In tool modules, all Run functors take an abstract GROUP

src/bin/credgen.ml

@@ -44,7 +44,7 @@ module type PARAMS = sig
   val file : string option
   val derive : string option
   val dir : string
-  module G : Group_field.GROUP
+  module G : GROUP
 end
 
 let parse_args () = begin
@@ -129,7 +129,7 @@ module Run (P : PARAMS) : EMPTY = struct
     let hex = do_derive uuid x in
     let x = Z.(of_string_base 16 hex mod G.q) in
     let y = G.(g **~ x) in
-    Z.to_string y
+    G.to_string y
 
   let count, ids =
     match count, file, derive with

src/bin/election_tool.ml

@@ -51,8 +51,8 @@ module type PARAMS = sig
   val params : ff_pubkey params
   val election_fingerprint : string
   val group :  ff_params
-  val y : number
-  module G : Group_field.GROUP
+  module G : GROUP
+  val y : G.t
 end
 
 
@@ -150,21 +150,24 @@ module Run (P : PARAMS) : EMPTY = struct
   module M = Election.MakeSimpleMonad(G)
   module E = Election.MakeElection(G)(M);;
 
+  let read_elt = make_read G.of_string
+  let write_elt = make_write G.to_string
+
   (* Load and check trustee keys, if present *)
 
   module KG = Election.MakeSimpleDistKeyGen(G)(M);;
 
   let public_keys_with_pok =
     load_from_file (
-      trustee_public_key_of_string read_number
+      trustee_public_key_of_string read_elt
     ) "public_keys.jsons" |> option_map Array.of_list
 
   let () =
     match public_keys_with_pok with
     | Some pks ->
       assert (Array.forall KG.check pks);
       let y' = KG.combine pks in
-      assert (P.y =% y')
+      assert G.(y =~ y')
     | None -> ()
 
   let public_keys =
@@ -186,27 +189,27 @@ module Run (P : PARAMS) : EMPTY = struct
 
   (* Load ballots, if present *)
 
-  module ZSet = Set.Make(Z)
+  module GSet = Set.Make (G)
 
   let public_creds =
-    load_from_file Z.of_string "public_creds.txt" |>
+    load_from_file G.of_string "public_creds.txt" |>
     option_map (fun xs ->
       List.fold_left (fun accu x ->
-        ZSet.add x accu
-      ) ZSet.empty xs
+        GSet.add x accu
+      ) GSet.empty xs
     )
 
   let ballots =
     load_from_file (fun line ->
-      ballot_of_string read_number line,
+      ballot_of_string read_elt line,
       sha256_b64 line
     ) "ballots.jsons"
 
   let check_signature_present =
     match public_creds with
     | Some creds -> (fun b ->
       match b.signature with
-      | Some s -> ZSet.mem s.s_public_key creds
+      | Some s -> GSet.mem s.s_public_key creds
       | None -> false
     )
     | None -> (fun _ -> true)
@@ -245,7 +248,7 @@ module Run (P : PARAMS) : EMPTY = struct
         in
         let b = E.create_ballot e ?sk (E.make_randomness e ()) b () in
         assert (E.check_ballot e b);
-        print_endline (string_of_ballot write_number b)
+        print_endline (string_of_ballot write_elt b)
       | _ -> failwith "invalid plaintext ballot file"
       )
 
@@ -255,15 +258,15 @@ module Run (P : PARAMS) : EMPTY = struct
       (match load_from_file (number_of_string) fn with
         | Some [sk] ->
           let pk = G.(g **~ sk) in
-          if Array.forall (fun x -> not (x =% pk)) pks then (
+          if Array.forall (fun x -> not G.(x =~ pk)) pks then (
             Printf.eprintf "Warning: your key is not present in public_keys.jsons!\n";
           );
           let tally = Lazy.force encrypted_tally in
           let factor =
             E.compute_factor tally sk ()
           in
           assert (E.check_factor tally pk factor);
-          print_endline (string_of_partial_decryption write_number factor)
+          print_endline (string_of_partial_decryption write_elt factor)
         | _ -> failwith "invalid private key file"
       )
     | None -> ()
@@ -272,7 +275,7 @@ module Run (P : PARAMS) : EMPTY = struct
 
   let result =
     load_from_file (
-      result_of_string read_number
+      result_of_string read_elt
     ) "result.json"
 
