On Tue, Feb 20, 2018 at 11:32:25AM +0000, Horia Geantă wrote:

If final/finup is optional, how is the final hash supposed to be retrieved?

Sometimes the computation ends with a partial hash, that's what
export is for.  Also it is completely legal to abandon the hash
state entirely.

According to documentation, these are the accepted flows (with the option to
export/import a partial hash b/w update and final/finup):

.init() -> .update() -> .final()
            ^    |         |
            '----'         '---> HASH

.init() -> .update() -> .finup()
            ^    |         |
            '----'         '---> HASH

           .digest()
               |
               '---------------> HASH

The documentation is simply incomplete in this regard.

Cheers,
-- 
Email: Herbert Xu [off-list ref]
Home Page: http://gondor.apana.org.au/~herbert/
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