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/* Messenger.h
*
* An implementation of a simple text chat only messenger on the tox network core.
*
* NOTE: All the text in the messages must be encoded using UTF-8
*
* 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 <http://www.gnu.org/licenses/>.
*
*/
#ifndef MESSENGER_H
#define MESSENGER_H
#include "net_crypto.h"
#include "DHT.h"
#include "friend_requests.h"
#include "LAN_discovery.h"
#include "group_chats.h"
#define MAX_NAME_LENGTH 128
#define MAX_STATUSMESSAGE_LENGTH 1007
#define FRIEND_ADDRESS_SIZE (crypto_box_PUBLICKEYBYTES + sizeof(uint32_t) + sizeof(uint16_t))
#define PACKET_ID_PING 0
#define PACKET_ID_NICKNAME 48
#define PACKET_ID_STATUSMESSAGE 49
#define PACKET_ID_USERSTATUS 50
#define PACKET_ID_RECEIPT 65
#define PACKET_ID_MESSAGE 64
#define PACKET_ID_ACTION 63
#define PACKET_ID_MSI 69
#define PACKET_ID_FILE_SENDREQUEST 80
#define PACKET_ID_FILE_CONTROL 81
#define PACKET_ID_FILE_DATA 82
#define PACKET_ID_INVITE_GROUPCHAT 144
#define PACKET_ID_JOIN_GROUPCHAT 145
#define PACKET_ID_ACCEPT_GROUPCHAT 146
/* Status definitions. */
enum {
NOFRIEND,
FRIEND_ADDED,
FRIEND_REQUESTED,
FRIEND_CONFIRMED,
FRIEND_ONLINE,
};
/* Errors for m_addfriend
* FAERR - Friend Add Error
*/
enum {
FAERR_TOOLONG = -1,
FAERR_NOMESSAGE = -2,
FAERR_OWNKEY = -3,
FAERR_ALREADYSENT = -4,
FAERR_UNKNOWN = -5,
FAERR_BADCHECKSUM = -6,
FAERR_SETNEWNOSPAM = -7,
FAERR_NOMEM = -8
};
/* Don't assume MAX_STATUSMESSAGE_LENGTH will stay at 128, it may be increased
* to an absurdly large number later.
*/
/* Default start timeout in seconds between friend requests. */
#define FRIENDREQUEST_TIMEOUT 5;
/* Interval between the sending of ping packets. */
#define FRIEND_PING_INTERVAL 5
/* If no packets are recieved from friend in this time interval, kill the connection. */
#define FRIEND_CONNECTION_TIMEOUT (FRIEND_PING_INTERVAL * 2)
/* USERSTATUS -
* Represents userstatuses someone can have.
*/
typedef enum {
USERSTATUS_NONE,
USERSTATUS_AWAY,
USERSTATUS_BUSY,
USERSTATUS_INVALID
}
USERSTATUS;
struct File_Transfers {
uint64_t size;
uint64_t transferred;
uint8_t status; /* 0 == no transfer, 1 = not accepted, 2 = paused by the other, 3 = transferring, 4 = broken, 5 = paused by us */
};
enum {
FILESTATUS_NONE,
FILESTATUS_NOT_ACCEPTED,
FILESTATUS_PAUSED_BY_OTHER,
FILESTATUS_TRANSFERRING,
FILESTATUS_BROKEN,
FILESTATUS_PAUSED_BY_US,
FILESTATUS_TEMPORARY
};
/* This cannot be bigger than 256 */
#define MAX_CONCURRENT_FILE_PIPES 256
enum {
FILECONTROL_ACCEPT,
FILECONTROL_PAUSE,
FILECONTROL_KILL,
FILECONTROL_FINISHED,
FILECONTROL_RESUME_BROKEN
};
typedef struct {
uint8_t client_id[CLIENT_ID_SIZE];
int crypt_connection_id;
uint64_t friendrequest_lastsent; // Time at which the last friend request was sent.
uint32_t friendrequest_timeout; // The timeout between successful friendrequest sending attempts.
uint8_t status; // 0 if no friend, 1 if added, 2 if friend request sent, 3 if confirmed friend, 4 if online.
uint8_t info[MAX_DATA_SIZE]; // the data that is sent during the friend requests we do.
uint8_t name[MAX_NAME_LENGTH];
uint16_t name_length;
uint8_t name_sent; // 0 if we didn't send our name to this friend 1 if we have.
uint8_t *statusmessage;
uint16_t statusmessage_length;
uint8_t statusmessage_sent;
USERSTATUS userstatus;
uint8_t userstatus_sent;
uint16_t info_size; // Length of the info.
