toxcore/TCP_client.c
Rama master · réplica de lectura del repositorio original.
/* SPDX-License-Identifier: GPL-3.0-or-later
* Copyright © 2016-2026 The TokTok team.
* Copyright © 2014 Tox project.
*/
/**
* Implementation of the TCP relay client part of Tox.
*/
#include "TCP_client.h"
#include <assert.h>
#include <stdio.h>
#include <string.h>
#include "TCP_common.h"
#include "attributes.h"
#include "ccompat.h"
#include "crypto_core.h"
#include "forwarding.h"
#include "logger.h"
#include "mem.h"
#include "mono_time.h"
#include "net_profile.h"
#include "network.h"
#include "util.h"
typedef struct TCP_Client_Conn {
// TODO(iphydf): Add an enum for this.
uint8_t status; /* 0 if not used, 1 if other is offline, 2 if other is online. */
uint8_t public_key[CRYPTO_PUBLIC_KEY_SIZE];
uint32_t number;
} TCP_Client_Conn;
struct TCP_Client_Connection {
TCP_Connection con;
TCP_Client_Status status;
uint8_t self_public_key[CRYPTO_PUBLIC_KEY_SIZE]; /* our public key */
uint8_t public_key[CRYPTO_PUBLIC_KEY_SIZE]; /* public key of the server */
IP_Port ip_port; /* The ip and port of the server */
TCP_Proxy_Info proxy_info;
uint8_t recv_nonce[CRYPTO_NONCE_SIZE]; /* Nonce of received packets. */
uint16_t next_packet_length;
uint8_t temp_secret_key[CRYPTO_SECRET_KEY_SIZE];
uint64_t kill_at;
uint64_t last_pinged;
uint64_t ping_id;
uint64_t ping_response_id;
uint64_t ping_request_id;
TCP_Client_Conn connections[NUM_CLIENT_CONNECTIONS];
tcp_routing_response_cb *_Nullable response_callback;
void *_Nullable response_callback_object;
tcp_routing_status_cb *_Nullable status_callback;
void *_Nullable status_callback_object;
tcp_routing_data_cb *_Nullable data_callback;
void *_Nullable data_callback_object;
tcp_oob_data_cb *_Nullable oob_data_callback;
void *_Nullable oob_data_callback_object;
tcp_onion_response_cb *_Nullable onion_callback;
void *_Nullable onion_callback_object;
forwarded_response_cb *_Nullable forwarded_response_callback;
void *_Nullable forwarded_response_callback_object;
/* Can be used by user. */
void *_Nullable custom_object;
uint32_t custom_uint;
};
const uint8_t *tcp_con_public_key(const TCP_Client_Connection *con)
{
return con->public_key;
}
IP_Port tcp_con_ip_port(const TCP_Client_Connection *con)
{
return con->ip_port;
}
TCP_Client_Status tcp_con_status(const TCP_Client_Connection *con)
{
return con->status;
}
void *tcp_con_custom_object(const TCP_Client_Connection *con)
{
return con->custom_object;
}
uint32_t tcp_con_custom_uint(const TCP_Client_Connection *con)
{
return con->custom_uint;
}
void tcp_con_set_custom_object(TCP_Client_Connection *con, void *object)
{
con->custom_object = object;
}
void tcp_con_set_custom_uint(TCP_Client_Connection *con, uint32_t value)
{
con->custom_uint = value;
}
/**
* @retval true on success
* @retval false on failure
*/
static bool connect_sock_to(const Network *_Nonnull ns, const Logger *_Nonnull logger, const Memory *_Nonnull mem, Socket sock, const IP_Port *_Nonnull ip_port,
const TCP_Proxy_Info *_Nonnull proxy_info)
{
Net_Err_Connect err;
if (proxy_info->proxy_type != TCP_PROXY_NONE) {
net_connect(ns, mem, logger, sock, &proxy_info->ip_port, &err);
} else {
net_connect(ns, mem, logger, sock, ip_port, &err);
}
switch (err) {
case NET_ERR_CONNECT_OK:
case NET_ERR_CONNECT_FAILED: {
/* nonblocking socket, connect will never return success */
return true;
}
case NET_ERR_CONNECT_INVALID_FAMILY:
return false;
}
LOGGER_ERROR(logger, "unexpected error code %s from net_connect", net_err_connect_to_string(err));
return false;
}
/**
* @retval 1 on success.
* @retval 0 on failure.
