// Handle channel state change.
func (server *Server) handleChannelStateMessage(client *Client, msg *Message) {
chanstate := &mumbleproto.ChannelState{}
err := proto.Unmarshal(msg.buf, chanstate)
if err != nil {
client.Panic(err)
return
}
var channel *Channel
var parent *Channel
var ok bool
// Lookup channel for channel ID
if chanstate.ChannelId != nil {
channel, ok = server.Channels[int(*chanstate.ChannelId)]
if !ok {
client.Panic("Invalid channel specified in ChannelState message")
return
}
}
// Lookup parent
if chanstate.Parent != nil {
parent, ok = server.Channels[int(*chanstate.Parent)]
if !ok {
client.Panic("Invalid parent channel specified in ChannelState message")
return
}
}
// The server can't receive links through the links field in the ChannelState message,
// because clients are supposed to send modifications to a channel's link state through
// the links_add and links_remove fields.
// Make sure the links field is clear so we can transmit the channel's link state in our reply.
chanstate.Links = nil
var name string
var description string
// Extract the description and perform sanity checks.
if chanstate.Description != nil {
description, err = server.FilterText(*chanstate.Description)
if err != nil {
client.sendPermissionDeniedType(mumbleproto.PermissionDenied_TextTooLong)
return
}
}
// Extract the the name of channel and check whether it's valid.
// A valid channel name is a name that:
// a) Isn't already used by a channel at the same level as the channel itself (that is, channels
// that have a common parent can't have the same name.
// b) A name must be a valid name on the server (it must pass the channel name regexp)
if chanstate.Name != nil {
name = *chanstate.Name
// We don't allow renames for the root channel.
if channel != nil && channel.Id != 0 {
// Pick a parent. If the name change is part of a re-parent (a channel move),
// we must evaluate the parent variable. Since we're explicitly exlcuding the root
// channel from renames, channels that are the target of renames are guaranteed to have
// a parent.
evalp := parent
if evalp == nil {
evalp = channel.parent
}
for _, iter := range evalp.children {
if iter.Name == name {
client.sendPermissionDeniedType(mumbleproto.PermissionDenied_ChannelName)
return
}
}
}
}
// If the channel does not exist already, the ChannelState message is a create operation.
if channel == nil {
if parent == nil || len(name) == 0 {
return
}
// Check whether the client has permission to create the channel in parent.
perm := acl.Permission(acl.NonePermission)
if *chanstate.Temporary {
perm = acl.Permission(acl.TempChannelPermission)
} else {
perm = acl.Permission(acl.MakeChannelPermission)
}
if !acl.HasPermission(&parent.ACL, client, perm) {
client.sendPermissionDenied(client, parent, perm)
return
}
// Only registered users can create channels.
if !client.IsRegistered() && !client.HasCertificate() {
client.sendPermissionDeniedTypeUser(mumbleproto.PermissionDenied_MissingCertificate, client)
return
}
// We can't add channels to a temporary channel
if parent.IsTemporary() {
client.sendPermissionDeniedType(mumbleproto.PermissionDenied_TemporaryChannel)
return
}
key := ""
if len(description) > 0 {
key, err = blobStore.Put([]byte(description))
if err != nil {
server.Panicf("Blobstore error: %v", err)
}
}
// Add the new channel
channel = server.AddChannel(name)
channel.DescriptionBlob = key
channel.temporary = *chanstate.Temporary
channel.Position = int(*chanstate.Position)
parent.AddChild(channel)
// Add the creator to the channel's admin group
if client.IsRegistered() {
grp := acl.EmptyGroupWithName("admin")
grp.Add[client.UserId()] = true
channel.ACL.Groups["admin"] = grp
}
// If the client wouldn't have WritePermission in the just-created channel,
// add a +write ACL for the user's hash.
if !acl.HasPermission(&channel.ACL, client, acl.WritePermission) {
aclEntry := acl.ACL{}
aclEntry.ApplyHere = true
aclEntry.ApplySubs = true
if client.IsRegistered() {
aclEntry.UserId = client.UserId()
} else {
aclEntry.Group = "$" + client.CertHash()
}
aclEntry.Deny = acl.Permission(acl.NonePermission)
aclEntry.Allow = acl.Permission(acl.WritePermission | acl.TraversePermission)
channel.ACL.ACLs = append(channel.ACL.ACLs, aclEntry)
server.ClearCaches()
}
chanstate.ChannelId = proto.Uint32(uint32(channel.Id))
// Broadcast channel add
server.broadcastProtoMessageWithPredicate(chanstate, func(client *Client) bool {
return client.Version < 0x10202
})
// Remove description if client knows how to handle blobs.
