Source file vdf.ml

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module type Vdf_sig = sig
  module Group : S.GROUP

  (** [prove_vdf discriminant form difficulty] *)
  val prove : Group.t -> Unsigned.UInt64.t -> Group.t * Group.t

  (** [verify_vdf discriminant form difficulty form form] *)
  val verify : Group.t -> Unsigned.UInt64.t -> Group.t -> Group.t -> bool
end

module Stubs = struct
  external prove :
    Bytes.t ->
    Unsigned.Size_t.t ->
    Bytes.t ->
    Unsigned.UInt64.t ->
    Bytes.t ->
    Bytes.t ->
    unit = "caml_prove_bytecode_stubs" "caml_prove_stubs"

  external verify :
    Bytes.t ->
    Unsigned.Size_t.t ->
    Bytes.t ->
    Bytes.t ->
    Bytes.t ->
    Unsigned.UInt64.t ->
    bool = "caml_verify_bytecode_stubs" "caml_verify_stubs"
end

module Make (CG : Class_group.Class_group_sig) : Vdf_sig = struct
  module Group = CG

  let discriminant_bytes = Utils.Integer.to_bytes CG.discriminant

  let prove challenge difficulty =
    let challenge_bytes = CG.to_bytes challenge in
    let result_bytes = Bytes.create CG.size_in_bytes in
    let proof_bytes = Bytes.create CG.size_in_bytes in
    Stubs.prove
      discriminant_bytes
      CG.discriminant_size
      challenge_bytes
      difficulty
      result_bytes
      proof_bytes ;
    let result = CG.of_bytes_exn result_bytes in
    let proof = CG.of_bytes_exn proof_bytes in
    (result, proof)

  let verify challenge difficulty result proof =
    let challenge_bytes = CG.to_bytes challenge in
    let result_bytes = CG.to_bytes result in
    let proof_bytes = CG.to_bytes proof in
    Stubs.verify
      discriminant_bytes
      CG.discriminant_size
      challenge_bytes
      result_bytes
      proof_bytes
      difficulty
end