/*
* TCP_server.c -- Implementation of the TCP relay server part of Tox.
*
* Copyright (C) 2014 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 .
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "TCP_server.h"
#if !defined(_WIN32) && !defined(__WIN32__) && !defined (WIN32)
#include
#endif
#include "util.h"
/* return 1 on success
* return 0 on failure
*/
static int bind_to_port(sock_t sock, int family, uint16_t port)
{
struct sockaddr_storage addr = {0};
size_t addrsize;
if (family == AF_INET) {
struct sockaddr_in *addr4 = (struct sockaddr_in *)&addr;
addrsize = sizeof(struct sockaddr_in);
addr4->sin_family = AF_INET;
addr4->sin_port = htons(port);
} else if (family == AF_INET6) {
struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&addr;
addrsize = sizeof(struct sockaddr_in6);
addr6->sin6_family = AF_INET6;
addr6->sin6_port = htons(port);
} else {
return 0;
}
return (bind(sock, (struct sockaddr *)&addr, addrsize) == 0);
}
/* Set the size of the connection list to numfriends.
*
* return -1 if realloc fails.
* return 0 if it succeeds.
*/
static int realloc_connection(TCP_Server *TCP_server, uint32_t num)
{
if (num == 0) {
free(TCP_server->accepted_connection_array);
TCP_server->accepted_connection_array = NULL;
TCP_server->size_accepted_connections = 0;
return 0;
}
if (num == TCP_server->size_accepted_connections) {
return 0;
}
TCP_Secure_Connection *new_connections = realloc(TCP_server->accepted_connection_array,
num * sizeof(TCP_Secure_Connection));
if (new_connections == NULL)
return -1;
if (num > TCP_server->size_accepted_connections) {
uint32_t old_size = TCP_server->size_accepted_connections;
uint32_t size_new_entries = (num - old_size) * sizeof(TCP_Secure_Connection);
memset(new_connections + old_size, 0, size_new_entries);
}
TCP_server->accepted_connection_array = new_connections;
TCP_server->size_accepted_connections = num;
return 0;
}
/* return index corresponding to connection with peer on success
* return -1 on failure.
*/
static int get_TCP_connection_index(const TCP_Server *TCP_server, const uint8_t *public_key)
{
return bs_list_find(&TCP_server->accepted_key_list, public_key);
}
static int kill_accepted(TCP_Server *TCP_server, int index);
/* Add accepted TCP connection to the list.
*
* return index on success
* return -1 on failure
*/
static int add_accepted(TCP_Server *TCP_server, const TCP_Secure_Connection *con)
{
int index = get_TCP_connection_index(TCP_server, con->public_key);
if (index != -1) { /* If an old connection to the same public key exists, kill it. */
kill_accepted(TCP_server, index);
index = -1;
}
if (TCP_server->size_accepted_connections == TCP_server->num_accepted_connections) {
if (realloc_connection(TCP_server, TCP_server->size_accepted_connections + 4) == -1)
return -1;
index = TCP_server->num_accepted_connections;
} else {
uint32_t i;
for (i = TCP_server->size_accepted_connections; i != 0; --i) {
if (TCP_server->accepted_connection_array[i - 1].status == TCP_STATUS_NO_STATUS) {
index = i - 1;
break;
}
}
}
if (index == -1) {
fprintf(stderr, "FAIL index is -1\n");
return -1;
}
if (!bs_list_add(&TCP_server->accepted_key_list, con->public_key, index))
return -1;
memcpy(&TCP_server->accepted_connection_array[index], con, sizeof(TCP_Secure_Connection));
TCP_server->accepted_connection_array[index].status = TCP_STATUS_CONFIRMED;
++TCP_server->num_accepted_connections;
TCP_server->accepted_connection_array[index].identifier = ++TCP_server->counter;
TCP_server->accepted_connection_array[index].last_pinged = unix_time();
TCP_server->accepted_connection_array[index].ping_id = 0;
return index;
}
/* Delete accepted connection from list.
*
* return 0 on success
* return -1 on failure
*/
static int del_accepted(TCP_Server *TCP_server, int index)
{
if ((uint32_t)index >= TCP_server->size_accepted_connections)
return -1;
if (TCP_server->accepted_connection_array[index].status == TCP_STATUS_NO_STATUS)
return -1;
if (!bs_list_remove(&TCP_server->accepted_key_list, TCP_server->accepted_connection_array[index].public_key, index))
return -1;
memset(&TCP_server->accepted_connection_array[index], 0, sizeof(TCP_Secure_Connection));
--TCP_server->num_accepted_connections;
if (TCP_server->num_accepted_connections == 0)
realloc_connection(TCP_server, 0);
return 0;
}
/* Read the next two bytes in TCP stream then convert them to
* length (host byte order).
