3
0
mirror of https://github.com/ergochat/ergo.git synced 2024-12-23 11:12:44 +01:00
ergo/irc/channel.go
2017-11-22 05:09:38 -05:00

795 lines
23 KiB
Go

// Copyright (c) 2012-2014 Jeremy Latt
// Copyright (c) 2014-2015 Edmund Huber
// Copyright (c) 2016-2017 Daniel Oaks <daniel@danieloaks.net>
// released under the MIT license
package irc
import (
"errors"
"fmt"
"strconv"
"time"
"sync"
"github.com/goshuirc/irc-go/ircmsg"
"github.com/oragono/oragono/irc/caps"
)
var (
ChannelAlreadyRegistered = errors.New("Channel is already registered")
)
// Channel represents a channel that clients can join.
type Channel struct {
flags ModeSet
lists map[Mode]*UserMaskSet
key string
members MemberSet
membersCache []*Client // allow iteration over channel members without holding the lock
membersCacheMutex sync.Mutex // tier 2; see `regenerateMembersCache`
name string
nameCasefolded string
server *Server
createdTime time.Time
registeredFounder string
registeredTime time.Time
stateMutex sync.RWMutex // tier 1
topic string
topicSetBy string
topicSetTime time.Time
userLimit uint64
}
// NewChannel creates a new channel from a `Server` and a `name`
// string, which must be unique on the server.
func NewChannel(s *Server, name string, addDefaultModes bool, regInfo *RegisteredChannel) *Channel {
casefoldedName, err := CasefoldChannel(name)
if err != nil {
s.logger.Error("internal", fmt.Sprintf("Bad channel name %s: %v", name, err))
return nil
}
channel := &Channel{
createdTime: time.Now(), // may be overwritten by applyRegInfo
flags: make(ModeSet),
lists: map[Mode]*UserMaskSet{
BanMask: NewUserMaskSet(),
ExceptMask: NewUserMaskSet(),
InviteMask: NewUserMaskSet(),
},
members: make(MemberSet),
name: name,
nameCasefolded: casefoldedName,
server: s,
}
if addDefaultModes {
for _, mode := range s.DefaultChannelModes() {
channel.flags[mode] = true
}
}
if regInfo != nil {
channel.applyRegInfo(regInfo)
}
return channel
}
// read in channel state that was persisted in the DB
func (channel *Channel) applyRegInfo(chanReg *RegisteredChannel) {
channel.registeredFounder = chanReg.Founder
channel.registeredTime = chanReg.RegisteredAt
channel.topic = chanReg.Topic
channel.topicSetBy = chanReg.TopicSetBy
channel.topicSetTime = chanReg.TopicSetTime
channel.name = chanReg.Name
channel.createdTime = chanReg.RegisteredAt
for _, mask := range chanReg.Banlist {
channel.lists[BanMask].Add(mask)
}
for _, mask := range chanReg.Exceptlist {
channel.lists[ExceptMask].Add(mask)
}
for _, mask := range chanReg.Invitelist {
channel.lists[InviteMask].Add(mask)
}
}
// obtain a consistent snapshot of the channel state that can be persisted to the DB
func (channel *Channel) ExportRegistration(includeLists bool) (info RegisteredChannel) {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
info.Name = channel.name
info.Topic = channel.topic
info.TopicSetBy = channel.topicSetBy
info.TopicSetTime = channel.topicSetTime
info.Founder = channel.registeredFounder
info.RegisteredAt = channel.registeredTime
if includeLists {
for mask := range channel.lists[BanMask].masks {
info.Banlist = append(info.Banlist, mask)
}
for mask := range channel.lists[ExceptMask].masks {
info.Exceptlist = append(info.Exceptlist, mask)
}
for mask := range channel.lists[InviteMask].masks {
info.Invitelist = append(info.Invitelist, mask)
}
}
return
}
// SetRegistered registers the channel, returning an error if it was already registered.
func (channel *Channel) SetRegistered(founder string) error {
channel.stateMutex.Lock()
defer channel.stateMutex.Unlock()
if channel.registeredFounder != "" {
return ChannelAlreadyRegistered
}
channel.registeredFounder = founder
channel.registeredTime = time.Now()
return nil
}
// IsRegistered returns whether the channel is registered.
