ligo/src/lib_crypto/secp256k1.ml
2019-02-20 23:08:19 +01:00

294 lines
8.5 KiB
OCaml

(*****************************************************************************)
(* *)
(* Open Source License *)
(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
(* *)
(* Permission is hereby granted, free of charge, to any person obtaining a *)
(* copy of this software and associated documentation files (the "Software"),*)
(* to deal in the Software without restriction, including without limitation *)
(* the rights to use, copy, modify, merge, publish, distribute, sublicense, *)
(* and/or sell copies of the Software, and to permit persons to whom the *)
(* Software is furnished to do so, subject to the following conditions: *)
(* *)
(* The above copyright notice and this permission notice shall be included *)
(* in all copies or substantial portions of the Software. *)
(* *)
(* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*)
(* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *)
(* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL *)
(* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER*)
(* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING *)
(* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER *)
(* DEALINGS IN THE SOFTWARE. *)
(* *)
(*****************************************************************************)
module Public_key_hash = struct
include Blake2B.Make(Base58)(struct
let name = "Secp256k1.Public_key_hash"
let title = "A Secp256k1 public key hash"
let b58check_prefix = Base58.Prefix.secp256k1_public_key_hash
let size = Some 20
end)
module Logging = struct
let tag = Tag.def ~doc:title name pp
end
end
let () =
Base58.check_encoded_prefix Public_key_hash.b58check_encoding "tz2" 36
open Libsecp256k1.External
let context =
let ctx = Context.create () in
match Context.randomize ctx (Rand.generate 32) with
| false -> failwith "Secp256k1 context randomization failed. Aborting."
| true -> ctx
module Public_key = struct
type t = Key.public Key.t
let name = "Secp256k1.Public_key"
let title = "A Secp256k1 public key"
let to_bytes pk = Key.to_bytes context pk
let of_bytes_opt s =
try Some (Key.read_pk_exn context s)
with _ -> None
let to_string s = MBytes.to_string (to_bytes s)
let of_string_opt s = of_bytes_opt (MBytes.of_string s)
let size = Key.compressed_pk_bytes
type Base58.data +=
| Data of t
let b58check_encoding =
Base58.register_encoding
~prefix: Base58.Prefix.secp256k1_public_key
~length: size
~to_raw: to_string
~of_raw: of_string_opt
~wrap: (fun x -> Data x)
let () =
Base58.check_encoded_prefix b58check_encoding "sppk" 55
let hash v =
Public_key_hash.hash_bytes [to_bytes v]
include Compare.Make(struct
type nonrec t = t
let compare a b =
MBytes.compare (to_bytes a) (to_bytes b)
end)
include Helpers.MakeRaw(struct
type nonrec t = t
let name = name
let of_bytes_opt = of_bytes_opt
let of_string_opt = of_string_opt
let to_string = to_string
end)
include Helpers.MakeB58(struct
type nonrec t = t
let title = title
let name = name
let b58check_encoding = b58check_encoding
end)
include Helpers.MakeEncoder(struct
type nonrec t = t
let name = name
let title = title
let raw_encoding =
let open Data_encoding in
conv to_bytes of_bytes_exn (Fixed.bytes size)
let of_b58check = of_b58check
let of_b58check_opt = of_b58check_opt
let of_b58check_exn = of_b58check_exn
let to_b58check = to_b58check
let to_short_b58check = to_short_b58check
end)
let pp ppf t = Format.fprintf ppf "%s" (to_b58check t)
end
module Secret_key = struct
type t = Key.secret Key.t
let name = "Secp256k1.Secret_key"
let title = "A Secp256k1 secret key"
let size = Key.secret_bytes
