File

plugins/mod_admin_telnet.lua @ 10067:598befab492e

mod_admin_telnet: Check for simple commands before executing in sandbox This makes fixing yield over pcall boundry issue easier since it would have jumped to the thread error handler instead of proceeding to checking for simple commands.
author Kim Alvefur <zash@zash.se>
date Fri, 10 May 2019 01:28:09 +0200
parent 10044:4fd27023224a
child 10068:73a8192058f9
line wrap: on
line source

-- 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.
--
-- luacheck: ignore 212/self

module:set_global();

local hostmanager = require "core.hostmanager";
local modulemanager = require "core.modulemanager";
local s2smanager = require "core.s2smanager";
local portmanager = require "core.portmanager";
local helpers = require "util.helpers";
local server = require "net.server";

local _G = _G;

local prosody = _G.prosody;

local console_listener = { default_port = 5582; default_mode = "*a"; interface = "127.0.0.1" };

local unpack = table.unpack or unpack; -- luacheck: ignore 113
local iterators = require "util.iterators";
local keys, values = iterators.keys, iterators.values;
local jid_bare, jid_split, jid_join = import("util.jid", "bare", "prepped_split", "join");
local set, array = require "util.set", require "util.array";
local cert_verify_identity = require "util.x509".verify_identity;
local envload = require "util.envload".envload;
local envloadfile = require "util.envload".envloadfile;
local has_pposix, pposix = pcall(require, "util.pposix");
local async = require "util.async";
local serialize = require "util.serialization".new({ fatal = false, unquoted = true});

local commands = module:shared("commands")
local def_env = module:shared("env");
local default_env_mt = { __index = def_env };

local function redirect_output(target, session)
	local env = setmetatable({ print = session.print }, { __index = function (_, k) return rawget(target, k); end });
	env.dofile = function(name)
		local f, err = envloadfile(name, env);
		if not f then return f, err; end
		return f();
	end;
	return env;
end

console = {};

local runner_callbacks = {};

function runner_callbacks:ready()
	self.data.conn:resume();
end

function runner_callbacks:waiting()
	self.data.conn:pause();
end

function runner_callbacks:error(err)
	module:log("error", "Traceback[telnet]: %s", err);
end


function console:new_session(conn)
	local w = function(s) conn:write(s:gsub("\n", "\r\n")); end;
	local session = { conn = conn;
			send = function (t) w(tostring(t)); end;
			print = function (...)
				local t = {};
				for i=1,select("#", ...) do
					t[i] = tostring(select(i, ...));
				end
				w("| "..table.concat(t, "\t").."\n");
			end;
			disconnect = function () conn:close(); end;
			};
	session.env = setmetatable({}, default_env_mt);

	session.thread = async.runner(function (line)
		console:process_line(session, line);
		session.send(string.char(0));
	end, runner_callbacks, session);

	-- Load up environment with helper objects
	for name, t in pairs(def_env) do
		if type(t) == "table" then
			session.env[name] = setmetatable({ session = session }, { __index = t });
		end
	end

	return session;
end

function console:process_line(session, line)
	local useglobalenv;

	if line:match("^>") then
		line = line:gsub("^>", "");
		useglobalenv = true;
	elseif line == "\004" then
		commands["bye"](session, line);
		return;
	else
		local command = line:match("^%w+") or line:match("%p");
		if commands[command] then
			commands[command](session, line);
			return;
		end
	end

	session.env._ = line;

	if not useglobalenv and commands[line:lower()] then
		commands[line:lower()](session, line);
		return;
	end

	local chunkname = "=console";
	local env = (useglobalenv and redirect_output(_G, session)) or session.env or nil
	local chunk, err = envload("return "..line, chunkname, env);
	if not chunk then
		chunk, err = envload(line, chunkname, env);
		if not chunk then
			err = err:gsub("^%[string .-%]:%d+: ", "");
			err = err:gsub("^:%d+: ", "");
			err = err:gsub("'<eof>'", "the end of the line");
			session.print("Sorry, I couldn't understand that... "..err);
			return;
		end
	end

	local ranok, taskok, message = pcall(chunk);

	if not ranok then
		session.print("Fatal error while running command, it did not complete");
		session.print("Error: "..taskok);
		return;
	end

	if not message then
		session.print("Result: "..tostring(taskok));
		return;
	elseif (not taskok) and message then
		session.print("Command completed with a problem");
		session.print("Message: "..tostring(message));
		return;
	end

	session.print("OK: "..tostring(message));
end

local sessions = {};

function console_listener.onconnect(conn)
	-- Handle new connection
	local session = console:new_session(conn);
	sessions[conn] = session;
	printbanner(session);
	session.send(string.char(0));
end

function console_listener.onincoming(conn, data)
	local session = sessions[conn];

	local partial = session.partial_data;
	if partial then
		data = partial..data;
	end

	for line in data:gmatch("[^\n]*[\n\004]") do
		if session.closed then return end
		session.thread:run(line);
	end
	session.partial_data = data:match("[^\n]+$");
end

function console_listener.onreadtimeout(conn)
	local session = sessions[conn];
	if session then
		session.send("\0");
		return true;
	end
end

function console_listener.ondisconnect(conn, err) -- luacheck: ignore 212/err
	local session = sessions[conn];
	if session then
		session.disconnect();
		sessions[conn] = nil;
	end
end

function console_listener.ondetach(conn)
	sessions[conn] = nil;
end

-- Console commands --
-- These are simple commands, not valid standalone in Lua

function commands.bye(session)
	session.print("See you! :)");
	session.closed = true;
	session.disconnect();
end
commands.quit, commands.exit = commands.bye, commands.bye;

commands["!"] = function (session, data)
	if data:match("^!!") and session.env._ then
		session.print("!> "..session.env._);
		return console_listener.onincoming(session.conn, session.env._);
	end
	local old, new = data:match("^!(.-[^\\])!(.-)!$");
	if old and new then
		local ok, res = pcall(string.gsub, session.env._, old, new);
		if not ok then
			session.print(res)
			return;
		end
		session.print("!> "..res);
		return console_listener.onincoming(session.conn, res);
	end
	session.print("Sorry, not sure what you want");
end


