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Switch to a new role-based authorization framework, removing is_admin() We began moving away from simple "is this user an admin?" permission checks before 0.12, with the introduction of mod_authz_internal and the ability to dynamically change the roles of individual users. The approach in 0.12 still had various limitations however, and apart from the introduction of roles other than "admin" and the ability to pull that info from storage, not much actually changed. This new framework shakes things up a lot, though aims to maintain the same functionality and behaviour on the surface for a default Prosody configuration. That is, if you don't take advantage of any of the new features, you shouldn't notice any change. The biggest change visible to developers is that usermanager.is_admin() (and the auth provider is_admin() method) have been removed. Gone. Completely. Permission checks should now be performed using a new module API method: module:may(action_name, context) This method accepts an action name, followed by either a JID (string) or (preferably) a table containing 'origin'/'session' and 'stanza' fields (e.g. the standard object passed to most events). It will return true if the action should be permitted, or false/nil otherwise. Modules should no longer perform permission checks based on the role name. E.g. a lot of code previously checked if the user's role was prosody:admin before permitting some action. Since many roles might now exist with similar permissions, and the permissions of prosody:admin may be redefined dynamically, it is no longer suitable to use this method for permission checks. Use module:may(). If you start an action name with ':' (recommended) then the current module's name will automatically be used as a prefix. To define a new permission, use the new module API: module:default_permission(role_name, action_name) module:default_permissions(role_name, { action_name[, action_name...] }) This grants the specified role permission to execute the named action(s) by default. This may be overridden via other mechanisms external to your module. The built-in roles that developers should use are: - prosody:user (normal user) - prosody:admin (host admin) - prosody:operator (global admin) The new prosody:operator role is intended for server-wide actions (such as shutting down Prosody). Finally, all usage of is_admin() in modules has been fixed by this commit. Some of these changes were trickier than others, but no change is expected to break existing deployments. EXCEPT: mod_auth_ldap no longer supports the ldap_admin_filter option. It's very possible nobody is using this, but if someone is then we can later update it to pull roles from LDAP somehow.

local st = require "util.stanza";
local lxp = require "lxp";
local t_insert = table.insert;
local t_remove = table.remove;
local error = error;

local _ENV = nil;
-- luacheck: std none

local parse_xml = (function()
	local ns_prefixes = {
		["http://www.w3.org/XML/1998/namespace"] = "xml";
	};
	local ns_separator = "\1";
	local ns_pattern = "^([^"..ns_separator.."]*)"..ns_separator.."?(.*)$";
	return function(xml, options)
		--luacheck: ignore 212/self
		local handler = {};
		local stanza = st.stanza("root");
		local namespaces = {};
		local prefixes = {};
		function handler:StartNamespaceDecl(prefix, url)
			if prefix ~= nil then
				t_insert(namespaces, url);
				t_insert(prefixes, prefix);
			end
		end
		function handler:EndNamespaceDecl(prefix)
			if prefix ~= nil then
				-- we depend on each StartNamespaceDecl having a paired EndNamespaceDecl
				t_remove(namespaces);
				t_remove(prefixes);
			end
		end
		function handler:StartElement(tagname, attr)
			local curr_ns,name = tagname:match(ns_pattern);
			if name == "" then
				curr_ns, name = "", curr_ns;
			end
			if curr_ns ~= "" then
				attr.xmlns = curr_ns;
			end
			for i=1,#attr do
				local k = attr[i];
				attr[i] = nil;
				local ns, nm = k:match(ns_pattern);
				if nm ~= "" then
					ns = ns_prefixes[ns];
					if ns then
						attr[ns..":"..nm] = attr[k];
						attr[k] = nil;
					end
				end
			end
			local n = {}
			for i=1,#namespaces do
				n[prefixes[i]] = namespaces[i];
			end
			stanza:tag(name, attr, n);
		end
		function handler:CharacterData(data)
			stanza:text(data);
		end
		function handler:EndElement()
			stanza:up();
		end
		-- SECURITY: These two handlers, especially the Doctype one, are required to prevent exploits such as Billion Laughs.
		local function restricted_handler(parser)
			if not parser.stop or not parser:stop() then
				error("Failed to abort parsing");
			end
		end
		handler.StartDoctypeDecl = restricted_handler;
		if not options or not options.allow_comments then
			-- NOTE: comments are generally harmless and can be useful when parsing configuration files or other data, even user-provided data
			handler.Comment = restricted_handler;
		end
		if not options or not options.allow_processing_instructions then
			-- Processing instructions should generally be safe to just ignore
			handler.ProcessingInstruction = restricted_handler;
		end
		local parser = lxp.new(handler, ns_separator);
		local ok, err, line, col = parser:parse(xml);
		if ok then ok, err, line, col = parser:parse(); end
		--parser:close();
		if ok then
			return stanza.tags[1];
		else
			return ok, ("%s (line %d, col %d))"):format(err, line, col);
		end
	end;
end)();

return {
	parse = parse_xml;
};