Merge pull request #270 from slingamn/amode.1

frontend for persistent account modes in channels

irc/channel.go

@@ -232,13 +232,7 @@ func (channel *Channel) ClientIsAtLeast(client *Client, permission modes.Mode) b
 
 	clientModes := channel.members[client]
 
-	// get voice, since it's not a part of ChannelPrivModes
+	for _, mode := range modes.ChannelUserModes {
-	if clientModes.HasMode(permission) {
-		return true
-	}
-
-	// check regular modes
-	for _, mode := range modes.ChannelPrivModes {
 		if clientModes.HasMode(mode) {
 			return true
 		}

irc/chanserv.go

@@ -5,6 +5,7 @@ package irc
 
 import (
 	"fmt"
+	"sort"
 	"strings"
 
 	"github.com/goshuirc/irc-go/ircfmt"
@@ -42,6 +43,17 @@ remembered.`,
 			helpShort:    `$bREGISTER$b lets you own a given channel.`,
 			authRequired: true,
 		},
+		"amode": {
+			handler: csAmodeHandler,
+			help: `Syntax: $bAMODE #channel [mode change] [account]$b
+
+AMODE lists or modifies persistent mode settings that affect channel members.
+For example, $bAMODE #channel +o dan$b grants the the holder of the "dan"
+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.`,
+		},
 	}
 )
 
@@ -50,6 +62,79 @@ func csNotice(rb *ResponseBuffer, text string) {
 	rb.Add(nil, "ChanServ", "NOTICE", rb.target.Nick(), text)
 }
 
+func csAmodeHandler(server *Server, client *Client, command, params string, rb *ResponseBuffer) {
+	channelName, modeChange := utils.ExtractParam(params)
+
+	channel := server.channels.Get(channelName)
+	if channel == nil {
+		csNotice(rb, client.t("Channel does not exist"))
+		return
+	} else if channel.Founder() == "" {
+		csNotice(rb, client.t("Channel is not registered"))
+		return
+	}
+
+	modeChanges, unknown := modes.ParseChannelModeChanges(strings.Fields(modeChange)...)
+	var change modes.ModeChange
+	if len(modeChanges) > 1 || len(unknown) > 0 {
+		csNotice(rb, client.t("Invalid mode change"))
+		return
+	} else if len(modeChanges) == 1 {
+		change = modeChanges[0]
+	} else {
+		change = modes.ModeChange{Op: modes.List}
+	}
+
+	// normalize and validate the account argument
+	accountIsValid := false
+	change.Arg, _ = CasefoldName(change.Arg)
+	switch change.Op {
+	case modes.List:
+		accountIsValid = true
+	case modes.Add:
+		// if we're adding a mode, the account must exist
+		if change.Arg != "" {
+			_, err := server.accounts.LoadAccount(change.Arg)
+			accountIsValid = (err == nil)
+		}
+	case modes.Remove:
+		// allow removal of accounts that may have been deleted
+		accountIsValid = (change.Arg != "")
+	}
+	if !accountIsValid {
+		csNotice(rb, client.t("Account does not exist"))
+		return
+	}
+
+	affectedModes, err := channel.ProcessAccountToUmodeChange(client, change)
+
+	if err == errInsufficientPrivs {
+		csNotice(rb, client.t("Insufficient privileges"))
+		return
+	} else if err != nil {
+		csNotice(rb, client.t("Internal error"))
+		return
+	}
+
+	switch change.Op {
+	case modes.List:
+		// sort the persistent modes in descending order of priority
+		sort.Slice(affectedModes, func(i, j int) bool {
+			return umodeGreaterThan(affectedModes[i].Mode, affectedModes[j].Mode)
+		})
+		csNotice(rb, fmt.Sprintf(client.t("Channel %s has %d persistent modes set"), channelName, len(affectedModes)))
+		for _, modeChange := range affectedModes {
+			csNotice(rb, fmt.Sprintf(client.t("Account %s receives mode +%s"), modeChange.Arg, string(modeChange.Mode)))
+		}
+	case modes.Add, modes.Remove:
+		if len(affectedModes) > 0 {
+			csNotice(rb, fmt.Sprintf(client.t("Successfully set mode %s"), change.String()))
+		} else {
+			csNotice(rb, client.t("Change was a no-op"))
+		}
+	}
+}
+
 func csOpHandler(server *Server, client *Client, command, params string, rb *ResponseBuffer) {
 	channelName, clientToOp := utils.ExtractParam(params)
 

