->ip_hdr.hdr_lngth = 5;
854 pkt4->ip_hdr.diff_serv = 0;
855 pkt4->ip_hdr.tot_lngth = htons (20 + pktlen);
856 pkt4->ip_hdr.ident = 0;
857 pkt4->ip_hdr.flags = 0;
858 pkt4->ip_hdr.frag_off = 0;
859 pkt4->ip_hdr.ttl = 255;
860 pkt4->ip_hdr.proto = protocol;
861 pkt4->ip_hdr.chks = 0; /* Will be calculated later */
863 memcpy (&tmp, ipaddress, 4);
864 pkt4->ip_hdr.dadr = tmp;
866 /* Generate a new src-address */
870 GNUNET_assert (GNUNET_OK ==
871 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV4ADDR",
873 GNUNET_assert (GNUNET_OK ==
874 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV4MASK",
876 inet_pton (AF_INET, ipv4addr, &tmp);
877 inet_pton (AF_INET, ipv4mask, &tmp2);
878 GNUNET_free (ipv4addr);
879 GNUNET_free (ipv4mask);
881 /* This should be a noop */
884 tmp |= ntohl (*((uint32_t *) tunnel)) & (~tmp2);
886 pkt4->ip_hdr.sadr = tmp;
888 memcpy (&state->redirect_info.addr, &tmp, 4);
889 if (IPPROTO_UDP == protocol)
891 struct ip_udp *pkt4_udp = (struct ip_udp *) pkt4;
893 state->redirect_info.pt = pkt4_udp->udp_hdr.spt;
895 pkt4_udp->udp_hdr.crc = 0; /* Optional for IPv4 */
897 else if (IPPROTO_TCP == protocol)
899 struct ip_tcp *pkt4_tcp = (struct ip_tcp *) pkt4;
901 state->redirect_info.pt = pkt4_tcp->tcp_hdr.spt;
903 pkt4_tcp->tcp_hdr.crc = 0;
906 tmp = pkt4->ip_hdr.sadr;
907 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
908 tmp = pkt4->ip_hdr.dadr;
909 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
911 tmp = (protocol << 16) | (0xffff & pktlen);
913 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "line: %08x, %x \n", tmp,
918 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
921 calculate_checksum_update (sum, (uint16_t *) & pkt4_tcp->tcp_hdr,
923 pkt4_tcp->tcp_hdr.crc = calculate_checksum_end (sum);
927 calculate_ip_checksum ((uint16_t *) & pkt4->ip_hdr, 5 * 4);
931 prepare_ipv6_packet (size_t len, uint16_t pktlen, void *payload,
932 uint16_t protocol, void *ipaddress, void *tunnel,
933 struct redirect_state *state, struct ip6_pkt *pkt6)
937 pkt6->shdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
938 pkt6->shdr.size = htons (len);
941 pkt6->tun.type = htons (0x86dd);
943 memcpy (&pkt6->data, payload, pktlen);
945 pkt6->ip6_hdr.version = 6;
946 pkt6->ip6_hdr.nxthdr = protocol;
947 pkt6->ip6_hdr.paylgth = htons (pktlen);
948 pkt6->ip6_hdr.hoplmt = 64;
950 memcpy (pkt6->ip6_hdr.dadr, ipaddress, 16);
952 /* Generate a new src-address
953 * This takes as much from the address of the tunnel as fits into
956 unsigned long long ipv6prefix;
958 GNUNET_assert (GNUNET_OK ==
959 GNUNET_CONFIGURATION_get_value_string (cfg, "exit", "IPV6ADDR",
961 GNUNET_assert (GNUNET_OK ==
962 GNUNET_CONFIGURATION_get_value_number (cfg, "exit",
965 GNUNET_assert (ipv6prefix < 127);
966 ipv6prefix = (ipv6prefix + 7) / 8;
968 inet_pton (AF_INET6, ipv6addr, &pkt6->ip6_hdr.sadr);
969 GNUNET_free (ipv6addr);
971 if (ipv6prefix < (16 - sizeof (void *)))
972 ipv6prefix = 16 - sizeof (void *);
974 unsigned int offset = ipv6prefix - (16 - sizeof (void *));
976 memcpy ((((char *) &pkt6->ip6_hdr.sadr)) + ipv6prefix,
