ok denom group + exchange_sig

src/denomination.ml

@@ -16,7 +16,7 @@ type t = {
   master_sig: Signatures.DenominationKeyValidity.t;
 }
 
-let make_denom_group denominations =
+let make_denom_group_sorted denominations =
   let open Syntax in
   let ht = Hashtbl.create 0xff in
   List.iter
@@ -72,19 +72,41 @@ let make_denom_group denominations =
         Hashtbl.replace ht k (v :: l))
       denominations
   in
-  Hashtbl.to_seq ht
-  |> List.of_seq
-  |> List.map
-       (fun
-         ((value, fee_withdraw, fee_deposit, fee_refresh, fee_refund), denoms)
-       ->
-         Api.DenomGroup.Rsa
-           Api.RsaDenomGroup.
+
+  (* ! important for /keys .exchange_sig
+     each group must be ordered in _reverse_ chronological order
+     order of groups to compute hash, must be the same as the order
+     in /keys .denominations *)
+  let open Api in
+  let open DenomGroup in
+  let open RsaDenomGroup in
+  let open RsaDenom in
+  let cmp_denom b a = Timestamp.compare a.stamp_start b.stamp_start in
+  let cmp_group =
+    let cmp_amount a b =
+      let open Amount in
+      match Int64.unsigned_compare a.value b.value with
+      | 0 -> Int32.unsigned_compare a.fraction b.fraction
+      | n -> n
+    in
+    fun (Rsa a) (Rsa b) -> cmp_amount a.value b.value
+  in
+  let l =
+    Hashtbl.to_seq ht
+    |> List.of_seq
+    |> List.map
+         (fun
+           ((value, fee_withdraw, fee_deposit, fee_refresh, fee_refund), denoms)
+         ->
+           Rsa
              {
-               denoms;
+               denoms= List.sort cmp_denom denoms;
                value;
                fee_withdraw;
                fee_deposit;
                fee_refresh;
                fee_refund;
              })
+    |> List.sort cmp_group
+  in
+  l