Network Working Group C. Kalt Request for Comments: 2812 April 2000 Updates: 1459 Category: Informational Internet Relay Chat: Client Protocol Status of this Memo This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2000). All Rights Reserved. IESG NOTE: The IRC protocol itself enables several possibilities of transferring data between clients, and just like with other transfer mechanisms like email, the receiver of the data has to be careful about how the data is handled. For more information on security issues with the IRC protocol, see for example http://www.irchelp.org/irchelp/security/. Abstract The IRC (Internet Relay Chat) protocol is for use with text based conferencing; the simplest client being any socket program capable of connecting to the server. This document defines the Client Protocol, and assumes that the reader is familiar with the IRC Architecture [IRC-ARCH]. Table of Contents 1. Labels ..................................................... 3 1.1 Servers ................................................ 3 1.2 Clients ................................................ 3 1.2.1 Users ............................................. 4 1.2.1.1 Operators .................................... 4 1.2.2 Services .......................................... 4 1.3 Channels ............................................... 4 2. The IRC Client Specification ............................... 5 2.1 Overview ............................................... 5 2.2 Character codes ........................................ 5 2.3 Messages ............................................... 5 Kalt Informational [Page 1] RFC 2812 Internet Relay Chat: Client Protocol April 2000 2.3.1 Message format in Augmented BNF ................... 6 2.4 Numeric replies ........................................ 8 2.5 Wildcard expressions ................................... 9 3. Message Details ............................................ 9 3.1 Connection Registration ................................ 10 3.1.1 Password message .................................. 10 3.1.2 Nick message ...................................... 10 3.1.3 User message ...................................... 11 3.1.4 Oper message ...................................... 12 3.1.5 User mode message ................................. 12 3.1.6 Service message ................................... 13 3.1.7 Quit .............................................. 14 3.1.8 Squit ............................................. 15 3.2 Channel operations ..................................... 15 3.2.1 Join message ...................................... 16 3.2.2 Part message ...................................... 17 3.2.3 Channel mode message .............................. 18 3.2.4 Topic message ..................................... 19 3.2.5 Names message ..................................... 20 3.2.6 List message ...................................... 21 3.2.7 Invite message .................................... 21 3.2.8 Kick command ...................................... 22 3.3 Sending messages ....................................... 23 3.3.1 Private messages .................................. 23 3.3.2 Notice ............................................ 24 3.4 Server queries and commands ............................ 25 3.4.1 Motd message ...................................... 25 3.4.2 Lusers message .................................... 25 3.4.3 Version message ................................... 26 3.4.4 Stats message ..................................... 26 3.4.5 Links message ..................................... 27 3.4.6 Time message ...................................... 28 3.4.7 Connect message ................................... 28 3.4.8 Trace message ..................................... 29 3.4.9 Admin command ..................................... 30 3.4.10 Info command ...................................... 31 3.5 Service Query and Commands ............................. 31 3.5.1 Servlist message .................................. 31 3.5.2 Squery ............................................ 32 3.6 User based queries ..................................... 32 3.6.1 Who query ......................................... 32 3.6.2 Whois query ....................................... 33 3.6.3 Whowas ............................................ 34 3.7 Miscellaneous messages ................................. 34 3.7.1 Kill message ...................................... 35 3.7.2 Ping message ...................................... 36 3.7.3 Pong message ...................................... 37 3.7.4 Error ............................................. 37 Kalt Informational [Page 2] RFC 2812 Internet Relay Chat: Client Protocol April 2000 4. Optional features .......................................... 38 4.1 Away ................................................... 