*
* return length on success
* return 0 if nothing has been read from socket.
* return ~0 on failure.
*/
uint16_t read_TCP_length(sock_t sock)
{
#if defined(_WIN32) || defined(__WIN32__) || defined (WIN32)
unsigned long count = 0;
ioctlsocket(sock, FIONREAD, &count);
#else
int count = 0;
ioctl(sock, FIONREAD, &count);
#endif
if ((unsigned int)count >= sizeof(uint16_t)) {
uint16_t length;
int len = recv(sock, (uint8_t *)&length, sizeof(uint16_t), MSG_NOSIGNAL);
if (len != sizeof(uint16_t)) {
fprintf(stderr, "FAIL recv packet\n");
return 0;
}
length = ntohs(length);
if (length > MAX_PACKET_SIZE) {
return ~0;
}
return length;
}
return 0;
}
/* Read length bytes from socket.
*
* return length on success
* return -1 on failure/no data in buffer.
*/
int read_TCP_packet(sock_t sock, uint8_t *data, uint16_t length)
{
#if defined(_WIN32) || defined(__WIN32__) || defined (WIN32)
unsigned long count = 0;
ioctlsocket(sock, FIONREAD, &count);
#else
int count = 0;
ioctl(sock, FIONREAD, &count);
#endif
if (count >= length) {
int len = recv(sock, data, length, MSG_NOSIGNAL);
if (len != length) {
fprintf(stderr, "FAIL recv packet\n");
return -1;
}
return len;
}
return -1;
}
/* return length of received packet on success.
* return 0 if could not read any packet.
* return -1 on failure (connection must be killed).
*/
int read_packet_TCP_secure_connection(sock_t sock, uint16_t *next_packet_length, const uint8_t *shared_key,
uint8_t *recv_nonce, uint8_t *data, uint16_t max_len)
{
if (*next_packet_length == 0) {
uint16_t len = read_TCP_length(sock);
if (len == (uint16_t)~0)
return -1;
if (len == 0)
return 0;
*next_packet_length = len;
}
if (max_len + crypto_box_MACBYTES < *next_packet_length)
return -1;
uint8_t data_encrypted[*next_packet_length];
int len_packet = read_TCP_packet(sock, data_encrypted, *next_packet_length);
if (len_packet != *next_packet_length)
return 0;
*next_packet_length = 0;
int len = decrypt_data_symmetric(shared_key, recv_nonce, data_encrypted, len_packet, data);
if (len + crypto_box_MACBYTES != len_packet)
return -1;
increment_nonce(recv_nonce);
return len;
}
/* return 0 if pending data was sent completely
* return -1 if it wasn't
*/
static int send_pending_data(TCP_Secure_Connection *con)
{
if (con->last_packet_length == 0) {
return 0;
}
uint16_t left = con->last_packet_length - con->last_packet_sent;
int len = send(con->sock, con->last_packet + con->last_packet_sent, left, MSG_NOSIGNAL);
if (len <= 0)
return -1;
if (len == left) {
con->last_packet_length = 0;
con->last_packet_sent = 0;
return 0;
}
if (len > left)
return -1;
con->last_packet_sent += len;
return -1;
}
/* return 1 on success.
* return 0 if could not send packet.
* return -1 on failure (connection must be killed).
*/
static int write_packet_TCP_secure_connection(TCP_Secure_Connection *con, const uint8_t *data, uint16_t length)
{
if (length + crypto_box_MACBYTES > MAX_PACKET_SIZE)
return -1;
if (send_pending_data(con) == -1)
return 0;
uint8_t packet[sizeof(uint16_t) + length + crypto_box_MACBYTES];
uint16_t c_length = htons(length + crypto_box_MACBYTES);
memcpy(packet, &c_length, sizeof(uint16_t));
int len = encrypt_data_symmetric(con->shared_key, con->sent_nonce, data, length, packet + sizeof(uint16_t));
if ((unsigned int)len != (sizeof(packet) - sizeof(uint16_t)))
return -1;
increment_nonce(con->sent_nonce);
len = send(con->sock, packet, sizeof(packet), MSG_NOSIGNAL);
if ((unsigned int)len == sizeof(packet))
return 1;
if (len <= 0)
return 0;
memcpy(con->last_packet, packet, length);
con->last_packet_length = sizeof(packet);
con->last_packet_sent = len;
return 1;
}
/* Kill a TCP_Secure_Connection
*/
static void kill_TCP_connection(TCP_Secure_Connection *con)
{
kill_sock(con->sock);
memset(con, 0, sizeof(TCP_Secure_Connection));
}
static int rm_connection_index(TCP_Server *TCP_server, TCP_Secure_Connection *con, uint8_t con_number);
/* Kill an accepted TCP_Secure_Connection
*
* return -1 on failure.
