--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_privacy_lists/mod_privacy_lists.lua	Sun Jul 27 14:38:04 2014 +0100
@@ -0,0 +1,448 @@
+-- Prosody IM
+-- Copyright (C) 2009-2010 Matthew Wild
+-- Copyright (C) 2009-2010 Waqas Hussain
+-- Copyright (C) 2009 Thilo Cestonaro
+-- 
+-- This project is MIT/X11 licensed. Please see the
+-- COPYING file in the source package for more information.
+--
+
+module:add_feature("jabber:iq:privacy");
+
+local st = require "util.stanza";
+local bare_sessions, full_sessions = prosody.bare_sessions, prosody.full_sessions;
+local util_Jid = require "util.jid";
+local jid_bare = util_Jid.bare;
+local jid_split, jid_join = util_Jid.split, util_Jid.join;
+local load_roster = require "core.rostermanager".load_roster;
+local to_number = tonumber;
+
+local privacy_storage = module:open_store();
+
+function isListUsed(origin, name, privacy_lists)
+	local user = bare_sessions[origin.username.."@"..origin.host];
+	if user then
+		for resource, session in pairs(user.sessions) do
+			if resource ~= origin.resource then
+				if session.activePrivacyList == name then
+					return true;
+				elseif session.activePrivacyList == nil and privacy_lists.default == name then
+					return true;
+				end
+			end
+		end
+	end
+end
+
+function isAnotherSessionUsingDefaultList(origin)
+	local user = bare_sessions[origin.username.."@"..origin.host];
+	if user then
+		for resource, session in pairs(user.sessions) do
+			if resource ~= origin.resource and session.activePrivacyList == nil then
+				return true;
+			end
+		end
+	end
+end
+
+function declineList(privacy_lists, origin, stanza, which)
+	if which == "default" then
+		if isAnotherSessionUsingDefaultList(origin) then
+			return { "cancel", "conflict", "Another session is online and using the default list."};
+		end
+		privacy_lists.default = nil;
+		origin.send(st.reply(stanza));
+	elseif which == "active" then
+		origin.activePrivacyList = nil;
+		origin.send(st.reply(stanza));
+	else
+		return {"modify", "bad-request", "Neither default nor active list specifed to decline."};
+	end
+	return true;
+end
+
+function activateList(privacy_lists, origin, stanza, which, name)
+	local list = privacy_lists.lists[name];
+
+	if which == "default" and list then
+		if isAnotherSessionUsingDefaultList(origin) then
+			return {"cancel", "conflict", "Another session is online and using the default list."};
+		end
+		privacy_lists.default = name;
+		origin.send(st.reply(stanza));
+	elseif which == "active" and list then
+		origin.activePrivacyList = name;
+		origin.send(st.reply(stanza));
+	elseif not list then
+		return {"cancel", "item-not-found", "No such list: "..name};
+	else
+		return {"modify", "bad-request", "No list chosen to be active or default."};
+	end
+	return true;
+end
+
+function deleteList(privacy_lists, origin, stanza, name)
+	local list = privacy_lists.lists[name];
+
+	if list then
+		if isListUsed(origin, name, privacy_lists) then
+			return {"cancel", "conflict", "Another session is online and using the list which should be deleted."};
+		end
+		if privacy_lists.default == name then
+			privacy_lists.default = nil;
+		end
+		if origin.activePrivacyList == name then
+			origin.activePrivacyList = nil;
+		end
+		privacy_lists.lists[name] = nil;
+		origin.send(st.reply(stanza));
+		return true;
+	end
+	return {"modify", "bad-request", "Not existing list specifed to be deleted."};
+end
+
+function createOrReplaceList (privacy_lists, origin, stanza, name, entries)
+	local bare_jid = origin.username.."@"..origin.host;
+	
+	if privacy_lists.lists == nil then
+		privacy_lists.lists = {};
+	end
+
+	local list = {};
+	privacy_lists.lists[name] = list;
+
+	local orderCheck = {};
+	list.name = name;
+	list.items = {};
+
+	for _,item in ipairs(entries) do
+		if to_number(item.attr.order) == nil or to_number(item.attr.order) < 0 or orderCheck[item.attr.order] ~= nil then
+			return {"modify", "bad-request", "Order attribute not valid."};
