1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712
|
/*
* Implementation of the onion part of docs/Prevent_Tracking.txt
*/
/*
* Copyright © 2016-2018 The TokTok team.
* Copyright © 2013 Tox project.
*
* This file is part of Tox, the free peer to peer instant messenger.
*
* Tox is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Tox is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Tox. If not, see <http://www.gnu.org/licenses/>.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "onion.h"
#include <stdlib.h>
#include <string.h>
#include "mono_time.h"
#include "util.h"
#define RETURN_1 ONION_RETURN_1
#define RETURN_2 ONION_RETURN_2
#define RETURN_3 ONION_RETURN_3
#define SEND_BASE ONION_SEND_BASE
#define SEND_3 ONION_SEND_3
#define SEND_2 ONION_SEND_2
#define SEND_1 ONION_SEND_1
/* Change symmetric keys every 2 hours to make paths expire eventually. */
#define KEY_REFRESH_INTERVAL (2 * 60 * 60)
static void change_symmetric_key(Onion *onion)
{
if (mono_time_is_timeout(onion->mono_time, onion->timestamp, KEY_REFRESH_INTERVAL)) {
new_symmetric_key(onion->secret_symmetric_key);
onion->timestamp = mono_time_get(onion->mono_time);
}
}
/* packing and unpacking functions */
static void ip_pack(uint8_t *data, IP source)
{
data[0] = source.family.value;
if (net_family_is_ipv4(source.family) || net_family_is_tox_tcp_ipv4(source.family)) {
memset(data + 1, 0, SIZE_IP6);
memcpy(data + 1, source.ip.v4.uint8, SIZE_IP4);
} else {
memcpy(data + 1, source.ip.v6.uint8, SIZE_IP6);
}
}
/* return 0 on success, -1 on failure. */
static int ip_unpack(IP *target, const uint8_t *data, unsigned int data_size, bool disable_family_check)
{
if (data_size < (1 + SIZE_IP6)) {
return -1;
}
// TODO(iphydf): Validate input.
target->family.value = data[0];
if (net_family_is_ipv4(target->family) || net_family_is_tox_tcp_ipv4(target->family)) {
memcpy(target->ip.v4.uint8, data + 1, SIZE_IP4);
} else {
memcpy(target->ip.v6.uint8, data + 1, SIZE_IP6);
}
bool valid = disable_family_check ||
net_family_is_ipv4(target->family) ||
net_family_is_ipv6(target->family);
return valid ? 0 : -1;
}
static void ipport_pack(uint8_t *data, const IP_Port *source)
{
ip_pack(data, source->ip);
memcpy(data + SIZE_IP, &source->port, SIZE_PORT);
}
/* return 0 on success, -1 on failure. */
static int ipport_unpack(IP_Port *target, const uint8_t *data, unsigned int data_size, bool disable_family_check)
{
if (data_size < (SIZE_IP + SIZE_PORT)) {
return -1;
}
if (ip_unpack(&target->ip, data, data_size, disable_family_check) == -1) {
return -1;
}
memcpy(&target->port, data + SIZE_IP, SIZE_PORT);
return 0;
}
/* Create a new onion path.
*
* Create a new onion path out of nodes (nodes is a list of ONION_PATH_LENGTH nodes)
*
* new_path must be an empty memory location of at least Onion_Path size.
*
* return -1 on failure.
* return 0 on success.
*/
int create_onion_path(const DHT *dht, Onion_Path *new_path, const Node_format *nodes)
{
if (!new_path || !nodes) {
return -1;
}
encrypt_precompute(nodes[0].public_key, dht_get_self_secret_key(dht), new_path->shared_key1);
memcpy(new_path->public_key1, dht_get_self_public_key(dht), CRYPTO_PUBLIC_KEY_SIZE);
uint8_t random_public_key[CRYPTO_PUBLIC_KEY_SIZE];
uint8_t random_secret_key[CRYPTO_SECRET_KEY_SIZE];
crypto_new_keypair(random_public_key, random_secret_key);
encrypt_precompute(nodes[1].public_key, random_secret_key, new_path->shared_key2);
memcpy(new_path->public_key2, random_public_key, CRYPTO_PUBLIC_KEY_SIZE);
crypto_new_keypair(random_public_key, random_secret_key);
encrypt_precompute(nodes[2].public_key, random_secret_key, new_path->shared_key3);
memcpy(new_path->public_key3, random_public_key, CRYPTO_PUBLIC_KEY_SIZE);
new_path->ip_port1 = nodes[0].ip_port;
new_path->ip_port2 = nodes[1].ip_port;
new_path->ip_port3 = nodes[2].ip_port;
memcpy(new_path->node_public_key1, nodes[0].public_key, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(new_path->node_public_key2, nodes[1].public_key, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(new_path->node_public_key3, nodes[2].public_key, CRYPTO_PUBLIC_KEY_SIZE);
return 0;
}
/* Dump nodes in onion path to nodes of length num_nodes;
*
* return -1 on failure.
