--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_auth_joomla/mod_auth_joomla.lua	Sun Sep 11 23:58:20 2011 +0500
@@ -0,0 +1,180 @@
+-- Joomla authentication backend for Prosody
+--
+-- Copyright (C) 2011 Waqas Hussain
+--
+
+local new_sasl = require "util.sasl".new;
+local nodeprep = require "util.encodings".stringprep.nodeprep;
+local saslprep = require "util.encodings".stringprep.saslprep;
+local DBI = require "DBI"
+local md5 = require "util.hashes".md5;
+local uuid_gen = require "util.uuid".generate;
+
+local connection;
+local params = module:get_option("sql");
+
+local resolve_relative_path = require "core.configmanager".resolve_relative_path;
+
+local function test_connection()
+	if not connection then return nil; end
+	if connection:ping() then
+		return true;
+	else
+		module:log("debug", "Database connection closed");
+		connection = nil;
+	end
+end
+local function connect()
+	if not test_connection() then
+		prosody.unlock_globals();
+		local dbh, err = DBI.Connect(
+			params.driver, params.database,
+			params.username, params.password,
+			params.host, params.port
+		);
+		prosody.lock_globals();
+		if not dbh then
+			module:log("debug", "Database connection failed: %s", tostring(err));
+			return nil, err;
+		end
+		module:log("debug", "Successfully connected to database");
+		dbh:autocommit(true); -- don't run in transaction
+		connection = dbh;
+		return connection;
+	end
+end
+
+do -- process options to get a db connection
+	params = params or { driver = "SQLite3" };
+	
+	if params.driver == "SQLite3" then
+		params.database = resolve_relative_path(prosody.paths.data or ".", params.database or "prosody.sqlite");
+	end
+	
+	assert(params.driver and params.database, "Both the SQL driver and the database need to be specified");
+	
+	assert(connect());
+end
+
+local function getsql(sql, ...)
+	if params.driver == "PostgreSQL" then
+		sql = sql:gsub("`", "\"");
+	end
+	if not test_connection() then connect(); end
+	-- do prepared statement stuff
+	local stmt, err = connection:prepare(sql);
+	if not stmt and not test_connection() then error("connection failed"); end
+	if not stmt then module:log("error", "QUERY FAILED: %s %s", err, debug.traceback()); return nil, err; end
+	-- run query
+	local ok, err = stmt:execute(...);
+	if not ok and not test_connection() then error("connection failed"); end
+	if not ok then return nil, err; end
+	
+	return stmt;
+end
+local function setsql(sql, ...)
+	local stmt, err = getsql(sql, ...);
+	if not stmt then return stmt, err; end
+	return stmt:affected();
+end
+
+local function get_password(username)
+	local stmt, err = getsql("SELECT `password` FROM `jos_users` WHERE `username`=?", username);
+	if stmt then
+		for row in stmt:rows(true) do
+			return row.password;
+		end
+	end
+end
+
+
+local function getCryptedPassword(plaintext, salt)
+	return md5(plaintext..salt);
+end
+local function joomlaCheckHash(password, hash)
+	local crypt, salt = hash:match("^([^:]*):(.*)$");
+	return (crypt or hash) == getCryptedPassword(password, salt or '');
+end
+local function joomlaCreateHash(password)
+	local salt = uuid_gen():gsub("%-", "");
+	local crypt = getCryptedPassword(password, salt);
+	return crypt..':'..salt;
+end
+
+
+provider = { name = "joomla" };
+
+function provider.test_password(username, password)
+	local hash = get_password(username);
+	return hash and joomlaCheckHash(password, hash);
+end
+function provider.user_exists(username)
+	module:log("debug", "test user %s existence", username);
+	return get_password(username) and true;
+end
+
+function provider.get_password(username)
+	return nil, "Getting password is not supported.";
+end
+function provider.set_password(username, password)
+	local hash = joomlaCreateHash(password);
+	local stmt, err = setsql("UPDATE `jos_users` SET `password`=? WHERE `username`=?", hash, username);
+	return stmt and true, err;
+end
+function provider.create_user(username, password)
+	return nil, "Account creation/modification not supported.";
+end
+
+local escapes = {
+	[" "] = "\\20";
+	['"'] = "\\22";
+	["&"] = "\\26";
+	["'"] = "\\27";
+	["/"] = "\\2f";
+	[":"] = "\\3a";
+	["<"] = "\\3c";
+	[">"] = "\\3e";
+	["@"] = "\\40";
+	["\\"] = "\\5c";
+};
+local unescapes = {};
+for k,v in pairs(escapes) do unescapes[v] = k; end
+local function jid_escape(s) return s and (s:gsub(".", escapes)); end
+local function jid_unescape(s) return s and (s:gsub("\\%x%x", unescapes)); end
+
+function provider.get_sasl_handler()
+	local sasl = {};
+	function sasl:clean_clone() return provider.get_sasl_handler(); end
+	function sasl:mechanisms() return { PLAIN = true; }; end
+	function sasl:select(mechanism)
+		if not self.selected and mechanism == "PLAIN" then
+			self.selected = mechanism;
+			return true;
+		end
+	end
+	function sasl:process(message)
+		if not message then return "failure", "malformed-request"; end
+		local authorization, authentication, password = message:match("^([^%z]*)%z([^%z]+)%z([^%z]+)");
+		if not authorization then return "failure", "malformed-request"; end
+		authentication = saslprep(authentication);
+		password = saslprep(password);
+		if (not password) or (password == "") or (not authentication) or (authentication == "") then
+			return "failure", "malformed-request", "Invalid username or password.";
+		end
+		local function test(authentication)
+			local prepped = nodeprep(authentication);
+			local normalized = jid_unescape(prepped);
+			return normalized and provider.test_password(normalized, password) and prepped;
+		end
+		local username = test(authentication) or test(jid_escape(authentication));
+		if username then
+			self.username = username;
+			return "success";
+		end
+		return "failure", "not-authorized", "Unable to authorize you with the authentication credentials you've sent.";
+	end
+	return sasl;
+end
+
+module:add_item("auth-provider", provider);
+