toxcore/toxcore/TCP_connection.c
2015-06-28 22:51:27 -04:00

1366 lines
38 KiB
C

/* TCP_connection.c
*
* Handles TCP relay connections between two Tox clients.
*
* Copyright (C) 2015 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/>.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "TCP_connection.h"
#include "util.h"
/* Set the size of the array to num.
*
* return -1 if realloc fails.
* return 0 if it succeeds.
*/
#define realloc_tox_array(array, element_size, num, temp_pointer) (num ? (temp_pointer = realloc(array, ((num) * (element_size))), temp_pointer ? (array = temp_pointer, 0) : (-1) ) : (free(array), array = NULL, 0))
/* return 1 if the connections_number is not valid.
* return 0 if the connections_number is valid.
*/
static _Bool connections_number_not_valid(const TCP_Connections *tcp_c, int connections_number)
{
if ((unsigned int)connections_number >= tcp_c->connections_length)
return 1;
if (tcp_c->connections == NULL)
return 1;
if (tcp_c->connections[connections_number].status == TCP_CONN_NONE)
return 1;
return 0;
}
/* return 1 if the tcp_connections_number is not valid.
* return 0 if the tcp_connections_number is valid.
*/
static _Bool tcp_connections_number_not_valid(const TCP_Connections *tcp_c, int tcp_connections_number)
{
if ((unsigned int)tcp_connections_number >= tcp_c->tcp_connections_length)
return 1;
if (tcp_c->tcp_connections == NULL)
return 1;
if (tcp_c->tcp_connections[tcp_connections_number].status == TCP_CONN_NONE)
return 1;
return 0;
}
/* Create a new empty connection.
*
* return -1 on failure.
* return connections_number on success.
*/
static int create_connection(TCP_Connections *tcp_c)
{
uint32_t i;
for (i = 0; i < tcp_c->connections_length; ++i) {
if (tcp_c->connections[i].status == TCP_CONN_NONE)
return i;
}
int id = -1;
TCP_Connection_to *temp_pointer;
if (realloc_tox_array(tcp_c->connections, sizeof(TCP_Connection_to), tcp_c->connections_length + 1,
temp_pointer) == 0) {
id = tcp_c->connections_length;
++tcp_c->connections_length;
memset(&(tcp_c->connections[id]), 0, sizeof(TCP_Connection_to));
}
return id;
}
/* Create a new empty tcp connection.
*
* return -1 on failure.
* return tcp_connections_number on success.
*/
static int create_tcp_connection(TCP_Connections *tcp_c)
{
uint32_t i;
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
if (tcp_c->tcp_connections[i].status == TCP_CONN_NONE)
return i;
}
int id = -1;
TCP_con *temp_pointer;
if (realloc_tox_array(tcp_c->tcp_connections, sizeof(TCP_con), tcp_c->tcp_connections_length + 1, temp_pointer) == 0) {
id = tcp_c->tcp_connections_length;
++tcp_c->tcp_connections_length;
memset(&(tcp_c->tcp_connections[id]), 0, sizeof(TCP_con));
}
return id;
}
/* Wipe a connection.
*
* return -1 on failure.
* return 0 on success.
*/
static int wipe_connection(TCP_Connections *tcp_c, int connections_number)
{
if (connections_number_not_valid(tcp_c, connections_number))
return -1;
uint32_t i;
memset(&(tcp_c->connections[connections_number]), 0 , sizeof(TCP_Connection_to));
for (i = tcp_c->connections_length; i != 0; --i) {
if (tcp_c->connections[i - 1].status != TCP_CONN_NONE)
break;
}
if (tcp_c->connections_length != i) {
tcp_c->connections_length = i;
TCP_Connection_to *temp_pointer;
realloc_tox_array(tcp_c->connections, sizeof(TCP_Connection_to), tcp_c->connections_length, temp_pointer);
}
return 0;
}
/* Wipe a connection.
*
* return -1 on failure.
* return 0 on success.
