view mod_firewall/actions.lib.lua @ 5256:44f7edd4f845

mod_http_oauth2: Reject non-local hosts in more code paths We're not issuing tokens for users on remote hosts, we can't even authenticate them since they're remote. Thus the host is always the local module.host so no need to pass around the host in most cases or use it for anything but enforcing the same host.
author Kim Alvefur <zash@zash.se>
date Thu, 16 Mar 2023 17:52:10 +0100
parents d0d251abf595
children 96dec7681af8
line wrap: on
line source

local unpack = table.unpack or unpack;

local interpolation = require "util.interpolation";
local template = interpolation.new("%b$$", function (s) return ("%q"):format(s) end);

--luacheck: globals meta idsafe
local action_handlers = {};


-- Takes an XML string and returns a code string that builds that stanza
-- using st.stanza()
local function compile_xml(data)
	local code = {};
	local first, short_close = true, nil;
	for tagline, text in data:gmatch("<([^>]+)>([^<]*)") do
		if tagline:sub(-1,-1) == "/" then
			tagline = tagline:sub(1, -2);
			short_close = true;
		end
		if tagline:sub(1,1) == "/" then
			code[#code+1] = (":up()");
		else
			local name, attr = tagline:match("^(%S*)%s*(.*)$");
			local attr_str = {};
			for k, _, v in attr:gmatch("(%S+)=([\"'])([^%2]-)%2") do
				if #attr_str == 0 then
					table.insert(attr_str, ", { ");
				else
					table.insert(attr_str, ", ");
				end
				if k:find("^%a%w*$") then
					table.insert(attr_str, string.format("%s = %q", k, v));
				else
					table.insert(attr_str, string.format("[%q] = %q", k, v));
				end
			end
			if #attr_str > 0 then
				table.insert(attr_str, " }");
			end
			if first then
				code[#code+1] = (string.format("st.stanza(%q %s)", name, #attr_str>0 and table.concat(attr_str) or ", nil"));
				first = nil;
			else
				code[#code+1] = (string.format(":tag(%q%s)", name, table.concat(attr_str)));
			end
		end
		if text and text:find("%S") then
			code[#code+1] = (string.format(":text(%q)", text));
		elseif short_close then
			short_close = nil;
			code[#code+1] = (":up()");
		end
	end
	return table.concat(code, "");
end

function action_handlers.PASS()
	return "do return pass_return end"
end

function action_handlers.DROP()
	return "do return true end";
end

function action_handlers.DEFAULT()
	return "do return false end";
end

function action_handlers.RETURN()
	return "do return end"
end

function action_handlers.STRIP(tag_desc)
	local code = {};
	local name, xmlns = tag_desc:match("^(%S+) (.+)$");
	if not name then
		name, xmlns = tag_desc, nil;
	end
	if name == "*" then
		name = nil;
	end
	code[#code+1] = ("local stanza_xmlns = stanza.attr.xmlns; ");
	code[#code+1] = "stanza:maptags(function (tag) if ";
	if name then
		code[#code+1] = ("tag.name == %q and "):format(name);
	end
	if xmlns then
		code[#code+1] = ("(tag.attr.xmlns or stanza_xmlns) == %q "):format(xmlns);
	else
		code[#code+1] = ("tag.attr.xmlns == stanza_xmlns ");
	end
	code[#code+1] = "then return nil; end return tag; end );";
	return table.concat(code);
end

function action_handlers.INJECT(tag)
	return "stanza:add_child("..compile_xml(tag)..")", { "st" };
end

local error_types = {
	["bad-request"] = "modify";
	["conflict"] = "cancel";
	["feature-not-implemented"] = "cancel";
	["forbidden"] = "auth";
	["gone"] = "cancel";
	["internal-server-error"] = "cancel";
	["item-not-found"] = "cancel";
	["jid-malformed"] = "modify";
	["not-acceptable"] = "modify";
	["not-allowed"] = "cancel";
	["not-authorized"] = "auth";
	["payment-required"] = "auth";
	["policy-violation"] = "modify";
	["recipient-unavailable"] = "wait";
	["redirect"] = "modify";
	["registration-required"] = "auth";
	["remote-server-not-found"] = "cancel";
	["remote-server-timeout"] = "wait";
	["resource-constraint"] = "wait";
	["service-unavailable"] = "cancel";
	["subscription-required"] = "auth";
	["undefined-condition"] = "cancel";
	["unexpected-request"] = "wait";
};


local function route_modify(make_new, to, drop)
	local reroute, deps = "session.send(newstanza)", { "st" };
	if to then
		reroute = ("newstanza.attr.to = %q; core_post_stanza(session, newstanza)"):format(to);
		deps[#deps+1] = "core_post_stanza";
	end
	return ([[do local newstanza = st.%s; %s;%s end]])
		:format(make_new, reroute, drop and " return true" or ""), deps;
end

