/* group_chats.c * * An implementation of massive text only group chats. * * * Copyright (C) 2013 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 "DHT.h" #include "assoc.h" #include "group_chats.h" #include "LAN_discovery.h" #include "util.h" #define GROUPCHAT_MAXDATA_LENGTH (MAX_CRYPTO_REQUEST_SIZE - (1 + crypto_box_PUBLICKEYBYTES * 2 + crypto_box_NONCEBYTES)) #define GROUPCHAT_MAXPLAINDATA_LENGTH (GROUPCHAT_MAXDATA_LENGTH - crypto_box_MACBYTES) #define GROUP_MAX_SENDNODES (GROUP_CLOSE_CONNECTIONS * 2) typedef struct { uint64_t pingid; //uint8_t client_id[crypto_box_PUBLICKEYBYTES]; } getnodes_data; typedef struct { uint8_t client_id[crypto_box_PUBLICKEYBYTES]; IP_Port ip_port; } groupchat_nodes; typedef struct { uint64_t pingid; groupchat_nodes nodes[GROUP_CLOSE_CONNECTIONS]; //uint8_t client_id[crypto_box_PUBLICKEYBYTES]; } sendnodes_data; /* * check if peer with client_id is in peer array. * * return peer number if peer is in chat. * return -1 if peer is not in chat. * * TODO: make this more efficient. */ static int peer_in_chat(Group_Chat *chat, uint8_t *client_id) { uint32_t i; for (i = 0; i < chat->numpeers; ++i) if (id_equal(chat->group[i].client_id, client_id)) return i; return -1; } /* Compares client_id1 and client_id2 with client_id. * * return 0 if both are same distance. * return 1 if client_id1 is closer. * return 2 if client_id2 is closer. */ static int id_closest_groupchats(uint8_t *id, uint8_t *id1, uint8_t *id2) { size_t i; uint8_t distance1, distance2; for (i = 0; i < CLIENT_ID_SIZE; ++i) { distance1 = abs(((int8_t *)id)[i] - ((int8_t *)id1)[i]); distance2 = abs(((int8_t *)id)[i] - ((int8_t *)id2)[i]); if (distance1 < distance2) return 1; if (distance1 > distance2) return 2; } return 0; } #define BAD_GROUPNODE_TIMEOUT 30 /* * Check if peer is closer to us that the other peers in the list and if the peer is in the list. * Return the number of peers it is closer to if it is not in the closelist. * Return -1 if the peer is in the closelist. */ static int peer_okping(Group_Chat *chat, uint8_t *client_id) { uint32_t i, j = 0; if (id_equal(chat->self_public_key, client_id)) return -1; for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { if (is_timeout(chat->close[i].last_recv, BAD_GROUPNODE_TIMEOUT)) { ++j; continue; } /* Equal */ if (id_equal(chat->close[i].client_id, client_id)) return -1; if (id_closest_groupchats(chat->self_public_key, chat->close[i].client_id, client_id) == 2) ++j; } return j; } /* Attempt to add a peer to the close list. * Update last_recv if it is in list. * Attempt to add it to list if it is not. * * Return 0 if success. * Return -1 if peer was not put in list/updated. */ static int add_closepeer(Group_Chat *chat, uint8_t *client_id, IP_Port ip_port) { uint32_t i; for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { /* Check if node is already in list, if it is update its last_recv */ if (id_equal(chat->close[i].client_id, client_id)) { chat->close[i].last_recv = unix_time(); return 0; } } for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { /* Try replacing bad nodes first */ if (is_timeout(chat->close[i].last_recv, BAD_GROUPNODE_TIMEOUT)) { id_copy(chat->close[i].client_id, client_id); chat->close[i].ip_port = ip_port; chat->close[i].last_recv = unix_time(); return 0; } } for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { /* Replace nodes if given one is