File

plugins/mod_admin_shell.lua @ 12579:ca6a43fe0231 0.12

util.jsonschema: Fix validation to not assume presence of "type" field MattJ reported a curious issue where validation did not work as expected. Primarily that the "type" field was expected to be mandatory, and thus leaving it out would result in no checks being performed. This was likely caused by misreading during initial development. Spent some time testing against https://github.com/json-schema-org/JSON-Schema-Test-Suite.git and discovered a multitude of issues, far too many to bother splitting into separate commits. More than half of them fail. Many because of features not implemented, which have been marked NYI. For example, some require deep comparisons e.g. when objects or arrays are present in enums fields. Some because of quirks with how Lua differs from JavaScript, e.g. no distinct array or object types. Tests involving fractional floating point numbers. We're definitely not going to follow references to remote resources. Or deal with UTF-16 sillyness. One test asserted that 1.0 is an integer, where Lua 5.3+ will disagree.
author Kim Alvefur <zash@zash.se>
date Fri, 08 Jul 2022 14:38:23 +0200
parent 12505:604bb5b8362d
child 12506:d04f6f014636
child 12637:2200f0c6b3f1
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();
module:depends("admin_socket");

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 st = require "util.stanza";

local _G = _G;

local prosody = _G.prosody;

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 serialization = require "util.serialization";
local serialize_config = serialization.new ({ fatal = false, unquoted = true});
local time = require "util.time";
local promise = require "util.promise";

local t_insert = table.insert;
local t_concat = table.concat;

local format_number = require "util.human.units".format;
local format_table = require "util.human.io".table;

local function capitalize(s)
	if not s then return end
	return (s:gsub("^%a", string.upper):gsub("_", " "));
end

local function pre(prefix, str, alt)
	if type(str) ~= "string" or str == "" then return alt or ""; end
	return prefix .. str;
end

local function suf(str, suffix, alt)
	if type(str) ~= "string" or str == "" then return alt or ""; end
	return str .. suffix;
end

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:error(err)
	module:log("error", "Traceback[shell]: %s", err);

	self.data.print("Fatal error while running command, it did not complete");
	self.data.print("Error: "..tostring(err));
end

local function send_repl_output(session, line)
	return session.send(st.stanza("repl-output"):text(tostring(line)));
end

function console:new_session(admin_session)
	local session = {
		send = function (t)
			return send_repl_output(admin_session, t);
		end;
		print = function (...)
			local t = {};
			for i=1,select("#", ...) do
				t[i] = tostring(select(i, ...));
			end
			return send_repl_output(admin_session, table.concat(t, "\t"));
		end;
		serialize = tostring;
		disconnect = function () admin_session:close(); end;
	};
	session.env = setmetatable({}, default_env_mt);

	session.thread = async.runner(function (line)
		console:process_line(session, line);
	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

	session.env.output:configure();

	return session;
end

local function handle_line(event)
	local session = event.origin.shell_session;
	if not session then
		session = console:new_session(event.origin);
		event.origin.shell_session = session;
	end
	local line = event.stanza:get_text();
	local useglobalenv;

	local result = st.stanza("repl-result");

	if line:match("^>") then
		line = line:gsub("^>", "");
		useglobalenv = true;
	else
		local command = line:match("^%w+") or line:match("%p");
		if commands[command] then
			commands[command](session, line);
			event.origin.send(result);
			return;
		end
	end

	session.env._ = line;

	if not useglobalenv and commands[line:lower()] then
		commands[line:lower()](session, line);
		event.origin.send(result);
		return;
	end

	if useglobalenv and not session.globalenv then
		session.globalenv = redirect_output(_G, session);
	end

	local chunkname = "=console";
	local env = (useglobalenv and session.globalenv) or session.env or nil
	-- luacheck: ignore 311/err
	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");
			result.attr.type = "error";
			result:text("Sorry, I couldn't understand that... "..err);
			event.origin.send(result);
			return;
		end
	end

	local taskok, message = chunk();

	if promise.is_promise(taskok) then
		taskok, message = async.wait_for(taskok);
	end

	if not message then
		if type(taskok) ~= "string" and useglobalenv then
			taskok = session.serialize(taskok);
		end
		result:text("Result: "..tostring(taskok));
	elseif (not taskok) and message then
		result.attr.type = "error";
		result:text("Error: "..tostring(message));
	else
		result:text("OK: "..tostring(message));
	end

	event.origin.send(result);
end

module:hook("admin/repl-input", function (event)
	local ok, err = pcall(handle_line, event);
	if not ok then
		event.origin.send(st.stanza("repl-result", { type = "error" }):text(err));
	end
end);

