ft_irc

Internet Relay Chat

Summary: This project is about creating your own IRC server. You will use an actual IRC client to connect to your server and test it. Internet is ruled by solid standards protocols that allow connected computers to interact with each other. It’s always a good thing to know.

Version: 8

Contents

• I Introduction
• II General rules
• III Mandatory Part
  • III.1 Requirements
  • III.2 For MacOS only
  • III.3 Test example
• IV Bonus part
• V Submission and peer-evaluation

Chapter I

Introduction

Internet Relay Chat or IRC is a text-based communication protocol on the Internet. It offers real-time messaging that can be either public or private. Users can exchange direct messages and join group channels.

IRC clients connect to IRC servers in order to join channels. IRC servers are connected together to form a network.

Chapter II

General rules

• Your program should not crash in any circumstances (even when it runs out of memory), and should not quit unexpectedly. If it happens, your project will be considered non-functional and your grade will be 0.
• You have to turn in aMakefilewhich will compile your source files. It must not relink.
• YourMakefilemust at least contain the rules: $(NAME),all,clean,fcleanandre.
• Compile your code withc++and the flags-Wall -Wextra -Werror
• Your code must comply with the C++ 98 standard. Then, it should still compile if you add the flag-std=c++98.
• Try to always develop using the mostC++features you can (for example, choose over<string.h>). You are allowed to useCfunctions, but always prefer theirC++versions if possible.
• Any external library andBoostlibraries are forbidden.

Chapter III

Mandatory Part

Program name ircserv
Turn in files Makefile, *.{h, hpp}, *.cpp, *.tpp, *.ipp,
an optional configuration file
Makefile NAME, all, clean, fclean, re
Arguments port: The listening port
password: The connection password
External functs. Everything in C++ 98.
socket, close, setsockopt, getsockname,
getprotobyname, gethostbyname, getaddrinfo,
freeaddrinfo, bind, connect, listen, accept, htons,
htonl, ntohs, ntohl, inet_addr, inet_ntoa, send,
recv, signal, sigaction, lseek, fstat, fcntl, poll
(or equivalent)
Libft authorized n/a
Description An IRC server in C++ 98

You have to develop an IRC server in C++ 98.

You mustn’t develop a client.
You mustn’t handle server-to-server communication.

Your executable will be run as follows:
./ircserv <port> <password>

• port: The port number on which your IRC server will be listening to for incoming IRC connections.
• password: The connection password. It will be needed by any IRC client that tries to connect to your server.

Even if poll() is mentionned in the subject and the evaluation scale,
you can use any equivalent such as select(), kqueue(), or epoll().

ft_irc Internet Relay Chat

III.1 Requirements

• The server must be capable of handling multiple clients at the same time and never hang.
• Forking is not allowed. All I/O operations must be non-blocking.
• Only 1 poll()(or equivalent) can be used for handling all these operations (read, write, but also listen, and so forth).

Because you have to use non-blocking file descriptors, it is
possible to use read/recv or write/send functions with no poll()
(or equivalent), and your server wouldn’t be blocking.
But it would consume more system resources.
Thus, if you try to read/recv or write/send in any file descriptor
without using poll() (or equivalent), your grade will be 0.

• Several IRC clients exist. You have to choose one of them as a reference. Your reference client will be used during the evaluation process.
• Your reference client must be able to connect to your server without encountering any error.
• Communication between client and server has to be done viaTCP/IP(v4 or v6).
• Using your reference client with your server must be similar to using it with any official IRC server. However, you only have to implement the following features:

◦ You must be able to authenticate, set a nickname, a username, join a channel,
send and receive private messages using your reference client.

◦ All the messages sent from one client to a channel have to be forwarded to
every other client that joined the channel.

◦ You must haveoperatorsand regular users.
◦ Then, you have to implement the commands that are specific to channel
operators:
∗ KICK - Eject a client from the channel
∗ INVITE - Invite a client to a channel
∗ TOPIC - Change or view the channel topic
∗ MODE - Change the channel’s mode:
· i: Set/remove Invite-only channel
· t: Set/remove the restrictions of the TOPIC command to channel
operators
· k: Set/remove the channel key (password)
· o: Give/take channel operator privilege

ft_irc Internet Relay Chat

· l: Set/remove the user limit to channel

• Of course, you are expected to write a clean code.

III.2 For MacOS only

Since MacOS doesn’t implement write() the same way as other Unix
OSes, you are allowed to use fcntl().
You must use file descriptors in non-blocking mode in order to get a
behavior similar to the one of other Unix OSes.

However, you are allowed to use fcntl() only as follows:
fcntl(fd, F_SETFL, O_NONBLOCK);
Any other flag is forbidden.

III.3 Test example

Verify absolutely every possible error and issue (receiving partial data, low bandwidth, and so forth).

To ensure that your server correctly processes everything that you send to it, the following simple test usingnccan be done:

\$> nc 127.0.0.1 6667
com^Dman^Dd
\$>

Usectrl+Dto send the command in several parts: ’com’, then ’man’, then ’d\n’.

In order to process a command, you have to first aggregate the received packets in order to rebuild it.

Chapter IV

Bonus part

Here are the extra features you can add to your IRC server so it looks even more like and actual IRC server:

• Handle file transfer.
• A bot.

The bonus part will only be assessed if the mandatory part is
PERFECT. Perfect means the mandatory part has been integrally done
and works without malfunctioning. If you have not passed ALL the
mandatory requirements, your bonus part will not be evaluated at all.

Chapter V

Submission and peer-evaluation

Turn in your assignment in yourGitrepository as usual. Only the work inside your repos- itory will be evaluated during the defense. Don’t hesitate to double check the names of your files to ensure they are correct.

You are encouraged to create test programs for your project even though they won’t be submitted and won’t be graded. Those tests could be especially useful to test your server during defense, but also your peer’s if you have to evaluate anotherft_irc one day. Indeed, you are free to use whatever tests you need during the evaluation process.

Your reference client will be used during the evaluation process.

16D85ACC441674FBA2DF65190663F432222F81AA0248081A7C1C1823F7A96F0B
15056E97427E5B22F07132659EC8D88B574BD62C94BB654D5835AAD889B014E
709F6E