uint32_t message_id; // a semi-unique id used in read receipts.
uint8_t receives_read_receipts; // shall we send read receipts to this person?
uint32_t friendrequest_nospam; // The nospam number used in the friend request.
uint64_t ping_lastrecv;
uint64_t ping_lastsent;
struct File_Transfers file_sending[MAX_CONCURRENT_FILE_PIPES];
struct File_Transfers file_receiving[MAX_CONCURRENT_FILE_PIPES];
} Friend;
typedef struct Messenger {
Networking_Core *net;
Net_Crypto *net_crypto;
DHT *dht;
Friend_Requests fr;
uint8_t name[MAX_NAME_LENGTH];
uint16_t name_length;
uint8_t statusmessage[MAX_STATUSMESSAGE_LENGTH];
uint16_t statusmessage_length;
USERSTATUS userstatus;
Friend *friendlist;
uint32_t numfriends;
Group_Chat **chats;
uint32_t numchats;
uint64_t last_LANdiscovery;
void (*friend_message)(struct Messenger *m, int, uint8_t *, uint16_t, void *);
void *friend_message_userdata;
void (*friend_action)(struct Messenger *m, int, uint8_t *, uint16_t, void *);
void *friend_action_userdata;
void (*friend_namechange)(struct Messenger *m, int, uint8_t *, uint16_t, void *);
void *friend_namechange_userdata;
void (*friend_statusmessagechange)(struct Messenger *m, int, uint8_t *, uint16_t, void *);
void *friend_statusmessagechange_userdata;
void (*friend_userstatuschange)(struct Messenger *m, int, USERSTATUS, void *);
void *friend_userstatuschange_userdata;
void (*read_receipt)(struct Messenger *m, int, uint32_t, void *);
void *read_receipt_userdata;
void (*friend_statuschange)(struct Messenger *m, int, uint8_t, void *);
void *friend_statuschange_userdata;
void (*friend_connectionstatuschange)(struct Messenger *m, int, uint8_t, void *);
void *friend_connectionstatuschange_userdata;
void (*group_invite)(struct Messenger *m, int, uint8_t *, void *);
void *group_invite_userdata;
void (*group_message)(struct Messenger *m, int, int, uint8_t *, uint16_t, void *);
void *group_message_userdata;
void (*file_sendrequest)(struct Messenger *m, int, uint8_t, uint64_t, uint8_t *, uint16_t, void *);
void *file_sendrequest_userdata;
void (*file_filecontrol)(struct Messenger *m, int, uint8_t, uint8_t, uint8_t, uint8_t *, uint16_t, void *);
void *file_filecontrol_userdata;
void (*file_filedata)(struct Messenger *m, int, uint8_t, uint8_t *, uint16_t length, void *);
void *file_filedata_userdata;
void (*msi_packet)(struct Messenger *m, int, uint8_t *, uint16_t, void *);
void *msi_packet_userdata;
} Messenger;
/* Format: [client_id (32 bytes)][nospam number (4 bytes)][checksum (2 bytes)]
*
* return FRIEND_ADDRESS_SIZE byte address to give to others.
*/
void getaddress(Messenger *m, uint8_t *address);
/* Add a friend.
* Set the data that will be sent along with friend request.
* address is the address of the friend (returned by getaddress of the friend you wish to add) it must be FRIEND_ADDRESS_SIZE bytes. TODO: add checksum.
* data is the data and length is the length.
*
* return the friend number if success.
* return -1 if message length is too long.
* return -2 if no message (message length must be >= 1 byte).
* return -3 if user's own key.
* return -4 if friend request already sent or already a friend.
* return -5 for unknown error.
* return -6 if bad checksum in address.
* return -7 if the friend was already there but the nospam was different.
* (the nospam for that friend was set to the new one).
* return -8 if increasing the friend list size fails.
*/
int m_addfriend(Messenger *m, uint8_t *address, uint8_t *data, uint16_t length);
/* Add a friend without sending a friendrequest.
* return the friend number if success.
* return -1 if failure.
*/
int m_addfriend_norequest(Messenger *m, uint8_t *client_id);
/* return the friend id associated to that client id.
* return -1 if no such friend.
*/
int getfriend_id(Messenger *m, uint8_t *client_id);
/* Copies the public key associated to that friend id into client_id buffer.
* Make sure that client_id is of size CLIENT_ID_SIZE.
*
* return 0 if success
* return -1 if failure
*/
int getclient_id(Messenger *m, int friend_id, uint8_t *client_id);
/* Remove a friend. */
int m_delfriend(Messenger *m, int friendnumber);
/* Checks friend's connecting status.