function commands.help(session, data)
	local print = session.print;
	local section = data:match("^help (%w+)");
	if not section then
		print [[Commands are divided into multiple sections. For help on a particular section, ]]
		print [[type: help SECTION (for example, 'help c2s'). Sections are: ]]
		print [[]]
		print [[c2s - Commands to manage local client-to-server sessions]]
		print [[s2s - Commands to manage sessions between this server and others]]
		print [[module - Commands to load/reload/unload modules/plugins]]
		print [[host - Commands to activate, deactivate and list virtual hosts]]
		print [[user - Commands to create and delete users, and change their passwords]]
		print [[server - Uptime, version, shutting down, etc.]]
		print [[port - Commands to manage ports the server is listening on]]
		print [[dns - Commands to manage and inspect the internal DNS resolver]]
		print [[config - Reloading the configuration, etc.]]
		print [[console - Help regarding the console itself]]
	elseif section == "c2s" then
		print [[c2s:show(jid) - Show all client sessions with the specified JID (or all if no JID given)]]
		print [[c2s:show_insecure() - Show all unencrypted client connections]]
		print [[c2s:show_secure() - Show all encrypted client connections]]
		print [[c2s:show_tls() - Show TLS cipher info for encrypted sessions]]
		print [[c2s:close(jid) - Close all sessions for the specified JID]]
		print [[c2s:closeall() - Close all active c2s connections ]]
	elseif section == "s2s" then
		print [[s2s:show(domain) - Show all s2s connections for the given domain (or all if no domain given)]]
		print [[s2s:show_tls(domain) - Show TLS cipher info for encrypted sessions]]
		print [[s2s:close(from, to) - Close a connection from one domain to another]]
		print [[s2s:closeall(host) - Close all the incoming/outgoing s2s sessions to specified host]]
	elseif section == "module" then
		print [[module:load(module, host) - Load the specified module on the specified host (or all hosts if none given)]]
		print [[module:reload(module, host) - The same, but unloads and loads the module (saving state if the module supports it)]]
		print [[module:unload(module, host) - The same, but just unloads the module from memory]]
		print [[module:list(host) - List the modules loaded on the specified host]]
	elseif section == "host" then
		print [[host:activate(hostname) - Activates the specified host]]
		print [[host:deactivate(hostname) - Disconnects all clients on this host and deactivates]]
		print [[host:list() - List the currently-activated hosts]]
	elseif section == "user" then
		print [[user:create(jid, password) - Create the specified user account]]
		print [[user:password(jid, password) - Set the password for the specified user account]]
		print [[user:delete(jid) - Permanently remove the specified user account]]
		print [[user:list(hostname, pattern) - List users on the specified host, optionally filtering with a pattern]]
	elseif section == "server" then
		print [[server:version() - Show the server's version number]]
		print [[server:uptime() - Show how long the server has been running]]
		print [[server:memory() - Show details about the server's memory usage]]
		print [[server:shutdown(reason) - Shut down the server, with an optional reason to be broadcast to all connections]]
	elseif section == "port" then
		print [[port:list() - Lists all network ports prosody currently listens on]]
		print [[port:close(port, interface) - Close a port]]
	elseif section == "dns" then
		print [[dns:lookup(name, type, class) - Do a DNS lookup]]
		print [[dns:addnameserver(nameserver) - Add a nameserver to the list]]
		print [[dns:setnameserver(nameserver) - Replace the list of name servers with the supplied one]]
		print [[dns:purge() - Clear the DNS cache]]
		print [[dns:cache() - Show cached records]]
	elseif section == "config" then
		print [[config:reload() - Reload the server configuration. Modules may need to be reloaded for changes to take effect.]]
	elseif section == "console" then
		print [[Hey! Welcome to Prosody's admin console.]]
		print [[First thing, if you're ever wondering how to get out, simply type 'quit'.]]
		print [[Secondly, note that we don't support the full telnet protocol yet (it's coming)]]
		print [[so you may have trouble using the arrow keys, etc. depending on your system.]]
		print [[]]
		print [[For now we offer a couple of handy shortcuts:]]
		print [[!! - Repeat the last command]]
		print [[!old!new! - repeat the last command, but with 'old' replaced by 'new']]
		print [[]]
		print [[For those well-versed in Prosody's internals, or taking instruction from those who are,]]
		print [[you can prefix a command with > to escape the console sandbox, and access everything in]]
		print [[the running server. Great fun, but be careful not to break anything :)]]
	end
	print [[]]
end

-- Session environment --
-- Anything in def_env will be accessible within the session as a global variable

--luacheck: ignore 212/self

def_env.server = {};

function def_env.server:insane_reload()
	prosody.unlock_globals();
	dofile "prosody"
	prosody = _G.prosody;
	return true, "Server reloaded";
end

function def_env.server:version()
	return true, tostring(prosody.version or "unknown");
end

function def_env.server:uptime()
	local t = os.time()-prosody.start_time;
	local seconds = t%60;
	t = (t - seconds)/60;
	local minutes = t%60;
	t = (t - minutes)/60;
	local hours = t%24;
	t = (t - hours)/24;
	local days = t;
	return true, string.format("This server has been running for %d day%s, %d hour%s and %d minute%s (since %s)",
		days, (days ~= 1 and "s") or "", hours, (hours ~= 1 and "s") or "",
		minutes, (minutes ~= 1 and "s") or "", os.date("%c", prosody.start_time));
end

function def_env.server:shutdown(reason)
	prosody.shutdown(reason);
	return true, "Shutdown initiated";
end

local function human(kb)
	local unit = "K";
	if kb > 1024 then
		kb, unit = kb/1024, "M";
	end
	return ("%0.2f%sB"):format(kb, unit);
end

function def_env.server:memory()
	if not has_pposix or not pposix.meminfo then
		return true, "Lua is using "..human(collectgarbage("count"));
	end
	local mem, lua_mem = pposix.meminfo(), collectgarbage("count");
	local print = self.session.print;
	print("Process: "..human((mem.allocated+mem.allocated_mmap)/1024));
	print("   Used: "..human(mem.used/1024).." ("..human(lua_mem).." by Lua)");
	print("   Free: "..human(mem.unused/1024).." ("..human(mem.returnable/1024).." returnable)");
	return true, "OK";
end

def_env.module = {};

local function get_hosts_set(hosts, module)
	if type(hosts) == "table" then
		if hosts[1] then
			return set.new(hosts);
		elseif hosts._items then
			return hosts;
		end
	elseif type(hosts) == "string" then
		return set.new { hosts };
	elseif hosts == nil then
		local hosts_set = set.new(array.collect(keys(prosody.hosts)))
			/ function (host) return (prosody.hosts[host].type == "local" or module and modulemanager.is_loaded(host, module)) and host or nil; end;
		if module and modulemanager.get_module("*", module) then
			hosts_set:add("*");
		end
		return hosts_set;
	end
end

function def_env.module:load(name, hosts, config)
	hosts = get_hosts_set(hosts);

