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 test6: DRBG_check "b512633f27fb182a076917e39888ba3ff35d23c3742eb8f3c635a044163768e0"%string "e2c39b84629a3de5c301db5643af1c21" "4038798b0b8bfc7be148adbdeacaf082155c46bbc86538d574aaeb0f187c52fc"%string "e46a05a9268ecc00ecc3310947baa11d1ccd42cedd0ed80d78b6fb43bfd1b903"%string "" [ ("5464d1f719fff5cda06a0ee358b18b8a9d8dfa3525d461f343f1a3be5138fa9a"%string, "759926760ecbb5c000992227f1065c18cbff9a5aaec38911d6e7a399bab4783b"%string, ""%string); ("df2103bf3d5dd0d60870042d702478272caef5198ff71441a772d705f28ee760"%string, "cad9c856f921f6a248e0db4b3356e06e205fd9a15980030e1d32a303f4278329"%string, ""%string) ] "fb931d0d0194a97b48d5d4c231fdad5c61aedf1c3a55ac24983ecbf38487b1c93396c6b86ff3920cfa8c77e0146de835ea5809676e702dee6a78100da9aa43d8ec0bf5720befa71f82193205ac2ea403e8d7e0e6270b366dc4200be26afd9f63b7e79286a35c688c57cbff55ac747d4c28bb80a2b2097b3b62ea439950d75dff"%string.