extendhash

extendhash is a Rust library to compute hash extensions. Currently only MD5 is supported, but more hash algorithms are planned in the future.

Usage

use extendhash::MD5;

let secret_data = "This is a secret!".as_bytes();
let hash = MD5::compute_hash(secret_data);
let secret_data_length = secret_data.len();

// Now we try computing a hash extension,
// assuming that `secret_data` is not available.
// We only need `hash` and `secret_data_length`.
let appended_message = "Appended message.".as_bytes();
let combined_hash = MD5::extend_hash(
	hash, secret_data_length, appended_message);

// Now we verify that `combined_hash` matches
// the concatenation (note the intermediate
// padding):
let mut combined_data = Vec::<u8>::new();
combined_data.extend_from_slice(secret_data);
let intermediate_padding = MD5::padding_for_length(secret_data_length);
combined_data.extend_from_slice(intermediate_padding.as_slice());
combined_data.extend_from_slice(appended_message);
assert_eq!(combined_hash, MD5::compute_hash(combined_data.as_slice()));

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

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.