File

util/stanza.lua @ 5915:e6fed1d80116

Back out 1b0ac7950129, as SSLv3 appears to still be in moderate use on the network. Also, although obsolete, SSLv3 isn't documented to have any weaknesses that TLS 1.0 (the most common version used today) doesn't also have. Get your act together clients!
author Matthew Wild <mwild1@gmail.com>
date Tue, 12 Nov 2013 02:13:01 +0000
parent 5435:f56e449a63e3
child 5776:bd0ff8ae98a8
child 6466:6e67c73f730c
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 t_insert      =  table.insert;
local t_remove      =  table.remove;
local t_concat      =  table.concat;
local s_format      = string.format;
local s_match       =  string.match;
local tostring      =      tostring;
local setmetatable  =  setmetatable;
local pairs         =         pairs;
local ipairs        =        ipairs;
local type          =          type;
local s_gsub        =   string.gsub;
local s_sub         =    string.sub;
local s_find        =   string.find;
local os            =            os;

local do_pretty_printing = not os.getenv("WINDIR");
local getstyle, getstring;
if do_pretty_printing then
	local ok, termcolours = pcall(require, "util.termcolours");
	if ok then
		getstyle, getstring = termcolours.getstyle, termcolours.getstring;
	else
		do_pretty_printing = nil;
	end
end

local xmlns_stanzas = "urn:ietf:params:xml:ns:xmpp-stanzas";

module "stanza"

stanza_mt = { __type = "stanza" };
stanza_mt.__index = stanza_mt;
local stanza_mt = stanza_mt;

function stanza(name, attr)
	local stanza = { name = name, attr = attr or {}, tags = {} };
	return setmetatable(stanza, stanza_mt);
end
local stanza = stanza;

function stanza_mt:query(xmlns)
	return self:tag("query", { xmlns = xmlns });
end

function stanza_mt:body(text, attr)
	return self:tag("body", attr):text(text);
end

function stanza_mt:tag(name, attrs)
	local s = stanza(name, attrs);
	local last_add = self.last_add;
	if not last_add then last_add = {}; self.last_add = last_add; end
	(last_add[#last_add] or self):add_direct_child(s);
	t_insert(last_add, s);
	return self;
end

function stanza_mt:text(text)
	local last_add = self.last_add;
	(last_add and last_add[#last_add] or self):add_direct_child(text);
	return self;
end

function stanza_mt:up()
	local last_add = self.last_add;
	if last_add then t_remove(last_add); end
	return self;
end

function stanza_mt:reset()
	self.last_add = nil;
	return self;
end

function stanza_mt:add_direct_child(child)
	if type(child) == "table" then
		t_insert(self.tags, child);
	end
	t_insert(self, child);
end

function stanza_mt:add_child(child)
	local last_add = self.last_add;
	(last_add and last_add[#last_add] or self):add_direct_child(child);
	return self;
end

function stanza_mt:get_child(name, xmlns)
	for _, child in ipairs(self.tags) do
		if (not name or child.name == name)
			and ((not xmlns and self.attr.xmlns == child.attr.xmlns)
				or child.attr.xmlns == xmlns) then
			
			return child;
		end
	end
end

function stanza_mt:get_child_text(name, xmlns)
	local tag = self:get_child(name, xmlns);
	if tag then
		return tag:get_text();
	end
	return nil;
end

function stanza_mt:child_with_name(name)
	for _, child in ipairs(self.tags) do
		if child.name == name then return child; end
	end
end

function stanza_mt:child_with_ns(ns)
	for _, child in ipairs(self.tags) do
		if child.attr.xmlns == ns then return child; end
	end
end

function stanza_mt:children()
	local i = 0;
	return function (a)
			i = i + 1
			return a[i];
		end, self, i;
end

function stanza_mt:childtags(name, xmlns)
	local tags = self.tags;
	local start_i, max_i = 1, #tags;
	return function ()
		for i = start_i, max_i do
			local v = tags[i];
			if (not name or v.name == name)
			and ((not xmlns and self.attr.xmlns == v.attr.xmlns)
				or v.attr.xmlns == xmlns) then
				start_i = i+1;
				return v;
			end
		end
	end;
end

function stanza_mt:maptags(callback)
	local tags, curr_tag = self.tags, 1;
	local n_children, n_tags = #self, #tags;
	
