Struct ADFGVX 

pub struct ADFGVX { /* private fields */ }

ADFGVX cipher combining Polybius square substitution with columnar transposition.

This structure holds the two components of the ADFGVX cipher:

• A Polybius square cipher using the letters A, D, F, G, V, X
• A columnar transposition cipher for the second encryption stage

Implementations

impl ADFGVX

pub fn new(key1: &str, key2: &str) -> Result<Self>

Creates a new ADFGVX cipher with the given keys.

Arguments

• key1 - The keyword for the Polybius square substitution (should contain unique letters)
• key2 - The keyword for the columnar transposition (defines column order)

Returns

Returns Ok(ADFGVX) if both keys are valid, or Err(String) with an error message if either key is invalid (e.g., empty or contains invalid characters).

Examples

let cipher = ADFGVX::new("PORTABLE", "SUBWAY").unwrap();

Errors

Returns an error if:

• Either key is empty
• The keys contain invalid characters
• The Polybius square or transposition cipher cannot be initialized

Trait Implementations

impl Block for ADFGVX

fn block_size(&self) -> usize

Returns the block size for the cipher.

The block size is determined by the transposition cipher’s block size, which is twice the length of the transposition key (since each character is first encoded into two ADFGVX characters).

Returns

The block size in bytes.

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

Encrypts plaintext using the ADFGVX cipher.

The encryption is performed in two stages:

1. Each plaintext character is substituted using the Polybius square, producing two ADFGVX characters (row and column coordinates)
2. The resulting bigrammatic text is transposed using columnar transposition

Arguments

• dst - Destination buffer for the ciphertext (must be large enough)
• src - Source plaintext bytes to encrypt

Returns

The number of bytes written to dst.

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

Decrypts ciphertext using the ADFGVX cipher.

The decryption is performed by reversing the two encryption stages:

1. The columnar transposition is reversed to recover the bigrammatic text
2. Each pair of ADFGVX characters is converted back to the original character using the Polybius square

Arguments

• dst - Destination buffer for the plaintext (must be large enough)
• src - Source ciphertext bytes to decrypt

Returns

The number of bytes written to dst.

impl Debug for ADFGVX

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.