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-vpn-pretty-print.h"
31 #include "gnunet_common.h"
32 #include "gnunet_protocols.h"
33 #include <gnunet_mesh_service.h>
34 #include "gnunet_client_lib.h"
35 #include "gnunet_container_lib.h"
36 #include "gnunet_constants.h"
37 #include <block_dns.h>
38 #include "gnunet-daemon-vpn-helper.h"
39 #include "gnunet-daemon-vpn-dns.h"
40 #include "gnunet-daemon-vpn.h"
41 #include "gnunet-vpn-checksum.h"
43 const struct GNUNET_CONFIGURATION_Handle *cfg;
44 struct GNUNET_MESH_Handle *mesh_handle;
45 struct GNUNET_CONTAINER_MultiHashMap* hashmap;
53 * This hashmap contains the mapping from peer, service-descriptor,
54 * source-port and destination-port to a socket
56 static struct GNUNET_CONTAINER_MultiHashMap *udp_connections;
59 * Function scheduled as very last function, cleans up after us
63 cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
64 GNUNET_assert (0 != (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
67 cleanup_helper(helper_handle);
69 /* close the connection to the service-dns */
70 if (dns_connection != NULL)
72 GNUNET_CLIENT_disconnect (dns_connection, GNUNET_NO);
73 dns_connection = NULL;
76 if (mesh_handle != NULL)
78 GNUNET_MESH_disconnect(mesh_handle);
85 * @return the hash of the IP-Address if a mapping exists, NULL otherwise
88 address_mapping_exists(unsigned char addr[]) {
89 GNUNET_HashCode* key = GNUNET_malloc(sizeof(GNUNET_HashCode));
90 unsigned char* k = (unsigned char*)key;
91 memset(key, 0, sizeof(GNUNET_HashCode));
93 for (i = 0; i < 16; i++)
96 if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(hashmap, key))
106 send_icmp_response(void* cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
107 struct ip6_icmp* request = cls;
109 struct ip6_icmp* response = alloca(ntohs(request->shdr.size));
110 GNUNET_assert(response != NULL);
111 memset(response, 0, ntohs(request->shdr.size));
113 response->shdr.size = request->shdr.size;
114 response->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
116 response->tun.flags = 0;
117 response->tun.type = htons(0x86dd);
119 response->ip6_hdr.hoplmt = 255;
120 response->ip6_hdr.paylgth = request->ip6_hdr.paylgth;
121 response->ip6_hdr.nxthdr = 0x3a;
122 response->ip6_hdr.version = 6;
123 memcpy(&response->ip6_hdr.sadr, &request->ip6_hdr.dadr, 16);
124 memcpy(&response->ip6_hdr.dadr, &request->ip6_hdr.sadr, 16);
126 response->icmp_hdr.code = 0;
127 response->icmp_hdr.type = 0x81;
129 /* Magic, more Magic! */
130 response->icmp_hdr.chks = request->icmp_hdr.chks - 0x1;
132 /* Copy the rest of the packet */
133 memcpy(response+1, request+1, ntohs(request->shdr.size) - sizeof(struct ip6_icmp));
135 write_to_helper(response, ntohs(response->shdr.size));
137 GNUNET_free(request);
141 * cls is the pointer to a GNUNET_MessageHeader that is
142 * followed by the service-descriptor and the udp-packet that should be sent;
145 send_udp_to_peer_notify_callback (void *cls, size_t size, void *buf)
147 struct GNUNET_MESH_Tunnel **tunnel = cls;
148 struct GNUNET_MessageHeader *hdr =
149 (struct GNUNET_MessageHeader *) (tunnel + 1);
150 GNUNET_HashCode *hc = (GNUNET_HashCode *) (hdr + 1);
151 struct udp_pkt *udp = (struct udp_pkt *) (hc + 1);
152 hdr->size = htons (sizeof (struct GNUNET_MessageHeader) +
153 sizeof (GNUNET_HashCode) + ntohs (udp->len));
154 hdr->type = ntohs (GNUNET_MESSAGE_TYPE_SERVICE_UDP);
155 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "send_udp_to_peer_notify_callback: buf = %x; size = %u;\n", buf, size);