*/
static int proxy_http_generate_connection_request(TCP_Client_Connection *_Nonnull tcp_conn)
{
const char one[] = "CONNECT ";
const char two[] = " HTTP/1.1\nHost: ";
const char three[] = "\r\n\r\n";
char ip[TOX_INET6_ADDRSTRLEN];
if (!ip_parse_addr(&tcp_conn->ip_port.ip, ip, sizeof(ip))) {
return 0;
}
const uint16_t port = net_ntohs(tcp_conn->ip_port.port);
const int written = snprintf((char *)tcp_conn->con.last_packet, MAX_PACKET_SIZE, "%s%s:%hu%s%s:%hu%s", one, ip, port,
two, ip, port, three);
if (written < 0 || MAX_PACKET_SIZE < written) {
return 0;
}
tcp_conn->con.last_packet_length = written;
tcp_conn->con.last_packet_sent = 0;
return 1;
}
/**
* @retval 1 on success.
* @retval 0 if no data received.
* @retval -1 on failure (connection refused).
*/
static int proxy_http_read_connection_response(const Logger *_Nonnull logger, const TCP_Client_Connection *_Nonnull tcp_conn)
{
const char success[] = "200";
uint8_t data[16]; // draining works the best if the length is a power of 2
const TCP_Connection *con0 = &tcp_conn->con;
const int ret = read_tcp_packet(logger, con0->mem, con0->ns, con0->sock, data, sizeof(data) - 1, &con0->ip_port);
if (ret == -1) {
return 0;
}
data[sizeof(data) - 1] = 0;
if (strstr((const char *)data, success) != nullptr) {
// drain all data
uint16_t data_left = net_socket_data_recv_buffer(tcp_conn->con.ns, tcp_conn->con.sock);
while (data_left > 0) {
uint8_t temp_data[16];
const uint16_t temp_data_size = min_u16(data_left, sizeof(temp_data));
const TCP_Connection *con = &tcp_conn->con;
if (read_tcp_packet(logger, con->mem, con->ns, con->sock, temp_data, temp_data_size,
&con->ip_port) == -1) {
LOGGER_ERROR(logger, "failed to drain TCP data (but ignoring failure)");
return 1;
}
data_left -= temp_data_size;
}
return 1;
}
return -1;
}
enum Tcp_Socks5_Proxy_Hs {
TCP_SOCKS5_PROXY_HS_VERSION_SOCKS5 = 0x05,
TCP_SOCKS5_PROXY_HS_COMM_ESTABLISH_REQUEST = 0x01,
TCP_SOCKS5_PROXY_HS_COMM_REQUEST_GRANTED = 0x00,
TCP_SOCKS5_PROXY_HS_AUTH_METHODS_SUPPORTED = 0x01,
TCP_SOCKS5_PROXY_HS_NO_AUTH = 0x00,
TCP_SOCKS5_PROXY_HS_RESERVED = 0x00,
TCP_SOCKS5_PROXY_HS_ADDR_TYPE_IPV4 = 0x01,
TCP_SOCKS5_PROXY_HS_ADDR_TYPE_IPV6 = 0x04,
};
static void proxy_socks5_generate_greetings(TCP_Client_Connection *_Nonnull tcp_conn)
{
tcp_conn->con.last_packet[0] = TCP_SOCKS5_PROXY_HS_VERSION_SOCKS5;
tcp_conn->con.last_packet[1] = TCP_SOCKS5_PROXY_HS_AUTH_METHODS_SUPPORTED;
tcp_conn->con.last_packet[2] = TCP_SOCKS5_PROXY_HS_NO_AUTH;
tcp_conn->con.last_packet_length = 3;
tcp_conn->con.last_packet_sent = 0;
}
/**
* @retval 1 on success.
* @retval 0 if no data received.
* @retval -1 on failure (connection refused).
*/
static int socks5_read_handshake_response(const Logger *_Nonnull logger, const TCP_Client_Connection *_Nonnull tcp_conn)
{
uint8_t data[2];
const TCP_Connection *con = &tcp_conn->con;
const int ret = read_tcp_packet(logger, con->mem, con->ns, con->sock, data, sizeof(data), &con->ip_port);
if (ret == -1) {
return 0;
}
if (data[0] == TCP_SOCKS5_PROXY_HS_VERSION_SOCKS5 && data[1] == TCP_SOCKS5_PROXY_HS_COMM_REQUEST_GRANTED) {
return 1;
}
return -1;
}
static void proxy_socks5_generate_connection_request(TCP_Client_Connection *_Nonnull tcp_conn)
{
tcp_conn->con.last_packet[0] = TCP_SOCKS5_PROXY_HS_VERSION_SOCKS5;
tcp_conn->con.last_packet[1] = TCP_SOCKS5_PROXY_HS_COMM_ESTABLISH_REQUEST;
tcp_conn->con.last_packet[2] = TCP_SOCKS5_PROXY_HS_RESERVED;
uint16_t length = 3;
if (net_family_is_ipv4(tcp_conn->ip_port.ip.family)) {
tcp_conn->con.last_packet[3] = TCP_SOCKS5_PROXY_HS_ADDR_TYPE_IPV4;
++length;
memcpy(tcp_conn->con.last_packet + length, tcp_conn->ip_port.ip.ip.v4.uint8, sizeof(IP4));
length += sizeof(IP4);
} else {
tcp_conn->con.last_packet[3] = TCP_SOCKS5_PROXY_HS_ADDR_TYPE_IPV6;
++length;
memcpy(tcp_conn->con.last_packet + length, tcp_conn->ip_port.ip.ip.v6.uint8, sizeof(IP6));
length += sizeof(IP6);
}
memcpy(tcp_conn->con.last_packet + length, &tcp_conn->ip_port.port, sizeof(uint16_t));
length += sizeof(uint16_t);
tcp_conn->con.last_packet_length = length;
tcp_conn->con.last_packet_sent = 0;
}
/**
* @retval 1 on success.