if chanstate.Description != nil && channel.HasDescription() {
chanstate.Description = nil
chanstate.DescriptionHash = channel.DescriptionBlobHashBytes()
}
server.broadcastProtoMessageWithPredicate(chanstate, func(client *Client) bool {
return client.Version >= 0x10202
})
// If it's a temporary channel, move the creator in there.
if channel.IsTemporary() {
userstate := &mumbleproto.UserState{}
userstate.Session = proto.Uint32(client.Session())
userstate.ChannelId = proto.Uint32(uint32(channel.Id))
server.userEnterChannel(client, channel, userstate)
server.broadcastProtoMessage(userstate)
}
} else {
// Edit existing channel.
// First, check whether the actor has the neccessary permissions.
// Name change.
if chanstate.Name != nil {
// The client can only rename the channel if it has WritePermission in the channel.
// Also, clients cannot change the name of the root channel.
if !acl.HasPermission(&channel.ACL, client, acl.WritePermission) || channel.Id == 0 {
client.sendPermissionDenied(client, channel, acl.WritePermission)
return
}
}
// Description change
if chanstate.Description != nil {
if !acl.HasPermission(&channel.ACL, client, acl.WritePermission) {
client.sendPermissionDenied(client, channel, acl.WritePermission)
return
}
}
// Position change
if chanstate.Position != nil {
if !acl.HasPermission(&channel.ACL, client, acl.WritePermission) {
client.sendPermissionDenied(client, channel, acl.WritePermission)
return
}
}
// Parent change (channel move)
if parent != nil {
// No-op?
if parent == channel.parent {
return
}
// Make sure that channel we're operating on is not a parent of the new parent.
iter := parent
for iter != nil {
if iter == channel {
client.Panic("Illegal channel reparent")
return
}
iter = iter.parent
}
// A temporary channel must not have any subchannels, so deny it.
if parent.IsTemporary() {
client.sendPermissionDeniedType(mumbleproto.PermissionDenied_TemporaryChannel)
return
}
// To move a channel, the user must have WritePermission in the channel
if !acl.HasPermission(&channel.ACL, client, acl.WritePermission) {
client.sendPermissionDenied(client, channel, acl.WritePermission)
return
}
// And the user must also have MakeChannel permission in the new parent
if !acl.HasPermission(&parent.ACL, client, acl.MakeChannelPermission) {
client.sendPermissionDenied(client, parent, acl.MakeChannelPermission)
return
}
// If a sibling of parent already has this name, don't allow it.
for _, iter := range parent.children {
if iter.Name == channel.Name {
client.sendPermissionDeniedType(mumbleproto.PermissionDenied_ChannelName)
return
}
}
}
// Links
linkadd := []*Channel{}
linkremove := []*Channel{}
if len(chanstate.LinksAdd) > 0 || len(chanstate.LinksRemove) > 0 {
// Client must have permission to link
if !acl.HasPermission(&channel.ACL, client, acl.LinkChannelPermission) {
client.sendPermissionDenied(client, channel, acl.LinkChannelPermission)
return
}
// Add any valid channels to linkremove slice
for _, cid := range chanstate.LinksRemove {
if iter, ok := server.Channels[int(cid)]; ok {
linkremove = append(linkremove, iter)
}
}
// Add any valid channels to linkadd slice
for _, cid := range chanstate.LinksAdd {
if iter, ok := server.Channels[int(cid)]; ok {
if !acl.HasPermission(&iter.ACL, client, acl.LinkChannelPermission) {
client.sendPermissionDenied(client, iter, acl.LinkChannelPermission)
return
}
linkadd = append(linkadd, iter)
}
}
}
// Permission checks done!
