Enum block_padding::Pkcs7

pub enum Pkcs7 {}

Pad block with bytes with value equal to the number of bytes added.

PKCS#7 described in the RFC 5652.

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);

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);

let mut buffer = [0xff; 5];
assert!(Pkcs7::pad(&mut buffer, 4, 2).is_err());

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.

Trait Implementations

impl Padding for Pkcs7

fn pad_block(block: &mut [u8], pos: usize) -> Result<(), PadError>

Pads block filled with data up to pos.

fn unpad(data: &[u8]) -> Result<&[u8], UnpadError>

Unpad given data by truncating it according to the used padding. In case of the malformed padding will return UnpadError

fn pad(
    buf: &mut [u8],
    pos: usize,
    block_size: usize
) -> Result<&mut [u8], PadError>

Pads message with length pos in the provided buffer.