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

local available_columns; --forward declaration so it is reachable from the help

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 [[]]
		local row = format_table({ { title = "Section"; width = 7 }; { title = "Description"; width = "100%" } })
		print(row())
		print(row { "c2s"; "Commands to manage local client-to-server sessions" })
		print(row { "s2s"; "Commands to manage sessions between this server and others" })
		print(row { "http"; "Commands to inspect HTTP services" }) -- XXX plural but there is only one so far
		print(row { "module"; "Commands to load/reload/unload modules/plugins" })
		print(row { "host"; "Commands to activate, deactivate and list virtual hosts" })
		print(row { "user"; "Commands to create and delete users, and change their passwords" })
		print(row { "roles"; "Show information about user roles" })
		print(row { "muc"; "Commands to create, list and manage chat rooms" })
		print(row { "stats"; "Commands to show internal statistics" })
		print(row { "server"; "Uptime, version, shutting down, etc." })
		print(row { "port"; "Commands to manage ports the server is listening on" })
		print(row { "dns"; "Commands to manage and inspect the internal DNS resolver" })
		print(row { "xmpp"; "Commands for sending XMPP stanzas" })
		print(row { "debug"; "Commands for debugging the server" })
		print(row { "config"; "Reloading the configuration, etc." })
		print(row { "columns"; "Information about customizing session listings" })
		print(row { "console"; "Help regarding the console itself" })
	elseif section == "c2s" then
		print [[c2s:show(jid, columns) - Show all client sessions with the specified JID (or all if no JID given)]]
		print [[c2s:show_tls(jid) - Show TLS cipher info for encrypted sessions]]
		print [[c2s:count() - Count sessions without listing them]]
		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, columns) - 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 == "http" then
		print [[http:list(hosts) - Show HTTP endpoints]]
	elseif section == "module" then
		print [[module:info(module, host) - Show information about a loaded module]]
		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, roles) - Create the specified user account]]
		print [[user:password(jid, password) - Set the password for the specified user account]]
		print [[user:showroles(jid, host) - Show current roles for an user]]
		print [[user:roles(jid, host, roles) - Set roles for an user (see 'help roles')]]
		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 == "roles" then
		print [[Roles may grant access or restrict users from certain operations]]
		print [[Built-in roles are:]]
		print [[  prosody:admin - Administrator]]
		print [[  (empty set) - Normal user]]
		print [[]]
		print [[The canonical role format looks like: { ["example:role"] = true }]]
		print [[For convenience, the following formats are also accepted:]]
		print [["admin" - short for "prosody:admin", the normal admin status (like the admins config option)]]
		print [["example:role" - short for {["example:role"]=true}]]
		print [[{"example:role"} - short for {["example:role"]=true}]]
	elseif section == "muc" then
		-- TODO `muc:room():foo()` commands
		print [[muc:create(roomjid, { config }) - Create the specified MUC room with the given config]]
		print [[muc:list(host) - List rooms on the specified MUC component]]
		print [[muc:room(roomjid) - Reference the specified MUC room to access MUC API methods]]
	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 == "xmpp" then
		print [[xmpp:ping(localhost, remotehost) -- Sends a ping to a remote XMPP server and reports the response]]
	elseif section == "config" then
		print [[config:reload() - Reload the server configuration. Modules may need to be reloaded for changes to take effect.]]
		print [[config:get([host,] option) - Show the value of a config option.]]
	elseif section == "stats" then -- luacheck: ignore 542
		print [[stats:show(pattern) - Show internal statistics, optionally filtering by name with a pattern]]
		print [[stats:show():cfgraph() - Show a cumulative frequency graph]]
		print [[stats:show():histogram() - Show a histogram of selected metric]]
	elseif section == "debug" then
		print [[debug:logevents(host) - Enable logging of fired events on host]]
		print [[debug:events(host, event) - Show registered event handlers]]
		print [[debug:timers() - Show information about scheduled timers]]
	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 :)]]
	elseif section == "columns" then
		print [[The columns shown by c2s:show() and s2s:show() can be customizied via the]]
		print [['columns' argument as described here.]]
		print [[]]
		print [[Columns can be specified either as "id jid ipv" or as {"id", "jid", "ipv"}.]]
		print [[Available columns are:]]
		local meta_columns = {
			{ title = "ID"; width = 5 };
			{ title = "Column Title"; width = 12 };
			{ title = "Description"; width = 12 };
		};
		-- auto-adjust widths
		for column, spec in pairs(available_columns) do
			meta_columns[1].width = math.max(meta_columns[1].width or 0, #column);
			meta_columns[2].width = math.max(meta_columns[2].width or 0, #(spec.title or ""));
			meta_columns[3].width = math.max(meta_columns[3].width or 0, #(spec.description or ""));
		end
		local row = format_table(meta_columns, 120)
		print(row());
		for column, spec in iterators.sorted_pairs(available_columns) do
			print(row({ column, spec.title, spec.description }));
		end
		print [[]]
		print [[Most fields on the internal session structures can also be used as columns]]
		-- Also, you can pass a table column specification directly, with mapper callback and all
	end
end

