const unsigned char *iv, const size_t ivlen,
unsigned char *shared_key);
/*============== miscellaneous functions============================= */
-/* from gost_sign.c */
-/* Convert GOST R 34.11 hash sum to bignum according to standard */
-BIGNUM *hashsum2bn(const unsigned char *dgst, int len);
/*
* Store bignum in byte array of given length, prepending by zeros if
* nesseccary