// Channel move
if parent != nil {
channel.parent.RemoveChild(channel)
parent.AddChild(channel)
}
// Rename
if chanstate.Name != nil {
channel.Name = *chanstate.Name
}
// Description change
if chanstate.Description != nil {
if len(description) == 0 {
channel.DescriptionBlob = ""
} else {
key, err := blobStore.Put([]byte(description))
if err != nil {
server.Panicf("Blobstore error: %v", err)
}
channel.DescriptionBlob = key
}
}
// Position change
if chanstate.Position != nil {
channel.Position = int(*chanstate.Position)
}
// Add links
for _, iter := range linkadd {
server.LinkChannels(channel, iter)
}
// Remove links
for _, iter := range linkremove {
server.UnlinkChannels(channel, iter)
}
// Broadcast the update
server.broadcastProtoMessageWithPredicate(chanstate, func(client *Client) bool {
return client.Version < 0x10202
})
// Remove description blob when sending to 1.2.2 >= users. Only send the blob hash.
if channel.HasDescription() {
chanstate.Description = nil
chanstate.DescriptionHash = channel.DescriptionBlobHashBytes()
}
chanstate.DescriptionHash = channel.DescriptionBlobHashBytes()
server.broadcastProtoMessageWithPredicate(chanstate, func(client *Client) bool {
return client.Version >= 0x10202
})
}
// Update channel in datastore
if !channel.IsTemporary() {
server.UpdateFrozenChannel(channel, chanstate)
}
}
// ACL set/query
func (server *Server) handleAclMessage(client *Client, msg *Message) {
pacl := &mumbleproto.ACL{}
err := proto.Unmarshal(msg.buf, pacl)
if err != nil {
client.Panic(err)
return
}
// Look up the channel this ACL message operates on.
channel, ok := server.Channels[int(*pacl.ChannelId)]
if !ok {
return
}
// Does the user have permission to update or look at ACLs?
if !acl.HasPermission(&channel.ACL, client, acl.WritePermission) && !(channel.parent != nil && acl.HasPermission(&channel.parent.ACL, client, acl.WritePermission)) {
client.sendPermissionDenied(client, channel, acl.WritePermission)
return
}
reply := &mumbleproto.ACL{}
reply.ChannelId = proto.Uint32(uint32(channel.Id))
channels := []*Channel{}
users := map[int]bool{}
// Query the current ACL state for the channel
if pacl.Query != nil && *pacl.Query != false {
reply.InheritAcls = proto.Bool(channel.ACL.InheritACL)
// Walk the channel tree to get all relevant channels.
// (Stop if we reach a channel that doesn't have the InheritACL flag set)
iter := channel
for iter != nil {
channels = append([]*Channel{iter}, channels...)
if iter == channel || iter.ACL.InheritACL {
iter = iter.parent
} else {
iter = nil
}
}
// Construct the protobuf ChanACL objects corresponding to the ACLs defined
// in our channel list.
reply.Acls = []*mumbleproto.ACL_ChanACL{}
for _, iter := range channels {
for _, chanacl := range iter.ACL.ACLs {
if iter == channel || chanacl.ApplySubs {
mpacl := &mumbleproto.ACL_ChanACL{}
mpacl.Inherited = proto.Bool(iter != channel)
mpacl.ApplyHere = proto.Bool(chanacl.ApplyHere)
mpacl.ApplySubs = proto.Bool(chanacl.ApplySubs)
if chanacl.UserId >= 0 {
mpacl.UserId = proto.Uint32(uint32(chanacl.UserId))
users[chanacl.UserId] = true
} else {
mpacl.Group = proto.String(chanacl.Group)
}
mpacl.Grant = proto.Uint32(uint32(chanacl.Allow))
mpacl.Deny = proto.Uint32(uint32(chanacl.Deny))
reply.Acls = append(reply.Acls, mpacl)
}
}
}
parent := channel.parent
allnames := channel.ACL.GroupNames()
// Construct the protobuf ChanGroups that we send back to the client.
