pkcs5_pbkdf2
if (pkcs5_pbkdf2(&tmp, BITS2BYTES(keylen), (uint8_t *)passp,
ret = pkcs5_pbkdf2(&r, dkLen, P, sizeof(P), S, sizeof(S), c, 0);
int pkcs5_pbkdf2(u_int8_t **, size_t, const u_int8_t *, size_t,