closer. */ if (id_closest_groupchats(chat->self_public_key, chat->close[i].client_id, client_id) == 2) { id_copy(chat->close[i].client_id, client_id); chat->close[i].ip_port = ip_port; chat->close[i].last_recv = unix_time(); return 0; } } return -1; } static int send_groupchatpacket(Group_Chat *chat, IP_Port ip_port, uint8_t *public_key, uint8_t *data, uint32_t length, uint8_t request_id) { if (id_equal(chat->self_public_key, public_key)) return -1; uint8_t packet[MAX_CRYPTO_REQUEST_SIZE]; int len = create_request(chat->self_public_key, chat->self_secret_key, packet, public_key, data, length, request_id); packet[0] = NET_PACKET_GROUP_CHATS; if (len == -1) return -1; if (sendpacket(chat->net, ip_port, packet, len) == len) return 0; return -1; } /* * Send data to all peers in close peer list. * * return the number of peers the packet was sent to. */ static uint8_t sendto_allpeers(Group_Chat *chat, uint8_t *data, uint16_t length, uint8_t request_id) { uint16_t sent = 0; uint32_t i; for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { if (ip_isset(&chat->close[i].ip_port.ip) && !is_timeout(chat->close[i].last_recv, BAD_GROUPNODE_TIMEOUT)) { if (send_groupchatpacket(chat, chat->close[i].ip_port, chat->close[i].client_id, data, length, request_id) == 0) ++sent; } } return sent; } /* * Add a peer to the group chat. * * return peernum if success or peer already in chat. * return -1 if error. */ static int addpeer(Group_Chat *chat, uint8_t *client_id) { int peernum = peer_in_chat(chat, client_id); if (peernum != -1) return peernum; Group_Peer *temp; temp = realloc(chat->group, sizeof(Group_Peer) * (chat->numpeers + 1)); if (temp == NULL) return -1; memset(&(temp[chat->numpeers]), 0, sizeof(Group_Peer)); chat->group = temp; id_copy(chat->group[chat->numpeers].client_id, client_id); chat->group[chat->numpeers].last_recv = unix_time(); chat->group[chat->numpeers].last_recv_msgping = unix_time(); ++chat->numpeers; if (chat->peer_namelistchange != NULL) (*chat->peer_namelistchange)(chat, chat->numpeers - 1, CHAT_CHANGE_PEER_ADD, chat->group_namelistchange_userdata); return (chat->numpeers - 1); } /* * Set a peer from the group chat to deleted. * * return 0 if success * return -1 if error. */ static int del_peer_set(Group_Chat *chat, int peernum) { if ((uint32_t)peernum >= chat->numpeers) return -1; chat->group[peernum].deleted = 1; chat->group[peernum].deleted_time = unix_time(); return 0; } /* * Delete a peer from the group chat. * * return 0 if success * return -1 if error. */ static int delpeer(Group_Chat *chat, int peernum) { if ((uint32_t)peernum >= chat->numpeers) return -1; uint32_t i; for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { /* If peer is in close list, time it out forcefully. */ if (id_equal(chat->close[i].client_id, chat->group[peernum].client_id)) { chat->close[i].last_recv = 0; break; } } Group_Peer *temp; --chat->numpeers; if (chat->numpeers == 0) { free(chat->group); chat->group = NULL; return 0; } if (chat->numpeers != (uint32_t)peernum) memcpy(&chat->group[peernum], &chat->group[chat->numpeers], sizeof(Group_Peer)); temp = realloc(chat->group, sizeof(Group_Peer) * (chat->numpeers)); if (temp == NULL) return -1; chat->group = temp; if (chat->peer_namelistchange != NULL) { (*chat->peer_namelistchange)(chat, peernum, CHAT_CHANGE_PEER_DEL, chat->group_namelistchange_userdata); } return 0; } /* Copy the name of peernum to name. * name must be at least MAX_NICK_BYTES long. * * return length of name if success * return -1 if failure */ int group_peername(Group_Chat *chat, int peernum, uint8_t *name) { if ((uint32_t)peernum >= chat->numpeers) return -1; if (chat->group[peernum].nick_len == 0) { /* memcpy(name, "NSA agent", 10); */ /* Srsly? */ /* Kindly remind the user that someone with no name might be a moronic NSA agent.