(* COCANWIKI - a wiki written in Objective CAML. * Written by Richard W.M. Jones . * Copyright (C) 2004 Merjis Ltd. * $Id: cocanwiki.ml,v 1.11 2004/09/23 11:56:47 rich Exp $ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. *) open Apache open Registry open Cgi open Printf open Cocanwiki_ok open Cocanwiki_strings module Pool = DbiPool (Dbi_postgres) (* This function is used to grab a database handle. It's used in a couple * of very special places, and is not for general consumption. *) let _get_dbh r = Pool.get r "cocanwiki" (* Server-wide settings. * * These are stored in a single row in the database in the table * 'server_settings'. You must restart the server if you change * this row. * * It's not possible to read these at server start-up time because the * Apache server is still running as 'root' and will not normally be * allowed to access the database. We thus read them at the earliest * opportunity, in a request context, and cache the results. *) let server_settings_version = let settings = ref None in let get_settings (dbh : Dbi.connection) = let sth = dbh#prepare "select version from server_settings" in sth#execute []; let s = match sth#fetch1 () with | [ `Int version ] -> version | _ -> assert false in sth#finish (); settings := Some s; s in let server_settings_version dbh = let (version) = match !settings with None -> get_settings dbh | Some settings -> settings in version in server_settings_version (* The [CgiExit] exception should be folded back into the base * mod_caml code at some point. It just causes the 'run' function to * return at that point safely. (XXX) *) exception CgiExit let return () = raise CgiExit (* Permissions and restrictions. * * Use the optional ~restrict parameter to register_script to restrict * who can use the script. For example: * register_script ~restrict:[CanEdit ; CanManageUsers] run *) type permissions_t = CanEdit | CanManageUsers | CanManageContacts | CanManageSite | CanEditGlobalCSS (* The "user object". *) type user_t = Anonymous (* Not logged in. *) | User of int * string * permissions_t list (* Userid, name, permissions. *) let test_permission edit_anon perm user = if perm = CanEdit && edit_anon then true else match user with Anonymous -> false | User (_, _, perms) -> List.mem perm perms let can_edit edit_anon = test_permission edit_anon CanEdit let can_manage_users = test_permission false CanManageUsers let can_manage_contacts = test_permission false CanManageContacts let can_manage_site = test_permission false CanManageSite let can_edit_global_css = test_permission false CanEditGlobalCSS (* The "host object". *) type host_t = { hostname : string; edit_anon : bool; } (* Our wrapper around the standard [register_script] function. * * The optional ~restrict and ~anonymous parameters work as follows: * * By default (neither parameter given), anonymous or logged-in users * at any level are permitted to run the script. * * If ~anonymous:false then a user must be logged in to use the script. * * If ~restrict contains a list of permissions (eg. CanEdit, etc.) then * the user must have the ability to do AT LEAST ONE of those actions. * (Note that this does not necessarily imply that the user must be * logged in, because in some circumstances even anonymous users have * the CanEdit permission - very typical for a wiki). * * If ~anonymous:false and ~restrict is given then the user must be * logged in AND have the ability to do AT LEAST ONE of those actions. *) let register_script ?(restrict = []) ?(anonymous = true) run = (* Actually register the script with the real [Registry] module. *) register_script (fun r -> let q = new cgi r in let dbh = _get_dbh r in (* Get the host ID, by comparing the Host: header with the hostnames * table in the database. *) let hostid, hostname, edit_anon = let hostname = try Request.hostname r with Not_found -> failwith "No ``Host:'' header in request" in let hostname = String.lowercase hostname in let sth = dbh#prepare_cached "select h.id, h.canonical_hostname, h.edit_anon from hostnames hn, hosts h where hn.name = ? and hn.hostid = h.id" in sth#execute [`String hostname]; try (match sth#fetch1 () with [ `Int id; `String hostname; `Bool edit_anon ] -> id, hostname, edit_anon | _ -> assert false) with Not_found -> failwith ("Hostname ``" ^ hostname ^ "'' not found in " ^ "the hosts/hostnames tables in the database.") in (* Create the host object. *) let host = { hostname = hostname; edit_anon = edit_anon; } in (* Look for the user's cookie, and determine from this the user * object. *) let user = try let cookie = (* Allow the user to deliberately specify an extra "cookie" * parameter, which we will send back as a cookie. This is * useful for "mail my password"-type scripts. *) if q#param_exists "cookie" then ( let value = q#param "cookie" in let cookie = Cookie.cookie ~name:"auth" ~value ~path:"/" () in Table.set (Request.headers_out r) "Set-Cookie" cookie#as_string; value ) else ( (* Normal cookie, from the headers. *) let header = Table.get (Request.headers_in r) "Cookie" in let cookies = Cookie.parse header in let cookie = List.find (fun cookie -> cookie#name = "auth") cookies in cookie#value ) in let sth = dbh#prepare_cached "select u.id, u.name, u.can_edit, u.can_manage_users, u.can_manage_contacts, u.can_manage_site, u.can_edit_global_css from usercookies uc, users u where uc.cookie = ? and uc.userid = u.id and u.hostid = ?" in sth#execute [`String cookie; `Int hostid]; (match sth#fetch1 () with [ `Int userid; `String name; `Bool can_edit; `Bool can_manage_users; `Bool can_manage_contacts; `Bool can_manage_site; `Bool can_edit_global_css ] -> let perms = if can_edit then [ CanEdit ] else [] in let perms = if can_manage_users then CanManageUsers :: perms else perms in let perms = if can_manage_contacts then CanManageContacts :: perms else perms in let perms = if can_manage_site then CanManageSite :: perms else perms in let perms = if can_edit_global_css then CanEditGlobalCSS :: perms else perms in User (userid, name, perms) | _ -> assert false) with Not_found -> Anonymous in (* If the ~restrict parameter is given, then we want to check that * the user has sufficient permission to run this script. *) let permitted = if not anonymous && user = Anonymous then false else match restrict with [] -> true (* empty list = no restrictions *) | rs -> List.fold_left (||) false (List.map (fun r -> test_permission edit_anon r user) rs) in if permitted then ( (* Call the actual CGI script. *) try run r q dbh hostid host user with CgiExit -> () ) else error ~back_button:true ~title:"Access denied" q "You do not have permission to access this part of the site." ) (* Convert a section name into something valid for use in * XXX This breaks horribly for non-7-bit strings. * XXX This is stuck here because we don't have a good place for it, and * because it needs to be fixed for i18n compliance. *) let linkname_of_sectionname str = let str = String.copy str in for i = 0 to String.length str - 1 do if not (isalnum str.[i]) then str.[i] <- '_' done; str