   let () =
@@ -283,7 +286,7 @@ module Run (P : PARAMS) : EMPTY = struct
       failwith "invalid result file"
     | None ->
       let factors = load_from_file (
-        partial_decryption_of_string read_number
+        partial_decryption_of_string read_elt
       ) "partial_decryptions.jsons" |> option_map Array.of_list in
       match factors with
       | Some factors ->
@@ -293,7 +296,7 @@ module Run (P : PARAMS) : EMPTY = struct
         assert (E.check_result e result);
         if do_finalize then (
           save_to "result.json" (
-            write_result write_number
+            write_result write_elt
           ) result;
           Printf.eprintf "result.json written\n%!"
         );

src/bin/mkelection.ml

@@ -26,8 +26,9 @@ open Common
 
 module type PARAMS = sig
   val uuid : Uuidm.t
-  val template : template
-  module G : Group_field.GROUP
+  module G : GROUP
+  val params : G.t -> G.t wrapped_pubkey params
+  val write_params : Bi_outbuf.t -> G.t wrapped_pubkey params -> unit
 end
 
 let parse_args () = begin
@@ -70,6 +71,8 @@ let parse_args () = begin
       r
   in
 
+  let {g; p; q} = group in
+
   let module P = struct
 
     let uuid = match !uuid with
@@ -90,6 +93,17 @@ let parse_args () = begin
 
     module G = (val Group_field.make group : Group_field.GROUP)
 
+    let params y = {
+      e_description = template.t_description;
+      e_name = template.t_name;
+      e_public_key = {ffpk_g = g; ffpk_p = p; ffpk_q = q; ffpk_y = y};
+      e_questions = template.t_questions;
+      e_uuid = uuid;
+      e_short_name = template.t_short_name;
+    }
+
+    let write_params = write_params write_ff_pubkey
+
   end in
 
   (module P : PARAMS)
@@ -99,6 +113,8 @@ end
 module Run (P : PARAMS) : EMPTY = struct
   open P
 
+  let read_elt = make_read G.of_string
+
   (* Setup group *)
 
   module M = Election.MakeSimpleMonad(G);;
@@ -118,7 +134,7 @@ module Run (P : PARAMS) : EMPTY = struct
     in
     close_in ic;
     let keys = List.map (fun x ->
-      trustee_public_key_of_string read_number x
+      trustee_public_key_of_string read_elt x
     ) raw_keys |> Array.of_list in
     assert (Array.forall KG.check keys);
     keys
@@ -127,20 +143,11 @@ module Run (P : PARAMS) : EMPTY = struct
 
   (* Setup election *)
 
-  let {g; p; q} = G.group
-
-  let params = {
-    e_description = P.template.t_description;
-    e_name = P.template.t_name;
-    e_public_key = {ffpk_g = g; ffpk_p = p; ffpk_q = q; ffpk_y = y};
-    e_questions = P.template.t_questions;
-    e_uuid = P.uuid;
-    e_short_name = P.template.t_short_name;
-  }
+  let params = P.params y
 
   (* Save to disk *)
 
-  let () = save_to "election.json" (write_params write_ff_pubkey) params
+  let () = save_to "election.json" write_params params
 
 end
 

src/bin/tkeygen.ml

@@ -25,7 +25,7 @@ open Signatures
 open Common
 
 module type PARAMS = sig
-  module G : Group_field.GROUP
+  module G : GROUP
 end
 
 let parse_args () = begin
@@ -76,6 +76,8 @@ end
 module Run (P : PARAMS) : EMPTY = struct
   open P
 
+  let write_elt = make_write G.to_string
+
   (* Setup group *)
 
   module M = Election.MakeSimpleMonad(G);;
@@ -89,7 +91,7 @@ module Run (P : PARAMS) : EMPTY = struct
   (* Save to file *)
 
   let id = String.sub
-    (sha256_hex (Z.to_string public_key.trustee_public_key))
+    (sha256_hex (G.to_string public_key.trustee_public_key))
     0 8 |> String.uppercase
   ;;
 
@@ -100,7 +102,7 @@ module Run (P : PARAMS) : EMPTY = struct
     id ^ ".pubkey",
     0o444,
     public_key,
-    write_trustee_public_key write_number
+    write_trustee_public_key write_elt
 
   let privkey =
     "private",