38 4.2 Rehash message ......................................... 39 4.3 Die message ............................................ 39 4.4 Restart message ........................................ 40 4.5 Summon message ......................................... 40 4.6 Users .................................................. 41 4.7 Operwall message ....................................... 41 4.8 Userhost message ....................................... 42 4.9 Ison message ........................................... 42 5. Replies .................................................... 43 5.1 Command responses ...................................... 43 5.2 Error Replies .......................................... 53 5.3 Reserved numerics ...................................... 59 6. Current implementations .................................... 60 7. Current problems ........................................... 60 7.1 Nicknames .............................................. 60 7.2 Limitation of wildcards ................................ 61 7.3 Security considerations ................................ 61 8. Current support and availability ........................... 61 9. Acknowledgements ........................................... 61 10. References ................................................ 62 11. Author's Address .......................................... 62 12. Full Copyright Statement .................................. 63 1. Labels This section defines the identifiers used for the various components of the IRC protocol. 1.1 Servers Servers are uniquely identified by their name, which has a maximum length of sixty three (63) characters. See the protocol grammar rules (section 2.3.1) for what may and may not be used in a server name. 1.2 Clients For each client all servers MUST have the following information: a netwide unique identifier (whose format depends on the type of client) and the server which introduced the client. Kalt Informational [Page 3] RFC 2812 Internet Relay Chat: Client Protocol April 2000 1.2.1 Users Each user is distinguished from other users by a unique nickname having a maximum length of nine (9) characters. See the protocol grammar rules (section 2.3.1) for what may and may not be used in a nickname. While the maximum length is limited to nine characters, clients SHOULD accept longer strings as they may become used in future evolutions of the protocol. 1.2.1.1 Operators To allow a reasonable amount of order to be kept within the IRC network, a special class of users (operators) is allowed to perform general maintenance functions on the network. Although the powers granted to an operator can be considered as 'dangerous', they are nonetheless often necessary. Operators SHOULD be able to perform basic network tasks such as disconnecting and reconnecting servers as needed. In recognition of this need, the protocol discussed herein provides for operators only to be able to perform such functions. See sections 3.1.8 (SQUIT) and 3.4.7 (CONNECT). A more controversial power of operators is the ability to remove a user from the connected network by 'force', i.e., operators are able to close the connection between any client and server. The justification for this is very delicate since its abuse is both destructive and annoying, and its benefits close to inexistent. For further details on this type of action, see section 3.7.1 (KILL). 1.2.2 Services Each service is distinguished from other services by a service name composed of a nickname and a server name. As for users, the nickname has a maximum length of nine (9) characters. See the protocol grammar rules (section 2.3.1) for what may and may not be used in a nickname. 1.3 Channels Channels names are strings (beginning with a '&', '#', '+' or '!' character) of length up to fifty (50) characters. Apart from the requirement that the first character is either '&', '#', '+' or '!', the only restriction on a channel name is that it SHALL NOT contain any spaces (' '), a control G (^G or ASCII 7), a comma (','). Space is used as parameter separator and command is used as a list item separator by the protocol). A colon (':') can also be used as a delimiter for the channel mask. Channel names are case insensitive. Kalt Informational [Page 4] RFC 2812 Internet Relay Chat: Client Protocol April 2000 See the protocol grammar rules (section 2.3.1) for the exact syntax of a channel name. Each prefix characterizes a different channel type. The definition of the channel types is not relevant to the client-server protocol and thus it is beyond the scope of this document. More details can be found in "Internet Relay Chat: Channel Management" [IRC-CHAN]. 