*/
static int wipe_tcp_connection(TCP_Connections *tcp_c, int tcp_connections_number)
{
if (tcp_connections_number_not_valid(tcp_c, tcp_connections_number))
return -1;
uint32_t i;
memset(&(tcp_c->tcp_connections[tcp_connections_number]), 0 , sizeof(TCP_con));
for (i = tcp_c->tcp_connections_length; i != 0; --i) {
if (tcp_c->tcp_connections[i - 1].status != TCP_CONN_NONE)
break;
}
if (tcp_c->tcp_connections_length != i) {
tcp_c->tcp_connections_length = i;
TCP_con *temp_pointer;
realloc_tox_array(tcp_c->tcp_connections, sizeof(TCP_con), tcp_c->tcp_connections_length, temp_pointer);
}
return 0;
}
static TCP_Connection_to *get_connection(const TCP_Connections *tcp_c, int connections_number)
{
if (connections_number_not_valid(tcp_c, connections_number))
return 0;
return &tcp_c->connections[connections_number];
}
static TCP_con *get_tcp_connection(const TCP_Connections *tcp_c, int tcp_connections_number)
{
if (tcp_connections_number_not_valid(tcp_c, tcp_connections_number))
return 0;
return &tcp_c->tcp_connections[tcp_connections_number];
}
/* Send a packet to the TCP connection.
*
* return -1 on failure.
* return 0 on success.
*/
int send_packet_tcp_connection(TCP_Connections *tcp_c, int connections_number, const uint8_t *packet, uint16_t length)
{
TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
if (!con_to) {
return -1;
}
//TODO: detect and kill bad relays.
//TODO: thread safety?
unsigned int i;
int ret = -1;
_Bool limit_reached = 0;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
uint32_t tcp_con_num = con_to->connections[i].tcp_connection;
uint8_t status = con_to->connections[i].status;
uint8_t connection_id = con_to->connections[i].connection_id;
if (tcp_con_num && status == TCP_CONNECTIONS_STATUS_ONLINE) {
tcp_con_num -= 1;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_con_num);
if (!tcp_con) {
continue;
}
ret = send_data(tcp_con->connection, connection_id, packet, length);
if (ret == 0) {
limit_reached = 1;
}
if (ret == 1) {
break;
}
}
}
if (ret == 1) {
return 0;
} else if (!limit_reached) {
ret = 0;
/* Send oob packets to all relays tied to the connection. */
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
uint32_t tcp_con_num = con_to->connections[i].tcp_connection;
uint8_t status = con_to->connections[i].status;
if (tcp_con_num && status == TCP_CONNECTIONS_STATUS_REGISTERED) {
tcp_con_num -= 1;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_con_num);
if (!tcp_con) {
continue;
}
if (send_oob_packet(tcp_con->connection, con_to->public_key, packet, length) == 1) {
ret += 1;
}
}
}
if (ret >= 1) {
return 0;
} else {
return -1;
}
} else {
return -1;
}
}
/* Return a random TCP connection number for use in send_tcp_onion_request.
*
* TODO: This number is just the index of an array that the elements can
* change without warning.
*
* return TCP connection number on success.
* return -1 on failure.
*/
int get_random_tcp_onion_conn_number(TCP_Connections *tcp_c)
{
unsigned int i, r = rand();
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
unsigned int index = ((i + r) % tcp_c->tcp_connections_length);
if (tcp_c->tcp_connections[index].onion && tcp_c->tcp_connections[index].status == TCP_CONN_CONNECTED) {
return index;
}
}
return -1;
}
/* Send an onion packet via the TCP relay corresponding to tcp_connections_number.
*
* return 0 on success.
* return -1 on failure.
*/
int tcp_send_onion_request(TCP_Connections *tcp_c, unsigned int tcp_connections_number, const uint8_t *data,
uint16_t length)
{
if (tcp_connections_number >= tcp_c->tcp_connections_length) {
return -1;
}
if (tcp_c->tcp_connections[tcp_connections_number].status == TCP_CONN_CONNECTED) {
int ret = send_onion_request(tcp_c->tcp_connections[tcp_connections_number].connection, data, length);
if (ret == 1)
return 0;
}
return -1;
}
/* Send an oob packet via the TCP relay corresponding to tcp_connections_number.
*
* return 0 on success.
* return -1 on failure.
*/
int tcp_send_oob_packet(TCP_Connections *tcp_c, unsigned int tcp_connections_number, const uint8_t *public_key,
const uint8_t *packet, uint16_t length)
{
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
if (tcp_con->status != TCP_CONN_CONNECTED)
return -1;
int ret = send_oob_packet(tcp_con->connection, public_key, packet, length);
if (ret == 1)
return 0;
return -1;
}
/* Set the callback for TCP data packets.
*/
void set_packet_tcp_connection_callback(TCP_Connections *tcp_c, int (*tcp_data_callback)(void *object, int id,
const uint8_t *data, uint16_t length), void *object)
{
tcp_c->tcp_data_callback = tcp_data_callback;
tcp_c->tcp_data_callback_object = object;
}
/* Set the callback for TCP onion packets.
