/* SPDX-License-Identifier: GPL-3.0-or-later * Copyright © 2016-2020 The TokTok team. * Copyright © 2015 Tox project. */ /** * An implementation of massive text only group chats. */ #ifndef GROUP_CHATS_H #define GROUP_CHATS_H #include #include #include "TCP_connection.h" #include "bin_pack.h" #include "bin_unpack.h" #include "group_announce.h" #include "group_common.h" #include "group_connection.h" #include "logger.h" #define GC_PING_TIMEOUT 12 #define GC_SEND_IP_PORT_INTERVAL (GC_PING_TIMEOUT * 5) #define GC_CONFIRMED_PEER_TIMEOUT (GC_PING_TIMEOUT * 4 + 10) #define GC_UNCONFIRMED_PEER_TIMEOUT GC_PING_TIMEOUT #define GC_JOIN_DATA_LENGTH (ENC_PUBLIC_KEY_SIZE + CHAT_ID_SIZE) /** Group topic lock states. */ typedef enum Group_Topic_Lock { TL_ENABLED = 0x00, // Only the Founder and moderators may set the topic TL_DISABLED = 0x01, // Anyone except Observers may set the topic } Group_Topic_Lock; /** Group moderation events. */ typedef enum Group_Moderation_Event { MV_KICK = 0x00, // A peer has been kicked MV_OBSERVER = 0x01, // A peer has been demoted to Observer MV_USER = 0x02, // A peer has been demoted or promoted to User MV_MOD = 0x03, // A peer has been promoted to or demoted from Moderator } Group_Moderation_Event; /** Messenger level group invite types */ typedef enum Group_Invite_Message_Type { GROUP_INVITE = 0x00, // Peer has initiated an invite GROUP_INVITE_ACCEPTED = 0x01, // Peer has accepted the invite GROUP_INVITE_CONFIRMATION = 0x02, // Peer has confirmed the accepted invite } Group_Invite_Message_Type; /** Group join rejection types. */ typedef enum Group_Join_Rejected { GJ_GROUP_FULL = 0x00, GJ_INVALID_PASSWORD = 0x01, GJ_INVITE_FAILED = 0x02, GJ_INVALID = 0x03, } Group_Join_Rejected; /** Group broadcast packet types */ typedef enum Group_Broadcast_Type { GM_STATUS = 0x00, // Peer changed their status GM_NICK = 0x01, // Peer changed their nickname GM_PLAIN_MESSAGE = 0x02, // Peer sent a normal message GM_ACTION_MESSAGE = 0x03, // Peer sent an action message GM_PRIVATE_MESSAGE = 0x04, // Peer sent a private message GM_PEER_EXIT = 0x05, // Peer left the group GM_KICK_PEER = 0x06, // Peer was kicked from the group GM_SET_MOD = 0x07, // Peer was promoted to or demoted from Moderator role GM_SET_OBSERVER = 0x08, // Peer was demoted to or promoted from Observer role } Group_Broadcast_Type; /*** * Group packet types. * * For a detailed spec, see docs/DHT_Group_Chats_Packet_Spec.md */ typedef enum Group_Packet_Type { /* lossy packets (ID 0 is reserved) */ GP_PING = 0x01, GP_MESSAGE_ACK = 0x02, GP_INVITE_RESPONSE_REJECT = 0x03, /* lossless packets */ GP_CUSTOM_PRIVATE_PACKET = 0xee, GP_FRAGMENT = 0xef, GP_KEY_ROTATION = 0xf0, GP_TCP_RELAYS = 0xf1, GP_CUSTOM_PACKET = 0xf2, GP_BROADCAST = 0xf3, GP_PEER_INFO_REQUEST = 0xf4, GP_PEER_INFO_RESPONSE = 0xf5, GP_INVITE_REQUEST = 0xf6, GP_INVITE_RESPONSE = 0xf7, GP_SYNC_REQUEST = 0xf8, GP_SYNC_RESPONSE = 0xf9, GP_TOPIC = 0xfa, GP_SHARED_STATE = 0xfb, GP_MOD_LIST = 0xfc, GP_SANCTIONS_LIST = 0xfd, GP_FRIEND_INVITE = 0xfe, GP_HS_RESPONSE_ACK = 0xff, } Group_Packet_Type; /** Lossless message acknowledgement types. */ typedef enum Group_Message_Ack_Type { GR_ACK_RECV = 0x00, // indicates a message has been received GR_ACK_REQ = 0x01, // indicates a message needs to be re-sent } Group_Message_Ack_Type; /** @brief Returns the GC_Connection object associated with `peer_number`. * Returns null if peer_number does not designate a valid peer. */ non_null() GC_Connection *get_gc_connection(const GC_Chat *chat, int peer_number); /** @brief Returns the jenkins hash of a 32 byte public encryption key. */ non_null() uint32_t gc_get_pk_jenkins_hash(const uint8_t *public_key); /** @brief Check if peer with the public encryption key is in peer list. * * Returns the peer number if peer is in the peer list. * Returns -1 if peer is not in the peer list. * * If `confirmed` is true the peer number will only be returned if the peer is confirmed. */ non_null() int get_peer_number_of_enc_pk(const GC_Chat *chat, const uint8_t *public_enc_key, bool confirmed); /** @brief Encrypts `data` of size `length` using the peer's shared