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

--luacheck: ignore 212/self
local serialize_defaults = module:get_option("console_prettyprint_settings",
	{ fatal = false; unquoted = true; maxdepth = 2; table_iterator = "pairs" })

def_env.output = {};
function def_env.output:configure(opts)
	if type(opts) ~= "table" then
		opts = { preset = opts };
	end
	if not opts.fallback then
		-- XXX Error message passed to fallback is lost, does it matter?
		opts.fallback = tostring;
	end
	for k,v in pairs(serialize_defaults) do
		if opts[k] == nil then
			opts[k] = v;
		end
	end
	if opts.table_iterator == "pairs" then
		opts.table_iterator = pairs;
	elseif type(opts.table_iterator) ~= "function" then
		opts.table_iterator = nil; -- rawpairs is the default
	end
	self.session.serialize = serialization.new(opts);
end

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, code)
	prosody.shutdown(reason, code);
	return true, "Shutdown initiated";
end

local function human(kb)
	return format_number(kb*1024, "B", "b");
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)
	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
		return set.new(array.collect(keys(prosody.hosts)));
	end
end

-- Hosts with a module or all virtualhosts if no module given
-- matching modules_enabled in the global section
local function get_hosts_with_module(hosts, module)
	local hosts_set = get_hosts_set(hosts)
	/ function (host)
			if module then
				-- Module given, filter in hosts with this module loaded
				if modulemanager.is_loaded(host, module) then
					return host;
				else
					return nil;
				end
			end
			if not hosts then
				-- No hosts given, filter in VirtualHosts
				if prosody.hosts[host].type == "local" then
					return host;
				else
					return nil
				end
			end;
			-- No module given, but hosts are, don't filter at all
			return host;
		end;
	if module and modulemanager.get_module("*", module) then
		hosts_set:add("*");
	end
	return hosts_set;
end

function def_env.module:info(name, hosts)
	if not name then
		return nil, "module name expected";
	end
	local print = self.session.print;
	hosts = get_hosts_with_module(hosts, name);
	if hosts:empty() then
		return false, "mod_" .. name .. " does not appear to be loaded on the specified hosts";
	end

	local function item_name(item) return item.name; end

	local friendly_descriptions = {
		["adhoc-provider"] = "Ad-hoc commands",
		["auth-provider"] = "Authentication provider",
		["http-provider"] = "HTTP services",
		["net-provider"] = "Network service",
		["storage-provider"] = "Storage driver",
		["measure"] = "Legacy metrics",
		["metric"] = "Metrics",
		["task"] = "Periodic task",
	};
	local item_formatters = {
		["feature"] = tostring,
		["identity"] = function(ident) return ident.type .. "/" .. ident.category; end,
		["adhoc-provider"] = item_name,
		["auth-provider"] = item_name,
		["storage-provider"] = item_name,
		["http-provider"] = function(item, mod) return mod:http_url(item.name, item.default_path); end,
		["net-provider"] = item_name,
		["measure"] = function(item) return item.name .. " (" .. suf(item.conf and item.conf.unit, " ") .. item.type .. ")"; end,
		["metric"] = function(item)
			return ("%s (%s%s)%s"):format(item.name, suf(item.mf.unit, " "), item.mf.type_, pre(": ", item.mf.description));
		end,
		["task"] = function (item) return string.format("%s (%s)", item.name or item.id, item.when); end
	};

	for host in hosts do
		local mod = modulemanager.get_module(host, name);
		if mod.module.host == "*" then
			print("in global context");
		else
			print("on " .. tostring(prosody.hosts[mod.module.host]));
		end
		print("  path: " .. (mod.module.path or "n/a"));
		if mod.module.status_message then
			print("  status: [" .. mod.module.status_type .. "] " .. mod.module.status_message);
		end
		if mod.module.items and next(mod.module.items) ~= nil then
			print("  provides:");
			for kind, items in pairs(mod.module.items) do
				local label = friendly_descriptions[kind] or kind:gsub("%-", " "):gsub("^%a", string.upper);
				print(string.format("  - %s (%d item%s)", label, #items, #items > 1 and "s" or ""));
				local formatter = item_formatters[kind];
				if formatter then
					for _, item in ipairs(items) do
						print("    - " .. formatter(item, mod.module));
					end
				end
			end
		end
		if mod.module.dependencies and next(mod.module.dependencies) ~= nil then
			print("  dependencies:");
			for dep in pairs(mod.module.dependencies) do
				print("  - mod_" .. dep);
			end
		end
	end
	return true;
end

function def_env.module:load(name, hosts, config)
	hosts = get_hosts_with_module(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_with_module(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:gsub("[^.]+", string.reverse):reverse() < b:gsub("[^.]+", string.reverse):reverse(); end
end

function def_env.module:reload(name, hosts)
	hosts = array.collect(get_hosts_with_module(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)
	hosts = array.collect(set.new({ not hosts and "*" or nil }) + get_hosts_set(hosts)):sort(_sort_hosts);

	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(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