* @retval 0 if no data received.
* @retval -1 on failure (connection refused).
*/
static int proxy_socks5_read_connection_response(const Logger *_Nonnull logger, const TCP_Client_Connection *_Nonnull tcp_conn)
{
if (net_family_is_ipv4(tcp_conn->ip_port.ip.family)) {
uint8_t data[4 + sizeof(IP4) + sizeof(uint16_t)];
const TCP_Connection *con = &tcp_conn->con;
const int ret = read_tcp_packet(logger, con->mem, con->ns, con->sock, data, sizeof(data), &con->ip_port);
if (ret == -1) {
return 0;
}
if (data[0] == TCP_SOCKS5_PROXY_HS_VERSION_SOCKS5 && data[1] == TCP_SOCKS5_PROXY_HS_COMM_REQUEST_GRANTED) {
return 1;
}
} else {
uint8_t data[4 + sizeof(IP6) + sizeof(uint16_t)];
const TCP_Connection *con = &tcp_conn->con;
const int ret = read_tcp_packet(logger, con->mem, con->ns, con->sock, data, sizeof(data), &con->ip_port);
if (ret == -1) {
return 0;
}
if (data[0] == TCP_SOCKS5_PROXY_HS_VERSION_SOCKS5 && data[1] == TCP_SOCKS5_PROXY_HS_COMM_REQUEST_GRANTED) {
return 1;
}
}
return -1;
}
/**
* @retval 0 on success.
* @retval -1 on failure.
*/
static int generate_handshake(TCP_Client_Connection *_Nonnull tcp_conn)
{
uint8_t plain[CRYPTO_PUBLIC_KEY_SIZE + CRYPTO_NONCE_SIZE];
crypto_new_keypair(tcp_conn->con.rng, plain, tcp_conn->temp_secret_key);
random_nonce(tcp_conn->con.rng, tcp_conn->con.sent_nonce);
memcpy(plain + CRYPTO_PUBLIC_KEY_SIZE, tcp_conn->con.sent_nonce, CRYPTO_NONCE_SIZE);
memcpy(tcp_conn->con.last_packet, tcp_conn->self_public_key, CRYPTO_PUBLIC_KEY_SIZE);
random_nonce(tcp_conn->con.rng, tcp_conn->con.last_packet + CRYPTO_PUBLIC_KEY_SIZE);
const int len = encrypt_data_symmetric(tcp_conn->con.mem, tcp_conn->con.shared_key, tcp_conn->con.last_packet + CRYPTO_PUBLIC_KEY_SIZE, plain,
sizeof(plain), tcp_conn->con.last_packet + CRYPTO_PUBLIC_KEY_SIZE + CRYPTO_NONCE_SIZE);
if (len != sizeof(plain) + CRYPTO_MAC_SIZE) {
return -1;
}
tcp_conn->con.last_packet_length = CRYPTO_PUBLIC_KEY_SIZE + CRYPTO_NONCE_SIZE + sizeof(plain) + CRYPTO_MAC_SIZE;
tcp_conn->con.last_packet_sent = 0;
return 0;
}
/**
* @param data must be of length TCP_SERVER_HANDSHAKE_SIZE
*
* @retval 0 on success.
* @retval -1 on failure.
