File

util/dataforms.lua @ 13652:a08065207ef0

net.server_epoll: Call :shutdown() on TLS sockets when supported Comment from Matthew: This fixes a potential issue where the Prosody process gets blocked on sockets waiting for them to close. Unlike non-TLS sockets, closing a TLS socket sends layer 7 data, and this can cause problems for sockets which are in the process of being cleaned up. This depends on LuaSec changes which are not yet upstream. From Martijn's original email: So first my analysis of luasec. in ssl.c the socket is put into blocking mode right before calling SSL_shutdown() inside meth_destroy(). My best guess to why this is is because meth_destroy is linked to the __close and __gc methods, which can't exactly be called multiple times and luasec does want to make sure that a tls session is shutdown as clean as possible. I can't say I disagree with this reasoning and don't want to change this behaviour. My solution to this without changing the current behaviour is to introduce a shutdown() method. I am aware that this overlaps in a conflicting way with tcp's shutdown method, but it stays close to the OpenSSL name. This method calls SSL_shutdown() in the current (non)blocking mode of the underlying socket and returns a boolean whether or not the shutdown is completed (matching SSL_shutdown()'s 0 or 1 return values), and returns the familiar ssl_ioerror() strings on error with a false for completion. This error can then be used to determine if we have wantread/wantwrite to finalize things. Once meth_shutdown() has been called once a shutdown flag will be set, which indicates to meth_destroy() that the SSL_shutdown() has been handled by the application and it shouldn't be needed to set the socket to blocking mode. I've left the SSL_shutdown() call in the LSEC_STATE_CONNECTED to prevent TOCTOU if the application reaches a timeout for the shutdown code, which might allow SSL_shutdown() to clean up anyway at the last possible moment. Another thing I've changed to luasec is the call to socket_setblocking() right before calling close(2) in socket_destroy() in usocket.c. According to the latest POSIX[0]: Note that the requirement for close() on a socket to block for up to the current linger interval is not conditional on the O_NONBLOCK setting. Which I read to mean that removing O_NONBLOCK on the socket before close doesn't impact the behaviour and only causes noise in system call tracers. I didn't touch the windows bits of this, since I don't do windows. For the prosody side of things I've made the TLS shutdown bits resemble interface:onwritable(), and put it under a combined guard of self._tls and self.conn.shutdown. The self._tls bit is there to prevent getting stuck on this condition, and self.conn.shutdown is there to prevent the code being called by instances where the patched luasec isn't deployed. The destroy() method can be called from various places and is read by me as the "we give up" error path. To accommodate for these unexpected entrypoints I've added a single call to self.conn:shutdown() to prevent the socket being put into blocking mode. I have no expectations that there is any other use here. Same as previous, the self.conn.shutdown check is there to make sure it's not called on unpatched luasec deployments and self._tls is there to make sure we don't call shutdown() on tcp sockets. I wouldn't recommend logging of the conn:shutdown() error inside close(), since a lot of clients simply close the connection before SSL_shutdown() is done.
author Martijn van Duren <martijn@openbsd.org>
date Thu, 06 Feb 2025 15:04:38 +0000
parent 12975:d10957394a3c
line wrap: on
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-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local setmetatable = setmetatable;
local ipairs = ipairs;
local type, next = type, next;
local tonumber = tonumber;
local tostring = tostring;
local t_concat = table.concat;
local st = require "prosody.util.stanza";
local jid_prep = require "prosody.util.jid".prep;
local datetime = require "prosody.util.datetime";

local _ENV = nil;
-- luacheck: std none

local xmlns_forms = 'jabber:x:data';
local xmlns_validate = 'http://jabber.org/protocol/xdata-validate';

local form_t = {};
local form_mt = { __index = form_t };

local function new(layout)
	return setmetatable(layout, form_mt);
end

function form_t.form(layout, data, formtype)
	if not formtype then formtype = "form" end
	local form = st.stanza("x", { xmlns = xmlns_forms, type = formtype });
	if formtype == "cancel" then
		return form;
	end
	if formtype ~= "submit" then
		if layout.title then
			form:tag("title"):text(layout.title):up();
		end
		if layout.instructions then
			form:tag("instructions"):text(layout.instructions):up();
		end
	end
	for _, field in ipairs(layout) do
		local field_type = field.type or "text-single";
		-- Add field tag
		form:tag("field", { type = field_type, var = field.var or field.name, label = formtype ~= "submit" and field.label or nil });