let of_bytes_opt s =
match Key.read_sk context s with
| Ok x -> Some x
| _ -> None
let to_bytes x = Key.to_bytes context x
let to_string s = MBytes.to_string (to_bytes s)
let of_string_opt s = of_bytes_opt (MBytes.of_string s)
let to_public_key key = Key.neuterize_exn context key
type Base58.data +=
| Data of t
let b58check_encoding =
Base58.register_encoding
~prefix: Base58.Prefix.secp256k1_secret_key
~length: size
~to_raw: to_string
~of_raw: of_string_opt
~wrap: (fun x -> Data x)
let () =
Base58.check_encoded_prefix b58check_encoding "spsk" 54
include Compare.Make(struct
type nonrec t = t
let compare a b =
MBytes.compare (Key.buffer a) (Key.buffer b)
end)
include Helpers.MakeRaw(struct
type nonrec t = t
let name = name
let of_bytes_opt = of_bytes_opt
let of_string_opt = of_string_opt
let to_string = to_string
end)
include Helpers.MakeB58(struct
type nonrec t = t
let title = title
let name = name
let b58check_encoding = b58check_encoding
end)
include Helpers.MakeEncoder(struct
type nonrec t = t
let name = name
let title = title
let raw_encoding =
let open Data_encoding in
conv to_bytes of_bytes_exn (Fixed.bytes size)
let of_b58check = of_b58check
let of_b58check_opt = of_b58check_opt
let of_b58check_exn = of_b58check_exn
let to_b58check = to_b58check
let to_short_b58check = to_short_b58check
end)
let pp ppf t = Format.fprintf ppf "%s" (to_b58check t)
end
type t = Sign.plain Sign.t
type watermark = MBytes.t
let name = "Secp256k1"
let title = "A Secp256k1 signature"
let size = Sign.plain_bytes
let of_bytes_opt s =
match Sign.read context s with Ok s -> Some s | Error _ -> None
let to_bytes = Sign.to_bytes ~der:false context
let to_string s = MBytes.to_string (to_bytes s)
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: Base58.Prefix.secp256k1_signature
~length: size
~to_raw: to_string
~of_raw: of_string_opt
~wrap: (fun x -> Data x)
let () =
Base58.check_encoded_prefix b58check_encoding "spsig1" 99
include Compare.Make(struct
type nonrec t = t
let compare a b =
MBytes.compare (Sign.buffer a) (Sign.buffer b)
end)
include Helpers.MakeRaw(struct
type nonrec t = t
let name = name
let of_bytes_opt = of_bytes_opt
let of_string_opt = of_string_opt
let to_string = to_string
end)
include Helpers.MakeB58(struct
type nonrec t = t
let title = title
let name = name
let b58check_encoding = b58check_encoding
end)
include Helpers.MakeEncoder(struct
type nonrec t = t
let name = name
let title = title
let raw_encoding =
let open Data_encoding in
conv to_bytes of_bytes_exn (Fixed.bytes size)
let of_b58check = of_b58check
let of_b58check_opt = of_b58check_opt
let of_b58check_exn = of_b58check_exn
let to_b58check = to_b58check
let to_short_b58check = to_short_b58check
end)
let pp ppf t = Format.fprintf ppf "%s" (to_b58check t)
let zero = of_bytes_exn (MBytes.make size '\000')
let sign ?watermark sk msg =
let msg =
Blake2B.to_bytes @@
Blake2B.hash_bytes @@
match watermark with
| None -> [msg]
| Some prefix -> [ prefix ; msg ] in
Sign.sign_exn context ~sk msg
let check ?watermark public_key signature msg =
let msg =
Blake2B.to_bytes @@
Blake2B.hash_bytes @@
match watermark with
| None -> [msg]
| Some prefix -> [ prefix ; msg ] in
Sign.verify_exn context ~pk:public_key ~msg ~signature
let generate_key ?(seed=Rand.generate 32) () =
let sk = Key.read_sk_exn context seed in
let pk = Key.neuterize_exn context sk in
let pkh = Public_key.hash pk in
pkh, pk, sk
let deterministic_nonce sk msg =
Hacl.Hash.SHA256.HMAC.digest ~key: (Secret_key.to_bytes sk) ~msg
let deterministic_nonce_hash sk msg =
Blake2B.to_bytes (Blake2B.hash_bytes [deterministic_nonce sk msg])