IRC SERVER
The goal of this project is to make you write your own IRC server.
IRC SERVER Documentation
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OUR OWN IRC SERVER

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USAGE

SERVER

Version used RFC 1459 https://datatracker.ietf.org/doc/html/rfc1459

make

./ircserv <port> <password>

CLIENT

telnet <serverip> <port> o nc <serverip> <port>

  • The ircserver must be tested with Graphical Official Irc clients as limechat, weechat, textualchat

COMMANDS DOCS

https://en.wikipedia.org/wiki/List_of_Internet_Relay_Chat_commands

  • pass -> Sets a connection password.This command must be sent before the NICK/USER registration combination 
    ex "pass <password>"
  • nick -> Allows a client to change their IRC nickname 
    ex "/nick <nickname>"
  • privmsg -> Sends message to msgtarget, which is usually a user or channel. 
    ex: "/privmsg msgtarget :message"
  • ping -> Lets you determine the network distance between your computer and other users 
    ex: "/ping <nickname>"
  • names -> Returns a list of who is on the comma-separated list of <channels>, by channel name. 
    ex: "/names <channel>"
  • join -> Makes the client join the channels in the comma-separated list, specifying the passwords, if needed 
    ex: "/join <channels> <keys>"
  • part -> Causes a user to leave the channels in the comma-separated list . 
    ex: "/part <channel>"
  • topic -> Allows the client to query or set the channel topic on channel 
    ex: "/topic <channel>"
  • list -> Lists all channels on the server 
    ex: "/list"
  • invites -> Invites nickname to the channel channel 
    ex: "/invites <nickname> <channel>"
  • kick -> Forcibly removes client from channel 
    ex: "/kick <client> <channel>"

[](#message-format)Message Format

An IRC message is a single line, delimited by a pair of CR ‘(’\r', 0x0D)andLF('
', 0x0A)` characters.

  • When reading messages from a stream, read the incoming data into a buffer. Only parse and process a message once you encounter the \r\n at the end of it. If you encounter an empty message, silently ignore it.
  • When sending messages, ensure that a pair of \r\n characters follows every single message your software sends out.

Messages have this format, as rough ABNF: 

  message         ::= ['@' <tags> SPACE] [':' <source> SPACE] <command> <parameters> <crlf>
  SPACE           ::=  %x20 *( %x20 )   ; space character(s)
  crlf            ::=  %x0D %x0A        ; "carriage return" "linefeed"

The specific parts of an IRC message are:

  • tags: Optional metadata on a message, starting with ‘(’@', 0x40).
  • **source**: Optional note of where the message came from, starting with(':', 0x3A)`.
  • command: The specific command this message represents.
  • parameters: If it exists, data relevant to this specific command.

These message parts, and parameters themselves, are separated by one or more ASCII SPACE characters ‘(’ ', 0x20)`.

Most IRC servers limit messages to 512 bytes in length, including the trailing CR-LF characters. Implementations which include message tags need to allow additional bytes for the tags section of a message; clients must allow 8191 additional bytes and servers must allow 4096 additional bytes.

NUMERIC REPLIES

https://modern.ircdocs.horse/#numerics

RPL_WELCOME (001)

  • Message: "-client- :Welcome to the -networkname- Network, -nick-[!<user>@<host>]"
  • Usecase: After client registration

RPL_YOURHOST (002)

  • Message: "-client- :Your host is -servername-, running version -version-"
  • Usecase: Part of the post-registration greeting

RPL_CREATED (003)

  • Message: "-client- :This server was created -datetime-"
  • Usecase: Part of the post-registration greeting,

RPL_MYINFO (004)

RPL_ISUPPORT (005)

RPL_BOUNCE (010)

RPL_UMODEIS (221)

  • Message:

  • Usecase:

    RPL_LUSERCLIENT (251)

  • Message:

  • Usecase:

    RPL_LUSEROP (252)

  • Message:

  • Usecase:

    RPL_LUSERUNKNOWN (253)

  • Message:

  • Usecase:

    RPL_LUSERCHANNELS (254)

  • Message:

  • Usecase:

    RPL_LUSERME (255)

  • Message:
  • Usecase:

ADMIN

RPL_ADMINME (256)

#

RPL_TRYAGAIN (263)

  • Message: "-client- -command- :Please wait a while and try again."
  • Usecase: When a server drops a command without processing it, this numeric MUST be sent to inform the client.

