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Diffstat (limited to '')
| -rw-r--r-- | vendor/block-padding/src/lib.rs | 323 |
1 files changed, 0 insertions, 323 deletions
diff --git a/vendor/block-padding/src/lib.rs b/vendor/block-padding/src/lib.rs deleted file mode 100644 index 5c4c8c3b6..000000000 --- a/vendor/block-padding/src/lib.rs +++ /dev/null @@ -1,323 +0,0 @@ -//! Padding and unpadding of messages divided into blocks. -//! -//! This crate provides `Padding` trait which provides padding and unpadding -//! operations. Additionally several common padding schemes are available out -//! of the box. -#![no_std] -#![doc(html_logo_url = - "https://raw.githubusercontent.com/RustCrypto/meta/master/logo_small.png")] -extern crate byte_tools; - -use byte_tools::{zero, set}; - -/// Error for indicating failed padding operation -#[derive(Clone, Copy, Debug)] -pub struct PadError; - -/// Error for indicating failed unpadding operation -#[derive(Clone, Copy, Debug)] -pub struct UnpadError; - -/// Trait for padding messages divided into blocks -pub trait Padding { - /// Pads `block` filled with data up to `pos`. - /// - /// `pos` should be inside of the block and block must not be full, i.e. - /// `pos < block.len()` must be true. Otherwise method will return - /// `PadError`. Some potentially irreversible padding schemes can allow - /// padding of the full block, in this case aforementioned condition is - /// relaxed to `pos <= block.len()`. - fn pad_block(block: &mut [u8], pos: usize) -> Result<(), PadError>; - - /// Pads message with length `pos` in the provided buffer. - /// - /// `&buf[..pos]` is perceived as the message, the buffer must contain - /// enough leftover space for padding: `block_size - (pos % block_size)` - /// extra bytes must be available. Otherwise method will return - /// `PadError`. - fn pad(buf: &mut [u8], pos: usize, block_size: usize) - -> Result<&mut [u8], PadError> - { - let bs = block_size * (pos / block_size); - if buf.len() < bs || buf.len() - bs < block_size { Err(PadError)? } - Self::pad_block(&mut buf[bs..bs+block_size], pos - bs)?; - Ok(&mut buf[..bs+block_size]) - } - - /// Unpad given `data` by truncating it according to the used padding. - /// In case of the malformed padding will return `UnpadError` - fn unpad(data: &[u8]) -> Result<&[u8], UnpadError>; -} - -/// Pad block with zeros. -/// -/// ``` -/// use block_padding::{ZeroPadding, Padding}; -/// -/// let msg = b"test"; -/// let n = msg.len(); -/// let mut buffer = [0xff; 16]; -/// buffer[..n].copy_from_slice(msg); -/// let padded_msg = ZeroPadding::pad(&mut buffer, n, 8).unwrap(); -/// assert_eq!(padded_msg, b"test\x00\x00\x00\x00"); -/// assert_eq!(ZeroPadding::unpad(&padded_msg).unwrap(), msg); -/// ``` -/// ``` -/// # use block_padding::{ZeroPadding, Padding}; -/// # let msg = b"test"; -/// # let n = msg.len(); -/// # let mut buffer = [0xff; 16]; -/// # buffer[..n].copy_from_slice(msg); -/// let padded_msg = ZeroPadding::pad(&mut buffer, n, 2).unwrap(); -/// assert_eq!(padded_msg, b"test"); -/// assert_eq!