2 ngIRCd - Next Generation IRC Server
4 (c)2001-2008 Alexander Barton,
5 alex@barton.de, http://www.barton.de/
7 ngIRCd is free software and published under the
8 terms of the GNU General Public License.
16 The ngIRCd implements the Internet Relay Chat (IRC) protocol version 2.10
17 as defined in RFC ("request for comment") 1459 and 2810-2813. These (and
18 probably further relevant RFCs) are listed in doc/RFC.txt.
20 Unfortunately, even the "original" ircd doesn't follow these specifications
21 in all details. But because the ngIRCd should be a fully compatible
22 replacement for this server ("ircd") it tries to emulate these differences.
24 If you don't like this behavior please ./configure the ngIRCd using the
25 "--enable-strict-rfc" command line option. But keep in mind: not all IRC
26 clients are compatible with a server configured that way, some can't even
27 connect at all! Therefore this option usually isn't desired for "normal
34 Starting with version 0.5.0, the ngIRCd extends the original IRC protocol
35 as defined in RFC 2810-2813. This enhanced protocol is named "IRC+". It is
36 backwards compatible to the "plain" IRC protocol and will only be used by
37 the ngIRCd if it detects that the peer supports it as well.
39 The "PASS" command is used to detect the protocol and peer versions see
40 RFC 2813 (section 4.1.1) and below.
43 II.1 Register new server link
46 Parameters: <password> <version> <flags> [<options>]
47 Used by: servers only (with these parameters)
49 <password> is the password for this new server link as defined in the server
50 configuration which is sent to the peer or received from it.
52 <version> consists of two parts and is at least 4, at most 14 characters
53 long: the first four bytes contain the IRC protocol version number, whereas
54 the first two bytes represent the major version, the last two bytes the
55 minor version (the string "0210" indicates version 2.10, e.g.).
57 The following optional(!) 10 bytes contain an implementation-dependent
58 version number. Servers supporting the IRC+ protocol as defined in this
59 document provide the string "-IRC+" here.
61 Example for <version>: "0210-IRC+".
63 <flags> consists of two parts separated with the character "|" and is at
64 most 100 bytes long. The first part contains the name of the implementation
65 (ngIRCd sets this to "ngircd", the original ircd to "IRC", e.g.). The second
66 part is implementation-dependent and should only be parsed if the peer
67 supports the IRC+ protocol as well. In this case the following syntax is
68 used: "<serverversion>[:<serverflags>]".
70 <serverversion> is an ASCII representation of the clear-text server version
71 number, <serverflags> indicates the supported IRC+ protocol extensions (and
74 The following <serverflags> are defined at the moment:
76 - C: The server supports the CHANINFO command.
78 - L: INVITE- and BAN-lists should be synchronized between servers: if the
79 peer understands this flag, it will send "MODE +I" and "MODE +b"
80 commands after the server link has been established.
82 - H: The server supports the "enhanced server handshake", see section II.2
83 for a detailed description.
85 - o: IRC operators are allowed to change channel- and channel-user-modes
86 even if they aren't channel-operator of the affected channel.
88 - S: The server supports the SERVICE command (on this link).
90 - Z: Compressed server links are supported by the server.
92 Example for a complete <flags> string: "ngircd|0.7.5:CZ".
94 The optional parameter <options> is used to propagate server options as
95 defined in RFC 2813, section 4.1.1.
98 II.2 Enhanced Server Handshake
100 The "enhanced server handshake" is used when both servers support this IRC+
101 extension, which is indicated by the 'H' flag in the <serverflags> sent with
102 the PASS command, see section II.1.
104 It basically means, that after exchanging the PASS and SERVER commands the
105 server is not registered in the network (as usual), but that IRC numerics
106 are exchanged until the numeric 376 (ENDOFMOTD) is received. Afterwards the
107 peer is registered in the network as with the regular IRC protocol.
109 A server implementing the enhanced server handshake (and indicating this
110 using 'H' in the <serverflags>) MUST ignore all unknown numerics to it
113 In addition, such a server should at least send the numeric 005 (ISUPPORT)
114 to its peer, containing the following information. Syntax: <key>=<value>,
115 one token per IRC parameter. If the server has to send more than 12 token
116 it must send separate ISUPPORT numerics (this is a limitation of the IRC
117 protocol which allows at max 15 arguments per command).
119 - NICKLEN: Maximum nickname length. Default: 9.
120 - CASEMAPPING: Case mapping used for nick- and channel name comparing.
121 Default: "ascii", the chars [a-z] are lowercase of [A-Z].
122 - PREFIX: List of channel modes a person can get and the respective prefix
123 a channel or nickname will get in case the person has it. The order of the
124 modes goes from most powerful to least powerful. Default: "(ov)@+"
125 - CHANTYPES: Supported channel prefixes. Default: "#".
126 - CHANMODES: List of channel modes for 4 types, separated by comma (","):
127 Mode that adds or removes a nick or address to a list, mode that changes
128 a setting (both have always has a parameter), mode that changes a setting
129 and only has a parameter when set, and mode that changes a setting and
130 never has a parameter. For example "bI,k,l,imnPst".
131 - CHANLIMIT: Maximum number of channels allowed to join by channel prefix,
134 Please see <http://www.irc.org/tech_docs/005.html> for details.
136 The information exchanged using ISUPPORT can be used to detect configuration
137 incompatibilities (different maximum nick name length, for example) and
138 therefore to disconnect the peer prior to registering it in the network.
141 II.3 Exchange channel-modes, topics, and persistent channels
144 Parameters: <channel> +<modes> <key> <limit> [<topic>]
145 Used by: servers only
147 CHANINFO is used by servers to inform each other about a channel: its
148 modes, channel key, user limits and its topic. <topic> is optional.
150 If the channel already exists on the server receiving the CHANINFO command,
151 it only adopts the <modes> (or the <topic>) if there are no modes (or topic)
152 already set. It there are already values set the server ignores the
153 corresponding parameter.
155 If the channel doesn't exists at all it will be created.
157 The parameter <key> must be ignored if a channel has no key (the parameter
158 <modes> doesn't list the "k" channel mode). In this case <key> should
159 contain "*" because the parameter <key> is required by the CHANINFO syntax
160 and therefore can't be omitted. The parameter <limit> must be ignored when
161 a channel has no user limit (the parameter <modes> doesn't list the "l"
162 channel mode). In this case <limit> should be "0".