156 GNUNET_assert (size >= ntohs (hdr->size));
157 memcpy (buf, hdr, ntohs (hdr->size));
158 size = ntohs(hdr->size);
160 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sent!\n");
165 port_in_ports (uint64_t ports, uint16_t port)
167 uint16_t *ps = (uint16_t *) & ports;
168 return ps[0] == port || ps[1] == port || ps[2] == port || ps[3] == port;
172 send_udp_to_peer (void *cls,
173 const struct GNUNET_PeerIdentity *peer,
174 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
176 if (peer == NULL) return;
177 struct GNUNET_MESH_Tunnel **tunnel = cls;
178 struct GNUNET_MessageHeader *hdr =
179 (struct GNUNET_MessageHeader *) (tunnel + 1);
180 GNUNET_HashCode *hc = (GNUNET_HashCode *) (hdr + 1);
181 struct udp_pkt *udp = (struct udp_pkt *) (hc + 1);
182 GNUNET_MESH_notify_transmit_ready (*tunnel,
185 GNUNET_TIME_relative_divide(GNUNET_CONSTANTS_MAX_CORK_DELAY, 2),
187 (struct GNUNET_MessageHeader) +
188 sizeof (GNUNET_HashCode) +
190 send_udp_to_peer_notify_callback,
195 * Create a new Address from an answer-packet
198 new_ip6addr(unsigned char* buf, const GNUNET_HashCode *peer, const GNUNET_HashCode *service_desc) { /* {{{ */
200 unsigned long long ipv6prefix;
201 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
202 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_number(cfg, "vpn", "IPV6PREFIX", &ipv6prefix));
203 GNUNET_assert(ipv6prefix < 127);
204 ipv6prefix = (ipv6prefix + 7)/8;
206 inet_pton (AF_INET6, ipv6addr, buf);
207 GNUNET_free(ipv6addr);
209 int peer_length = 16 - ipv6prefix - 6;
210 if (peer_length <= 0)
213 int service_length = 16 - ipv6prefix - peer_length;
214 if (service_length <= 0)
217 memcpy(buf+ipv6prefix, service_desc, service_length);
218 memcpy(buf+ipv6prefix+service_length, peer, peer_length);
223 * This gets scheduled with cls pointing to an answer_packet and does everything
224 * needed in order to send it to the helper.
226 * At the moment this means "inventing" and IPv6-Address for .gnunet-services and
227 * doing nothing for "real" services.
230 process_answer(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tc) {
231 struct answer_packet* pkt = cls;
232 struct answer_packet_list* list;
234 /* This answer is about a .gnunet-service
236 * It contains an almost complete DNS-Response, we have to fill in the ip
237 * at the offset pkt->addroffset
240 if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_SERVICE)
242 pkt->subtype = GNUNET_DNS_ANSWER_TYPE_IP;
245 memset(&key, 0, sizeof(GNUNET_HashCode));
247 unsigned char* c = ((unsigned char*)pkt)+ntohs(pkt->addroffset);
248 unsigned char* k = (unsigned char*)&key;
249 new_ip6addr(c, &pkt->service_descr.peer, &pkt->service_descr.service_descriptor);
251 * Copy the newly generated ip-address to the key backwarts (as only the first part is hashed)
254 for (i = 0; i < 16; i++)
257 uint16_t namelen = strlen((char*)pkt->data+12)+1;
259 struct map_entry* value = GNUNET_malloc(sizeof(struct map_entry) + namelen);
260 char* name = (char*)(value +1);
262 value->namelen = namelen;
263 memcpy(name, pkt->data+12, namelen);
265 memcpy(&value->desc, &pkt->service_descr, sizeof(struct GNUNET_vpn_service_descriptor));
267 memset(value->additional_ports, 0, 8192);
270 GNUNET_CONTAINER_multihashmap_contains (hashmap, &key))
271 GNUNET_CONTAINER_multihashmap_put (hashmap, &key, value,
272 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
277 list = GNUNET_malloc(htons(pkt->hdr.size) + 2*sizeof(struct answer_packet_list*));
