Crate salsa20 

RustCrypto: Salsa20 Stream Cipher

Implementation of the Salsa family of stream ciphers, including the XSalsa variants with an extended 192-bit (24-byte) nonce.

⚠️ Security Warning: Hazmat!

This crate does not ensure ciphertexts are authentic (i.e. by using a MAC to verify ciphertext integrity), which can lead to serious vulnerabilities if used incorrectly!

No security audits of this crate have ever been performed, and it has not been thoroughly assessed to ensure its operation is constant-time on common CPU architectures.

USE AT YOUR OWN RISK!

Examples

use salsa20::Salsa20;
use salsa20::cipher::{KeyIvInit, StreamCipher, StreamCipherSeek};
use hex_literal::hex;

let key = [0x42; 32];
let nonce = [0x24; 8];
let plaintext = hex!("000102030405060708090A0B0C0D0E0F");
let ciphertext = hex!("85843cc5d58cce7b5dd3dd04fa005ded");

// Key and IV must be references to the `Array` type.
// Here we use the `Into` trait to convert arrays into it.
let mut cipher = Salsa20::new(&key.into(), &nonce.into());

let mut buffer = plaintext;

// apply keystream (encrypt)
cipher.apply_keystream(&mut buffer);
assert_eq!(buffer, ciphertext);

let ciphertext = buffer;

// Salsa ciphers support seeking
cipher.seek(0u32);

// decrypt ciphertext by applying keystream again
cipher.apply_keystream(&mut buffer);
assert_eq!(buffer, plaintext);

// stream ciphers can be used with streaming messages
cipher.seek(0u32);
for chunk in buffer.chunks_mut(3) {
    cipher.apply_keystream(chunk);
}
assert_eq!(buffer, ciphertext);

License

Licensed under either of:

• Apache License, Version 2.0
• MIT license

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Re-exports

pub use cipher;

Structs

SalsaCore

The Salsa20 core function.

XSalsaCore

The XSalsa core function.

Functions

hsalsa

The HSalsa20 function defined in the paper “Extending the Salsa20 nonce”

Type Aliases

Key

Key type used by all Salsa variants and XSalsa20.

Nonce

Nonce type used by all Salsa variants.

Salsa8

Salsa20/8 stream cipher (reduced-round variant of Salsa20 with 8 rounds, not recommended)

Salsa12

Salsa20/12 stream cipher (reduced-round variant of Salsa20 with 12 rounds, not recommended)

Salsa20

Salsa20/20 stream cipher (20 rounds; recommended)

XNonce

Nonce type used by XSalsa20.

XSalsa8

XSalsa8 stream cipher (reduced-round variant of XSalsa20 with 8 rounds)

XSalsa12

XSalsa12 stream cipher (reduced-round variant of XSalsa20 with 12 rounds)

XSalsa20

XSalsa20 is a Salsa20 variant with an extended 192-bit (24-byte) nonce.