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 get_c2s()
	local c2s = array.collect(values(prosody.full_sessions));
	c2s:append(array.collect(values(module:shared"/*/c2s/sessions")));
	c2s:append(array.collect(values(module:shared"/*/bosh/sessions")));
	c2s:unique();
	return c2s;
end

local function _sort_by_jid(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 _sort_hosts(a.host or "", b.host or "");
end

local function show_c2s(callback)
	get_c2s():sort(_sort_by_jid):map(function (session)
		callback(get_jid(session), session)
	end);
end

function def_env.c2s:count()
	local c2s = get_c2s();
	return true, "Total: "..  #c2s .." clients";
end

local function get_s2s_hosts(session) --> local,remote
	if session.direction == "outgoing" then
		return session.host or session.from_host, session.to_host;
	elseif session.direction == "incoming" then
		return session.host or session.to_host, session.from_host;
	end
end

available_columns = {
	jid = {
		title = "JID";
		description = "Full JID of user session";
		width = 32;
		key = "full_jid";
		mapper = function(full_jid, session) return full_jid or get_jid(session) end;
	};
	host = {
		title = "Host";
		description = "Local hostname";
		key = "host";
		width = 22;
		mapper = function(host, session)
			return host or get_s2s_hosts(session) or "?";
		end;
	};
	remote = {
		title = "Remote";
		description = "Remote hostname";
		width = 22;
		mapper = function(_, session)
			return select(2, get_s2s_hosts(session));
		end;
	};
	port = {
		title = "Port";
		description = "Server port used";
		width = 5;
		align = "right";
		key = "conn";
		mapper = function(conn) return conn:serverport(); end;
	};
	dir = {
		title = "Dir";
		description = "Direction of server-to-server connection";
		width = 3;
		key = "direction";
		mapper = function(dir, session)
			if session.incoming and session.outgoing then return "<->"; end
			if dir == "outgoing" then return "-->"; end
			if dir == "incoming" then return "<--"; end
		end;
	};
	id = { title = "Session ID"; description = "Internal session ID used in logging"; width = 20; key = "id" };
	type = { title = "Type"; description = "Session type"; width = #"c2s_unauthed"; key = "type" };
	method = {
		title = "Method";
		description = "Connection method";
		width = 10;
		mapper = function(_, session)
			if session.bosh_version then
				return "BOSH";
			elseif session.websocket_request then
				return "WebSocket";
			else
				return "TCP";
			end
		end;
	};
	ipv = {
		title = "IPv";
		description = "Internet Protocol version (4 or 6)";
		width = 4;
		key = "ip";
		mapper = function(ip) if ip then return ip:find(":") and "IPv6" or "IPv4"; end end;
	};
	ip = { title = "IP address"; description = "IP address the session connected from"; width = 40; key = "ip" };
	status = {
		title = "Status";
		description = "Presence status";
		width = 6;
		key = "presence";
		mapper = function(p)
			if not p then return ""; end
			return p:get_child_text("show") or "online";
		end;
	};
	secure = {
		title = "Security";
		description = "TLS version or security status";
		key = "conn";
		width = 8;
		mapper = function(conn, session)
			if not session.secure then return "insecure"; end
			if not conn or not conn:ssl() then return "secure" end
			local sock = conn and conn:socket();
			if not sock then return "secure"; end
			local tls_info = sock.info and sock:info();
			return tls_info and tls_info.protocol or "secure";
		end;
	};
	encryption = {
		title = "Encryption";
		description = "Encryption algorithm used (TLS cipher suite)";
		width = 30;
		key = "conn";
		mapper = function(conn)
			local sock = conn:socket();
			local info = sock and sock.info and sock:info();
			if info then return info.cipher end
		end;
	};
	cert = {
		title = "Certificate";
		description = "Validation status of certificate";
		key = "cert_identity_status";
		width = 11;
		mapper = function(cert_status, session)
			if cert_status then return capitalize(cert_status); end
			if session.cert_chain_status == "Invalid" then
				local cert_errors = set.new(session.cert_chain_errors[1]);
				if cert_errors:contains("certificate has expired") then
					return "Expired";
				elseif cert_errors:contains("self signed certificate") then
					return "Self-signed";
				end
				return "Untrusted";
			elseif session.cert_identity_status == "invalid" then
				return "Mismatched";
			end
			return "Unknown";
		end;
	};
	sni = {
		title = "SNI";
		description = "Hostname requested in TLS";
		width = 22;
		mapper = function(_, session)
			if not session.conn then return end
			local sock = session.conn:socket();
			return sock and sock.getsniname and sock:getsniname() or "";
		end;
	};
	alpn = {
		title = "ALPN";
		description = "Protocol requested in TLS";
		width = 11;
		mapper = function(_, session)
			if not session.conn then return end
			local sock = session.conn:socket();
			return sock and sock.getalpn and sock:getalpn() or "";
		end;
	};
	smacks = {
		title = "SM";
		description = "Stream Management (XEP-0198) status";
		key = "smacks";
		width = 11;
		mapper = function(smacks_xmlns, session)
			if not smacks_xmlns then return "no"; end
			if session.hibernating then return "hibernating"; end
			return "yes";
		end;
	};
	smacks_queue = {
		title = "SM Queue";
		description = "Length of Stream Management stanza queue";
		key = "outgoing_stanza_queue";
		width = 8;
		align = "right";
		mapper = function (queue)
			return queue and tostring(queue:count_unacked());
		end
	};
	csi = {
		title = "CSI State";
		description = "Client State Indication (XEP-0352)";
		key = "state";
		-- TODO include counter
	};
	s2s_sasl = {
		title = "SASL";
		description = "Server authentication status";
		key = "external_auth";
		width = 10;
		mapper = capitalize
	};
	dialback = {
		title = "Dialback";
		description = "Legacy server verification";
		key = "dialback_key";
		width = 13;
		mapper = function (dialback_key, session)
			if not dialback_key then
				if session.type == "s2sin" or session.type == "s2sout" then
					return "Not used";
				end
				return "Not initiated";
			elseif session.type == "s2sin_unauthed" or session.type == "s2sout_unauthed" then
				return "Initiated";
			else
				return "Completed";
			end
		end
	};
};

