From bf5a408e852c79f3373da59c7675c13e53434ff6 Mon Sep 17 00:00:00 2001 From: Daniel Schadt Date: Thu, 4 Sep 2025 22:04:48 +0200 Subject: inline pad_to_blocks I like the way with chunks_exact more, as we get the remainder for free and we don't have to do the chunk.len() dance --- src/lib.rs | 26 +++++++++----------------- 1 file changed, 9 insertions(+), 17 deletions(-) (limited to 'src/lib.rs') diff --git a/src/lib.rs b/src/lib.rs index 95c1622..41b8d72 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -688,16 +688,6 @@ fn cipher_aez_core, T: IntoIterator>( blocks.set_m_y(c_y); } -fn pad_to_blocks(value: &[u8]) -> impl Iterator { - value.chunks(16).map(|chunk| { - if chunk.len() == 16 { - Block::from_slice(chunk) - } else { - Block::from_slice(chunk).pad(chunk.len() * 8) - } - }) -} - fn aez_hash, T: IntoIterator>(aez: &Aez, tweaks: T) -> Block { let mut hash = Block::null(); for (i, tweak) in tweaks.into_iter().enumerate() { @@ -716,15 +706,17 @@ fn aez_hash, T: IntoIterator>(aez: &Aez, tweaks: T) -> hash = hash ^ ej.eval(Block::from_slice(chunk)); } } else { - let blocks = pad_to_blocks(tweak); - for (l, chunk) in blocks.enumerate() { + let blocks = tweak.chunks_exact(16); + let remainder = blocks.remainder(); + + for chunk in blocks { ej.advance(); - if l == tweak.len() / 16 { - hash = hash ^ e(j.try_into().unwrap(), 0, aez, chunk); - } else { - hash = hash ^ ej.eval(chunk); - } + hash = hash ^ ej.eval(Block::from_slice(chunk)); } + + ej.advance(); + let chunk = Block::from_slice(remainder).pad_bytes(remainder.len() as u8); + hash = hash ^ e(j.try_into().unwrap(), 0, aez, chunk); } } hash -- cgit v1.2.3