key and a new nonce. * * Adds encrypted header consisting of: packet type, message_id (only for lossless packets). * Adds plaintext header consisting of: packet identifier, self public encryption key, nonce. * * Return length of encrypted packet on success. * Return -1 if plaintext length is invalid. * Return -2 if malloc fails. * Return -3 if encryption fails. */ non_null(1, 2, 3, 4, 5) nullable(7) int group_packet_wrap( const Logger *log, const Random *rng, const uint8_t *self_pk, const uint8_t *shared_key, uint8_t *packet, uint16_t packet_size, const uint8_t *data, uint16_t length, uint64_t message_id, uint8_t gp_packet_type, uint8_t net_packet_type); /** @brief Returns the size of a wrapped/encrypted packet with a plain size of `length`. * * `packet_type` should be either NET_PACKET_GC_LOSSY or NET_PACKET_GC_LOSSLESS. */ uint16_t gc_get_wrapped_packet_size(uint16_t length, Net_Packet_Type packet_type); /** @brief Sends a plain message or an action, depending on type. * * `length` must not exceed MAX_GC_MESSAGE_SIZE and must not be equal to zero. * `message_id` should either point to a uint32_t or be NULL. * * Returns 0 on success. * Returns -1 if the message is too long. * Returns -2 if the message pointer is NULL or length is zero. * Returns -3 if the message type is invalid. * Returns -4 if the sender does not have permission to speak. * Returns -5 if the packet fails to send. */ non_null(1, 2, 3, 4) nullable(5) int gc_send_message(const GC_Chat *chat, const uint8_t *message, uint16_t length, uint8_t type, uint32_t *message_id); /** @brief Sends a private message to peer_id. * * `length` must not exceed MAX_GC_MESSAGE_SIZE and must not be equal to zero. * * Returns 0 on success. * Returns -1 if the message is too long. * Returns -2 if the message pointer is NULL or length is zero. * Returns -3 if the peer_id is invalid. * Returns -4 if the message type is invalid. * Returns -5 if the sender has the observer role. * Returns -6 if the packet fails to send. */ non_null() int gc_send_private_message(const GC_Chat *chat, uint32_t peer_id, uint8_t type, const uint8_t *message, uint16_t length); /** @brief Sends a custom packet to the group. If lossless is true, the packet will be lossless. * * `length` must not exceed MAX_GC_MESSAGE_SIZE and must not be equal to zero. * * Returns 0 on success. * Returns -1 if the message is too long. * Returns -2 if the message pointer is NULL or length is zero. * Returns -3 if the sender has the observer role. */ non_null() int gc_send_custom_packet(const GC_Chat *chat, bool lossless, const uint8_t *data, uint16_t length); /** @brief Sends a custom private packet to the peer designated by peer_id. * * `length` must not exceed MAX_GC_MESSAGE_SIZE and must not be equal to zero. * * @retval 0 on success. * @retval -1 if the message is too long. * @retval -2 if the message pointer is NULL or length is zero. * @retval -3 if the supplied peer_id does not designate a valid peer. * @retval -4 if the sender has the observer role. * @retval -5 if the packet fails to send. */ non_null() int gc_send_custom_private_packet(const GC_Chat *chat, bool lossless, uint32_t peer_id, const uint8_t *message, uint16_t length); /** @brief Sets ignore for peer_id. * * Returns 0 on success. * Returns -1 if the peer_id is invalid. * Returns -2 if the caller attempted to ignore himself. */ non_null() int gc_set_ignore(const GC_Chat *chat, uint32_t peer_id, bool ignore); /** @brief Sets the group topic and broadcasts it to the group. * * If `length` is equal to zero the topic will be unset. * * Returns 0 on success. * Returns -1 if the topic is too long (must be `<= MAX_GC_TOPIC_SIZE`). * Returns -2 if the caller does not have the required permissions to set the topic. * Returns -3 if the packet cannot be created or signing fails. * Returns -4 if the packet fails */ non_null(1) nullable(2) int gc_set_topic(GC_Chat *chat, const uint8_t *topic, uint16_t length); /** @brief Copies the group topic to `topic`. If topic is null this function has no effect. * * Call `gc_get_topic_size` to determine the allocation size for the `topic` parameter. * * The data written to `topic` is equal to the data received by the last topic callback. */ non_null(1) nullable(2) void gc_get_topic(const GC_Chat *chat, uint8_t *topic); /** @brief Returns the topic length. * * The return value is equal to the `length` agument received by the last topic callback. */ non_null() uint16_t gc_get_topic_size(const GC_Chat *chat); /** @brief Copies group name to `group_name`. If `group_name` is null this function has no effect. * * Call `gc_get_group_name_size` to determine the allocation size for the `group_name` * parameter. */ non_null() void gc_get_group_name(const GC_Chat *chat, uint8_t *group_name); /** @brief Returns the group name length. */ non_null() uint16_t gc_get_group_name_size(const GC_Chat *chat); /** @brief Copies the group password to password. * * If password is null this function has no effect. * * Call the `gc_get_password_size` function to determine the allocation size for * the `password` buffer. * * The data received is equal to the data received by the last password callback. */ non_null() void gc_get_password(const GC_Chat *chat, uint8_t *password); /** @brief Returns the group password length. */ non_null() uint16_t gc_get_password_size(const GC_Chat *chat); /** @brief Returns the group privacy state. * * The value returned is equal to the data receieved by the last privacy_state callback. */ non_null() Group_Privacy_State gc_get_privacy_state(const GC_Chat *chat); /** @brief Returns the group topic lock state. * * The value returned is equal to the data received by the last last topic_lock callback. */ non_null() Group_Topic_Lock gc_get_topic_lock_state(const GC_Chat *chat); /** @brief Returns the group voice state. * * The value returned is equal to the data received by the last voice_state callback. */ non_null() Group_Voice_State gc_get_voice_state(const GC_Chat *chat); /** @brief Returns the group peer limit. * * The value returned is equal to the data receieved by the last peer_limit callback. */ non_null() uint16_t gc_get_max_peers(const GC_Chat *chat); /** @brief Sets your own nick to `nick`. * * `length` cannot exceed MAX_GC_NICK_SIZE. if `length` is zero or `name` is a * null pointer the function call will fail. * * Returns 0 on success. * Returns -1 if group_number is invalid. * Returns -2 if the length is too long. * Returns -3 if the length is zero or nick is a NULL pointer. * Returns -4 if the packet fails to send. */ non_null() int gc_set_self_nick(const Messenger *m, int group_number, const uint8_t *nick, uint16_t length); /** @brief Copies your own name to `nick`. * * If `nick` is null this function has no effect. */ non_null() void gc_get_self_nick(const GC_Chat *chat, uint8_t *nick); /** @brief Return your own nick length. * * If no nick was set before calling this function it will return 0. */ non_null() uint16_t gc_get_self_nick_size(const GC_Chat *chat); /** @brief Returns your own group role. */ non_null() Group_Role gc_get_self_role(const GC_Chat *chat); /** @brief Return your own status. */ non_null() uint8_t gc_get_self_status(const GC_Chat *chat); /** @brief Returns your own peer id. */ non_null() uint32_t gc_get_self_peer_id(const GC_Chat *chat); /** @brief Copies self public key to `public_key`. * * If `public_key` is null this function has no effect. * * This key is permanently tied to our identity for `chat` until we explicitly * exit the group. This key is the only way for other peers to reliably identify * us across client restarts. */ non_null(1) nullable(2) void gc_get_self_public_key(const GC_Chat *chat, uint8_t *public_key); /** @brief Copies nick designated by `peer_id` to `name`. * * Call `gc_get_peer_nick_size` to determine the allocation size for the `name` parameter. * * The data written to `name` is equal to the data received by the last nick_change callback. * * Returns true on success. * Returns false if peer_id is invalid. */ non_null(1) nullable(3) bool gc_get_peer_nick(const GC_Chat *chat, uint32_t peer_id, uint8_t *name); /** @brief Returns the length of the nick for the peer designated by `peer_id`. * Returns -1 if peer_id is