Base58: regroup prefix definition.

src/lib_crypto/base58.ml

@@ -327,6 +327,7 @@ module Prefix = struct
   let ed25519_secret_key = "\043\246\078\007" (* edsk(98) *)
   let ed25519_signature = "\009\245\205\134\018" (* edsig(99) *)
   let secp256k1_signature =  "\013\115\101\019\063" (* spsig1(99) *)
+  let generic_signature = "\004\130\043" (* sig(96) *)
 
   (* 4 *)
   let chain_id = "\087\082\000" (* Net(15) *)

src/lib_crypto/base58.mli

@@ -27,6 +27,7 @@ module Prefix : sig
   val secp256k1_public_key: string
   val secp256k1_secret_key: string
   val secp256k1_signature: string
+  val generic_signature: string
   val chain_id: string
 
 end

src/lib_crypto/signature.ml

@@ -348,12 +348,15 @@ let of_string_opt s = of_bytes_opt (MBytes.of_string s)
 type Base58.data += Data of t
 let b58check_encoding =
   Base58.register_encoding
-    ~prefix: "\004\130\043"
-    ~length: 96
+    ~prefix: Base58.Prefix.generic_signature
+    ~length: Ed25519.size
     ~to_raw: to_string
     ~of_raw: of_string_opt
     ~wrap: (fun x -> Data x)
 
+let () =
+  Base58.check_encoded_prefix b58check_encoding "sig" 96
+
 include Helpers.MakeRaw(struct
     type nonrec t = t
     let name = name