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_TCP_incomming(TCP_Server *TCP_server)
{
uint32_t i;
for (i = 0; i < MAX_INCOMMING_CONNECTIONS; ++i) {
if (TCP_server->incomming_connection_queue[i].status != TCP_STATUS_CONNECTED)
continue;
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) {
TCP_Secure_Connection *conn_old = &TCP_server->incomming_connection_queue[i];
TCP_Secure_Connection *conn_new =
&TCP_server->unconfirmed_connection_queue[TCP_server->unconfirmed_connection_queue_index % MAX_INCOMMING_CONNECTIONS];
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;
}
}
}
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 void do_TCP_unconfirmed(TCP_Server *TCP_server)
{
uint32_t i;
for (i = 0; i < MAX_INCOMMING_CONNECTIONS; ++i) {
TCP_Secure_Connection *conn = &TCP_server->unconfirmed_connection_queue[i];
if (conn->status != TCP_STATUS_UNCONFIRMED)
continue;
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) {
continue;
} else if (len == -1) {
kill_TCP_connection(conn);
continue;
} else {
if (confirm_TCP_connection(TCP_server, conn, packet, len) == -1) {
kill_TCP_connection(conn);
} else {
memset(conn, 0, sizeof(TCP_Secure_Connection));
}
}
}
}
static void do_TCP_unconfirmed(TCP_Server *TCP_server)
{
uint32_t i;
for (i = 0; i < MAX_INCOMMING_CONNECTIONS; ++i) {
TCP_Secure_Connection *conn = &TCP_server->unconfirmed_connection_queue[i];
if (conn->status != TCP_STATUS_UNCONFIRMED)
continue;
uint8_t packet[MAX_PACKET_SIZE];
int len = read_packet_TCP_secure_connection(conn, packet, sizeof(packet));
if (len == 0) {
continue;
} else if (len == -1) {
kill_TCP_connection(conn);
continue;
} else {
//TODO
confirm_TCP_connection(conn, packet, len);
kill_TCP_connection(conn);
}
}
}
static void do_TCP_confirmed(TCP_Server *TCP_server)
{
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;
}
}
if (conn->ping_id && is_timeout(conn->last_pinged, TCP_PING_TIMEOUT)) {
kill_TCP_connection(conn);
del_accepted(TCP_server, i);
continue;
}
send_pending_data(conn);
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_TCP_connection(conn);
del_accepted(TCP_server, i);
break;
}
if (handle_TCP_packet(TCP_server, i, packet, len) == -1) {
kill_TCP_connection(conn);
del_accepted(TCP_server, i);
break;
}
}
}
}
/* 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;
}
/* 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);
}
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);
}
static int confirm_TCP_connection(TCP_Server *TCP_server, TCP_Secure_Connection *con, uint8_t *data, uint16_t length)
{
int index = add_accepted(TCP_server, con);
if (index == -1)
return -1;
TCP_Secure_Connection *conn = &TCP_server->accepted_connection_array[index];
if (handle_TCP_packet(TCP_server, index, data, length) == -1) {
kill_TCP_connection(conn);
del_accepted(TCP_server, index);
}
return 0;
}
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_ip_port(tcp_con->connection);
uint8_t relay_pk[CRYPTO_PUBLIC_KEY_SIZE];
memcpy(relay_pk, tcp_con_public_key(tcp_con->connection), CRYPTO_PUBLIC_KEY_SIZE);
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_ip_port(tcp_con->connection);
memcpy(tcp_con->relay_pk, tcp_con_public_key(tcp_con->connection), CRYPTO_PUBLIC_KEY_SIZE);
kill_TCP_connection(tcp_con->connection);
tcp_con->connection = nullptr;
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 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) {
kill_TCP_connection(con);
return -1;
}
sodium_memzero(con, sizeof(TCP_Secure_Connection));
if (handle_TCP_packet(TCP_server, index, data, length) == -1) {
kill_accepted(TCP_server, index);
return -1;
}
return index;
}
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);
}