func (channel *Channel) IsRegistered() bool {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
return channel.registeredFounder != ""
}
func (channel *Channel) regenerateMembersCache() {
// this is eventually consistent even without holding stateMutex.Lock()
// throughout the update; all updates to `members` while holding Lock()
// have a serial order, so the call to `regenerateMembersCache` that
// happens-after the last one will see *all* the updates. then,
// `membersCacheMutex` ensures that this final read is correctly paired
// with the final write to `membersCache`.
channel.membersCacheMutex.Lock()
defer channel.membersCacheMutex.Unlock()
channel.stateMutex.RLock()
result := make([]*Client, len(channel.members))
i := 0
for client := range channel.members {
result[i] = client
i++
}
channel.stateMutex.RUnlock()
channel.stateMutex.Lock()
channel.membersCache = result
channel.stateMutex.Unlock()
return
}
// Names sends the list of users joined to the channel to the given client.
func (channel *Channel) Names(client *Client) {
currentNicks := channel.nicks(client)
// assemble and send replies
maxNamLen := 480 - len(client.server.name) - len(client.nick)
var buffer string
for _, nick := range currentNicks {
if buffer == "" {
buffer += nick
continue
}
if len(buffer)+1+len(nick) > maxNamLen {
client.Send(nil, client.server.name, RPL_NAMREPLY, client.nick, "=", channel.name, buffer)
buffer = nick
continue
}
buffer += " "
buffer += nick
}
client.Send(nil, client.server.name, RPL_NAMREPLY, client.nick, "=", channel.name, buffer)
client.Send(nil, client.server.name, RPL_ENDOFNAMES, client.nick, channel.name, "End of NAMES list")
}
// ClientIsAtLeast returns whether the client has at least the given channel privilege.
func (channel *Channel) ClientIsAtLeast(client *Client, permission Mode) bool {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
// get voice, since it's not a part of ChannelPrivModes
if channel.members.HasMode(client, permission) {
return true
}
// check regular modes
for _, mode := range ChannelPrivModes {
if channel.members.HasMode(client, mode) {
return true
}
if mode == permission {
break
}
}
return false
}
// Prefixes returns a list of prefixes for the given set of channel modes.
func (modes ModeSet) Prefixes(isMultiPrefix bool) string {
var prefixes string
// add prefixes in order from highest to lowest privs
for _, mode := range ChannelPrivModes {
if modes[mode] {
prefixes += ChannelModePrefixes[mode]
}
}
if modes[Voice] {
prefixes += ChannelModePrefixes[Voice]
}
if !isMultiPrefix && len(prefixes) > 1 {
prefixes = string(prefixes[0])
}
return prefixes
}
func (channel *Channel) ClientPrefixes(client *Client, isMultiPrefix bool) string {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
modes, present := channel.members[client]
if !present {
return ""
} else {
return modes.Prefixes(isMultiPrefix)
}
}
func (channel *Channel) ClientHasPrivsOver(client *Client, target *Client) bool {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
clientModes := channel.members[client]
targetModes := channel.members[target]
result := false
for _, mode := range ChannelPrivModes {
if clientModes[mode] {
result = true
// admins cannot kick other admins
if mode == ChannelAdmin && targetModes[ChannelAdmin] {
result = false
}
break
} else if channel.members[target][mode] {
break
}
}
return result
}
func (channel *Channel) nicks(target *Client) []string {
isMultiPrefix := (target != nil) && target.capabilities.Has(caps.MultiPrefix)
isUserhostInNames := (target != nil) && target.capabilities.Has(caps.UserhostInNames)
// slightly cumbersome: get the mutex and copy both the client pointers and
// the mode prefixes
channel.stateMutex.RLock()
length := len(channel.members)
clients := make([]*Client, length)
result := make([]string, length)
i := 0
for client, modes := range channel.members {
clients[i] = client
result[i] = modes.Prefixes(isMultiPrefix)
i++
}
channel.stateMutex.RUnlock()
i = 0
for i < length {
if isUserhostInNames {
result[i] += clients[i].NickMaskString()
} else {
result[i] += clients[i].Nick()
}
i++
}
return result
}
func (channel *Channel) hasClient(client *Client) bool {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
_, present := channel.members[client]
return present
}
// <mode> <mode params>
func (channel *Channel) modeStrings(client *Client) (result []string) {
isMember := client.HasMode(Operator) || channel.hasClient(client)
showKey := isMember && (channel.key != "")
showUserLimit := channel.userLimit > 0
modes := "+"
// flags with args
if showKey {
modes += Key.String()
}
if showUserLimit {
modes += UserLimit.String()
}
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
// flags
for mode := range channel.flags {
modes += mode.String()
}
result = []string{modes}
// args for flags with args: The order must match above to keep
// positional arguments in place.