(ZeroPadding::unpad(&padded_msg).unwrap(), msg); -/// ``` -/// -/// Note that zero padding may not be reversible if the original message ends -/// with one or more zero bytes. -pub enum ZeroPadding{} - -impl Padding for ZeroPadding { - fn pad_block(block: &mut [u8], pos: usize) -> Result<(), PadError> { - if pos > block.len() { Err(PadError)? } - zero(&mut block[pos..]); - Ok(()) - } - - fn pad(buf: &mut [u8], pos: usize, block_size: usize) - -> Result<&mut [u8], PadError> - { - if pos % block_size == 0 { - Ok(&mut buf[..pos]) - } else { - let bs = block_size * (pos / block_size); - let be = bs + block_size; - if buf.len() < be { Err(PadError)? } - Self::pad_block(&mut buf[bs..be], pos - bs)?; - Ok(&mut buf[..be]) - } - } - - fn unpad(data: &[u8]) -> Result<&[u8], UnpadError> { - let mut n = data.len() - 1; - while n != 0 { - if data[n] != 0 { - break; - } - n -= 1; - } - Ok(&data[..n+1]) - } -} - -/// Pad block with bytes with value equal to the number of bytes added. -/// -/// PKCS#7 described in the [RFC 5652](https://tools.ietf.org/html/rfc5652#section-6.3). -/// -/// ``` -/// use block_padding::{Pkcs7, Padding}; -/// -/// let msg = b"test"; -/// let n = msg.len(); -/// let mut buffer = [0xff; 8]; -/// buffer[..n].copy_from_slice(msg); -/// let padded_msg = Pkcs7::pad(&mut buffer, n, 8).unwrap(); -/// assert_eq!(padded_msg, b"test\x04\x04\x04\x04"); -/// assert_eq!(Pkcs7::unpad(&padded_msg).unwrap(), msg); -/// ``` -/// ``` -/// # use block_padding::{Pkcs7, Padding}; -/// # let msg = b"test"; -/// # let n = msg.len(); -/// # let mut buffer = [0xff; 8]; -/// # buffer[..n].copy_from_slice(msg); -/// let padded_msg = Pkcs7::pad(&mut buffer, n, 2).unwrap(); -/// assert_eq!(padded_msg, b"test\x02\x02"); -/// assert_eq!(Pkcs7::unpad(&padded_msg).unwrap(), msg); -/// ``` -/// ``` -/// # use block_padding::{Pkcs7, Padding}; -/// let mut buffer = [0xff; 5]; -/// assert!(Pkcs7::pad(&mut buffer, 4, 2).is_err()); -/// ``` -/// ``` -/// # use block_padding::{Pkcs7, Padding}; -/// # let buffer = [0xff; 16]; -/// assert!(Pkcs7::unpad(&buffer).is_err()); -/// ``` -/// -/// In addition to conditions stated in the `Padding` trait documentation, -/// `pad_block` will return `PadError` if `block.len() > 255`, and in case of -/// `pad` if `block_size > 255`. -pub enum Pkcs7{} - -impl Padding for Pkcs7 { - fn pad_block(block: &mut [u8], pos: usize) -> Result<(), PadError> { - if block.len() > 255 { Err(PadError)? } - if pos >= block.len() { Err(PadError)? } - let n = block.len() - pos; - set(&mut block[pos..], n as u8); - Ok(()) - } - - fn unpad(data: &[u8]) -> Result<&[u8], UnpadError> { - if data.is_empty() { Err(UnpadError)? } - let l = data.len(); - let n = data[l-1]; - if n == 0 || n as usize > l { Err(UnpadError)? } - for v in &data[l-n as usize..l-1] { - if *v != n { Err(UnpadError)? } - } - Ok(&data[..l - n as usize]) - } -} - -/// Pad block with zeros except the last byte which will be set to the number -/// bytes. -/// -/// ``` -/// use block_padding::{AnsiX923, Padding}; -/// -/// let msg = b"test"; -/// let n = msg.len(); -/// let mut buffer = [0xff; 16]; -/// buffer[..n].copy_from_slice(msg); -/// let padded_msg = AnsiX923::pad(&mut buffer, n, 8).unwrap(); -/// assert_eq!(padded_msg, b"test\x00\x00\x00\x04"); -/// assert_eq!(AnsiX923::unpad(&padded_msg).unwrap(), msg); -/// ``` -/// ``` -/// # use block_padding::{AnsiX923, Padding}; -/// # let msg = b"test"; -/// # let n = msg.len(); -/// # let mut buffer = [0xff; 16]; -/// # buffer[..n].copy_from_slice(msg); -/// let padded_msg = AnsiX923::pad(&mut buffer, n, 2).unwrap(); -/// assert_eq!(padded_msg, b"test\x00\x02"); -/// assert_eq!(AnsiX923::unpad(&padded_msg).unwrap(), msg); -/// ``` -/// ``` -/// # use block_padding::{AnsiX923, Padding}; -/// # let buffer = [0xff; 16]; -/// assert!