977 ((char *) &tunnel) + offset, 16 - ipv6prefix);
979 /* copy the needed information into the state */
980 memcpy (&state->redirect_info.addr, &pkt6->ip6_hdr.sadr, 16);
982 if (IPPROTO_UDP == protocol)
984 struct ip6_udp *pkt6_udp = (struct ip6_udp *) pkt6;
986 state->redirect_info.pt = pkt6_udp->udp_hdr.spt;
988 pkt6_udp->udp_hdr.crc = 0;
992 calculate_checksum_update (sum, (uint16_t *) & pkt6_udp->ip6_hdr.sadr,
995 calculate_checksum_update (sum, (uint16_t *) & pkt6_udp->ip6_hdr.dadr,
997 tmp = (htons (pktlen) & 0xffff);
998 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
999 tmp = htons (((pkt6_udp->ip6_hdr.nxthdr & 0x00ff)));
1000 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
1003 calculate_checksum_update (sum, (uint16_t *) & pkt6_udp->udp_hdr,
1004 ntohs (pkt6_udp->udp_hdr.len));
1005 pkt6_udp->udp_hdr.crc = calculate_checksum_end (sum);
1007 else if (IPPROTO_TCP == protocol)
1009 struct ip6_tcp *pkt6_tcp = (struct ip6_tcp *) pkt6;
1011 state->redirect_info.pt = pkt6_tcp->tcp_hdr.spt;
1013 pkt6_tcp->tcp_hdr.crc = 0;
1017 calculate_checksum_update (sum, (uint16_t *) & pkt6->ip6_hdr.sadr, 16);
1019 calculate_checksum_update (sum, (uint16_t *) & pkt6->ip6_hdr.dadr, 16);
1020 tmp = htonl (pktlen);
1021 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
1022 tmp = htonl (((pkt6->ip6_hdr.nxthdr & 0x000000ff)));
1023 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
1026 calculate_checksum_update (sum, (uint16_t *) & pkt6_tcp->tcp_hdr,
1027 ntohs (pkt6->ip6_hdr.paylgth));
1028 pkt6_tcp->tcp_hdr.crc = calculate_checksum_end (sum);
1033 * The messages are one GNUNET_HashCode for the service followed by a struct tcp_pkt
1036 receive_tcp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1037 void **tunnel_ctx GNUNET_UNUSED,
1038 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1039 const struct GNUNET_MessageHeader *message,
1040 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1042 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received TCP-Packet\n");
1043 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
1044 struct tcp_pkt *pkt = (struct tcp_pkt *) (desc + 1);
1046 ntohs (message->size) - sizeof (struct GNUNET_MessageHeader) -
1047 sizeof (GNUNET_HashCode);
1049 /** Get the configuration from the services-hashmap.
1051 * Which service is needed only depends on the service-descriptor and the
1054 uint16_t *tcp_desc = alloca (sizeof (GNUNET_HashCode) + 2);
1056 memcpy (tcp_desc + 1, desc, sizeof (GNUNET_HashCode));
1057 *tcp_desc = ntohs (pkt->dpt);
1058 struct redirect_service *serv =
1059 GNUNET_CONTAINER_multihashmap_get (tcp_services,
1060 (GNUNET_HashCode *) tcp_desc);
1064 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "No service found for TCP dpt %d!\n",
1069 pkt->dpt = htons (serv->remote_port);
1072 * At this point it would be possible to check against some kind of ACL.
1078 /* Prepare the state.
1079 * This will be saved in the hashmap, so that the receiving procedure knows
1080 * through which tunnel this connection has to be routed.