invalid. * * The value returned is equal to the `length` argument received by the last * nick_change callback. */ non_null() int gc_get_peer_nick_size(const GC_Chat *chat, uint32_t peer_id); /** @brief Copies peer_id's public key to `public_key`. * * This key is permanently tied to the peer's identity for `chat` until they explicitly * exit the group. This key is the only way for to reliably identify the given peer * across client restarts. * * `public_key` shold have room for at least ENC_PUBLIC_KEY_SIZE bytes. * * Returns 0 on success. * Returns -1 if peer_id is invalid or doesn't correspond to a valid peer connection. * Returns -2 if `public_key` is null. */ non_null(1) nullable(3) int gc_get_peer_public_key_by_peer_id(const GC_Chat *chat, uint32_t peer_id, uint8_t *public_key); /** @brief Gets the connection status for peer associated with `peer_id`. * * Returns 2 if we have a direct (UDP) connection with a peer. * Returns 1 if we have an indirect (TCP) connection with a peer. * Returns 0 if peer_id is invalid or corresponds to ourselves. * * Note: Return values must correspond to Tox_Connection enum in API. */ non_null() unsigned int gc_get_peer_connection_status(const GC_Chat *chat, uint32_t peer_id); /** @brief Sets the caller's status to `status`. * * Returns 0 on success. * Returns -1 if the group_number is invalid. * Returns -2 if the packet failed to send. */ non_null() int gc_set_self_status(const Messenger *m, int group_number, Group_Peer_Status status); /** @brief Returns the status of peer designated by `peer_id`. * Returns UINT8_MAX on failure. * * The status returned is equal to the last status received through the status_change * callback. */ non_null() uint8_t gc_get_status(const GC_Chat *chat, uint32_t peer_id); /** @brief Returns the group role of peer designated by `peer_id`. * Returns UINT8_MAX on failure. * * The role returned is equal to the last role received through the moderation callback. */ non_null() uint8_t gc_get_role(const GC_Chat *chat, uint32_t peer_id); /** @brief Sets the role of peer_id. role must be one of: GR_MODERATOR, GR_USER, GR_OBSERVER * * Returns 0 on success. * Returns -1 if the group_number is invalid. * Returns -2 if the peer_id is invalid. * Returns -3 if caller does not have sufficient permissions for the action. * Returns -4 if the role assignment is invalid. * Returns -5 if the role failed to be set. * Returns -6 if the caller attempted to kick himself. */ non_null() int gc_set_peer_role(const Messenger *m, int group_number, uint32_t peer_id, Group_Role new_role); /** @brief Sets the group password and distributes the new shared state to the group. * * This function requires that the shared state be re-signed and will only work for the group founder. * * If `password` is null or `password_length` is 0 the password will be unset for the group. * * Returns 0 on success. * Returns -1 if the caller does not have sufficient permissions for the action. * Returns -2 if the password is too long. * Returns -3 if the packet failed to send. * Returns -4 if malloc failed. */ non_null(1) nullable(2) int gc_founder_set_password(GC_Chat *chat, const uint8_t *password, uint16_t password_length); /** @brief Sets the topic lock and distributes the new shared state to the group. * * When the topic lock is enabled, only the group founder and moderators may set the topic. * When disabled, all peers except those with the observer role may set the topic. * * This function requires that the shared state be re-signed and will only work for the group founder. * * Returns 0 on success. * Returns -1 if group_number is invalid. * Returns -2 if `topic_lock` is an invalid type. * Returns -3 if the caller does not have sufficient permissions for this action. * Returns -4 if the group is disconnected. * Returns -5 if the topic lock could not be set. * Returns -6 if the packet failed to send. */ non_null() int gc_founder_set_topic_lock(const Messenger *m, int group_number, Group_Topic_Lock new_lock_state); /** @brief Sets the group privacy state and distributes the new shared state to the group. * * This function requires