* return 0 on success.
*/
int onion_path_to_nodes(Node_format *nodes, unsigned int num_nodes, const Onion_Path *path)
{
if (num_nodes < ONION_PATH_LENGTH) {
return -1;
}
nodes[0].ip_port = path->ip_port1;
nodes[1].ip_port = path->ip_port2;
nodes[2].ip_port = path->ip_port3;
memcpy(nodes[0].public_key, path->node_public_key1, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(nodes[1].public_key, path->node_public_key2, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(nodes[2].public_key, path->node_public_key3, CRYPTO_PUBLIC_KEY_SIZE);
return 0;
}
/* Create a onion packet.
*
* Use Onion_Path path to create packet for data of length to dest.
* Maximum length of data is ONION_MAX_DATA_SIZE.
* packet should be at least ONION_MAX_PACKET_SIZE big.
*
* return -1 on failure.
* return length of created packet on success.
*/
int create_onion_packet(uint8_t *packet, uint16_t max_packet_length, const Onion_Path *path, IP_Port dest,
const uint8_t *data, uint16_t length)
{
if (1 + length + SEND_1 > max_packet_length || length == 0) {
return -1;
}
VLA(uint8_t, step1, SIZE_IPPORT + length);
ipport_pack(step1, &dest);
memcpy(step1 + SIZE_IPPORT, data, length);
uint8_t nonce[CRYPTO_NONCE_SIZE];
random_nonce(nonce);
VLA(uint8_t, step2, SIZE_IPPORT + SEND_BASE + length);
ipport_pack(step2, &path->ip_port3);
memcpy(step2 + SIZE_IPPORT, path->public_key3, CRYPTO_PUBLIC_KEY_SIZE);
int len = encrypt_data_symmetric(path->shared_key3, nonce, step1, SIZEOF_VLA(step1),
step2 + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + length + CRYPTO_MAC_SIZE) {
return -1;
}
VLA(uint8_t, step3, SIZE_IPPORT + SEND_BASE * 2 + length);
ipport_pack(step3, &path->ip_port2);
memcpy(step3 + SIZE_IPPORT, path->public_key2, CRYPTO_PUBLIC_KEY_SIZE);
len = encrypt_data_symmetric(path->shared_key2, nonce, step2, SIZEOF_VLA(step2),
step3 + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + SEND_BASE + length + CRYPTO_MAC_SIZE) {
return -1;
}
packet[0] = NET_PACKET_ONION_SEND_INITIAL;
memcpy(packet + 1, nonce, CRYPTO_NONCE_SIZE);
memcpy(packet + 1 + CRYPTO_NONCE_SIZE, path->public_key1, CRYPTO_PUBLIC_KEY_SIZE);
len = encrypt_data_symmetric(path->shared_key1, nonce, step3, SIZEOF_VLA(step3),
packet + 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + SEND_BASE * 2 + length + CRYPTO_MAC_SIZE) {
return -1;
}
return 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + len;
}
/* Create a onion packet to be sent over tcp.
*
* Use Onion_Path path to create packet for data of length to dest.
* Maximum length of data is ONION_MAX_DATA_SIZE.
* packet should be at least ONION_MAX_PACKET_SIZE big.
*
* return -1 on failure.
* return length of created packet on success.
