happy_cracking/crypto/
atbash.rs

1use anyhow::Result;
2use clap::Subcommand;
3
4#[derive(Subcommand)]
5pub enum AtbashAction {
6    #[command(about = "Apply Atbash cipher (A↔Z, B↔Y, ...)")]
7    Transform {
8        #[arg(help = "Input text")]
9        input: String,
10    },
11}
12
13pub fn run(action: AtbashAction) -> Result<()> {
14    match action {
15        AtbashAction::Transform { input } => {
16            println!("{}", transform(&input));
17        }
18    }
19    Ok(())
20}
21
22pub fn transform(input: &str) -> String {
23    let mut bytes = input.as_bytes().to_vec();
24    for b in &mut bytes {
25        if b.is_ascii_uppercase() {
26            *b = b'Z' - (*b - b'A');
27        } else if b.is_ascii_lowercase() {
28            *b = b'z' - (*b - b'a');
29        }
30    }
31    // Safety: we only modify ASCII alphabetic characters to other ASCII alphabetic characters.
32    // Therefore, any valid UTF-8 sequences are preserved correctly.
33    unsafe { String::from_utf8_unchecked(bytes) }
34}
happy_cracking/crypto/atbash.rs

happy_cracking/crypto/
atbash.rs