if showKey {
result = append(result, channel.key)
}
if showUserLimit {
result = append(result, strconv.FormatUint(channel.userLimit, 10))
}
return
}
// IsFull returns true if this channel is at its' members limit.
func (channel *Channel) IsFull() bool {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
return (channel.userLimit > 0) && (uint64(len(channel.members)) >= channel.userLimit)
}
// CheckKey returns true if the key is not set or matches the given key.
func (channel *Channel) CheckKey(key string) bool {
return (channel.key == "") || (channel.key == key)
}
func (channel *Channel) IsEmpty() bool {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
return len(channel.members) == 0
}
// Join joins the given client to this channel (if they can be joined).
//TODO(dan): /SAJOIN and maybe a ForceJoin function?
func (channel *Channel) Join(client *Client, key string) {
if channel.hasClient(client) {
// already joined, no message needs to be sent
return
}
if channel.IsFull() {
client.Send(nil, client.server.name, ERR_CHANNELISFULL, channel.name, "Cannot join channel (+l)")
return
}
if !channel.CheckKey(key) {
client.Send(nil, client.server.name, ERR_BADCHANNELKEY, channel.name, "Cannot join channel (+k)")
return
}
isInvited := channel.lists[InviteMask].Match(client.nickMaskCasefolded)
if channel.flags[InviteOnly] && !isInvited {
client.Send(nil, client.server.name, ERR_INVITEONLYCHAN, channel.name, "Cannot join channel (+i)")
return
}
if channel.lists[BanMask].Match(client.nickMaskCasefolded) &&
!isInvited &&
!channel.lists[ExceptMask].Match(client.nickMaskCasefolded) {
client.Send(nil, client.server.name, ERR_BANNEDFROMCHAN, channel.name, "Cannot join channel (+b)")
return
}
client.server.logger.Debug("join", fmt.Sprintf("%s joined channel %s", client.nick, channel.name))
for _, member := range channel.Members() {
if member.capabilities.Has(caps.ExtendedJoin) {
member.Send(nil, client.nickMaskString, "JOIN", channel.name, client.account.Name, client.realname)
} else {
member.Send(nil, client.nickMaskString, "JOIN", channel.name)
}
}
channel.stateMutex.Lock()
channel.members.Add(client)
firstJoin := len(channel.members) == 1
channel.stateMutex.Unlock()
channel.regenerateMembersCache()
client.addChannel(channel)
// give channel mode if necessary
newChannel := firstJoin && !channel.IsRegistered()
var givenMode *Mode
if client.AccountName() == channel.registeredFounder {
givenMode = &ChannelFounder
} else if newChannel {
givenMode = &ChannelOperator
}
if givenMode != nil {
channel.stateMutex.Lock()
channel.members[client][*givenMode] = true
channel.stateMutex.Unlock()
}
if client.capabilities.Has(caps.ExtendedJoin) {
client.Send(nil, client.nickMaskString, "JOIN", channel.name, client.account.Name, client.realname)
} else {
client.Send(nil, client.nickMaskString, "JOIN", channel.name)
}
// don't send topic when it's an entirely new channel
if !newChannel {
channel.SendTopic(client)
}
channel.Names(client)
if givenMode != nil {
for _, member := range channel.Members() {
member.Send(nil, client.server.name, "MODE", channel.name, fmt.Sprintf("+%v", *givenMode), client.nick)
}
}
}
// Part parts the given client from this channel, with the given message.
