From 08512e74fa39dba2c8a09922f46f9d828fb5e81a Mon Sep 17 00:00:00 2001 From: swrup Date: Fri, 17 Oct 2025 22:04:35 +0200 Subject: [PATCH] wip: implement hash need good handling of 0-terminated C-string --- src/binary_formats.ml | 198 +++++++++++++++++++++++++++++------------- src/dune | 1 + src/management.ml | 12 +-- src/types.ml | 4 +- test/test.ml | 4 + 5 files changed, 148 insertions(+), 71 deletions(-) diff --git a/src/binary_formats.ml b/src/binary_formats.ml index 9a17ee57..60eb5535 100644 --- a/src/binary_formats.ml +++ b/src/binary_formats.ml @@ -24,7 +24,18 @@ - exchange and gana master branch are not in sync and we should use a specific git tag instead - outdated doc(?) - - some missing struct documentation *) + - some missing struct documentation + + - correctly handle endianness *) + +(* TODO hash and C(ancer)-terminated strings + + - "A JSON object is canonicalized by converting it to an ASCII byte array + with the algorithm specified in RFC 8785. The resulting bytes are + terminated with a single 0-byte and then hashed with SHA512." + - from the code it looks like its the same for all stringy-strings + !! not strings that are raw-bytes-data-like + *) module UTIL = struct let int32_size = 4 @@ -71,9 +82,21 @@ module UTIL = struct record (fun v -> { v }) |+ field (bytes 64) (fun t -> t.v) |> sealr end - module MK_HASH_32 () = struct + module MK_HASH_32 () : sig + type t = private { hash: string } + + val of_octets : string -> t + val bin : t Bin.t + end = struct type t = { hash: string } + let of_octets s = + match String.length s = 32 with + | false -> Fmt.failwith "SHA256 failure: data is not 32 bytes" + | true -> + let hash = Digestif.SHA256.(to_raw_string (digest_string s)) in + { hash } + let bin = let open Bin in record (fun hash -> { hash }) @@ -81,15 +104,56 @@ module UTIL = struct |> sealr end - module MK_HASH_64 () = struct + module MK_HASH_64 () : sig + type t = private { hash: string } + + val of_string : string -> t + val bin : t Bin.t + end = struct type t = { hash: string } + let of_string s = + match String.length s = 64 with + | false -> Fmt.failwith "SHA512 failure: data is not 64bytes" + | true -> + let hash = Digestif.SHA512.(to_raw_string (digest_string s)) in + { hash } + let bin = let open Bin in record (fun hash -> { hash }) |+ field (bytes 64) (fun t -> t.hash) |> sealr end + (* + let to_null_terminated s = + let len = String.length s in + let b = Bytes.create (len + 1) in + Bytes.blit_string s 0 b 0 len; + Bytes.set b len '\x00'; + Bytes.unsafe_to_string b + *) + + module HASH_64 : sig + type t + + val hash : string -> t + val bin : t Bin.t + end = struct + type t = { hash: Digestif.SHA512.t } + + let hash s = + let hash = Digestif.SHA512.(digest_string s) in + { hash } + + let hash_bin = + let open Bin in + map (bytes 64) Digestif.SHA512.of_raw_string Digestif.SHA512.to_raw_string + + let bin = + let open Bin in + record (fun hash -> { hash }) |+ field hash_bin (fun t -> t.hash) |> sealr + end end open UTIL @@ -106,6 +170,78 @@ module TimestampNBO = MK_TIME_NBO () (* -- Cryptographic primitives -- *) +(* GNUNET_CRYPTO format *) +module GNUNET_RsaPublicKey = struct + (* libgnuutil format: + https://docs.gnunet.org/doxygen/d9/dbe/structGNUNET__CRYPTO__RsaPublicKeyHeaderP.html + https://docs.gnunet.org/doxygen/d6/d70/group__libgnunetutil.html#ga9c99a81e8cd649c1c925d23211a0738f + https://www.gnupg.org/documentation/manuals/gcrypt/MPI-formats.html + + format: + - rsa header + - modulus + - public_exponent + + integer in big-endian format (MSB first). + Leading zeroes are stripped unless they are required to keep a value positive. + *) + type header = { + n_len: int; + e_len: int; + } + + type t = { + header: header; + n: Z.t; + e: Z.t; + } + + (* need to strip leading zeros or something? *) + let z_to_bigendian_bits v = + let s = Z.to_bits v in + let len = String.length s in + let s = String.init len (fun i -> s.