*/
int create_onion_packet_tcp(uint8_t *packet, uint16_t max_packet_length, const Onion_Path *path, IP_Port dest,
const uint8_t *data, uint16_t length)
{
if (CRYPTO_NONCE_SIZE + SIZE_IPPORT + SEND_BASE * 2 + length > max_packet_length || length == 0) {
return -1;
}
VLA(uint8_t, step1, SIZE_IPPORT + length);
ipport_pack(step1, &dest);
memcpy(step1 + SIZE_IPPORT, data, length);
uint8_t nonce[CRYPTO_NONCE_SIZE];
random_nonce(nonce);
VLA(uint8_t, step2, SIZE_IPPORT + SEND_BASE + length);
ipport_pack(step2, &path->ip_port3);
memcpy(step2 + SIZE_IPPORT, path->public_key3, CRYPTO_PUBLIC_KEY_SIZE);
int len = encrypt_data_symmetric(path->shared_key3, nonce, step1, SIZEOF_VLA(step1),
step2 + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + length + CRYPTO_MAC_SIZE) {
return -1;
}
ipport_pack(packet + CRYPTO_NONCE_SIZE, &path->ip_port2);
memcpy(packet + CRYPTO_NONCE_SIZE + SIZE_IPPORT, path->public_key2, CRYPTO_PUBLIC_KEY_SIZE);
len = encrypt_data_symmetric(path->shared_key2, nonce, step2, SIZEOF_VLA(step2),
packet + CRYPTO_NONCE_SIZE + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + SEND_BASE + length + CRYPTO_MAC_SIZE) {
return -1;
}
memcpy(packet, nonce, CRYPTO_NONCE_SIZE);
return CRYPTO_NONCE_SIZE + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE + len;
}
/* Create and send a onion packet.
*
* Use Onion_Path path to send data of length to dest.
* Maximum length of data is ONION_MAX_DATA_SIZE.
*
* return -1 on failure.
* return 0 on success.
*/
int send_onion_packet(Networking_Core *net, const Onion_Path *path, IP_Port dest, const uint8_t *data, uint16_t length)
{
uint8_t packet[ONION_MAX_PACKET_SIZE];
int len = create_onion_packet(packet, sizeof(packet), path, dest, data, length);
if (len == -1) {
return -1;
}
if (sendpacket(net, path->ip_port1, packet, len) != len) {
return -1;
}
return 0;
}
/* Create and send a onion response sent initially to dest with.
* Maximum length of data is ONION_RESPONSE_MAX_DATA_SIZE.
*
* return -1 on failure.
* return 0 on success.
*/
int send_onion_response(Networking_Core *net, IP_Port dest, const uint8_t *data, uint16_t length, const uint8_t *ret)
{
if (length > ONION_RESPONSE_MAX_DATA_SIZE || length == 0) {
return -1;
}
VLA(uint8_t, packet, 1 + RETURN_3 + length);
packet[0] = NET_PACKET_ONION_RECV_3;
memcpy(packet + 1, ret, RETURN_3);
memcpy(packet + 1 + RETURN_3, data, length);
if ((uint32_t)sendpacket(net, dest, packet, SIZEOF_VLA(packet)) != SIZEOF_VLA(packet)) {
return -1;
}
return 0;
}
static int handle_send_initial(void *object, IP_Port source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + SEND_1) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[ONION_MAX_PACKET_SIZE];
uint8_t shared_key[CRYPTO_SHARED_KEY_SIZE];
get_shared_key(onion->mono_time, &onion->shared_keys_1, shared_key, dht_get_self_secret_key(onion->dht),
packet + 1 + CRYPTO_NONCE_SIZE);
int len = decrypt_data_symmetric(shared_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE,
length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE), plain);
if (len != length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + CRYPTO_MAC_SIZE)) {
return 1;
}
return onion_send_1(onion, plain, len, source, packet + 1);
}
int onion_send_1(const Onion *onion, const uint8_t *plain, uint16_t len, IP_Port source, const uint8_t *nonce)
{
if (len > ONION_MAX_PACKET_SIZE + SIZE_IPPORT - (1 + CRYPTO_NONCE_SIZE + ONION_RETURN_1)) {
return 1;
}
if (len <= SIZE_IPPORT + SEND_BASE * 2) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, 0) == -1) {
return 1;
}
uint8_t ip_port[SIZE_IPPORT];
ipport_pack(ip_port, &source);
uint8_t data[ONION_MAX_PACKET_SIZE];
data[0] = NET_PACKET_ONION_SEND_1;
memcpy(data + 1, nonce, CRYPTO_NONCE_SIZE);
memcpy(data + 1 + CRYPTO_NONCE_SIZE, plain + SIZE_IPPORT, len - SIZE_IPPORT);
uint16_t data_len = 1 + CRYPTO_NONCE_SIZE + (len - SIZE_IPPORT);
uint8_t *ret_part = data + data_len;