* return 0 on success.
*/
static int kill_accepted(TCP_Server *TCP_server, int index)
{
if ((uint32_t)index >= TCP_server->size_accepted_connections)
return -1;
uint32_t i;
for (i = 0; i < NUM_CLIENT_CONNECTIONS; ++i) {
rm_connection_index(TCP_server, &TCP_server->accepted_connection_array[index], i);
}
sock_t sock = TCP_server->accepted_connection_array[index].sock;
if (del_accepted(TCP_server, index) != 0)
return -1;
kill_sock(sock);
return 0;
}
/* return 1 if everything went well.
* return -1 if the connection must be killed.
*/
static int handle_TCP_handshake(TCP_Secure_Connection *con, const uint8_t *data, uint16_t length,
const uint8_t *self_secret_key)
{
if (length != TCP_CLIENT_HANDSHAKE_SIZE)
return -1;
if (con->status != TCP_STATUS_CONNECTED)
return -1;
uint8_t shared_key[crypto_box_BEFORENMBYTES];
encrypt_precompute(data, self_secret_key, shared_key);
uint8_t plain[TCP_HANDSHAKE_PLAIN_SIZE];
int len = decrypt_data_symmetric(shared_key, data + crypto_box_PUBLICKEYBYTES,
data + crypto_box_PUBLICKEYBYTES + crypto_box_NONCEBYTES, TCP_HANDSHAKE_PLAIN_SIZE + crypto_box_MACBYTES, plain);
if (len != TCP_HANDSHAKE_PLAIN_SIZE)
return -1;
memcpy(con->public_key, data, crypto_box_PUBLICKEYBYTES);
uint8_t temp_secret_key[crypto_box_SECRETKEYBYTES];
uint8_t resp_plain[TCP_HANDSHAKE_PLAIN_SIZE];
crypto_box_keypair(resp_plain, temp_secret_key);
random_nonce(con->sent_nonce);
memcpy(resp_plain + crypto_box_PUBLICKEYBYTES, con->sent_nonce, crypto_box_NONCEBYTES);
memcpy(con->recv_nonce, plain + crypto_box_PUBLICKEYBYTES, crypto_box_NONCEBYTES);
uint8_t response[TCP_SERVER_HANDSHAKE_SIZE];
new_nonce(response);
len = encrypt_data_symmetric(shared_key, response, resp_plain, TCP_HANDSHAKE_PLAIN_SIZE,
response + crypto_box_NONCEBYTES);
if (len != TCP_HANDSHAKE_PLAIN_SIZE + crypto_box_MACBYTES)
return -1;
if (TCP_SERVER_HANDSHAKE_SIZE != send(con->sock, response, TCP_SERVER_HANDSHAKE_SIZE, MSG_NOSIGNAL))
return -1;
encrypt_precompute(plain, temp_secret_key, con->shared_key);
con->status = TCP_STATUS_UNCONFIRMED;
return 1;
}
/* return 1 if connection handshake was handled correctly.
* return 0 if we didn't get it yet.
* return -1 if the connection must be killed.
*/
static int read_connection_handshake(TCP_Secure_Connection *con, const uint8_t *self_secret_key)
{
uint8_t data[TCP_CLIENT_HANDSHAKE_SIZE];
int len = 0;
if ((len = read_TCP_packet(con->sock, data, TCP_CLIENT_HANDSHAKE_SIZE)) != -1) {
return handle_TCP_handshake(con, data, len, self_secret_key);
}
return 0;
}
/* return 1 on success.
* return 0 if could not send packet.
* return -1 on failure (connection must be killed).
*/
static int send_routing_response(TCP_Secure_Connection *con, uint8_t rpid, const uint8_t *public_key)
{
uint8_t data[1 + 1 + crypto_box_PUBLICKEYBYTES];
data[0] = TCP_PACKET_ROUTING_RESPONSE;
data[1] = rpid;
memcpy(data + 2, public_key, crypto_box_PUBLICKEYBYTES);
return write_packet_TCP_secure_connection(con, data, sizeof(data));
}
/* return 1 on success.
* return 0 if could not send packet.
* return -1 on failure (connection must be killed).
