Merge pull request #274 from slingamn/chanunreg.1

add CHANSERV UNREGISTER

irc/channel.go

@@ -157,6 +157,17 @@ func (channel *Channel) SetRegistered(founder string) error {
 	return nil
 }
 
+// SetUnregistered deletes the channel's registration information.
+func (channel *Channel) SetUnregistered() {
+	channel.stateMutex.Lock()
+	defer channel.stateMutex.Unlock()
+
+	channel.registeredFounder = ""
+	var zeroTime time.Time
+	channel.registeredTime = zeroTime
+	channel.accountToUMode = make(map[string]modes.Mode)
+}
+
 // IsRegistered returns whether the channel is registered.
 func (channel *Channel) IsRegistered() bool {
 	channel.stateMutex.RLock()

irc/channelreg.go

@@ -201,6 +201,20 @@ func (reg *ChannelRegistry) LoadChannel(nameCasefolded string) (info *Registered
 	return info
 }
 
+func (reg *ChannelRegistry) Delete(casefoldedName string, info RegisteredChannel) {
+	if !reg.server.ChannelRegistrationEnabled() {
+		return
+	}
+
+	reg.Lock()
+	defer reg.Unlock()
+
+	reg.server.store.Update(func(tx *buntdb.Tx) error {
+		reg.deleteChannel(tx, casefoldedName, info)
+		return nil
+	})
+}
+
 // Rename handles the persistence part of a channel rename: the channel is
 // persisted under its new name, and the old name is cleaned up if necessary.
 func (reg *ChannelRegistry) Rename(channel *Channel, casefoldedOldName string) {

irc/chanserv.go

@@ -4,8 +4,11 @@
 package irc
 
 import (
+	"bytes"
 	"fmt"
+	"hash/crc32"
 	"sort"
+	"strconv"
 	"strings"
 
 	"github.com/goshuirc/irc-go/ircfmt"
@@ -22,6 +25,10 @@ To see in-depth help for a specific ChanServ command, try:
 Here are the commands you can use:
 %s`
 
+func chanregEnabled(server *Server) bool {
+	return server.ChannelRegistrationEnabled()
+}
+
 var (
 	chanservCommands = map[string]*serviceCommand{
 		"op": {
@@ -32,6 +39,7 @@ OP makes the given nickname, or yourself, a channel admin. You can only use
 this command if you're the founder of the channel.`,
 			helpShort:    `$bOP$b makes the given user (or yourself) a channel admin.`,
 			authRequired: true,
+			enabled:      chanregEnabled,
 		},
 		"register": {
 			handler: csRegisterHandler,
@@ -42,6 +50,17 @@ given admin privs on it. Modes set on the channel and the topic will also be
 remembered.`,
 			helpShort:    `$bREGISTER$b lets you own a given channel.`,
 			authRequired: true,
+			enabled:      chanregEnabled,
+		},
+		"unregister": {
+			handler: csUnregisterHandler,
+			help: `Syntax: $bUNREGISTER #channel [code]$b
+
+UNREGISTER deletes a channel registration, allowing someone else to claim it.
+To prevent accidental unregistrations, a verification code is required;
+invoking the command without a code will display the necessary code.`,
+			helpShort: `$bUNREGISTER$b deletes a channel registration.`,
+			enabled:   chanregEnabled,
 		},
 		"amode": {
 			handler: csAmodeHandler,
@@ -53,6 +72,7 @@ account the +o operator mode every time they join #channel. To list current
 accounts and modes, use $bAMODE #channel$b. Note that users are always
 referenced by their registered account names, not their nicknames.`,
 			helpShort: `$bAMODE$b modifies persistent mode settings for channel members.`,
+			enabled:   chanregEnabled,
 		},
 	}
 )
@@ -197,11 +217,6 @@ func csOpHandler(server *Server, client *Client, command, params string, rb *Res
 }
 
 func csRegisterHandler(server *Server, client *Client, command, params string, rb *ResponseBuffer) {
-	if !server.channelRegistrationEnabled {
-		csNotice(rb, client.t("Channel registration is not enabled"))
-		return
-	}
-
 	channelName := strings.TrimSpace(params)
 	if channelName == "" {
 		csNotice(rb, ircfmt.Unescape(client.t("Syntax: $bREGISTER #channel$b")))
@@ -246,3 +261,45 @@ func csRegisterHandler(server *Server, client *Client, command, params string, r
 		}
 	}
 }
+
+func csUnregisterHandler(server *Server, client *Client, command, params string, rb *ResponseBuffer) {
+	channelName, verificationCode := utils.ExtractParam(params)
+	channelKey, err := CasefoldChannel(channelName)
+	if channelKey == "" || err != nil {
+		csNotice(rb, client.t("Channel name is not valid"))
+		return
+	}
+
+	channel := server.channels.Get(channelKey)
+	if channel == nil {
+		csNotice(rb, client.t("No such channel"))
+		return
+	}
+
+	hasPrivs := client.HasRoleCapabs("chanreg")
+	if !hasPrivs {
+		founder := channel.Founder()
+		hasPrivs = founder != "" && founder == client.Account()
+	}
+	if !hasPrivs {
+		csNotice(rb, client.t("Insufficient privileges"))
+		return
+	}
+
+	info := channel.ExportRegistration(0)
+	// verification code is the crc32 of the name, plus the registration time
+	var codeInput bytes.Buffer
+	codeInput.WriteString(info.Name)
+	codeInput.WriteString(strconv.FormatInt(info.RegisteredAt.Unix(), 16))
+	expectedCode := int(crc32.ChecksumIEEE(codeInput.Bytes()))
+	receivedCode, err := strconv.Atoi(verificationCode)
+	if err != nil || expectedCode != receivedCode {
+		csNotice(rb, client.t("$bWarning:$b Unregistering this channel will remove all stored channel attributes."))
+		csNotice(rb, fmt.Sprintf(client.t("To confirm channel unregistration, type: /CS UNREGISTER %s %d"), channelKey, expectedCode))
+		return
+	}
+
+	channel.SetUnregistered()
+	go server.channelRegistry.Delete(channelKey, info)
+	csNotice(rb, fmt.Sprintf(client.t("Channel %s is now unregistered"), channelKey))
+}

irc/getters.go

@@ -62,7 +62,7 @@ func (server *Server) DefaultChannelModes() modes.Modes {
 func (server *Server) ChannelRegistrationEnabled() bool {
 	server.configurableStateMutex.RLock()
 	defer server.configurableStateMutex.RUnlock()
-	return server.channelRegistrationEnabled
+	return server.config.Channels.Registration.Enabled
 }
 
 func (server *Server) AccountConfig() *AccountConfig {

irc/server.go

@@ -89,7 +89,6 @@ type ListenerWrapper struct {
 type Server struct {
 	accounts               *AccountManager
 	batches                *BatchManager
-	channelRegistrationEnabled bool
 	channels               *ChannelManager
 	channelRegistry        *ChannelRegistry
 	checkIdent             bool
@@ -955,9 +954,6 @@ func (server *Server) applyConfig(config *Config, initial bool) error {
 	server.operators = opers
 	server.checkIdent = config.Server.CheckIdent
 
-	// registration
-	server.channelRegistrationEnabled = config.Channels.Registration.Enabled
-
 	server.defaultChannelModes = ParseDefaultChannelModes(config)
 	server.configurableStateMutex.Unlock()