I don't think that will work. The SSL code uses in-place buffers extensively, so in == out definitely needs to be defined. The question is only whether out < in is also acceptable.
Either way, for BoringSSL, I've gone ahead and tightened our aliasing constraints to forbid out < in and require equality, so that we don't have to keep chasing down discrepancies in the assembly code in advance of a decision being made here. (I think there is something to be said for being able to in-place-ish decrypt a structure with a record header and write the output without the header, but perhaps this use case is not worth the cost---I see the numbers went down slightly for chacha-x86.pl. Then again, most other files manage it naturally. It's a decision you all will need to make.) David On Wed, Jun 15, 2016 at 11:01 AM Rich Salz via RT <r...@openssl.org> wrote: > I think for now, we just note this in the documentation: behavior for > overlapping buffers, and even in-place buffers, is not defined. > > It's like memcpy() vs memmove(). > > -- > Ticket here: http://rt.openssl.org/Ticket/Display.html?id=4362 > Please log in as guest with password guest if prompted > > -- Ticket here: http://rt.openssl.org/Ticket/Display.html?id=4362 Please log in as guest with password guest if prompted -- openssl-dev mailing list To unsubscribe: https://mta.openssl.org/mailman/listinfo/openssl-dev
