From f692025c75f3cf3b94b3061e65aeb84de754192f Mon Sep 17 00:00:00 2001
From: Brian Smith <brian@briansmith.org>
Date: Thu, 12 Oct 2023 22:28:07 -0700
Subject: [PATCH] Chacha20-Poly1305-OpenSSH: Remove use of `ChunksFixed`.

Take a step towards removing the `unsafe` in `ChunksFixed`'s implementation.
---
 src/aead/chacha20_poly1305_openssh.rs | 10 ++++------
 src/polyfill/chunks_fixed.rs          |  1 -
 2 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/src/aead/chacha20_poly1305_openssh.rs b/src/aead/chacha20_poly1305_openssh.rs
index b8aa999fbc..015d41787d 100644
--- a/src/aead/chacha20_poly1305_openssh.rs
+++ b/src/aead/chacha20_poly1305_openssh.rs
@@ -32,9 +32,7 @@
 use super::{
     chacha::{self, *},
     chacha20_poly1305::derive_poly1305_key,
-    cpu, poly1305,
-    polyfill::ChunksFixed,
-    Nonce, Tag,
+    cpu, poly1305, Nonce, Tag,
 };
 use crate::{constant_time, error};
 
@@ -152,10 +150,10 @@ struct Key {
 impl Key {
     fn new(key_material: &[u8; KEY_LEN], cpu_features: cpu::Features) -> Self {
         // The first half becomes K_2 and the second half becomes K_1.
-        let &[k_2, k_1]: &[[u8; chacha::KEY_LEN]; 2] = key_material.chunks_fixed();
+        let (k_2, k_1) = key_material.split_at(chacha::KEY_LEN);
         Self {
-            k_1: chacha::Key::new(k_1, cpu_features),
-            k_2: chacha::Key::new(k_2, cpu_features),
+            k_1: chacha::Key::new(k_1.try_into().unwrap(), cpu_features),
+            k_2: chacha::Key::new(k_2.try_into().unwrap(), cpu_features),
         }
     }
 }
diff --git a/src/polyfill/chunks_fixed.rs b/src/polyfill/chunks_fixed.rs
index ac6f180640..4d3f703202 100644
--- a/src/polyfill/chunks_fixed.rs
+++ b/src/polyfill/chunks_fixed.rs
@@ -27,5 +27,4 @@ macro_rules! define_chunks_fixed {
 }
 
 // Sorted by the first value, then the second value.
-define_chunks_fixed!(64, 32);
 define_chunks_fixed!(80, 20);