doc/oper-guide/cmodes.rst

   1 Channel modes
   2 =============
   3
   4 Channel modes are determined by the various plugins loaded by the
   5 server. The following consists only of a base list of common modes:
   6 your server may have more plugins available, which you can see with
   7 the following server command, depending on your IRC client::
   8
   9   /QUOTE HELP CMODE
  10
  11 or::
  12
  13   /RAW HELP CMODE
  14
  15 ``+b``, channel ban
  16 -------------------
  17
  18 Bans take one parameter which can take several forms. The most common
  19 form is ``+b nick!user@host``. The wildcards ``*`` and ``?`` are
  20 allowed, matching zero-or-more, and exactly-one characters
  21 respectively. The masks will be trimmed to fit the maximum allowable
  22 length for the relevant element.  Bans are also checked against the IP
  23 address, even if it resolved or is spoofed. CIDR is supported, like
  24 ``*!*@10.0.0.0/8``. This is most useful with IPv6. Bans are not
  25 checked against the real hostname behind any kind of spoof, except if
  26 host mangling is in use (e.g.  ``extensions/ip_cloaking.so``): if the
  27 user's host is mangled, their real hostname is checked additionally,
  28 and if a user has no spoof but could enable mangling, the mangled form
  29 of their hostname is checked additionally. Hence, it is not possible
  30 to evade bans by toggling host mangling.
  31
  32 The second form (extban) is ``+b $type`` or ``+b $type:data``. type is
  33 a single character (case insensitive) indicating the type of match,
  34 optionally preceded by a tilde (``~``) to negate the comparison. data
  35 depends on type.  Each type is loaded as a module. The available types
  36 (if any) are listed in the ``EXTBAN`` token of the 005
  37 (``RPL_ISUPPORT``) numeric. See ``doc/extban.txt`` in the source
  38 distribution or ``HELP EXTBAN`` for more information.
  39
  40 If no parameter is given, the list of bans is returned. All users can
  41 use this form. The plus sign should also be omitted.
  42
  43 Matching users will not be allowed to join the channel or knock on it.
  44 If they are already on the channel, they may not send to it or change
  45 their nick.
  46
  47 ``+c``, colour filter
  48 ---------------------
  49
  50 This cmode activates the colour filter for the channel. This filters out
  51 bold, underline, reverse video, beeps, mIRC colour codes, and ANSI
  52 escapes. Note that escape sequences will usually leave cruft sent to the
  53 channel, just without the escape characters themselves.
  54
  55 ``+e``, ban exemption
  56 ---------------------
  57
  58 This mode takes one parameter of the same form as bans, which overrides
  59 ``+b`` and ``+q`` bans for all clients it matches.
  60
  61 This can be useful if it is necessary to ban an entire ISP due to
  62 persistent abuse, but some users from that ISP should still be allowed
  63 in. For example::
  64
  65   /mode #channel +be *!*@*.example.com *!*someuser@host3.example.com
  66
  67 Only channel operators can see ``+e`` changes or request the list.
  68
  69 ``+f``, channel forwarding
  70 --------------------------
  71
  72 This mode takes one parameter, the name of a channel (``+f
  73 #channel``). If the channel also has the ``+i`` cmode set, and
  74 somebody attempts to join without either being expliticly invited, or
  75 having an invex (``+I``), then they will instead join the channel
  76 named in the mode parameter. The client will also be sent a 470
  77 numeric giving the original and target channels.
  78
  79 Users are similarly forwarded if the ``+j`` cmode is set and their attempt
  80 to join is throttled, if ``+l`` is set and there are already too many users
  81 in the channel or if ``+r`` is set and they are not identified.
  82
  83 Forwards may only be set to ``+F`` channels, or to channels the setter has
  84 ops in.
  85
  86 Without parameter (``/mode #channel f`` or ``/mode #channel +f``) the forward
  87 channel is returned. This form also works off channel.
  88
  89 ``+F``, allow anybody to forward to this
  90 ----------------------------------------
  91
  92 When this mode is set, anybody may set a forward from a channel they
  93 have ops in to this channel. Otherwise they have to have ops in this
  94 channel.
  95
  96 ``+g``, allow anybody to invite
  97 -------------------------------
  98
  99 When this mode is set, anybody may use the ``INVITE`` command on the channel
 100 in question. When it is unset, only channel operators may use the ``INVITE``
 101 command.
 102
 103 When this mode is set together with ``+i``, ``+j``, ``+l`` or ``+r``, all channel
 104 members can influence who can join.
 105
 106 ``+i``, invite only
 107 -------------------
 108
 109 When this cmode is set, no client can join the channel unless they have
 110 an invex (``+I``) or are invited with the ``INVITE`` command.
 111
 112 ``+I``, invite exception (invex)
 113 --------------------------------
 114
 115 This mode takes one parameter of the same form as bans. Matching clients
 116 do not need to be invited to join the channel when it is invite-only
 117 (``+i``). Unlike the ``INVITE`` command, this does not override ``+j``, ``+l`` and ``+r``.
 118
 119 Only channel operators can see ``+I`` changes or request the list.
 120
 121 ``+j``, join throttling
 122 -----------------------
 123
 124 This mode takes one parameter of the form n:t, where n and t are
 125 positive integers. Only n users may join in each period of t seconds.