(AnsiX923::unpad(&buffer).is_err()); -/// ``` -/// -/// In addition to conditions stated in the `Padding` trait documentation, -/// `pad_block` will return `PadError` if `block.len() > 255`, and in case of -/// `pad` if `block_size > 255`. -pub enum AnsiX923{} - -impl Padding for AnsiX923 { - fn pad_block(block: &mut [u8], pos: usize) -> Result<(), PadError>{ - if block.len() > 255 { Err(PadError)? } - if pos >= block.len() { Err(PadError)? } - let bs = block.len(); - zero(&mut block[pos..bs-1]); - block[bs-1] = (bs - pos) as u8; - Ok(()) - } - - fn unpad(data: &[u8]) -> Result<&[u8], UnpadError> { - if data.is_empty() { Err(UnpadError)? } - let l = data.len(); - let n = data[l-1] as usize; - if n == 0 || n > l { - return Err(UnpadError) - } - for v in &data[l-n..l-1] { - if *v != 0 { Err(UnpadError)? } - } - Ok(&data[..l-n]) - } -} - -/// Pad block with byte sequence `\x80 00...00 00`. -/// -/// ``` -/// use block_padding::{Iso7816, Padding}; -/// -/// let msg = b"test"; -/// let n = msg.len(); -/// let mut buffer = [0xff; 16]; -/// buffer[..n].copy_from_slice(msg); -/// let padded_msg = Iso7816::pad(&mut buffer, n, 8).unwrap(); -/// assert_eq!(padded_msg, b"test\x80\x00\x00\x00"); -/// assert_eq!(Iso7816::unpad(&padded_msg).unwrap(), msg); -/// ``` -/// ``` -/// # use block_padding::{Iso7816, Padding}; -/// # let msg = b"test"; -/// # let n = msg.len(); -/// # let mut buffer = [0xff; 16]; -/// # buffer[..n].copy_from_slice(msg); -/// let padded_msg = Iso7816::pad(&mut buffer, n, 2).unwrap(); -/// assert_eq!(padded_msg, b"test\x80\x00"); -/// assert_eq!(Iso7816::unpad(&padded_msg).unwrap(), msg); -/// ``` -pub enum Iso7816{} - -impl Padding for Iso7816 { - fn pad_block(block: &mut [u8], pos: usize) -> Result<(), PadError> { - if pos >= block.len() { Err(PadError)? } - block[pos] = 0x80; - zero(&mut block[pos+1..]); - Ok(()) - } - - fn unpad(data: &[u8]) -> Result<&[u8], UnpadError> { - if data.is_empty() { Err(UnpadError)? } - let mut n = data.len() - 1; - while n != 0 { - if data[n] != 0 { break; } - n -= 1; - } - if data[n] != 0x80 { Err(UnpadError)? } - Ok(&data[..n]) - } -} - -/// Don't pad the data. Useful for key wrapping. Padding will fail if the data cannot be -/// fitted into blocks without padding. -/// -/// ``` -/// use block_padding::{NoPadding, Padding}; -/// -/// let msg = b"test"; -/// let n = msg.len(); -/// let mut buffer = [0xff; 16]; -/// buffer[..n].copy_from_slice(msg); -/// let padded_msg = NoPadding::pad(&mut buffer, n, 4).unwrap(); -/// assert_eq!(padded_msg, b"test"); -/// assert_eq!(NoPadding::unpad(&padded_msg).unwrap(), msg); -/// ``` -/// ``` -/// # use block_padding::{NoPadding, Padding}; -/// # let msg = b"test"; -/// # let n = msg.len(); -/// # let mut buffer = [0xff; 16]; -/// # buffer[..n].copy_from_slice(msg); -/// let padded_msg = NoPadding::pad(&mut buffer, n, 2).unwrap(); -/// assert_eq!(padded_msg, b"test"); -/// assert_eq!(NoPadding::unpad(&padded_msg).unwrap(), msg); -/// ``` -pub enum NoPadding {} - -impl Padding for NoPadding { - fn pad_block(block: &mut [u8], pos: usize) -> Result<(), PadError> { - if pos % block.len() != 0 { - Err(PadError)? - } - Ok(()) - } - - fn pad(buf: &mut [u8], pos: usize, block_size: usize) -> Result<&mut [u8], PadError> { - if pos % block_size != 0 { - Err(PadError)? - } - Ok(&mut buf[..pos]) - } - - fn unpad(data: &[u8]) -> Result<&[u8], UnpadError> { - Ok(data) - } -} |