+		end
+		
+		if item.attr.type ~= nil and item.attr.type ~= "jid" and item.attr.type ~= "subscription" and item.attr.type ~= "group" then
+			return {"modify", "bad-request", "Type attribute not valid."};
+		end
+		
+		local tmp = {};
+		orderCheck[item.attr.order] = true;
+		
+		tmp["type"] = item.attr.type;
+		tmp["value"] = item.attr.value;
+		tmp["action"] = item.attr.action;
+		tmp["order"] = to_number(item.attr.order);
+		tmp["presence-in"] = false;
+		tmp["presence-out"] = false;
+		tmp["message"] = false;
+		tmp["iq"] = false;
+		
+		if #item.tags > 0 then
+			for _,tag in ipairs(item.tags) do
+				tmp[tag.name] = true;
+			end
+		end
+		
+		if tmp.type == "subscription" then
+			if	tmp.value ~= "both" and
+				tmp.value ~= "to" and
+				tmp.value ~= "from" and
+				tmp.value ~= "none" then
+				return {"cancel", "bad-request", "Subscription value must be both, to, from or none."};
+			end
+		end
+		
+		if tmp.action ~= "deny" and tmp.action ~= "allow" then
+			return {"cancel", "bad-request", "Action must be either deny or allow."};
+		end
+		list.items[#list.items + 1] = tmp;
+	end
+	
+	table.sort(list, function(a, b) return a.order < b.order; end);
+
+	origin.send(st.reply(stanza));
+	if bare_sessions[bare_jid] ~= nil then
+		local iq = st.iq ( { type = "set", id="push1" } );
+		iq:tag ("query", { xmlns = "jabber:iq:privacy" } );
+		iq:tag ("list", { name = list.name } ):up();
+		iq:up();
+		for resource, session in pairs(bare_sessions[bare_jid].sessions) do
+			iq.attr.to = bare_jid.."/"..resource
+			session.send(iq);
+		end
+	else
+		return {"cancel", "bad-request", "internal error."};
+	end
+	return true;
+end
+
+function getList(privacy_lists, origin, stanza, name)
+	local reply = st.reply(stanza);
+	reply:tag("query", {xmlns="jabber:iq:privacy"});
+
+	if name == nil then
+		if privacy_lists.lists then
+			if origin.activePrivacyList then
+				reply:tag("active", {name=origin.activePrivacyList}):up();
+			end
+			if privacy_lists.default then
+				reply:tag("default", {name=privacy_lists.default}):up();
+			end
+			for name,list in pairs(privacy_lists.lists) do
+				reply:tag("list", {name=name}):up();
+			end
+		end
+	else
+		local list = privacy_lists.lists[name];
+		if list then
+			reply = reply:tag("list", {name=list.name});
+			for _,item in ipairs(list.items) do
+				reply:tag("item", {type=item.type, value=item.value, action=item.action, order=item.order});
+				if item["message"] then reply:tag("message"):up(); end
+				if item["iq"] then reply:tag("iq"):up(); end
+				if item["presence-in"] then reply:tag("presence-in"):up(); end
+				if item["presence-out"] then reply:tag("presence-out"):up(); end
+				reply:up();
+			end
+		else
+			return {"cancel", "item-not-found", "Unknown list specified."};
+		end
+	end
+	
+	origin.send(reply);
+	return true;
+end
+
+module:hook("iq/bare/jabber:iq:privacy:query", function(data)
+	local origin, stanza = data.origin, data.stanza;
+	
+	if stanza.attr.to == nil then -- only service requests to own bare JID
+		local query = stanza.tags[1]; -- the query element
+		local valid = false;
+		local privacy_lists = privacy_storage:get(origin.username) or { lists = {} };
+
+		if privacy_lists.lists[1] then -- Code to migrate from old privacy lists format, remove in 0.8
+			module:log("info", "Upgrading format of stored privacy lists for %s@%s", origin.username, origin.host);
+			local lists = privacy_lists.lists;
+			for idx, list in ipairs(lists) do
+				lists[list.name] = list;
+				lists[idx] = nil;
+			end
+		end
+
+		if stanza.attr.type == "set" then
+			if #query.tags == 1 then --  the <query/> element MUST NOT include more than one child element
+				for _,tag in ipairs(query.tags) do
+					if tag.name == "active" or tag.name == "default" then
+						if tag.attr.name == nil then -- Client declines the use of active / default list
+							valid = declineList(privacy_lists, origin, stanza, tag.name);
