From c946cb0358976b163ff18e683997662bc2ae2e96 Mon Sep 17 00:00:00 2001
From: swrup <swrup@protonmail.com>
Date: Fri, 17 Oct 2025 15:25:10 +0200
Subject: [PATCH] + DenominationKeyAnnouncementPS.bin

---
 src/binary_formats.ml | 17 ++++++++++++++---
 src/management.ml     |  5 ++---
 src/syntax.ml         |  3 +++
 src/types.ml          | 15 +++++----------
 src/util.ml           |  8 ++++++++
 5 files changed, 32 insertions(+), 16 deletions(-)

diff --git a/src/binary_formats.ml b/src/binary_formats.ml
index 0a6816aa..4037a7eb 100644
--- a/src/binary_formats.ml
+++ b/src/binary_formats.ml
@@ -442,6 +442,8 @@ module WithdrawConfirmationPS = struct
 end
 
 module DenominationKeyAnnouncementPS = struct
+  (* TODO taler_signatures purpose
+     we use TALER_SIGNATURE_SM_RSA_DENOMINATION_KEY instead here *)
   (* purpose.purpose = TALER_SIGNATURE_SM_DENOMINATION_KEY *)
   type t = {
     h_denom_pub: DenominationHash.t;
@@ -450,9 +452,18 @@ module DenominationKeyAnnouncementPS = struct
     duration_withdraw: TimeRelativeNBO.t;
   }
 
-  (* TODO management *)
-  (* let bin = ... *)
-  let to_string _ = assert false
+  let bin =
+    let open Bin in
+    Purpose.make_bin Taler_signatures.sm_rsa_denomination_key @@ fun purpose ->
+    record
+      (fun _purpose h_denom_pub h_section_name anchor_time duration_withdraw ->
+        { h_denom_pub; h_section_name; anchor_time; duration_withdraw })
+    |+ Purpose.field purpose
+    |+ field DenominationHash.bin (fun t -> t.h_denom_pub)
+    |+ field HashCode.bin (fun t -> t.h_section_name)
+    |+ field TimeAbsoluteNBO.bin (fun t -> t.anchor_time)
+    |+ field TimeRelativeNBO.bin (fun t -> t.duration_withdraw)
+    |> sealr
 end
 
 module SingleWithdrawRequestPS = struct
diff --git a/src/management.ml b/src/management.ml
index 78a00237..cbc4a510 100644
--- a/src/management.ml
+++ b/src/management.ml
@@ -48,13 +48,12 @@ let mk_future_denom denom_secmod_sign_f
     ps
     |>
     (* TODO implement
-       DenominationKeyAnnouncementPS.bin
        SigningKeyAnnouncementPS.bin *)
-    Binary_formats.DenominationKeyAnnouncementPS.to_string
+    Bin.to_string Binary_formats.DenominationKeyAnnouncementPS.bin
     |>
     (* TODO sig type *)
     (* Signature by the denomination security module
-       not this denomination rsa signature *)
+       (not this denomination rsa signature) *)
     denom_secmod_sign_f
   in
   FutureDenom.
diff --git a/src/syntax.ml b/src/syntax.ml
index 53b7cb66..da6c9b01 100644
--- a/src/syntax.ml
+++ b/src/syntax.ml
@@ -1,6 +1,9 @@
 let ( let* ) o f = match o with Ok v -> f v | Error _ as e -> e
 let ( let+ ) o f = match o with Ok v -> Ok (f v) | Error _ as e -> e
 
+(* TODO use polymorphic variant for errors *)
+let unwrap_err_msg o = match o with Error (`Msg e) -> Error e | Ok v -> Ok v
+
 let list_iter f l =
   let err = ref None in
   try
diff --git a/src/types.ml b/src/types.ml
index cd87f1e5..e80498e6 100644
--- a/src/types.ml
+++ b/src/types.ml
@@ -108,16 +108,11 @@ module RsaPublicKey = struct
   type t = Mirage_crypto_pk.Rsa.pub
 
   let of_string s =
-    (* TODO bin
-       - no [Bin.of_string] ?
-       - what to do with the int ref? *)
-    match B32.decode s with
-    | Error _ as err -> err
-    | Ok s -> (
-        let off = ref 0 in
-        let v = Bin.decode Binary_formats.RsaPublicKey.bin s off in
-        let res = Mirage_crypto_pk.Rsa.pub ~n:v.n ~e:v.e in
-        match res with Error (`Msg e) -> Error e | Ok pub -> Ok pub)
+    let open Syntax in
+    let* s = B32.decode s in
+    let* v = Util.bin_of_string Binary_formats.RsaPublicKey.bin s in
+    let+ v = Mirage_crypto_pk.Rsa.pub ~n:v.n ~e:v.e |> unwrap_err_msg in
+    v
 
   let to_string ({ n; e } : Mirage_crypto_pk.Rsa.pub) =
     let open Binary_formats.RsaPublicKey in
diff --git a/src/util.ml b/src/util.ml
index 7e205a51..36619bb6 100644
--- a/src/util.ml
+++ b/src/util.ml
@@ -20,3 +20,11 @@ let ptime_add_span_exn p span =
   match Ptime.add_span p span with
   | None -> Fmt.failwith "Ptime.add_span: not in the range [min;max]"
   | Some v -> v
+
+(* -- *** -- *)
+
+(* TODO bin
+   - no [Bin.of_string] ? *)
+let bin_of_string bin s =
+  let v = Bin.decode bin s (ref 0) in
+  Ok v