Hello,
I've opened two merge requests on git.lysator.liu.se: one for new hash function support (https://git.lysator.liu.se/nettle/nettle/merge_requests/6) and another one for GOST 28147 cipher/MAC support (https://git.lysator.liu.se/nettle/nettle/merge_requests/7). Code has been tested for quite some time in GnuTLS and has been submitted with minor modifications.