rewrite aesenc to work in-place

speeds up encryption by a bit

1 files changed, 19 insertions, 31 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 210c7f8..13abce7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -247,44 +247,32 @@ impl Aez {
     }
 }
 
-fn aesenc(mut block: Block, key: &Block) -> block::Block {
+fn aesenc(block: &mut Block, key: &Block){
     aes::hazmat::cipher_round((&mut block.0).into(), &key.0.into());
-    block
 }
 
 fn aes4(keys: &[&Block; 5], block: &Block) -> Block {
-    aesenc(
-        aesenc(aesenc(aesenc(*block ^ *keys[0], keys[1]), keys[2]), keys[3]),
-        keys[4],
-    )
+    let mut r = *block ^ *keys[0];
+    aesenc(&mut r, keys[1]);
+    aesenc(&mut r, keys[2]);
+    aesenc(&mut r, keys[3]);
+    aesenc(&mut r, keys[4]);
+    r
 }
 
 fn aes10(keys: &[&Block; 11], block: &Block) -> Block {
-    aesenc(
-        aesenc(
-            aesenc(
-                aesenc(
-                    aesenc(
-                        aesenc(
-                            aesenc(
-                                aesenc(
-                                    aesenc(aesenc(*block ^ *keys[0], keys[1]), keys[2]),
-                                    keys[3],
-                                ),
-                                keys[4],
-                            ),
-                            keys[5],
-                        ),
-                        keys[6],
-                    ),
-                    keys[7],
-                ),
-                keys[8],
-            ),
-            keys[9],
-        ),
-        keys[10],
-    )
+    let mut r = *block ^ *keys[0];
+    aesenc(&mut r, keys[1]);
+    aesenc(&mut r, keys[2]);
+    aesenc(&mut r, keys[3]);
+    aesenc(&mut r, keys[4]);
+    aesenc(&mut r, keys[5]);
+    aesenc(&mut r, keys[6]);
+    aesenc(&mut r, keys[7]);
+    aesenc(&mut r, keys[8]);
+    aesenc(&mut r, keys[9]);
+    aesenc(&mut r, keys[10]);
+    r
 }
 
 fn extract(key: &[u8]) -> [u8; 48] {