*/
static int send_connect_notification(TCP_Secure_Connection *con, uint8_t id)
{
uint8_t data[2] = {TCP_PACKET_CONNECTION_NOTIFICATION, id + NUM_RESERVED_PORTS};
return write_packet_TCP_secure_connection(con, data, sizeof(data));
}
/* return 1 on success.
* return 0 if could not send packet.
* return -1 on failure (connection must be killed).
*/
static int send_disconnect_notification(TCP_Secure_Connection *con, uint8_t id)
{
uint8_t data[2] = {TCP_PACKET_DISCONNECT_NOTIFICATION, id + NUM_RESERVED_PORTS};
return write_packet_TCP_secure_connection(con, data, sizeof(data));
}
/* return 0 on success.
* return -1 on failure (connection must be killed).
*/
static int handle_TCP_routing_req(TCP_Server *TCP_server, uint32_t con_id, const uint8_t *public_key)
{
uint32_t i;
uint32_t index = ~0;
TCP_Secure_Connection *con = &TCP_server->accepted_connection_array[con_id];
/* If person tries to cennect to himself we deny the request*/
if (memcmp(con->public_key, public_key, crypto_box_PUBLICKEYBYTES) == 0) {
if (send_routing_response(con, 0, public_key) == -1)
return -1;
return 0;
}
for (i = 0; i < NUM_CLIENT_CONNECTIONS; ++i) {
if (con->connections[i].status != 0) {
if (memcmp(public_key, con->connections[i].public_key, crypto_box_PUBLICKEYBYTES) == 0) {
if (send_routing_response(con, i + NUM_RESERVED_PORTS, public_key) == -1) {
return -1;
} else {
return 0;
}
}
} else if (index == (uint32_t)~0) {
index = i;
}
}
if (index == (uint32_t)~0) {
if (send_routing_response(con, 0, public_key) == -1)
return -1;
return 0;
}
int ret = send_routing_response(con, index + NUM_RESERVED_PORTS, public_key);
if (ret == 0)
return 0;
if (ret == -1)
return -1;
con->connections[index].status = 1;
memcpy(con->connections[index].public_key, public_key, crypto_box_PUBLICKEYBYTES);
int other_index = get_TCP_connection_index(TCP_server, public_key);
if (other_index != -1) {
uint32_t other_id = ~0;
TCP_Secure_Connection *other_conn = &TCP_server->accepted_connection_array[other_index];
for (i = 0; i < NUM_CLIENT_CONNECTIONS; ++i) {
if (other_conn->connections[i].status == 1
&& memcmp(other_conn->connections[i].public_key, con->public_key, crypto_box_PUBLICKEYBYTES) == 0) {
other_id = i;
break;
}
}
if (other_id != (uint32_t)~0) {
con->connections[index].status = 2;
con->connections[index].index = other_index;
con->connections[index].other_id = other_id;
other_conn->connections[other_id].status = 2;
other_conn->connections[other_id].index = con_id;
other_conn->connections[other_id].other_id = index;
//TODO: return values?
send_connect_notification(con, index);
send_connect_notification(other_conn, other_id);
}
}
return 0;
}
/* return 0 on success.
* return -1 on failure (connection must be killed).
*/
static int handle_TCP_oob_send(TCP_Server *TCP_server, uint32_t con_id, const uint8_t *public_key, const uint8_t *data,
uint16_t length)
{
if (length == 0 || length > TCP_MAX_OOB_DATA_LENGTH)
return -1;
TCP_Secure_Connection *con = &TCP_server->accepted_connection_array[con_id];
int other_index = get_TCP_connection_index(TCP_server, public_key);
if (other_index != -1) {
uint8_t resp_packet[1 + crypto_box_PUBLICKEYBYTES + length];
resp_packet[0] = TCP_PACKET_OOB_RECV;
memcpy(resp_packet + 1, con->public_key, crypto_box_PUBLICKEYBYTES);
memcpy(resp_packet + 1 + crypto_box_PUBLICKEYBYTES, data, length);
write_packet_TCP_secure_connection(&TCP_server->accepted_connection_array[other_index], resp_packet,
sizeof(resp_packet));
}
return 0;
}
/* Remove connection with con_number from the connections array of con.
*
* return -1 on failure.
* return 0 on success.
