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-vpn.c
24 * @author Philipp Toelke
27 #include "gnunet_getopt_lib.h"
28 #include "gnunet_program_lib.h"
29 #include "gnunet-vpn-packet.h"
30 #include "gnunet_common.h"
31 #include "gnunet_protocols.h"
32 #include <gnunet_mesh_service.h>
33 #include "gnunet_client_lib.h"
34 #include "gnunet_container_lib.h"
35 #include "gnunet_constants.h"
36 #include <block_dns.h>
37 #include "gnunet-daemon-vpn-helper.h"
38 #include "gnunet-daemon-vpn-dns.h"
39 #include "gnunet-daemon-vpn.h"
40 #include "gnunet-vpn-checksum.h"
42 const struct GNUNET_CONFIGURATION_Handle *cfg;
43 struct GNUNET_MESH_Handle *mesh_handle;
44 struct GNUNET_CONTAINER_MultiHashMap* hashmap;
52 * This hashmap contains the mapping from peer, service-descriptor,
53 * source-port and destination-port to a socket
55 static struct GNUNET_CONTAINER_MultiHashMap *udp_connections;
58 * Function scheduled as very last function, cleans up after us
62 cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
63 GNUNET_assert (0 != (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
66 cleanup_helper(helper_handle);
68 /* close the connection to the service-dns */
69 if (dns_connection != NULL)
71 GNUNET_CLIENT_disconnect (dns_connection, GNUNET_NO);
72 dns_connection = NULL;
75 if (mesh_handle != NULL)
77 GNUNET_MESH_disconnect(mesh_handle);
84 * @return the hash of the IP-Address if a mapping exists, NULL otherwise
87 address_mapping_exists(unsigned char addr[]) {
88 GNUNET_HashCode* key = GNUNET_malloc(sizeof(GNUNET_HashCode));
89 unsigned char* k = (unsigned char*)key;
90 memset(key, 0, sizeof(GNUNET_HashCode));
92 for (i = 0; i < 16; i++)
95 if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(hashmap, key))
105 send_icmp_response(void* cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
106 struct ip6_icmp* request = cls;
108 struct ip6_icmp* response = alloca(ntohs(request->shdr.size));
109 GNUNET_assert(response != NULL);
110 memset(response, 0, ntohs(request->shdr.size));
112 response->shdr.size = request->shdr.size;
113 response->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
115 response->tun.flags = 0;
116 response->tun.type = htons(0x86dd);
118 response->ip6_hdr.hoplmt = 255;
119 response->ip6_hdr.paylgth = request->ip6_hdr.paylgth;
120 response->ip6_hdr.nxthdr = 0x3a;
121 response->ip6_hdr.version = 6;
122 memcpy(&response->ip6_hdr.sadr, &request->ip6_hdr.dadr, 16);
123 memcpy(&response->ip6_hdr.dadr, &request->ip6_hdr.sadr, 16);
125 response->icmp_hdr.code = 0;
126 response->icmp_hdr.type = 0x81;
128 /* Magic, more Magic! */
129 response->icmp_hdr.chks = request->icmp_hdr.chks - 0x1;
131 /* Copy the rest of the packet */
132 memcpy(response+1, request+1, ntohs(request->shdr.size) - sizeof(struct ip6_icmp));
134 write_to_helper(response, ntohs(response->shdr.size));
136 GNUNET_free(request);
140 * cls is the pointer to a GNUNET_MessageHeader that is
141 * followed by the service-descriptor and the packet that should be sent;
144 send_pkt_to_peer_notify_callback (void *cls, size_t size, void *buf)
146 struct GNUNET_MESH_Tunnel **tunnel = cls;
147 struct GNUNET_MessageHeader *hdr =
148 (struct GNUNET_MessageHeader *) (tunnel + 1);
149 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "send_pkt_to_peer_notify_callback: buf = %x; size = %u;\n", buf, size);
150 GNUNET_assert (size >= ntohs (hdr->size));
151 memcpy (buf, hdr, ntohs (hdr->size));
152 size = ntohs(hdr->size);
154 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sent!\n");
159 port_in_ports (uint64_t ports, uint16_t port)
161 uint16_t *ps = (uint16_t *) & ports;
162 return ps[0] == port || ps[1] == port || ps[2] == port || ps[3] == port;
166 send_pkt_to_peer (void *cls,
167 const struct GNUNET_PeerIdentity *peer,
168 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
170 if (peer == NULL) return;
171 struct GNUNET_MESH_Tunnel **tunnel = cls;
172 struct GNUNET_MessageHeader *hdr =
173 (struct GNUNET_MessageHeader *) (tunnel + 1);
175 GNUNET_assert(NULL != tunnel);
176 GNUNET_assert(NULL != *tunnel);
178 GNUNET_MESH_notify_transmit_ready (*tunnel,
181 GNUNET_TIME_relative_divide(GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
182 (const struct GNUNET_PeerIdentity *)NULL,
184 send_pkt_to_peer_notify_callback,
189 * Create a new Address from an answer-packet
192 new_ip6addr(unsigned char* buf, const GNUNET_HashCode *peer, const GNUNET_HashCode *service_desc) { /* {{{ */
194 unsigned long long ipv6prefix;
195 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
196 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_number(cfg, "vpn", "IPV6PREFIX", &ipv6prefix));
197 GNUNET_assert(ipv6prefix < 127);
198 ipv6prefix = (ipv6prefix + 7)/8;
200 inet_pton (AF_INET6, ipv6addr, buf);
201 GNUNET_free(ipv6addr);
203 int peer_length = 16 - ipv6prefix - 6;
204 if (peer_length <= 0)
207 int service_length = 16 - ipv6prefix - peer_length;
208 if (service_length <= 0)
211 memcpy(buf+ipv6prefix, service_desc, service_length);
212 memcpy(buf+ipv6prefix+service_length, peer, peer_length);
217 * This gets scheduled with cls pointing to an answer_packet and does everything
218 * needed in order to send it to the helper.