	-- Load the module for each host
	local ok, err, count, mod = true, nil, 0;
	for host in hosts do
		if (not modulemanager.is_loaded(host, name)) then
			mod, err = modulemanager.load(host, name, config);
			if not mod then
				ok = false;
				if err == "global-module-already-loaded" then
					if count > 0 then
						ok, err, count = true, nil, 1;
					end
					break;
				end
				self.session.print(err or "Unknown error loading module");
			else
				count = count + 1;
				self.session.print("Loaded for "..mod.module.host);
			end
		end
	end

	return ok, (ok and "Module loaded onto "..count.." host"..(count ~= 1 and "s" or "")) or ("Last error: "..tostring(err));
end

function def_env.module:unload(name, hosts)
	hosts = get_hosts_set(hosts, name);

	-- Unload the module for each host
	local ok, err, count = true, nil, 0;
	for host in hosts do
		if modulemanager.is_loaded(host, name) then
			ok, err = modulemanager.unload(host, name);
			if not ok then
				ok = false;
				self.session.print(err or "Unknown error unloading module");
			else
				count = count + 1;
				self.session.print("Unloaded from "..host);
			end
		end
	end
	return ok, (ok and "Module unloaded from "..count.." host"..(count ~= 1 and "s" or "")) or ("Last error: "..tostring(err));
end

local function _sort_hosts(a, b)
	if a == "*" then return true
	elseif b == "*" then return false
	else return a < b; end
end

function def_env.module:reload(name, hosts)
	hosts = array.collect(get_hosts_set(hosts, name)):sort(_sort_hosts)

	-- Reload the module for each host
	local ok, err, count = true, nil, 0;
	for _, host in ipairs(hosts) do
		if modulemanager.is_loaded(host, name) then
			ok, err = modulemanager.reload(host, name);
			if not ok then
				ok = false;
				self.session.print(err or "Unknown error reloading module");
			else
				count = count + 1;
				if ok == nil then
					ok = true;
				end
				self.session.print("Reloaded on "..host);
			end
		end
	end
	return ok, (ok and "Module reloaded on "..count.." host"..(count ~= 1 and "s" or "")) or ("Last error: "..tostring(err));
end

function def_env.module:list(hosts)
	if hosts == nil then
		hosts = array.collect(keys(prosody.hosts));
		table.insert(hosts, 1, "*");
	end
	if type(hosts) == "string" then
		hosts = { hosts };
	end
	if type(hosts) ~= "table" then
		return false, "Please supply a host or a list of hosts you would like to see";
	end

	local print = self.session.print;
	for _, host in ipairs(hosts) do
		print((host == "*" and "Global" or host)..":");
		local modules = array.collect(keys(modulemanager.get_modules(host) or {})):sort();
		if #modules == 0 then
			if prosody.hosts[host] then
				print("    No modules loaded");
			else
				print("    Host not found");
			end
		else
			for _, name in ipairs(modules) do
				local status, status_text = modulemanager.get_module(host, name).module:get_status();
				local status_summary = "";
				if status == "warn" or status == "error" then
					status_summary = (" (%s: %s)"):format(status, status_text);
				end
				print(("    %s%s"):format(name, status_summary));
			end
		end
	end
end

def_env.config = {};
function def_env.config:load(filename, format)
	local config_load = require "core.configmanager".load;
	local ok, err = config_load(filename, format);
	if not ok then
		return false, err or "Unknown error loading config";
	end
	return true, "Config loaded";
end

function def_env.config:get(host, key)
	if key == nil then
		host, key = "*", host;
	end
	local config_get = require "core.configmanager".get
	return true, serialize(config_get(host, key));
end

function def_env.config:reload()
	local ok, err = prosody.reload_config();
	return ok, (ok and "Config reloaded (you may need to reload modules to take effect)") or tostring(err);
end

local function common_info(session, line)
	if session.id then
		line[#line+1] = "["..session.id.."]"
	else
		line[#line+1] = "["..session.type..(tostring(session):match("%x*$")).."]"
	end
end

local function session_flags(session, line)
	line = line or {};
	common_info(session, line);
	if session.type == "c2s" then
		local status, priority = "unavailable", tostring(session.priority or "-");
		if session.presence then
			status = session.presence:get_child_text("show") or "available";
		end
		line[#line+1] = status.."("..priority..")";
	end
	if session.cert_identity_status == "valid" then
		line[#line+1] = "(authenticated)";
	end
	if session.secure then
		line[#line+1] = "(encrypted)";
	end
	if session.compressed then
		line[#line+1] = "(compressed)";
	end
	if session.smacks then
		line[#line+1] = "(sm)";
	end
	if session.ip and session.ip:match(":") then
		line[#line+1] = "(IPv6)";
	end
	if session.remote then
		line[#line+1] = "(remote)";
	end
	if session.is_bidi then
		line[#line+1] = "(bidi)";
	end
	if session.bosh_version then
		line[#line+1] = "(bosh)";
	end
	if session.websocket_request then
		line[#line+1] = "(websocket)";
	end
	return table.concat(line, " ");
end

local function tls_info(session, line)
	line = line or {};
	common_info(session, line);
	if session.secure then
		local sock = session.conn and session.conn.socket and session.conn:socket();
		if sock and sock.info then
			local info = sock:info();
			line[#line+1] = ("(%s with %s)"):format(info.protocol, info.cipher);
		else
			line[#line+1] = "(cipher info unavailable)";
		end
	else
		line[#line+1] = "(insecure)";
	end
	return table.concat(line, " ");
end

