From: "F. Senault" <fred@...>
Date: 2009-03-30T18:05:01+09:00
Subject: Re: Symbols garbage collector in Ruby1.9, fixed?

Le 30 mars 2009 � 10:09, I�aki Baz Castillo a �crit :

> The problem is that I could receive custom headers so for each one a
> new Symbol would be created. An attacker could send lots of custom
> headers to fill the server memory and cause a denial of service.
> 
> Perhaps this is solved in Ruby 1.9? any suggestion on it? Thanks a lot.

It depends on what exactly you are trying to do with your hash.  If you
need to access to a few well known headers in your code, use symbols for
those and add another pseudo-header for the rest of the info :

USEFUL_HEADERS = [ :from, :to, :"x-mailer" ]

headers = {
  :from => "alice@aaa.com",
  :to => "bob@bbb.com",
  :"x-mailer" => "Pegasus Mail for Windows (4.50 PB1)",
  :"_custom" => {
    "x-custom-header-1" => "Hi there",
    "x-spam-scanned" => "Of course"
  }
}

(Now, you'll lose time at the parse step.  Again, depending on what
you're trying to do, it may be efficient if each mail is parsed one time
and, then, each header is accessed a lot of times.)

Fred
-- 
Well I'm the one without a soul   I'm the one with this big fucking hole
No new tale to tell  Twenty-six years on my way to hell  Gotta listen to
your big time hard line bad luck fist fuck     Don't think you're having
all the fun  You know me I hate everyone         (Nine Inch Nails, Wish)