Function nginx::RSA_meth_set_bn_mod_exp

pub unsafe extern "C" fn RSA_meth_set_bn_mod_exp(
    rsa: *mut RSA_METHOD, 
    bn_mod_exp: Option<unsafe extern "C" fn(r: *mut BIGNUM, a: *const BIGNUM, p: *const BIGNUM, m: *const BIGNUM, ctx: *mut BN_CTX, m_ctx: *mut BN_MONT_CTX) -> c_int>
) -> c_int