*
* return 1 if friend is connected to us (Online).
* return 0 if friend is not connected to us (Offline).
* return -1 on failure.
*/
int m_get_friend_connectionstatus(Messenger *m, int friendnumber);
/* Checks if there exists a friend with given friendnumber.
*
* return 1 if friend exists.
* return 0 if friend doesn't exist.
*/
int m_friend_exists(Messenger *m, int friendnumber);
/* Send a text chat message to an online friend.
*
* return the message id if packet was successfully put into the send queue.
* return 0 if it was not.
*
* You will want to retain the return value, it will be passed to your read_receipt callback
* if one is received.
* m_sendmessage_withid will send a message with the id of your choosing,
* however we can generate an id for you by calling plain m_sendmessage.
*/
uint32_t m_sendmessage(Messenger *m, int friendnumber, uint8_t *message, uint32_t length);
uint32_t m_sendmessage_withid(Messenger *m, int friendnumber, uint32_t theid, uint8_t *message, uint32_t length);
/* Send an action to an online friend.
*
* return the message id if packet was successfully put into the send queue.
* return 0 if it was not.
*
* You will want to retain the return value, it will be passed to your read_receipt callback
* if one is received.
* m_sendaction_withid will send an action message with the id of your choosing,
* however we can generate an id for you by calling plain m_sendaction.
*/
uint32_t m_sendaction(Messenger *m, int friendnumber, uint8_t *action, uint32_t length);
uint32_t m_sendaction_withid(Messenger *m, int friendnumber, uint32_t theid, uint8_t *action, uint32_t length);
/* Set the name and name_length of a friend.
* name must be a string of maximum MAX_NAME_LENGTH length.
* length must be at least 1 byte.
* length is the length of name with the NULL terminator.
*
* return 0 if success.
* return -1 if failure.
*/
int setfriendname(Messenger *m, int friendnumber, uint8_t *name, uint16_t length);
/* Set our nickname.
* name must be a string of maximum MAX_NAME_LENGTH length.
* length must be at least 1 byte.
* length is the length of name with the NULL terminator.
*
* return 0 if success.
* return -1 if failure.
*/
int setname(Messenger *m, uint8_t *name, uint16_t length);
/*
* Get your nickname.
* m - The messanger context to use.
* name - Pointer to a string for the name.
* nlen - The length of the string buffer.
*
* return length of the name.
* return 0 on error.
*/
uint16_t getself_name(Messenger *m, uint8_t *name, uint16_t nlen);
/* Get name of friendnumber and put it in name.
* name needs to be a valid memory location with a size of at least MAX_NAME_LENGTH (128) bytes.
*
* return length of name if success.
* return -1 if failure.
*/
int getname(Messenger *m, int friendnumber, uint8_t *name);
/* returns valid ip port of connected friend on success
* returns zeroed out IP_Port on failure
*/
IP_Port get_friend_ipport(Messenger *m, int friendnumber);
/* Set our user status.
* You are responsible for freeing status after.
*
* returns 0 on success.
* returns -1 on failure.
*/
int m_set_statusmessage(Messenger *m, uint8_t *status, uint16_t length);
int m_set_userstatus(Messenger *m, USERSTATUS status);
/* return the length of friendnumber's status message, including null.
* Pass it into malloc.
*/
int m_get_statusmessage_size(Messenger *m, int friendnumber);
/* Copy friendnumber's status message into buf, truncating if size is over maxlen.
* Get the size you need to allocate from m_get_statusmessage_size.
* The self variant will copy our own status message.
*
* returns the length of the copied data on success
* retruns -1 on failure.
*/
int m_copy_statusmessage(Messenger *m, int friendnumber, uint8_t *buf, uint32_t maxlen);
int m_copy_self_statusmessage(Messenger *m, uint8_t *buf, uint32_t maxlen);
/* return one of USERSTATUS values.
* Values unknown to your application should be represented as USERSTATUS_NONE.
* As above, the self variant will return our own USERSTATUS.
* If friendnumber is invalid, this shall return USERSTATUS_INVALID.
*/
USERSTATUS m_get_userstatus(Messenger *m, int friendnumber);
USERSTATUS m_get_self_userstatus(Messenger *m);
/* Sets whether we send read receipts for friendnumber.
* This function is not lazy, and it will fail if yesno is not (0 or 1).
*/
void m_set_sends_receipts(Messenger *m, int friendnumber, int yesno);
/* Set the function that will be executed when a friend request is received.
