add to_octets

src/types.ml

@@ -82,6 +82,8 @@ module EddsaPublicKey = struct
      converted to Crockford Base32. *)
   type t = Mirage_crypto_ec.Ed25519.pub
 
+  let to_octets t = Mirage_crypto_ec.Ed25519.pub_to_octets t
+
   let of_b32 s =
     let open Syntax in
     let open Mirage_crypto_ec in
@@ -90,13 +92,14 @@ module EddsaPublicKey = struct
     | Error e -> Fmt.error "%a" pp_error e
     | Ok pub -> Ok pub
 
-  let to_b32 pub = pub |> Mirage_crypto_ec.Ed25519.pub_to_octets |> B32.encode
+  let to_b32 t = B32.encode (to_octets t)
   let jsont = Jsont.of_of_string ~kind:"EddsaPublicKey" of_b32 ~enc:to_b32
 end
 
 module EddsaSignature : sig
   type t
 
+  val to_octets : t -> string
   val sign : key:Mirage_crypto_ec.Ed25519.priv -> string -> t
   val of_b32 : string -> (t, string) result
   val to_b32 : t -> string
@@ -108,6 +111,8 @@ end = struct
      They are signature over a c-struct like `TALER_xxxPS` + with a purpose *)
   type t = string
 
+  let to_octets t = t
+
   (* TODO key format
      is it exactly like in GNU_CRYPTO?
      endianess issue? *)
@@ -128,6 +133,13 @@ end
 module RsaPublicKey = struct
   type t = Mirage_crypto_pk.Rsa.pub
 
+  let to_octets ({ n; e } : Mirage_crypto_pk.Rsa.pub) =
+    let open Binary_formats.RsaPublicKey in
+    let header = { n_len= Z.size n; e_len= Z.size e } in
+    let v = { header; n; e } in
+    let s = Bin.to_string bin v in
+    s
+
   let of_b32 s =
     let open Syntax in
     let* s = B32.decode s in
@@ -135,20 +147,14 @@ module RsaPublicKey = struct
     let+ v = Mirage_crypto_pk.Rsa.pub ~n:v.n ~e:v.e |> unwrap_err_msg in
     v
 
-  let to_b32 ({ n; e } : Mirage_crypto_pk.Rsa.pub) =
-    let open Binary_formats.RsaPublicKey in
-    let header = { n_len= Z.size n; e_len= Z.size e } in
-    let v = { header; n; e } in
-    let s = Bin.to_string bin v in
-    let s = B32.encode s in
-    s
-
+  let to_b32 t = B32.encode (to_octets t)
   let jsont = Jsont.of_of_string ~kind:"RsaPublicKey" of_b32 ~enc:to_b32
 end
 
 module RsaSignature : sig
   type t
 
+  val to_octets : t -> string
   val sign : key:Mirage_crypto_pk.Rsa.priv -> string -> t
   val of_b32 : string -> (t, string) result
   val to_b32 : t -> string
@@ -156,6 +162,8 @@ module RsaSignature : sig
 end = struct
   type t = string
 
+  let to_octets t = t
+
   (* no Rsa.sign(?):
      decrypt is equivalent to sign *)
   let sign ~key s =