1082 struct redirect_state *state = GNUNET_malloc (sizeof (struct redirect_state));
1084 state->tunnel = tunnel;
1086 state->type = SERVICE;
1087 state->hashmap = tcp_connections;
1088 memcpy (&state->desc, desc, sizeof (GNUNET_HashCode));
1091 sizeof (struct GNUNET_MessageHeader) + sizeof (struct pkt_tun) +
1092 sizeof (struct ip6_hdr) + pkt_len;
1095 memset (buf, 0, len);
1097 switch (serv->version)
1100 prepare_ipv4_packet (len, pkt_len, pkt, IPPROTO_TCP, &serv->v4.ip4address,
1101 tunnel, state, (struct ip_pkt *) buf);
1104 prepare_ipv6_packet (len, pkt_len, pkt, IPPROTO_TCP, &serv->v6.ip6address,
1105 tunnel, state, (struct ip6_pkt *) buf);
1113 hash_redirect_info (&state->hash, &state->redirect_info,
1114 serv->version == 4 ? 4 : 16);
1117 GNUNET_CONTAINER_multihashmap_contains (tcp_connections, &state->hash))
1119 GNUNET_CONTAINER_multihashmap_put (tcp_connections, &state->hash, state,
1120 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1123 GNUNET_CONTAINER_heap_insert (tcp_connections_heap, state,
1124 GNUNET_TIME_absolute_get ().abs_value);
1126 if (GNUNET_CONTAINER_heap_get_size (tcp_connections_heap) >
1127 max_tcp_connections)
1128 GNUNET_SCHEDULER_add_now (collect_connections, tcp_connections_heap);
1131 GNUNET_free (state);
1133 (void) GNUNET_DISK_file_write (helper_handle->fh_to_helper, buf, len);
1138 receive_tcp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1139 void **tunnel_ctx GNUNET_UNUSED,
1140 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1141 const struct GNUNET_MessageHeader *message,
1142 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1144 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
1145 struct tcp_pkt *pkt = (struct tcp_pkt *) (desc + 1);
1146 struct remote_addr *s = (struct remote_addr *) desc;
1150 ntohs (message->size) - sizeof (struct GNUNET_MessageHeader) -
1151 sizeof (GNUNET_HashCode);
1153 struct redirect_state *state = GNUNET_malloc (sizeof (struct redirect_state));
1155 state->tunnel = tunnel;
1156 state->type = REMOTE;
1157 state->hashmap = tcp_connections;
1158 memcpy (&state->remote, s, sizeof (struct remote_addr));
1161 sizeof (struct GNUNET_MessageHeader) + sizeof (struct pkt_tun) +
1162 sizeof (struct ip6_hdr) + pkt_len;
1165 memset (buf, 0, len);
1170 prepare_ipv4_packet (len, pkt_len, pkt, IPPROTO_TCP, &s->addr, tunnel,
1171 state, (struct ip_pkt *) buf);
1174 prepare_ipv6_packet (len, pkt_len, pkt, IPPROTO_TCP, &s->addr, tunnel,
1175 state, (struct ip6_pkt *) buf);
1178 GNUNET_free (state);
1179 return GNUNET_SYSERR;
1182 hash_redirect_info (&state->hash, &state->redirect_info, s->addrlen);
1184 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Packet from remote; hash is %x\n",
1185 *((uint32_t *) & state->hash));
1188 GNUNET_CONTAINER_multihashmap_contains (tcp_connections, &state->hash))
1190 GNUNET_CONTAINER_multihashmap_put (tcp_connections, &state->hash, state,
1191 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1194 GNUNET_CONTAINER_heap_insert (tcp_connections_heap, state,
1195 GNUNET_TIME_absolute_get ().abs_value);
1197 if (GNUNET_CONTAINER_heap_get_size (tcp_connections_heap) >
1198 max_tcp_connections)
1199 GNUNET_SCHEDULER_add_now (collect_connections, tcp_connections_heap);
1202 GNUNET_free (state);
1204 (void) GNUNET_DISK_file_write (helper_handle->fh_to_helper, buf, len);
1210 receive_udp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1211 void **tunnel_ctx GNUNET_UNUSED,
1212 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1213 const struct GNUNET_MessageHeader *message,
1214 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1216 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
1217 struct udp_pkt *pkt = (struct udp_pkt *) (desc + 1);
1218 struct remote_addr *s = (struct remote_addr *) desc;
1222 GNUNET_assert (ntohs (pkt->len) ==
1223 ntohs (message->size) - sizeof (struct GNUNET_MessageHeader) -
1224 sizeof (GNUNET_HashCode));
1226 /* Prepare the state.
1227 * This will be saved in the hashmap, so that the receiving procedure knows
1228 * through which tunnel this connection has to be routed.