279 memcpy(&list->pkt, pkt, htons(pkt->hdr.size));
282 else if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_REV)
285 memset(&key, 0, sizeof key);
286 unsigned char* k = (unsigned char*)&key;
287 unsigned char* s = pkt->data+12;
289 /* Whoever designed the reverse IPv6-lookup is batshit insane */
290 for (i = 0; i < 16; i++)
292 unsigned char c1 = s[(4*i)+1];
293 unsigned char c2 = s[(4*i)+3];
297 k[i] = c1 - 87; /* 87 is the difference between 'a' and 10 */
299 k[i] += 16*(c2 - '0');
301 k[i] += 16*(c2 - 87);
304 struct map_entry* map_entry = GNUNET_CONTAINER_multihashmap_get(hashmap, &key);
305 uint16_t offset = ntohs(pkt->addroffset);
307 if (map_entry == NULL)
313 unsigned short namelen = htons(map_entry->namelen);
314 char* name = (char*)(map_entry + 1);
316 list = GNUNET_malloc(2*sizeof(struct answer_packet_list*) + offset + 2 + ntohs(namelen));
318 struct answer_packet* rpkt = &list->pkt;
320 /* The offset points to the first byte belonging to the address */
321 memcpy(rpkt, pkt, offset - 1);
323 rpkt->subtype = GNUNET_DNS_ANSWER_TYPE_IP;
324 rpkt->hdr.size = ntohs(offset + 2 + ntohs(namelen));
326 memcpy(((char*)rpkt)+offset, &namelen, 2);
327 memcpy(((char*)rpkt)+offset+2, name, ntohs(namelen));
330 else if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_IP)
332 list = GNUNET_malloc(htons(pkt->hdr.size) + 2*sizeof(struct answer_packet_list*));
333 memcpy(&list->pkt, pkt, htons(pkt->hdr.size));
344 GNUNET_CONTAINER_DLL_insert_after(answer_proc_head, answer_proc_tail, answer_proc_tail, list);
346 schedule_helper_write(GNUNET_TIME_UNIT_FOREVER_REL, NULL);
352 * Sets a bit active in a bitArray.
354 * @param bitArray memory area to set the bit in
355 * @param bitIdx which bit to set
358 setBit (char *bitArray, unsigned int bitIdx)
361 unsigned int targetBit;
363 arraySlot = bitIdx / 8;
364 targetBit = (1L << (bitIdx % 8));
365 bitArray[arraySlot] |= targetBit;
369 * Clears a bit from bitArray.
371 * @param bitArray memory area to set the bit in
372 * @param bitIdx which bit to unset
375 clearBit (char *bitArray, unsigned int bitIdx)
378 unsigned int targetBit;
381 targetBit = (1L << (bitIdx % 8));
382 bitArray[slot] = bitArray[slot] & (~targetBit);
386 * Checks if a bit is active in the bitArray
388 * @param bitArray memory area to set the bit in
389 * @param bitIdx which bit to test
390 * @return GNUNET_YES if the bit is set, GNUNET_NO if not.
393 testBit (char *bitArray, unsigned int bitIdx)
396 unsigned int targetBit;
399 targetBit = (1L << (bitIdx % 8));
400 if (bitArray[slot] & targetBit)
407 * @brief Add the port to the list of additional ports in the map_entry
409 * @param me the map_entry
410 * @param port the port in host-byte-order
413 add_additional_port (struct map_entry *me, uint16_t port)
415 setBit(me->additional_ports, port);
419 receive_udp_back (void *cls, struct GNUNET_MESH_Tunnel* tunnel,
421 const struct GNUNET_PeerIdentity *sender,
422 const struct GNUNET_MessageHeader *message,
423 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
425 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
426 struct udp_pkt *pkt = (struct udp_pkt *) (desc + 1);
427 const struct GNUNET_PeerIdentity* other = GNUNET_MESH_get_peer(tunnel);
429 size_t size = sizeof(struct ip6_udp) + ntohs(pkt->len) - 1 - sizeof(struct udp_pkt);
431 struct ip6_udp* pkt6 = alloca(size);
433 GNUNET_assert(pkt6 != NULL);
435 new_ip6addr(pkt6->ip6_hdr.sadr, &other->hashPubKey, desc);