local function get_colspec(colspec, default)
	if type(colspec) == "string" then colspec = array(colspec:gmatch("%S+")); end
	local columns = {};
	for i, col in pairs(colspec or default) do
		if type(col) == "string" then
			columns[i] = available_columns[col] or { title = capitalize(col); width = 20; key = col };
		elseif type(col) ~= "table" then
			return false, ("argument %d: expected string|table but got %s"):format(i, type(col));
		else
			columns[i] = col;
		end
	end

	return columns;
end

function def_env.c2s:show(match_jid, colspec)
	local print = self.session.print;
	local columns = get_colspec(colspec, { "id"; "jid"; "ipv"; "status"; "secure"; "smacks"; "csi" });
	local row = format_table(columns, 120);

	local function match(session)
		local jid = get_jid(session)
		return (not match_jid) or jid == match_jid;
	end

	local group_by_host = true;
	for _, col in ipairs(columns) do
		if col.key == "full_jid" or col.key == "host" then
			group_by_host = false;
			break
		end
	end

	if not group_by_host then print(row()); end
	local currenthost = nil;

	local c2s_sessions = get_c2s();
	local total_count = #c2s_sessions;
	c2s_sessions:filter(match):sort(_sort_by_jid);
	local shown_count = #c2s_sessions;
	for _, session in ipairs(c2s_sessions) do
		if group_by_host and session.host ~= currenthost then
			currenthost = session.host;
			print("#",prosody.hosts[currenthost] or "Unknown host");
			print(row());
		end

		print(row(session));
	end
	if total_count ~= shown_count then
		return true, ("%d out of %d c2s sessions shown"):format(shown_count, total_count);
	end
	return true, ("%d c2s sessions shown"):format(total_count);
end

function def_env.c2s:show_tls(match_jid)
	return self:show(match_jid, { "jid"; "id"; "secure"; "encryption" });
end

local function build_reason(text, condition)
	if text or condition then
		return {
			text = text,
			condition = condition or "undefined-condition",
		};
	end
end

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

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


def_env.s2s = {};
local function _sort_s2s(a, b)
	local a_local, a_remote = get_s2s_hosts(a);
	local b_local, b_remote = get_s2s_hosts(b);
	if (a_local or "") == (b_local or "") then return _sort_hosts(a_remote or "", b_remote or ""); end
	return _sort_hosts(a_local or "", b_local or "");
end

function def_env.s2s:show(match_jid, colspec)
	local print = self.session.print;
	local columns = get_colspec(colspec, { "id"; "host"; "dir"; "remote"; "ipv"; "secure"; "s2s_sasl"; "dialback" });
	local row = format_table(columns, 132);

	local function match(session)
		local host, remote = get_s2s_hosts(session);
		return not match_jid or host == match_jid or remote == match_jid;
	end

	local group_by_host = true;
	local currenthost = nil;
	for _, col in ipairs(columns) do
		if col.key == "host" then
			group_by_host = false;
			break
		end
	end

	if not group_by_host then print(row()); end

	local s2s_sessions = array(iterators.values(module:shared"/*/s2s/sessions"));
	local total_count = #s2s_sessions;
	s2s_sessions:filter(match):sort(_sort_s2s);
	local shown_count = #s2s_sessions;

	for _, session in ipairs(s2s_sessions) do
		if group_by_host and currenthost ~= get_s2s_hosts(session) then
			currenthost = get_s2s_hosts(session);
			print("#",prosody.hosts[currenthost] or "Unknown host");
			print(row());
		end