*/
static int rm_connection_index(TCP_Server *TCP_server, TCP_Secure_Connection *con, uint8_t con_number)
{
if (con_number >= NUM_CLIENT_CONNECTIONS)
return -1;
if (con->connections[con_number].status) {
uint32_t index = con->connections[con_number].index;
uint8_t other_id = con->connections[con_number].other_id;
if (con->connections[con_number].status == 2) {
if (index >= TCP_server->size_accepted_connections)
return -1;
TCP_server->accepted_connection_array[index].connections[other_id].other_id = 0;
TCP_server->accepted_connection_array[index].connections[other_id].index = 0;
TCP_server->accepted_connection_array[index].connections[other_id].status = 1;
//TODO: return values?
send_disconnect_notification(&TCP_server->accepted_connection_array[index], other_id);
}
con->connections[con_number].index = 0;
con->connections[con_number].other_id = 0;
con->connections[con_number].status = 0;
return 0;
} else {
return -1;
}
}
static int handle_onion_recv_1(void *object, IP_Port dest, const uint8_t *data, uint16_t length)
{
TCP_Server *TCP_server = object;
uint32_t index = dest.ip.ip6.uint32[0];
if (index >= TCP_server->size_accepted_connections)
return 1;
TCP_Secure_Connection *con = &TCP_server->accepted_connection_array[index];
if (con->identifier != dest.ip.ip6.uint64[1])
return 1;
uint8_t packet[1 + length];
memcpy(packet + 1, data, length);
packet[0] = TCP_PACKET_ONION_RESPONSE;
if (write_packet_TCP_secure_connection(con, packet, sizeof(packet)) != 1)
return 1;
return 0;
}
/* return 0 on success
* return -1 on failure
*/
static int handle_TCP_packet(TCP_Server *TCP_server, uint32_t con_id, const uint8_t *data, uint16_t length)
{
if (length == 0)
return -1;
TCP_Secure_Connection *con = &TCP_server->accepted_connection_array[con_id];
switch (data[0]) {
case TCP_PACKET_ROUTING_REQUEST: {
if (length != 1 + crypto_box_PUBLICKEYBYTES)
return -1;
return handle_TCP_routing_req(TCP_server, con_id, data + 1);
}
case TCP_PACKET_CONNECTION_NOTIFICATION: {
if (length != 2)
return -1;
break;
}
case TCP_PACKET_DISCONNECT_NOTIFICATION: {
if (length != 2)
return -1;
return rm_connection_index(TCP_server, con, data[1] - NUM_RESERVED_PORTS);
}
case TCP_PACKET_PING: {
if (length != 1 + sizeof(uint64_t))
return -1;
uint8_t response[1 + sizeof(uint64_t)];
response[0] = TCP_PACKET_PONG;
memcpy(response + 1, data + 1, sizeof(uint64_t));
write_packet_TCP_secure_connection(con, response, sizeof(response));
return 0;
}
case TCP_PACKET_PONG: {
if (length != 1 + sizeof(uint64_t))
return -1;
uint64_t ping_id;
memcpy(&ping_id, data + 1, sizeof(uint64_t));
if (ping_id) {
if (ping_id == con->ping_id) {
con->ping_id = 0;
}
return 0;
} else {
return -1;
}
}
case TCP_PACKET_OOB_SEND: {
if (length <= 1 + crypto_box_PUBLICKEYBYTES)
return -1;
return handle_TCP_oob_send(TCP_server, con_id, data + 1, data + 1 + crypto_box_PUBLICKEYBYTES,
length - (1 + crypto_box_PUBLICKEYBYTES));
}
case TCP_PACKET_ONION_REQUEST: {
if (TCP_server->onion) {
if (length <= 1 + crypto_box_NONCEBYTES + ONION_SEND_BASE * 2)
return -1;
IP_Port source;
source.ip.family = TCP_ONION_FAMILY;
source.ip.ip6.uint32[0] = con_id;
source.ip.ip6.uint64[1] = con->identifier;
onion_send_1(TCP_server->onion, data + 1 + crypto_box_NONCEBYTES, length - (1 + crypto_box_NONCEBYTES), source,
data + 1);
}
return 0;
}
case TCP_PACKET_ONION_RESPONSE: {
return -1;
}
default: {
if (data[0] < NUM_RESERVED_PORTS)
return -1;
uint8_t c_id = data[0] - NUM_RESERVED_PORTS;
if (c_id >= NUM_CLIENT_CONNECTIONS)
