view mod_http_prebind/mod_http_prebind.lua @ 5461:06640647d193

mod_http_oauth2: Fix use of arbitrary ports in loopback redirect URIs Per draft-ietf-oauth-v2-1-08#section-8.4.2 > The authorization server MUST allow any port to be specified at the > time of the request for loopback IP redirect URIs, to accommodate > clients that obtain an available ephemeral port from the operating > system at the time of the request. Uncertain if it should normalize the host part, but it also seems harmless to treat IPv6 and IPv4 the same here. One thing is that "localhost" is NOT RECOMMENDED because it can sometimes be pointed to non-loopback interfaces via DNS or hosts file.
author Kim Alvefur <zash@zash.se>
date Wed, 17 May 2023 13:51:30 +0200
parents 495a23d61418
children
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module:depends("http");

local http = require "net.http";
local format = require "util.format".format;
local json_encode = require "util.json".encode;
local promise = require "util.promise";
local xml = require "util.xml";
local t_insert = table.insert;

local function new_options(host)
	return {
		headers = {
			["Content-Type"] = "text/xml; charset=utf-8",
			["Host"] = host,
		},
		method = "POST",
	};
end

local function connect_to_bosh(url, hostname)
	local rid = math.random(100000, 100000000)
	local options = new_options(hostname);
	options.body = format([[<body content='text/xml; charset=utf-8'
	      hold='1'
	      rid='%d'
	      to='%s'
	      wait='60'
	      xml:lang='en'
	      xmpp:version='1.0'
	      xmlns='http://jabber.org/protocol/httpbind'
	      xmlns:xmpp='urn:xmpp:xbosh'/>]], rid, hostname);
	local rid = rid + 1;
	return promise.new(function (on_fulfilled, on_error)
		assert(http.request(url, options, function (body, code)
			if code ~= 200 then
				on_error("Failed to fetch, HTTP error code "..code);
				return;
			end
			local body = xml.parse(body);
			local sid = body.attr.sid;
			local mechanisms = {};
			for mechanism in body:get_child("features", "http://etherx.jabber.org/streams")
				:get_child("mechanisms", "urn:ietf:params:xml:ns:xmpp-sasl")
					:childtags("mechanism", "urn:ietf:params:xml:ns:xmpp-sasl") do
				mechanisms[mechanism:get_text()] = true;
			end
			on_fulfilled({ url = url, sid = sid, rid = rid, mechanisms = mechanisms });
		end));
	end);
end

local function authenticate(data)
	local options = new_options();
	options.body = format([[<body sid='%s'
	      rid='%d'
	      xmlns='http://jabber.org/protocol/httpbind'>
		<auth xmlns='urn:ietf:params:xml:ns:xmpp-sasl'
		      mechanism='ANONYMOUS'/>
	</body>]], data.sid, data.rid);
	data.rid = data.rid + 1;
	return promise.new(function (on_fulfilled, on_error)
		if data.mechanisms["ANONYMOUS"] == nil then
			on_error("No SASL ANONYMOUS mechanism supported on this host.");
			return;
		end
		assert(http.request(data.url, options, function (body, code)
			if code ~= 200 then
				on_error("Failed to fetch, HTTP error code "..code);
				return;
			end
			local body = xml.parse(body);
			local success = body:get_child("success", "urn:ietf:params:xml:ns:xmpp-sasl");
			if success then
				data.mechanisms = nil;
				on_fulfilled(data);
			else
				on_error("Authentication failed.");
			end
		end));
	end);
end;

local function restart_stream(data)
	local options = new_options();
	options.body = format([[
	<body sid='%s'
	      rid='%d'
	      xml:lang='en'
	      xmlns='http://jabber.org/protocol/httpbind'
	      xmlns:xmpp='urn:xmpp:xbosh'
	      xmpp:restart='true'/>]], data.sid, data.rid);
	data.rid = data.rid + 1;
	return promise.new(function (on_fulfilled, on_error)
		assert(http.request(data.url, options, function (body, code)
			if code ~= 200 then
				on_error("Failed to fetch, HTTP error code "..code);
				return;
			end
			local body = xml.parse(body);
			on_fulfilled(data);
		end));
	end);
end;

local function bind(data)
	local options = new_options();
	options.body = format([[
	<body sid='%s'
	      rid='%d'
	      xmlns='http://jabber.org/protocol/httpbind'>
		<iq xmlns='jabber:client'
		    type='set'>
			<bind xmlns='urn:ietf:params:xml:ns:xmpp-bind'/>
		</iq>
	</body>]], data.sid, data.rid);
	data.rid = data.rid + 1;
	return promise.new(function (on_fulfilled, on_error)
		assert(http.request(data.url, options, function (body, code)
			if code ~= 200 then
				on_error("Failed to fetch, HTTP error code "..code);
				return;
			end
			local body = xml.parse(body);
			local jid = body:get_child("iq", "jabber:client")
				:get_child("bind", "urn:ietf:params:xml:ns:xmpp-bind")
					:get_child_text("jid", "urn:ietf:params:xml:ns:xmpp-bind");
			on_fulfilled(json_encode({rid = data.rid, sid = data.sid, jid = jid}));
		end));
	end);
end;

module:provides("http", {
	route = {
		["GET"] = function (event)
			return connect_to_bosh("http://[::1]:5280/http-bind", module.host)
				:next(authenticate)
				:next(restart_stream)
				:next(bind);
		end;
	};
});