		print(row(session));
	end
	if total_count ~= shown_count then
		return true, ("%d out of %d s2s connections shown"):format(shown_count, total_count);
	end
	return true, ("%d s2s connections shown"):format(total_count);
end

function def_env.s2s:show_tls(match_jid)
	return self:show(match_jid, { "id"; "host"; "dir"; "remote"; "secure"; "encryption"; "cert" });
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, text, condition)
	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.id or (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, build_reason(text, condition));
			count = count + 1 ;
		end
	end
	return true, "Closed "..count.." s2s session"..((count == 1 and "") or "s");
end

function def_env.s2s:closeall(host, text, condition)
	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(build_reason(text, condition));
			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, _sort_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";

local function coerce_roles(roles)
	if roles == "admin" then roles = "prosody:admin"; end
	if type(roles) == "string" then roles = { [roles] = true }; end
	if roles[1] then for i, role in ipairs(roles) do roles[role], roles[i] = true, nil; end end
	return roles;
end

def_env.user = {};
function def_env.user:create(jid, password, roles)
	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
		if ok and roles then
			roles = coerce_roles(roles);
			local roles_ok, rerr = um.set_roles(jid, host, roles);
			if not roles_ok then return nil, "User created, but could not set roles: " .. tostring(rerr); end
		end
		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:showroles(jid, host)
	local username, userhost = jid_split(jid);
	if host == nil then host = userhost; end
	if host ~= "*" and not prosody.hosts[host] then
		return nil, "No such host: "..host;
	elseif prosody.hosts[userhost] and not um.user_exists(username, userhost) then
		return nil, "No such user";
	end
	local roles = um.get_roles(jid, host);
	if not roles then return true, "No roles"; end
	local count = 0;
	local print = self.session.print;
	for role in pairs(roles) do
		count = count + 1;
		print(role);
	end
	return true, count == 1 and "1 role" or count.." roles";
end

-- user:roles("someone@example.com", "example.com", {"prosody:admin"})
-- user:roles("someone@example.com", {"prosody:admin"})
function def_env.user:roles(jid, host, new_roles)
	local username, userhost = jid_split(jid);
	if new_roles == nil then host, new_roles = userhost, host; end
	if host ~= "*" and not prosody.hosts[host] then
		return nil, "No such host: "..host;
	elseif prosody.hosts[userhost] and not um.user_exists(username, userhost) then
		return nil, "No such user";
	end
	if host == "*" then host = nil; end
	return um.set_roles(jid, host, coerce_roles(new_roles));
end

-- TODO switch to table view, include roles
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 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 time_start = time.now();
	local print = self.session.print;
	local function onchange(what)
		return function(event)
			local s2s_session = event.session;
			if (s2s_session.from_host == localhost and s2s_session.to_host == remotehost)
				or (s2s_session.to_host == localhost and s2s_session.from_host == remotehost) then
				local dir = available_columns.dir.mapper(s2s_session.direction, s2s_session);
				print(("Session %s (%s%s%s) %s (%gs)"):format(s2s_session.id, localhost, dir, remotehost, what,
					time.now() - time_start));
			elseif s2s_session.type == "s2sin_unauthed" and s2s_session.to_host == nil and s2s_session.from_host == nil then
				print(("Session %s %s (%gs)"):format(s2s_session.id, what, time.now() - time_start));
			end
		end
	end
	local onconnected = onchange("connected");
	local onauthenticated = onchange("authenticated");
	local onestablished = onchange("established");
	local ondestroyed = onchange("destroyed");
	module:hook("s2s-connected", onconnected, 1);
	module:context(localhost):hook("s2s-authenticated", onauthenticated, 1);
	module:hook("s2sout-established", onestablished, 1);
	module:hook("s2sin-established", onestablished, 1);
	module:hook("s2s-destroyed", ondestroyed, 1);
	return module:context(localhost):send_iq(iq, nil, timeout):finally(function()
		module:unhook("s2s-connected", onconnected, 1);
		module:context(localhost):unhook("s2s-authenticated", onauthenticated);
		module:unhook("s2sout-established", onestablished);
		module:unhook("s2sin-established", onestablished);
		module:unhook("s2s-destroyed", ondestroyed);
	end):next(function(pong)
		return ("pong from %s in %gs"):format(pong.stanza.attr.from, time.now() - time_start);
	end);
end