1230 struct redirect_state *state = GNUNET_malloc (sizeof (struct redirect_state));
1232 state->tunnel = tunnel;
1233 state->hashmap = udp_connections;
1234 state->type = REMOTE;
1235 memcpy (&state->remote, s, sizeof (struct remote_addr));
1238 sizeof (struct GNUNET_MessageHeader) + sizeof (struct pkt_tun) +
1239 sizeof (struct ip6_hdr) + ntohs (pkt->len);
1242 memset (buf, 0, len);
1247 prepare_ipv4_packet (len, ntohs (pkt->len), pkt, IPPROTO_UDP, &s->addr,
1248 tunnel, state, (struct ip_pkt *) buf);
1251 prepare_ipv6_packet (len, ntohs (pkt->len), pkt, IPPROTO_UDP, &s->addr,
1252 tunnel, state, (struct ip6_pkt *) buf);
1259 hash_redirect_info (&state->hash, &state->redirect_info, s->addrlen);
1262 GNUNET_CONTAINER_multihashmap_contains (udp_connections, &state->hash))
1264 GNUNET_CONTAINER_multihashmap_put (udp_connections, &state->hash, state,
1265 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1268 GNUNET_CONTAINER_heap_insert (udp_connections_heap, state,
1269 GNUNET_TIME_absolute_get ().abs_value);
1271 if (GNUNET_CONTAINER_heap_get_size (udp_connections_heap) >
1272 max_udp_connections)
1273 GNUNET_SCHEDULER_add_now (collect_connections, udp_connections_heap);
1276 GNUNET_free (state);
1278 (void) GNUNET_DISK_file_write (helper_handle->fh_to_helper, buf, len);
1283 * The messages are one GNUNET_HashCode for the service, followed by a struct udp_pkt
1286 receive_udp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel,
1288 const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED,
1289 const struct GNUNET_MessageHeader *message,
1290 const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
1292 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
1293 struct udp_pkt *pkt = (struct udp_pkt *) (desc + 1);
1295 GNUNET_assert (ntohs (pkt->len) ==
1296 ntohs (message->size) - sizeof (struct GNUNET_MessageHeader) -
1297 sizeof (GNUNET_HashCode));
1299 /* Get the configuration from the hashmap */
1300 uint16_t *udp_desc = alloca (sizeof (GNUNET_HashCode) + 2);
1302 memcpy (udp_desc + 1, desc, sizeof (GNUNET_HashCode));
1303 *udp_desc = ntohs (pkt->dpt);
1304 struct redirect_service *serv =
1305 GNUNET_CONTAINER_multihashmap_get (udp_services,
1306 (GNUNET_HashCode *) udp_desc);
1310 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "No service found for UDP dpt %d!\n",
1315 pkt->dpt = htons (serv->remote_port);
1318 * At this point it would be possible to check against some kind of ACL.
1324 /* Prepare the state.
1325 * This will be saved in the hashmap, so that the receiving procedure knows
1326 * through which tunnel this connection has to be routed.
1328 struct redirect_state *state = GNUNET_malloc (sizeof (struct redirect_state));
1330 state->tunnel = tunnel;
1332 state->type = SERVICE;
1333 state->hashmap = udp_connections;
1334 memcpy (&state->desc, desc, sizeof (GNUNET_HashCode));
1337 sizeof (struct GNUNET_MessageHeader) + sizeof (struct pkt_tun) +
1338 sizeof (struct ip6_hdr) + ntohs (pkt->len);
1341 memset (buf, 0, len);
1343 switch (serv->version)
1346 prepare_ipv4_packet (len, ntohs (pkt->len), pkt, IPPROTO_UDP,
1347 &serv->v4.ip4address, tunnel, state,
1348 (struct ip_pkt *) buf);
1351 prepare_ipv6_packet (len, ntohs (pkt->len), pkt, IPPROTO_UDP,
1352 &serv->v6.ip6address, tunnel, state,
1353 (struct ip6_pkt *) buf);
1361 hash_redirect_info (&state->hash, &state->redirect_info,
1362 serv->version == 4 ? 4 : 16);
1365 GNUNET_CONTAINER_multihashmap_contains (udp_connections, &state->hash))
