some questions on OpenSSH alogs

Christian Weisgerber naddy at
Mon Oct 20 00:37:51 EST 2014

On 2014-10-18, Christian Weisgerber <naddy at> wrote:

> You'll also find that OpenSSH 6.6 has already trimmed the list of
> default algorithms.

That's actually OpenSSH 6.7.

>> 7) I found however, that UMAC is optimised for 32bit architectures...
>> are there any plans to integrate a VMAC algo?
> I considered it, but decided I didn't want to further expand the
> algorithm zoo we already have.

This tickled some half-buried memory and made me look again.  VMAC's
core operation is a 64 by 64 to 128 bits multiplication.  This can't
be expressed in portable C and even if you resort to inline assembly,
not all 64-bit archs may support this operation.  (E.g., I don't
see a corresponding instruction in the SPARCv9 manual.)

Christian "naddy" Weisgerber                          naddy at

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