void silc_rng_init(SilcRng rng);

    This function is used to initialize the random number generator.
    This is the function that must be called after the RNG is allocated
    by calling silc_rng_alloc.  RNG cannot be used before this function
    is called.

    This function may be slow since it will acquire secret noise from
    the environment in an attempt to set the RNG in unguessable state.