*/
void set_oob_packet_tcp_connection_callback(TCP_Connections *tcp_c, int (*tcp_oob_callback)(void *object,
const uint8_t *public_key, unsigned int tcp_connections_number, const uint8_t *data, uint16_t length), void *object)
{
tcp_c->tcp_oob_callback = tcp_oob_callback;
tcp_c->tcp_oob_callback_object = object;
}
/* Set the callback for TCP oob data packets.
*/
void set_onion_packet_tcp_connection_callback(TCP_Connections *tcp_c, int (*tcp_onion_callback)(void *object,
const uint8_t *data, uint16_t length), void *object)
{
tcp_c->tcp_onion_callback = tcp_onion_callback;
tcp_c->tcp_onion_callback_object = object;
}
/* Find the TCP connection with public_key.
*
* return connections_number on success.
* return -1 on failure.
*/
static int find_tcp_connection_to(TCP_Connections *tcp_c, const uint8_t *public_key)
{
unsigned int i;
for (i = 0; i < tcp_c->connections_length; ++i) {
TCP_Connection_to *con_to = get_connection(tcp_c, i);
if (con_to) {
if (memcmp(con_to->public_key, public_key, crypto_box_PUBLICKEYBYTES) == 0) {
return i;
}
}
}
return -1;
}
/* Find the TCP connection to a relay with relay_pk.
*
* return connections_number on success.
* return -1 on failure.
*/
static int find_tcp_connection_relay(TCP_Connections *tcp_c, const uint8_t *relay_pk)
{
unsigned int i;
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
TCP_con *tcp_con = get_tcp_connection(tcp_c, i);
if (tcp_con) {
if (tcp_con->status == TCP_CONN_SLEEPING) {
if (memcmp(tcp_con->relay_pk, relay_pk, crypto_box_PUBLICKEYBYTES) == 0) {
return i;
}
} else {
if (memcmp(tcp_con->connection->public_key, relay_pk, crypto_box_PUBLICKEYBYTES) == 0) {
return i;
}
}
}
}
return -1;
}
/* Create a new TCP connection to public_key.
*
* public_key must be the counterpart to the secret key that the other peer used with new_tcp_connections().
*
* id is the id in the callbacks for that connection.
*
* return connections_number on success.
* return -1 on failure.
*/
int new_tcp_connection_to(TCP_Connections *tcp_c, const uint8_t *public_key, int id)
{
if (find_tcp_connection_to(tcp_c, public_key) != -1)
return -1;
int connections_number = create_connection(tcp_c);
if (connections_number == -1)
return -1;
TCP_Connection_to *con_to = &tcp_c->connections[connections_number];
con_to->status = TCP_CONN_VALID;
memcpy(con_to->public_key, public_key, crypto_box_PUBLICKEYBYTES);
con_to->id = id;
return connections_number;
}
/* return 0 on success.
* return -1 on failure.
*/
int kill_tcp_connection_to(TCP_Connections *tcp_c, int connections_number)
{
TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
if (!con_to)
return -1;
unsigned int i;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
if (con_to->connections[i].tcp_connection) {
unsigned int tcp_connections_number = con_to->connections[i].tcp_connection - 1;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
continue;
if (tcp_con->status == TCP_CONN_CONNECTED) {
send_disconnect_request(tcp_con->connection, con_to->connections[i].connection_id);
}
if (con_to->connections[i].status == TCP_CONNECTIONS_STATUS_ONLINE) {
--tcp_con->lock_count;
if (con_to->status == TCP_CONN_SLEEPING) {
--tcp_con->sleep_count;
}
}
}
}
return wipe_connection(tcp_c, connections_number);
}
/* Set connection status.
*
* status of 1 means we are using the connection.
* status of 0 means we are not using it.
*
* Unused tcp connections will be disconnected from but kept in case they are needed.
*
* return 0 on success.
* return -1 on failure.
*/
int set_tcp_connection_to_status(TCP_Connections *tcp_c, int connections_number, _Bool status)
{
TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
if (!con_to)
return -1;
if (status) {
/* Conection is unsleeping. */
if (con_to->status != TCP_CONN_SLEEPING)
return -1;
unsigned int i;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
if (con_to->connections[i].tcp_connection) {
unsigned int tcp_connections_number = con_to->connections[i].tcp_connection - 1;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
continue;
if (tcp_con->status == TCP_CONN_SLEEPING) {
tcp_con->unsleep = 1;
}
}
}
con_to->status = TCP_CONN_VALID;
return 0;
} else {
/* Conection is going to sleep. */
if (con_to->status != TCP_CONN_VALID)
return -1;
unsigned int i;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
if (con_to->connections[i].tcp_connection) {
unsigned int tcp_connections_number = con_to->connections[i].tcp_connection - 1;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
continue;
if (con_to->connections[i].status == TCP_CONNECTIONS_STATUS_ONLINE) {
++tcp_con->sleep_count;
}
}
}
con_to->status = TCP_CONN_SLEEPING;
return 0;
}
}
static _Bool tcp_connection_in_conn(TCP_Connection_to *con_to, unsigned int tcp_connections_number)
{
unsigned int i;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
if (con_to->connections[i].tcp_connection == (tcp_connections_number + 1)) {
return 1;
}
}
return 0;
}
/* return index on success.