*/
static int handle_handshake(TCP_Client_Connection *_Nonnull tcp_conn, const uint8_t *_Nonnull data)
{
uint8_t plain[CRYPTO_PUBLIC_KEY_SIZE + CRYPTO_NONCE_SIZE];
const int len = decrypt_data_symmetric(tcp_conn->con.mem, tcp_conn->con.shared_key, data, data + CRYPTO_NONCE_SIZE,
TCP_SERVER_HANDSHAKE_SIZE - CRYPTO_NONCE_SIZE, plain);
if (len != sizeof(plain)) {
return -1;
}
memcpy(tcp_conn->recv_nonce, plain + CRYPTO_PUBLIC_KEY_SIZE, CRYPTO_NONCE_SIZE);
encrypt_precompute(plain, tcp_conn->temp_secret_key, tcp_conn->con.shared_key);
crypto_memzero(tcp_conn->temp_secret_key, CRYPTO_SECRET_KEY_SIZE);
return 0;
}
/**
* @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure (connection must be killed).
*/
int send_routing_request(const Logger *logger, TCP_Client_Connection *con, const uint8_t *public_key)
{
uint8_t packet[1 + CRYPTO_PUBLIC_KEY_SIZE];
packet[0] = TCP_PACKET_ROUTING_REQUEST;
memcpy(packet + 1, public_key, CRYPTO_PUBLIC_KEY_SIZE);
return write_packet_tcp_secure_connection(logger, &con->con, packet, sizeof(packet), true);
}
void routing_response_handler(TCP_Client_Connection *con, tcp_routing_response_cb *response_callback, void *object)
{
con->response_callback = response_callback;
con->response_callback_object = object;
}
void routing_status_handler(TCP_Client_Connection *con, tcp_routing_status_cb *status_callback, void *object)
{
con->status_callback = status_callback;
con->status_callback_object = object;
}
static int tcp_send_ping_response(const Logger *_Nonnull logger, TCP_Client_Connection *_Nonnull con);
static int tcp_send_ping_request(const Logger *_Nonnull logger, TCP_Client_Connection *_Nonnull con);
/**
* @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure.
*/
int send_data(const Logger *logger, TCP_Client_Connection *con, uint8_t con_id, const uint8_t *data, uint16_t length)
{
if (con_id >= NUM_CLIENT_CONNECTIONS) {
return -1;
}
if (con->connections[con_id].status != 2) {
return -1;
}
if (tcp_send_ping_response(logger, con) == 0 || tcp_send_ping_request(logger, con) == 0) {
return 0;
}
if (1 + length > MAX_PACKET_SIZE) {
LOGGER_ERROR(logger, "Packet length too long: %u", length);
return -1;
}
const uint16_t packet_size = 1 + length;
VLA(uint8_t, packet, packet_size);
packet[0] = con_id + NUM_RESERVED_PORTS;
memcpy(packet + 1, data, length);
return write_packet_tcp_secure_connection(logger, &con->con, packet, packet_size, false);
}
/**
* @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure.
*/
int send_oob_packet(const Logger *logger, TCP_Client_Connection *con, const uint8_t *public_key, const uint8_t *data,
uint16_t length)
{
if (length == 0 || length > TCP_MAX_OOB_DATA_LENGTH) {
return -1;
}
const uint16_t packet_size = 1 + CRYPTO_PUBLIC_KEY_SIZE + length;
VLA(uint8_t, packet, packet_size);
packet[0] = TCP_PACKET_OOB_SEND;
memcpy(packet + 1, public_key, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(packet + 1 + CRYPTO_PUBLIC_KEY_SIZE, data, length);
return write_packet_tcp_secure_connection(logger, &con->con, packet, packet_size, false);
}
/** @brief Set the number that will be used as an argument in the callbacks related to con_id.
*
* When not set by this function, the number is -1.
*
* return 0 on success.
* return -1 on failure.
*/
int set_tcp_connection_number(TCP_Client_Connection *con, uint8_t con_id, uint32_t number)
{
if (con_id >= NUM_CLIENT_CONNECTIONS) {
return -1;
}
if (con->connections[con_id].status == 0) {
return -1;
}
con->connections[con_id].number = number;
return 0;
}
void routing_data_handler(TCP_Client_Connection *con, tcp_routing_data_cb *data_callback, void *object)
{
con->data_callback = data_callback;
con->data_callback_object = object;
}
void oob_data_handler(TCP_Client_Connection *con, tcp_oob_data_cb *oob_data_callback, void *object)
{
con->oob_data_callback = oob_data_callback;
con->oob_data_callback_object = object;
}
/**
* @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure (connection must be killed).
*/
static int client_send_disconnect_notification(const Logger *_Nonnull logger, TCP_Client_Connection *_Nonnull con, uint8_t id)
{
uint8_t packet[1 + 1];
packet[0] = TCP_PACKET_DISCONNECT_NOTIFICATION;
packet[1] = id;
return write_packet_tcp_secure_connection(logger, &con->con, packet, sizeof(packet), true);
}
/**
* @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure (connection must be killed).