return -1;
if (con->connections[c_id].status == 0)
return -1;
if (con->connections[c_id].status != 2)
return 0;
uint32_t index = con->connections[c_id].index;
uint8_t other_c_id = con->connections[c_id].other_id + NUM_RESERVED_PORTS;
uint8_t new_data[length];
memcpy(new_data, data, length);
new_data[0] = other_c_id;
int ret = write_packet_TCP_secure_connection(&TCP_server->accepted_connection_array[index], new_data, length);
if (ret == -1)
return -1;
return 0;
}
}
return 0;
}
static int confirm_TCP_connection(TCP_Server *TCP_server, TCP_Secure_Connection *con, const uint8_t *data,
uint16_t length)
{
int index = add_accepted(TCP_server, con);
if (index == -1)
return -1;
if (handle_TCP_packet(TCP_server, index, data, length) == -1) {
kill_accepted(TCP_server, index);
}
return index;
}
/* return 1 on success
* return 0 on failure
*/
static int accept_connection(TCP_Server *TCP_server, sock_t sock)
{
if (!sock_valid(sock))
return 0;
if (!set_socket_nonblock(sock)) {
kill_sock(sock);
return 0;
}
if (!set_socket_nosigpipe(sock)) {
kill_sock(sock);
return 0;
}
TCP_Secure_Connection *conn =
&TCP_server->incomming_connection_queue[TCP_server->incomming_connection_queue_index % MAX_INCOMMING_CONNECTIONS];
if (conn->status != TCP_STATUS_NO_STATUS)
kill_TCP_connection(conn);
conn->status = TCP_STATUS_CONNECTED;
conn->sock = sock;
conn->next_packet_length = 0;
++TCP_server->incomming_connection_queue_index;
return 1;
}
static sock_t new_listening_TCP_socket(int family, uint16_t port)
{
sock_t sock = socket(family, SOCK_STREAM, IPPROTO_TCP);
if (!sock_valid(sock)) {
return ~0;
}
#ifndef TCP_SERVER_USE_EPOLL
int ok = set_socket_nonblock(sock);
#else
int ok = 1;
#endif
if (ok && family == AF_INET6) {
ok = set_socket_dualstack(sock);
}
ok = ok && bind_to_port(sock, family, port) && (listen(sock, TCP_MAX_BACKLOG) == 0);
if (!ok) {
kill_sock(sock);
return ~0;
}
return sock;
}
TCP_Server *new_TCP_server(uint8_t ipv6_enabled, uint16_t num_sockets, const uint16_t *ports, const uint8_t *public_key,
const uint8_t *secret_key, Onion *onion)
{
if (num_sockets == 0 || ports == NULL)
return NULL;
if (networking_at_startup() != 0) {
return NULL;
}
TCP_Server *temp = calloc(1, sizeof(TCP_Server));
if (temp == NULL)
return NULL;
temp->socks_listening = calloc(num_sockets, sizeof(sock_t));
if (temp->socks_listening == NULL) {
free(temp);
return NULL;
}
#ifdef TCP_SERVER_USE_EPOLL
temp->efd = epoll_create1(0);
if (temp->efd == -1) {
free(temp);
return NULL;
}
#endif
uint8_t family;
if (ipv6_enabled) {
family = AF_INET6;
} else {
family = AF_INET;
}
uint32_t i;
#ifdef TCP_SERVER_USE_EPOLL
struct epoll_event ev;
#endif
for (i = 0; i < num_sockets; ++i) {
sock_t sock = new_listening_TCP_socket(family, ports[i]);
if (sock_valid(sock)) {
#ifdef TCP_SERVER_USE_EPOLL
ev.events = EPOLLIN;
ev.data.u64 = sock | ((uint64_t)TCP_SOCKET_LISTENING << 32);
if (epoll_ctl(temp->efd, EPOLL_CTL_ADD, sock, &ev) == -1) {
continue;
}
#endif
temp->socks_listening[temp->num_listening_socks] = sock;
++temp->num_listening_socks;
}
}
if (temp->num_listening_socks == 0) {
free(temp);
return NULL;
}
if (onion) {
temp->onion = onion;
set_callback_handle_recv_1(onion, &handle_onion_recv_1, temp);
}
memcpy(temp->public_key, public_key, crypto_box_PUBLICKEYBYTES);
memcpy(temp->secret_key, secret_key, crypto_box_SECRETKEYBYTES);
bs_list_init(&temp->accepted_key_list, crypto_box_PUBLICKEYBYTES, 8);
return temp;
}
static void do_TCP_accept_new(TCP_Server *TCP_server)