* return -1 on failure.
*/
static int add_tcp_connection_to_conn(TCP_Connection_to *con_to, unsigned int tcp_connections_number)
{
unsigned int i;
if (tcp_connection_in_conn(con_to, tcp_connections_number))
return -1;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
if (con_to->connections[i].tcp_connection == 0) {
con_to->connections[i].tcp_connection = tcp_connections_number + 1;
con_to->connections[i].status = TCP_CONNECTIONS_STATUS_NONE;
con_to->connections[i].connection_id = 0;
return i;
}
}
return -1;
}
/* return index on success.
* return -1 on failure.
*/
static int rm_tcp_connection_from_conn(TCP_Connection_to *con_to, unsigned int tcp_connections_number)
{
unsigned int i;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
if (con_to->connections[i].tcp_connection == (tcp_connections_number + 1)) {
con_to->connections[i].tcp_connection = 0;
con_to->connections[i].status = TCP_CONNECTIONS_STATUS_NONE;
con_to->connections[i].connection_id = 0;
return i;
}
}
return -1;
}
/* return number of online connections on success.
* return -1 on failure.
*/
static unsigned int online_tcp_connection_from_conn(TCP_Connection_to *con_to)
{
unsigned int i, count = 0;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
if (con_to->connections[i].tcp_connection) {
if (con_to->connections[i].status == TCP_CONNECTIONS_STATUS_ONLINE) {
++count;
}
}
}
return count;
}
/* return index on success.
* return -1 on failure.
*/
static int set_tcp_connection_status(TCP_Connection_to *con_to, unsigned int tcp_connections_number,
unsigned int status, uint8_t connection_id)
{
unsigned int i;
for (i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
if (con_to->connections[i].tcp_connection == (tcp_connections_number + 1)) {
if (con_to->connections[i].status == status) {
return -1;
}
con_to->connections[i].status = status;
con_to->connections[i].connection_id = connection_id;
return i;
}
}
return -1;
}
/* Kill a TCP relay connection.
*
* return 0 on success.
* return -1 on failure.
*/
static int kill_tcp_relay_connection(TCP_Connections *tcp_c, int tcp_connections_number)
{
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
unsigned int i;
for (i = 0; i < tcp_c->connections_length; ++i) {
TCP_Connection_to *con_to = get_connection(tcp_c, i);
if (con_to) {
rm_tcp_connection_from_conn(con_to, tcp_connections_number);
}
}
if (tcp_con->onion) {
--tcp_c->onion_num_conns;
}
kill_TCP_connection(tcp_con->connection);
return wipe_tcp_connection(tcp_c, tcp_connections_number);
}
static int reconnect_tcp_relay_connection(TCP_Connections *tcp_c, int tcp_connections_number)
{
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
if (tcp_con->status == TCP_CONN_SLEEPING)
return -1;
IP_Port ip_port = tcp_con->connection->ip_port;
uint8_t relay_pk[crypto_box_PUBLICKEYBYTES];
memcpy(relay_pk, tcp_con->connection->public_key, crypto_box_PUBLICKEYBYTES);
kill_TCP_connection(tcp_con->connection);
tcp_con->connection = new_TCP_connection(ip_port, relay_pk, tcp_c->self_public_key, tcp_c->self_secret_key,
&tcp_c->proxy_info);
if (!tcp_con->connection) {
kill_tcp_relay_connection(tcp_c, tcp_connections_number);
return -1;
}
unsigned int i;
for (i = 0; i < tcp_c->connections_length; ++i) {
TCP_Connection_to *con_to = get_connection(tcp_c, i);
if (con_to) {
set_tcp_connection_status(con_to, tcp_connections_number, TCP_CONNECTIONS_STATUS_NONE, 0);
}
}
if (tcp_con->onion) {
--tcp_c->onion_num_conns;
tcp_con->onion = 0;
}
tcp_con->lock_count = 0;
tcp_con->sleep_count = 0;
tcp_con->connected_time = 0;
tcp_con->status = TCP_CONN_VALID;
tcp_con->unsleep = 0;
return 0;
}
static int sleep_tcp_relay_connection(TCP_Connections *tcp_c, int tcp_connections_number)
{
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
