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_os_lib.h"
30 #include "gnunet-vpn-helper-p.h"
31 #include "gnunet-vpn-packet.h"
32 #include "gnunet-vpn-pretty-print.h"
33 #include "gnunet_common.h"
34 #include "gnunet_protocols.h"
35 #include "gnunet_server_lib.h"
36 #include "gnunet-service-dns-p.h"
37 #include "gnunet_core_service.h"
38 #include "gnunet_client_lib.h"
39 #include "gnunet_container_lib.h"
40 #include "block_dns.h"
48 * The configuration to use
50 static const struct GNUNET_CONFIGURATION_Handle *cfg;
53 * PipeHandle to receive data from the helper
55 static struct GNUNET_DISK_PipeHandle* helper_in;
58 * PipeHandle to send data to the helper
60 static struct GNUNET_DISK_PipeHandle* helper_out;
63 * FileHandle to receive data from the helper
65 static const struct GNUNET_DISK_FileHandle* fh_from_helper;
68 * FileHandle to send data to the helper
70 static const struct GNUNET_DISK_FileHandle* fh_to_helper;
73 * The Message-Tokenizer that tokenizes the messages comming from the helper
75 static struct GNUNET_SERVER_MessageStreamTokenizer* mst;
78 * The connection to the service-dns
80 static struct GNUNET_CLIENT_Connection *dns_connection;
83 * A flag to show that the service-dns has to rehijack the outbound dns-packets
85 * This gets set when the helper restarts as the routing-tables are flushed when
86 * the interface vanishes.
88 static unsigned char restart_hijack;
91 * The process id of the helper
93 static struct GNUNET_OS_Process *helper_proc;
96 * a list of outgoing dns-query-packets
98 static struct query_packet_list *head;
101 * The last element of the list of outgoing dns-query-packets
103 static struct query_packet_list *tail;
106 * A list of processed dns-responses.
108 * "processed" means that the packet is complete and can be sent out via udp
111 static struct answer_packet_list *answer_proc_head;
114 * The last element of the list of processed dns-responses.
116 static struct answer_packet_list *answer_proc_tail;
119 * The hashmap containing the mappings from ipv6-addresses to gnunet-descriptors
121 static struct GNUNET_CONTAINER_MultiHashMap* hashmap;
124 * This hashmap contains the mapping from peer, service-descriptor,
125 * source-port and destination-port to a socket
127 static struct GNUNET_CONTAINER_MultiHashMap *udp_connections;
132 static struct GNUNET_CORE_Handle *core_handle;
135 struct GNUNET_vpn_service_descriptor desc;
137 uint64_t additional_ports;
144 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx);
145 static void dns_answer_handler(void* cls, const struct GNUNET_MessageHeader *msg);
148 * Callback called by notify_transmit_ready; sends dns-queries or rehijack-messages
153 send_query(void* cls, size_t size, void* buf) {
156 * Send the rehijack-message
158 if (restart_hijack == 1)
162 * The message is just a header
164 GNUNET_assert(sizeof(struct GNUNET_MessageHeader) <= size);
165 struct GNUNET_MessageHeader* hdr = buf;
166 len = sizeof(struct GNUNET_MessageHeader);
167 hdr->size = htons(len);
168 hdr->type = htons(GNUNET_MESSAGE_TYPE_REHIJACK);
172 struct query_packet_list* query = head;
173 len = ntohs(query->pkt.hdr.size);
175 GNUNET_assert(len <= size);
177 memcpy(buf, &query->pkt.hdr, len);
179 GNUNET_CONTAINER_DLL_remove (head, tail, query);
185 * Check whether more data is to be sent
189 GNUNET_CLIENT_notify_transmit_ready(dns_connection, ntohs(head->pkt.hdr.size), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
191 else if (restart_hijack == 1)
193 GNUNET_CLIENT_notify_transmit_ready(dns_connection, sizeof(struct GNUNET_MessageHeader), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
201 * Function scheduled as very last function, cleans up after us
205 cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
206 GNUNET_assert (0 != (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
208 /* stop the helper */
209 if (helper_proc != NULL)
211 GNUNET_OS_process_kill (helper_proc, SIGTERM);
212 GNUNET_OS_process_wait (helper_proc);
213 GNUNET_OS_process_close (helper_proc);
217 /* close the connection to the service-dns */
218 if (dns_connection != NULL)
220 GNUNET_CLIENT_disconnect (dns_connection, GNUNET_NO);
221 dns_connection = NULL;
224 if (core_handle != NULL)
226 GNUNET_CORE_disconnect(core_handle);
233 * Start the helper-process
237 start_helper_and_schedule(void *cls,
238 const struct GNUNET_SCHEDULER_TaskContext *tc) {
239 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
242 helper_in = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_YES, GNUNET_NO);
243 helper_out = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_NO, GNUNET_YES);
245 if (helper_in == NULL || helper_out == NULL) return;
247 helper_proc = GNUNET_OS_start_process(helper_in, helper_out, "gnunet-helper-vpn", "gnunet-helper-vpn", NULL);
249 fh_from_helper = GNUNET_DISK_pipe_handle (helper_out, GNUNET_DISK_PIPE_END_READ);
250 fh_to_helper = GNUNET_DISK_pipe_handle (helper_in, GNUNET_DISK_PIPE_END_WRITE);
252 GNUNET_DISK_pipe_close_end(helper_out, GNUNET_DISK_PIPE_END_WRITE);
253 GNUNET_DISK_pipe_close_end(helper_in, GNUNET_DISK_PIPE_END_READ);
255 /* Tell the dns-service to rehijack the dns-port
256 * The routing-table gets flushed if an interface disappears.