2. The IRC Client Specification 2.1 Overview The protocol as described herein is for use only with client to server connections when the client registers as a user. 2.2 Character codes No specific character set is specified. The protocol is based on a set of codes which are composed of eight (8) bits, making up an octet. Each message may be composed of any number of these octets; however, some octet values are used for control codes, which act as message delimiters. Regardless of being an 8-bit protocol, the delimiters and keywords are such that protocol is mostly usable from US-ASCII terminal and a telnet connection. Because of IRC's Scandinavian origin, the characters {}|^ are considered to be the lower case equivalents of the characters []\~, respectively. This is a critical issue when determining the equivalence of two nicknames or channel names. 2.3 Messages Servers and clients send each other messages, which may or may not generate a reply. If the message contains a valid command, as described in later sections, the client should expect a reply as specified but it is not advised to wait forever for the reply; client to server and server to server communication is essentially asynchronous by nature. Each IRC message may consist of up to three main parts: the prefix (OPTIONAL), the command, and the command parameters (maximum of fifteen (15)). The prefix, command, and all parameters are separated by one ASCII space character (0x20) each. Kalt Informational [Page 5] RFC 2812 Internet Relay Chat: Client Protocol April 2000 The presence of a prefix is indicated with a single leading ASCII colon character (':', 0x3b), which MUST be the first character of the message itself. There MUST be NO gap (whitespace) between the colon and the prefix. The prefix is used by servers to indicate the true origin of the message. If the prefix is missing from the message, it is assumed to have originated from the connection from which it was received from. Clients SHOULD NOT use a prefix when sending a message; if they use one, the only valid prefix is the registered nickname associated with the client. The command MUST either be a valid IRC command or a three (3) digit number represented in ASCII text. IRC messages are always lines of characters terminated with a CR-LF (Carriage Return - Line Feed) pair, and these messages SHALL NOT exceed 512 characters in length, counting all characters including the trailing CR-LF. Thus, there are 510 characters maximum allowed for the command and its parameters. There is no provision for continuation of message lines. See section 6 for more details about current implementations. 2.3.1 Message format in Augmented BNF The protocol messages must be extracted from the contiguous stream of octets. The current solution is to designate two characters, CR and LF, as message separators. Empty messages are silently ignored, which permits use of the sequence CR-LF between messages without extra problems. The extracted message is parsed into the components , and list of parameters (). The Augmented BNF representation for this is: message = [ ":" prefix SPACE ] command [ params ] crlf prefix = servername / ( nickname [ [ "!" user ] "@" host ] ) command = 1*letter / 3digit params = *14( SPACE middle ) [ SPACE ":" trailing ] =/ 14( SPACE middle ) [ SPACE [ ":" ] trailing ] nospcrlfcl = %x01-09 / %x0B-0C / %x0E-1F / %x21-39 / %x3B-FF ; any octet except NUL, CR, LF, " " and ":" middle = nospcrlfcl *( ":" / nospcrlfcl ) trailing = *( ":" / " " / nospcrlfcl ) SPACE = %x20 ; space character crlf = %x0D %x0A ; "carriage return" "linefeed" Kalt Informational [Page 6] RFC 2812 Internet Relay Chat: Client Protocol April 2000 NOTES: 1) After extracting the parameter list, all parameters are equal whether matched by or . is just a syntactic trick to allow SPACE within the parameter. 2) The NUL (%x00) character is not special in message framing, and basically could end up inside a parameter, but it would cause extra complexities in normal C string handling. Therefore, NUL is not allowed within messages. Most protocol messages specify additional semantics and syntax for the extracted parameter strings dictated by their position in the list. For example, many server commands will assume that the first parameter after the command is the list of targets, which can be described with: target = nickname / server msgtarget = msgto *( "," msgto ) msgto = channel / ( user [ "%" host ] "@" servername ) msgto =/ ( user "%" host ) / targetmask msgto =/ nickname / ( nickname "!" user "@" host ) channel = ( "#" / "+" / ( "!" channelid ) / "&" ) chanstring [ ":" chanstring ] servername = hostname host = hostname / hostaddr hostname = shortname *( "." shortname ) shortname = ( letter / digit ) *( letter / digit / "-" ) *( letter / digit ) ; as specified in RFC 1123 [HNAME] hostaddr = ip4addr / ip6addr ip4addr = 1*3digit "." 1*3digit "." 1*3digit "." 