LUSERS

RPL_LOCALUSERS (265)

#

RPL_WHOISCERTFP (276)

AWAY

RPL_AWAY (301)

WHO

RPL_NOWAWAY (306)

  • Message:

  • Usecase:

    RPL_WHOREPLY (352)

  • Message:

  • Usecase:

    RPL_ENDOFWHO (315)

  • Message:

  • Usecase:

    RPL_WHOISREGNICK (307)

  • Message:

  • Usecase:

    RPL_WHOISUSER (311)

  • Message:

  • Usecase:

    RPL_WHOISSERVER (312)

  • Message:

  • Usecase:

    RPL_WHOISOPERATOR (313)

  • Message:

  • Usecase:

    RPL_WHOWASUSER (314)

  • Message:

  • Usecase:

    RPL_WHOISIDLE (317)

  • Message:
  • Usecase:

RPL_ENDOFWHOIS (318)

RPL_WHOISCHANNELS (319)

RPL_WHOISSPECIAL (320)

LIST

RPL_LISTSTART (321)

  • Message: "-client- Channel :Users Name"
  • Usecase: this numeric marks the start of a channel list

RPL_LIST (322)

  • Message: "-client- -channel- -client count- :-topic-"
  • Usecase: Sent as a reply to the LIST command,information about a channel to the client. -channel- is the name of the channel. -client count- is an integer indicating how many clients are joined to that channel. -topic- is the channel’s topic

RPL_LISTEND (323)

  • Message: "-client- :End of /LIST"
  • Usecase: Sent as a reply to the LIST command, this numeric indicates the end of a LIST response.

#

RPL_CHANNELMODEIS (324)

RPL_WHOISACCOUNT (330)

RPL_NOTOPIC (331)

RPL_TOPIC (332)

RPL_TOPICWHOTIME (333)

RPL_WHOISACTUALLY (338)

RPL_INVITING (341)

RPL_EXCEPTLIST (348)

RPL_VERSION (351)

RPL_NAMREPLY (353)

NAMES

RPL_ENDOFNAMES (366)

  • Message: "-client- -channel- :End of /NAMES list"
  • Usecase: Sent as a reply to the NAMES command, this numeric specifies the end of a list of channel member names.

RPL_BANLIST (367)

RPL_ENDOFBANLIST (368)

RPL_ENDOFWHOWAS (369)

INFO

RPL_INFO (371)

  • Message: "-client- :-string-"
  • Usecase: Sent as a reply to the INFO command, this numeric returns human-readable information describing the server: e.g. its version, list of authors and contributors, and any other miscellaneous information which may be considered to be relevant.

RPL_ENDOFINFO (374)

  • Message: "-client- :End of INFO list"
  • Usecase: Indicates the end of an INFO response.

RPL_MOTDSTART (375)

RPL_MOTD (372)

RPL_ENDOFMOTD (376)

RPL_WHOISHOST (378)

RPL_WHOISMODES (379)

RPL_YOUREOPER (381)

RPL_REHASHING (382)

RPL_TIME (391)

  • Message:

  • Usecase:

    ERR_UNKNOWNERROR (400)

  • Message: "-client- -command-{ -subcommand-} :-info-"
  • Usecase: Indicates that the given command/subcommand could not be processed

ERR_NOSUCHNICK (401)

  • Message: "-client- -nickname- :No such nick/channel"
  • Usecase: Indicates that no client can be found for the supplied nickname.

ERR_NOSUCHSERVER (402)

  • Message: "-client- -server name- :No such server"
  • Usecase: Indicates that the given server name does not exist.

ERR_NOSUCHCHANNEL (403)

  • Message: "-client- -channel- :No such channel"
  • Usecase: Indicates that no channel can be found for the supplied channel name.

ERR_CANNOTSENDTOCHAN (404)

  • Message: "-client- -channel- :Cannot send to channel"

  • Usecase: Indicates that the PRIVMSG / NOTICE could not be delivered to -channel-.

