Signer/Encrypted: use custom Base58Check prefixes

src/lib_crypto/base58.ml

@@ -320,6 +320,11 @@ module Prefix = struct
   let secp256k1_secret_key = "\017\162\224\201" (* spsk(54) *)
   let p256_secret_key = "\016\081\238\189" (* p2sk(54) *)
 
+  (* 56 *)
+  let ed25519_encrypted_seed = "\007\090\060\179\041" (* edesk(88) *)
+  let secp256k1_encrypted_secret_key = "\009\237\241\174\150" (* spesk(88) *)
+  let p256_encrypted_secret_key = "\009\048\057\115\171" (* p2esk(88) *)
+
   (* 33 *)
   let secp256k1_public_key = "\003\254\226\086" (* sppk(55) *)
   let p256_public_key = "\003\178\139\127" (* p2pk(55) *)

src/lib_crypto/base58.mli

@@ -31,6 +31,10 @@ module Prefix : sig
   val p256_public_key: string
   val p256_secret_key: string
   val p256_signature: string
+  val ed25519_encrypted_seed: string
+  val secp256k1_encrypted_secret_key: string
+  val p256_encrypted_secret_key: string
+
   val generic_signature: string
   val chain_id: string
 

src/lib_signer_backends/encrypted.ml

@@ -7,6 +7,10 @@
 (*                                                                        *)
 (**************************************************************************)
 
+type Base58.data += Encrypted_ed25519 of MBytes.t
+type Base58.data += Encrypted_secp256k1 of MBytes.t
+type Base58.data += Encrypted_p256 of MBytes.t
+
 open Client_keys
 
 let scheme = "encrypted"
@@ -19,31 +23,99 @@ module Raw = struct
   (* Fixed zero nonce *)
   let nonce = Crypto_box.zero_nonce
 
+  (* Secret keys for Ed25519, secp256k1, P256 are 32 bytes long. *)
+  let encrypted_size = Crypto_box.boxzerobytes + 32
+
   let pbkdf ~salt ~password =
     Cstruct.to_bigarray
-      (Pbkdf.pbkdf2 ~prf:`SHA512 ~count:2048 ~dk_len:32l
+      (Pbkdf.pbkdf2 ~prf:`SHA512 ~count:32768 ~dk_len:32l
          ~salt: (Cstruct.of_bigarray salt)
          ~password: (Cstruct.of_bigarray password))
 
   let encrypt ~password sk =
     let salt = Rand.generate salt_len in
-    let key = Crypto_box.Secretbox.unsafe_of_bytes (pbkdf ~password ~salt) in
-    let msg = Data_encoding.Binary.to_bytes_exn Signature.Secret_key.encoding sk in
-    let encrypted_passwd = Crypto_box.Secretbox.box key msg nonce in
-    MBytes.concat "" [ salt ; encrypted_passwd ]
-
-  let decrypt ~password ~encrypted_sk =
-    let len = MBytes.length encrypted_sk in
-    let salt = MBytes.sub encrypted_sk 0 salt_len in
-    let encrypted_sk = MBytes.sub encrypted_sk salt_len (len - salt_len) in
     let key = Crypto_box.Secretbox.unsafe_of_bytes (pbkdf ~salt ~password) in
-    match Crypto_box.Secretbox.box_open key encrypted_sk nonce with
+    let msg =
-    | None -> return_none
+      match (sk : Signature.secret_key) with
-    | Some bytes ->
+      | Ed25519 sk ->
-        match Data_encoding.Binary.of_bytes Signature.Secret_key.encoding bytes with
+          Data_encoding.Binary.to_bytes_exn Ed25519.Secret_key.encoding sk
-        | None -> failwith "Corrupted wallet, deciphered key is invalid"
+      | Secp256k1 sk ->
-        | Some sk -> return_some sk
+          Data_encoding.Binary.to_bytes_exn Secp256k1.Secret_key.encoding sk
+      | P256 sk ->
+          Data_encoding.Binary.to_bytes_exn P256.Secret_key.encoding sk in
+    MBytes.concat "" [ salt ;
+                       Crypto_box.Secretbox.box key msg nonce ]
 