259 GNUNET_CLIENT_notify_transmit_ready(dns_connection, sizeof(struct GNUNET_MessageHeader), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
261 GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL, fh_from_helper, &helper_read, NULL);
266 * Restart the helper-process
270 restart_helper(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
272 GNUNET_OS_process_kill (helper_proc, SIGKILL);
273 GNUNET_OS_process_wait (helper_proc);
274 GNUNET_OS_process_close (helper_proc);
277 GNUNET_DISK_pipe_close(helper_in);
278 GNUNET_DISK_pipe_close(helper_out);
280 /* Restart the helper */
281 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, start_helper_and_schedule, NULL);
286 * Read from the helper-process
290 helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
291 /* no message can be bigger then 64k */
294 if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
297 int t = GNUNET_DISK_file_read(fh_from_helper, &buf, 65535);
299 /* On read-error, restart the helper */
301 GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Read error for header from vpn-helper: %m\n");
302 GNUNET_SCHEDULER_add_now(restart_helper, cls);
306 /* FIXME */ GNUNET_SERVER_mst_receive(mst, NULL, buf, t, 0, 0);
308 GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL, fh_from_helper, &helper_read, NULL);
312 static uint32_t calculate_checksum_update(uint32_t sum, uint16_t *hdr, short len) {
313 for(; len >= 2; len -= 2)
316 sum += *((unsigned char*)hdr);
320 static uint16_t calculate_checksum_end(uint32_t sum) {
322 sum = (sum >> 16) + (sum & 0xFFFF);
328 * Calculate the checksum of an IPv4-Header
331 calculate_ip_checksum(uint16_t* hdr, short len) {
332 uint32_t sum = calculate_checksum_update(0, hdr, len);
333 return calculate_checksum_end(sum);
337 * Send an dns-answer-packet to the helper
340 helper_write(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
341 if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
344 struct answer_packet_list* ans = answer_proc_head;
345 size_t len = ntohs(ans->pkt.hdr.size);
347 GNUNET_assert(ans->pkt.subtype == GNUNET_DNS_ANSWER_TYPE_IP);
349 GNUNET_assert (20 == sizeof (struct ip_hdr));
350 GNUNET_assert (8 == sizeof (struct udp_pkt));
351 size_t data_len = len - sizeof(struct answer_packet) + 1;
352 size_t net_len = sizeof(struct ip_hdr) + sizeof(struct udp_dns) + data_len;
353 size_t pkt_len = sizeof(struct GNUNET_MessageHeader) + sizeof(struct pkt_tun) + net_len;
355 struct ip_udp_dns* pkt = alloca(pkt_len);
356 memset(pkt, 0, pkt_len);
358 /* set the gnunet-header */
359 pkt->shdr.size = htons(pkt_len);
360 pkt->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
362 /* set the tun-header (no flags and ethertype of IPv4) */
364 pkt->tun.type = htons(0x0800);
366 /* set the ip-header */
367 pkt->ip_hdr.version = 4;
368 pkt->ip_hdr.hdr_lngth = 5;
369 pkt->ip_hdr.diff_serv = 0;
370 pkt->ip_hdr.tot_lngth = htons(net_len);
371 pkt->ip_hdr.ident = 0;
372 pkt->ip_hdr.flags = 0;
373 pkt->ip_hdr.frag_off = 0;
374 pkt->ip_hdr.ttl = 255;
375 pkt->ip_hdr.proto = 0x11; /* UDP */
376 pkt->ip_hdr.chks = 0; /* Will be calculated later*/
377 pkt->ip_hdr.sadr = ans->pkt.from;
378 pkt->ip_hdr.dadr = ans->pkt.to;
380 pkt->ip_hdr.chks = calculate_ip_checksum((uint16_t*)&pkt->ip_hdr, 5*4);
382 /* set the udp-header */
383 pkt->udp_dns.udp_hdr.spt = htons(53);
384 pkt->udp_dns.udp_hdr.dpt = ans->pkt.dst_port;
385 pkt->udp_dns.udp_hdr.len = htons(net_len - sizeof(struct ip_hdr));
