Crate hashes

Rust hashes library.

This is a simple, no-dependency library which implements the hash functions needed by Bitcoin. These are SHA256, SHA256d, and RIPEMD160. As an ancillary thing, it exposes hexadecimal serialization and deserialization, since these are needed to display hashes anway.

Commonly used operations

Hashing a single byte slice or a string:

use bitcoin_hashes::sha256;
use bitcoin_hashes::Hash;

let bytes = [0u8; 5];
let hash_of_bytes = sha256::Hash::hash(&bytes);
let hash_of_string = sha256::Hash::hash("some string".as_bytes());

Hashing content from a reader:

use bitcoin_hashes::sha256;
use bitcoin_hashes::Hash;

#[cfg(std)]
let mut reader: &[u8] = b"hello"; // in real code, this could be a `File` or `TcpStream`
let mut engine = sha256::HashEngine::default();
std::io::copy(&mut reader, &mut engine)?;
let hash = sha256::Hash::from_engine(engine);

#[cfg(not(std))]

Hashing content by std::io::Write on HashEngine:

use bitcoin_hashes::sha256;
use bitcoin_hashes::Hash;
use std::io::Write;

#[cfg(std)]
let mut part1: &[u8] = b"hello";
let mut part2: &[u8] = b" ";
let mut part3: &[u8] = b"world";
let mut engine = sha256::HashEngine::default();
engine.write_all(part1)?;
engine.write_all(part2)?;
engine.write_all(part3)?;
let hash = sha256::Hash::from_engine(engine);

#[cfg(not(std))]

Modules

• cmp
  Useful comparison functions.
• hash160
  HASH160 (SHA256 then RIPEMD160) implementation.
• hex
  Hex encoding and decoding.
• hmac
  Hash-based Message Authentication Code (HMAC).
• ripemd160
  RIPEMD160 implementation.
• serde
  Serde
• serde_macros
  Macros for serde trait implementations, and supporting code.
• sha1
  SHA1 implementation.
• sha256
  SHA256 implementation.
• sha384
  SHA384 implementation.
• sha512
  SHA512 implementation.
• sha256d
  SHA256d implementation (double SHA256).
• sha256t
  SHA256t implementation (tagged SHA256).
• sha512_256
  SHA512_256 implementation.
• siphash24
  SipHash 2-4 implementation.

Macros

• borrow_slice_impl
  Adds slicing traits implementations to a given type $ty
• hash_newtype
  Creates a new newtype around a Hash type.
• hex_fmt_impl
  Adds hexadecimal formatting implementation of a trait $imp to a given type $ty.
• serde_impl
  Implements Serialize and Deserialize for a type $t which represents a newtype over a byte-slice over length $len.
• sha256t_hash_newtype
  Macro used to define a newtype tagged hash.

Structs

• FromSliceError
  Attempted to create a hash from an invalid length slice.
• Hmac
  A hash computed from a RFC 2104 HMAC. Parameterized by the underlying hash function.
• HmacEngine
  Pair of underlying hash engines, used for the inner and outer hash of HMAC.

Traits

• Hash
  Trait which applies to hashes of all types.
• HashEngine
  A hashing engine which bytes can be serialized into.