--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_register_json/register_json/mod_register_json.lua	Mon Apr 29 22:53:39 2013 +0200
@@ -0,0 +1,279 @@
+-- Expose a simple token based servlet to handle user registrations from web pages
+-- through Base64 encoded JSON.
+
+-- Copyright (C) 2010 - 2013, Marco Cirillo (LW.Org)
+
+local datamanager = datamanager
+local b64_decode = require "util.encodings".base64.decode
+local b64_encode = require "util.encodings".base64.encode
+local http_event = require "net.http.server".fire_event
+local jid_prep = require "util.jid".prep
+local jid_split = require "util.jid".split
+local json_decode = require "util.json".decode
+local nodeprep = require "util.encodings".stringprep.nodeprep
+local open, os_time, setmt, type = io.open, os.time, setmetatable, type
+local sha1 = require "util.hashes".sha1
+local urldecode = http.urldecode
+local usermanager = usermanager
+local uuid_gen = require "util.uuid".generate
+local timer = require "util.timer"
+
+module:depends("http")
+
+-- Pick up configuration and setup stores/variables.
+
+local auth_token = module:get_option_string("reg_servlet_auth_token")
+local secure = module:get_option_boolean("reg_servlet_secure", true)
+local base_path = module:get_option_string("reg_servlet_base", "/register_account/")
+local throttle_time = module:get_option_number("reg_servlet_ttime", nil)
+local whitelist = module:get_option_set("reg_servlet_wl", {})
+local blacklist = module:get_option_set("reg_servlet_bl", {})
+local fm_patterns = module:get_option("reg_servlet_filtered_mails", {})
+if type(fm_patterns) ~= "table" then fm_patterns = {} end
+
+local files_base = module.path:gsub("/[^/]+$","") .. "/template/"
+
+local recent_ips = {}
+local pending = {}
+local pending_node = {}
+
+-- Setup hashes data structure
+
+hashes = { _index = {} }
+local hashes_mt = {} ; hashes_mt.__index = hashes_mt
+function hashes_mt:add(node, mail)
+	local _hash = b64_encode(sha1(mail))
+	if not self:exists(_hash) then
+		self[_hash] = node ; self._index[node] = _hash ; self:save()
+		return true
+	else
+		return false
+	end
+end
+function hashes_mt:exists(hash)
+	if hashes[hash] then return true else return false end
+end
+function hashes_mt:remove(node)
+	local _hash = self._index[node]
+	if _hash then
+		self[_hash] = nil ; self._index[node] = nil ; self:save()
+	end
+end
+function hashes_mt:save()
+	if not datamanager.store("register_json", module.host, "hashes", hashes) then
+		module:log("error", "Failed to save the mail addresses' hashes store.")
+	end
+end
+
+local function check_mail(address)
+	for _, pattern in ipairs(fm_patterns) do 
+		if address:match(pattern) then return false end
+	end
+	return true
+end
+
+-- Begin
+
+local function handle(code, message) return http_event("http-error", { code = code, message = message }) end
+local function http_response(event, code, message, headers)
+	local response = event.response
+
+	if headers then
+		for header, data in pairs(headers) do response.headers[header] = data end
+	end
+
+	response.status_code = code
+	response:send(handle(code, message))
+end
+
+local function handle_req(event)
+	local response = event.response
+	local request = event.request
+	local body = request.body
+	if secure and not request.secure then return nil end
+
+	if request.method ~= "POST" then
+		return http_response(event, 405, "Bad method.", {["Allow"] = "POST"})
+	end
+	
+	local req_body
+	-- We check that what we have is valid JSON wise else we throw an error...
+	if not pcall(function() req_body = json_decode(b64_decode(body)) end) then
+		module:log("debug", "Data submitted for user registration by %s failed to Decode.", user)
+		return http_response(event, 400, "Decoding failed.")
+	else
+		-- Decode JSON data and check that all bits are there else throw an error
+		if req_body["username"] == nil or req_body["password"] == nil or req_body["ip"] == nil or req_body["mail"] == nil or
+		   req_body["auth_token"] == nil then
+			module:log("debug", "%s supplied an insufficent number of elements or wrong elements for the JSON registration", user)
+			return http_response(event, 400, "Invalid syntax.")
+		end
+		-- Set up variables
+		local username, password, ip, mail, token = req_body.username, req_body.password, req_body.ip, req_body.mail, req_body.auth_token
+
+		-- Check if user is an admin of said host
+		if token ~= auth_token then
+			module:log("warn", "%s tried to retrieve a registration token for %s@%s", request.ip, username, module.host)
+			return http_response(event, 401, "Auth token is invalid! The attempt has been logged.")
+		else	
+			-- Blacklist can be checked here.
+			if blacklist:contains(ip) then 
+				module:log("warn", "Attempt of reg. submission to the JSON servlet from blacklisted address: %s", ip)
+				return http_response(403, "The specified address is blacklisted, sorry.") 
+			end
+
+			if not check_mail(mail) then
+				module:log("warn", "%s attempted to use a mail address (%s) matching one of the forbidden patterns.", ip, mail)
+				return http_response(403, "Requesting to register using this E-Mail address is forbidden, sorry.")
