/* * 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(TCP_Server *TCP_server, uint8_t *public_key) { return 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, 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 (!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 (!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, 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, 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, uint8_t *data, uint16_t length, 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, 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, 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, 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, uint8_t *public_key, 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, 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, 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, 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 0; } /* 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; } int ok = set_socket_nonblock(sock); 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, uint16_t *ports, uint8_t *public_key, 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; } uint8_t family; if (ipv6_enabled) { family = AF_INET6; } else { family = AF_INET; } uint32_t i; for (i = 0; i < num_sockets; ++i) { sock_t sock = new_listening_TCP_socket(family, ports[i]); if (sock_valid(sock)) { 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); list_init(&temp->accepted_key_list, crypto_box_PUBLICKEYBYTES); 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 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 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_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; } 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); 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; } } } } void do_TCP_server(TCP_Server *TCP_server) { unix_time_update(); do_TCP_accept_new(TCP_server); do_TCP_incomming(TCP_server); do_TCP_unconfirmed(TCP_server); 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); } list_free(&TCP_server->accepted_key_list); free(TCP_server->socks_listening); free(TCP_server); }