Handling over sized keys on OpenSSL

  106827
September 1, 2019 03:33 lc@leocavalcante.com (Leo Cavalcante)
Hi Internals,
I just spent this entire Saturday debugging a code to discover that OpenSSL
truncates over sized keys.
Yeah, I was using a 256-bit length key with AES-128-CBC then trying to
decrypt it in another program never works.
Did some research I found that Ruby did it a few years ago
<https://github.com/ruby/ruby/commit/ce635262f53b760284d56bb1027baebaaec175d1?fbclid=IwAR2W3mJEljXwedq4VkhWjkXO0fsiEliORsuPSN2YqOAhkZk1fGfC3CqkPaU>
..
And in fact, its better to throw or even warn/notice about it instead of
silently allowing it, *what you think?*
Regards,
Leo
  107228
September 19, 2019 01:59 bishop@php.net (Bishop Bettini)
On Sat, Aug 31, 2019 at 11:34 PM Leo Cavalcante <lc@leocavalcante.com>
wrote:

> ... > Yeah, I was using a 256-bit length key with AES-128-CBC then trying to > decrypt it in another program never works. > > And in fact, its better to throw or even warn/notice about it instead of > silently allowing it, *what you think?* >
I can't imagine a legitimate scenario necessitating too much, or too little, key bits. So, I think this is throw-worthy, perhaps a \RangeException. This isn't my area of expertise though -- so I'm copying Sara who, if memory serves, has recently been dealing with crypto. See also Bug #72247[1]. [1]:https://bugs.php.net/bug.php?id=72247