	local i = 1;
	while curr_tag <= n_tags and n_tags > 0 do
		if self[i] == tags[curr_tag] then
			local ret = callback(self[i]);
			if ret == nil then
				t_remove(self, i);
				t_remove(tags, curr_tag);
				n_children = n_children - 1;
				n_tags = n_tags - 1;
				i = i - 1;
				curr_tag = curr_tag - 1;
			else
				self[i] = ret;
				tags[curr_tag] = ret;
			end
			curr_tag = curr_tag + 1;
		end
		i = i + 1;
	end
	return self;
end

function stanza_mt:find(path)
	local pos = 1;
	local len = #path + 1;

	repeat
		local xmlns, name, text;
		local char = s_sub(path, pos, pos);
		if char == "@" then
			return self.attr[s_sub(path, pos + 1)];
		elseif char == "{" then
			xmlns, pos = s_match(path, "^([^}]+)}()", pos + 1);
		end
		name, text, pos = s_match(path, "^([^@/#]*)([/#]?)()", pos);
		name = name ~= "" and name or nil;
		if pos == len then
			if text == "#" then
				return self:get_child_text(name, xmlns);
			end
			return self:get_child(name, xmlns);
		end
		self = self:get_child(name, xmlns);
	until not self
end


local xml_escape
do
	local escape_table = { ["'"] = "&apos;", ["\""] = "&quot;", ["<"] = "&lt;", [">"] = "&gt;", ["&"] = "&amp;" };
	function xml_escape(str) return (s_gsub(str, "['&<>\"]", escape_table)); end
	_M.xml_escape = xml_escape;
end

local function _dostring(t, buf, self, xml_escape, parentns)
	local nsid = 0;
	local name = t.name
	t_insert(buf, "<"..name);
	for k, v in pairs(t.attr) do
		if s_find(k, "\1", 1, true) then
			local ns, attrk = s_match(k, "^([^\1]*)\1?(.*)$");
			nsid = nsid + 1;
			t_insert(buf, " xmlns:ns"..nsid.."='"..xml_escape(ns).."' ".."ns"..nsid..":"..attrk.."='"..xml_escape(v).."'");
		elseif not(k == "xmlns" and v == parentns) then
			t_insert(buf, " "..k.."='"..xml_escape(v).."'");
		end
	end
	local len = #t;
	if len == 0 then
		t_insert(buf, "/>");
	else
		t_insert(buf, ">");
		for n=1,len do
			local child = t[n];
			if child.name then
				self(child, buf, self, xml_escape, t.attr.xmlns);
			else
				t_insert(buf, xml_escape(child));
			end
		end
		t_insert(buf, "</"..name..">");
	end
end
function stanza_mt.__tostring(t)
	local buf = {};
	_dostring(t, buf, _dostring, xml_escape, nil);
	return t_concat(buf);
end

function stanza_mt.top_tag(t)
	local attr_string = "";
	if t.attr then
		for k, v in pairs(t.attr) do if type(k) == "string" then attr_string = attr_string .. s_format(" %s='%s'", k, xml_escape(tostring(v))); end end
	end
	return s_format("<%s%s>", t.name, attr_string);
end

function stanza_mt.get_text(t)
	if #t.tags == 0 then
		return t_concat(t);
	end
end

function stanza_mt.get_error(stanza)
	local type, condition, text;
	
	local error_tag = stanza:get_child("error");
	if not error_tag then
		return nil, nil, nil;
	end
	type = error_tag.attr.type;
	
	for _, child in ipairs(error_tag.tags) do
		if child.attr.xmlns == xmlns_stanzas then
			if not text and child.name == "text" then
				text = child:get_text();
			elseif not condition then
				condition = child.name;
			end
			if condition and text then
				break;
			end
		end
	end
	return type, condition or "undefined-condition", text;
end

do
	local id = 0;
	function new_id()
		id = id + 1;
		return "lx"..id;
	end
end

function preserialize(stanza)
	local s = { name = stanza.name, attr = stanza.attr };
	for _, child in ipairs(stanza) do
		if type(child) == "table" then
			t_insert(s, preserialize(child));
		else
			t_insert(s, child);
		end
	end
	return s;
end

function deserialize(stanza)
	-- Set metatable
	if stanza then
		local attr = stanza.attr;
		for i=1,#attr do attr[i] = nil; end
		local attrx = {};
		for att in pairs(attr) do
			if s_find(att, "|", 1, true) and not s_find(att, "\1", 1, true) then
				local ns,na = s_match(att, "^([^|]+)|(.+)$");
				attrx[ns.."\1"..na] = attr[att];
				attr[att] = nil;
			end
		end
		for a,v in pairs(attrx) do
			attr[a] = v;
		end
		setmetatable(stanza, stanza_mt);
		for _, child in ipairs(stanza) do
			if type(child) == "table" then
				deserialize(child);
			end
		end
		if not stanza.tags then
			-- Rebuild tags
			local tags = {};
			for _, child in ipairs(stanza) do
				if type(child) == "table" then
					t_insert(tags, child);
				end
			end
			stanza.tags = tags;
		end
	end
	
	return stanza;
end

local function _clone(stanza)
	local attr, tags = {}, {};
	for k,v in pairs(stanza.attr) do attr[k] = v; end
	local new = { name = stanza.name, attr = attr, tags = tags };
	for i=1,#stanza do
		local child = stanza[i];
		if child.name then
			child = _clone(child);
			t_insert(tags, child);
		end
		t_insert(new, child);
	end
	return setmetatable(new, stanza_mt);
end
clone = _clone;

function message(attr, body)
	if not body then
		return stanza("message", attr);
	else
		return stanza("message", attr):tag("body"):text(body):up();
	end
end
function iq(attr)
	if attr and not attr.id then attr.id = new_id(); end
	return stanza("iq", attr or { id = new_id() });
end

function reply(orig)
	return stanza(orig.name, orig.attr and { to = orig.attr.from, from = orig.attr.to, id = orig.attr.id, type = ((orig.name == "iq" and "result") or orig.attr.type) });
end

do
	local xmpp_stanzas_attr = { xmlns = xmlns_stanzas };
	function error_reply(orig, type, condition, message)
		local t = reply(orig);
		t.attr.type = "error";
		t:tag("error", {type = type}) --COMPAT: Some day xmlns:stanzas goes here
			:tag(condition, xmpp_stanzas_attr):up();
		if (message) then t:tag("text", xmpp_stanzas_attr):text(message):up(); end
		return t; -- stanza ready for adding app-specific errors
	end
end

function presence(attr)
	return stanza("presence", attr);
end

if do_pretty_printing then
	local style_attrk = getstyle("yellow");
	local style_attrv = getstyle("red");
	local style_tagname = getstyle("red");
	local style_punc = getstyle("magenta");
	
	local attr_format = " "..getstring(style_attrk, "%s")..getstring(style_punc, "=")..getstring(style_attrv, "'%s'");
	local top_tag_format = getstring(style_punc, "<")..getstring(style_tagname, "%s").."%s"..getstring(style_punc, ">");
	--local tag_format = getstring(style_punc, "<")..getstring(style_tagname, "%s").."%s"..getstring(style_punc, ">").."%s"..getstring(style_punc, "</")..getstring(style_tagname, "%s")..getstring(style_punc, ">");
	local tag_format = top_tag_format.."%s"..getstring(style_punc, "</")..getstring(style_tagname, "%s")..getstring(style_punc, ">");
	function stanza_mt.pretty_print(t)
		local children_text = "";
		for n, child in ipairs(t) do
			if type(child) == "string" then
				children_text = children_text .. xml_escape(child);
			else
				children_text = children_text .. child:pretty_print();
			end
		end

		local attr_string = "";
		if t.attr then
			for k, v in pairs(t.attr) do if type(k) == "string" then attr_string = attr_string .. s_format(attr_format, k, tostring(v)); end end
		end
		return s_format(tag_format, t.name, attr_string, children_text, t.name);
	end
	
	function stanza_mt.pretty_top_tag(t)
		local attr_string = "";
		if t.attr then
			for k, v in pairs(t.attr) do if type(k) == "string" then attr_string = attr_string .. s_format(attr_format, k, tostring(v)); end end
		end
		return s_format(top_tag_format, t.name, attr_string);
	end
else
	-- Sorry, fresh out of colours for you guys ;)
	stanza_mt.pretty_print = stanza_mt.__tostring;
	stanza_mt.pretty_top_tag = stanza_mt.top_tag;
end

return _M;