From 56694e9b3ed43de1af48fecbb10a535814aa90f7 Mon Sep 17 00:00:00 2001
From: swrup <swrup@protonmail.com>
Date: Sat, 18 Oct 2025 14:55:16 +0200
Subject: [PATCH]

---
 src/binary_formats.ml | 99 +++++++++++++++++++++++++++----------------
 1 file changed, 63 insertions(+), 36 deletions(-)

diff --git a/src/binary_formats.ml b/src/binary_formats.ml
index c0bbb70e..83cb48c9 100644
--- a/src/binary_formats.ml
+++ b/src/binary_formats.ml
@@ -41,29 +41,38 @@
 let int32_size = 4
 let int64_size = 8
 
+(* -- Time -- *)
+
+(* microseconds since the UNIX Epoch
+   UINT64_MAX represents "never" *)
+module MK_TIME () = struct
+  type t = { v: int64 }
+
+  (* not BE (?) *)
+  let bin =
+    let open Bin in
+    record (fun v -> { v }) |+ field neint64 (fun t -> t.v) |> sealr
+end
+
+module MK_TIME_NBO () = struct
+  type t = { v: int64 }
+
+  let bin =
+    let open Bin in
+    record (fun v -> { v }) |+ field beint64 (fun t -> t.v) |> sealr
+end
+
+module TimeAbsolute = MK_TIME ()
+module TimeAbsoluteNBO = MK_TIME_NBO ()
+module TimeRelative = MK_TIME ()
+module TimeRelativeNBO = MK_TIME_NBO ()
+module Timestamp = MK_TIME ()
+module TimestampNBO = MK_TIME_NBO ()
+
 (* TODO clean up
    ? rm all of UTIL
    ? Bin.map int64 to Ptime.t here *)
 module UTIL = struct
-  (* microseconds since the UNIX Epoch
-   UINT64_MAX represents "never" *)
-  module MK_TIME () = struct
-    type t = { v: int64 }
-
-    (* not BE (?) *)
-    let bin =
-      let open Bin in
-      record (fun v -> { v }) |+ field neint64 (fun t -> t.v) |> sealr
-  end
-
-  module MK_TIME_NBO () = struct
-    type t = { v: int64 }
-
-    let bin =
-      let open Bin in
-      record (fun v -> { v }) |+ field beint64 (fun t -> t.v) |> sealr
-  end
-
   module type Bytes_sig = sig
     type t = { v: string }
 
@@ -196,20 +205,41 @@ module UTIL = struct
   module MK_HASH_32 () : H_sig = struct
     include HHH_32
   end
+
+  module MK_SRC_HASH_64 (M : sig
+    type src
+
+    val to_octets : src -> string
+  end) : sig
+    type t
+
+    val bin : t Bin.t
+    val hash : M.src -> t
+  end = struct
+    include Hash_64
+
+    let hash src = hash (M.to_octets src)
+  end
+
+  module MK_SRC_HASH_32 (M : sig
+    type src
+
+    val to_octets : src -> string
+  end) : sig
+    type t
+
+    val bin : t Bin.t
+    val hash : M.src -> t
+  end = struct
+    include Hash_32
+
+    let hash src = hash (M.to_octets src)
+  end
 end
 
 include UTIL
 module Taler_signatures = Include.Taler_signatures
 
-(* -- Time -- *)
-
-module TimeAbsolute = MK_TIME ()
-module TimeAbsoluteNBO = MK_TIME_NBO ()
-module TimeRelative = MK_TIME ()
-module TimeRelativeNBO = MK_TIME_NBO ()
-module Timestamp = MK_TIME ()
-module TimestampNBO = MK_TIME_NBO ()
-
 (* -- Cryptographic primitives -- *)
 
 (* GNUNET_CRYPTO format *)
@@ -274,15 +304,12 @@ module GNUNET_RsaPublicKey = struct
     t
 end
 
-module DenominationHash = struct
-  include Hash_64
+module DenominationHash = MK_SRC_HASH_32 (struct
+  type src = Mirage_crypto_pk.Rsa.pub
 
-  let hash (pub : Mirage_crypto_pk.Rsa.pub) =
-    pub
-    |> GNUNET_RsaPublicKey.of_pub
-    |> Bin.to_string GNUNET_RsaPublicKey.bin
-    |> hash
-end
+  let to_octets pub =
+    GNUNET_RsaPublicKey.of_pub pub |> Bin.to_string GNUNET_RsaPublicKey.bin
+end)
 
 module ExchangePublicKeyP = struct
   type t = Mirage_crypto_ec.Ed25519.pub