*/
static int tcp_send_ping_request(const Logger *logger, TCP_Client_Connection *con)
{
if (con->ping_request_id == 0) {
return 1;
}
uint8_t packet[1 + sizeof(uint64_t)];
packet[0] = TCP_PACKET_PING;
memcpy(packet + 1, &con->ping_request_id, sizeof(uint64_t));
const int ret = write_packet_tcp_secure_connection(logger, &con->con, packet, sizeof(packet), true);
if (ret == 1) {
con->ping_request_id = 0;
}
return ret;
}
/**
* @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure (connection must be killed).
*/
static int tcp_send_ping_response(const Logger *logger, TCP_Client_Connection *con)
{
if (con->ping_response_id == 0) {
return 1;
}
uint8_t packet[1 + sizeof(uint64_t)];
packet[0] = TCP_PACKET_PONG;
memcpy(packet + 1, &con->ping_response_id, sizeof(uint64_t));
const int ret = write_packet_tcp_secure_connection(logger, &con->con, packet, sizeof(packet), true);
if (ret == 1) {
con->ping_response_id = 0;
}
return ret;
}
/**
* @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure (connection must be killed).
*/
int send_disconnect_request(const Logger *logger, TCP_Client_Connection *con, uint8_t con_id)
{
if (con_id >= NUM_CLIENT_CONNECTIONS) {
return -1;
}
con->connections[con_id].status = 0;
con->connections[con_id].number = 0;
return client_send_disconnect_notification(logger, con, con_id + NUM_RESERVED_PORTS);
}
/**
* @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure (connection must be killed).
*/
int send_onion_request(const Logger *logger, TCP_Client_Connection *con, const uint8_t *data, uint16_t length)
{
if (1 + length > MAX_PACKET_SIZE) {
LOGGER_ERROR(logger, "Packet length too long: %u", length);
return -1;
}
const uint16_t packet_size = 1 + length;
VLA(uint8_t, packet, packet_size);
packet[0] = TCP_PACKET_ONION_REQUEST;
memcpy(packet + 1, data, length);
return write_packet_tcp_secure_connection(logger, &con->con, packet, packet_size, false);
}
void onion_response_handler(TCP_Client_Connection *con, tcp_onion_response_cb *onion_callback, void *object)
{
con->onion_callback = onion_callback;
con->onion_callback_object = object;
}
/** @retval 1 on success.
* @retval 0 if could not send packet.
* @retval -1 on failure (connection must be killed).
*/
int send_forward_request_tcp(const Logger *logger, TCP_Client_Connection *con, const IP_Port *dest, const uint8_t *data, uint16_t length)
{
if (length > MAX_FORWARD_DATA_SIZE) {
return -1;
}
VLA(uint8_t, packet, 1 + MAX_PACKED_IPPORT_SIZE + length);
packet[0] = TCP_PACKET_FORWARD_REQUEST;
const int ipport_length = pack_ip_port(logger, packet + 1, MAX_PACKED_IPPORT_SIZE, dest);
if (ipport_length == -1) {
return 0;
}
memcpy(packet + 1 + ipport_length, data, length);
return write_packet_tcp_secure_connection(logger, &con->con, packet, 1 + ipport_length + length, false);
}
void forwarding_handler(TCP_Client_Connection *con, forwarded_response_cb *forwarded_response_callback, void *object)
{
con->forwarded_response_callback = forwarded_response_callback;
con->forwarded_response_callback_object = object;
}
/** Create new TCP connection to ip_port/public_key */
TCP_Client_Connection *new_tcp_connection(
const Logger *logger, const Memory *mem, const Mono_Time *mono_time, const Random *rng, const Network *ns,
const IP_Port *ip_port, const uint8_t *public_key, const uint8_t *self_public_key, const uint8_t *self_secret_key,
const TCP_Proxy_Info *proxy_info, Net_Profile *net_profile)
{
assert(logger != nullptr);
assert(mem != nullptr);
assert(mono_time != nullptr);
assert(rng != nullptr);
assert(ns != nullptr);
if (!net_family_is_ipv4(ip_port->ip.family) && !net_family_is_ipv6(ip_port->ip.family)) {
LOGGER_ERROR(logger, "Invalid IP family: %d", ip_port->ip.family.value);