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

local function get_resolver(session)
	local resolver = session.dns_resolver;
	if not resolver then
		resolver = adns.resolver();
		session.dns_resolver = resolver;
	end
	return resolver;
end

function def_env.dns:lookup(name, typ, class)
	local resolver = get_resolver(self.session);
	return resolver:lookup_promise(name, typ, class)
end

function def_env.dns:addnameserver(...)
	local resolver = get_resolver(self.session);
	resolver._resolver:addnameserver(...)
	return true
end

function def_env.dns:setnameserver(...)
	local resolver = get_resolver(self.session);
	resolver._resolver:setnameserver(...)
	return true
end

function def_env.dns:purge()
	local resolver = get_resolver(self.session);
	resolver._resolver:purge()
	return true
end

function def_env.dns:cache()
	local resolver = get_resolver(self.session);
	return true, "Cache:\n"..tostring(resolver._resolver.cache)
end

def_env.http = {};

function def_env.http:list(hosts)
	local print = self.session.print;
	hosts = array.collect(set.new({ not hosts and "*" or nil }) + get_hosts_set(hosts)):sort(_sort_hosts);
	local output = format_table({
			{ title = "Module", width = "20%" },
			{ title = "URL", width = "80%" },
		}, 132);

	for _, host in ipairs(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");
			if host == "*" then
				print("Global HTTP endpoints available on all hosts:");
			else
				print("HTTP endpoints on "..host..(http_host and (" (using "..http_host.."):") or ":"));
			end
			print(output());
			for _, provider in ipairs(http_apps) do
				local mod = provider._provided_by;
				local url = module:context(host):http_url(provider.name, provider.default_path);
				mod = mod and "mod_"..mod or ""
				print(output{mod, 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 print = self.session.print;
	local add_task = require"util.timer".add_task;
	local h, params = add_task.h, add_task.params;
	local function normalize_time(t)
		return t;
	end
	local function format_time(t)
		return os.date("%F %T", math.floor(normalize_time(t)));
	end
	if h then
		print("-- util.timer");
	elseif server.timer then
		print("-- net.server.timer");
		h = server.timer.add_task.timers;
		normalize_time = server.timer.to_absolute_time or normalize_time;
	end
	if h then
		local timers = {};
		for i, id in ipairs(h.ids) do
			local t, cb = h.priorities[i], h.items[id];
			if not params then
				local param = cb.param;
				if param then
					cb = param.callback;
				else
					cb = cb.timer_callback or cb;
				end
			elseif params[id] then
				cb = params[id].callback or cb;
			end
			table.insert(timers, { format_time(t), cb });
		end
		table.sort(timers, function (a, b) return a[1] < b[1] end);
		for _, t in ipairs(timers) do
			print(t[1], t[2])
		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, ("Next event at %s (in %.6fs)"):format(format_time(next_time), normalize_time(next_time) - time.now());
		end
	end
	return true;
end

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

def_env.stats = {};

local short_units = {
	seconds = "s",
	bytes = "B",
};

local stats_methods = {};

function stats_methods:render_single_fancy_histogram_ex(print, prefix, metric_family, metric, cumulative)
	local creation_timestamp, sum, count
	local buckets = {}
	local prev_bucket_count = 0
	for suffix, extra_labels, value in metric:iter_samples() do
		if suffix == "_created" then
			creation_timestamp = value
		elseif suffix == "_sum" then
			sum = value
		elseif suffix == "_count" then
			count = value
		elseif extra_labels then
			local bucket_threshold = extra_labels["le"]
			local bucket_count
			if cumulative then
				bucket_count = value
			else
				bucket_count = value - prev_bucket_count
				prev_bucket_count = value
			end
			if bucket_threshold == "+Inf" then
				t_insert(buckets, {threshold = 1/0, count = bucket_count})
			elseif bucket_threshold ~= nil then
				t_insert(buckets, {threshold = tonumber(bucket_threshold), count = bucket_count})
			end
		end
	end

	if #buckets == 0 or not creation_timestamp or not sum or not count then
		print("[no data or not a histogram]")
		return false
	end

	local graph_width, graph_height, wscale = #buckets, 10, 1;
	if graph_width < 8 then
		wscale = 8
	elseif graph_width < 16 then
		wscale = 4
	elseif graph_width < 32 then
		wscale = 2
	end
	local eighth_chars = "   ▁▂▃▄▅▆▇█";

	local max_bin_samples = 0
	for _, bucket in ipairs(buckets) do
		if bucket.count > max_bin_samples then
			max_bin_samples = bucket.count
		end
	end

	print("");
	print(prefix)
	print(("_"):rep(graph_width*wscale).." "..max_bin_samples);
	for row = graph_height, 1, -1 do
		local row_chars = {};
		local min_eighths, max_eighths = 8, 0;
		for i = 1, #buckets do
			local char_eighths = math.ceil(math.max(math.min((graph_height/(max_bin_samples/buckets[i].count))-(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] = ("-"):rep(wscale);
			else
				local char = eighth_chars:sub(char_eighths*3+1, char_eighths*3+3);
				row_chars[i] = char:rep(wscale);
			end
		end
		print(table.concat(row_chars).."|- "..string.format("%.8g", math.ceil((max_bin_samples/graph_height)*(row-0.5))));
	end

	local legend_pat = string.format("%%%d.%dg", wscale-1, wscale-1)
	local row = {}
	for i = 1, #buckets do
		local threshold = buckets[i].threshold
		t_insert(row, legend_pat:format(threshold))
	end
	t_insert(row, " " .. metric_family.unit)
	print(t_concat(row, "/"))