def_env.c2s = {};

local function get_jid(session)
	if session.username then
		return session.full_jid or jid_join(session.username, session.host, session.resource);
	end

	local conn = session.conn;
	local ip = session.ip or "?";
	local clientport = conn and conn:clientport() or "?";
	local serverip = conn and conn.server and conn:server():ip() or "?";
	local serverport = conn and conn:serverport() or "?"
	return jid_join("["..ip.."]:"..clientport, session.host or "["..serverip.."]:"..serverport);
end

local function show_c2s(callback)
	local c2s = array.collect(values(module:shared"/*/c2s/sessions"));
	c2s:append(array.collect(values(module:shared"/*/bosh/sessions")));
	c2s:sort(function(a, b)
		if a.host == b.host then
			if a.username == b.username then
				return (a.resource or "") > (b.resource or "");
			end
			return (a.username or "") > (b.username or "");
		end
		return (a.host or "") > (b.host or "");
	end):map(function (session)
		callback(get_jid(session), session)
	end);
end

function def_env.c2s:count()
	local c2s_count = iterators.count(values(module:shared"/*/c2s/sessions"))
	local bosh_count = iterators.count(values(module:shared"/*/bosh/sessions"))
	return true, "Total: "..  c2s_count + bosh_count .." clients";
end

function def_env.c2s:show(match_jid, annotate)
	local print, count = self.session.print, 0;
	annotate = annotate or session_flags;
	local curr_host = false;
	show_c2s(function (jid, session)
		if curr_host ~= session.host then
			curr_host = session.host;
			print(curr_host or "(not connected to any host yet)");
		end
		if (not match_jid) or jid:match(match_jid) then
			count = count + 1;
			print(annotate(session, { "  ", jid }));
		end
	end);
	return true, "Total: "..count.." clients";
end

function def_env.c2s:show_insecure(match_jid)
	local print, count = self.session.print, 0;
	show_c2s(function (jid, session)
		if ((not match_jid) or jid:match(match_jid)) and not session.secure then
			count = count + 1;
			print(jid);
		end
	end);
	return true, "Total: "..count.." insecure client connections";
end

function def_env.c2s:show_secure(match_jid)
	local print, count = self.session.print, 0;
	show_c2s(function (jid, session)
		if ((not match_jid) or jid:match(match_jid)) and session.secure then
			count = count + 1;
			print(jid);
		end
	end);
	return true, "Total: "..count.." secure client connections";
end

function def_env.c2s:show_tls(match_jid)
	return self:show(match_jid, tls_info);
end

function def_env.c2s:close(match_jid)
	local count = 0;
	show_c2s(function (jid, session)
		if jid == match_jid or jid_bare(jid) == match_jid then
			count = count + 1;
			session:close();
		end
	end);
	return true, "Total: "..count.." sessions closed";
end

function def_env.c2s:closeall()
	local count = 0;
	--luacheck: ignore 212/jid
	show_c2s(function (jid, session)
		count = count + 1;
		session:close();
	end);
	return true, "Total: "..count.." sessions closed";
end


def_env.s2s = {};
function def_env.s2s:show(match_jid, annotate)
	local print = self.session.print;
	annotate = annotate or session_flags;

	local count_in, count_out = 0,0;
	local s2s_list = { };

	local s2s_sessions = module:shared"/*/s2s/sessions";
	for _, session in pairs(s2s_sessions) do
		local remotehost, localhost, direction;
		if session.direction == "outgoing" then
			direction = "->";
			count_out = count_out + 1;
			remotehost, localhost = session.to_host or "?", session.from_host or "?";
		else
			direction = "<-";
			count_in = count_in + 1;
			remotehost, localhost = session.from_host or "?", session.to_host or "?";
		end
		local sess_lines = { l = localhost, r = remotehost,
			annotate(session, { "", direction, remotehost or "?" })};

		if (not match_jid) or remotehost:match(match_jid) or localhost:match(match_jid) then
			table.insert(s2s_list, sess_lines);
			-- luacheck: ignore 421/print
			local print = function (s) table.insert(sess_lines, "        "..s); end
			if session.sendq then
				print("There are "..#session.sendq.." queued outgoing stanzas for this connection");
			end
			if session.type == "s2sout_unauthed" then
				if session.connecting then
					print("Connection not yet established");
					if not session.srv_hosts then
						if not session.conn then
							print("We do not yet have a DNS answer for this host's SRV records");
						else
							print("This host has no SRV records, using A record instead");
						end
					elseif session.srv_choice then
						print("We are on SRV record "..session.srv_choice.." of "..#session.srv_hosts);
						local srv_choice = session.srv_hosts[session.srv_choice];
						print("Using "..(srv_choice.target or ".")..":"..(srv_choice.port or 5269));
					end
				elseif session.notopen then
					print("The <stream> has not yet been opened");
				elseif not session.dialback_key then
					print("Dialback has not been initiated yet");
				elseif session.dialback_key then
					print("Dialback has been requested, but no result received");
				end
			end
			if session.type == "s2sin_unauthed" then
				print("Connection not yet authenticated");
			elseif session.type == "s2sin" then
				for name in pairs(session.hosts) do
					if name ~= session.from_host then
						print("also hosts "..tostring(name));
					end
				end
			end
		end
	end

	-- Sort by local host, then remote host
	table.sort(s2s_list, function(a,b)
		if a.l == b.l then return a.r < b.r; end
		return a.l < b.l;
	end);
	local lasthost;
	for _, sess_lines in ipairs(s2s_list) do
		if sess_lines.l ~= lasthost then print(sess_lines.l); lasthost=sess_lines.l end
		for _, line in ipairs(sess_lines) do print(line); end
	end
	return true, "Total: "..count_out.." outgoing, "..count_in.." incoming connections";
end

function def_env.s2s:show_tls(match_jid)
	return self:show(match_jid, tls_info);
end

local function print_subject(print, subject)
	for _, entry in ipairs(subject) do
		print(
			("    %s: %q"):format(
				entry.name or entry.oid,
				entry.value:gsub("[\r\n%z%c]", " ")
			)
		);
	end
end