220 * At the moment this means "inventing" and IPv6-Address for .gnunet-services and
221 * doing nothing for "real" services.
224 process_answer(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tc) {
225 struct answer_packet* pkt = cls;
226 struct answer_packet_list* list;
228 /* This answer is about a .gnunet-service
230 * It contains an almost complete DNS-Response, we have to fill in the ip
231 * at the offset pkt->addroffset
233 if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_SERVICE)
235 pkt->subtype = GNUNET_DNS_ANSWER_TYPE_IP;
238 memset(&key, 0, sizeof(GNUNET_HashCode));
240 unsigned char* c = ((unsigned char*)pkt)+ntohs(pkt->addroffset);
241 unsigned char* k = (unsigned char*)&key;
242 new_ip6addr(c, &pkt->service_descr.peer, &pkt->service_descr.service_descriptor);
244 * Copy the newly generated ip-address to the key backwarts (as only the first part is hashed)
247 for (i = 0; i < 16; i++)
250 uint16_t namelen = strlen((char*)pkt->data+12)+1;
252 struct map_entry* value = GNUNET_malloc(sizeof(struct map_entry) + namelen);
253 char* name = (char*)(value +1);
255 value->namelen = namelen;
256 memcpy(name, pkt->data+12, namelen);
258 memcpy(&value->desc, &pkt->service_descr, sizeof(struct GNUNET_vpn_service_descriptor));
260 memset(value->additional_ports, 0, 8192);
262 /* FIXME save this to heap, too */
264 GNUNET_CONTAINER_multihashmap_contains (hashmap, &key))
265 GNUNET_CONTAINER_multihashmap_put (hashmap, &key, value,
266 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
271 list = GNUNET_malloc(htons(pkt->hdr.size) + 2*sizeof(struct answer_packet_list*));
273 memcpy(&list->pkt, pkt, htons(pkt->hdr.size));
276 else if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_REV)
279 memset(&key, 0, sizeof key);
280 unsigned char* k = (unsigned char*)&key;
281 unsigned char* s = pkt->data+12;
283 /* Whoever designed the reverse IPv6-lookup is batshit insane */
284 for (i = 0; i < 16; i++)
286 unsigned char c1 = s[(4*i)+1];
287 unsigned char c2 = s[(4*i)+3];
291 k[i] = c1 - 87; /* 87 is the difference between 'a' and 10 */
293 k[i] += 16*(c2 - '0');
295 k[i] += 16*(c2 - 87);
298 /* FIXME: update costs in heap */
299 struct map_entry* map_entry = GNUNET_CONTAINER_multihashmap_get(hashmap, &key);
300 uint16_t offset = ntohs(pkt->addroffset);
302 if (map_entry == NULL)
308 unsigned short namelen = htons(map_entry->namelen);
309 char* name = (char*)(map_entry + 1);
311 list = GNUNET_malloc(2*sizeof(struct answer_packet_list*) + offset + 2 + ntohs(namelen));
313 struct answer_packet* rpkt = &list->pkt;
315 /* The offset points to the first byte belonging to the address */
316 memcpy(rpkt, pkt, offset - 1);
318 rpkt->subtype = GNUNET_DNS_ANSWER_TYPE_IP;
319 rpkt->hdr.size = ntohs(offset + 2 + ntohs(namelen));
321 memcpy(((char*)rpkt)+offset, &namelen, 2);
322 memcpy(((char*)rpkt)+offset+2, name, ntohs(namelen));
325 else if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_IP)
327 list = GNUNET_malloc(htons(pkt->hdr.size) + 2*sizeof(struct answer_packet_list*));
328 memcpy(&list->pkt, pkt, htons(pkt->hdr.size));
330 /* TODO GNUNET_DNS_ANSWER_TYPE_REMOTE */
340 GNUNET_CONTAINER_DLL_insert_after(answer_proc_head, answer_proc_tail, answer_proc_tail, list);
342 schedule_helper_write(GNUNET_TIME_UNIT_FOREVER_REL, NULL);
348 * Sets a bit active in a bitArray.