if (tcp_con->status != TCP_CONN_CONNECTED)
return -1;
if (tcp_con->lock_count != tcp_con->sleep_count)
return -1;
tcp_con->ip_port = tcp_con->connection->ip_port;
memcpy(tcp_con->relay_pk, tcp_con->connection->public_key, crypto_box_PUBLICKEYBYTES);
kill_TCP_connection(tcp_con->connection);
tcp_con->connection = NULL;
unsigned int i;
for (i = 0; i < tcp_c->connections_length; ++i) {
TCP_Connection_to *con_to = get_connection(tcp_c, i);
if (con_to) {
set_tcp_connection_status(con_to, tcp_connections_number, TCP_CONNECTIONS_STATUS_NONE, 0);
}
}
if (tcp_con->onion) {
--tcp_c->onion_num_conns;
tcp_con->onion = 0;
}
tcp_con->lock_count = 0;
tcp_con->sleep_count = 0;
tcp_con->connected_time = 0;
tcp_con->status = TCP_CONN_SLEEPING;
tcp_con->unsleep = 0;
return 0;
}
static int unsleep_tcp_relay_connection(TCP_Connections *tcp_c, int tcp_connections_number)
{
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
if (tcp_con->status != TCP_CONN_SLEEPING)
return -1;
tcp_con->connection = new_TCP_connection(tcp_con->ip_port, tcp_con->relay_pk, tcp_c->self_public_key,
tcp_c->self_secret_key, &tcp_c->proxy_info);
if (!tcp_con->connection) {
kill_tcp_relay_connection(tcp_c, tcp_connections_number);
return -1;
}
tcp_con->lock_count = 0;
tcp_con->sleep_count = 0;
tcp_con->connected_time = 0;
tcp_con->status = TCP_CONN_VALID;
tcp_con->unsleep = 0;
return 0;
}
/* Send a TCP routing request.
*
* return 0 on success.
* return -1 on failure.
*/
static int send_tcp_relay_routing_request(TCP_Connections *tcp_c, int tcp_connections_number, uint8_t *public_key)
{
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
if (tcp_con->status == TCP_CONN_SLEEPING)
return -1;
if (send_routing_request(tcp_con->connection, public_key) != 1)
return -1;
return 0;
}
static int tcp_response_callback(void *object, uint8_t connection_id, const uint8_t *public_key)
{
TCP_Client_Connection *TCP_client_con = object;
TCP_Connections *tcp_c = TCP_client_con->custom_object;
unsigned int tcp_connections_number = TCP_client_con->custom_uint;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
int connections_number = find_tcp_connection_to(tcp_c, public_key);
if (connections_number == -1)
return -1;
TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
if (con_to == NULL)
return -1;
if (set_tcp_connection_status(con_to, tcp_connections_number, TCP_CONNECTIONS_STATUS_REGISTERED, connection_id) == -1)
return -1;
set_tcp_connection_number(tcp_con->connection, connection_id, connections_number);
return 0;
}
static int tcp_status_callback(void *object, uint32_t number, uint8_t connection_id, uint8_t status)
{
TCP_Client_Connection *TCP_client_con = object;
TCP_Connections *tcp_c = TCP_client_con->custom_object;
unsigned int tcp_connections_number = TCP_client_con->custom_uint;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
TCP_Connection_to *con_to = get_connection(tcp_c, number);
if (!con_to || !tcp_con)
return -1;
if (status == 1) {
if (set_tcp_connection_status(con_to, tcp_connections_number, TCP_CONNECTIONS_STATUS_REGISTERED, connection_id) == -1)
return -1;
--tcp_con->lock_count;
if (con_to->status == TCP_CONN_SLEEPING) {
--tcp_con->sleep_count;
}
} else if (status == 2) {
if (set_tcp_connection_status(con_to, tcp_connections_number, TCP_CONNECTIONS_STATUS_ONLINE, connection_id) == -1)
return -1;
++tcp_con->lock_count;
if (con_to->status == TCP_CONN_SLEEPING) {
++tcp_con->sleep_count;
}
}
return 0;
}
static int tcp_data_callback(void *object, uint32_t number, uint8_t connection_id, const uint8_t *data, uint16_t length)
{
if (length == 0)
return -1;
TCP_Client_Connection *TCP_client_con = object;
TCP_Connections *tcp_c = TCP_client_con->custom_object;
unsigned int tcp_connections_number = TCP_client_con->custom_uint;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
TCP_Connection_to *con_to = get_connection(tcp_c, number);
if (!con_to)
return -1;
if (tcp_c->tcp_data_callback)
tcp_c->tcp_data_callback(tcp_c->tcp_data_callback_object, con_to->id, data, length);
return 0;
}
static int tcp_oob_callback(void *object, const uint8_t *public_key, const uint8_t *data, uint16_t length)
{
if (length == 0)
return -1;
TCP_Client_Connection *TCP_client_con = object;
TCP_Connections *tcp_c = TCP_client_con->custom_object;
unsigned int tcp_connections_number = TCP_client_con->custom_uint;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
/* TODO: optimize */
int connections_number = find_tcp_connection_to(tcp_c, public_key);
TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
if (con_to && tcp_connection_in_conn(con_to, tcp_connections_number)) {
return tcp_data_callback(object, connections_number, 0, data, length);
} else {
if (tcp_c->tcp_oob_callback)
tcp_c->tcp_oob_callback(tcp_c->tcp_oob_callback_object, public_key, tcp_connections_number, data, length);
}
return 0;
}
static int tcp_onion_callback(void *object, const uint8_t *data, uint16_t length)
{
TCP_Connections *tcp_c = object;
if (tcp_c->tcp_onion_callback)
tcp_c->tcp_onion_callback(tcp_c->tcp_onion_callback_object, data, length);
return 0;
}
/* Set callbacks for the TCP relay connection.
*
* return 0 on success.
* return -1 on failure.
*/
static int tcp_relay_set_callbacks(TCP_Connections *tcp_c, int tcp_connections_number)
{
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
TCP_Client_Connection *con = tcp_con->connection;
con->custom_object = tcp_c;
con->custom_uint = tcp_connections_number;
onion_response_handler(con, &tcp_onion_callback, tcp_c);
routing_response_handler(con, &tcp_response_callback, con);
routing_status_handler(con, &tcp_status_callback, con);
routing_data_handler(con, &tcp_data_callback, con);
oob_data_handler(con, &tcp_oob_callback, con);
return 0;
}
static int tcp_relay_on_online(TCP_Connections *tcp_c, int tcp_connections_number)
{
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
unsigned int i, sent = 0;
for (i = 0; i < tcp_c->connections_length; ++i) {
TCP_Connection_to *con_to = get_connection(tcp_c, i);
if (con_to) {
if (tcp_connection_in_conn(con_to, tcp_connections_number)) {
if (send_tcp_relay_routing_request(tcp_c, tcp_connections_number, con_to->public_key) == 0) {
++sent;
}
}
}
}
tcp_relay_set_callbacks(tcp_c, tcp_connections_number);
tcp_con->status = TCP_CONN_CONNECTED;
/* If this connection isn't used by any connection, we don't need to wait for them to come online. */
if (sent) {
tcp_con->connected_time = unix_time();
} else {
tcp_con->connected_time = 0;
}
if (tcp_c->onion_status && tcp_c->onion_num_conns < NUM_ONION_TCP_CONNECTIONS) {
tcp_con->onion = 1;
++tcp_c->onion_num_conns;
}
return 0;
}
static int add_tcp_relay_instance(TCP_Connections *tcp_c, IP_Port ip_port, const uint8_t *relay_pk)
{
if (ip_port.ip.family == TCP_INET) {
ip_port.ip.family = AF_INET;
} else if (ip_port.ip.family == TCP_INET6) {
ip_port.ip.family = AF_INET6;
}
if (ip_port.ip.family != AF_INET && ip_port.ip.family != AF_INET6)
return -1;
int tcp_connections_number = create_tcp_connection(tcp_c);
if (tcp_connections_number == -1)
return -1;
TCP_con *tcp_con = &tcp_c->tcp_connections[tcp_connections_number];
tcp_con->connection = new_TCP_connection(ip_port, relay_pk, tcp_c->self_public_key, tcp_c->self_secret_key,
&tcp_c->proxy_info);
if (!tcp_con->connection)
return -1;
tcp_con->status = TCP_CONN_VALID;
return tcp_connections_number;
}
/* Add a TCP relay to the TCP_Connections instance.
*
* return 0 on success.
* return -1 on failure.