+  let decrypt algo ~password ~encrypted_sk =
+    let salt = MBytes.sub encrypted_sk 0 salt_len in
+    let encrypted_sk =
+      MBytes.sub encrypted_sk salt_len encrypted_size in
+    let key = Crypto_box.Secretbox.unsafe_of_bytes (pbkdf ~salt ~password) in
+    match Crypto_box.Secretbox.box_open key encrypted_sk nonce, algo with
+    | None, _ -> return_none
+    | Some bytes, Signature.Ed25519 -> begin
+        match Data_encoding.Binary.of_bytes Ed25519.Secret_key.encoding bytes with
+        | Some sk -> return_some (Ed25519 sk : Signature.Secret_key.t)
+        | None -> failwith "Corrupted wallet, deciphered key is not a \
+                            valid Ed25519 secret key"
+      end
+    | Some bytes, Signature.Secp256k1 -> begin
+        match Data_encoding.Binary.of_bytes Secp256k1.Secret_key.encoding bytes with
+        | Some sk -> return_some (Secp256k1 sk : Signature.Secret_key.t)
+        | None -> failwith "Corrupted wallet, deciphered key is not a \
+                            valid Secp256k1 secret key"
+      end
+    | Some bytes, Signature.P256 -> begin
+        match Data_encoding.Binary.of_bytes P256.Secret_key.encoding bytes with
+        | Some sk -> return_some (P256 sk : Signature.Secret_key.t)
+        | None -> failwith "Corrupted wallet, deciphered key is not a \
+                            valid P256 secret key"
+      end
+end
+
+module Encodings = struct
+
+  let ed25519 =
+    let length =
+      Hacl.Sign.skbytes + Crypto_box.boxzerobytes + Raw.salt_len in
+    Base58.register_encoding
+      ~prefix: Base58.Prefix.ed25519_encrypted_seed
+      ~length
+      ~to_raw: (fun sk -> MBytes.to_string sk)
+      ~of_raw: (fun buf ->
+          if String.length buf <> length then None
+          else Some (MBytes.of_string buf))
+      ~wrap: (fun sk -> Encrypted_ed25519 sk)
+
+  let secp256k1 =
+    let open Libsecp256k1.External in
+    let length =
+      Key.secret_bytes + Crypto_box.boxzerobytes +Raw.salt_len in
+    Base58.register_encoding
+      ~prefix: Base58.Prefix.secp256k1_encrypted_secret_key
+      ~length
+      ~to_raw: (fun sk -> MBytes.to_string sk)
+      ~of_raw: (fun buf ->
+          if String.length buf <> length then None
+          else Some (MBytes.of_string buf))
+      ~wrap: (fun sk -> Encrypted_secp256k1 sk)
+
+  let p256 =
+    let length =
+      Uecc.(sk_size secp256r1) + Crypto_box.boxzerobytes + Raw.salt_len in
+    Base58.register_encoding
+      ~prefix: Base58.Prefix.p256_encrypted_secret_key
+      ~length
+      ~to_raw: (fun sk -> MBytes.to_string sk)
+      ~of_raw: (fun buf ->
+          if String.length buf <> length then None
+          else Some (MBytes.of_string buf))
+      ~wrap: (fun sk -> Encrypted_p256 sk)
+
+  let () =
+    Base58.check_encoded_prefix ed25519 "edesk" 88 ;
+    Base58.check_encoded_prefix secp256k1 "spesk" 88 ;
+    Base58.check_encoded_prefix p256 "p2esk" 88
 end
 
 let decrypted = Hashtbl.create 13
@@ -51,9 +123,8 @@ let passwords = ref []
 