		if formtype ~= "submit" then
			if field.desc then
				form:text_tag("desc", field.desc);
			end
		end

		if formtype == "form" and field.datatype then
			form:tag("validate", { xmlns = xmlns_validate, datatype = field.datatype });
			if field.range_min or field.range_max then
				form:tag("range", {
						min = field.range_min and tostring(field.range_min),
						max = field.range_max and tostring(field.range_max),
					}):up();
			end
			-- <basic/> assumed
			form:up();
		end


		local value = field.value;
		local options = field.options;

		if data and data[field.name] ~= nil then
			value = data[field.name];

			if formtype == "form" and type(value) == "table"
				and (field_type == "list-single" or field_type == "list-multi") then
				-- Allow passing dynamically generated options as values
				options, value = value, nil;
			end
		end

		if formtype == "form" and options then
			local defaults = {};
			for _, val in ipairs(options) do
				if type(val) == "table" then
					form:tag("option", { label = val.label }):tag("value"):text(val.value):up():up();
					if val.default then
						defaults[#defaults+1] = val.value;
					end
				else
					form:tag("option", { label= val }):tag("value"):text(val):up():up();
				end
			end
			if not value then
				if field_type == "list-single" then
					value = defaults[1];
				elseif field_type == "list-multi" then
					value = defaults;
				end
			end
		end

		if value ~= nil then
			if type(value) == "number" then
				if field.datatype == "xs:dateTime" then
					value = datetime.datetime(value);
				elseif field_type == "boolean" then
					value = value ~= 0;
				elseif field.datatype == "xs:double" or field.datatype == "xs:decimal" then
					value = ("%f"):format(value);
				else
					value = ("%d"):format(value);
				end
			end
			-- Add value, depending on type
			if field_type == "hidden" then
				if type(value) == "table" then
					-- Assume an XML snippet
					form:tag("value")
						:add_child(value)
						:up();
				else
					form:tag("value"):text(value):up();
				end
			elseif field_type == "boolean" then
				form:tag("value"):text((value and "1") or "0"):up();
			elseif field_type == "fixed" then
				form:tag("value"):text(value):up();
			elseif field_type == "jid-multi" then
				for _, jid in ipairs(value) do
					form:tag("value"):text(jid):up();
				end
			elseif field_type == "jid-single" then
				form:tag("value"):text(value):up();
			elseif field_type == "text-single" or field_type == "text-private" then
				form:tag("value"):text(value):up();
			elseif field_type == "text-multi" then
				-- Split into multiple <value> tags, one for each line
				for line in value:gmatch("([^\r\n]+)\r?\n*") do
					form:tag("value"):text(line):up();
				end
			elseif field_type == "list-single" then
				form:tag("value"):text(value):up();
			elseif field_type == "list-multi" then
				for _, val in ipairs(value) do
					form:tag("value"):text(val):up();
				end
			end
		end

		local media = field.media;
		if media then
			form:tag("media", { xmlns = "urn:xmpp:media-element", height = ("%d"):format(media.height), width = ("%d"):format(media.width) });
			for _, val in ipairs(media) do
				form:tag("uri", { type = val.type }):text(val.uri):up()
			end
			form:up();
		end

		if formtype == "form" and field.required then
			form:tag("required"):up();
		end

		-- Jump back up to list of fields
		form:up();
	end
	return form;
end

local field_readers = {};
local data_validators = {};

function form_t.data(layout, stanza, current)
	local data = {};
	local errors = {};
	local present = {};

	for _, field in ipairs(layout) do
		local tag;
		for field_tag in stanza:childtags("field") do
			if (field.var or field.name) == field_tag.attr.var then
				tag = field_tag;
				break;
			end
		end