{
uint32_t i;
for (i = 0; i < TCP_server->num_listening_socks; ++i) {
struct sockaddr_storage addr;
unsigned int addrlen = sizeof(addr);
sock_t sock;
do {
sock = accept(TCP_server->socks_listening[i], (struct sockaddr *)&addr, &addrlen);
} while (accept_connection(TCP_server, sock));
}
}
static int do_incoming(TCP_Server *TCP_server, uint32_t i)
{
if (TCP_server->incomming_connection_queue[i].status != TCP_STATUS_CONNECTED)
return -1;
int ret = read_connection_handshake(&TCP_server->incomming_connection_queue[i], TCP_server->secret_key);
if (ret == -1) {
kill_TCP_connection(&TCP_server->incomming_connection_queue[i]);
} else if (ret == 1) {
int index_new = TCP_server->unconfirmed_connection_queue_index % MAX_INCOMMING_CONNECTIONS;
TCP_Secure_Connection *conn_old = &TCP_server->incomming_connection_queue[i];
TCP_Secure_Connection *conn_new = &TCP_server->unconfirmed_connection_queue[index_new];
if (conn_new->status != TCP_STATUS_NO_STATUS)
kill_TCP_connection(conn_new);
memcpy(conn_new, conn_old, sizeof(TCP_Secure_Connection));
memset(conn_old, 0, sizeof(TCP_Secure_Connection));
++TCP_server->unconfirmed_connection_queue_index;
return index_new;
}
return -1;
}
static int do_unconfirmed(TCP_Server *TCP_server, uint32_t i)
{
TCP_Secure_Connection *conn = &TCP_server->unconfirmed_connection_queue[i];
if (conn->status != TCP_STATUS_UNCONFIRMED)
return -1;
uint8_t packet[MAX_PACKET_SIZE];
int len = read_packet_TCP_secure_connection(conn->sock, &conn->next_packet_length, conn->shared_key, conn->recv_nonce,
packet, sizeof(packet));
if (len == 0) {
return -1;
} else if (len == -1) {
kill_TCP_connection(conn);
return -1;
} else {
int index_new;
if ((index_new = confirm_TCP_connection(TCP_server, conn, packet, len)) == -1) {
kill_TCP_connection(conn);
} else {
memset(conn, 0, sizeof(TCP_Secure_Connection));
}
return index_new;
}
}
static void do_confirmed_recv(TCP_Server *TCP_server, uint32_t i)
{
TCP_Secure_Connection *conn = &TCP_server->accepted_connection_array[i];
uint8_t packet[MAX_PACKET_SIZE];
int len;
while ((len = read_packet_TCP_secure_connection(conn->sock, &conn->next_packet_length, conn->shared_key,
conn->recv_nonce, packet, sizeof(packet)))) {
if (len == -1) {
kill_accepted(TCP_server, i);
break;
}
if (handle_TCP_packet(TCP_server, i, packet, len) == -1) {
kill_accepted(TCP_server, i);
break;
}
}
}
static void do_TCP_incomming(TCP_Server *TCP_server)
{
uint32_t i;
for (i = 0; i < MAX_INCOMMING_CONNECTIONS; ++i) {
do_incoming(TCP_server, i);
}
}
static void do_TCP_unconfirmed(TCP_Server *TCP_server)
{
uint32_t i;
for (i = 0; i < MAX_INCOMMING_CONNECTIONS; ++i) {
do_unconfirmed(TCP_server, i);
}
}
static void do_TCP_confirmed(TCP_Server *TCP_server)
{
#ifdef TCP_SERVER_USE_EPOLL
if (TCP_server->last_run_pinged == unix_time())
return;
TCP_server->last_run_pinged = unix_time();
#endif
uint32_t i;
for (i = 0; i < TCP_server->size_accepted_connections; ++i) {
TCP_Secure_Connection *conn = &TCP_server->accepted_connection_array[i];
if (conn->status != TCP_STATUS_CONFIRMED)
continue;
if (is_timeout(conn->last_pinged, TCP_PING_FREQUENCY)) {
uint8_t ping[1 + sizeof(uint64_t)];
ping[0] = TCP_PACKET_PING;
uint64_t ping_id = random_64b();
if (!ping_id)
++ping_id;
memcpy(ping + 1, &ping_id, sizeof(uint64_t));
int ret = write_packet_TCP_secure_connection(conn, ping, sizeof(ping));
if (ret == 1) {
conn->last_pinged = unix_time();
conn->ping_id = ping_id;
} else {
if (is_timeout(conn->last_pinged, TCP_PING_FREQUENCY + TCP_PING_TIMEOUT)) {
