Struct CaesarCipher 

pub struct CaesarCipher { /* private fields */ }

A Caesar cipher implementation.

This struct maintains the shift key for the uppercase English alphabet (A-Z). Characters not in the alphabet are left unchanged.

Fields

• enc - Encryption lookup table mapping A-Z (0-25) to ciphertext
• dec - Decryption lookup table mapping A-Z (0-25) to plaintext

Implementations

impl CaesarCipher

pub fn new(key: i32) -> Self

Creates a new Caesar cipher with the specified shift key.

The key represents how many positions each letter should be shifted in the alphabet.

Arguments

• key - The shift value for the cipher (typically 0-25, but any integer works)

Returns

A new CaesarCipher instance ready for encryption and decryption operations.

Examples

use old_crypto_rs::CaesarCipher;

let cipher = CaesarCipher::new(3); // Classic Caesar cipher with shift of 3

Trait Implementations

impl Block for CaesarCipher

fn block_size(&self) -> usize

Returns the block size for the Caesar cipher.

The Caesar cipher operates on single characters, so the block size is 1.

fn encrypt(&self, dst: &mut [u8], src: &[u8]) -> usize

Encrypts the source data into the destination buffer.

Each byte in the source is shifted by the key value. Characters not in the alphabet (A-Z) are copied unchanged.

Arguments

• dst - Destination buffer for encrypted data (must be at least as large as src)
• src - Source data to encrypt

Returns

The number of bytes written to the destination buffer (equal to src.len()).

fn decrypt(&self, dst: &mut [u8], src: &[u8]) -> usize

Decrypts the source data into the destination buffer.

Each byte in the source is shifted back by the key value. Characters not in the alphabet (A-Z) are copied unchanged.

Arguments

• dst - Destination buffer for decrypted data (must be at least as large as src)
• src - Source data to decrypt

Returns

The number of bytes written to the destination buffer (equal to src.len()).