386 pkt->udp_dns.udp_hdr.crc = 0; /* Optional for IPv4 */
388 memcpy(&pkt->udp_dns.data, ans->pkt.data, data_len);
390 GNUNET_CONTAINER_DLL_remove (answer_proc_head, answer_proc_tail, ans);
393 /* FIXME */ GNUNET_DISK_file_write(fh_to_helper, pkt, pkt_len);
395 /* if more packets are available, reschedule */
396 if (answer_proc_head != NULL)
397 GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL,
404 * @return the hash of the IP-Address if a mapping exists, NULL otherwise
406 static GNUNET_HashCode*
407 address_mapping_exists(unsigned char addr[]) {
408 GNUNET_HashCode* key = GNUNET_malloc(sizeof(GNUNET_HashCode));
409 unsigned char* k = (unsigned char*)key;
410 memset(key, 0, sizeof(GNUNET_HashCode));
412 for (i = 0; i < 16; i++)
415 if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains(hashmap, key))
425 send_icmp_response(void* cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
426 struct ip6_icmp* request = cls;
428 struct ip6_icmp* response = alloca(ntohs(request->shdr.size));
429 memset(response, 0, ntohs(request->shdr.size));
431 response->shdr.size = request->shdr.size;
432 response->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
434 response->tun.flags = 0;
435 response->tun.type = htons(0x86dd);
437 response->ip6_hdr.hoplmt = 255;
438 response->ip6_hdr.paylgth = request->ip6_hdr.paylgth;
439 response->ip6_hdr.nxthdr = 0x3a;
440 response->ip6_hdr.version = 6;
441 memcpy(&response->ip6_hdr.sadr, &request->ip6_hdr.dadr, 16);
442 memcpy(&response->ip6_hdr.dadr, &request->ip6_hdr.sadr, 16);
444 response->icmp_hdr.code = 0;
445 response->icmp_hdr.type = 0x81;
447 /* Magic, more Magic! */
448 response->icmp_hdr.chks = request->icmp_hdr.chks - 0x1;
450 /* Copy the rest of the packet */
451 memcpy(response+1, request+1, ntohs(request->shdr.size) - sizeof(struct ip6_icmp));
453 /* FIXME */ GNUNET_DISK_file_write(fh_to_helper, response, ntohs(response->shdr.size));
455 GNUNET_free(request);
459 * cls is the pointer to a GNUNET_MessageHeader that is
460 * followed by the service-descriptor and the udp-packet that should be sent;
463 handle_udp (void *cls, size_t size, void *buf)
465 struct GNUNET_PeerIdentity *peer = cls;
466 struct GNUNET_MessageHeader *hdr =
467 (struct GNUNET_MessageHeader *) (peer + 1);
468 GNUNET_HashCode *hc = (GNUNET_HashCode *) (hdr + 1);
469 struct udp_pkt *udp = (struct udp_pkt *) (hc + 1);
470 hdr->size = htons (sizeof (struct GNUNET_MessageHeader) +
471 sizeof (GNUNET_HashCode) + ntohs (udp->len));
472 hdr->type = ntohs (GNUNET_MESSAGE_TYPE_SERVICE_UDP);
473 GNUNET_assert (size >= ntohs (hdr->size));
474 memcpy (buf, hdr, ntohs (hdr->size));
475 size = ntohs(hdr->size);
477 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sent!\n");
482 port_in_ports (uint64_t ports, uint16_t port)
484 uint16_t *ps = (uint16_t *) & ports;
485 return ps[0] == port || ps[1] == port || ps[2] == port || ps[3] == port;
489 send_udp (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
491 struct GNUNET_PeerIdentity *peer = cls;
492 struct GNUNET_MessageHeader *hdr =
493 (struct GNUNET_MessageHeader *) (peer + 1);
494 GNUNET_HashCode *hc = (GNUNET_HashCode *) (hdr + 1);
495 struct udp_pkt *udp = (struct udp_pkt *) (hc + 1);
496 GNUNET_CORE_notify_transmit_ready (core_handle,
498 GNUNET_TIME_UNIT_FOREVER_REL,
501 (struct GNUNET_MessageHeader) +
502 sizeof (GNUNET_HashCode) +
503 ntohs (udp->len)), handle_udp,
508 * Receive packets from the helper-process
