[openssl-users] BN_MUL_MONT for ARM64 v8

[Matt Caswell]

On 08/02/17 14:12, Michael Wojcik wrote:
>> From: openssl-users [mailto:openssl-users-bounces at openssl.org] On
>> Behalf Of Mike Mohr Sent: Tuesday, February 07, 2017 22:21
> 
>> Licensing issues are indeed thorny. Why can't openssl perform a
>> dynamic link? The soversion should handle any ABI issues introduced
>> in later versions of GMP.
> 
> Replace "thorny" with "completely unacceptable" for at least some
> commercial users of  OpenSSL. And dynamic linking does not solve the
> problem, because customers would still have to get GMP. Some
> companies refuse to ship GPL code in any form, regardless of whether
> they've made modifications, and forcing customers to find and install
> GMP is hardly reasonable.
> 
> Providing TLS support in commercial software is already difficult
> enough. Let's not make it harder in the hypothetical hope of eking
> out a bit more performance.
> 
> Anyone who really wants GMP could implement it as an OpenSSL engine.
> That is, take the OpenSSL code for the algorithms you're using, copy
> them into an  engine, and then replace the BN math operations with
> calls to GMP.

FYI, there already *is* a GMP engine in 1.0.2. It got removed from 1.1.0
due to lack of use. It is not compiled by default. You have to use
"enable-gmp". Not tried it though.

Matt