func (channel *Channel) Part(client *Client, message string) {
if !channel.hasClient(client) {
client.Send(nil, client.server.name, ERR_NOTONCHANNEL, channel.name, "You're not on that channel")
return
}
for _, member := range channel.Members() {
member.Send(nil, client.nickMaskString, "PART", channel.name, message)
}
channel.Quit(client)
client.server.logger.Debug("part", fmt.Sprintf("%s left channel %s", client.nick, channel.name))
}
// SendTopic sends the channel topic to the given client.
func (channel *Channel) SendTopic(client *Client) {
if !channel.hasClient(client) {
client.Send(nil, client.server.name, ERR_NOTONCHANNEL, client.nick, channel.name, "You're not on that channel")
return
}
channel.stateMutex.RLock()
name := channel.name
topic := channel.topic
topicSetBy := channel.topicSetBy
topicSetTime := channel.topicSetTime
channel.stateMutex.RUnlock()
if topic == "" {
client.Send(nil, client.server.name, RPL_NOTOPIC, client.nick, name, "No topic is set")
return
}
client.Send(nil, client.server.name, RPL_TOPIC, client.nick, name, topic)
client.Send(nil, client.server.name, RPL_TOPICTIME, client.nick, name, topicSetBy, strconv.FormatInt(topicSetTime.Unix(), 10))
}
// SetTopic sets the topic of this channel, if the client is allowed to do so.
func (channel *Channel) SetTopic(client *Client, topic string) {
if !(client.flags[Operator] || channel.hasClient(client)) {
client.Send(nil, client.server.name, ERR_NOTONCHANNEL, channel.name, "You're not on that channel")
return
}
if channel.HasMode(OpOnlyTopic) && !channel.ClientIsAtLeast(client, ChannelOperator) {
client.Send(nil, client.server.name, ERR_CHANOPRIVSNEEDED, channel.name, "You're not a channel operator")
return
}
if len(topic) > client.server.limits.TopicLen {
topic = topic[:client.server.limits.TopicLen]
}
channel.stateMutex.Lock()
channel.topic = topic
channel.topicSetBy = client.nickMaskString
channel.topicSetTime = time.Now()
channel.stateMutex.Unlock()
for _, member := range channel.Members() {
member.Send(nil, client.nickMaskString, "TOPIC", channel.name, topic)
}
go channel.server.channelRegistry.StoreChannel(channel, false)
}
// CanSpeak returns true if the client can speak on this channel.
func (channel *Channel) CanSpeak(client *Client) bool {
channel.stateMutex.RLock()
defer channel.stateMutex.RUnlock()
_, hasClient := channel.members[client]
if channel.flags[NoOutside] && !hasClient {
return false
}
if channel.flags[Moderated] && !channel.ClientIsAtLeast(client, Voice) {
return false
}
if channel.flags[RegisteredOnly] && client.account == &NoAccount {
return false
}
return true
}
// TagMsg sends a tag message to everyone in this channel who can accept them.
func (channel *Channel) TagMsg(msgid string, minPrefix *Mode, clientOnlyTags *map[string]ircmsg.TagValue, client *Client) {
channel.sendMessage(msgid, "TAGMSG", []caps.Capability{caps.MessageTags}, minPrefix, clientOnlyTags, client, nil)
}
// sendMessage sends a given message to everyone on this channel.