irc/errors.go

@@ -34,6 +34,7 @@ var (
 	errNoExistingBan                  = errors.New("Ban does not exist")
 	errNoSuchChannel                  = errors.New("No such channel")
 	errRenamePrivsNeeded              = errors.New("Only chanops can rename channels")
+	errInsufficientPrivs              = errors.New("Insufficient privileges")
 	errSaslFail                       = errors.New("SASL failed")
 )
 

irc/modes.go

@@ -240,3 +240,79 @@ func (channel *Channel) ApplyChannelModeChanges(client *Client, isSamode bool, c
 
 	return applied
 }
+
+// tests whether l > r, in the channel-user mode ordering (e.g., Halfop > Voice)
+func umodeGreaterThan(l modes.Mode, r modes.Mode) bool {
+	for _, mode := range modes.ChannelUserModes {
+		if l == mode && r != mode {
+			return true
+		} else if r == mode {
+			return false
+		}
+	}
+	return false
+}
+
+// ProcessAccountToUmodeChange processes Add/Remove/List operations for channel persistent usermodes.
+func (channel *Channel) ProcessAccountToUmodeChange(client *Client, change modes.ModeChange) (results []modes.ModeChange, err error) {
+	umodeGEQ := func(l modes.Mode, r modes.Mode) bool {
+		return l == r || umodeGreaterThan(l, r)
+	}
+
+	account := client.Account()
+	isOperChange := client.HasRoleCapabs("chanreg")
+
+	channel.stateMutex.Lock()
+	defer channel.stateMutex.Unlock()
+
+	clientMode := channel.accountToUMode[account]
+	targetModeNow := channel.accountToUMode[change.Arg]
+	var targetModeAfter modes.Mode
+	if change.Op == modes.Add {
+		targetModeAfter = change.Mode
+	}
+
+	// operators and founders can do anything
+	hasPrivs := isOperChange || (account != "" && account == channel.registeredFounder)
+	// halfop and up can list, and do add/removes at levels <= their own
+	if change.Op == modes.List && umodeGEQ(clientMode, modes.Halfop) {
+		hasPrivs = true
+	} else if umodeGEQ(clientMode, modes.Halfop) && umodeGEQ(clientMode, targetModeNow) && umodeGEQ(clientMode, targetModeAfter) {
+		hasPrivs = true
+	}
+	if !hasPrivs {
+		return nil, errInsufficientPrivs
+	}
+
+	switch change.Op {
+	case modes.Add:
+		if targetModeNow != targetModeAfter {
+			channel.accountToUMode[change.Arg] = change.Mode
+			go client.server.channelRegistry.StoreChannel(channel, IncludeLists)
+			return []modes.ModeChange{change}, nil
+		}
+		return nil, nil
+	case modes.Remove:
+		if targetModeNow == change.Mode {
+			delete(channel.accountToUMode, change.Arg)
+			go client.server.channelRegistry.StoreChannel(channel, IncludeLists)
+			return []modes.ModeChange{change}, nil
+		}
+		return nil, nil
+	case modes.List:
+		result := make([]modes.ModeChange, len(channel.accountToUMode))
+		pos := 0
+		for account, mode := range channel.accountToUMode {
+			result[pos] = modes.ModeChange{
+				Mode: mode,
+				Arg:  account,
+				Op:   modes.Add,
+			}
+			pos++
+		}
+		return result, nil
+	default:
+		// shouldn't happen
+		return nil, errInvalidCharacter
+	}
+}

irc/modes/modes.go

@@ -147,6 +147,12 @@ var (
 		ChannelFounder, ChannelAdmin, ChannelOperator, Halfop,
 	}
 
+	// ChannelUserModes holds the list of all modes that can be applied to a user in a channel,
+	// including Voice, in descending order of precedence
+	ChannelUserModes = Modes{
+		ChannelFounder, ChannelAdmin, ChannelOperator, Halfop, Voice,
+	}
+
 	ChannelModePrefixes = map[Mode]string{
 		ChannelFounder:  "~",
 		ChannelAdmin:    "&",
@@ -176,20 +182,13 @@ func SplitChannelMembershipPrefixes(target string) (prefixes string, name string
 }
 
