package octez-libs

  1. Overview
  2. Docs
package octez-libs
Legend:
Page
Library
Module
Module type
Parameter
Class
Class type
Source

Source file identities.ml

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
open Kzg.Bls
module SMap = Kzg.SMap

(* Module to operate with polynomials in FFT evaluations form. *)
module Evaluations = Evaluations_map.Make (Evals)

module Identities : sig
  (** The type for prover identities: functions from a (string) map of
      polynomials in FFT evaluations form to a (string) map of evaluated
      identities (also polynomials in FFT evaluations form). *)
  type prover_identities = Evaluations.t SMap.t -> Evaluations.t SMap.t

  (** The type for verifier identities: functions which map an evaluation point
      ξ an a [PC.answer] into a (string) map of evaluated identities. *)
  type verifier_identities =
    Scalar.t -> Scalar.t SMap.t SMap.t -> Scalar.t SMap.t

  (** The type for evaluation points. Either [X], [GX], or a custom point,
        which must be specified by an evaluation point name paired with a
        scalar that will multiply ξ. For example:
          - [X] could be implemented as [Custom ("x", Scalar.one)]
          - [GX] could be implemented as
            [Custom ("gx", generator)]. *)
  type eval_point = X | GX | Custom of string * Scalar.t [@@deriving repr]

  val string_of_eval_point : eval_point -> string

  (** [convert_eval_points gen x points] maps the polynomial protocol
               [points : eval_point list] into scalars, by evaluating the underlying
               "composition" polynomial at [x].
               The generator [gen] is used in case the [eval_point] equals [GX], in
               which case the resulting scalar is [x * gen]. *)
  val convert_eval_points :
    generator:Scalar.t -> x:Scalar.t -> eval_point list -> Scalar.t SMap.t

  (** [get_answer answers p name] extracts the evaluation of polynomial [name]
                at point [p] from the given [answers]. *)
  val get_answer : Scalar.t SMap.t SMap.t -> eval_point -> string -> Scalar.t

  (** A function to merge a list of prover identities into one. *)
  val merge_prover_identities : prover_identities list -> prover_identities

  (** A function to merge a list of verifier identities into one. *)
  val merge_verifier_identities :
    verifier_identities list -> verifier_identities
end = struct
  type prover_identities = Evaluations.t SMap.t -> Evaluations.t SMap.t

  type verifier_identities =
    Scalar.t -> Scalar.t SMap.t SMap.t -> Scalar.t SMap.t

  type eval_point = X | GX | Custom of string * Scalar.t [@@deriving repr]

  let string_of_eval_point = function
    | X -> "x"
    | GX -> "gx"
    | Custom (s, _) -> s

  let convert_eval_points ~generator ~x l =
    let eval = function
      | X -> x
      | GX -> Scalar.mul generator x
      | Custom (_, f) -> Scalar.mul f x
    in
    SMap.of_list @@ List.map (fun p -> (string_of_eval_point p, eval p)) l

  let get_answer answers x n =
    let x_map = SMap.find (string_of_eval_point x) answers in
    match SMap.find_opt n x_map with
    | Some x -> x
    | None ->
        raise
          (Invalid_argument
             (Printf.sprintf
                "Identities.get_answers : name '%s' not found in answers."
                n))

  let merge_prover_identities identities_list : prover_identities =
   fun evaluations ->
    List.fold_left
      (fun acc_map ids -> SMap.union_disjoint acc_map (ids evaluations))
      SMap.empty
      identities_list

  let merge_verifier_identities identities_list : verifier_identities =
   fun x answers ->
    List.fold_left
      (fun acc_map ids -> SMap.union_disjoint acc_map (ids x answers))
      SMap.empty
      identities_list
end

include Identities
OCaml

Innovation. Community. Security.

GitHub Discord Twitter Peertube RSS
About
Changelog Releases Industrial Users Academic Users Why OCaml
Ecosystem
Packages Community Events OCaml Planet Jobs
Resources
Install OCaml Get Started Platform Tools Language Manual Standard Library API Books Exercises Papers OCaml Playground Logo
Policies
Carbon Footprint Governance Privacy Code of Conduct