1*3digit ip6addr = 1*hexdigit 7( ":" 1*hexdigit ) ip6addr =/ "0:0:0:0:0:" ( "0" / "FFFF" ) ":" ip4addr nickname = ( letter / special ) *8( letter / digit / special / "-" ) targetmask = ( "$" / "#" ) mask ; see details on allowed masks in section 3.3.1 chanstring = %x01-07 / %x08-09 / %x0B-0C / %x0E-1F / %x21-2B chanstring =/ %x2D-39 / %x3B-FF ; any octet except NUL, BELL, CR, LF, " ", "," and ":" channelid = 5( %x41-5A / digit ) ; 5( A-Z / 0-9 ) Kalt Informational [Page 7] RFC 2812 Internet Relay Chat: Client Protocol April 2000 Other parameter syntaxes are: user = 1*( %x01-09 / %x0B-0C / %x0E-1F / %x21-3F / %x41-FF ) ; any octet except NUL, CR, LF, " " and "@" key = 1*23( %x01-05 / %x07-08 / %x0C / %x0E-1F / %x21-7F ) ; any 7-bit US_ASCII character, ; except NUL, CR, LF, FF, h/v TABs, and " " letter = %x41-5A / %x61-7A ; A-Z / a-z digit = %x30-39 ; 0-9 hexdigit = digit / "A" / "B" / "C" / "D" / "E" / "F" special = %x5B-60 / %x7B-7D ; "[", "]", "\", "`", "_", "^", "{", "|", "}" NOTES: 1) The syntax is given here for the sole purpose of indicating the format to follow for IP addresses. This reflects the fact that the only available implementations of this protocol uses TCP/IP as underlying network protocol but is not meant to prevent other protocols to be used. 2) has a maximum length of 63 characters. This is a limitation of the protocol as internet hostnames (in particular) can be longer. Such restriction is necessary because IRC messages are limited to 512 characters in length. Clients connecting from a host which name is longer than 63 characters are registered using the host (numeric) address instead of the host name. 3) Some parameters used in the following sections of this documents are not defined here as there is nothing specific about them besides the name that is used for convenience. These parameters follow the general syntax defined for . 2.4 Numeric replies Most of the messages sent to the server generate a reply of some sort. The most common reply is the numeric reply, used for both errors and normal replies. The numeric reply MUST be sent as one message consisting of the sender prefix, the three-digit numeric, and the target of the reply. A numeric reply is not allowed to originate from a client. In all other respects, a numeric reply is just like a normal message, except that the keyword is made up of 3 numeric digits rather than a string of letters. A list of different replies is supplied in section 5 (Replies). Kalt Informational [Page 8] RFC 2812 Internet Relay Chat: Client Protocol April 2000 2.5 Wildcard expressions When wildcards are allowed in a string, it is referred as a "mask". For string matching purposes, the protocol allows the use of two special characters: '?' (%x3F) to match one and only one character, and '*' (%x2A) to match any number of any characters. These two characters can be escaped using the character '\' (%x5C). The Augmented BNF syntax for this is: mask = *( nowild / noesc wildone / noesc wildmany ) wildone = %x3F wildmany = %x2A nowild = %x01-29 / %x2B-3E / %x40-FF ; any octet except NUL, "*", "?" noesc = %x01-5B / %x5D-FF ; any octet except NUL and "\" matchone = %x01-FF ; matches wildone matchmany = *matchone ; matches wildmany Examples: a?c ; Matches any string of 3 characters in length starting with "a" and ending with "c" a*c ; Matches any string of at least 2 characters in length starting with "a" and ending with "c" 3. Message Details On the following pages there are descriptions of each message recognized by the IRC server and client. All commands described in this section MUST be implemented by any server for this protocol. Where the reply ERR_NOSUCHSERVER is returned, it means that the target of the message could not be found. The server MUST NOT send any other replies after this error for that command. The server to which a client is connected is required to parse the complete message, and return any appropriate errors. If multiple parameters is presented, then each MUST be checked for validity and appropriate responses MUST be sent back to the client. In the case of incorrect messages which use parameter lists with comma as an item separator, a reply MUST be sent for each item. Kalt Informational [Page 9] RFC 2812 Internet Relay Chat: Client Protocol April 2000 3.1 Connection Registration The commands described here are used to register a connection with an IRC server as a user as well as to correctly disconnect. A "PASS" command is not required for a client connection to be registered, but it MUST precede the latter of the NICK/USER combination (for a user connection) or the SERVICE command (for a service connection). The RECOMMENDED order for a client to register is as follows: 1. Pass message 2. Nick message 2. Service message 3. User message Upon success, the client will receive an RPL_WELCOME (for users) or RPL_YOURESERVICE (for services) message indicating that the connection is now registered and known the to the entire IRC network. The reply message MUST contain the full client identifier upon which it was registered. 