return nullptr;
}
const TCP_Proxy_Info default_proxyinfo = {{{{0}}}};
if (proxy_info == nullptr) {
proxy_info = &default_proxyinfo;
}
Family family = ip_port->ip.family;
if (proxy_info->proxy_type != TCP_PROXY_NONE) {
family = proxy_info->ip_port.ip.family;
}
const Socket sock = net_socket(ns, family, TOX_SOCK_STREAM, TOX_PROTO_TCP);
if (!sock_valid(sock)) {
LOGGER_ERROR(logger, "Failed to create TCP socket with family %d", family.value);
return nullptr;
}
if (!set_socket_nosigpipe(ns, sock)) {
LOGGER_ERROR(logger, "Failed to set TCP socket to ignore SIGPIPE");
kill_sock(ns, sock);
return nullptr;
}
if (!set_socket_nonblock(ns, sock)) {
LOGGER_ERROR(logger, "Failed to set TCP socket to non-blocking");
kill_sock(ns, sock);
return nullptr;
}
if (!connect_sock_to(ns, logger, mem, sock, ip_port, proxy_info)) {
Ip_Ntoa ip_ntoa;
LOGGER_WARNING(logger, "Failed to connect TCP socket to %s:%u",
net_ip_ntoa(&ip_port->ip, &ip_ntoa), net_ntohs(ip_port->port));
kill_sock(ns, sock);
return nullptr;
}
TCP_Client_Connection *temp = (TCP_Client_Connection *)mem_alloc(mem, sizeof(TCP_Client_Connection));
if (temp == nullptr) {
LOGGER_ERROR(logger, "Failed to allocate memory for TCP_Client_Connection");
kill_sock(ns, sock);
return nullptr;
}
temp->con.ns = ns;
temp->con.mem = mem;
temp->con.rng = rng;
temp->con.sock = sock;
temp->con.ip_port = *ip_port;
temp->con.net_profile = net_profile;
memcpy(temp->public_key, public_key, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(temp->self_public_key, self_public_key, CRYPTO_PUBLIC_KEY_SIZE);
encrypt_precompute(temp->public_key, self_secret_key, temp->con.shared_key);
temp->ip_port = *ip_port;
temp->proxy_info = *proxy_info;
switch (proxy_info->proxy_type) {
case TCP_PROXY_HTTP: {
temp->status = TCP_CLIENT_PROXY_HTTP_CONNECTING;
proxy_http_generate_connection_request(temp);
break;
}
case TCP_PROXY_SOCKS5: {
temp->status = TCP_CLIENT_PROXY_SOCKS5_CONNECTING;
proxy_socks5_generate_greetings(temp);
break;
}
case TCP_PROXY_NONE: {
temp->status = TCP_CLIENT_CONNECTING;
if (generate_handshake(temp) == -1) {
LOGGER_ERROR(logger, "Failed to generate handshake");
kill_sock(ns, sock);
mem_delete(mem, temp);
return nullptr;
}
break;
}
}
temp->kill_at = mono_time_get(mono_time) + TCP_CONNECTION_TIMEOUT;
return temp;
}
static int handle_tcp_client_routing_response(TCP_Client_Connection *_Nonnull conn, const uint8_t *_Nonnull data, uint16_t length)
{
if (length != 1 + 1 + CRYPTO_PUBLIC_KEY_SIZE) {
return -1;
}
if (data[1] < NUM_RESERVED_PORTS) {
return 0;
}
const uint8_t con_id = data[1] - NUM_RESERVED_PORTS;
if (conn->connections[con_id].status != 0) {
return 0;
}
conn->connections[con_id].status = 1;
conn->connections[con_id].number = -1;
memcpy(conn->connections[con_id].public_key, data + 2, CRYPTO_PUBLIC_KEY_SIZE);
if (conn->response_callback != nullptr) {
conn->response_callback(conn->response_callback_object, con_id, conn->connections[con_id].public_key);
}
return 0;
}
static int handle_tcp_client_connection_notification(TCP_Client_Connection *_Nonnull conn, const uint8_t *_Nonnull data, uint16_t length)
{
if (length != 1 + 1) {
return -1;
}
if (data[1] < NUM_RESERVED_PORTS) {
return -1;
}
const uint8_t con_id = data[1] - NUM_RESERVED_PORTS;
if (conn->connections[con_id].status != 1) {
return 0;
}
conn->connections[con_id].status = 2;
if (conn->status_callback != nullptr) {
conn->status_callback(conn->status_callback_object, conn->connections[con_id].number, con_id,
conn->connections[con_id].status);
}
return 0;
}
static int handle_tcp_client_disconnect_notification(TCP_Client_Connection *_Nonnull conn, const uint8_t *_Nonnull data, uint16_t length)
{
if (length != 1 + 1) {
return -1;
}
if (data[1] < NUM_RESERVED_PORTS) {
