update kwp to prerelease

.github/workflows/belt-kwp.yml

@@ -22,7 +22,7 @@ jobs:
     strategy:
       matrix:
         rust:
-          - 1.56.0 # MSRV
+          - 1.65.0 # MSRV
           - stable
         target:
           - thumbv7em-none-eabi

Cargo.toml

@@ -6,3 +6,6 @@ members = [
 
 [profile.dev]
 opt-level = 2
+
+#[patch.crates-io]
+#belt-block = { git = "https://github.com/RustCrypto/block-ciphers.git" }

belt-kwp/Cargo.toml

@@ -10,13 +10,13 @@ keywords = ["crypto", "BELT-KW", "KW", "BELT-KWP", "KWP"]
 categories = ["cryptography", "no-std"]
 readme = "README.md"
 edition = "2021"
-rust-version = "1.56"
+rust-version = "1.65"
 
 [dependencies]
-belt-block = "0.1.2"
+belt-block = "=0.2.0-pre.1"
 
 [dev-dependencies]
-hex-literal = "0.3"
+hex-literal = "0.4"
 
 [features]
 alloc = []

belt-kwp/src/lib.rs

@@ -9,6 +9,7 @@
 #![warn(missing_docs, rust_2018_idioms)]
 
 mod error;
+mod utils;
 
 pub use error::{Error, Result};
 
@@ -22,8 +23,7 @@ extern crate std;
 use alloc::vec::Vec;
 use belt_block::{
     belt_wblock_dec, belt_wblock_enc,
-    cipher::{consts::U32, generic_array::GenericArray},
-    to_u32,
+    cipher::{consts::U32, array::Array},
 };
 
 /// Block size for BelT-KWP
@@ -32,8 +32,8 @@ pub const SEMIBLOCK_LEN: usize = 8;
 /// Size of an BelT-block "semiblock" in bytes.
 pub const IV_LEN: usize = 16;
 
-impl From<GenericArray<u8, U32>> for BeltKwp {
-    fn from(kek: GenericArray<u8, U32>) -> Self {
+impl From<Array<u8, U32>> for BeltKwp {
+    fn from(kek: Array<u8, U32>) -> Self {
         BeltKwp::new(&kek)
     }
 }
@@ -49,7 +49,7 @@ impl TryFrom<&[u8]> for BeltKwp {
 
     fn try_from(value: &[u8]) -> Result<Self> {
         if value.len() == 32 {
-            Ok(BeltKwp::new(value.into()))
+            Ok(BeltKwp::new(value.try_into().unwrap()))
         } else {
             Err(Error::InvalidKekSize { size: value.len() })
         }
@@ -66,9 +66,9 @@ pub struct BeltKwp {
 
 impl BeltKwp {
     /// Constructs a new Kek based on the appropriate raw key material.
-    pub fn new(key: &GenericArray<u8, U32>) -> Self {
+    pub fn new(key: &Array<u8, U32>) -> Self {
         Self {
-            key: to_u32::<8>(key),
+            key: utils::to_u32::<8>(key),
         }
     }
 

belt-kwp/src/utils.rs

@@ -0,0 +1,14 @@
+/// Helper function for transforming BelT keys and blocks from a byte array
+/// to an array of `u32`s.
+///
+/// # Panics
+/// If length of `src` is not equal to `4 * N`.
+// #[inline(always)]
+pub(crate) fn to_u32<const N: usize>(src: &[u8]) -> [u32; N] {
+    assert_eq!(src.len(), 4 * N);
+    let mut res = [0u32; N];
+    res.iter_mut()
+        .zip(src.chunks_exact(4))
+        .for_each(|(dst, src)| *dst = u32::from_le_bytes(src.try_into().unwrap()));
+    res
+}