3.1.1 Password message Command: PASS Parameters: The PASS command is used to set a 'connection password'. The optional password can and MUST be set before any attempt to register the connection is made. Currently this requires that user send a PASS command before sending the NICK/USER combination. Numeric Replies: ERR_NEEDMOREPARAMS ERR_ALREADYREGISTRED Example: PASS secretpasswordhere 3.1.2 Nick message Command: NICK Parameters: NICK command is used to give user a nickname or change the existing one. Kalt Informational [Page 10] RFC 2812 Internet Relay Chat: Client Protocol April 2000 Numeric Replies: ERR_NONICKNAMEGIVEN ERR_ERRONEUSNICKNAME ERR_NICKNAMEINUSE ERR_NICKCOLLISION ERR_UNAVAILRESOURCE ERR_RESTRICTED Examples: NICK Wiz ; Introducing new nick "Wiz" if session is still unregistered, or user changing his nickname to "Wiz" :WiZ!jto@tolsun.oulu.fi NICK Kilroy ; Server telling that WiZ changed his nickname to Kilroy. 3.1.3 User message Command: USER Parameters: The USER command is used at the beginning of connection to specify the username, hostname and realname of a new user. The parameter should be a numeric, and can be used to automatically set user modes when registering with the server. This parameter is a bitmask, with only 2 bits having any signification: if the bit 2 is set, the user mode 'w' will be set and if the bit 3 is set, the user mode 'i' will be set. (See Section 3.1.5 "User Modes"). The may contain space characters. Numeric Replies: ERR_NEEDMOREPARAMS ERR_ALREADYREGISTRED Example: USER guest 0 * :Ronnie Reagan ; User registering themselves with a username of "guest" and real name "Ronnie Reagan". USER guest 8 * :Ronnie Reagan ; User registering themselves with a username of "guest" and real name "Ronnie Reagan", and asking to be set invisible. Kalt Informational [Page 11] RFC 2812 Internet Relay Chat: Client Protocol April 2000 3.1.4 Oper message Command: OPER Parameters: A normal user uses the OPER command to obtain operator privileges. The combination of and are REQUIRED to gain Operator privileges. Upon success, the user will receive a MODE message (see section 3.1.5) indicating the new user modes. Numeric Replies: ERR_NEEDMOREPARAMS RPL_YOUREOPER ERR_NOOPERHOST ERR_PASSWDMISMATCH Example: OPER foo bar ; Attempt to register as an operator using a username of "foo" and "bar" as the password. 3.1.5 User mode message Command: MODE Parameters: *( ( "+" / "-" ) *( "i" / "w" / "o" / "O" / "r" ) ) The user MODE's are typically changes which affect either how the client is seen by others or what 'extra' messages the client is sent. A user MODE command MUST only be accepted if both the sender of the message and the nickname given as a parameter are both the same. If no other parameter is given, then the server will return the current settings for the nick. The available modes are as follows: a - user is flagged as away; i - marks a users as invisible; w - user receives wallops; r - restricted user connection; o - operator flag; O - local operator flag; s - marks a user for receipt of server notices. Additional modes may be available later on. Kalt Informational [Page 12] RFC 2812 Internet Relay Chat: Client Protocol April 2000 The flag 'a' SHALL NOT be toggled by the user using the MODE command, instead use of the AWAY command is REQUIRED. If a user attempts to make themselves an operator using the "+o" or "+O" flag, the attempt SHOULD be ignored as users could bypass the authentication mechanisms of the OPER command. There is no restriction, however, on anyone `deopping' themselves (using "-o" or "-O"). On the other hand, if a user attempts to make themselves unrestricted using the "-r" flag, the attempt SHOULD be ignored. There is no restriction, however, on anyone `deopping' themselves (using "+r"). This flag is typically set by the server upon connection for administrative reasons. While the restrictions imposed are left up to the implementation, it is typical that a restricted user not be allowed to change nicknames, nor make use of the channel operator status on channels. The flag 's' is obsolete but MAY still be used. Numeric Replies: ERR_NEEDMOREPARAMS ERR_USERSDONTMATCH ERR_UMODEUNKNOWNFLAG RPL_UMODEIS Examples: MODE WiZ -w ; Command by WiZ to turn off reception of WALLOPS messages. MODE Angel +i ; Command from Angel to make herself invisible. MODE WiZ -o ; WiZ 'deopping' (removing operator status). 