+			end
+
+			-- We first check if the supplied username for registration is already there.
+			-- And nodeprep the username
+			username = nodeprep(username)
+			if not username then
+				module:log("debug", "An username containing invalid characters was supplied: %s", req_body["username"])
+				return http_response(event, 406, "Supplied username contains invalid characters, see RFC 6122.")
+			else
+				if pending_node[username] then
+					module:log("warn", "%s attempted to submit a registration request but another request for that user is pending")
+					return http_response(event, 401, "Another user registration by that username is pending.")
+				end
+
+				if not usermanager.user_exists(username, module.host) then
+					-- if username fails to register successive requests shouldn't be throttled until one is successful.
+					if throttle_time and not whitelist:contains(ip) then
+						if not recent_ips[ip] then
+							recent_ips[ip] = os_time()
+						else 
+							if os_time() - recent_ips[ip] < throttle_time then
+								recent_ips[ip] = os_time()
+								module:log("warn", "JSON Registration request from %s has been throttled.", req_body["ip"])
+								return http_response(event, 503, "Request throttled, wait a bit and try again.")
+							end
+							recent_ips[ip] = os_time()
+						end
+					end
+
+					local uuid = uuid_gen()
+					if not hashes:add(username, mail) then
+						module:log("warn", "%s (%s) attempted to register to the server with an E-Mail address we already possess the hash of.", username, ip)
+						return http_response(event, 409, "The E-Mail Address provided matches the hash associated to an existing account.")
+					end
+					pending[uuid] = { node = username, password = password, ip = ip }
+					pending_node[username] = uuid
+
+					timer.add_task(300, function()
+						if pending[uuid] then
+							pending[uuid] = nil
+							pending_node[username] = nil
+							hashes:remove(username)
+						end
+					end)
+					module:log("info", "%s (%s) submitted a registration request and is awaiting final verification", username, uuid)
+					return uuid
+				else
+					module:log("debug", "%s registration data submission failed (user already exists)", username)
+					return http_response(event, 409, "User already exists.")
+				end
+			end
+		end
+	end
+end
+
+local function open_file(file)
+	local f, err = open(file, "rb");
+	if not f then return nil end
+
+	local data = f:read("*a") ; f:close()
+	return data
+end
+
+local function r_template(event, type)
+	local response = event.response
+
+	local data = open_file(files_base..type.."_t.html")
+	if data then
+		data = data:gsub("%%REG%-URL", base_path.."verify/")
+		return data
+	else return http_response(event, 500, "Failed to obtain template.") end
+end
+
+local function handle_verify(event, path)
+	local response = event.response
+	local request = event.request
+	local body = request.body
+	if secure and not request.secure then return nil end
+
+	local valid_files = {
+		["css/style.css"] = files_base.."css/style.css",
+		["images/tile.png"] = files_base.."images/tile.png",
+		["images/header.png"] = files_base.."images/header.png"
+	}
+
+	if request.method == "GET" then
+		if path == "" then
+			return r_template(event, "form")
+		end		
+
+		if valid_files[path] then
+			local data = open_file(valid_files[path])
+			if data then return data
+			else return http_response(event, 404, "Not found.") end
+		end
+	elseif request.method == "POST" then
+		if path == "" then
+			if not request.body then return http_response(event, 400, "Bad Request.") end
+			local uuid = urldecode(request.body):match("^uuid=(.*)$")
+
+			if not pending[uuid] then
+				return r_template(event, "fail")
+			else
+				local username, password, ip = 
+				      pending[uuid].node, pending[uuid].password, pending[uuid].ip
+
+				local ok, error = usermanager.create_user(username, password, module.host)
+				if ok then 
+					module:fire_event(
+						"user-registered", 
+						{ username = username, host = module.host, source = "mod_register_json", session = { ip = ip } }
+					)
+					module:log("info", "Account %s@%s is successfully verified and activated", username, module.host)
+					-- we shall not clean the user from the pending lists as long as registration doesn't succeed.
+					pending[uuid] = nil ; pending_node[username] = nil
+					return r_template(event, "success")				
+				else
+					module:log("error", "User creation failed: "..error)
+					return http_response(event, 500, "Encountered server error while creating the user: "..error)
+				end
+			end
+		end	
+	else
+		return http_response(event, 405, "Invalid method.")
+	end
+end
+
+local function handle_user_deletion(event)
+	local user, hostname = event.username, event.host
+	if hostname == module.host then hashes:remove(user) end
+end
+
+-- Set it up!
+
+hashes = datamanager.load("register_json", module.host, "hashes") or hashes ; setmt(hashes, hashes_mt)
+
+module:provides("http", {
+	default_path = base_path,
+        route = {
+                ["GET /"] = handle_req,
+		["POST /"] = handle_req,
+		["GET /verify/*"] = handle_verify,
+		["POST /verify/*"] = handle_verify
+        }
+})
+
+module:hook_global("user-deleted", handle_user_deletion, 10);
+
+-- Reloadability
+
+module.save = function() return { hashes = hashes } end
+module.restore = function(data) hashes = data.hashes or { _index = {} } ; setmt(hashes, hashes_mt) end