		if not tag then
			if current and current[field.name] ~= nil then
				data[field.name] = current[field.name];
			elseif field.required then
				errors[field.name] = "Required value missing";
			end
		elseif field.name then
			present[field.name] = true;
			local reader = field_readers[field.type];
			if reader then
				local value, err = reader(tag, field.required);
				local validator = field.datatype and data_validators[field.datatype];
				if value ~= nil and validator then
					local valid, ret = validator(value, field);
					if valid then
						value = ret;
					else
						value, err = nil, ret or ("Invalid value for data of type " .. field.datatype);
					end
				end
				data[field.name], errors[field.name] = value, err;
			end
		end
	end
	if next(errors) then
		return data, errors, present;
	end
	return data, nil, present;
end

local function simple_text(field_tag, required)
	local data = field_tag:get_child_text("value");
	-- XEP-0004 does not say if an empty string is acceptable for a required value
	-- so we will follow HTML5 which says that empty string means missing
	if required and (data == nil or data == "") then
		return nil, "Required value missing";
	end
	return data; -- Return whatever get_child_text returned, even if empty string
end

field_readers["text-single"] = simple_text;

field_readers["text-private"] = simple_text;

field_readers["jid-single"] =
	function (field_tag, required)
		local raw_data, err = simple_text(field_tag, required);
		if not raw_data then return raw_data, err; end
		local data = jid_prep(raw_data);
		if not data then
			return nil, "Invalid JID: " .. raw_data;
		end
		return data;
	end

field_readers["jid-multi"] =
	function (field_tag, required)
		local result = {};
		local err = {};
		for value_tag in field_tag:childtags("value") do
			local raw_value = value_tag:get_text();
			local value = jid_prep(raw_value);
			result[#result+1] = value;
			if raw_value and not value then
				err[#err+1] = ("Invalid JID: " .. raw_value);
			end
		end
		if #result > 0 then
			return result, (#err > 0 and t_concat(err, "\n") or nil);
		elseif required then
			return nil, "Required value missing";
		end
	end

field_readers["list-multi"] =
	function (field_tag, required)
		local result = {};
		for value in field_tag:childtags("value") do
			result[#result+1] = value:get_text();
		end
		if #result > 0 then
			return result;
		elseif required then
			return nil, "Required value missing";
		end
	end

field_readers["text-multi"] =
	function (field_tag, required)
		local data, err = field_readers["list-multi"](field_tag, required);
		if data then
			data = t_concat(data, "\n");
		end
		return data, err;
	end

field_readers["list-single"] = simple_text;

local boolean_values = {
	["1"] = true, ["true"] = true,
	["0"] = false, ["false"] = false,
};

field_readers["boolean"] =
	function (field_tag, required)
		local raw_value, err = simple_text(field_tag, required);
		if not raw_value then return raw_value, err; end
		local value = boolean_values[raw_value];
		if value == nil then
			return nil, "Invalid boolean representation:" .. raw_value;
		end
		return value;
	end

field_readers["hidden"] =
	function (field_tag)
		return field_tag:get_child_text("value");
	end

data_validators["xs:integer"] =
	function (data, field)
		local n = tonumber(data);
		if not n then
			return false, "not a number";
		elseif n % 1 ~= 0 then
			return false, "not an integer";
		end
		if field.range_max and n > field.range_max then
			return false, "out of bounds";
		elseif field.range_min and n < field.range_min then
			return false, "out of bounds";
		end
		return true, n;
	end

data_validators["pubsub:integer-or-max"] =
	function (data, field)
		if data == "max" then
			return true, data;
		else
			return data_validators["xs:integer"](data, field);
		end
	end

data_validators["xs:dateTime"] =
	function(data, field) -- luacheck: ignore 212/field
		local n = datetime.parse(data);
		if not n then return false, "invalid timestamp"; end
		return true, n;
	end


local function get_form_type(form)
	if not st.is_stanza(form) then
		return nil, "not a stanza object";
	elseif form.attr.xmlns ~= "jabber:x:data" or form.name ~= "x" then
		return nil, "not a dataform element";
	end
	for field in form:childtags("field") do
		if field.attr.var == "FORM_TYPE" then
			return field:get_child_text("value");
		end
	end
	return "";
end

return {
	new = new;
	get_type = get_form_type;
};


--[=[

Layout:
{

	title = "MUC Configuration",
	instructions = [[Use this form to configure options for this MUC room.]],

	{ name = "FORM_TYPE", type = "hidden", required = true };
	{ name = "field-name", type = "field-type", required = false };
}


--]=]