func (channel *Channel) sendMessage(msgid, cmd string, requiredCaps []caps.Capability, minPrefix *Mode, clientOnlyTags *map[string]ircmsg.TagValue, client *Client, message *string) {
if !channel.CanSpeak(client) {
client.Send(nil, client.server.name, ERR_CANNOTSENDTOCHAN, channel.name, "Cannot send to channel")
return
}
// for STATUSMSG
var minPrefixMode Mode
if minPrefix != nil {
minPrefixMode = *minPrefix
}
for _, member := range channel.Members() {
if minPrefix != nil && !channel.ClientIsAtLeast(member, minPrefixMode) {
// STATUSMSG
continue
}
if member == client && !client.capabilities.Has(caps.EchoMessage) {
continue
}
canReceive := true
for _, capName := range requiredCaps {
if !member.capabilities.Has(capName) {
canReceive = false
}
}
if !canReceive {
continue
}
var messageTagsToUse *map[string]ircmsg.TagValue
if member.capabilities.Has(caps.MessageTags) {
messageTagsToUse = clientOnlyTags
}
if message == nil {
member.SendFromClient(msgid, client, messageTagsToUse, cmd, channel.name)
} else {
member.SendFromClient(msgid, client, messageTagsToUse, cmd, channel.name, *message)
}
}
}
// SplitPrivMsg sends a private message to everyone in this channel.
func (channel *Channel) SplitPrivMsg(msgid string, minPrefix *Mode, clientOnlyTags *map[string]ircmsg.TagValue, client *Client, message SplitMessage) {
channel.sendSplitMessage(msgid, "PRIVMSG", minPrefix, clientOnlyTags, client, &message)
}
// SplitNotice sends a private message to everyone in this channel.
func (channel *Channel) SplitNotice(msgid string, minPrefix *Mode, clientOnlyTags *map[string]ircmsg.TagValue, client *Client, message SplitMessage) {
channel.sendSplitMessage(msgid, "NOTICE", minPrefix, clientOnlyTags, client, &message)
}
func (channel *Channel) sendSplitMessage(msgid, cmd string, minPrefix *Mode, clientOnlyTags *map[string]ircmsg.TagValue, client *Client, message *SplitMessage) {
if !channel.CanSpeak(client) {
client.Send(nil, client.server.name, ERR_CANNOTSENDTOCHAN, channel.name, "Cannot send to channel")
return
}
// for STATUSMSG
var minPrefixMode Mode
if minPrefix != nil {
minPrefixMode = *minPrefix
}
for _, member := range channel.Members() {
if minPrefix != nil && !channel.ClientIsAtLeast(member, minPrefixMode) {
// STATUSMSG
continue
}
if member == client && !client.capabilities.Has(caps.EchoMessage) {
continue
}
var tagsToUse *map[string]ircmsg.TagValue
if member.capabilities.Has(caps.MessageTags) {
tagsToUse = clientOnlyTags
}
if message == nil {
member.SendFromClient(msgid, client, tagsToUse, cmd, channel.name)
} else {
member.SendSplitMsgFromClient(msgid, client, tagsToUse, cmd, channel.name, *message)
}
}
}
func (channel *Channel) applyModeMemberNoMutex(client *Client, mode Mode,
op ModeOp, nick string) *ModeChange {
if nick == "" {
//TODO(dan): shouldn't this be handled before it reaches this function?
client.Send(nil, client.server.name, ERR_NEEDMOREPARAMS, "MODE", "Not enough parameters")
return nil
}
casefoldedName, err := CasefoldName(nick)
target := channel.server.clients.Get(casefoldedName)
if err != nil || target == nil {
client.Send(nil, client.server.name, ERR_NOSUCHNICK, client.nick, nick, "No such nick")
return nil
}
channel.stateMutex.Lock()
modeset, exists := channel.members[target]
var already bool
if exists {
enable := op == Add
already = modeset[mode] == enable
modeset[mode] = enable
}
channel.stateMutex.Unlock()
if !exists {
client.Send(nil, client.server.name, ERR_USERNOTINCHANNEL, client.nick, channel.name, "They aren't on that channel")
return nil
} else if already {
return nil
} else {
return &ModeChange{
op: op,
mode: mode,
arg: nick,
}
}
}
// ShowMaskList shows the given list to the client.
