From f75a3ccb34de9abf2d01f8f3e2e1567f5ad0c508 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=B2=81=E6=A0=91=E4=BA=BA?= <lu.shuren@um-react.app>
Date: Sun, 15 Sep 2024 15:40:03 +0100
Subject: [PATCH] [qmc2/rc4] refactor: create box of slice instead of convert
 later

---
 um_crypto/qmc/src/v2_rc4/cipher.rs | 6 +++---
 um_crypto/qmc/src/v2_rc4/rc4.rs    | 7 +++++--
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/um_crypto/qmc/src/v2_rc4/cipher.rs b/um_crypto/qmc/src/v2_rc4/cipher.rs
index 40e9d01..ad63fba 100644
--- a/um_crypto/qmc/src/v2_rc4/cipher.rs
+++ b/um_crypto/qmc/src/v2_rc4/cipher.rs
@@ -17,13 +17,13 @@ pub struct QMC2RC4 {
 impl QMC2RC4 {
     pub fn new(key: &[u8]) -> Self {
         let mut rc4 = RC4::new(key);
-        let mut key_stream = [0u8; RC4_STREAM_CACHE_SIZE];
-        rc4.derive(&mut key_stream);
+        let mut key_stream = Box::new([0u8; RC4_STREAM_CACHE_SIZE]);
+        rc4.derive(&mut key_stream[..]);
 
         Self {
             hash: hash(key),
             key: key.into(),
-            key_stream: key_stream.into(),
+            key_stream,
         }
     }
 
diff --git a/um_crypto/qmc/src/v2_rc4/rc4.rs b/um_crypto/qmc/src/v2_rc4/rc4.rs
index c7724e1..b273b52 100644
--- a/um_crypto/qmc/src/v2_rc4/rc4.rs
+++ b/um_crypto/qmc/src/v2_rc4/rc4.rs
@@ -42,8 +42,11 @@ impl RC4 {
         self.state[index]
     }
 
-    pub fn derive(&mut self, buffer: &mut [u8]) {
-        for item in buffer.iter_mut() {
+    pub fn derive<T>(&mut self, buffer: &mut T)
+    where
+        T: AsMut<[u8]> + ?Sized,
+    {
+        for item in buffer.as_mut().iter_mut() {
             *item ^= self.generate();
         }
     }