-- As much as it pains me to use the 0-based depths that OpenSSL does,
-- I think there's going to be more confusion among operators if we
-- break from that.
local function print_errors(print, errors)
	for depth, t in pairs(errors) do
		print(
			("    %d: %s"):format(
				depth-1,
				table.concat(t, "\n|        ")
			)
		);
	end
end

function def_env.s2s:showcert(domain)
	local print = self.session.print;
	local s2s_sessions = module:shared"/*/s2s/sessions";
	local domain_sessions = set.new(array.collect(values(s2s_sessions)))
		/function(session) return (session.to_host == domain or session.from_host == domain) and session or nil; end;
	local cert_set = {};
	for session in domain_sessions do
		local conn = session.conn;
		conn = conn and conn:socket();
		if not conn.getpeerchain then
			if conn.dohandshake then
				error("This version of LuaSec does not support certificate viewing");
			end
		else
			local cert = conn:getpeercertificate();
			if cert then
				local certs = conn:getpeerchain();
				local digest = cert:digest("sha1");
				if not cert_set[digest] then
					local chain_valid, chain_errors = conn:getpeerverification();
					cert_set[digest] = {
						{
						  from = session.from_host,
						  to = session.to_host,
						  direction = session.direction
						};
						chain_valid = chain_valid;
						chain_errors = chain_errors;
						certs = certs;
					};
				else
					table.insert(cert_set[digest], {
						from = session.from_host,
						to = session.to_host,
						direction = session.direction
					});
				end
			end
		end
	end
	local domain_certs = array.collect(values(cert_set));
	-- Phew. We now have a array of unique certificates presented by domain.
	local n_certs = #domain_certs;

	if n_certs == 0 then
		return "No certificates found for "..domain;
	end

	local function _capitalize_and_colon(byte)
		return string.upper(byte)..":";
	end
	local function pretty_fingerprint(hash)
		return hash:gsub("..", _capitalize_and_colon):sub(1, -2);
	end

	for cert_info in values(domain_certs) do
		local certs = cert_info.certs;
		local cert = certs[1];
		print("---")
		print("Fingerprint (SHA1): "..pretty_fingerprint(cert:digest("sha1")));
		print("");
		local n_streams = #cert_info;
		print("Currently used on "..n_streams.." stream"..(n_streams==1 and "" or "s")..":");
		for _, stream in ipairs(cert_info) do
			if stream.direction == "incoming" then
				print("    "..stream.to.." <- "..stream.from);
			else
				print("    "..stream.from.." -> "..stream.to);
			end
		end
		print("");
		local chain_valid, errors = cert_info.chain_valid, cert_info.chain_errors;
		local valid_identity = cert_verify_identity(domain, "xmpp-server", cert);
		if chain_valid then
			print("Trusted certificate: Yes");
		else
			print("Trusted certificate: No");
			print_errors(print, errors);
		end
		print("");
		print("Issuer: ");
		print_subject(print, cert:issuer());
		print("");
		print("Valid for "..domain..": "..(valid_identity and "Yes" or "No"));
		print("Subject:");
		print_subject(print, cert:subject());
	end
	print("---");
	return ("Showing "..n_certs.." certificate"
		..(n_certs==1 and "" or "s")
		.." presented by "..domain..".");
end

function def_env.s2s:close(from, to)
	local print, count = self.session.print, 0;
	local s2s_sessions = module:shared"/*/s2s/sessions";

	local match_id;
	if from and not to then
		match_id, from = from, nil;
	elseif not to then
		return false, "Syntax: s2s:close('from', 'to') - Closes all s2s sessions from 'from' to 'to'";
	elseif from == to then
		return false, "Both from and to are the same... you can't do that :)";
	end

	for _, session in pairs(s2s_sessions) do
		local id = session.type..tostring(session):match("[a-f0-9]+$");
		if (match_id and match_id == id)
		or (session.from_host == from and session.to_host == to) then
			print(("Closing connection from %s to %s [%s]"):format(session.from_host, session.to_host, id));
			(session.close or s2smanager.destroy_session)(session);
			count = count + 1 ;
		end
	end
	return true, "Closed "..count.." s2s session"..((count == 1 and "") or "s");
end

function def_env.s2s:closeall(host)
	local count = 0;
	local s2s_sessions = module:shared"/*/s2s/sessions";
	for _,session in pairs(s2s_sessions) do
		if not host or session.from_host == host or session.to_host == host then
			session:close();
			count = count + 1;
		end
	end
	if count == 0 then return false, "No sessions to close.";
	else return true, "Closed "..count.." s2s session"..((count == 1 and "") or "s"); end
end

def_env.host = {}; def_env.hosts = def_env.host;

function def_env.host:activate(hostname, config)
	return hostmanager.activate(hostname, config);
end
function def_env.host:deactivate(hostname, reason)
	return hostmanager.deactivate(hostname, reason);
end

function def_env.host:list()
	local print = self.session.print;
	local i = 0;
	local type;
	for host, host_session in iterators.sorted_pairs(prosody.hosts) do
		i = i + 1;
		type = host_session.type;
		if type == "local" then
			print(host);
		else
			type = module:context(host):get_option_string("component_module", type);
			if type ~= "component" then
				type = type .. " component";
			end
			print(("%s (%s)"):format(host, type));
		end
	end
	return true, i.." hosts";
end

def_env.port = {};

function def_env.port:list()
	local print = self.session.print;
	local services = portmanager.get_active_services().data;
	local n_services, n_ports = 0, 0;
	for service, interfaces in iterators.sorted_pairs(services) do
		n_services = n_services + 1;
		local ports_list = {};
		for interface, ports in pairs(interfaces) do
			for port in pairs(ports) do
				table.insert(ports_list, "["..interface.."]:"..port);
			end
		end
		n_ports = n_ports + #ports_list;
		print(service..": "..table.concat(ports_list, ", "));
	end
	return true, n_services.." services listening on "..n_ports.." ports";
end