511 message_token(void *cls,
513 const struct GNUNET_MessageHeader *message) {
514 GNUNET_assert(ntohs(message->type) == GNUNET_MESSAGE_TYPE_VPN_HELPER);
516 struct tun_pkt *pkt_tun = (struct tun_pkt*) message;
518 /* ethertype is ipv6 */
519 if (ntohs(pkt_tun->tun.type) == 0x86dd)
521 struct ip6_pkt *pkt6 = (struct ip6_pkt*) message;
522 GNUNET_assert(pkt6->ip6_hdr.version == 6);
523 struct ip6_tcp *pkt6_tcp;
524 struct ip6_udp *pkt6_udp;
525 struct ip6_icmp *pkt6_icmp;
526 GNUNET_HashCode* key;
529 switch(pkt6->ip6_hdr.nxthdr)
532 pkt6_tcp = (struct ip6_tcp*)pkt6;
533 pkt_printf_ip6tcp(pkt6_tcp);
536 pkt6_udp = (struct ip6_udp*)pkt6;
537 if ((key = address_mapping_exists(pkt6->ip6_hdr.dadr)) != NULL)
539 struct map_entry* me = GNUNET_CONTAINER_multihashmap_get(hashmap, key);
540 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Mapping exists; type: %d; UDP is %d; port: %x/%x!\n", me->desc.service_type, htonl(GNUNET_DNS_SERVICE_TYPE_UDP), pkt6_udp->udp_hdr.dpt, me->desc.ports);
542 if (me->desc.service_type & htonl(GNUNET_DNS_SERVICE_TYPE_UDP) &&
543 (port_in_ports(me->desc.ports, pkt6_udp->udp_hdr.dpt) ||
544 port_in_ports(me->additional_ports, pkt6_udp->udp_hdr.dpt)))
546 size_t size = sizeof(struct GNUNET_PeerIdentity) + sizeof(struct GNUNET_MessageHeader) + sizeof(GNUNET_HashCode) + ntohs(pkt6_udp->udp_hdr.len);
547 struct GNUNET_PeerIdentity *cls = GNUNET_malloc(size);
548 struct GNUNET_MessageHeader *hdr = (struct GNUNET_MessageHeader*)(cls+1);
549 GNUNET_HashCode* hc = (GNUNET_HashCode*)(hdr + 1);
550 memcpy(cls, &me->desc.peer, sizeof(struct GNUNET_PeerIdentity));
551 memcpy(hc, &me->desc.service_descriptor, sizeof(GNUNET_HashCode));
552 memcpy(hc+1, &pkt6_udp->udp_hdr, ntohs(pkt6_udp->udp_hdr.len));
553 GNUNET_CORE_peer_request_connect(core_handle,
554 GNUNET_TIME_UNIT_FOREVER_REL,
555 (struct GNUNET_PeerIdentity*)&me->desc.peer,
558 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Queued to send to peer %x\n", *((unsigned int*)&me->desc.peer));
564 pkt6_icmp = (struct ip6_icmp*)pkt6;
565 /* If this packet is an icmp-echo-request and a mapping exists, answer */
566 if (pkt6_icmp->icmp_hdr.type == 0x80 && (key = address_mapping_exists(pkt6->ip6_hdr.dadr)) != NULL)
569 pkt6_icmp = GNUNET_malloc(ntohs(pkt6->shdr.size));
570 memcpy(pkt6_icmp, pkt6, ntohs(pkt6->shdr.size));
571 GNUNET_SCHEDULER_add_now(&send_icmp_response, pkt6_icmp);
576 /* ethertype is ipv4 */
577 else if (ntohs(pkt_tun->tun.type) == 0x0800)
579 struct ip_pkt *pkt = (struct ip_pkt*) message;
580 struct ip_udp *udp = (struct ip_udp*) message;
581 GNUNET_assert(pkt->ip_hdr.version == 4);
583 /* Send dns-packets to the service-dns */
584 if (pkt->ip_hdr.proto == 0x11 && ntohs(udp->udp_hdr.dpt) == 53 )
586 /* 9 = 8 for the udp-header + 1 for the unsigned char data[1]; */
587 size_t len = sizeof(struct query_packet) + ntohs(udp->udp_hdr.len) - 9;
589 struct query_packet_list* query = GNUNET_malloc(len + 2*sizeof(struct query_packet_list*));
590 query->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS);
591 query->pkt.hdr.size = htons(len);
592 query->pkt.orig_to = pkt->ip_hdr.dadr;
593 query->pkt.orig_from = pkt->ip_hdr.sadr;
594 query->pkt.src_port = udp->udp_hdr.spt;
595 memcpy(query->pkt.data, udp->data, ntohs(udp->udp_hdr.len) - 8);
597 GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, query);
599 if (dns_connection != NULL)
600 GNUNET_CLIENT_notify_transmit_ready(dns_connection,