    ERR_TOOMANYCHANNELS (405)

  • Message: "-client- -channel- :You have joined too many channels"
  • Usecase: Indicates that the JOIN command failed because the client has joined their maximum number of channels.

ERR_WASNOSUCHNICK (406)

  • Message: "-client- :There was no such nickname"
  • Usecase: Returned as a reply to WHOWAS to indicate there is no history information for that nickname.

ERR_NOORIGIN (409)

  • Message: "-client- :No origin specified"
  • Usecase: Indicates a PING or PONG message missing the originator parameter which is required by old IRC servers.

ERR_INPUTTOOLONG (417)

  • Message: "-client- :Input line was too long"
  • Usecase: Indicates a given line does not follow the specified size limits (512 bytes for the main section, 4094 or 8191 bytes for the tag section).

ERR_UNKNOWNCOMMAND (421)

  • Message: "-client- -command- :Unknown command"
  • Usecase: Sent to a registered client to indicate that the command they sent isn’t known by the server.

ERR_NOMOTD (422)

  • Message: "-client- :MOTD File is missing"
  • Usecase: Indicates that the Message of the Day file does not exist or could not be found.

ERR_ERRONEUSNICKNAME (432)

  • Message:"-client- -nick- :Erroneus nickname"
  • Usecase: Returned when a NICK command cannot be successfully completed as the desired nickname contains characters that are disallowed by the server.

ERR_NICKNAMEINUSE (433)

  • Message: "-client- -nick- :Nickname is already in use"
  • Usecase: Returned when a NICK command cannot be successfully completed as the desired nickname is already in use

ERR_USERNOTINCHANNEL (441)

  • Message: "-client- -nick- -channel- :They aren't on that channel"
  • Usecase: Returned when a client tries to perform a channel+nick affecting command, when the nick isn’t joined to the channel

ERR_NOTONCHANNEL (442)

  • Message: "-client- -channel- :You're not on that channel"
  • Usecase: Returned when a client tries to perform a channel-affecting command on a channel which the client isn’t a part of.

ERR_USERONCHANNEL (443)

  • Message: "-client- -nick- -channel- :is already on channel"
  • Usecase: Returned when a client tries to invite -nick- to a channel they’re already joined to.

ERR_NOTREGISTERED (451)

  • Message: "-client- :You have not registered"

  • Usecase: Returned when a client command cannot be parsed as they are not yet registered.

    ERR_NEEDMOREPARAMS (461)

  • Message: "-client- -command- :Not enough parameters"
  • Usecase: Returned when a client command cannot be parsed because not enough parameters were supplied.

ERR_ALREADYREGISTERED (462)

  • Message: "-client- :You may not reregister"
  • Usecase: Returned when a client tries to change a detail that can only be set during registration (such as resending the PASS or USER after registration).

ERR_PASSWDMISMATCH (464)

  • Message: "-client- :Password incorrect"
  • Usecase: Returned to indicate that the connection could not be registered as the password was either incorrect or not supplied.

ERR_YOUREBANNEDCREEP (465)

  • Message: "-client- :You are banned from this server."
  • Usecase: Returned to indicate that the server has been configured to explicitly deny connections from this client.

ERR_CHANNELISFULL (471)

  • Message: "-client- -channel- :Cannot join channel (+l)"
  • Usecase: Returned to indicate that a JOIN command failed because the client limit mode has been set and the maximum number of users are already joined to the channel.

ERR_UNKNOWNMODE (472)

  • Message: "-client- -modechar- :is unknown mode char to me"
  • Usecase: Indicates that a mode character used by a client is not recognized by the server. The text used in the last param of this message may vary.

ERR_INVITEONLYCHAN (473)

  • Message: "-client- -channel- :Cannot join channel (+i)"
  • Usecase: Returned to indicate that a JOIN command failed because the channel is set to [invite-only] mode and the client has not been invited to the channel or had an invite exemption set for them.

ERR_BANNEDFROMCHAN (474)

  • Message: "-client- -channel- :Cannot join channel (+b)"

  • Usecase: Returned to indicate that a JOIN command failed because the client has been banned from the channel and has not had a ban exemption set for them. The text used in the last param of this message may vary.