* Function format is function(uint8_t * public_key, uint8_t * data, uint16_t length)
*/
void m_callback_friendrequest(Messenger *m, void (*function)(uint8_t *, uint8_t *, uint16_t, void *), void *userdata);
/* Set the function that will be executed when a message from a friend is received.
* Function format is: function(int friendnumber, uint8_t * message, uint32_t length)
*/
void m_callback_friendmessage(Messenger *m, void (*function)(Messenger *m, int, uint8_t *, uint16_t, void *),
void *userdata);
/* Set the function that will be executed when an action from a friend is received.
* Function format is: function(int friendnumber, uint8_t * action, uint32_t length)
*/
void m_callback_action(Messenger *m, void (*function)(Messenger *m, int, uint8_t *, uint16_t, void *), void *userdata);
/* Set the callback for name changes.
* Function(int friendnumber, uint8_t *newname, uint16_t length)
* You are not responsible for freeing newname.
*/
void m_callback_namechange(Messenger *m, void (*function)(Messenger *m, int, uint8_t *, uint16_t, void *),
void *userdata);
/* Set the callback for status message changes.
* Function(int friendnumber, uint8_t *newstatus, uint16_t length)
*
* You are not responsible for freeing newstatus
*/
void m_callback_statusmessage(Messenger *m, void (*function)(Messenger *m, int, uint8_t *, uint16_t, void *),
void *userdata);
/* Set the callback for status type changes.
* Function(int friendnumber, USERSTATUS kind)
*/
void m_callback_userstatus(Messenger *m, void (*function)(Messenger *m, int, USERSTATUS, void *), void *userdata);
/* Set the callback for read receipts.
* Function(int friendnumber, uint32_t receipt)
*
* If you are keeping a record of returns from m_sendmessage,
* receipt might be one of those values, meaning the message
* has been received on the other side.
* Since core doesn't track ids for you, receipt may not correspond to any message.
* In that case, you should discard it.
*/
void m_callback_read_receipt(Messenger *m, void (*function)(Messenger *m, int, uint32_t, void *), void *userdata);
/* Set the callback for connection status changes.
* function(int friendnumber, uint8_t status)
*
* Status:
* 0 -- friend went offline after being previously online.
* 1 -- friend went online.
*
* Note that this callback is not called when adding friends, thus the "after
* being previously online" part.
* It's assumed that when adding friends, their connection status is offline.
*/
void m_callback_connectionstatus(Messenger *m, void (*function)(Messenger *m, int, uint8_t, void *), void *userdata);
/**********GROUP CHATS************/
/* Set the callback for group invites.
*
* Function(Messenger *m, int friendnumber, uint8_t *group_public_key, void *userdata)
*/
void m_callback_group_invite(Messenger *m, void (*function)(Messenger *m, int, uint8_t *, void *), void *userdata);
/* Set the callback for group messages.
*
* Function(Tox *tox, int groupnumber, int friendgroupnumber, uint8_t * message, uint16_t length, void *userdata)
*/
void m_callback_group_message(Messenger *m, void (*function)(Messenger *m, int, int, uint8_t *, uint16_t, void *),
void *userdata);
/* Creates a new groupchat and puts it in the chats array.
*
* return group number on success.
* return -1 on failure.
*/
int add_groupchat(Messenger *m);
/* Delete a groupchat from the chats array.
*
* return 0 on success.
* return -1 if failure.
*/
int del_groupchat(Messenger *m, int groupnumber);
/* Copy the name of peernumber who is in groupnumber to name.
* name must be at least MAX_NICK_BYTES long.
*
* return length of name if success
* return -1 if failure
*/
int m_group_peername(Messenger *m, int groupnumber, int peernumber, uint8_t *name);
/* invite friendnumber to groupnumber
* return 0 on success
* return -1 on failure
*/
int invite_friend(Messenger *m, int friendnumber, int groupnumber);
/* Join a group (you need to have been invited first.)
*
* returns group number on success
* returns -1 on failure.
*/
int join_groupchat(Messenger *m, int friendnumber, uint8_t *friend_group_public_key);
/* send a group message
* return 0 on success
* return -1 on failure
*/
int group_message_send(Messenger *m, int groupnumber, uint8_t *message, uint32_t length);
/****************FILE SENDING*****************/
/* Set the callback for file send requests.
*
* Function(Tox *tox, int friendnumber, uint8_t filenumber, uint64_t filesize, uint8_t *filename, uint16_t filename_length, void *userdata)
*/
void callback_file_sendrequest(Messenger *m, void (*function)(Messenger *m, int, uint8_t, uint64_t, uint8_t *, uint16_t,
void *), void *userdata);
/* Set the callback for file control requests.