func (channel *Channel) ShowMaskList(client *Client, mode Mode) {
// choose appropriate modes
var rpllist, rplendoflist string
if mode == BanMask {
rpllist = RPL_BANLIST
rplendoflist = RPL_ENDOFBANLIST
} else if mode == ExceptMask {
rpllist = RPL_EXCEPTLIST
rplendoflist = RPL_ENDOFEXCEPTLIST
} else if mode == InviteMask {
rpllist = RPL_INVITELIST
rplendoflist = RPL_ENDOFINVITELIST
}
nick := client.Nick()
channel.stateMutex.RLock()
// XXX don't acquire any new locks in this section, besides Socket.Write
for mask := range channel.lists[mode].masks {
client.Send(nil, client.server.name, rpllist, nick, channel.name, mask)
}
channel.stateMutex.RUnlock()
client.Send(nil, client.server.name, rplendoflist, nick, channel.name, "End of list")
}
func (channel *Channel) applyModeMask(client *Client, mode Mode, op ModeOp, mask string) bool {
list := channel.lists[mode]
if list == nil {
// This should never happen, but better safe than panicky.
return false
}
if (op == List) || (mask == "") {
channel.ShowMaskList(client, mode)
return false
}
if !channel.ClientIsAtLeast(client, ChannelOperator) {
client.Send(nil, client.server.name, ERR_CHANOPRIVSNEEDED, channel.name, "You're not a channel operator")
return false
}
if op == Add {
return list.Add(mask)
}
if op == Remove {
return list.Remove(mask)
}
return false
}
// Quit removes the given client from the channel
func (channel *Channel) Quit(client *Client) {
channel.stateMutex.Lock()
channel.members.Remove(client)
channel.stateMutex.Unlock()
channel.regenerateMembersCache()
client.removeChannel(channel)
}
func (channel *Channel) Kick(client *Client, target *Client, comment string) {
if !(client.flags[Operator] || channel.hasClient(client)) {
client.Send(nil, client.server.name, ERR_NOTONCHANNEL, channel.name, "You're not on that channel")
return
}
if !channel.ClientIsAtLeast(client, ChannelOperator) {
client.Send(nil, client.server.name, ERR_CANNOTSENDTOCHAN, channel.name, "Cannot send to channel")
return
}
if !channel.hasClient(target) {
client.Send(nil, client.server.name, ERR_USERNOTINCHANNEL, client.nick, channel.name, "They aren't on that channel")
return
}
if !channel.ClientHasPrivsOver(client, target) {
client.Send(nil, client.server.name, ERR_CHANOPRIVSNEEDED, channel.name, "You're not a channel operator")
return
}
kicklimit := client.server.Limits().KickLen
if len(comment) > kicklimit {
comment = comment[:kicklimit]
}
clientMask := client.NickMaskString()
targetNick := target.Nick()
for _, member := range channel.Members() {
member.Send(nil, clientMask, "KICK", channel.name, targetNick, comment)
}
channel.Quit(target)
}
// Invite invites the given client to the channel, if the inviter can do so.
func (channel *Channel) Invite(invitee *Client, inviter *Client) {
if channel.flags[InviteOnly] && !channel.ClientIsAtLeast(inviter, ChannelOperator) {
inviter.Send(nil, inviter.server.name, ERR_CHANOPRIVSNEEDED, channel.name, "You're not a channel operator")
return
}
if !channel.hasClient(inviter) {
inviter.Send(nil, inviter.server.name, ERR_NOTONCHANNEL, channel.name, "You're not on that channel")
return
}
//TODO(dan): handle this more nicely, keep a list of last X invited channels on invitee rather than explicitly modifying the invite list?
if channel.flags[InviteOnly] {
nmc := invitee.NickCasefolded()
channel.stateMutex.Lock()
channel.lists[InviteMask].Add(nmc)
channel.stateMutex.Unlock()
}
for _, member := range channel.Members() {
if member.capabilities.Has(caps.InviteNotify) && member != inviter && member != invitee && channel.ClientIsAtLeast(member, Halfop) {
member.Send(nil, inviter.NickMaskString(), "INVITE", invitee.Nick(), channel.name)
}
}
//TODO(dan): should inviter.server.name here be inviter.nickMaskString ?
inviter.Send(nil, inviter.server.name, RPL_INVITING, invitee.nick, channel.name)
invitee.Send(nil, inviter.nickMaskString, "INVITE", invitee.nick, channel.name)
if invitee.flags[Away] {
inviter.Send(nil, inviter.server.name, RPL_AWAY, invitee.nick, invitee.awayMessage)
}
}