 let rec interactive_decrypt_loop
     (cctxt : #Client_context.prompter)
-    ?name ~encrypted_sk =
+    ?name ~encrypted_sk algo =
-  begin
+  begin match name with
-    match name with
     | None ->
         cctxt#prompt_password
           "Enter password for encrypted key: "
@@ -61,30 +132,35 @@ let rec interactive_decrypt_loop
         cctxt#prompt_password
           "Enter password for encrypted key \"%s\": " name
   end >>=? fun password ->
-  Raw.decrypt ~password ~encrypted_sk >>=? function
+  Raw.decrypt algo ~password ~encrypted_sk >>=? function
-  | None ->
-      interactive_decrypt_loop cctxt ?name ~encrypted_sk
   | Some sk ->
       passwords := password :: !passwords ;
       return sk
+  | None ->
+      interactive_decrypt_loop cctxt ?name ~encrypted_sk algo
 
-let rec noninteractice_decrypt_loop ~encrypted_sk = function
+let rec noninteractice_decrypt_loop algo ~encrypted_sk = function
   | [] -> return_none
   | password :: passwords ->
-      Raw.decrypt ~password ~encrypted_sk >>=? function
+      Raw.decrypt algo ~password ~encrypted_sk >>=? function
-      | None -> noninteractice_decrypt_loop ~encrypted_sk passwords
+      | None -> noninteractice_decrypt_loop algo ~encrypted_sk passwords
       | Some sk -> return_some sk
 
 let decrypt_payload cctxt ?name encrypted_sk =
-  match Base58.safe_decode encrypted_sk with
+  begin match Base58.decode encrypted_sk with
-  | None -> failwith "Not a Base58 encoded encrypted key"
+    | Some (Encrypted_ed25519 encrypted_sk) ->
-  | Some encrypted_sk ->
+        return (Signature.Ed25519, encrypted_sk)
-      let encrypted_sk = MBytes.of_string encrypted_sk in
+    | Some (Encrypted_secp256k1 encrypted_sk) ->
-      noninteractice_decrypt_loop ~encrypted_sk !passwords >>=? function
+        return (Signature.Secp256k1, encrypted_sk)
+    | Some (Encrypted_p256 encrypted_sk) ->
+        return (Signature.P256, encrypted_sk)
+    | _ -> failwith "Not a Base58Check-encoded encrypted key"
+  end >>=? fun (algo, encrypted_sk) ->
+  noninteractice_decrypt_loop algo ~encrypted_sk !passwords >>=? function
   | Some sk -> return sk
-      | None -> interactive_decrypt_loop cctxt ?name ~encrypted_sk
+  | None -> interactive_decrypt_loop cctxt ?name ~encrypted_sk algo
 
-let decrypt cctxt ?name sk_uri =
+let decrypt (cctxt : #Client_context.prompter) ?name sk_uri =
   let payload = Uri.path (sk_uri : sk_uri :> Uri.t) in
   decrypt_payload cctxt ?name payload >>=? fun sk ->
   Hashtbl.replace decrypted sk_uri sk ;
@@ -114,7 +190,11 @@ let rec read_passphrase (cctxt : #Client_context.io) =
 let encrypt cctxt sk =
   read_passphrase cctxt >>=? fun password ->
   let payload = Raw.encrypt ~password sk in
-  let path = Base58.safe_encode (MBytes.to_string payload) in
+  let encoding = match sk with
+    | Ed25519 _ -> Encodings.ed25519
+    | Secp256k1 _ -> Encodings.secp256k1
+    | P256 _ -> Encodings.p256 in
+  let path = Base58.simple_encode encoding payload in
   let sk_uri = Client_keys.make_sk_uri (Uri.make ~scheme ~path ()) in
   Hashtbl.replace decrypted sk_uri sk ;
   return sk_uri

src/lib_signer_backends/encrypted.mli

@@ -10,7 +10,7 @@
 module Make(C : sig val cctxt: Client_context.prompter end) : Client_keys.SIGNER
 
 val decrypt:
-  #Client_context.io_wallet ->
+  #Client_context.prompter ->
   ?name:string ->
   Client_keys.sk_uri -> Signature.secret_key tzresult Lwt.t