Definition stream_dummy (result: string) (n: nat) : option bool :=
  let hex := bytesToBits (hexstring_to_Zlist result) in
  if nth_ok n hex false then Some (nth n hex false)
  else None.Definition get_nonce_dummy (result: string) (_: unit) := hexstring_to_Zlist result.Definition noop_reseed_function (s: ENTROPY.stream) (x: DRBG_state_handle) (_: bool) (_: list Z) := ENTROPY.success x s.Fixpoint DRBG_generate_check (state_handle: DRBG_state_handle) (internal_states: list (string * string * string)) (returned_bits: string) :=
  let test_HMAC256_DRBG_generate_function := HMAC256_DRBG_generate_function noop_reseed_function 1024 128 128 in
  match internal_states with
    | [] => True
    | (key, v, additional_input)::[] =>
      let key := hexstring_to_Zlist key in
      let value := hexstring_to_Zlist v in
      let additional_input := hexstring_to_Zlist additional_input in
      let returned_bits := hexstring_to_Zlist returned_bits in
      match test_HMAC256_DRBG_generate_function (stream_dummy "") state_handle 128 256 false additional_input with
        | ENTROPY.success (returned_bits', ((value', key', _), _, _)) _ => listZ_eq value value' = true /\ listZ_eq key key' = true /\ listZ_eq returned_bits returned_bits' = true
        | ENTROPY.error _ _ => False
      end
    | (key, v, additional_input)::tl =>
      let key := hexstring_to_Zlist key in
      let value := hexstring_to_Zlist v in
      let additional_input := hexstring_to_Zlist additional_input in
      match test_HMAC256_DRBG_generate_function (stream_dummy "") state_handle 128 256 false additional_input with
        | ENTROPY.success (_, ((value', key', x), y, z)) _ => listZ_eq value value' = true /\ listZ_eq key key' = true /\ DRBG_generate_check ((value', key', x), y, z) tl returned_bits
        | ENTROPY.error _ _ => False
      end
  end.Definition DRBG_check (entropy_input nonce key value personalization_string: string) (internal_states: list (string * string * string)) (returned_bits: string) :=
  let key := hexstring_to_Zlist key in
  let value := hexstring_to_Zlist value in
  let personalization_string := hexstring_to_Zlist personalization_string in
  match HMAC256_DRBG_instantiate_function 32 32 (get_nonce_dummy nonce) 256 256 false (stream_dummy entropy_input) 256 false personalization_string with
    | ENTROPY.success ((value', key', x), y, z) _ => listZ_eq value value' = true /\ listZ_eq key key' = true /\ DRBG_generate_check ((value', key', x), y, z) internal_states returned_bits
    | _ => False
  end.

Lemma test2: DRBG_check "b340907445b97a8b589264de4a17c0bea11bb53ad72f9f33297f05d2879d898d"%string "65cb27735d83c0708f72684ea58f7ee5" "f35c29e8db08c1b947ad0263cf3dbe735d74abb99c021728c3c9235a7cdb0bbf"%string "0b8e71f560cbe2b358684fc682ba7837480017785266d698a49c0bdf02a65eda"%string "" [ ("f943ed975c2013dbc9dc1025d7c3ebaa463bc1e4368df1c04348677e5148c9b7"%string, "6a66c83034d1f48cfc9fa7708c643792e790e9a25ed0e2f479f481d833343366"%string, ""%string); ("6b1e253f4cfd379ce55e9659dc97fe7c24f07ee54648807a2f72c5faf2dd1d35"%string, "d508c96ba979c61a2034d1f6335fe7e967da7fec6752d0cb09de2530eca537d3"%string, ""%string) ] "75183aaaf3574bc68003352ad655d0e9ce9dd17552723b47fab0e84ef903694a32987eeddbdc48efd24195dbdac8a46ba2d972f5808f23a869e71343140361f58b243e62722088fe10a98e43372d252b144e00c89c215a76a121734bdc485486f65c0b16b8963524a3a70e6f38f169c12f6cbdd169dd48fe4421a235847a23ff"%string.