[len - 1 - i]) in + s + + let header_bin = + let open Bin in + record (fun n_len e_len -> { n_len; e_len }) + |+ field beint16 (fun t -> t.n_len) + |+ field beint16 (fun t -> t.e_len) + |> sealr + + (* note: this one has a dynamic sizeof *) + let bin = + let open Bin in + record (fun header n e -> + let n = Z.of_bits n in + let e = Z.of_bits e in + { header; n; e }) + |+ field header_bin (fun t -> t.header) + (* TODO + Z.to_bits is in little endian but we need it in big endian *) + (* TODO + here it should not be [cstring] but [bytes t.header.n_len] *) + |+ field cstring (fun t -> z_to_bigendian_bits t.n) + |+ field cstring (fun t -> z_to_bigendian_bits t.e) + |> sealr + + let of_pub ({ n; e } : Mirage_crypto_pk.Rsa.pub) = + let header = { n_len= Z.size n; e_len= Z.size e } in + let t = { header; n; e } in + t +end + +module DenominationHash = struct + include HASH_64 + + let mk (pub : Mirage_crypto_pk.Rsa.pub) = + pub + |> GNUNET_RsaPublicKey.of_pub + |> Bin.to_string GNUNET_RsaPublicKey.bin + |> hash +end + (* --- Hashes --- *) module ShortHashCode = MK_HASH_32 () @@ -118,7 +254,6 @@ module FullPaytoHash = MK_HASH_32 () (* Hash over a normalized payto://-URI, including all optional fields and also with account-part canonicalized (so no BIC). *) module NormalizedPaytoHash = MK_HASH_32 () -module DenominationHash = MK_HASH_64 () module PrivateContractHash = MK_HASH_64 () module ExtensionsPolicyHash = MK_HASH_64 () module MerchantWireHash = MK_HASH_64 () @@ -182,61 +317,6 @@ module EncryptedLinkSecretP = MK_64 () type DenominationBlindingKeyP = string; *) module DenominationBlindingKeyP = MK_32 () -(* GNUNET_CRYPTO format *) -module RsaPublicKey = struct - (* libgnuutil format: - https://docs.gnunet.org/doxygen/d9/dbe/structGNUNET__CRYPTO__RsaPublicKeyHeaderP.html - https://docs.gnunet.org/doxygen/d6/d70/group__libgnunetutil.html#ga9c99a81e8cd649c1c925d23211a0738f - https://www.gnupg.org/documentation/manuals/gcrypt/MPI-formats.html - - format: - - rsa header - - modulus - - public_exponent - - integer in big-endian format (MSB first). - Leading zeroes are stripped unless they are required to keep a value positive. - *) - type header = { - n_len: int; - e_len: int; - } - - type t = { - header: header; - n: Z.t; - e: Z.t; - } - - (* need to strip leading zeros or something? *) - let z_to_bigendian_bits v = - let s = Z.to_bits v in - let len = String.length s in - let s = String.init len (fun i -> s.[len - 1 - i]) in - s - - let header_bin = - let open Bin in - record (fun n_len e_len -> { n_len; e_len }) - |+ field beint16 (fun t -> t.n_len) - |+ field beint16 (fun t -> t.e_len) - |> sealr - - (* note: this one has a dynamic sizeof *) - let bin = - let open Bin in - record (fun header n e -> - let n = Z.of_bits n in - let e = Z.of_bits e in - { header; n; e }) - |+ field header_bin (fun t -> t.header) - (* TODO - Z.to_bits is in little endian but we need it in big endian *) - |+ field cstring (fun t -> z_to_bigendian_bits t.n) - |+ field cstring (fun t -> z_to_bigendian_bits t.e) - |> sealr -end - (* --- Various --- *) module RefreshCommitmentP = MK_64 () diff --git a/src/dune b/src/dune index 168b23c8..8126b6ec 100644 --- a/src/dune +++ b/src/dune @@ -18,6 +18,7 @@ angstrom zarith ; mirage-crypto + digestif duration vif fmt diff --git a/src/management.ml b/src/management.ml index 6fbfc9ee..7a43c5b6 100644 --- a/src/management.ml +++ b/src/management.ml @@ -28,16 +28,8 @@ let mk_future_denom denom_secmod_sign_f in let denom_secmod_sig = let open Binary_formats in - let h_denom_pub = - (* TODO hash *) - let hash = pub |> Types.RsaPublicKey.to_b32 in - DenominationHash.{ hash } - in - let h_section_name = - (* TODO hash *) - let hash = section_name in - HashCode.{ hash } - in + let h_denom_pub = DenominationHash.mk pub in + let h_section_name = HashCode.of_string section_name in let anchor_time = TimeAbsoluteNBO.{ v= Util.ptime_to_int64_us stamp_start } in diff --git a/src/types.ml b/src/types.ml index 73c500dd..8b97da6c 100644 --- a/src/types.ml +++ b/src/types.ml @@ -134,7 +134,7 @@ 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 open Binary_formats.GNUNET_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 @@ -143,7 +143,7 @@ module RsaPublicKey = struct let of_b32 s = let open Syntax in let* s = B32.decode s in - let* v = Util.bin_of_string Binary_formats.RsaPublicKey.bin s in + let* v = Util.bin_of_string Binary_formats.GNUNET_RsaPublicKey.bin s in let+ v = Mirage_crypto_pk.Rsa.pub ~n:v.n ~e:v.e |> unwrap_err_msg in v diff --git a/test/test.ml b/test/test.ml index 8d4bd866..26a811ac 100644 --- a/test/test.ml +++ b/test/test.ml @@ -75,6 +75,8 @@ let () = check_bad ", \"foo\""; () +(* + let () = let open Binary_formats.WithdrawConfirmationPS in let str64 = String.init 64 (fun i -> Char.unsafe_chr (i + 1)) in @@ -88,3 +90,5 @@ let () = Printf.printf "%s" raw_str; *) () + + *)