602 GNUNET_TIME_UNIT_FOREVER_REL,
611 * Connect to the service-dns
614 connect_to_service_dns (void *cls,
615 const struct GNUNET_SCHEDULER_TaskContext *tc) {
616 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
618 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connecting to service-dns\n");
619 GNUNET_assert (dns_connection == NULL);
620 dns_connection = GNUNET_CLIENT_connect ("dns", cfg);
621 GNUNET_CLIENT_receive(dns_connection, &dns_answer_handler, NULL, GNUNET_TIME_UNIT_FOREVER_REL);
623 /* If a packet is already in the list, schedule to send it */
625 GNUNET_CLIENT_notify_transmit_ready(dns_connection,
626 ntohs(head->pkt.hdr.size),
627 GNUNET_TIME_UNIT_FOREVER_REL,
631 else if (restart_hijack == 1)
633 GNUNET_CLIENT_notify_transmit_ready(dns_connection, sizeof(struct GNUNET_MessageHeader), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
638 * Create a new Address from an answer-packet
642 new_ip6addr(char* buf, const GNUNET_HashCode *peer, const GNUNET_HashCode *service_desc) {
643 memcpy(buf+14, (int[]){htons(0x3412)}, 2);
644 memcpy(buf+8, service_desc, 6);
645 memcpy(buf, peer, 8);
650 * This gets scheduled with cls pointing to an answer_packet and does everything
651 * needed in order to send it to the helper.
653 * At the moment this means "inventing" and IPv6-Address for .gnunet-services and
654 * doing nothing for "real" services.
657 process_answer(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tc) {
658 struct answer_packet* pkt = cls;
659 struct answer_packet_list* list;
661 /* This answer is about a .gnunet-service
663 * It contains an almost complete DNS-Response, we have to fill in the ip
664 * at the offset pkt->addroffset
667 if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_SERVICE)
669 pkt->subtype = GNUNET_DNS_ANSWER_TYPE_IP;
672 memset(&key, 0, sizeof(GNUNET_HashCode));
673 new_ip6addr((char*)&key, &pkt->service_descr.peer, &pkt->service_descr.service_descriptor);
675 uint16_t namelen = strlen((char*)pkt->data+12)+1;
677 struct map_entry* value = GNUNET_malloc(sizeof(struct GNUNET_vpn_service_descriptor) + 2 + 8 + namelen);
679 value->namelen = namelen;
680 memcpy(value->name, pkt->data+12, namelen);
682 memcpy(&value->desc, &pkt->service_descr, sizeof(struct GNUNET_vpn_service_descriptor));
684 value->additional_ports = 0;
686 if (GNUNET_OK != GNUNET_CONTAINER_multihashmap_put(hashmap,
689 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
691 GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Could not store to hashmap\n");
695 * Copy the newly generated backward ip-address to the packet
697 char* c = ((char*)pkt)+ntohs(pkt->addroffset);
698 char* k = (char*)&key;
700 for (i = 0; i < 16; i++)
703 list = GNUNET_malloc(htons(pkt->hdr.size) + 2*sizeof(struct answer_packet_list*));
705 memcpy(&list->pkt, pkt, htons(pkt->hdr.size));
708 else if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_REV)
711 memset(&key, 0, sizeof key);
712 unsigned char* k = (unsigned char*)&key;
713 unsigned char* s = pkt->data+12;
715 /* Whoever designed the reverse IPv6-lookup is batshit insane */
716 for (i = 0; i < 16; i++)
718 unsigned char c1 = s[(4*i)+1];
719 unsigned char c2 = s[(4*i)+3];
723 k[i] = c1 - 87; /* 87 is the difference between 'a' and 10 */
725 k[i] += 16*(c2 - '0');
727 k[i] += 16*(c2 - 87);
730 struct map_entry* map_entry = GNUNET_CONTAINER_multihashmap_get(hashmap, &key);
731 unsigned short offset = ntohs(pkt->addroffset);