random_nonce(ret_part);
len = encrypt_data_symmetric(onion->secret_symmetric_key, ret_part, ip_port, SIZE_IPPORT,
ret_part + CRYPTO_NONCE_SIZE);
if (len != SIZE_IPPORT + CRYPTO_MAC_SIZE) {
return 1;
}
data_len += CRYPTO_NONCE_SIZE + len;
if ((uint32_t)sendpacket(onion->net, send_to, data, data_len) != data_len) {
return 1;
}
return 0;
}
static int handle_send_1(void *object, IP_Port source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + SEND_2) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[ONION_MAX_PACKET_SIZE];
uint8_t shared_key[CRYPTO_SHARED_KEY_SIZE];
get_shared_key(onion->mono_time, &onion->shared_keys_2, shared_key, dht_get_self_secret_key(onion->dht),
packet + 1 + CRYPTO_NONCE_SIZE);
int len = decrypt_data_symmetric(shared_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE,
length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + RETURN_1), plain);
if (len != length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + RETURN_1 + CRYPTO_MAC_SIZE)) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, 0) == -1) {
return 1;
}
uint8_t data[ONION_MAX_PACKET_SIZE];
data[0] = NET_PACKET_ONION_SEND_2;
memcpy(data + 1, packet + 1, CRYPTO_NONCE_SIZE);
memcpy(data + 1 + CRYPTO_NONCE_SIZE, plain + SIZE_IPPORT, len - SIZE_IPPORT);
uint16_t data_len = 1 + CRYPTO_NONCE_SIZE + (len - SIZE_IPPORT);
uint8_t *ret_part = data + data_len;
random_nonce(ret_part);
uint8_t ret_data[RETURN_1 + SIZE_IPPORT];
ipport_pack(ret_data, &source);
memcpy(ret_data + SIZE_IPPORT, packet + (length - RETURN_1), RETURN_1);
len = encrypt_data_symmetric(onion->secret_symmetric_key, ret_part, ret_data, sizeof(ret_data),
ret_part + CRYPTO_NONCE_SIZE);
if (len != RETURN_2 - CRYPTO_NONCE_SIZE) {
return 1;
}
data_len += CRYPTO_NONCE_SIZE + len;
if ((uint32_t)sendpacket(onion->net, send_to, data, data_len) != data_len) {
return 1;
}
return 0;
}
static int handle_send_2(void *object, IP_Port source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + SEND_3) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[ONION_MAX_PACKET_SIZE];
uint8_t shared_key[CRYPTO_SHARED_KEY_SIZE];
get_shared_key(onion->mono_time, &onion->shared_keys_3, shared_key, dht_get_self_secret_key(onion->dht),
packet + 1 + CRYPTO_NONCE_SIZE);
int len = decrypt_data_symmetric(shared_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE,
length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + RETURN_2), plain);
if (len != length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + RETURN_2 + CRYPTO_MAC_SIZE)) {
return 1;
}
if (len <= SIZE_IPPORT) {
return 1;
}
if (plain[SIZE_IPPORT] != NET_PACKET_ANNOUNCE_REQUEST &&
plain[SIZE_IPPORT] != NET_PACKET_ONION_DATA_REQUEST) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, 0) == -1) {
return 1;
}
uint8_t data[ONION_MAX_PACKET_SIZE];
memcpy(data, plain + SIZE_IPPORT, len - SIZE_IPPORT);
uint16_t data_len = (len - SIZE_IPPORT);
uint8_t *ret_part = data + (len - SIZE_IPPORT);
random_nonce(ret_part);
uint8_t ret_data[RETURN_2 + SIZE_IPPORT];
ipport_pack(ret_data, &source);
memcpy(ret_data + SIZE_IPPORT, packet + (length - RETURN_2), RETURN_2);
len = encrypt_data_symmetric(onion->secret_symmetric_key, ret_part, ret_data, sizeof(ret_data),
ret_part + CRYPTO_NONCE_SIZE);
if (len != RETURN_3 - CRYPTO_NONCE_SIZE) {
return 1;
}
data_len += RETURN_3;
if ((uint32_t)sendpacket(onion->net, send_to, data, data_len) != data_len) {
return 1;
}
return 0;
}
static int handle_recv_3(void *object, IP_Port source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + RETURN_3) {
return 1;
}
if (packet[1 + RETURN_3] != NET_PACKET_ANNOUNCE_RESPONSE &&
packet[1 + RETURN_3] != NET_PACKET_ONION_DATA_RESPONSE) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[SIZE_IPPORT + RETURN_2];
int len = decrypt_data_symmetric(onion->secret_symmetric_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE,