function action_handlers.BOUNCE(with)
	local error = with and with:match("^%S+") or "service-unavailable";
	local error_type = error:match(":(%S+)");
	if not error_type then
		error_type = error_types[error] or "cancel";
	else
		error = error:match("^[^:]+");
	end
	error, error_type = string.format("%q", error), string.format("%q", error_type);
	local text = with and with:match(" %((.+)%)$");
	if text then
		text = string.format("%q", text);
	else
		text = "nil";
	end
	local route_modify_code, deps = route_modify(("error_reply(stanza, %s, %s, %s)"):format(error_type, error, text), nil, true);
	deps[#deps+1] = "type";
	deps[#deps+1] = "name";
	return [[if type == "error" or (name == "iq" and type == "result") then return true; end -- Don't reply to 'error' stanzas, or iq results
			]]..route_modify_code, deps;
end

function action_handlers.REDIRECT(where)
	return route_modify("clone(stanza)", where, true);
end

function action_handlers.COPY(where)
	return route_modify("clone(stanza)", where, false);
end

function action_handlers.REPLY(with)
	return route_modify(("reply(stanza):body(%q)"):format(with));
end

function action_handlers.FORWARD(where)
	local code = [[
		local newstanza = st.stanza("message", { to = %q, from = current_host }):tag("forwarded", { xmlns = "urn:xmpp:forward:0" });
		local tmp_stanza = st.clone(stanza); tmp_stanza.attr.xmlns = "jabber:client"; newstanza:add_child(tmp_stanza);
		core_post_stanza(session, newstanza);
	]];
	return code:format(where), { "core_post_stanza", "current_host" };
end

function action_handlers.LOG(string)
	local level = string:match("^%[(%a+)%]") or "info";
	string = string:gsub("^%[%a+%] ?", "");
	local meta_deps = {};
	local code = meta(("(session.log or log)(%q, '%%s', %q);"):format(level, string), meta_deps);
	return code, meta_deps;
end

function action_handlers.RULEDEP(dep)
	return "", { dep };
end

function action_handlers.EVENT(name)
	return ("fire_event(%q, event)"):format(name);
end

function action_handlers.JUMP_EVENT(name)
	return ("do return fire_event(%q, event); end"):format(name);
end

function action_handlers.JUMP_CHAIN(name)
	return template([[do
		local ret = fire_event($chain_event$, event);
		if ret ~= nil then
			if ret == false then
				log("debug", "Chain %q accepted stanza (ret %s)", $chain_name$, tostring(ret));
				return pass_return;
			end
			log("debug", "Chain %q rejected stanza (ret %s)", $chain_name$, tostring(ret));
			return ret;
		end
	end]], { chain_event = "firewall/chains/"..name, chain_name = name });
end

function action_handlers.MARK_ORIGIN(name)
	return [[session.firewall_marked_]]..idsafe(name)..[[ = current_timestamp;]], { "timestamp" };
end

function action_handlers.UNMARK_ORIGIN(name)
	return [[session.firewall_marked_]]..idsafe(name)..[[ = nil;]]
end

function action_handlers.MARK_USER(name)
	return [[if session.firewall_marks then session.firewall_marks.]]..idsafe(name)..[[ = current_timestamp; end]], { "timestamp" };
end

function action_handlers.UNMARK_USER(name)
	return [[if session.firewall_marks then session.firewall_marks.]]..idsafe(name)..[[ = nil; end]], { "timestamp" };
end

function action_handlers.ADD_TO(spec)
	local list_name, value = spec:match("(%S+) (.+)");
	local meta_deps = {};
	value = meta(("%q"):format(value), meta_deps);
	return ("list_%s:add(%s);"):format(list_name, value), { "list:"..list_name, unpack(meta_deps) };
end

function action_handlers.UNSUBSCRIBE_SENDER()
	return "rostermanager.unsubscribed(to_node, to_host, bare_from);\
	rostermanager.roster_push(to_node, to_host, bare_from);\
	core_post_stanza(session, st.presence({ from = bare_to, to = bare_from, type = \"unsubscribed\" }));",
	       { "rostermanager", "core_post_stanza", "st", "split_to", "bare_to", "bare_from" };
end

function action_handlers.REPORT_TO(spec)
	local where, reason, text = spec:match("^%s*(%S+) *(%S*) *(.*)$");
	if reason == "spam" then
		reason = "urn:xmpp:reporting:spam";
	elseif reason == "abuse" or not reason then
		reason = "urn:xmpp:reporting:abuse";
	end
	local code = [[
		local newstanza = st.stanza("message", { to = %q, from = current_host }):tag("forwarded", { xmlns = "urn:xmpp:forward:0" });
		local tmp_stanza = st.clone(stanza); tmp_stanza.attr.xmlns = "jabber:client"; newstanza:add_child(tmp_stanza):up();
		newstanza:tag("report", { xmlns = "urn:xmpp:reporting:1", reason = %q })
		do local text = %q; if text ~= "" then newstanza:text_tag("text", text); end end
		newstanza:up();
		core_post_stanza(session, newstanza);
	]];
	return code:format(where, reason, text), { "core_post_stanza", "current_host", "st" };
end

return action_handlers;