 126
 127 Invited users can join regardless of ``+j``, but are counted as normal.
 128
 129 Due to propagation delays between servers, more users may be able to
 130 join (by racing for the last slot on each server).
 131
 132 ``+k``, key (channel password)
 133 ------------------------------
 134
 135 Taking one parameter, when set, this mode requires a user to supply the
 136 key in order to join the channel: ``/JOIN #channel key``.
 137
 138 ``+l``, channel member limit
 139 ----------------------------
 140
 141 Takes one numeric parameter, the number of users which are allowed to be
 142 in the channel before further joins are blocked. Invited users may join
 143 regardless.
 144
 145 Due to propagation delays between servers, more users may be able to
 146 join (by racing for the last slot on each server).
 147
 148 ``+L``, large ban list
 149 ----------------------
 150
 151 Channels with this mode will be allowed larger banlists (by default, 500
 152 instead of 50 entries for ``+b``, ``+q``, ``+e`` and ``+I`` together). Only network
 153 operators with resv privilege may set this mode.
 154
 155 ``+m``, moderated
 156 -----------------
 157
 158 When a channel is set ``+m``, only users with ``+o`` or ``+v`` on the channel can
 159 send to it.
 160
 161 Users can still knock on the channel or change their nick.
 162
 163 ``+n``, no external messages
 164 ----------------------------
 165
 166 When set, this mode prevents users from sending to the channel without
 167 being in it themselves. This is recommended.
 168
 169 ``+o``, channel operator
 170 ------------------------
 171
 172 This mode takes one parameter, a nick, and grants or removes channel
 173 operator privilege to that user. Channel operators have full control
 174 over the channel, having the ability to set all channel modes except ``+L``
 175 and ``+P``, and kick users. Like voiced users, channel operators can always
 176 send to the channel, overriding ``+b``, ``+m`` and ``+q`` modes and the per-channel
 177 flood limit. In most clients channel operators are marked with an '@'
 178 sign.
 179
 180 The privilege is lost if the user leaves the channel or server in any
 181 way.
 182
 183 Most networks will run channel registration services (e.g. ChanServ)
 184 which ensure the founder (and users designated by the founder) can
 185 always gain channel operator privileges and provide some features to
 186 manage the channel.
 187
 188 ``+p``, paranoid channel
 189 ------------------------
 190
 191 When set, the ``KNOCK`` command cannot be used on the channel to request an
 192 invite, and users will not be shown the channel in ``WHOIS`` replies unless
 193 they are on it. Unlike in traditional IRC, ``+p`` and ``+s`` can be set
 194 together.
 195
 196 ``+P``, permanent channel
 197 -------------------------
 198
 199 Channels with this mode (which is accessible only to network operators
 200 with resv privilege) set will not be destroyed when the last user
 201 leaves.
 202
 203 This makes it less likely modes, bans and the topic will be lost and
 204 makes it harder to abuse network splits, but also causes more unwanted
 205 restoring of old modes, bans and topics after long splits.
 206
 207 ``+q``, quiet
 208 -------------
 209
 210 This mode behaves exactly like ``+b`` (ban), except that the user may still
 211 join the channel. The net effect is that they cannot knock on the
 212 channel, send to the channel or change their nick while on channel.
 213
 214 ``+Q``, block forwarded users
 215 -----------------------------
 216
 217 Channels with this mode set are not valid targets for forwarding. Any
 218 attempt to forward to this channel will be ignored, and the user will be
 219 handled as if the attempt was never made (by sending them the relevant
 220 error message).
 221
 222 This does not affect the ability to set ``+f``.
 223
 224 ``+r``, block unidentified
 225 --------------------------
 226
 227 When set, this mode prevents unidentified users from joining. Invited
 228 users can still join.
 229
 230 ``+s``, secret channel
 231 ----------------------
 232
 233 When set, this mode prevents the channel from appearing in the output of
 234 the ``LIST``, ``WHO`` and ``WHOIS`` command by users who are not on it. Also, the
 235 server will refuse to answer ``WHO``, ``NAMES``, ``TOPIC`` and ``LIST`` queries from
 236 users not on the channel.
 237
 238 ``+t``, topic limit
 239 -------------------
 240
 241 When set, this mode prevents users who are not channel operators from
 242 changing the topic.
 243
 244 ``+v``, voice
 245 -------------
 246
 247 This mode takes one parameter, a nick, and grants or removes voice
 248 privilege to that user. Voiced users can always send to the channel,
 249 overriding ``+b``, ``+m`` and ``+q`` modes and the per-channel flood limit. In most
 250 clients voiced users are marked with a plus sign.
 251
 252 The privilege is lost if the user leaves the channel or server in any
 253 way.
 254
 255 ``+z``, reduced moderation
 256 --------------------------
 257
 258 When ``+z`` is set, the effects of ``+m``, ``+b`` and ``+q`` are relaxed. For each
 259 message, if that message would normally be blocked by one of these
 260 modes, it is instead sent to all channel operators. This is intended for
 261 use in moderated debates.
 262
 263 Note that ``+n`` is unaffected by this. To silence a given user completely,
 264 remove them from the channel.