733 if (map_entry == NULL)
739 unsigned short namelen = htons(map_entry->namelen);
740 char* name = map_entry->name;
742 list = GNUNET_malloc(2*sizeof(struct answer_packet_list*) + offset + 2 + ntohs(namelen));
744 struct answer_packet* rpkt = &list->pkt;
746 memcpy(rpkt, pkt, offset);
748 rpkt->subtype = GNUNET_DNS_ANSWER_TYPE_IP;
749 rpkt->hdr.size = ntohs(offset + 2 + ntohs(namelen));
751 memcpy(((char*)rpkt)+offset, &namelen, 2);
752 memcpy(((char*)rpkt)+offset+2, name, ntohs(namelen));
755 else if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_IP)
757 list = GNUNET_malloc(htons(pkt->hdr.size) + 2*sizeof(struct answer_packet_list*));
758 memcpy(&list->pkt, pkt, htons(pkt->hdr.size));
769 GNUNET_CONTAINER_DLL_insert_after(answer_proc_head, answer_proc_tail, answer_proc_tail, list);
771 GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL, fh_to_helper, &helper_write, NULL);
777 * This receives packets from the service-dns and schedules process_answer to
781 dns_answer_handler(void* cls, const struct GNUNET_MessageHeader *msg) {
782 /* the service disconnected, reconnect after short wait */
785 GNUNET_CLIENT_disconnect(dns_connection, GNUNET_NO);
786 dns_connection = NULL;
787 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
788 &connect_to_service_dns,
793 /* the service did something strange, reconnect immediately */
794 if (msg->type != htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS))
797 GNUNET_CLIENT_disconnect(dns_connection, GNUNET_NO);
798 dns_connection = NULL;
799 GNUNET_SCHEDULER_add_now (&connect_to_service_dns,
803 void *pkt = GNUNET_malloc(ntohs(msg->size));
805 memcpy(pkt, msg, ntohs(msg->size));
807 GNUNET_SCHEDULER_add_now(process_answer, pkt);
808 GNUNET_CLIENT_receive(dns_connection, &dns_answer_handler, NULL, GNUNET_TIME_UNIT_FOREVER_REL);
813 struct GNUNET_PeerIdentity peer;
814 GNUNET_HashCode desc;
821 struct GNUNET_NETWORK_Handle *sock;
822 struct udp_state state;
826 send_udp_service (void *cls, size_t size, void *buf)
828 struct GNUNET_MessageHeader *hdr = cls;
829 GNUNET_assert(size >= ntohs(hdr->size));
831 memcpy(buf, cls, ntohs(hdr->size));
832 size_t ret = ntohs(hdr->size);
833 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sending %d bytes back!\n", ntohs(hdr->size));
839 receive_from_network (void *cls,
840 const struct GNUNET_SCHEDULER_TaskContext *tc)
842 if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
847 struct send_cls *data = cls;
851 struct sockaddr_in addr_in;
852 socklen_t addr_len = sizeof(struct sockaddr_in);
853 ssize_t len = GNUNET_NETWORK_socket_recvfrom (data->sock, buf, 1400, (struct sockaddr*)&addr_in, &addr_len);
856 GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Problem reading from socket: %m\n");
860 size_t len_udp = len + sizeof (struct udp_pkt);
861 size_t len_pkt = len_udp + sizeof (struct GNUNET_MessageHeader) + sizeof(GNUNET_HashCode);
862 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sending data back: data: %d; udp: %d, pkt:%d\n", len, len_udp, len_pkt);
864 struct GNUNET_MessageHeader *hdr = GNUNET_malloc (len_pkt);
865 GNUNET_HashCode *desc = (GNUNET_HashCode *) (hdr + 1);
866 struct udp_pkt *pkt = (struct udp_pkt *) (desc + 1);
868 hdr->size = htons (len_pkt);
869 hdr->type = htons (GNUNET_MESSAGE_TYPE_SERVICE_UDP_BACK);
871 pkt->dpt = htons(data->state.spt);
872 pkt->spt = addr_in.sin_port;
873 pkt->len = htons (len_udp);