1367 GNUNET_CONTAINER_multihashmap_put (udp_connections, &state->hash, state,
1368 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1371 GNUNET_CONTAINER_heap_insert (udp_connections_heap, state,
1372 GNUNET_TIME_absolute_get ().abs_value);
1374 if (GNUNET_CONTAINER_heap_get_size (udp_connections_heap) >
1375 max_udp_connections)
1376 GNUNET_SCHEDULER_add_now (collect_connections, udp_connections_heap);
1379 GNUNET_free (state);
1381 (void) GNUNET_DISK_file_write (helper_handle->fh_to_helper, buf, len);
1389 int handler_idx, app_idx;
1391 udp = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "ENABLE_UDP");
1392 tcp = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "ENABLE_TCP");
1394 static struct GNUNET_MESH_MessageHandler handlers[] = {
1395 {receive_udp_service, GNUNET_MESSAGE_TYPE_VPN_SERVICE_UDP, 0},
1396 {receive_tcp_service, GNUNET_MESSAGE_TYPE_VPN_SERVICE_TCP, 0},
1402 static GNUNET_MESH_ApplicationType apptypes[] = {
1403 GNUNET_APPLICATION_TYPE_END,
1404 GNUNET_APPLICATION_TYPE_END,
1405 GNUNET_APPLICATION_TYPE_END
1411 if (GNUNET_YES == udp)
1413 handlers[handler_idx].callback = receive_udp_remote;
1414 handlers[handler_idx].expected_size = 0;
1415 handlers[handler_idx].type = GNUNET_MESSAGE_TYPE_VPN_REMOTE_UDP;
1416 apptypes[app_idx] = GNUNET_APPLICATION_TYPE_INTERNET_UDP_GATEWAY;
1421 if (GNUNET_YES == tcp)
1423 handlers[handler_idx].callback = receive_tcp_remote;
1424 handlers[handler_idx].expected_size = 0;
1425 handlers[handler_idx].type = GNUNET_MESSAGE_TYPE_VPN_REMOTE_TCP;
1426 apptypes[app_idx] = GNUNET_APPLICATION_TYPE_INTERNET_TCP_GATEWAY;
1432 GNUNET_MESH_connect (cfg, 42, NULL, new_tunnel, clean_tunnel, handlers,
1438 * @brief Main function that will be run by the scheduler.
1440 * @param cls closure
1441 * @param args remaining command-line arguments
1442 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
1443 * @param cfg_ configuration
1446 run (void *cls, char *const *args GNUNET_UNUSED,
1447 const char *cfgfile GNUNET_UNUSED,
1448 const struct GNUNET_CONFIGURATION_Handle *cfg_)
1454 udp_connections = GNUNET_CONTAINER_multihashmap_create (65536);
1455 udp_connections_heap =
1456 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1457 tcp_connections = GNUNET_CONTAINER_multihashmap_create (65536);
1458 tcp_connections_heap =
1459 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1460 udp_services = GNUNET_CONTAINER_multihashmap_create (65536);
1461 tcp_services = GNUNET_CONTAINER_multihashmap_create (65536);
1464 GNUNET_CONFIGURATION_get_value_number (cfg, "exit", "MAX_UDP_CONNECTIONS",
1465 &max_udp_connections))
1466 max_udp_connections = 1024;
1468 GNUNET_CONFIGURATION_get_value_number (cfg, "exit", "MAX_TCP_CONNECTIONS",
1469 &max_tcp_connections))
1470 max_tcp_connections = 256;
1471 GNUNET_CONFIGURATION_iterate_sections (cfg, read_service_conf, NULL);
1472 GNUNET_SCHEDULER_add_now (start_helper_and_schedule, NULL);
1473 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
1480 * @param argc number of arguments from the command line
1481 * @param argv command line arguments
1482 * @return 0 ok, 1 on error
1485 main (int argc, char *const *argv)
1487 static const struct GNUNET_GETOPT_CommandLineOption options[] = {
1488 GNUNET_GETOPT_OPTION_END
1491 return (GNUNET_OK ==
1492 GNUNET_PROGRAM_run (argc, argv, "gnunet-daemon-exit",
1494 ("Daemon to run to provide an IP exit node for the VPN"),
1495 options, &run, NULL)) ? ret : 1;
1499 /* end of gnunet-daemon-exit.c */