350 * @param bitArray memory area to set the bit in
351 * @param bitIdx which bit to set
354 setBit (char *bitArray, unsigned int bitIdx)
357 unsigned int targetBit;
359 arraySlot = bitIdx / 8;
360 targetBit = (1L << (bitIdx % 8));
361 bitArray[arraySlot] |= targetBit;
365 * Clears a bit from bitArray.
367 * @param bitArray memory area to set the bit in
368 * @param bitIdx which bit to unset
371 clearBit (char *bitArray, unsigned int bitIdx)
374 unsigned int targetBit;
377 targetBit = (1L << (bitIdx % 8));
378 bitArray[slot] = bitArray[slot] & (~targetBit);
382 * Checks if a bit is active in the bitArray
384 * @param bitArray memory area to set the bit in
385 * @param bitIdx which bit to test
386 * @return GNUNET_YES if the bit is set, GNUNET_NO if not.
389 testBit (char *bitArray, unsigned int bitIdx)
392 unsigned int targetBit;
395 targetBit = (1L << (bitIdx % 8));
396 if (bitArray[slot] & targetBit)
403 * @brief Add the port to the list of additional ports in the map_entry
405 * @param me the map_entry
406 * @param port the port in host-byte-order
409 add_additional_port (struct map_entry *me, uint16_t port)
411 setBit(me->additional_ports, port);
415 receive_udp_back (void *cls, struct GNUNET_MESH_Tunnel* tunnel,
417 const struct GNUNET_PeerIdentity *sender,
418 const struct GNUNET_MessageHeader *message,
419 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
421 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
422 struct udp_pkt *pkt = (struct udp_pkt *) (desc + 1);
423 const struct GNUNET_PeerIdentity* other = GNUNET_MESH_get_peer(tunnel);
425 size_t size = sizeof(struct ip6_udp) + ntohs(pkt->len) - 1 - sizeof(struct udp_pkt);
427 struct ip6_udp* pkt6 = alloca(size);
429 GNUNET_assert(pkt6 != NULL);
431 new_ip6addr(pkt6->ip6_hdr.sadr, &other->hashPubKey, desc);
433 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Relaying calc:%d gnu:%d udp:%d bytes!\n", size, ntohs(message->size), ntohs(pkt->len));
435 pkt6->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
436 pkt6->shdr.size = htons(size);
439 pkt6->tun.type = htons(0x86dd);
441 pkt6->ip6_hdr.version = 6;
442 pkt6->ip6_hdr.tclass_h = 0;
443 pkt6->ip6_hdr.tclass_l = 0;
444 pkt6->ip6_hdr.flowlbl = 0;
445 pkt6->ip6_hdr.paylgth = pkt->len;
446 pkt6->ip6_hdr.nxthdr = 0x11;
447 pkt6->ip6_hdr.hoplmt = 0xff;
451 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
452 inet_pton (AF_INET6, ipv6addr, pkt6->ip6_hdr.dadr);
453 GNUNET_free(ipv6addr);
455 memcpy(&pkt6->udp_hdr, pkt, ntohs(pkt->len));
457 GNUNET_HashCode* key = address_mapping_exists(pkt6->ip6_hdr.sadr);
458 GNUNET_assert (key != NULL);
460 /* FIXME: update costs in heap */
461 struct map_entry *me = GNUNET_CONTAINER_multihashmap_get(hashmap, key);
465 GNUNET_assert (me != NULL);
466 GNUNET_assert (me->desc.service_type & htonl(GNUNET_DNS_SERVICE_TYPE_UDP));
467 if (!port_in_ports(me->desc.ports, pkt6->udp_hdr.spt) &&
468 !testBit(me->additional_ports, ntohs(pkt6->udp_hdr.spt))) {
469 add_additional_port(me, ntohs(pkt6->udp_hdr.spt));
472 pkt6->udp_hdr.crc = 0;
474 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->ip6_hdr.sadr, 16);
475 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->ip6_hdr.dadr, 16);
476 uint32_t tmp = (pkt6->udp_hdr.len & 0xffff);
477 sum = calculate_checksum_update(sum, (uint16_t*)&tmp, 4);
478 tmp = htons(((pkt6->ip6_hdr.nxthdr & 0x00ff)));
479 sum = calculate_checksum_update(sum, (uint16_t*)&tmp, 4);
481 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->udp_hdr, ntohs(pkt->len));