*
* Function(Tox *tox, int friendnumber, uint8_t send_receive, uint8_t filenumber, uint8_t control_type, uint8_t *data, uint16_t length, void *userdata)
*
*/
void callback_file_control(Messenger *m, void (*function)(Messenger *m, int, uint8_t, uint8_t, uint8_t, uint8_t *,
uint16_t, void *), void *userdata);
/* Set the callback for file data.
*
* Function(Tox *tox, int friendnumber, uint8_t filenumber, uint8_t *data, uint16_t length, void *userdata)
*
*/
void callback_file_data(Messenger *m, void (*function)(Messenger *m, int, uint8_t, uint8_t *, uint16_t length, void *),
void *userdata);
/* Send a file send request.
* Maximum filename length is 255 bytes.
* return 1 on success
* return 0 on failure
*/
int file_sendrequest(Messenger *m, int friendnumber, uint8_t filenumber, uint64_t filesize, uint8_t *filename,
uint16_t filename_length);
/* Send a file send request.
* Maximum filename length is 255 bytes.
* return file number on success
* return -1 on failure
*/
int new_filesender(Messenger *m, int friendnumber, uint64_t filesize, uint8_t *filename, uint16_t filename_length);
/* Send a file control request.
* send_receive is 0 if we want the control packet to target a sending file, 1 if it targets a receiving file.
*
* return 1 on success
* return 0 on failure
*/
int file_control(Messenger *m, int friendnumber, uint8_t send_receive, uint8_t filenumber, uint8_t message_id,
uint8_t *data, uint16_t length);
/* Send file data.
*
* return 1 on success
* return 0 on failure
*/
int file_data(Messenger *m, int friendnumber, uint8_t filenumber, uint8_t *data, uint16_t length);
/* Give the number of bytes left to be sent/received.
*
* send_receive is 0 if we want the sending files, 1 if we want the receiving.
*
* return number of bytes remaining to be sent/received on success
* return 0 on failure
*/
uint64_t file_dataremaining(Messenger *m, int friendnumber, uint8_t filenumber, uint8_t send_receive);
/*************** A/V related ******************/
/* Set the callback for msi packets.
*
* Function(Messenger *m, int friendnumber, uint8_t *data, uint16_t length, void *userdata)
*/
void m_callback_msi_packet(Messenger *m, void (*function)(Messenger *m, int, uint8_t *, uint16_t, void *),
void *userdata);
/* Send an msi packet.
*
* return 1 on success
* return 0 on failure
*/
int m_msi_packet(Messenger *m, int friendnumber, uint8_t *data, uint16_t length);
/**********************************************/
/* Run this at startup.
* return allocated instance of Messenger on success.
* return 0 if there are problems.
*/
Messenger *new_messenger(uint8_t ipv6enabled);
/* Run this before closing shop
* Free all datastructures.
*/
void kill_messenger(Messenger *M);
/* The main loop that needs to be run at least 20 times per second. */
void do_messenger(Messenger *m);
/*
* functions to avoid excessive polling
*/
int wait_prepare_messenger(Messenger *m, uint8_t *data, uint16_t *lenptr);
int wait_execute_messenger(Messenger *m, uint8_t *data, uint16_t len, uint16_t milliseconds);
void wait_cleanup_messenger(Messenger *m, uint8_t *data, uint16_t len);
/* SAVING AND LOADING FUNCTIONS: */
/* return size of the messenger data (for saving). */
uint32_t messenger_size(Messenger *m);
/* Save the messenger in data (must be allocated memory of size Messenger_size()) */
void messenger_save(Messenger *m, uint8_t *data);
/* Load the messenger from data of size length. */
int messenger_load(Messenger *m, uint8_t *data, uint32_t length);
/* Return the number of friends in the instance m.
* You should use this to determine how much memory to allocate
* for copy_friendlist. */
uint32_t count_friendlist(Messenger *m);
/* Copy a list of valid friend IDs into the array out_list.
* If out_list is NULL, returns 0.
* Otherwise, returns the number of elements copied.
* If the array was too small, the contents
* of out_list will be truncated to list_size. */
uint32_t copy_friendlist(Messenger *m, int *out_list, uint32_t list_size);
/* Allocate and return a list of valid friend id's. List must be freed by the
* caller.
*
* retun 0 if success.
* return -1 if failure.
*/
int get_friendlist(Messenger *m, int **out_list, uint32_t *out_list_length);
#endif
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