function def_env.port:close(close_port, close_interface)
	close_port = assert(tonumber(close_port), "Invalid port number");
	local n_closed = 0;
	local services = portmanager.get_active_services().data;
	for service, interfaces in pairs(services) do -- luacheck: ignore 213
		for interface, ports in pairs(interfaces) do
			if not close_interface or close_interface == interface then
				if ports[close_port] then
					self.session.print("Closing ["..interface.."]:"..close_port.."...");
					local ok, err = portmanager.close(interface, close_port)
					if not ok then
						self.session.print("Failed to close "..interface.." "..close_port..": "..err);
					else
						n_closed = n_closed + 1;
					end
				end
			end
		end
	end
	return true, "Closed "..n_closed.." ports";
end

def_env.muc = {};

local console_room_mt = {
	__index = function (self, k) return self.room[k]; end;
	__tostring = function (self)
		return "MUC room <"..self.room.jid..">";
	end;
};

local function check_muc(jid)
	local room_name, host = jid_split(jid);
	if not prosody.hosts[host] then
		return nil, "No such host: "..host;
	elseif not prosody.hosts[host].modules.muc then
		return nil, "Host '"..host.."' is not a MUC service";
	end
	return room_name, host;
end

function def_env.muc:create(room_jid, config)
	local room_name, host = check_muc(room_jid);
	if not room_name then
		return room_name, host;
	end
	if not room_name then return nil, host end
	if config ~= nil and type(config) ~= "table" then return nil, "Config must be a table"; end
	if prosody.hosts[host].modules.muc.get_room_from_jid(room_jid) then return nil, "Room exists already" end
	return prosody.hosts[host].modules.muc.create_room(room_jid, config);
end

function def_env.muc:room(room_jid)
	local room_name, host = check_muc(room_jid);
	if not room_name then
		return room_name, host;
	end
	local room_obj = prosody.hosts[host].modules.muc.get_room_from_jid(room_jid);
	if not room_obj then
		return nil, "No such room: "..room_jid;
	end
	return setmetatable({ room = room_obj }, console_room_mt);
end

function def_env.muc:list(host)
	local host_session = prosody.hosts[host];
	if not host_session or not host_session.modules.muc then
		return nil, "Please supply the address of a local MUC component";
	end
	local print = self.session.print;
	local c = 0;
	for room in host_session.modules.muc.each_room() do
		print(room.jid);
		c = c + 1;
	end
	return true, c.." rooms";
end

local um = require"core.usermanager";

def_env.user = {};
function def_env.user:create(jid, password)
	local username, host = jid_split(jid);
	if not prosody.hosts[host] then
		return nil, "No such host: "..host;
	elseif um.user_exists(username, host) then
		return nil, "User exists";
	end
	local ok, err = um.create_user(username, password, host);
	if ok then
		return true, "User created";
	else
		return nil, "Could not create user: "..err;
	end
end

function def_env.user:delete(jid)
	local username, host = jid_split(jid);
	if not prosody.hosts[host] then
		return nil, "No such host: "..host;
	elseif not um.user_exists(username, host) then
		return nil, "No such user";
	end
	local ok, err = um.delete_user(username, host);
	if ok then
		return true, "User deleted";
	else
		return nil, "Could not delete user: "..err;
	end
end

function def_env.user:password(jid, password)
	local username, host = jid_split(jid);
	if not prosody.hosts[host] then
		return nil, "No such host: "..host;
	elseif not um.user_exists(username, host) then
		return nil, "No such user";
	end
	local ok, err = um.set_password(username, password, host, nil);
	if ok then
		return true, "User password changed";
	else
		return nil, "Could not change password for user: "..err;
	end
end

function def_env.user:list(host, pat)
	if not host then
		return nil, "No host given";
	elseif not prosody.hosts[host] then
		return nil, "No such host";
	end
	local print = self.session.print;
	local total, matches = 0, 0;
	for user in um.users(host) do
		if not pat or user:match(pat) then
			print(user.."@"..host);
			matches = matches + 1;
		end
		total = total + 1;
	end
	return true, "Showing "..(pat and (matches.." of ") or "all " )..total.." users";
end

def_env.xmpp = {};

local st = require "util.stanza";
local new_id = require "util.id".medium;
function def_env.xmpp:ping(localhost, remotehost, timeout)
	localhost = select(2, jid_split(localhost));
	remotehost = select(2, jid_split(remotehost));
	if not localhost then
		return nil, "Invalid sender hostname";
	elseif not prosody.hosts[localhost] then
		return nil, "No such local host";
	end
	if not remotehost then
		return nil, "Invalid destination hostname";
	elseif prosody.hosts[remotehost] then
		return nil, "Both hosts are local";
	end
	local iq = st.iq{ from=localhost, to=remotehost, type="get", id=new_id()}
			:tag("ping", {xmlns="urn:xmpp:ping"});
	local ret, err;
	local wait, done = async.waiter();
	module:context(localhost):send_iq(iq, nil, timeout)
		:next(function (ret_) ret = ret_; end,
			function (err_) err = err_; end)
		:finally(done);
	wait();
	if ret then
		return true, "pong from " .. ret.stanza.attr.from;
	else
		return false, tostring(err);
	end
end

def_env.dns = {};
local adns = require"net.adns";
local dns = require"net.dns";

function def_env.dns:lookup(name, typ, class)
	local ret = "Query sent";
	local print = self.session.print;
	local function handler(...)
		ret = "Got response";
		print(...);
	end
	adns.lookup(handler, name, typ, class);
	return true, ret;
end

function def_env.dns:addnameserver(...)
	dns._resolver:addnameserver(...)
	return true
end

function def_env.dns:setnameserver(...)
	dns._resolver:setnameserver(...)
	return true
end

function def_env.dns:purge()
	dns.purge()
	return true
end

function def_env.dns:cache()
	return true, "Cache:\n"..tostring(dns.cache())
end

def_env.http = {};

function def_env.http:list()
	local print = self.session.print;

	for host in pairs(prosody.hosts) do
		local http_apps = modulemanager.get_items("http-provider", host);
		if #http_apps > 0 then
			local http_host = module:context(host):get_option_string("http_host");
			print("HTTP endpoints on "..host..(http_host and (" (using "..http_host.."):") or ":"));
			for _, provider in ipairs(http_apps) do
				local url = module:context(host):http_url(provider.name, provider.default_path);
				print("", url);
			end
			print("");
		end
	end