3.1.6 Service message Command: SERVICE Parameters: The SERVICE command to register a new service. Command parameters specify the service nickname, distribution, type and info of a new service. Kalt Informational [Page 13] RFC 2812 Internet Relay Chat: Client Protocol April 2000 The parameter is used to specify the visibility of a service. The service may only be known to servers which have a name matching the distribution. For a matching server to have knowledge of the service, the network path between that server and the server on which the service is connected MUST be composed of servers which names all match the mask. The parameter is currently reserved for future usage. Numeric Replies: ERR_ALREADYREGISTRED ERR_NEEDMOREPARAMS ERR_ERRONEUSNICKNAME RPL_YOURESERVICE RPL_YOURHOST RPL_MYINFO Example: SERVICE dict * *.fr 0 0 :French Dictionary ; Service registering itself with a name of "dict". This service will only be available on servers which name matches "*.fr". 3.1.7 Quit Command: QUIT Parameters: [ ] A client session is terminated with a quit message. The server acknowledges this by sending an ERROR message to the client. Numeric Replies: None. Example: QUIT :Gone to have lunch ; Preferred message format. :syrk!kalt@millennium.stealth.net QUIT :Gone to have lunch ; User syrk has quit IRC to have lunch. Kalt Informational [Page 14] RFC 2812 Internet Relay Chat: Client Protocol April 2000 3.1.8 Squit Command: SQUIT Parameters: The SQUIT command is available only to operators. It is used to disconnect server links. Also servers can generate SQUIT messages on error conditions. A SQUIT message may also target a remote server connection. In this case, the SQUIT message will simply be sent to the remote server without affecting the servers in between the operator and the remote server. The SHOULD be supplied by all operators who execute a SQUIT for a remote server. The server ordered to disconnect its peer generates a WALLOPS message with included, so that other users may be aware of the reason of this action. Numeric replies: ERR_NOPRIVILEGES ERR_NOSUCHSERVER ERR_NEEDMOREPARAMS Examples: SQUIT tolsun.oulu.fi :Bad Link ? ; Command to uplink of the server tolson.oulu.fi to terminate its connection with comment "Bad Link". :Trillian SQUIT cm22.eng.umd.edu :Server out of control ; Command from Trillian from to disconnect "cm22.eng.umd.edu" from the net with comment "Server out of control". 3.2 Channel operations This group of messages is concerned with manipulating channels, their properties (channel modes), and their contents (typically users). For this reason, these messages SHALL NOT be made available to services. All of these messages are requests which will or will not be granted by the server. The server MUST send a reply informing the user whether the request was granted, denied or generated an error. When the server grants the request, the message is typically sent back (eventually reformatted) to the user with the prefix set to the user itself. Kalt Informational [Page 15] RFC 2812 Internet Relay Chat: Client Protocol April 2000 The rules governing how channels are managed are enforced by the servers. These rules are beyond the scope of this document. More details are found in "Internet Relay Chat: Channel Management" [IRC- CHAN]. 3.2.1 Join message Command: JOIN Parameters: ( *( "," ) [ *( "," ) ] ) / "0" The JOIN command is used by a user to request to start listening to the specific channel. Servers MUST be able to parse arguments in the form of a list of target, but SHOULD NOT use lists when sending JOIN messages to clients. Once a user has joined a channel, he receives information about all commands his server receives affecting the channel. This includes JOIN, MODE, KICK, PART, QUIT and of course PRIVMSG/NOTICE. This allows channel members to keep track of the other channel members, as well as channel modes. If a JOIN is successful, the user receives a JOIN message as confirmation and is then sent the channel's topic (using RPL_TOPIC) and the list of users who are on the channel (using RPL_NAMREPLY), which MUST include the user joining. Note that this message accepts a special argument ("0"), which is a special request to leave all channels the user is currently a member of. The server will process this message as if the user had sent a PART command (See Section 3.2.2) for each channel he is a member of. Numeric Replies: ERR_NEEDMOREPARAMS ERR_BANNEDFROMCHAN ERR_INVITEONLYCHAN ERR_BADCHANNELKEY ERR_CHANNELISFULL ERR_BADCHANMASK ERR_NOSUCHCHANNEL ERR_TOOMANYCHANNELS ERR_TOOMANYTARGETS ERR_UNAVAILRESOURCE RPL_TOPIC Examples: JOIN #foobar ; Command to join channel #foobar. JOIN &foo fubar ; Command to join channel &foo using key "fubar". Kalt Informational [Page 16] RFC 2812 Internet Relay Chat: Client Protocol April 2000 JOIN #foo,&bar fubar ; Command to join channel #foo using key "fubar" and &bar using no key. JOIN #foo,#bar fubar,foobar ; Command to join channel #foo using key "fubar", and channel #bar using key "foobar". JOIN #foo,#bar ; Command to join channels #foo and #bar. JOIN 0 ; Leave all currently joined channels. :WiZ!jto@tolsun.oulu.fi JOIN #Twilight_zone ; JOIN message from WiZ on channel #Twilight_zone 3.2.2 Part message Command: PART Parameters: *( "," ) [ ] The PART command causes the user sending the message to be removed from the list of active members for all given channels listed in the parameter string. If a "Part Message" is given, this will be sent instead of the default message, the nickname. This request is always granted by the server. Servers MUST be able to parse arguments in the form of a list of target, but SHOULD NOT use lists when sending PART messages to clients. Numeric Replies: ERR_NEEDMOREPARAMS ERR_NOSUCHCHANNEL ERR_NOTONCHANNEL Examples: PART #twilight_zone ; Command to leave channel "#twilight_zone" PART #oz-ops,&group5 ; Command to leave both channels "&group5" and "#oz-ops". :WiZ!jto@tolsun.oulu.fi PART #playzone :I lost ; User WiZ leaving channel "#playzone" with the message "I lost". Kalt Informational [Page 17] RFC 2812 Internet Relay Chat: Client Protocol April 2000 3.2.3 Channel mode message Command: MODE Parameters: *( ( "-" / "+" ) * * ) The MODE command is provided so that users may query and change the characteristics of a channel. For more details on available modes and their uses, see "Internet Relay Chat: Channel Management" [IRC- CHAN]. Note that there is a maximum limit of three (3) changes per command for modes that take a parameter. Numeric Replies: ERR_NEEDMOREPARAMS ERR_KEYSET ERR_NOCHANMODES ERR_CHANOPRIVSNEEDED ERR_USERNOTINCHANNEL ERR_UNKNOWNMODE RPL_CHANNELMODEIS RPL_BANLIST RPL_ENDOFBANLIST RPL_EXCEPTLIST RPL_ENDOFEXCEPTLIST RPL_INVITELIST RPL_ENDOFINVITELIST RPL_UNIQOPIS The following examples are given to help understanding the syntax of the MODE command, but refer to modes defined in "Internet Relay Chat: Channel Management" [IRC-CHAN]. Examples: MODE #Finnish +imI *!*@*.fi ; Command to make #Finnish channel moderated and 'invite-only' with user with a hostname matching *.fi automatically invited. MODE #Finnish +o Kilroy ; Command to give 'chanop' privileges to Kilroy on channel #Finnish. MODE #Finnish +v Wiz ; Command to allow WiZ to speak on #Finnish. MODE #Fins -s ; Command to remove 'secret' flag from channel #Fins. MODE #42 +k oulu ; Command to set the channel key to "oulu". MODE #42 -k oulu ; Command to remove the "oulu" channel key on channel "#42". Kalt Informational [Page 18] RFC 2812 Internet Relay Chat: Client Protocol April 2000 MODE #eu-opers +l 10 ; Command to set the limit for the number of users on channel "#eu-opers" to 10. :WiZ!jto@tolsun.oulu.fi MODE #eu-opers -l ; User "WiZ" removing the limit for the number of users on channel "#eu- opers". MODE &oulu +b ; Command to list ban masks set for the channel "&oulu". MODE &oulu +b *!*@* ; Command to prevent all users from joining. MODE &oulu +b *!*@*.edu +e *!*@*.bu.edu ; Command to prevent any user from a hostname matching *.edu from joining, except if matching *.bu.edu MODE #bu +be *!*@*.edu *!*@*.bu.edu ; Comment to prevent any user from a hostname matching *.edu from joining, except if matching *.bu.edu MODE #meditation e ; Command to list exception masks set for the channel "#meditation". MODE #meditation I ; Command to list invitations masks set for the channel "#meditation". MODE !12345ircd O ; Command to ask who the channel creator for "!12345ircd" is 3.2.4 Topic message Command: TOPIC Parameters: [ ] The TOPIC command is used to change or view the topic of a channel. The topic for channel is returned if there is no given. If the parameter is present, the topic for that channel will be changed, if this action is allowed for the user requesting it. If the parameter is an empty string, the topic for that channel will be removed. Kalt Informational [Page 19] RFC 2812 Internet Relay Chat: Client Protocol April 2000 Numeric Replies: ERR_NEEDMOREPARAMS ERR_NOTONCHANNEL RPL_NOTOPIC RPL_TOPIC ERR_CHANOPRIVSNEEDED ERR_NOCHANMODES Examples: :WiZ!jto@tolsun.oulu.fi TOPIC #test :New topic ; User Wiz setting the topic. TOPIC #test :another topic ; Command to set the topic on #test to "another topic". TOPIC #test : ; Command to clear the topic on #test. TOPIC #test ; Command to check the topic for #test. 3.2.5 Names message Command: NAMES Parameters: [ *( "," ) [ ] ] By using the NAMES command, a user can list all nicknames that are visible to him. For more details on what is visible and what is not, see "Internet Relay Chat: Channel Management" [IRC-CHAN]. The parameter specifies which channel(s) to return information about. There is no error reply for bad channel names. If no parameter is given, a list of all channels and their occupants is returned. At the end of this list, a list of users who are visible but either not on any channel or not