[openssl-dev] Removing obsolete crypto from OpenSSL 1.1 - seeking feedback

[Viktor Dukhovni]

On Sat, Nov 14, 2015 at 07:32:33AM +0000, Peter Waltenberg wrote:

>    I also can't see any point expunging old algorithms from the sources,
>    making them not build by default should be enough.

It is difficult enough to maintain code that is typically built,
dead code is even harder to keep correct.  And what are distributions
of the library to do?  Break a lot of customer code by shipping
with the algorithms disabled?  Or re-enable compilation?

>    The only thing I would suggest is dropping assembler support for
>    anything that's been retired, just to cut the maintenance effort / risk
>    of breakage. If it's legacy only, performance shouldn't be an issue.

That probably makes more sense.  Drop associated SSL/TLS ciphersuite
codepoints and drop assembly support (if any).  Leave the C
implementation in libcrypto to support legacy "data at rest"
applications.

The proposed list was:

    CAST
    IDEA
    MDC2
    MD2 [ already disabled by default ]
    RC5 [ already disabled by default ]
    RIPEMD
    SEED
    WHIRLPOOL
    ALL BINARY ELLIPTIC CURVES

If I were to guess, it would be that the base crypto implementations
of IDEA, SEED and binary elliptic curves need to stay.  We could
perhaps get away with removing CAST and RIPEMD.  No idea about the
rest.

-- 
	Viktor.