block-padding: merge Padding and RawPadding traits (#1217)

Author: newpavlov

block-padding/CHANGELOG.md

@@ -8,9 +8,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 - Migrated from `generic-array` to `hybrid-array` ([#944])
 - Edition changed to 2024 and MSRV bumped to 1.85 ([#1149])
+- Merged `RawPadding` and `Padding` traits ([#1217])
+
+### Removed
+- `Block` type alias ([#1217])
 
 [#944]: https://github.com/RustCrypto/utils/pull/944
 [#1149]: https://github.com/RustCrypto/utils/pull/1149
+[#1217]: https://github.com/RustCrypto/utils/pull/1217
 
 ## 0.3.3 (2023-04-02)
 ### Added

block-padding/src/lib.rs

@@ -26,8 +26,8 @@ pub enum PadType {
     NoPadding,
 }
 
-/// Trait for padding messages divided into blocks of arbitrary size
-pub trait RawPadding {
+/// Trait for messages padding algorithms.
+pub trait Padding {
     /// Padding type
     const TYPE: PadType;
 
@@ -43,33 +43,30 @@ pub trait RawPadding {
     ///
     /// Returns `Err(UnpadError)` if the block contains malformed padding.
     fn raw_unpad(block: &[u8]) -> Result<&[u8], UnpadError>;
-}
-
-/// Block size.
-pub type Block<B> = Array<u8, B>;
-
-/// Trait for padding messages divided into blocks
-pub trait Padding<BlockSize: ArraySize> {
-    /// Padding type
-    const TYPE: PadType;
 
     /// Pads `block` filled with data up to `pos` (i.e length of a message
     /// stored in the block is equal to `pos`).
     ///
     /// # Panics
     /// If `pos` is bigger than `BlockSize`. Most padding algorithms also
     /// panic if they are equal.
-    fn pad(block: &mut Block<BlockSize>, pos: usize);
+    fn pad<BlockSize: ArraySize>(block: &mut Array<u8, BlockSize>, pos: usize) {
+        Self::raw_pad(block.as_mut_slice(), pos);
+    }
 
     /// Unpad data in the `block`.
     ///
     /// Returns `Err(UnpadError)` if the block contains malformed padding.
-    fn unpad(block: &Block<BlockSize>) -> Result<&[u8], UnpadError>;
+    fn unpad<BlockSize: ArraySize>(block: &Array<u8, BlockSize>) -> Result<&[u8], UnpadError> {
+        Self::raw_unpad(block.as_slice())
+    }
 
     /// Unpad data in the `blocks`.
     ///
     /// Returns `Err(UnpadError)` if the block contains malformed padding.
-    fn unpad_blocks(blocks: &[Block<BlockSize>]) -> Result<&[u8], UnpadError> {
+    fn unpad_blocks<BlockSize: ArraySize>(
+        blocks: &[Array<u8, BlockSize>],
+    ) -> Result<&[u8], UnpadError> {
         let bs = BlockSize::USIZE;
         let res_len = match (blocks.last(), Self::TYPE) {
             (_, PadType::NoPadding) => bs * blocks.len(),
@@ -89,23 +86,6 @@ pub trait Padding<BlockSize: ArraySize> {
     }
 }
 
-impl<T, B: ArraySize> Padding<B> for T
-where
-    T: RawPadding,
-{
-    const TYPE: PadType = T::TYPE;
-
-    #[inline]
-    fn pad(block: &mut Block<B>, pos: usize) {
-        T::raw_pad(block.as_mut_slice(), pos);
-    }
-
-    #[inline]
-    fn unpad(block: &Block<B>) -> Result<&[u8], UnpadError> {
-        T::raw_unpad(block.as_slice())
-    }
-}
-
 /// Pad block with zeros.
 ///
 /// ```
@@ -127,7 +107,7 @@ where
 #[derive(Clone, Copy, Debug)]
 pub struct ZeroPadding;
 
-impl RawPadding for ZeroPadding {
+impl Padding for ZeroPadding {
     const TYPE: PadType = PadType::Ambiguous;
 
     #[inline]
@@ -189,7 +169,7 @@ impl Pkcs7 {
     }
 }
 
-impl RawPadding for Pkcs7 {
+impl Padding for Pkcs7 {
     const TYPE: PadType = PadType::Reversible;
 
     #[inline]
@@ -231,7 +211,7 @@ impl RawPadding for Pkcs7 {
 #[derive(Clone, Copy, Debug)]
 pub struct Iso10126;
 
-impl RawPadding for Iso10126 {
+impl Padding for Iso10126 {
     const TYPE: PadType = PadType::Reversible;
 
     #[inline]
@@ -266,7 +246,7 @@ impl RawPadding for Iso10126 {
 #[derive(Clone, Copy, Debug)]
 pub struct AnsiX923;
 
-impl RawPadding for AnsiX923 {
+impl Padding for AnsiX923 {
     const TYPE: PadType = PadType::Reversible;
 
     #[inline]
@@ -320,7 +300,7 @@ impl RawPadding for AnsiX923 {
 #[derive(Clone, Copy, Debug)]
 pub struct Iso7816;
 
-impl RawPadding for Iso7816 {
+impl Padding for Iso7816 {
     const TYPE: PadType = PadType::Reversible;
 
     #[inline]
@@ -369,7 +349,7 @@ impl RawPadding for Iso7816 {
 #[derive(Clone, Copy, Debug)]
 pub struct NoPadding;
 
-impl RawPadding for NoPadding {
+impl Padding for NoPadding {
     const TYPE: PadType = PadType::NoPadding;
 
     #[inline]

inout/src/reserved.rs

@@ -155,7 +155,7 @@ impl<'inp, 'out> InOutBufReserved<'inp, 'out, u8> {
     #[inline(always)]
     pub fn into_padded_blocks<P, BS>(self) -> Result<PaddedInOutBuf<'inp, 'out, BS>, PadError>
     where
-        P: Padding<BS>,
+        P: Padding,
         BS: ArraySize,
     {
         let bs = BS::USIZE;