Crate iroh_blake3
source ·Expand description
The official Rust implementation of the BLAKE3 cryptographic hash function.
§Examples
// Hash an input all at once.
let hash1 = iroh_blake3::hash(b"foobarbaz");
// Hash an input incrementally.
let mut hasher = iroh_blake3::Hasher::new();
hasher.update(b"foo");
hasher.update(b"bar");
hasher.update(b"baz");
let hash2 = hasher.finalize();
assert_eq!(hash1, hash2);
// Extended output. OutputReader also implements Read and Seek.
let mut output = [0; 1000];
let mut output_reader = hasher.finalize_xof();
output_reader.fill(&mut output);
assert_eq!(hash1, output[..32]);
// Print a hash as hex.
println!("{}", hash1);
§Cargo Features
The std
feature (the only feature enabled by default) is required for
implementations of the Write
and Seek
traits, and also for runtime
CPU feature detection on x86. If this feature is disabled, the only way to
use the x86 SIMD implementations is to enable the corresponding instruction
sets globally, with e.g. RUSTFLAGS="-C target-cpu=native"
. The resulting
binary will not be portable to other machines.
The rayon
feature (disabled by default, but enabled for docs.rs) adds
the Hasher::update_rayon
method, for multithreaded hashing. However,
even if this feature is enabled, all other APIs remain single-threaded.
The NEON implementation is enabled by default for AArch64 but requires the
neon
feature for other ARM targets. Not all ARMv7 CPUs support NEON, and
enabling this feature will produce a binary that’s not portable to CPUs
without NEON support.
The traits-preview
feature enables implementations of traits from the
RustCrypto digest
crate, and re-exports that crate as
traits::digest
. However, the traits aren’t stable, and they’re expected to
change in incompatible ways before that crate reaches 1.0. For that reason,
this crate makes no SemVer guarantees for this feature, and callers who use
it should expect breaking changes between patch versions. (The “-preview”
feature name follows the conventions of the RustCrypto signature
crate.)
Structs§
- An output of the default size, 32 bytes, which provides constant-time equality checking.
- An incremental hash state that can accept any number of writes.
- The error type for
Hash::from_hex
. - An incremental reader for extended output, returned by
Hasher::finalize_xof
.
Constants§
- The number of bytes in a key, 32.
- The number of bytes in a
Hash
, 32.
Functions§
- The key derivation function.
- The default hash function.
- The keyed hash function.