that the shared state be re-signed and will only work for the group founder. * * If an attempt is made to set the privacy state to the same state that the group is already * in, the function call will be successful and no action will be taken. * * Returns 0 on success. * Returns -1 if group_number is invalid. * Returns -2 if the caller does not have sufficient permissions for this action. * Returns -3 if the group is disconnected. * Returns -4 if the privacy state could not be set. * Returns -5 if the packet failed to send. */ non_null() int gc_founder_set_privacy_state(const Messenger *m, int group_number, Group_Privacy_State new_privacy_state); /** @brief Sets the group voice state and distributes the new shared state to the group. * * This function requires that the shared state be re-signed and will only work for the group founder. * * If an attempt is made to set the voice state to the same state that the group is already * in, the function call will be successful and no action will be taken. * * Returns 0 on success. * Returns -1 if group_number is invalid. * Returns -2 if the caller does not have sufficient permissions for this action. * Returns -3 if the group is disconnected. * Returns -4 if the voice state could not be set. * Returns -5 if the packet failed to send. */ non_null() int gc_founder_set_voice_state(const Messenger *m, int group_number, Group_Voice_State new_voice_state); /** @brief Sets the peer limit to maxpeers and distributes the new shared state to the group. * * This function requires that the shared state be re-signed and will only work for the group founder. * * Returns 0 on success. * Returns -1 if the caller does not have sufficient permissions for this action. * Returns -2 if the peer limit could not be set. * Returns -3 if the packet failed to send. */ non_null() int gc_founder_set_max_peers(GC_Chat *chat, uint16_t max_peers); /** @brief Removes peer designated by `peer_id` from peer list and sends a broadcast instructing * all other peers to remove the peer from their peerlist as well. * * This function will not trigger the peer_exit callback for the caller. * * Returns 0 on success. * Returns -1 if the group_number is invalid. * Returns -2 if the peer_id is invalid. * Returns -3 if the caller does not have sufficient permissions for this action. * Returns -4 if the action failed. * Returns -5 if the packet failed to send. * Returns -6 if the caller attempted to kick himself. */ non_null() int gc_kick_peer(const Messenger *m, int group_number, uint32_t peer_id); /** @brief Copies the chat_id to dest. If dest is null this function has no effect. * * `dest` should have room for at least CHAT_ID_SIZE bytes. */ non_null(1) nullable(2) void gc_get_chat_id(const GC_Chat *chat, uint8_t *dest); /** Group callbacks */ non_null(1) nullable(2) void gc_callback_message(const Messenger *m, gc_message_cb *function); non_null(1) nullable(2) void gc_callback_private_message(const Messenger *m, gc_private_message_cb *function); non_null(1) nullable(2) void gc_callback_custom_packet(const Messenger *m, gc_custom_packet_cb *function); non_null(1) nullable(2) void gc_callback_custom_private_packet(const Messenger *m, gc_custom_private_packet_cb *function); non_null(1) nullable(2) void gc_callback_moderation(const Messenger *m, gc_moderation_cb *function); non_null(1) nullable(2) void gc_callback_nick_change(const Messenger *m, gc_nick_change_cb *function); non_null(1) nullable(2) void gc_callback_status_change(const Messenger *m, gc_status_change_cb *function); non_null(1) nullable(2) void gc_callback_topic_change(const Messenger *m, gc_topic_change_cb *function); non_null(1) nullable(2) void gc_callback_peer_limit(const Messenger *m, gc_peer_limit_cb *function); non_null(1) nullable(2) void gc_callback_privacy_state(const Messenger *m, gc_privacy_state_cb *function); non_null(1) nullable(2) void gc_callback_topic_lock(const Messenger *m, gc_topic_lock_cb *function); non_null(1) nullable(2) void gc_callback_password(const Messenger *m, gc_password_cb *function); non_null(1) nullable(2) void gc_callback_peer_join(const Messenger *m, gc_peer_join_cb *function); non_null(1) nullable(2) void gc_callback_peer_exit(const Messenger *m, gc_peer_exit_cb *function); non_null(1) nullable(2) void gc_callback_self_join(const Messenger *m, gc_self_join_cb *function); non_null(1) nullable(2) void gc_callback_rejected(const Messenger *m, gc_rejected_cb *function); non_null(1) nullable(2) void gc_callback_voice_state(const Messenger *m, gc_voice_state_cb *function); /** @brief The main loop. Should be called with every Messenger iteration. */ non_null(1) nullable(2) void do_gc(GC_Session *c, void *userdata); /** * Make sure that DHT is initialized before calling this. * Returns a NULL pointer on failure. */ nullable(1) GC_Session *new_dht_groupchats(Messenger *m); /** @brief Cleans up groupchat structures and calls `gc_group_exit()` for every group chat */ nullable(1) void kill_dht_groupchats(GC_Session *c); /** @brief Loads a previously saved group and attempts to join it. * * `bu` is the packed group info. * * Returns group_number on success. * Returns -1 on failure. */ non_null() int gc_group_load(GC_Session *c, Bin_Unpack *bu); /** * @brief Saves info from `chat` to `bp` in binary format. */ non_null() void gc_group_save(const GC_Chat *chat, Bin_Pack *bp); /** @brief Creates a new group and adds it to the group sessions group array. * * The caller of this function has founder role privileges. * * The client should initiate its peer list with self info after calling this function, as * the peer_join callback will not be triggered. * * Return -1 if the nick or group name is too long. * Return -2 if the nick or group name is empty. * Return -3 if the the group object fails to initialize. * Return -4 if the group state fails to initialize. * Return -5 if the Messenger friend connection fails to initialize. */ non_null() int gc_group_add(GC_Session *c, Group_Privacy_State privacy_state, const uint8_t *group_name, uint16_t group_name_length, const uint8_t *nick, size_t nick_length); /** @brief Joins a group designated by `chat_id`. * * This function creates a new GC_Chat object, adds it to the chats array, and sends a DHT * announcement to find peers in the group associated with `chat_id`. Once a peer has been * found a join attempt will be initiated. * * If the group is not password protected password should be set to NULL and password_length should be 0. * * Return group_number on success. * Return -1 if the group object fails to initialize. * Return -2 if chat_id is NULL or a group with chat_id already exists in the chats array. * Return -3 if nick is too long. * Return -4 if nick is empty or nick length is zero. * Return -5 if there is an error setting the group password. * Return -6 if the Messenger friend connection fails to initialize. */ non_null(1, 2, 3) nullable(5) int gc_group_join(GC_Session *c, const uint8_t *chat_id, const uint8_t *nick, size_t nick_length, const uint8_t *passwd, uint16_t passwd_len); /** @brief Disconnects from all peers in a group but saves the group state for later use. * * Return true on sucess. * Return false if the group handler object or chat object is null. */ non_null() bool gc_disconnect_from_group(const GC_Session *c, GC_Chat *chat); /** @brief Disconnects from all peers in a group and attempts to reconnect. * * All self state and credentials are retained. * * Returns 0 on success. * Returns -1 if the group handler object or chat object is null. * Returns -2 if the Messenger friend connection fails to initialize. */ non_null() int gc_rejoin_group(GC_Session *c, GC_Chat *chat); /** @brief Joins a group using the invite data received in a friend's group invite. * * The invite is only valid while the inviter is present in the group. * * Return group_number on success. * Return -1 if the invite data is malformed. * Return -2 if the group object fails to initialize. * Return -3 if nick is too long. * Return -4 if nick is empty or nick length is zero. * Return -5 if there is an error setting the password. * Return -6 if friend doesn't exist. * Return -7 if sending packet failed. */ non_null(1, 3, 5) nullable(7) int gc_accept_invite(GC_Session *c, int32_t friend_number, const uint8_t *data, uint16_t length, const uint8_t *nick, size_t nick_length, const uint8_t *passwd, uint16_t passwd_len); typedef bool gc_send_group_invite_packet_cb(const Messenger *m, uint32_t friendnumber, const uint8_t *packet, uint16_t length); /** @brief Invites friend designated by `friendnumber` to chat. * Packet includes: Type, chat_id, TCP node or packed IP_Port. * * Return 0 on success. * Return -1 if friendnumber does not exist. * Return -2 on failure to create the invite data. * Return -3 if the packet fails to send. */ non_null() int gc_invite_friend(const GC_Session *c, GC_Chat *chat, int32_t friend_number, gc_send_group_invite_packet_cb *callback); /** @brief Leaves a group and sends an exit broadcast packet with an optional parting message. * * All group state is permanently lost, including keys and roles. * * Return 0 on success. * Return -1 if the parting message is too long. * Return -2 if the parting message failed to send. */ non_null(1, 2) nullable(3) int gc_group_exit(GC_Session *c, GC_Chat *chat, const uint8_t *message, uint16_t length); /** @brief Returns true if `chat` is a valid group chat. * * A valid group chat constitutes an initialized chat instance with a non-zero shared state version. * The shared state version will be non-zero either if a peer has created the group, or if * they have ever successfully connected to the group. */ non_null() bool gc_group_is_valid(const GC_Chat *chat); /** @brief Returns the number of active groups in `c`. */ non_null() uint32_t gc_count_groups(const GC_Session *c); /** @brief Returns true if peer_number exists */ non_null() bool gc_peer_number_is_valid(const GC_Chat *chat, int peer_number); /** @brief Return group_number's GC_Chat pointer on success * Return NULL on failure */ non_null() GC_Chat *gc_get_group(const GC_Session *c, int group_number); /** @brief Sends a lossy message acknowledgement to peer associated with `gconn`. * * If `type` is GR_ACK_RECV we send a read-receipt for read_id's packet. If `type` is GR_ACK_REQ * we send a request for the respective id's packet. * * Requests are limited to one per second per peer. * * @retval true on success. */ non_null() bool gc_send_message_ack(const GC_Chat *chat, GC_Connection *gconn, uint64_t message_id, Group_Message_Ack_Type type); /** @brief Helper function for `handle_gc_lossless_packet()`. * * Note: This function may modify the peer list and change peer numbers. * * @retval true if packet is successfully handled. */ non_null(1, 2) nullable(4, 7) bool handle_gc_lossless_helper(const GC_Session *c, GC_Chat *chat, uint32_t peer_number, const uint8_t *data, uint16_t length, uint8_t packet_type, void *userdata); /** @brief Handles an invite accept packet. * * @retval true on success. */ non_null() bool handle_gc_invite_accepted_packet(const GC_Session *c, int friend_number, const uint8_t *data, uint16_t length); /** @brief Return true if `chat_id` is not present in our group sessions array. * * `length` must be at least CHAT_ID_SIZE bytes in length. */ non_null() bool group_not_added(const GC_Session *c, const uint8_t *chat_id, uint32_t length); /** @brief Handles an invite confirmed packet. * * Return 0 on success. * Return -1 if length is invalid. * Return -2 if data contains invalid chat_id. * Return -3 if data contains invalid peer info. * Return -4 if `friend_number` does not designate a valid friend. * Return -5 if data contains invalid connection info. */ non_null() int handle_gc_invite_confirmed_packet(const GC_Session *c, int friend_number, const uint8_t *data, uint16_t length); /** @brief Returns the group designated by `public_key`. * Returns null if group does not exist. */ non_null() GC_Chat *gc_get_group_by_public_key(const GC_Session *c, const uint8_t *public_key); /** @brief Attempts to add peers from `announces` to our peer list and initiate an invite request. * * Returns the number of peers added on success. * Returns -1 on failure. */ non_null() int gc_add_peers_from_announces(GC_Chat *chat, const GC_Announce *announces, uint8_t gc_announces_count); #endif // GROUP_CHATS_H