*/ name[0] = 0; return 0; } memcpy(name, chat->group[peernum].nick, chat->group[peernum].nick_len); return chat->group[peernum].nick_len; } static void setnick(Group_Chat *chat, int peernum, uint8_t *contents, uint16_t contents_len) { if (contents_len > MAX_NICK_BYTES || contents_len == 0) return; /* same name as already stored? */ if (chat->group[peernum].nick_len == contents_len) if (!memcmp(chat->group[peernum].nick, contents, contents_len)) return; memcpy(chat->group[peernum].nick, contents, contents_len); chat->group[peernum].nick_len = contents_len; if (chat->peer_namelistchange != NULL) (*chat->peer_namelistchange)(chat, peernum, CHAT_CHANGE_PEER_NAME, chat->group_namelistchange_userdata); } /* min time between pings sent to one peer in seconds */ /* TODO: move this to global section */ #define GROUP_PING_TIMEOUT 5 static int send_getnodes(Group_Chat *chat, IP_Port ip_port, int peernum) { if ((uint32_t)peernum >= chat->numpeers) return -1; if (!is_timeout(chat->group[peernum].last_pinged, GROUP_PING_TIMEOUT)) return -1; getnodes_data contents; contents.pingid = random_64b(); chat->group[peernum].last_pinged = unix_time(); chat->group[peernum].pingid = contents.pingid; chat->group[peernum].ping_via = ip_port; if (chat->assoc) { IPPTs ippts; ippts.timestamp = unix_time(); ippts.ip_port = ip_port; Assoc_add_entry(chat->assoc, chat->group[peernum].client_id, &ippts, NULL, 1); } return send_groupchatpacket(chat, ip_port, chat->group[peernum].client_id, (uint8_t *)&contents, sizeof(contents), CRYPTO_PACKET_GROUP_CHAT_GET_NODES); } static int send_sendnodes(Group_Chat *chat, IP_Port ip_port, int peernum, uint64_t pingid) { if ((uint32_t)peernum >= chat->numpeers) return -1; sendnodes_data contents; contents.pingid = pingid; uint32_t i, j = 0; for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { if (!is_timeout(chat->close[i].last_recv, BAD_GROUPNODE_TIMEOUT)) { id_copy(contents.nodes[j].client_id, chat->close[i].client_id); contents.nodes[j].ip_port = chat->close[i].ip_port; to_net_family(&contents.nodes[j].ip_port.ip); ++j; } } return send_groupchatpacket(chat, ip_port, chat->group[peernum].client_id, (uint8_t *)&contents, sizeof(contents.pingid) + sizeof(groupchat_nodes) * j, CRYPTO_PACKET_GROUP_CHAT_SEND_NODES); } static int handle_getnodes(Group_Chat *chat, IP_Port source, int peernum, uint8_t *data, uint32_t len) { if (len != sizeof(getnodes_data)) return 1; if ((uint32_t)peernum >= chat->numpeers) return 1; getnodes_data contents; memcpy(&contents, data, sizeof(contents)); send_sendnodes(chat, source, peernum, contents.pingid); if (peer_okping(chat, chat->group[peernum].client_id) > 0) send_getnodes(chat, source, peernum); return 0; } static int handle_sendnodes(Group_Chat *chat, IP_Port source, int peernum, uint8_t *data, uint32_t len) { if ((uint32_t)peernum >= chat->numpeers) return 1; if (len > sizeof(sendnodes_data) || len < sizeof(uint64_t)) return 1; if ((len - sizeof(uint64_t)) % sizeof(groupchat_nodes) != 