 // GetLowestChannelModePrefix returns the lowest channel prefix mode out of the given prefixes.
-func GetLowestChannelModePrefix(prefixes string) *Mode {
+func GetLowestChannelModePrefix(prefixes string) (lowest *Mode) {
-	var lowest *Mode
+	for i, mode := range ChannelUserModes {
-
+		if strings.Contains(prefixes, ChannelModePrefixes[mode]) {
-	if strings.Contains(prefixes, "+") {
+			lowest = &ChannelPrivModes[i]
-		lowest = &Voice
-	} else {
-		for i, mode := range ChannelPrivModes {
-			if strings.Contains(prefixes, ChannelModePrefixes[mode]) {
-				lowest = &ChannelPrivModes[i]
-			}
 		}
 	}
-
+	return
-	return lowest
 }
 
 //
@@ -304,15 +303,12 @@ func ParseChannelModeChanges(params ...string) (ModeChanges, map[rune]bool) {
 					break
 				}
 			}
-			for _, supportedMode := range ChannelPrivModes {
+			for _, supportedMode := range ChannelUserModes {
 				if rune(supportedMode) == mode {
 					isKnown = true
 					break
 				}
 			}
-			if mode == rune(Voice) {
-				isKnown = true
-			}
 			if !isKnown {
 				unknown[mode] = true
 				continue
@@ -405,14 +401,11 @@ func (set *ModeSet) Prefixes(isMultiPrefix bool) (prefixes string) {
 	defer set.RUnlock()
 
 	// add prefixes in order from highest to lowest privs
-	for _, mode := range ChannelPrivModes {
+	for _, mode := range ChannelUserModes {
 		if set.modes[mode] {
 			prefixes += ChannelModePrefixes[mode]
 		}
 	}
-	if set.modes[Voice] {
-		prefixes += ChannelModePrefixes[Voice]
-	}
 
 	if !isMultiPrefix && len(prefixes) > 1 {
 		prefixes = string(prefixes[0])

irc/modes/modes_test.go

@@ -8,6 +8,47 @@ import (
 	"testing"
 )
 
+func TestParseChannelModeChanges(t *testing.T) {
+	modes, unknown := ParseChannelModeChanges("+h", "wrmsr")
+	if len(unknown) > 0 {
+		t.Errorf("unexpected unknown mode change: %v", unknown)
+	}
+	expected := ModeChange{
+		Op:   Add,
+		Mode: Halfop,
+		Arg:  "wrmsr",
+	}
+	if len(modes) != 1 || modes[0] != expected {
+		t.Errorf("unexpected mode change: %v", modes)
+	}
+
+	modes, unknown = ParseChannelModeChanges("-v", "shivaram")
+	if len(unknown) > 0 {
+		t.Errorf("unexpected unknown mode change: %v", unknown)
+	}
+	expected = ModeChange{
+		Op:   Remove,
+		Mode: Voice,
+		Arg:  "shivaram",
+	}
+	if len(modes) != 1 || modes[0] != expected {
+		t.Errorf("unexpected mode change: %v", modes)
+	}
+
+	modes, unknown = ParseChannelModeChanges("+tx")
+	if len(unknown) != 1 || !unknown['x'] {
+		t.Errorf("expected that x is an unknown mode, instead: %v", unknown)
+	}
+	expected = ModeChange{
+		Op:   Add,
+		Mode: OpOnlyTopic,
+		Arg:  "",
+	}
+	if len(modes) != 1 || modes[0] != expected {
+		t.Errorf("unexpected mode change: %v", modes)
+	}
+}
+
 func TestSetMode(t *testing.T) {
 	set := NewModeSet()
 

irc/modes_test.go

@@ -36,3 +36,17 @@ func TestParseDefaultChannelModes(t *testing.T) {
 		}
 	}
 }
+
+func TestUmodeGreaterThan(t *testing.T) {
+	if !umodeGreaterThan(modes.Halfop, modes.Voice) {
+		t.Errorf("expected Halfop > Voice")
+	}
+
+	if !umodeGreaterThan(modes.Voice, modes.Mode(0)) {
+		t.Errorf("expected Voice > 0 (the zero value of modes.Mode)")
+	}
+
+	if umodeGreaterThan(modes.ChannelAdmin, modes.ChannelAdmin) {
+		t.Errorf("modes should not be greater than themselves")
+	}
+}

oragono.yaml

@@ -284,6 +284,7 @@ oper-classes:
             - "sajoin"
             - "samode"
             - "vhosts"
+            - "chanreg"
 
 # ircd operators
 opers: