toxcore/toxcore/onion.h

136 lines
4.6 KiB
C

/*
* onion.h -- Implementation of the onion part of docs/Prevent_Tracking.txt
*
* Copyright (C) 2013 Tox project All Rights Reserved.
*
* This file is part of Tox.
*
* 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/>.
*
*/
#ifndef ONION_H
#define ONION_H
#include "DHT.h"
typedef struct {
DHT *dht;
Networking_Core *net;
uint8_t secret_symmetric_key[crypto_box_KEYBYTES];
uint64_t timestamp;
Shared_Keys shared_keys_1;
Shared_Keys shared_keys_2;
Shared_Keys shared_keys_3;
int (*recv_1_function)(void *, IP_Port, const uint8_t *, uint16_t);
void *callback_object;
} Onion;
#define ONION_MAX_PACKET_SIZE 1400
#define ONION_RETURN_1 (crypto_box_NONCEBYTES + SIZE_IPPORT + crypto_box_MACBYTES)
#define ONION_RETURN_2 (crypto_box_NONCEBYTES + SIZE_IPPORT + crypto_box_MACBYTES + ONION_RETURN_1)
#define ONION_RETURN_3 (crypto_box_NONCEBYTES + SIZE_IPPORT + crypto_box_MACBYTES + ONION_RETURN_2)
#define ONION_SEND_BASE (crypto_box_PUBLICKEYBYTES + SIZE_IPPORT + crypto_box_MACBYTES)
#define ONION_SEND_3 (crypto_box_NONCEBYTES + ONION_SEND_BASE + ONION_RETURN_2)
#define ONION_SEND_2 (crypto_box_NONCEBYTES + ONION_SEND_BASE*2 + ONION_RETURN_1)
#define ONION_SEND_1 (crypto_box_NONCEBYTES + ONION_SEND_BASE*3)
#define ONION_MAX_DATA_SIZE (ONION_MAX_PACKET_SIZE - (ONION_SEND_1 + 1))
#define ONION_RESPONSE_MAX_DATA_SIZE (ONION_MAX_PACKET_SIZE - (1 + ONION_RETURN_3))
typedef struct {
uint8_t shared_key1[crypto_box_BEFORENMBYTES];
uint8_t shared_key2[crypto_box_BEFORENMBYTES];
uint8_t shared_key3[crypto_box_BEFORENMBYTES];
uint8_t public_key1[crypto_box_PUBLICKEYBYTES];
uint8_t public_key2[crypto_box_PUBLICKEYBYTES];
uint8_t public_key3[crypto_box_PUBLICKEYBYTES];
IP_Port ip_port1;
IP_Port ip_port2;
IP_Port ip_port3;
} Onion_Path;
/* Create a new onion path.
*
* Create a new onion path out of nodes (nodes is a list of 3 nodes)
*
* new_path must be an empty memory location of atleast 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);
/* 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, uint32_t length);
/* 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, uint32_t length);
/* 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, uint32_t length, const uint8_t *ret);
/* Function to handle/send received decrypted versions of the packet sent with send_onion_packet.
*
* return 0 on success.
* return 1 on failure.
*
* Used to handle these packets that are received in a non traditional way (by TCP for example).
*
* Source family must be set to something else than AF_INET6 or AF_INET so that the callback gets called
* when the response is received.
*/
int onion_send_1(const Onion *onion, const uint8_t *plain, uint32_t len, IP_Port source, const uint8_t *nonce);
/* Set the callback to be called when the dest ip_port doesn't have AF_INET6 or AF_INET as the family.
*
* Format: function(void *object, IP_Port dest, uint8_t *data, uint32_t length)
*/
void set_callback_handle_recv_1(Onion *onion, int (*function)(void *, IP_Port, const uint8_t *, uint16_t),
void *object);
Onion *new_onion(DHT *dht);
void kill_onion(Onion *onion);
#endif