0) return 1; if (is_timeout(chat->group[peernum].last_pinged, GROUP_PING_TIMEOUT)) return 1; sendnodes_data contents; memcpy(&contents, data, len); if (contents.pingid != chat->group[peernum].pingid) return 1; uint16_t numnodes = (len - sizeof(contents.pingid)) / sizeof(groupchat_nodes); uint32_t i; IPPTs ippts_send; ippts_send.timestamp = unix_time(); for (i = 0; i < numnodes; ++i) { if (peer_okping(chat, contents.nodes[i].client_id) > 0) { int peern = peer_in_chat(chat, contents.nodes[i].client_id); if (peern == -1) { /*NOTE: This is just for testing and will be removed later.*/ peern = addpeer(chat, contents.nodes[i].client_id); } if (peern == -1) continue; to_host_family(&contents.nodes[i].ip_port.ip); send_getnodes(chat, contents.nodes[i].ip_port, peern); if (chat->assoc) { ippts_send.ip_port = contents.nodes[i].ip_port; Assoc_add_entry(chat->assoc, contents.nodes[i].client_id, &ippts_send, NULL, 0); } } } int ok = add_closepeer(chat, chat->group[peernum].client_id, source); if (chat->assoc) { ippts_send.ip_port = chat->group[peernum].ping_via; ippts_send.timestamp = chat->group[peernum].last_pinged; IP_Port ipp_recv; ipp_recv = source; Assoc_add_entry(chat->assoc, contents.nodes[i].client_id, &ippts_send, &ipp_recv, ok == 0 ? 1 : 0); } return 0; } #define GROUP_DATA_MIN_SIZE (crypto_box_PUBLICKEYBYTES + sizeof(uint32_t) + 1) static void send_names_new_peer(Group_Chat *chat); static int handle_data(Group_Chat *chat, uint8_t *data, uint32_t len) { if (len < GROUP_DATA_MIN_SIZE) return 1; //TODO: int peernum = peer_in_chat(chat, data); if (peernum == -1) { /*NOTE: This is just for testing and will be removed later.*/ if (data[crypto_box_PUBLICKEYBYTES + sizeof(uint32_t)] != GROUP_CHAT_QUIT) peernum = addpeer(chat, data); } if (peernum == -1) return 1; if (chat->group[peernum].deleted) return 1; /* Spam prevention (1 message per peer per second limit.) if (chat->group[peernum].last_recv == temp_time) return 1; */ chat->group[peernum].last_recv = unix_time(); uint32_t message_num; memcpy(&message_num, data + crypto_box_PUBLICKEYBYTES, sizeof(uint32_t)); message_num = ntohl(message_num); if (chat->group[peernum].last_message_number == 0) { chat->group[peernum].last_message_number = message_num; } else if (message_num - chat->group[peernum].last_message_number > 64 || message_num == chat->group[peernum].last_message_number) return 1; chat->group[peernum].last_message_number = message_num; int handled = 1; uint8_t *contents = data + GROUP_DATA_MIN_SIZE; uint16_t contents_len = len - GROUP_DATA_MIN_SIZE; switch (data[crypto_box_PUBLICKEYBYTES + sizeof(message_num)]) { case GROUP_CHAT_PING: /* If message is ping */ if (contents_len != 0) return 1; chat->group[peernum].last_recv_msgping = unix_time(); break; case GROUP_CHAT_NEW_PEER: /* If message is new peer */ if (contents_len != crypto_box_PUBLICKEYBYTES) return 1; addpeer(chat, contents); send_names_new_peer(chat); break; case GROUP_CHAT_QUIT: /* If peer tells us he is quitting */ if (contents_len != 0) return 1; del_peer_set(chat, peernum); break; case GROUP_CHAT_PEER_NICK: if (contents_len > MAX_NICK_BYTES || contents_len == 0) return 1; setnick(chat, peernum, contents, contents_len); break; case GROUP_CHAT_CHAT_MESSAGE: /* If message is chat message */ if (chat->group_message != NULL) (*chat->group_message)(chat, peernum, contents, contents_len, chat->group_message_userdata); break; case