+						else -- Client requests change of active / default list
+							valid = activateList(privacy_lists, origin, stanza, tag.name, tag.attr.name);
+						end
+					elseif tag.name == "list" and tag.attr.name then -- Client adds / edits a privacy list
+						if #tag.tags == 0 then -- Client removes a privacy list
+							valid = deleteList(privacy_lists, origin, stanza, tag.attr.name);
+						else -- Client edits a privacy list
+							valid = createOrReplaceList(privacy_lists, origin, stanza, tag.attr.name, tag.tags);
+						end
+					end
+				end
+			end
+		elseif stanza.attr.type == "get" then
+			local name = nil;
+			local listsToRetrieve = 0;
+			if #query.tags >= 1 then
+				for _,tag in ipairs(query.tags) do
+					if tag.name == "list" then -- Client requests a privacy list from server
+						name = tag.attr.name;
+						listsToRetrieve = listsToRetrieve + 1;
+					end
+				end
+			end
+			if listsToRetrieve == 0 or listsToRetrieve == 1 then
+				valid = getList(privacy_lists, origin, stanza, name);
+			end
+		end
+
+		if valid ~= true then
+			valid = valid or { "cancel", "bad-request", "Couldn't understand request" };
+			if valid[1] == nil then
+				valid[1] = "cancel";
+			end
+			if valid[2] == nil then
+				valid[2] = "bad-request";
+			end
+			origin.send(st.error_reply(stanza, valid[1], valid[2], valid[3]));
+		else
+			privacy_storage:set(origin.username, privacy_lists);
+		end
+		return true;
+	end
+end);
+
+function checkIfNeedToBeBlocked(e, session)
+	local origin, stanza = e.origin, e.stanza;
+	local privacy_lists = privacy_storage:get(session.username) or {};
+	local bare_jid = session.username.."@"..session.host;
+	local to = stanza.attr.to or bare_jid;
+	local from = stanza.attr.from;
+	
+	local is_to_user = bare_jid == jid_bare(to);
+	local is_from_user = bare_jid == jid_bare(from);
+	
+	--module:log("debug", "stanza: %s, to: %s, from: %s", tostring(stanza.name), tostring(to), tostring(from));
+	
+	if privacy_lists.lists == nil or
+		not (session.activePrivacyList or privacy_lists.default)
+	then
+		return; -- Nothing to block, default is Allow all
+	end
+	if is_from_user and is_to_user then
+		--module:log("debug", "Not blocking communications between user's resources");
+		return; -- from one of a user's resource to another => HANDS OFF!
+	end
+	
+	local listname = session.activePrivacyList;
+	if listname == nil then
+		listname = privacy_lists.default; -- no active list selected, use default list
+	end
+	local list = privacy_lists.lists[listname];
+	if not list then -- should never happen
+		module:log("warn", "given privacy list not found. name: %s for user %s", listname, bare_jid);
+		return;
+	end
+	for _,item in ipairs(list.items) do
+		local apply = false;
+		local block = false;
+		if (
+			(stanza.name == "message" and item.message) or
+			(stanza.name == "iq" and item.iq) or
+			(stanza.name == "presence" and is_to_user and item["presence-in"]) or
+			(stanza.name == "presence" and is_from_user and item["presence-out"]) or
+			(item.message == false and item.iq == false and item["presence-in"] == false and item["presence-out"] == false)
+		) then
+			apply = true;
+		end
+		if apply then
+			local evilJid = {};
+			apply = false;
+			if is_to_user then
+				--module:log("debug", "evil jid is (from): %s", from);
+				evilJid.node, evilJid.host, evilJid.resource = jid_split(from);
+			else
+				--module:log("debug", "evil jid is (to): %s", to);
+				evilJid.node, evilJid.host, evilJid.resource = jid_split(to);
+			end
+			if	item.type == "jid" and
+				(evilJid.node and evilJid.host and evilJid.resource and item.value == evilJid.node.."@"..evilJid.host.."/"..evilJid.resource) or
+				(evilJid.node and evilJid.host and item.value == evilJid.node.."@"..evilJid.host) or
+				(evilJid.host and evilJid.resource and item.value == evilJid.host.."/"..evilJid.resource) or
+				(evilJid.host and item.value == evilJid.host) then