	local default_host = module:get_option_string("http_default_host");
	if not default_host then
		print("HTTP requests to unknown hosts will return 404 Not Found");
	else
		print("HTTP requests to unknown hosts will be handled by "..default_host);
	end
	return true;
end

def_env.debug = {};

function def_env.debug:logevents(host)
	helpers.log_host_events(host);
	return true;
end

function def_env.debug:events(host, event)
	local events_obj;
	if host and host ~= "*" then
		if host == "http" then
			events_obj = require "net.http.server"._events;
		elseif not prosody.hosts[host] then
			return false, "Unknown host: "..host;
		else
			events_obj = prosody.hosts[host].events;
		end
	else
		events_obj = prosody.events;
	end
	return true, helpers.show_events(events_obj, event);
end

function def_env.debug:timers()
	local socket = require "socket";
	local print = self.session.print;
	local add_task = require"util.timer".add_task;
	local h, params = add_task.h, add_task.params;
	if h then
		print("-- util.timer");
		for i, id in ipairs(h.ids) do
			if not params[id] then
				print(os.date("%F %T", h.priorities[i]), h.items[id]);
			elseif not params[id].callback then
				print(os.date("%F %T", h.priorities[i]), h.items[id], unpack(params[id]));
			else
				print(os.date("%F %T", h.priorities[i]), params[id].callback, unpack(params[id]));
			end
		end
	end
	if server.event_base then
		local count = 0;
		for _, v in pairs(debug.getregistry()) do
			if type(v) == "function" and v.callback and v.callback == add_task._on_timer then
				count = count + 1;
			end
		end
		print(count .. " libevent callbacks");
	end
	if h then
		local next_time = h:peek();
		if next_time then
			return true, os.date("Next event at %F %T (in %%.6fs)", next_time):format(next_time - socket.gettime());
		end
	end
	return true;
end

-- COMPAT: debug:timers() was timer:info() for some time in trunk
def_env.timer = { info = def_env.debug.timers };

module:hook("server-stopping", function(event)
	for _, session in pairs(sessions) do
		session.print("Shutting down: "..(event.reason or "unknown reason"));
	end
end);

def_env.stats = {};

local function format_stat(type, value, ref_value)
	ref_value = ref_value or value;
	--do return tostring(value) end
	if type == "duration" then
		if ref_value < 0.001 then
			return ("%g µs"):format(value*1000000);
		elseif ref_value < 0.9 then
			return ("%0.2f ms"):format(value*1000);
		end
		return ("%0.2f"):format(value);
	elseif type == "size" then
		if ref_value > 1048576 then
			return ("%d MB"):format(value/1048576);
		elseif ref_value > 1024 then
			return ("%d KB"):format(value/1024);
		end
		return ("%d bytes"):format(value);
	elseif type == "rate" then
		if ref_value < 0.9 then
			return ("%0.2f/min"):format(value*60);
		end
		return ("%0.2f/sec"):format(value);
	end
	return tostring(value);
end

local stats_methods = {};
function stats_methods:bounds(_lower, _upper)
	for _, stat_info in ipairs(self) do
		local data = stat_info[4];
		if data then
			local lower = _lower or data.min;
			local upper = _upper or data.max;
			local new_data = {
				min = lower;
				max = upper;
				samples = {};
				sample_count = 0;
				count = data.count;
				units = data.units;
			};
			local sum = 0;
			for _, v in ipairs(data.samples) do
				if v > upper then
					break;
				elseif v>=lower then
					table.insert(new_data.samples, v);
					sum = sum + v;
				end
			end
			new_data.sample_count = #new_data.samples;
			stat_info[4] = new_data;
			stat_info[3] = sum/new_data.sample_count;
		end
	end
	return self;
end

function stats_methods:trim(lower, upper)
	upper = upper or (100-lower);
	local statistics = require "util.statistics";
	for _, stat_info in ipairs(self) do
		-- Strip outliers
		local data = stat_info[4];
		if data then
			local new_data = {
				min = statistics.get_percentile(data, lower);
				max = statistics.get_percentile(data, upper);
				samples = {};
				sample_count = 0;
				count = data.count;
				units = data.units;
			};
			local sum = 0;
			for _, v in ipairs(data.samples) do
				if v > new_data.max then
					break;
				elseif v>=new_data.min then
					table.insert(new_data.samples, v);
					sum = sum + v;
				end
			end
			new_data.sample_count = #new_data.samples;
			stat_info[4] = new_data;
			stat_info[3] = sum/new_data.sample_count;
		end
	end
	return self;
end

function stats_methods:max(upper)
	return self:bounds(nil, upper);
end

function stats_methods:min(lower)
	return self:bounds(lower, nil);
end

function stats_methods:summary()
	local statistics = require "util.statistics";
	for _, stat_info in ipairs(self) do
		local type, value, data = stat_info[2], stat_info[3], stat_info[4];
		if data and data.samples then
			table.insert(stat_info.output, string.format("Count: %d (%d captured)",
				data.count,
				data.sample_count
			));
			table.insert(stat_info.output, string.format("Min: %s  Mean: %s  Max: %s",
				format_stat(type, data.min),
				format_stat(type, value),
				format_stat(type, data.max)
			));
			table.insert(stat_info.output, string.format("Q1: %s  Median: %s  Q3: %s",
				format_stat(type, statistics.get_percentile(data, 25)),
				format_stat(type, statistics.get_percentile(data, 50)),
				format_stat(type, statistics.get_percentile(data, 75))
			));
		end
	end
	return self;
end

function stats_methods:cfgraph()
	for _, stat_info in ipairs(self) do
		local name, type, value, data = unpack(stat_info, 1, 4);
		local function print(s)
			table.insert(stat_info.output, s);
		end

		if data and data.sample_count and data.sample_count > 0 then
			local raw_histogram = require "util.statistics".get_histogram(data);

			local graph_width, graph_height = 50, 10;
			local eighth_chars = "   ▁▂▃▄▅▆▇█";

			local range = data.max - data.min;

