From 5f5f72b6d13f31da3a54569f75d16e85f134451d Mon Sep 17 00:00:00 2001
From: Kamran Khan <kamranrkhan@google.com>
Date: Mon, 30 Nov 2020 02:04:52 -0800
Subject: [PATCH] Use arrayref for converting into ApduHeader

---
 src/ctap/apdu.rs | 6 +++---
 src/lib.rs       | 4 ++++
 src/main.rs      | 3 +++
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/ctap/apdu.rs b/src/ctap/apdu.rs
index 431b18e..fd03f2a 100644
--- a/src/ctap/apdu.rs
+++ b/src/ctap/apdu.rs
@@ -58,8 +58,8 @@ pub struct ApduHeader {
     p2: u8,
 }
 
-impl From<&[u8]> for ApduHeader {
-    fn from(header: &[u8]) -> Self {
+impl From<&[u8; 4]> for ApduHeader {
+    fn from(header: &[u8; 4]) -> Self {
         ApduHeader {
             cla: header[0],
             ins: header[1],
@@ -120,7 +120,7 @@ impl TryFrom<&[u8]> for APDU {
         let (header, payload) = frame.split_at(APDU_HEADER_LEN);
 
         let mut apdu = APDU {
-            header: header.into(),
+            header: array_ref!(header, 0, 4).into(),
             lc: 0x00,
             data: Vec::new(),
             le: 0x00,
diff --git a/src/lib.rs b/src/lib.rs
index d6260c7..07fd02e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -18,3 +18,7 @@ extern crate alloc;
 
 pub mod ctap;
 pub mod embedded_flash;
+
+#[macro_use]
+extern crate arrayref;
+
diff --git a/src/main.rs b/src/main.rs
index 51c8305..ca10c3a 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -19,6 +19,9 @@ extern crate alloc;
 extern crate core;
 extern crate lang_items;
 
+#[macro_use]
+extern crate arrayref;
+
 mod ctap;
 pub mod embedded_flash;