// Also constructs a usermap that is a set user ids from the channel's groups.
reply.Groups = []*mumbleproto.ACL_ChanGroup{}
for _, name := range allnames {
var (
group acl.Group
hasgroup bool
pgroup acl.Group
haspgroup bool
)
group, hasgroup = channel.ACL.Groups[name]
if parent != nil {
pgroup, haspgroup = parent.ACL.Groups[name]
}
mpgroup := &mumbleproto.ACL_ChanGroup{}
mpgroup.Name = proto.String(name)
mpgroup.Inherit = proto.Bool(true)
if hasgroup {
mpgroup.Inherit = proto.Bool(group.Inherit)
}
mpgroup.Inheritable = proto.Bool(true)
if hasgroup {
mpgroup.Inheritable = proto.Bool(group.Inheritable)
}
mpgroup.Inherited = proto.Bool(haspgroup && pgroup.Inheritable)
// Add the set of user ids that this group affects to the user map.
// This is used later on in this function to send the client a QueryUsers
// message that maps user ids to usernames.
if hasgroup {
toadd := map[int]bool{}
for uid, _ := range group.Add {
users[uid] = true
toadd[uid] = true
}
for uid, _ := range group.Remove {
users[uid] = true
delete(toadd, uid)
}
for uid, _ := range toadd {
mpgroup.Add = append(mpgroup.Add, uint32(uid))
}
}
if haspgroup {
for uid, _ := range pgroup.MembersInContext(&parent.ACL) {
users[uid] = true
mpgroup.InheritedMembers = append(mpgroup.InheritedMembers, uint32(uid))
}
}
reply.Groups = append(reply.Groups, mpgroup)
}
if err := client.sendMessage(reply); err != nil {
client.Panic(err)
return
}
// Map the user ids in the user map to usernames of users.
queryusers := &mumbleproto.QueryUsers{}
for uid, _ := range users {
user, ok := server.Users[uint32(uid)]
if !ok {
client.Printf("Invalid user id in ACL")
continue
}
queryusers.Ids = append(queryusers.Ids, uint32(uid))
queryusers.Names = append(queryusers.Names, user.Name)
}
if len(queryusers.Ids) > 0 {
client.sendMessage(queryusers)
}
// Set new groups and ACLs
} else {
// Get old temporary members
oldtmp := map[string]map[int]bool{}
for name, grp := range channel.ACL.Groups {
oldtmp[name] = grp.Temporary
}
// Clear current ACLs and groups
channel.ACL.ACLs = []acl.ACL{}
channel.ACL.Groups = map[string]acl.Group{}
// Add the received groups to the channel.
channel.ACL.InheritACL = *pacl.InheritAcls
for _, pbgrp := range pacl.Groups {
changroup := acl.EmptyGroupWithName(*pbgrp.Name)
changroup.Inherit = *pbgrp.Inherit
changroup.Inheritable = *pbgrp.Inheritable
for _, uid := range pbgrp.Add {
changroup.Add[int(uid)] = true
}
for _, uid := range pbgrp.Remove {
changroup.Remove[int(uid)] = true
}
if temp, ok := oldtmp[*pbgrp.Name]; ok {
changroup.Temporary = temp
}
channel.ACL.Groups[changroup.Name] = changroup
}
// Add the received ACLs to the channel.
for _, pbacl := range pacl.Acls {
chanacl := acl.ACL{}
chanacl.ApplyHere = *pbacl.ApplyHere
chanacl.ApplySubs = *pbacl.ApplySubs
if pbacl.UserId != nil {
chanacl.UserId = int(*pbacl.UserId)
} else {
chanacl.Group = *pbacl.Group
}
chanacl.Deny = acl.Permission(*pbacl.Deny & acl.AllPermissions)
chanacl.Allow = acl.Permission(*pbacl.Grant & acl.AllPermissions)
channel.ACL.ACLs = append(channel.ACL.ACLs, chanacl)
}
// Clear the Server's caches
server.ClearCaches()
// Regular user?
if !acl.HasPermission(&channel.ACL, client, acl.WritePermission) && client.IsRegistered() || client.HasCertificate() {
chanacl := acl.ACL{}
chanacl.ApplyHere = true
chanacl.ApplySubs = false
if client.IsRegistered() {
chanacl.UserId = client.UserId()
} else if client.HasCertificate() {
chanacl.Group = "$" + client.CertHash()
}
chanacl.Deny = acl.Permission(acl.NonePermission)
chanacl.Allow = acl.Permission(acl.WritePermission | acl.TraversePermission)
channel.ACL.ACLs = append(channel.ACL.ACLs, chanacl)
server.ClearCaches()
}
// Update freezer
server.UpdateFrozenChannelACLs(channel)
}
}