return -1;
}
const uint8_t con_id = data[1] - NUM_RESERVED_PORTS;
if (conn->connections[con_id].status == 0) {
return 0;
}
if (conn->connections[con_id].status != 2) {
return 0;
}
conn->connections[con_id].status = 1;
if (conn->status_callback != nullptr) {
conn->status_callback(conn->status_callback_object, conn->connections[con_id].number, con_id,
conn->connections[con_id].status);
}
return 0;
}
static int handle_tcp_client_ping(const Logger *_Nonnull logger, TCP_Client_Connection *_Nonnull conn, const uint8_t *_Nonnull data, uint16_t length)
{
if (length != 1 + sizeof(uint64_t)) {
return -1;
}
uint64_t ping_id;
memcpy(&ping_id, data + 1, sizeof(uint64_t));
conn->ping_response_id = ping_id;
tcp_send_ping_response(logger, conn);
return 0;
}
static int handle_tcp_client_pong(TCP_Client_Connection *_Nonnull conn, const uint8_t *_Nonnull data, uint16_t length)
{
if (length != 1 + sizeof(uint64_t)) {
return -1;
}
uint64_t ping_id;
memcpy(&ping_id, data + 1, sizeof(uint64_t));
if (ping_id != 0) {
if (ping_id == conn->ping_id) {
conn->ping_id = 0;
}
return 0;
}
return -1;
}
static int handle_tcp_client_oob_recv(TCP_Client_Connection *_Nonnull conn, const uint8_t *_Nonnull data, uint16_t length, void *_Nullable userdata)
{
if (length <= 1 + CRYPTO_PUBLIC_KEY_SIZE) {
return -1;
}
if (conn->oob_data_callback != nullptr) {
conn->oob_data_callback(conn->oob_data_callback_object, data + 1, data + 1 + CRYPTO_PUBLIC_KEY_SIZE,
length - (1 + CRYPTO_PUBLIC_KEY_SIZE), userdata);
}
return 0;
}
/**
* @retval 0 on success
* @retval -1 on failure
*/
static int handle_tcp_client_packet(const Logger *_Nonnull logger, TCP_Client_Connection *_Nonnull conn, const uint8_t *_Nonnull data,
uint16_t length, void *_Nullable userdata)
{
if (length <= 1) {
return -1;
}
netprof_record_packet(conn->con.net_profile, data[0], length, PACKET_DIRECTION_RECV);
switch (data[0]) {
case TCP_PACKET_ROUTING_RESPONSE:
return handle_tcp_client_routing_response(conn, data, length);
case TCP_PACKET_CONNECTION_NOTIFICATION:
return handle_tcp_client_connection_notification(conn, data, length);
case TCP_PACKET_DISCONNECT_NOTIFICATION:
return handle_tcp_client_disconnect_notification(conn, data, length);
case TCP_PACKET_PING:
return handle_tcp_client_ping(logger, conn, data, length);
case TCP_PACKET_PONG:
return handle_tcp_client_pong(conn, data, length);
case TCP_PACKET_OOB_RECV:
return handle_tcp_client_oob_recv(conn, data, length, userdata);
case TCP_PACKET_ONION_RESPONSE: {
if (conn->onion_callback != nullptr) {
conn->onion_callback(conn->onion_callback_object, data + 1, length - 1, userdata);
}
return 0;
}
case TCP_PACKET_FORWARDING: {
if (conn->forwarded_response_callback != nullptr) {
conn->forwarded_response_callback(conn->forwarded_response_callback_object, data + 1, length - 1, userdata);
}
return 0;
}
default: {
if (data[0] < NUM_RESERVED_PORTS) {
return -1;
}
const uint8_t con_id = data[0] - NUM_RESERVED_PORTS;
if (conn->data_callback != nullptr) {
conn->data_callback(conn->data_callback_object, conn->connections[con_id].number, con_id, data + 1, length - 1,
userdata);
}
}
}
return 0;
}
static bool tcp_process_packet(const Logger *_Nonnull logger, TCP_Client_Connection *_Nonnull conn, void *_Nullable userdata)
{
uint8_t packet[MAX_PACKET_SIZE];
const int len = read_packet_tcp_secure_connection(logger, conn->con.mem, conn->con.ns, conn->con.sock, &conn->next_packet_length, conn->con.shared_key, conn->recv_nonce, packet, sizeof(packet),
&conn->ip_port);
if (len == 0) {
return false;
}
if (len == -1) {
conn->status = TCP_CLIENT_DISCONNECTED;
return false;
}
if (handle_tcp_client_packet(logger, conn, packet, len, userdata) == -1) {
conn->status = TCP_CLIENT_DISCONNECTED;