kill_accepted(TCP_server, i);
continue;
}
}
}
if (conn->ping_id && is_timeout(conn->last_pinged, TCP_PING_TIMEOUT)) {
kill_accepted(TCP_server, i);
continue;
}
send_pending_data(conn);
#ifndef TCP_SERVER_USE_EPOLL
do_confirmed_recv(TCP_server, i);
#endif
}
}
#ifdef TCP_SERVER_USE_EPOLL
static void do_TCP_epoll(TCP_Server *TCP_server)
{
#define MAX_EVENTS 16
struct epoll_event events[MAX_EVENTS];
int nfds;
while ((nfds = epoll_wait(TCP_server->efd, events, MAX_EVENTS, 0)) > 0) {
int n;
for (n = 0; n < nfds; ++n) {
sock_t sock = events[n].data.u64 & 0xFFFFFFFF;
int status = (events[n].data.u64 >> 32) & 0xFFFF, index = (events[n].data.u64 >> 48);
if ((events[n].events & EPOLLERR) || (events[n].events & EPOLLHUP)) {
switch (status) {
case TCP_SOCKET_LISTENING: {
//should never happen
break;
}
case TCP_SOCKET_INCOMING: {
kill_TCP_connection(&TCP_server->incomming_connection_queue[index]);
break;
}
case TCP_SOCKET_UNCONFIRMED: {
kill_TCP_connection(&TCP_server->unconfirmed_connection_queue[index]);
break;
}
case TCP_SOCKET_CONFIRMED: {
kill_accepted(TCP_server, index);
break;
}
}
continue;
}
if (!(events[n].events & EPOLLIN)) {
continue;
}
switch (status) {
case TCP_SOCKET_LISTENING: {
//socket is from socks_listening, accept connection
struct sockaddr_storage addr;
unsigned int addrlen = sizeof(addr);
sock_t sock_new;
sock_new = accept(sock, (struct sockaddr *)&addr, &addrlen);
int index_new = TCP_server->incomming_connection_queue_index % MAX_INCOMMING_CONNECTIONS;
if (!accept_connection(TCP_server, sock_new)) {
break;
}
struct epoll_event ev = {
.events = EPOLLIN | EPOLLET,
.data.u64 = sock_new | ((uint64_t)TCP_SOCKET_INCOMING << 32) | ((uint64_t)index_new << 48)
};
if (epoll_ctl(TCP_server->efd, EPOLL_CTL_ADD, sock_new, &ev) == -1) {
kill_TCP_connection(&TCP_server->incomming_connection_queue[index_new]);
break;
}
break;
}
case TCP_SOCKET_INCOMING: {
int index_new;
if ((index_new = do_incoming(TCP_server, index)) != -1) {
events[n].events = EPOLLIN | EPOLLET;
events[n].data.u64 = sock | ((uint64_t)TCP_SOCKET_UNCONFIRMED << 32) | ((uint64_t)index_new << 48);
if (epoll_ctl(TCP_server->efd, EPOLL_CTL_MOD, sock, &events[n]) == -1) {
kill_TCP_connection(&TCP_server->unconfirmed_connection_queue[index_new]);
break;
}
}
break;
}
case TCP_SOCKET_UNCONFIRMED: {
int index_new;
if ((index_new = do_unconfirmed(TCP_server, index)) != -1) {
events[n].events = EPOLLIN | EPOLLET;
events[n].data.u64 = sock | ((uint64_t)TCP_SOCKET_CONFIRMED << 32) | ((uint64_t)index_new << 48);
if (epoll_ctl(TCP_server->efd, EPOLL_CTL_MOD, sock, &events[n]) == -1) {
//remove from confirmed connections
kill_accepted(TCP_server, index_new);
break;
}
}
break;
}
case TCP_SOCKET_CONFIRMED: {
do_confirmed_recv(TCP_server, index);
break;
}
}
}
}
#undef MAX_EVENTS
}
#endif
void do_TCP_server(TCP_Server *TCP_server)
{
unix_time_update();
#ifdef TCP_SERVER_USE_EPOLL
do_TCP_epoll(TCP_server);
#else
do_TCP_accept_new(TCP_server);
do_TCP_incomming(TCP_server);
do_TCP_unconfirmed(TCP_server);
#endif
do_TCP_confirmed(TCP_server);
}
void kill_TCP_server(TCP_Server *TCP_server)
{
uint32_t i;
for (i = 0; i < TCP_server->num_listening_socks; ++i) {
kill_sock(TCP_server->socks_listening[i]);
}
if (TCP_server->onion) {
set_callback_handle_recv_1(TCP_server->onion, NULL, NULL);
}
bs_list_free(&TCP_server->accepted_key_list);
#ifdef TCP_SERVER_USE_EPOLL
close(TCP_server->efd);
#endif
free(TCP_server->socks_listening);
free(TCP_server);
}