+				apply = true;
+				block = (item.action == "deny");
+			elseif item.type == "group" then
+				local roster = load_roster(session.username, session.host);
+				local roster_entry = roster[jid_join(evilJid.node, evilJid.host)];
+				if roster_entry then
+					local groups = roster_entry.groups;
+					for group in pairs(groups) do
+						if group == item.value then
+							apply = true;
+							block = (item.action == "deny");
+							break;
+						end
+					end
+				end
+			elseif item.type == "subscription" then -- we need a valid bare evil jid
+				local roster = load_roster(session.username, session.host);
+				local roster_entry = roster[jid_join(evilJid.node, evilJid.host)];
+				if (not(roster_entry) and item.value == "none")
+				   or (roster_entry and roster_entry.subscription == item.value) then
+					apply = true;
+					block = (item.action == "deny");
+				end
+			elseif item.type == nil then
+				apply = true;
+				block = (item.action == "deny");
+			end
+		end
+		if apply then
+			if block then
+				-- drop and not bounce groupchat messages, otherwise users will get kicked
+				if stanza.attr.type == "groupchat" then
+					return true;
+				end
+				module:log("debug", "stanza blocked: %s, to: %s, from: %s", tostring(stanza.name), tostring(to), tostring(from));
+				if stanza.name == "message" then
+					origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
+				elseif stanza.name == "iq" and (stanza.attr.type == "get" or stanza.attr.type == "set") then
+					origin.send(st.error_reply(stanza, "cancel", "service-unavailable"));
+				end
+				return true; -- stanza blocked !
+			else
+				--module:log("debug", "stanza explicitly allowed!")
+				return;
+			end
+		end
+	end
+end
+
+function preCheckIncoming(e)
+	local session;
+	if e.stanza.attr.to ~= nil then
+		local node, host, resource = jid_split(e.stanza.attr.to);
+		if node == nil or host == nil then
+			return;
+		end
+		if resource == nil then
+			local prio = 0;
+			if bare_sessions[node.."@"..host] ~= nil then
+				for resource, session_ in pairs(bare_sessions[node.."@"..host].sessions) do
+					if session_.priority ~= nil and session_.priority > prio then
+						session = session_;
+						prio = session_.priority;
+					end
+				end
+			end
+		else
+			session = full_sessions[node.."@"..host.."/"..resource];
+		end
+		if session ~= nil then
+			return checkIfNeedToBeBlocked(e, session);
+		else
+			--module:log("debug", "preCheckIncoming: Couldn't get session for jid: %s@%s/%s", tostring(node), tostring(host), tostring(resource));
+		end
+	end
+end
+
+function preCheckOutgoing(e)
+	local session = e.origin;
+	if e.stanza.attr.from == nil then
+		e.stanza.attr.from = session.username .. "@" .. session.host;
+		if session.resource ~= nil then
+		 	e.stanza.attr.from = e.stanza.attr.from .. "/" .. session.resource;
+		end
+	end
+	if session.username then -- FIXME do properly
+		return checkIfNeedToBeBlocked(e, session);
+	end
+end
+
+module:hook("pre-message/full", preCheckOutgoing, 500);
+module:hook("pre-message/bare", preCheckOutgoing, 500);
+module:hook("pre-message/host", preCheckOutgoing, 500);
+module:hook("pre-iq/full", preCheckOutgoing, 500);
+module:hook("pre-iq/bare", preCheckOutgoing, 500);
+module:hook("pre-iq/host", preCheckOutgoing, 500);
+module:hook("pre-presence/full", preCheckOutgoing, 500);
+module:hook("pre-presence/bare", preCheckOutgoing, 500);
+module:hook("pre-presence/host", preCheckOutgoing, 500);
+
+module:hook("message/full", preCheckIncoming, 500);
+module:hook("message/bare", preCheckIncoming, 500);
+module:hook("message/host", preCheckIncoming, 500);
+module:hook("iq/full", preCheckIncoming, 500);
+module:hook("iq/bare", preCheckIncoming, 500);
+module:hook("iq/host", preCheckIncoming, 500);
+module:hook("presence/full", preCheckIncoming, 500);
+module:hook("presence/bare", preCheckIncoming, 500);
+module:hook("presence/host", preCheckIncoming, 500);