Module vonuvoli_scheme::externals::blake2

An implementation of the BLAKE2 hash functions.

Based on the blake2-rfc crate.

Usage

Blake2b can be used in the following way:

use blake2::{Blake2b, Digest};

// create a Blake2b object
let mut hasher = Blake2b::new();

// write input message
hasher.input(b"hello world");

// read hash digest and consume hasher
let output = hasher.result();
println!("{:x}", output);

Same example for Blake2s:

use blake2::{Blake2s, Digest};

let mut hasher = Blake2s::new();
hasher.input(b"hello world");
let output = hasher.result();
println!("{:x}", output);

Variable output size

Both Blake2b and Blake2s support variable output sizes through VariableOutput trait. Input trait has to be imported as well.

use blake2::Blake2b;
use blake2::digest::{Input, VariableOutput};

let mut hasher = Blake2b::new(10).unwrap();
// instead of `input` method here we should use `process`
hasher.process(b"my_input");
let mut buf = [0u8; 10];
hasher.variable_result(&mut buf).unwrap();
assert_eq!(buf, [44, 197, 92, 132, 228, 22, 146, 78, 100, 0])

Message Authentication Code (MAC)

BLAKE2 can be used as a MAC without any additionall constructs:

use blake2::Blake2b;
use blake2::crypto_mac::Mac;

let mut hasher = Blake2b::new(b"my key").unwrap();
hasher.input(b"hello world");

// `result` has type `MacResult` which is a thin wrapper around array of
// bytes for providing constant time equality check
let result = hasher.result();
// To get underlying array use `code` method, but be carefull, since
// incorrect use of the code value may permit timing attacks which defeat
// the security provided by the `MacResult`
let code_bytes = result.code();

// To verify the message it's recommended to use `verify` method
let mut hasher = Blake2b::new(b"my key").unwrap();
hasher.input(b"hello world");
// `verify` return `Ok(())` if code is correct, `Err(MacError)` otherwise
hasher.verify(&code_bytes).unwrap();

Modules

crypto_mac	This crate provides trait for Message Authentication Code (MAC) algorithms.
digest	This crate provides traits for describing funcionality of cryptographic hash functions.

Structs

Blake2b	Hash function context.
Blake2s	Hash function context.

Traits

Digest

The Digest trait specifies an interface common for digest functions.