482 pkt6->udp_hdr.crc = calculate_checksum_end(sum);
484 write_to_helper(pkt6, size);
490 receive_tcp_back (void *cls, struct GNUNET_MESH_Tunnel* tunnel,
492 const struct GNUNET_PeerIdentity *sender,
493 const struct GNUNET_MessageHeader *message,
494 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
496 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
497 struct tcp_pkt *pkt = (struct tcp_pkt *) (desc + 1);
498 const struct GNUNET_PeerIdentity* other = GNUNET_MESH_get_peer(tunnel);
500 size_t pktlen = ntohs(message->size) - sizeof(struct GNUNET_MessageHeader) - sizeof(GNUNET_HashCode);
501 size_t size = pktlen + sizeof(struct ip6_tcp) - 1;
503 struct ip6_tcp* pkt6 = alloca(size);
505 GNUNET_assert(pkt6 != NULL);
507 new_ip6addr(pkt6->ip6_hdr.sadr, &other->hashPubKey, desc);
509 pkt6->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
510 pkt6->shdr.size = htons(size);
513 pkt6->tun.type = htons(0x86dd);
515 pkt6->ip6_hdr.version = 6;
516 pkt6->ip6_hdr.tclass_h = 0;
517 pkt6->ip6_hdr.tclass_l = 0;
518 pkt6->ip6_hdr.flowlbl = 0;
519 pkt6->ip6_hdr.paylgth = htons(pktlen);
520 pkt6->ip6_hdr.nxthdr = 0x06;
521 pkt6->ip6_hdr.hoplmt = 0xff;
525 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
526 inet_pton (AF_INET6, ipv6addr, pkt6->ip6_hdr.dadr);
527 GNUNET_free(ipv6addr);
529 memcpy(&pkt6->tcp_hdr, pkt, pktlen);
531 GNUNET_HashCode* key = address_mapping_exists(pkt6->ip6_hdr.sadr);
532 GNUNET_assert (key != NULL);
534 /* FIXME: update costs in heap */
535 struct map_entry *me = GNUNET_CONTAINER_multihashmap_get(hashmap, key);
539 GNUNET_assert (me != NULL);
540 GNUNET_assert (me->desc.service_type & htonl(GNUNET_DNS_SERVICE_TYPE_TCP));
542 pkt6->tcp_hdr.crc = 0;
546 calculate_checksum_update (sum, (uint16_t *) & pkt6->ip6_hdr.sadr, 16);
548 calculate_checksum_update (sum, (uint16_t *) & pkt6->ip6_hdr.dadr, 16);
550 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
551 tmp = htonl (((pkt6->ip6_hdr.nxthdr & 0x000000ff)));
552 sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4);
555 calculate_checksum_update (sum, (uint16_t *) & pkt6->tcp_hdr,
556 ntohs (pkt6->ip6_hdr.paylgth));
557 pkt6->tcp_hdr.crc = calculate_checksum_end (sum);
559 write_to_helper(pkt6, size);
565 * Main function that will be run by the scheduler.
568 * @param args remaining command-line arguments
569 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
570 * @param cfg_ configuration
576 const struct GNUNET_CONFIGURATION_Handle *cfg_)
578 const static struct GNUNET_MESH_MessageHandler handlers[] = {
579 {receive_udp_back, GNUNET_MESSAGE_TYPE_SERVICE_UDP_BACK, 0},
580 {receive_tcp_back, GNUNET_MESSAGE_TYPE_SERVICE_TCP_BACK, 0},
583 mesh_handle = GNUNET_MESH_connect(cfg_,
590 hashmap = GNUNET_CONTAINER_multihashmap_create(65536);
591 udp_connections = GNUNET_CONTAINER_multihashmap_create(65536);
592 GNUNET_SCHEDULER_TaskIdentifier conn_task = GNUNET_SCHEDULER_add_now (connect_to_service_dns, NULL);
593 GNUNET_SCHEDULER_add_after (conn_task, start_helper_and_schedule, NULL);
594 GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
598 * The main function to obtain template from gnunetd.
600 * @param argc number of arguments from the command line
601 * @param argv command line arguments
602 * @return 0 ok, 1 on error
605 main (int argc, char *const *argv) {
606 static const struct GNUNET_GETOPT_CommandLineOption options[] = {
607 GNUNET_GETOPT_OPTION_END
611 GNUNET_PROGRAM_run (argc,
614 gettext_noop ("help text"),
615 options, &run, NULL)) ? ret : 1;
618 /* end of gnunet-daemon-vpn.c */