874 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "UDP from %d to %d\n", ntohs(pkt->spt), ntohs(pkt->dpt));
875 /* The chksm can only be computed knowing the ip-addresses */
877 memcpy (desc, &data->state.desc, sizeof (GNUNET_HashCode));
878 memcpy (pkt + 1, buf, len);
880 GNUNET_CORE_notify_transmit_ready (core_handle, 42,
881 GNUNET_TIME_UNIT_FOREVER_REL,
882 &data->state.peer, len_pkt,
883 send_udp_service, hdr);
886 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, data->sock,
887 receive_from_network, cls);
891 send_to_network (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
893 if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
895 struct send_cls *data = cls;
896 struct udp_pkt *pkt = (struct udp_pkt *) (data + 1);
898 struct sockaddr_in a4;
899 memset(&a4, 0, sizeof(struct sockaddr_in));
900 a4.sin_family = AF_INET;
901 a4.sin_port = htons(data->state.dpt);
902 memcpy(&a4.sin_addr.s_addr, (char[]){127, 0, 0, 1}, 4);
904 GNUNET_NETWORK_socket_sendto (data->sock, pkt + 1,
905 ntohs (pkt->len) - sizeof (struct udp_pkt),
906 (struct sockaddr*)&a4, sizeof a4);
913 add_additional_port (struct map_entry *me, uint16_t port)
915 uint16_t *ps = (uint16_t *) & me->additional_ports;
917 for (i = 0; i < 4; i++)
928 receive_udp_back (void *cls, const struct GNUNET_PeerIdentity *other,
929 const struct GNUNET_MessageHeader *message,
930 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
932 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
933 struct udp_pkt *pkt = (struct udp_pkt *) (desc + 1);
935 new_ip6addr(addr, &other->hashPubKey, desc);
937 size_t size = sizeof(struct ip6_udp) + ntohs(pkt->len) - 1 - sizeof(struct udp_pkt);
939 struct ip6_udp* pkt6 = alloca(size);
941 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Relaying calc:%d gnu:%d udp:%d bytes!\n", size, ntohs(message->size), ntohs(pkt->len));
943 pkt6->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
944 pkt6->shdr.size = htons(size);
947 pkt6->tun.type = htons(0x86dd);
949 pkt6->ip6_hdr.version = 6;
950 pkt6->ip6_hdr.tclass_h = 0;
951 pkt6->ip6_hdr.tclass_l = 0;
952 pkt6->ip6_hdr.flowlbl = 0;
953 pkt6->ip6_hdr.paylgth = pkt->len;
954 pkt6->ip6_hdr.nxthdr = 0x11;
955 pkt6->ip6_hdr.hoplmt = 0xff;
958 for (i = 0; i < 16; i++)
959 pkt6->ip6_hdr.sadr[15-i] = addr[i];
961 memcpy(pkt6->ip6_hdr.dadr, (unsigned char[]){0x12, 0x34, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}, 16);
963 memcpy(&pkt6->udp_hdr, pkt, ntohs(pkt->len));
965 GNUNET_HashCode* key = address_mapping_exists(pkt6->ip6_hdr.sadr);
966 GNUNET_assert (key != NULL);
968 struct map_entry *me = GNUNET_CONTAINER_multihashmap_get(hashmap, key);
972 GNUNET_assert (me != NULL);
973 GNUNET_assert (me->desc.service_type & htonl(GNUNET_DNS_SERVICE_TYPE_UDP));
974 if (!port_in_ports(me->desc.ports, pkt6->udp_hdr.spt) ||
975 !port_in_ports(me->additional_ports, pkt6->udp_hdr.spt)) {
976 add_additional_port(me, pkt6->udp_hdr.spt);
979 pkt6->udp_hdr.crc = 0;
981 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->ip6_hdr.sadr, 16);
982 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->ip6_hdr.dadr, 16);
983 uint32_t tmp = (pkt6->udp_hdr.len & 0xffff);
984 sum = calculate_checksum_update(sum, (uint16_t*)&tmp, 4);
985 tmp = htons(((pkt6->ip6_hdr.nxthdr & 0x00ff)));
986 sum = calculate_checksum_update(sum, (uint16_t*)&tmp, 4);
988 sum = calculate_checksum_update(sum, (uint16_t*)&pkt6->udp_hdr, ntohs(pkt->len));
989 pkt6->udp_hdr.crc = calculate_checksum_end(sum);
