skein: fix implementation for output sizes not multiple of 8 (#682)

Author: newpavlov

skein/CHANGELOG.md

@@ -5,7 +5,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## 0.1.0 (2023-06-09)
+## 0.1.1 (2025-04-23)
+### Fixed
+- Implementation for output sizes not multiple of 8 ([#682])
+
+[#682]: https://github.com/RustCrypto/hashes/pull/682
+
+## 0.1.0 (2023-06-09) [YANKED]
 - Initial release ([#483])
 
 [#483]: https://github.com/RustCrypto/hashes/pull/483

skein/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "skein"
-version = "0.1.0"
+version = "0.1.1"
 description = "Skein hash functions"
 authors = ["RustCrypto Developers"]
 license = "MIT OR Apache-2.0"

skein/src/lib.rs

@@ -156,8 +156,8 @@ macro_rules! define_hasher {
                     block[..8].copy_from_slice(&(i as u64).to_le_bytes());
                     Self::process_block(&mut ctr, &block, 8);
 
-                    for (src, dst) in ctr.x.iter().zip(chunk.chunks_exact_mut(8)) {
-                        dst.copy_from_slice(&src.to_le_bytes());
+                    for (src, dst) in ctr.x.iter().zip(chunk.chunks_mut(8)) {
+                        dst.copy_from_slice(&src.to_le_bytes()[..dst.len()]);
                     }
                 }
             }

skein/tests/lib.rs

@@ -1,7 +1,8 @@
+use hex_literal::hex;
 use skein::{
-    consts::{U128, U32, U64},
+    consts::{U128, U32, U64, U7},
     digest::{dev::fixed_test, new_test},
-    Skein1024, Skein256, Skein512,
+    Digest, Skein1024, Skein256, Skein512,
 };
 
 new_test!(skein256_32, "skein256_32", Skein256<U32>, fixed_test);
@@ -11,3 +12,15 @@ new_test!(skein512_64, "skein512_64", Skein512<U64>, fixed_test);
 new_test!(skein1024_32, "skein1024_32", Skein1024<U32>, fixed_test);
 new_test!(skein1024_64, "skein1024_64", Skein1024<U64>, fixed_test);
 new_test!(skein1024_128, "skein1024_128", Skein1024<U128>, fixed_test);
+
+/// Regression tests for https://github.com/RustCrypto/hashes/issues/681
+#[test]
+fn skein_uncommon_sizes() {
+    let s = "hello world";
+    let h = Skein256::<U7>::digest(s);
+    assert_eq!(h[..], hex!("31bffb70f5dafe")[..]);
+    let h = Skein512::<U7>::digest(s);
+    assert_eq!(h[..], hex!("ee6004efedd69c")[..]);
+    let h = Skein1024::<U7>::digest(s);
+    assert_eq!(h[..], hex!("a2808b638681c6")[..]);
+}