	return true
end

function stats_methods:render_single_fancy_histogram(print, prefix, metric_family, metric)
	return self:render_single_fancy_histogram_ex(print, prefix, metric_family, metric, false)
end

function stats_methods:render_single_fancy_histogram_cf(print, prefix, metric_family, metric)
	-- cf = cumulative frequency
	return self:render_single_fancy_histogram_ex(print, prefix, metric_family, metric, true)
end

function stats_methods:cfgraph()
	for _, stat_info in ipairs(self) do
		local family_name, metric_family = unpack(stat_info, 1, 2)
		local function print(s)
			table.insert(stat_info.output, s);
		end

		if not self:render_family(print, family_name, metric_family, self.render_single_fancy_histogram_cf) then
			return self
		end
	end
	return self;
end

function stats_methods:histogram()
	for _, stat_info in ipairs(self) do
		local family_name, metric_family = unpack(stat_info, 1, 2)
		local function print(s)
			table.insert(stat_info.output, s);
		end

		if not self:render_family(print, family_name, metric_family, self.render_single_fancy_histogram) then
			return self
		end
	end
	return self;
end

function stats_methods:render_single_counter(print, prefix, metric_family, metric)
	local created_timestamp, current_value
	for suffix, _, value in metric:iter_samples() do
		if suffix == "_created" then
			created_timestamp = value
		elseif suffix == "_total" then
			current_value = value
		end
	end
	if current_value and created_timestamp then
		local base_unit = short_units[metric_family.unit] or metric_family.unit
		local unit = base_unit .. "/s"
		local factor = 1
		if base_unit == "s" then
			-- be smart!
			unit = "%"
			factor = 100
		elseif base_unit == "" then
			unit = "events/s"
		end
		print(("%-50s %s"):format(prefix, format_number(factor * current_value / (self.now - created_timestamp), unit.." [avg]")));
	end
end

function stats_methods:render_single_gauge(print, prefix, metric_family, metric)
	local current_value
	for _, _, value in metric:iter_samples() do
		current_value = value
	end
	if current_value then
		local unit = short_units[metric_family.unit] or metric_family.unit
		print(("%-50s %s"):format(prefix, format_number(current_value, unit)));
	end
end

function stats_methods:render_single_summary(print, prefix, metric_family, metric)
	local sum, count
	for suffix, _, value in metric:iter_samples() do
		if suffix == "_sum" then
			sum = value
		elseif suffix == "_count" then
			count = value
		end
	end
	if sum and count then
		local unit = short_units[metric_family.unit] or metric_family.unit
		if count == 0 then
			print(("%-50s %s"):format(prefix, "no obs."));
		else
			print(("%-50s %s"):format(prefix, format_number(sum / count, unit.."/event [avg]")));
		end
	end
end

function stats_methods:render_family(print, family_name, metric_family, render_func)
	local labelkeys = metric_family.label_keys
	if #labelkeys > 0 then
		print(family_name)
		for labelset, metric in metric_family:iter_metrics() do
			local labels = {}
			for i, k in ipairs(labelkeys) do
				local v = labelset[i]
				t_insert(labels, ("%s=%s"):format(k, v))
			end
			local prefix = "  "..t_concat(labels, " ")
			render_func(self, print, prefix, metric_family, metric)
		end
	else
		for _, metric in metric_family:iter_metrics() do
			render_func(self, print, family_name, metric_family, metric)
		end
	end
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
			local metric_family = stat_info[2]
			if metric_family.type_ == "counter" then
				stats:render_family(print, stat_info[1], metric_family, stats.render_single_counter)
			elseif metric_family.type_ == "gauge" or metric_family.type_ == "unknown" then
				stats:render_family(print, stat_info[1], metric_family, stats.render_single_gauge)
			elseif metric_family.type_ == "summary" or metric_family.type_ == "histogram" then
				stats:render_family(print, stat_info[1], metric_family, stats.render_single_summary)
			end
		end
	end
	return #stats.." statistics displayed";
end

local stats_mt = {__index = stats_methods, __tostring = stats_tostring }
local function new_stats_context(self)
	-- TODO: instead of now(), it might be better to take the time of the last
	-- interval, if the statistics backend is set to use periodic collection
	-- Otherwise we get strange stuff like average cpu usage decreasing until
	-- the next sample and so on.
	return setmetatable({ session = self.session, stats = true, now = time.now() }, stats_mt);
end

function def_env.stats:show(name_filter)
	local statsman = require "core.statsmanager"
	local collect = statsman.collect
	if collect then
		-- force collection if in manual mode
		collect()
	end
	local metric_registry = statsman.get_metric_registry();
	local displayed_stats = new_stats_context(self);
	for family_name, metric_family in iterators.sorted_pairs(metric_registry:get_metric_families()) do
		if not name_filter or family_name:match(name_filter) then
			table.insert(displayed_stats, {
				family_name,
				metric_family,
				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