SIZE_IPPORT + RETURN_2 + CRYPTO_MAC_SIZE, plain);
if ((uint32_t)len != sizeof(plain)) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, 0) == -1) {
return 1;
}
uint8_t data[ONION_MAX_PACKET_SIZE];
data[0] = NET_PACKET_ONION_RECV_2;
memcpy(data + 1, plain + SIZE_IPPORT, RETURN_2);
memcpy(data + 1 + RETURN_2, packet + 1 + RETURN_3, length - (1 + RETURN_3));
uint16_t data_len = 1 + RETURN_2 + (length - (1 + RETURN_3));
if ((uint32_t)sendpacket(onion->net, send_to, data, data_len) != data_len) {
return 1;
}
return 0;
}
static int handle_recv_2(void *object, IP_Port source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + RETURN_2) {
return 1;
}
if (packet[1 + RETURN_2] != NET_PACKET_ANNOUNCE_RESPONSE &&
packet[1 + RETURN_2] != NET_PACKET_ONION_DATA_RESPONSE) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[SIZE_IPPORT + RETURN_1];
int len = decrypt_data_symmetric(onion->secret_symmetric_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE,
SIZE_IPPORT + RETURN_1 + CRYPTO_MAC_SIZE, plain);
if ((uint32_t)len != sizeof(plain)) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, 0) == -1) {
return 1;
}
uint8_t data[ONION_MAX_PACKET_SIZE];
data[0] = NET_PACKET_ONION_RECV_1;
memcpy(data + 1, plain + SIZE_IPPORT, RETURN_1);
memcpy(data + 1 + RETURN_1, packet + 1 + RETURN_2, length - (1 + RETURN_2));
uint16_t data_len = 1 + RETURN_1 + (length - (1 + RETURN_2));
if ((uint32_t)sendpacket(onion->net, send_to, data, data_len) != data_len) {
return 1;
}
return 0;
}
static int handle_recv_1(void *object, IP_Port source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + RETURN_1) {
return 1;
}
if (packet[1 + RETURN_1] != NET_PACKET_ANNOUNCE_RESPONSE &&
packet[1 + RETURN_1] != NET_PACKET_ONION_DATA_RESPONSE) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[SIZE_IPPORT];
int len = decrypt_data_symmetric(onion->secret_symmetric_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE,
SIZE_IPPORT + CRYPTO_MAC_SIZE, plain);
if ((uint32_t)len != SIZE_IPPORT) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, 1) == -1) {
return 1;
}
uint16_t data_len = length - (1 + RETURN_1);
if (onion->recv_1_function &&
!net_family_is_ipv4(send_to.ip.family) &&
!net_family_is_ipv6(send_to.ip.family)) {
return onion->recv_1_function(onion->callback_object, send_to, packet + (1 + RETURN_1), data_len);
}
if ((uint32_t)sendpacket(onion->net, send_to, packet + (1 + RETURN_1), data_len) != data_len) {
return 1;
}
return 0;
}
void set_callback_handle_recv_1(Onion *onion, onion_recv_1_cb *function, void *object)
{
onion->recv_1_function = function;
onion->callback_object = object;
}
Onion *new_onion(Mono_Time *mono_time, DHT *dht)
{
if (dht == nullptr) {
return nullptr;
}
Onion *onion = (Onion *)calloc(1, sizeof(Onion));
if (onion == nullptr) {
return nullptr;
}
onion->dht = dht;
onion->net = dht_get_net(dht);
onion->mono_time = mono_time;
new_symmetric_key(onion->secret_symmetric_key);
onion->timestamp = mono_time_get(onion->mono_time);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_INITIAL, &handle_send_initial, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_1, &handle_send_1, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_2, &handle_send_2, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_3, &handle_recv_3, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_2, &handle_recv_2, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_1, &handle_recv_1, onion);
return onion;
}
void kill_onion(Onion *onion)
{
if (onion == nullptr) {
return;
}
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_INITIAL, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_1, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_2, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_3, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_2, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_1, nullptr, nullptr);
free(onion);
}
|