    ERR_BADCHANNELKEY (475)

  • Message: "-client- -channel- :Cannot join channel (+k)"
  • Usecase: Returned to indicate that a JOIN command failed because the channel requires a key and the key was either incorrect or not supplied.

ERR_BADCHANMASK (476)

  • Message: "-channel- :Bad Channel Mask"
  • Usecase: Indicates the supplied channel name is not a valid.This is similar to, but stronger than, ERR_NOSUCHCHANNEL (403), which indicates that the channel does not exist, but that it may be a valid name.

ERR_NOPRIVILEGES (481)

  • Message: "-client- :Permission Denied- You're not an IRC operator"
  • Usecase: Indicates that the command failed because the user is not an IRC operator.

ERR_CHANOPRIVSNEEDED (482)

  • Message: "-client- -channel- :You're not channel operator"
  • Usecase: Indicates that a command failed because the client does not have the appropriate channel privileges.

ERR_CANTKILLSERVER (483)

  • Message: "-client- :You cant kill a server!"
  • Usecase: Indicates that a KILL command failed because the user tried to kill a server.

ERR_NOOPERHOST (491)

  • Message: "-client- :No O-lines for your host"
  • Usecase: Indicates that an OPER command failed because the server has not been configured to allow connections from this client’s host to become an operator.

ERR_UMODEUNKNOWNFLAG (501)

  • Message: "-client- :Unknown MODE flag"
  • Usecase: Indicates that a MODE command affecting a user contained a MODE letter that was not recognized.

ERR_USERSDONTMATCH (502)

  • Message: "-client- :Cant change mode for other users"
  • Usecase: Indicates that a MODE command affecting a user failed because they were trying to set or view modes for other users.

ERR_HELPNOTFOUND (524)

  • Message: "-client- -subject- :No help available on this topic"
  • Usecase: Indicates that a HELP command requested help on a subject the server does not know about.

ERR_INVALIDKEY (525)

  • Message: "-client- -target chan- :Key is not well-formed"
  • Usecase: Indicates the value of a key channel mode change (+k) was rejected.

RPL_STARTTLS (670)

  • Message: "-client- :STARTTLS successful, proceed with TLS handshake"
  • Usecase: This numeric is used by the IRCv3 tls extension and indicates that the client may begin a TLS handshake.

RPL_WHOISSECURE (671)

ERR_STARTTLS (691)

ERR_INVALIDMODEPARAM (696)

  • Message: "-client- -target chan // user- -mode char- -parameter- :-description-"
  • Usecase: Indicates that there was a problem with a mode parameter. Replaces various implementation-specific mode-specific numerics.

RPL_HELPSTART (704)

  • Message: "-client- -subject- :-first line of help section-"
  • Usecase: Indicates the start of a reply to a HELP command.

RPL_HELPTXT (705)

  • Message: "-client- -subject- :-line of help text-"
  • Usecase: Returns a line of HELP text to the client. Lines MAY be wrapped to a certain line length by the server.

RPL_ENDOFHELP (706)

  • Message: "-client- -subject- :-last line of help text-"
  • Usecase: Returns the final HELP line to the client.

ERR_NOPRIVS (723)

  • Message: "-client- -priv- :Insufficient oper privileges."
  • Usecase: Sent by a server to alert an IRC operator that they they do not have the specific operator privilege required by this server/network to perform the command or action they requested.

RPL_LOGGEDIN (900)

  • Message: "-client- -nick-!-user-@-host- -account- :You are now logged in as -username-"
  • Usecase: This numeric indicates that the client was logged into the specified account

RPL_LOGGEDOUT (901)

  • Message: "-client- -nick-!-user-@-host- :You are now logged out"
  • Usecase: This numeric indicates that the client was logged out of their account.

ERR_NICKLOCKED (902)

  • Message: "-client- :You must use a nick assigned to you"
  • Usecase:

RPL_SASLSUCCESS (903)

ERR_SASLFAIL (904)

ERR_SASLTOOLONG (905)

ERR_SASLABORTED (906)

ERR_SASLALREADY (907)

RPL_SASLMECHS (908)