GROUP_CHAT_ACTION: /* if message is a peer action */ if (chat->group_action != NULL) (*chat->group_action)(chat, peernum, contents, contents_len, chat->group_action_userdata); break; default: handled = 0; break; } if (handled == 1) { sendto_allpeers(chat, data, len, CRYPTO_PACKET_GROUP_CHAT_BROADCAST); return 0; } return 1; } static uint8_t send_data(Group_Chat *chat, uint8_t *data, uint32_t len, uint8_t message_id) { if (len + GROUP_DATA_MIN_SIZE > MAX_CRYPTO_REQUEST_SIZE) /*NOTE: not the real maximum len.*/ return 1; uint8_t packet[MAX_CRYPTO_REQUEST_SIZE]; ++chat->message_number; if (chat->message_number == 0) chat->message_number = 1; uint32_t message_num = htonl(chat->message_number); //TODO id_copy(packet, chat->self_public_key); memcpy(packet + crypto_box_PUBLICKEYBYTES, &message_num, sizeof(message_num)); if (len != 0) memcpy(packet + GROUP_DATA_MIN_SIZE, data, len); packet[crypto_box_PUBLICKEYBYTES + sizeof(message_num)] = message_id; return sendto_allpeers(chat, packet, len + GROUP_DATA_MIN_SIZE, CRYPTO_PACKET_GROUP_CHAT_BROADCAST); } /* * Handle get nodes group packet. * * return 0 if handled correctly. * return 1 if error. */ int handle_groupchatpacket(Group_Chat *chat, IP_Port source, uint8_t *packet, uint32_t length) { if (length > MAX_CRYPTO_REQUEST_SIZE) return 1; uint8_t public_key[crypto_box_PUBLICKEYBYTES]; uint8_t data[MAX_CRYPTO_REQUEST_SIZE]; uint8_t number; int len = handle_request(chat->self_public_key, chat->self_secret_key, public_key, data, &number, packet, length); if (len <= 0) return 1; if (id_equal(chat->self_public_key, public_key)) return 1; int peernum = peer_in_chat(chat, public_key); if (peernum == -1) return 1; switch (number) { case CRYPTO_PACKET_GROUP_CHAT_GET_NODES: return handle_getnodes(chat, source, peernum, data, len); case CRYPTO_PACKET_GROUP_CHAT_SEND_NODES: return handle_sendnodes(chat, source, peernum, data, len); case CRYPTO_PACKET_GROUP_CHAT_BROADCAST: return handle_data(chat, data, len); default: return 1; } return 1; } uint32_t group_sendmessage(Group_Chat *chat, uint8_t *message, uint32_t length) { return send_data(chat, message, length, GROUP_CHAT_CHAT_MESSAGE); //TODO: better return values? } uint32_t group_sendaction(Group_Chat *chat, uint8_t *action, uint32_t length) { return send_data(chat, action, length, GROUP_CHAT_ACTION); } /* * Send id/nick combo to the group. * * returns the number of peers it has sent it to. */ static uint32_t group_send_nick(Group_Chat *chat, uint8_t *nick, uint16_t nick_len) { if (nick_len > MAX_NICK_BYTES) return 0; return send_data(chat, nick, nick_len, GROUP_CHAT_PEER_NICK); } int set_nick(Group_Chat *chat, uint8_t *nick, uint16_t nick_len) { if (nick_len > MAX_NICK_BYTES || nick_len == 0) return -1; memcpy(chat->nick, nick, nick_len); chat->nick_len = nick_len; group_send_nick(chat, chat->nick, chat->nick_len); return 0; } uint32_t group_newpeer(Group_Chat *chat, uint8_t *client_id) { addpeer(chat, client_id); return send_data(chat, client_id, crypto_box_PUBLICKEYBYTES, GROUP_CHAT_NEW_PEER); //TODO: better return values? } void callback_groupmessage(Group_Chat *chat, void (*function)(Group_Chat *chat, int, uint8_t *, uint16_t, void *), void *userdata) { chat->group_message = function; chat->group_message_userdata = userdata; } void callback_groupaction(Group_Chat *chat, void (*function)(Group_Chat *chat, int, uint8_t *, uint16_t, void *), void *userdata) { chat->group_action = function; chat->group_action_userdata = userdata; } void callback_namelistchange(Group_Chat *chat, void (*function)(Group_Chat *chat, int peer, uint8_t change, void *), void *userdata) { chat->peer_namelistchange = function; chat->group_namelistchange_userdata = userdata; } uint32_t group_numpeers(Group_Chat *chat) { return chat->numpeers; } uint32_t group_client_names(Group_Chat *chat, uint8_t names[][MAX_NICK_BYTES], uint16_t lengths[], uint16_t length) { uint32_t i; for (i = 0; i < chat->numpeers && i < length; ++i) { lengths[i] = group_peername(chat, i, names[i]); } return i; } Group_Chat *new_groupchat(Networking_Core *net) { unix_time_update(); if (net == 0) return 0; Group_Chat *chat = calloc(1, sizeof(Group_Chat)); chat->net = net; crypto_box_keypair(chat->self_public_key, chat->self_secret_key); /* (2^4) * 5 = 80 entries seems to be a moderate size */ chat->assoc = new_Assoc(4, 5, chat->self_public_key); return chat; } #define NODE_PING_INTERVAL 10 static void ping_close(Group_Chat *chat) { uint32_t i; for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { if (!is_timeout(chat->close[i].last_recv, BAD_GROUPNODE_TIMEOUT)) { int peernum = peer_in_chat(chat, chat->close[i].client_id); if (peernum == -1) continue; if (is_timeout(chat->group[peernum].last_pinged, NODE_PING_INTERVAL)) send_getnodes(chat, chat->close[i].ip_port, peernum); } } } /* Interval in seconds to send ping messages */ #define GROUP_PING_INTERVAL 30 static void ping_group(Group_Chat *chat) { if (is_timeout(chat->last_sent_ping, GROUP_PING_INTERVAL)) { if (send_data(chat, 0, 0, GROUP_CHAT_PING) != 0) /* Ping */ chat->last_sent_ping = unix_time(); } } #define DEL_PEER_DELAY 3 static void del_dead_peers(Group_Chat *chat) { uint32_t i; for (i = 0; i < chat->numpeers; ++i) { if (is_timeout(chat->group[i].last_recv_msgping, GROUP_PING_INTERVAL * 4)) { delpeer(chat, i); } if (chat->group == NULL || i >= chat->numpeers) break; if (chat->group[i].deleted) { if (is_timeout(chat->group[i].deleted_time, DEL_PEER_DELAY)) delpeer(chat, i); } } } #define NICK_SEND_INTERVAL 180 static void send_names_new_peer(Group_Chat *chat) { group_send_nick(chat, chat->nick, chat->nick_len); chat->last_sent_nick = (unix_time() - NICK_SEND_INTERVAL) + 15; } static void send_names(Group_Chat *chat) { /* send own nick from time to time, to let newly added peers be informed * first time only: use a shorter timeframe, because we might not be in our own * peer list yet */ if (is_timeout(chat->last_sent_nick, 180)) if (group_send_nick(chat, chat->nick, chat->nick_len) > 0) { if (!chat->last_sent_nick) chat->last_sent_nick = (unix_time() - NICK_SEND_INTERVAL) + 10; else chat->last_sent_nick = unix_time(); } } void do_groupchat(Group_Chat *chat) { unix_time_update(); ping_close(chat); ping_group(chat); /* TODO: Maybe run this less? */ del_dead_peers(chat); send_names(chat); } void kill_groupchat(Group_Chat *chat) { send_data(chat, 0, 0, GROUP_CHAT_QUIT); free(chat->group); free(chat); } void chat_bootstrap(Group_Chat *chat, IP_Port ip_port, uint8_t *client_id) { send_getnodes(chat, ip_port, addpeer(chat, client_id)); } void chat_bootstrap_nonlazy(Group_Chat *chat, IP_Port ip_port, uint8_t *client_id) { send_getnodes(chat, ip_port, addpeer(chat, client_id)); add_closepeer(chat, client_id, ip_port); }