*/
int add_tcp_relay_global(TCP_Connections *tcp_c, IP_Port ip_port, const uint8_t *relay_pk)
{
int tcp_connections_number = find_tcp_connection_relay(tcp_c, relay_pk);
if (tcp_connections_number != -1)
return -1;
if (add_tcp_relay_instance(tcp_c, ip_port, relay_pk) == -1)
return -1;
return 0;
}
/* Add a TCP relay tied to a connection.
*
* return 0 on success.
* return -1 on failure.
*/
int add_tcp_number_relay_connection(TCP_Connections *tcp_c, int connections_number, unsigned int tcp_connections_number)
{
TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
if (!con_to)
return -1;
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
if (con_to->status != TCP_CONN_SLEEPING && tcp_con->status == TCP_CONN_SLEEPING) {
tcp_con->unsleep = 1;
}
if (add_tcp_connection_to_conn(con_to, tcp_connections_number) == -1)
return -1;
if (tcp_con->status == TCP_CONN_CONNECTED) {
if (send_tcp_relay_routing_request(tcp_c, tcp_connections_number, con_to->public_key) == 0) {
tcp_con->connected_time = unix_time();
}
}
return 0;
}
/* Add a TCP relay tied to a connection.
*
* This should be called with the same relay by two peers who want to create a TCP connection with each other.
*
* return 0 on success.
* return -1 on failure.
*/
int add_tcp_relay_connection(TCP_Connections *tcp_c, int connections_number, IP_Port ip_port, const uint8_t *relay_pk)
{
TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
if (!con_to)
return -1;
int tcp_connections_number = find_tcp_connection_relay(tcp_c, relay_pk);
if (tcp_connections_number != -1) {
return add_tcp_number_relay_connection(tcp_c, connections_number, tcp_connections_number);
} else {
if (online_tcp_connection_from_conn(con_to) >= RECOMMENDED_FRIEND_TCP_CONNECTIONS) {
return -1;
}
int tcp_connections_number = add_tcp_relay_instance(tcp_c, ip_port, relay_pk);
TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
if (!tcp_con)
return -1;
if (add_tcp_connection_to_conn(con_to, tcp_connections_number) == -1) {
return -1;
}
return 0;
}
}
/* return number of online tcp relays tied to the connection on success.
* return 0 on failure.
*/
unsigned int tcp_connection_to_online_tcp_relays(TCP_Connections *tcp_c, int connections_number)
{
TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
if (!con_to)
return 0;
return online_tcp_connection_from_conn(con_to);
}
/* Copy a maximum of max_num TCP relays we are connected to to tcp_relays.
* NOTE that the family of the copied ip ports will be set to TCP_INET or TCP_INET6.
*
* return number of relays copied to tcp_relays on success.
* return 0 on failure.
*/
unsigned int tcp_copy_connected_relays(TCP_Connections *tcp_c, Node_format *tcp_relays, uint16_t max_num)
{
unsigned int i, copied = 0, r = rand();
for (i = 0; (i < tcp_c->tcp_connections_length) && (copied < max_num); ++i) {
TCP_con *tcp_con = get_tcp_connection(tcp_c, (i + r) % tcp_c->tcp_connections_length);
if (!tcp_con) {
continue;
}
if (tcp_con->status == TCP_CONN_CONNECTED) {
memcpy(tcp_relays[copied].public_key, tcp_con->connection->public_key, crypto_box_PUBLICKEYBYTES);
tcp_relays[copied].ip_port = tcp_con->connection->ip_port;
if (tcp_relays[copied].ip_port.ip.family == AF_INET) {
tcp_relays[copied].ip_port.ip.family = TCP_INET;
} else if (tcp_relays[copied].ip_port.ip.family == AF_INET6) {
tcp_relays[copied].ip_port.ip.family = TCP_INET6;
}
++copied;
}
}
return copied;
}
/* Set if we want TCP_connection to allocate some connection for onion use.
*
* If status is 1, allocate some connections. if status is 0, don't.
*
* return 0 on success.
* return -1 on failure.