return false;
}
return true;
}
static int do_confirmed_tcp(const Logger *_Nonnull logger, TCP_Client_Connection *_Nonnull conn, const Mono_Time *_Nonnull mono_time,
void *_Nullable userdata)
{
send_pending_data(logger, &conn->con);
tcp_send_ping_response(logger, conn);
tcp_send_ping_request(logger, conn);
if (mono_time_is_timeout(mono_time, conn->last_pinged, TCP_PING_FREQUENCY)) {
uint64_t ping_id = random_u64(conn->con.rng);
if (ping_id == 0) {
++ping_id;
}
conn->ping_request_id = ping_id;
conn->ping_id = ping_id;
tcp_send_ping_request(logger, conn);
conn->last_pinged = mono_time_get(mono_time);
}
if (conn->ping_id != 0 && mono_time_is_timeout(mono_time, conn->last_pinged, TCP_PING_TIMEOUT)) {
conn->status = TCP_CLIENT_DISCONNECTED;
return 0;
}
while (tcp_process_packet(logger, conn, userdata)) {
/* Keep reading until error or out of data. */
}
return 0;
}
/** Run the TCP connection */
void do_tcp_connection(const Logger *logger, const Mono_Time *mono_time,
TCP_Client_Connection *tcp_connection, void *userdata)
{
if (tcp_connection->status == TCP_CLIENT_DISCONNECTED) {
return;
}
if (tcp_connection->status == TCP_CLIENT_PROXY_HTTP_CONNECTING) {
if (send_pending_data(logger, &tcp_connection->con) == 0) {
const int ret = proxy_http_read_connection_response(logger, tcp_connection);
if (ret == -1) {
tcp_connection->kill_at = 0;
tcp_connection->status = TCP_CLIENT_DISCONNECTED;
}
if (ret == 1) {
generate_handshake(tcp_connection);
tcp_connection->status = TCP_CLIENT_CONNECTING;
}
}
}
if (tcp_connection->status == TCP_CLIENT_PROXY_SOCKS5_CONNECTING) {
if (send_pending_data(logger, &tcp_connection->con) == 0) {
const int ret = socks5_read_handshake_response(logger, tcp_connection);
if (ret == -1) {
tcp_connection->kill_at = 0;
tcp_connection->status = TCP_CLIENT_DISCONNECTED;
}
if (ret == 1) {
proxy_socks5_generate_connection_request(tcp_connection);
tcp_connection->status = TCP_CLIENT_PROXY_SOCKS5_UNCONFIRMED;
}
}
}
if (tcp_connection->status == TCP_CLIENT_PROXY_SOCKS5_UNCONFIRMED) {
if (send_pending_data(logger, &tcp_connection->con) == 0) {
const int ret = proxy_socks5_read_connection_response(logger, tcp_connection);
if (ret == -1) {
tcp_connection->kill_at = 0;
tcp_connection->status = TCP_CLIENT_DISCONNECTED;
}
if (ret == 1) {
generate_handshake(tcp_connection);
tcp_connection->status = TCP_CLIENT_CONNECTING;
}
}
}
if (tcp_connection->status == TCP_CLIENT_CONNECTING) {
if (send_pending_data(logger, &tcp_connection->con) == 0) {
tcp_connection->status = TCP_CLIENT_UNCONFIRMED;
}
}
if (tcp_connection->status == TCP_CLIENT_UNCONFIRMED) {
uint8_t data[TCP_SERVER_HANDSHAKE_SIZE];
const TCP_Connection *con = &tcp_connection->con;
const int len = read_tcp_packet(logger, con->mem, con->ns, con->sock, data, sizeof(data), &con->ip_port);
if (sizeof(data) == len) {
if (handle_handshake(tcp_connection, data) == 0) {
tcp_connection->kill_at = UINT64_MAX;
tcp_connection->status = TCP_CLIENT_CONFIRMED;
} else {
tcp_connection->kill_at = 0;
tcp_connection->status = TCP_CLIENT_DISCONNECTED;
}
}
}
if (tcp_connection->status == TCP_CLIENT_CONFIRMED) {
do_confirmed_tcp(logger, tcp_connection, mono_time, userdata);
}
if (tcp_connection->kill_at <= mono_time_get(mono_time)) {
tcp_connection->status = TCP_CLIENT_DISCONNECTED;
}
}
/** Kill the TCP connection */
void kill_tcp_connection(TCP_Client_Connection *tcp_connection)
{
if (tcp_connection == nullptr) {
return;
}
const Memory *mem = tcp_connection->con.mem;
wipe_priority_list(tcp_connection->con.mem, tcp_connection->con.priority_queue_start);
kill_sock(tcp_connection->con.ns, tcp_connection->con.sock);
crypto_memzero(tcp_connection, sizeof(TCP_Client_Connection));
mem_delete(mem, tcp_connection);
}