Less restrictive anti-bandwidth-theft code. Fixes a problem

[cocanwiki.git] / scripts / image.ml

diff --git a/scripts/image.ml b/scripts/image.ml
index 4484546..cad2ceb 100644 (file)
--- a/scripts/image.ml
+++ b/scripts/image.ml
@@ -1,7 +1,7 @@
 (* COCANWIKI - a wiki written in Objective CAML.
  * Written by Richard W.M. Jones <rich@merjis.com>.
  * Copyright (C) 2004 Merjis Ltd.
- * $Id: image.ml,v 1.5 2004/09/09 12:21:22 rich Exp $
+ * $Id: image.ml,v 1.13 2004/11/01 16:24:32 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
@@ -24,9 +24,11 @@ open Registry
 open Cgi
 open Printf
 
+open ExtString
+
 open Cocanwiki
 
-let run r (q : cgi) (dbh : Dbi.connection) hostid _ _ =
+let run r (q : cgi) (dbh : Dbi.connection) hostid {hostname = hostname} _ =
   let image = q#param "image" in
   let is_thumbnail = q#param_true "thumbnail" in
   let version =
@@ -34,8 +36,8 @@ let run r (q : cgi) (dbh : Dbi.connection) hostid _ _ =
 
   (* Get the image and its MIME type. *)
   let what =
-    if not is_thumbnail then "image, mime_type"
-    else "thumbnail, tn_mime_type" in
+    if not is_thumbnail then "image, mime_type, name is null as deleted"
+    else "thumbnail, tn_mime_type, name is null as deleted" in
   let where, args =
     match version with
        None -> "hostid = ? and name = ?", [`Int hostid; `String image]
@@ -47,18 +49,38 @@ let run r (q : cgi) (dbh : Dbi.connection) hostid _ _ =
              ("select " ^ what ^ " from images where " ^ where) in
   sth#execute args;
 
-  let data, mime_type =
-    match sth#fetch1 () with
-       [ `Binary data; `String mime_type ] ->
-         data, mime_type
-      | _ -> assert false in
+  let data, mime_type, deleted =
+    try
+      (match sth#fetch1 () with
+          [ `Binary data; `String mime_type; `Bool deleted ] ->
+            data, mime_type, deleted
+        | _ -> assert false)
+    with
+       Not_found -> raise (HttpError cHTTP_NOT_FOUND) in
+
+  (* If deleted, refuse to serve this image except if shown on the site. *)
+  if deleted then (
+    let referer =
+      try Table.get (Request.headers_in r) "Referer" with Not_found -> "" in
+    let ok =
+      try String.find referer hostname; true
+      with String.Invalid_string -> false in
+
+    if not ok then (
+      prerr_endline "image.ml: bandwidth theft avoided";
+      raise (HttpError cHTTP_NOT_FOUND)
+    )
+  );
+
+  (* Set a medium-length expiry time on this resource. *)
+  Table.set (Request.headers_out r) "Expires" (Expires.medium ());
 
-  if version <> None then
-    (* Set a medium-length expiry time on this resource. *)
-    Table.set (Request.headers_out r) "Expires" (Cgi_expires.expires_medium());
+  (* Content-length header. *)
+  Table.set (Request.headers_out r) "Content-Length"
+    (string_of_int (String.length data));
 
   q#header ~content_type:mime_type ();
-  print_string r data
+  ignore (print_string r data)
 
 let () =
-  register_script run
+  register_script ~restrict:[CanView] run