992 /* FIXME */ GNUNET_DISK_file_write(fh_to_helper, pkt6, size);
998 receive_udp_service (void *cls, const struct GNUNET_PeerIdentity *other,
999 const struct GNUNET_MessageHeader *message,
1000 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
1002 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received UDP-Packet from peer %s\n",
1003 GNUNET_i2s (other));
1004 GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
1005 struct udp_pkt *pkt = (struct udp_pkt *) (desc + 1);
1007 /* FIXME -> check acl etc */
1008 GNUNET_assert (ntohs (pkt->len) ==
1009 ntohs (message->size) -
1010 sizeof (struct GNUNET_MessageHeader) -
1011 sizeof (GNUNET_HashCode));
1013 size_t state_size = sizeof (struct udp_state);
1014 size_t cls_size = sizeof (struct send_cls) + ntohs (pkt->len);
1015 struct send_cls *send = GNUNET_malloc (cls_size);
1016 struct udp_state *state = &send->state;
1017 unsigned int new = GNUNET_NO;
1019 memcpy (&state->peer, other, sizeof (struct GNUNET_PeerIdentity));
1020 memcpy (&state->desc, desc, sizeof (GNUNET_HashCode));
1021 state->spt = ntohs (pkt->spt);
1023 /* Hash without the dpt, so that eg tftp works */
1026 memcpy (send + 1, pkt, ntohs (pkt->len));
1028 GNUNET_HashCode hash;
1029 GNUNET_CRYPTO_hash (state, state_size, &hash);
1031 state->dpt = ntohs (pkt->dpt);
1033 struct GNUNET_NETWORK_Handle *sock =
1034 GNUNET_CONTAINER_multihashmap_get (udp_connections, &hash);
1038 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Creating new Socket!\n");
1039 sock = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
1045 GNUNET_CONTAINER_multihashmap_put (udp_connections, &hash, sock,
1046 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1051 struct send_cls *recv = GNUNET_malloc (sizeof (struct send_cls));
1052 memcpy (recv, send, sizeof (struct send_cls));
1053 GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, sock,
1054 receive_from_network, recv);
1057 GNUNET_SCHEDULER_add_write_net (GNUNET_TIME_UNIT_FOREVER_REL, sock,
1058 send_to_network, send);
1064 * Main function that will be run by the scheduler.
1066 * @param cls closure
1067 * @param args remaining command-line arguments
1068 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
1069 * @param cfg configuration
1074 const char *cfgfile,
1075 const struct GNUNET_CONFIGURATION_Handle *cfg_) {
1076 const static struct GNUNET_CORE_MessageHandler handlers[] = {
1077 {receive_udp_service, GNUNET_MESSAGE_TYPE_SERVICE_UDP, 0},
1078 {receive_udp_back, GNUNET_MESSAGE_TYPE_SERVICE_UDP_BACK, 0},
1081 core_handle = GNUNET_CORE_connect(cfg_,
1093 mst = GNUNET_SERVER_mst_create(&message_token, NULL);
1096 hashmap = GNUNET_CONTAINER_multihashmap_create(65536);
1097 udp_connections = GNUNET_CONTAINER_multihashmap_create(65536);
1098 GNUNET_SCHEDULER_add_now (connect_to_service_dns, NULL);
1099 GNUNET_SCHEDULER_add_now (start_helper_and_schedule, NULL);
1100 GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
1104 * The main function to obtain template from gnunetd.
1106 * @param argc number of arguments from the command line
1107 * @param argv command line arguments
1108 * @return 0 ok, 1 on error
1111 main (int argc, char *const *argv) {
1112 static const struct GNUNET_GETOPT_CommandLineOption options[] = {
1113 GNUNET_GETOPT_OPTION_END
1116 return (GNUNET_OK ==
1117 GNUNET_PROGRAM_run (argc,
1119 "gnunet-daemon-vpn",
1120 gettext_noop ("help text"),
1121 options, &run, NULL)) ? ret : 1;
1124 /* end of gnunet-daemon-vpn.c */