*/
int set_tcp_onion_status(TCP_Connections *tcp_c, _Bool status)
{
if (tcp_c->onion_status == status)
return -1;
if (status) {
unsigned int i;
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
TCP_con *tcp_con = get_tcp_connection(tcp_c, i);
if (tcp_con) {
if (tcp_con->status == TCP_CONN_CONNECTED && !tcp_con->onion) {
++tcp_c->onion_num_conns;
tcp_con->onion = 1;
}
}
if (tcp_c->onion_num_conns >= NUM_ONION_TCP_CONNECTIONS)
break;
}
if (tcp_c->onion_num_conns < NUM_ONION_TCP_CONNECTIONS) {
unsigned int wakeup = NUM_ONION_TCP_CONNECTIONS - tcp_c->onion_num_conns;
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
TCP_con *tcp_con = get_tcp_connection(tcp_c, i);
if (tcp_con) {
if (tcp_con->status == TCP_CONN_SLEEPING) {
tcp_con->unsleep = 1;
}
}
if (!wakeup)
break;
}
}
tcp_c->onion_status = 1;
} else {
unsigned int i;
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
TCP_con *tcp_con = get_tcp_connection(tcp_c, i);
if (tcp_con) {
if (tcp_con->onion) {
--tcp_c->onion_num_conns;
tcp_con->onion = 0;
}
}
}
tcp_c->onion_status = 0;
}
return 0;
}
/* Returns a new TCP_Connections object associated with the secret_key.
*
* In order for others to connect to this instance new_tcp_connection_to() must be called with the
* public_key associated with secret_key.
*
* Returns NULL on failure.
*/
TCP_Connections *new_tcp_connections(const uint8_t *secret_key, TCP_Proxy_Info *proxy_info)
{
if (secret_key == NULL)
return NULL;
TCP_Connections *temp = calloc(1, sizeof(TCP_Connections));
if (temp == NULL)
return NULL;
memcpy(temp->self_secret_key, secret_key, crypto_box_SECRETKEYBYTES);
crypto_scalarmult_curve25519_base(temp->self_public_key, temp->self_secret_key);
temp->proxy_info = *proxy_info;
return temp;
}
static void do_tcp_conns(TCP_Connections *tcp_c)
{
unsigned int i;
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
TCP_con *tcp_con = get_tcp_connection(tcp_c, i);
if (tcp_con) {
if (tcp_con->status != TCP_CONN_SLEEPING) {
do_TCP_connection(tcp_con->connection);
/* callbacks can change TCP connection address. */
tcp_con = get_tcp_connection(tcp_c, i);
if (tcp_con->connection->status == TCP_CLIENT_DISCONNECTED) {
if (tcp_con->status == TCP_CONN_CONNECTED) {
reconnect_tcp_relay_connection(tcp_c, i);
} else {
kill_tcp_relay_connection(tcp_c, i);
}
continue;
}
if (tcp_con->status == TCP_CONN_VALID && tcp_con->connection->status == TCP_CLIENT_CONFIRMED) {
tcp_relay_on_online(tcp_c, i);
}
if (tcp_con->status == TCP_CONN_CONNECTED && !tcp_con->onion && tcp_con->lock_count
&& tcp_con->lock_count == tcp_con->sleep_count
&& is_timeout(tcp_con->connected_time, TCP_CONNECTION_ANNOUNCE_TIMEOUT)) {
sleep_tcp_relay_connection(tcp_c, i);
}
}
if (tcp_con->status == TCP_CONN_SLEEPING && tcp_con->unsleep) {
unsleep_tcp_relay_connection(tcp_c, i);
}
}
}
}
static void kill_nonused_tcp(TCP_Connections *tcp_c)
{
if (tcp_c->tcp_connections_length == 0)
return;
unsigned int i, num_online = 0, num_kill = 0, to_kill[tcp_c->tcp_connections_length];
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
TCP_con *tcp_con = get_tcp_connection(tcp_c, i);
if (tcp_con) {
if (tcp_con->status == TCP_CONN_CONNECTED) {
if (!tcp_con->onion && !tcp_con->lock_count && is_timeout(tcp_con->connected_time, TCP_CONNECTION_ANNOUNCE_TIMEOUT)) {
to_kill[num_kill] = i;
++num_kill;
}
++num_online;
}
}
}
if (num_online <= RECOMMENDED_FRIEND_TCP_CONNECTIONS) {
return;
} else {
unsigned int n = num_online - RECOMMENDED_FRIEND_TCP_CONNECTIONS;
if (n < num_kill)
num_kill = n;
}
for (i = 0; i < num_kill; ++i) {
kill_tcp_relay_connection(tcp_c, to_kill[i]);
}
}
void do_tcp_connections(TCP_Connections *tcp_c)
{
do_tcp_conns(tcp_c);
kill_nonused_tcp(tcp_c);
}
void kill_tcp_connections(TCP_Connections *tcp_c)
{
unsigned int i;
for (i = 0; i < tcp_c->tcp_connections_length; ++i) {
kill_TCP_connection(tcp_c->tcp_connections[i].connection);
}
free(tcp_c->tcp_connections);
free(tcp_c->connections);
free(tcp_c);
}