add validation of topics and protected topic mode

lib/server/connection.ml

@@ -68,11 +68,27 @@ let modeunknownflag       = "501", ["Didn't understand MODE command"]
 let usersdontmatch_set    = "502", ["Can't change mode for other users"]
 let usersdontmatch_get    = "502", ["Can't view mode for other users"]
 
+
+(* permission checking *)
+
 let require_registered t : User.t result =
   match t.user with
   | Some me -> Ok me
   | None -> Error notregistered
 
+let require_same_user user me =
+  if (user : User.t) == me then Ok () else Error usersdontmatch_get
+
+let require_membership chan me =
+  match Router.membership chan me with
+  | mem -> Ok mem
+  | exception Not_found -> Error (notonchannel (Chan.name chan))
+
+let require_chan_op (m : Router.membership) =
+  match m.mem_priv with
+  | Operator -> Ok ()
+  | _ -> Error (chanoprivsneeded (Chan.name m.mem_chan))
+
 
 (* modes *)
 
@@ -139,14 +155,6 @@ let set_member_priv ~from (mem : Router.membership) (priv : Router.priv) =
     Router.relay msg ~from [`to_chan chan; `to_self];
     mem.mem_priv <- priv
 
-let require_same_user user me =
-  if (user : User.t) == me then Ok () else Error usersdontmatch_get
-
-let require_chan_op chan me =
-  match Router.membership chan me with
-  | m when m.mem_priv = Operator -> Ok (* m *) ()
-  | _ | exception Not_found -> Error (chanoprivsneeded (Chan.name chan))
-
 let on_get_user_mode user me =
   let* () = require_same_user user me in
   Ok [
@@ -189,8 +197,6 @@ let on_get_chan_mode chan me =
   Ok (List.flatten rpls)
 
 let on_set_chan_mode chan me modestr args ~router =
-  let* () = require_chan_op chan me in
-
   let* chg = try Ok (Mode.Parse.chan_modes modestr args)
     with Mode.Parse.Error ->
       (* TODO: ERR_INVALIDMODEPARAM (696)
@@ -201,6 +207,9 @@ let on_set_chan_mode chan me modestr args ~router =
       Error modeunknownflag
   in
 
+  let* mem = require_membership chan me in
+  let* () = require_chan_op mem in
+
   set_chan_mode chan ~from:me ~add:chg.chan_modes.add ~rem:chg.chan_modes.rem;
   Option.iter (set_chan_key chan ~from:me) chg.chan_key;
   Option.iter (set_chan_limit chan ~from:me) chg.chan_limit;
@@ -358,15 +367,16 @@ let on_msg_topic t name args =
     with Not_found ->
       Error (nosuchchannel name)
   in
+  let* mem = require_membership chan me in
   match args with
   | [] ->
-    (* TODO: if +s then don't send topic to non-members *)
-    _todo_validation_please ();
     get_topic t chan;
     Ok ()
   | args ->
-    (* TODO: if +t then only allow +o to set topic *)
-    _todo_validation_please ();
+    let* () =
+      if Mode.Set.mem `t (Chan.mode chan) then require_chan_op mem
+      else Ok ()
+    in
     let topic = String.concat " " args in
     let msg = Msg.make "TOPIC" [Chan.name chan; topic] ~always_trailing:true in
     Router.relay msg ~from:me [`to_chan chan; `to_self];
@@ -403,7 +413,7 @@ let on_msg_join t name =
   | exception Not_found ->
     begin
       (* TODO: +k *)
-      (* TODO: +l *)
+      (* TODO: check chan user limit (+l) *)
       _todo_validation_please ();
       join t me chan;
       get_topic t chan ~reply_if_missing:false;