437 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Relaying calc:%d gnu:%d udp:%d bytes!\n", size, ntohs(message->size), ntohs(pkt->len));
439 pkt6->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
440 pkt6->shdr.size = htons(size);
443 pkt6->tun.type = htons(0x86dd);
445 pkt6->ip6_hdr.version = 6;
446 pkt6->ip6_hdr.tclass_h = 0;
447 pkt6->ip6_hdr.tclass_l = 0;
448 pkt6->ip6_hdr.flowlbl = 0;
449 pkt6->ip6_hdr.paylgth = pkt->len;
450 pkt6->ip6_hdr.nxthdr = 0x11;
451 pkt6->ip6_hdr.hoplmt = 0xff;
455 GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
456 inet_pton (AF_INET6, ipv6addr, pkt6->ip6_hdr.dadr);
457 GNUNET_free(ipv6addr);
459 memcpy(&pkt6->udp_hdr, pkt, ntohs(pkt->len));
461 GNUNET_HashCode* key = address_mapping_exists(pkt6->ip6_hdr.sadr);
462 GNUNET_assert (key != NULL);
464 struct map_entry *me = GNUNET_CONTAINER_multihashmap_get(hashmap, key);
468 GNUNET_assert (me != NULL);
469 GNUNET_assert (me->desc.service_type & htonl(GNUNET_DNS_SERVICE_TYPE_UDP));
470 if (!port_in_ports(me->desc.ports, pkt6->udp_hdr.spt) &&
471 !testBit(me->additional_ports, ntohs(pkt6->udp_hdr.spt))) {
472 add_additional_port(me, ntohs(pkt6->udp_hdr.spt));
475 pkt6->udp_hdr.crc = 0;
477 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->ip6_hdr.sadr, 16);
478 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->ip6_hdr.dadr, 16);
479 uint32_t tmp = (pkt6->udp_hdr.len & 0xffff);
480 sum = calculate_checksum_update(sum, (uint16_t*)&tmp, 4);
481 tmp = htons(((pkt6->ip6_hdr.nxthdr & 0x00ff)));
482 sum = calculate_checksum_update(sum, (uint16_t*)&tmp, 4);
484 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->udp_hdr, ntohs(pkt->len));
485 pkt6->udp_hdr.crc = calculate_checksum_end(sum);
487 write_to_helper(pkt6, size);
492 void init_mesh (void* cls, struct GNUNET_MESH_Handle* server, const struct GNUNET_PeerIdentity* my_identity, const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *pubkey) {
493 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connected to MESH, I am %x\n", *((unsigned long*)my_identity));
496 void connect_mesh (void* cls, const struct GNUNET_PeerIdentity* peer, const struct GNUNET_TRANSPORT_ATS_Information *atsi) {
497 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connected to peer %x\n", *((unsigned long*)peer));
501 * Main function that will be run by the scheduler.
504 * @param args remaining command-line arguments
505 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
506 * @param cfg_ configuration
512 const struct GNUNET_CONFIGURATION_Handle *cfg_)
514 const static struct GNUNET_MESH_MessageHandler handlers[] = {
515 {receive_udp_back, GNUNET_MESSAGE_TYPE_SERVICE_UDP_BACK, 0},
518 mesh_handle = GNUNET_MESH_connect(cfg_,
524 hashmap = GNUNET_CONTAINER_multihashmap_create(65536);
525 udp_connections = GNUNET_CONTAINER_multihashmap_create(65536);
526 GNUNET_SCHEDULER_TaskIdentifier conn_task = GNUNET_SCHEDULER_add_now (connect_to_service_dns, NULL);
527 GNUNET_SCHEDULER_add_after (conn_task, start_helper_and_schedule, NULL);
528 GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
532 * The main function to obtain template from gnunetd.
534 * @param argc number of arguments from the command line
535 * @param argv command line arguments
536 * @return 0 ok, 1 on error
539 main (int argc, char *const *argv) {
540 static const struct GNUNET_GETOPT_CommandLineOption options[] = {
541 GNUNET_GETOPT_OPTION_END
545 GNUNET_PROGRAM_run (argc,
548 gettext_noop ("help text"),
549 options, &run, NULL)) ? ret : 1;
552 /* end of gnunet-daemon-vpn.c */