on a visible channel are listed as being on `channel' "*". If the parameter is specified, the request is forwarded to that server which will generate the reply. Wildcards are allowed in the parameter. Numerics: ERR_TOOMANYMATCHES ERR_NOSUCHSERVER RPL_NAMREPLY RPL_ENDOFNAMES Kalt Informational [Page 20] RFC 2812 Internet Relay Chat: Client Protocol April 2000 Examples: NAMES #twilight_zone,#42 ; Command to list visible users on #twilight_zone and #42 NAMES ; Command to list all visible channels and users 3.2.6 List message Command: LIST Parameters: [ *( "," ) [ ] ] The list command is used to list channels and their topics. If the parameter is used, only the status of that channel is displayed. If the parameter is specified, the request is forwarded to that server which will generate the reply. Wildcards are allowed in the parameter. Numeric Replies: ERR_TOOMANYMATCHES ERR_NOSUCHSERVER RPL_LIST RPL_LISTEND Examples: LIST ; Command to list all channels. LIST #twilight_zone,#42 ; Command to list channels #twilight_zone and #42 3.2.7 Invite message Command: INVITE Parameters: The INVITE command is used to invite a user to a channel. The parameter is the nickname of the person to be invited to the target channel . There is no requirement that the channel the target user is being invited to must exist or be a valid channel. However, if the channel exists, only members of the channel are allowed to invite other users. When the channel has invite-only flag set, only channel operators may issue INVITE command. Kalt Informational [Page 21] RFC 2812 Internet Relay Chat: Client Protocol April 2000 Only the user inviting and the user being invited will receive notification of the invitation. Other channel members are not notified. (This is unlike the MODE changes, and is occasionally the source of trouble for users.) Numeric Replies: ERR_NEEDMOREPARAMS ERR_NOSUCHNICK ERR_NOTONCHANNEL ERR_USERONCHANNEL ERR_CHANOPRIVSNEEDED RPL_INVITING RPL_AWAY Examples: :Angel!wings@irc.org INVITE Wiz #Dust ; Message to WiZ when he has been invited by user Angel to channel #Dust INVITE Wiz #Twilight_Zone ; Command to invite WiZ to #Twilight_zone 3.2.8 Kick command Command: KICK Parameters: *( "," ) *( "," ) [] The KICK command can be used to request the forced removal of a user from a channel. It causes the to PART from the by force. For the message to be syntactically correct, there MUST be either one channel parameter and multiple user parameter, or as many channel parameters as there are user parameters. If a "comment" is given, this will be sent instead of the default message, the nickname of the user issuing the KICK. The server MUST NOT send KICK messages with multiple channels or users to clients. This is necessarily to maintain backward compatibility with old client software. Numeric Replies: ERR_NEEDMOREPARAMS ERR_NOSUCHCHANNEL ERR_BADCHANMASK ERR_CHANOPRIVSNEEDED ERR_USERNOTINCHANNEL ERR_NOTONCHANNEL Kalt Informational [Page 22] RFC 2812 Internet Relay Chat: Client Protocol April 2000 Examples: KICK &Melbourne Matthew ; Command to kick Matthew from &Melbourne KICK #Finnish John :Speaking English ; Command to kick John from #Finnish using "Speaking English" as the reason (comment). :WiZ!jto@tolsun.oulu.fi KICK #Finnish John ; KICK message on channel #Finnish from WiZ to remove John from channel 3.3 Sending messages The main purpose of the IRC protocol is to provide a base for clients to communicate with each other. PRIVMSG, NOTICE and SQUERY (described in Section 3.5 on Service Query and Commands) are the only messages available which actually perform delivery of a text message from one client to another - the rest just make it possible and try to ensure it happens in a reliable and structured manner. 3.3.1 Private messages Command: PRIVMSG Parameters: PRIVMSG is used to send private messages between users, as well as to send messages to channels. is usually the nickname of the recipient of the message, or a channel name. The parameter may also be a host mask (#) or server mask ($). In both cases the server will only send the PRIVMSG to those who have a server or host matching the mask. The mask MUST have at least 1 (one) "." in it and no wildcards following the last ".". This requirement exists to prevent people sending messages to "#*" or "$*", which would broadcast to all users. Wildcards are the '*' and '?' characters. This extension to the PRIVMSG command is only available to operators. Numeric Replies: ERR_NORECIPIENT ERR_NOTEXTTOSEND ERR_CANNOTSENDTOCHAN ERR_NOTOPLEVEL ERR_WILDTOPLEVEL ERR_TOOMANYTARGETS ERR_NOSUCHNICK RPL_AWAY Kalt Informational [Page 23] RFC 2812 Internet Relay Chat: Client Protocol April 2000 Examples: :Angel!wings@irc.org PRIVMSG Wiz :Are you receiving this message ? ; Message from Angel to Wiz. PRIVMSG Angel :yes I'm receiving it !