			if range > 0 then
				local x_scaling = #raw_histogram/graph_width;
				local histogram = {};
				for i = 1, graph_width do
					histogram[i] = math.max(raw_histogram[i*x_scaling-1] or 0, raw_histogram[i*x_scaling] or 0);
				end

				print("");
				print(("_"):rep(52)..format_stat(type, data.max));
				for row = graph_height, 1, -1 do
					local row_chars = {};
					local min_eighths, max_eighths = 8, 0;
					for i = 1, #histogram do
						local char_eighths = math.ceil(math.max(math.min((graph_height/(data.max/histogram[i]))-(row-1), 1), 0)*8);
						if char_eighths < min_eighths then
							min_eighths = char_eighths;
						end
						if char_eighths > max_eighths then
							max_eighths = char_eighths;
						end
						if char_eighths == 0 then
							row_chars[i] = "-";
						else
							local char = eighth_chars:sub(char_eighths*3+1, char_eighths*3+3);
							row_chars[i] = char;
						end
					end
					print(table.concat(row_chars).."|-"..format_stat(type, data.max/(graph_height/(row-0.5))));
				end
				print(("\\    "):rep(11));
				local x_labels = {};
				for i = 1, 11 do
					local s = ("%-4s"):format((i-1)*10);
					if #s > 4 then
						s = s:sub(1, 3).."…";
					end
					x_labels[i] = s;
				end
				print(" "..table.concat(x_labels, " "));
				local units = "%";
				local margin = math.floor((graph_width-#units)/2);
				print((" "):rep(margin)..units);
			else
				print("[range too small to graph]");
			end
			print("");
		end
	end
	return self;
end

function stats_methods:histogram()
	for _, stat_info in ipairs(self) do
		local name, type, value, data = unpack(stat_info, 1, 4);
		local function print(s)
			table.insert(stat_info.output, s);
		end

		if not data then
			print("[no data]");
			return self;
		elseif not data.sample_count then
			print("[not a sampled metric type]");
			return self;
		end

		local graph_width, graph_height = 50, 10;
		local eighth_chars = "   ▁▂▃▄▅▆▇█";

		local range = data.max - data.min;

		if range > 0 then
			local n_buckets = graph_width;

			local histogram = {};
			for i = 1, n_buckets do
				histogram[i] = 0;
			end
			local max_bin_samples = 0;
			for _, d in ipairs(data.samples) do
				local bucket = math.floor(1+(n_buckets-1)/(range/(d-data.min)));
				histogram[bucket] = histogram[bucket] + 1;
				if histogram[bucket] > max_bin_samples then
					max_bin_samples = histogram[bucket];
				end
			end

			print("");
			print(("_"):rep(52)..max_bin_samples);
			for row = graph_height, 1, -1 do
				local row_chars = {};
				local min_eighths, max_eighths = 8, 0;
				for i = 1, #histogram do
					local char_eighths = math.ceil(math.max(math.min((graph_height/(max_bin_samples/histogram[i]))-(row-1), 1), 0)*8);
					if char_eighths < min_eighths then
						min_eighths = char_eighths;
					end
					if char_eighths > max_eighths then
						max_eighths = char_eighths;
					end
					if char_eighths == 0 then
						row_chars[i] = "-";
					else
						local char = eighth_chars:sub(char_eighths*3+1, char_eighths*3+3);
						row_chars[i] = char;
					end
				end
				print(table.concat(row_chars).."|-"..math.ceil((max_bin_samples/graph_height)*(row-0.5)));
			end
			print(("\\    "):rep(11));
			local x_labels = {};
			for i = 1, 11 do
				local s = ("%-4s"):format(format_stat(type, data.min+range*i/11, data.min):match("^%S+"));
				if #s > 4 then
					s = s:sub(1, 3).."…";
				end
				x_labels[i] = s;
			end
			print(" "..table.concat(x_labels, " "));
			local units = format_stat(type, data.min):match("%s+(.+)$") or data.units or "";
			local margin = math.floor((graph_width-#units)/2);
			print((" "):rep(margin)..units);
		else
			print("[range too small to graph]");
		end
		print("");
	end
	return self;
end

local function stats_tostring(stats)
	local print = stats.session.print;
	for _, stat_info in ipairs(stats) do
		if #stat_info.output > 0 then
			print("\n#"..stat_info[1]);
			print("");
			for _, v in ipairs(stat_info.output) do
				print(v);
			end
			print("");
		else
			print(("%-50s %s"):format(stat_info[1], format_stat(stat_info[2], stat_info[3])));
		end
	end
	return #stats.." statistics displayed";
end

local stats_mt = {__index = stats_methods, __tostring = stats_tostring }
local function new_stats_context(self)
	return setmetatable({ session = self.session, stats = true }, stats_mt);
end

function def_env.stats:show(filter)
	local stats, changed, extra = require "core.statsmanager".get_stats();
	local available, displayed = 0, 0;
	local displayed_stats = new_stats_context(self);
	for name, value in iterators.sorted_pairs(stats) do
		available = available + 1;
		if not filter or name:match(filter) then
			displayed = displayed + 1;
			local type = name:match(":(%a+)$");
			table.insert(displayed_stats, {
				name, type, value, extra[name];
				output = {};
			});
		end
	end
	return displayed_stats;
end



-------------

function printbanner(session)
	local option = module:get_option_string("console_banner", "full");
	if option == "full" or option == "graphic" then
		session.print [[
                   ____                \   /     _
                    |  _ \ _ __ ___  ___  _-_   __| |_   _
                    | |_) | '__/ _ \/ __|/ _ \ / _` | | | |
                    |  __/| | | (_) \__ \ |_| | (_| | |_| |
                    |_|   |_|  \___/|___/\___/ \__,_|\__, |
                    A study in simplicity            |___/

]]
	end
	if option == "short" or option == "full" then
	session.print("Welcome to the Prosody administration console. For a list of commands, type: help");
	session.print("You may find more help on using this console in our online documentation at ");
	session.print("https://prosody.im/doc/console\n");
	end
	if option ~= "short" and option ~= "full" and option ~= "graphic" then
		session.print(option);
	end
end

module:provides("net", {
	name = "console";
	listener = console_listener;
	default_port = 5582;
	private = true;
});