Struct GenericHash 

pub struct GenericHash<const KEY_LENGTH: usize, const OUTPUT_LENGTH: usize> { /* private fields */ }

Provides a generic hash function implementation based on Blake2b. Compatible with libsodium’s generic hash.

Like libsodium, OUTPUT_LENGTH may be 1 to 64 bytes and KEY_LENGTH 0 to 64 bytes. CRYPTO_GENERICHASH_BYTES_MIN and CRYPTO_GENERICHASH_KEYBYTES_MIN (16 bytes) are recommended minimums, not enforced ones, and an empty key is the same as no key.

Cloning a hasher copies its in-progress state, so a common prefix can be hashed once and finished with different suffixes. Each copy is wiped when dropped.

Implementations

impl<const KEY_LENGTH: usize, const OUTPUT_LENGTH: usize> GenericHash<KEY_LENGTH, OUTPUT_LENGTH>

pub fn new<Key: ByteArray<KEY_LENGTH>>(key: Option<&Key>) -> Result<Self, Error>

Returns a new incremental hasher with an optional secret key.

Errors

Returns an error if OUTPUT_LENGTH is not 1 to 64 bytes or key is longer than 64 bytes.

pub fn update<Input: Bytes + ?Sized>(&mut self, input: &Input)

Updates the hasher state from input.

pub fn finalize<Output: NewByteArray<OUTPUT_LENGTH>>( self, ) -> Result<Output, Error>

Computes and returns the final hash value.

Errors

Returns an error if the underlying BLAKE2b finalization rejects the output. Initialization normally guarantees a valid output length.

pub fn finalize_to_vec(self) -> Result<Vec<u8>, Error>

Available on crate feature alloc only.

Computes and returns the final hash value as a Vec. Provided for convenience.

Errors

Returns an error if the underlying BLAKE2b finalization rejects the output. Initialization normally guarantees a valid output length.

pub fn hash<Output: NewByteArray<OUTPUT_LENGTH>, Input: Bytes + ?Sized, Key: ByteArray<KEY_LENGTH>>( input: &Input, key: Option<&Key>, ) -> Result<Output, Error>

Computes the hash of input with an optional secret key.

The output length is determined by Output. Providing a key selects keyed BLAKE2b, which can be used as a MAC or PRF.

Errors

Returns an error if OUTPUT_LENGTH is not 1 to 64 bytes or key is longer than 64 bytes.

Example

use base64::Engine as _;
use base64::engine::general_purpose;
use dryoc::generichash::{GenericHash, Hash};

let output: Hash =
    GenericHash::hash(b"hello", Some(b"a very secret key")).expect("hash failed");

assert_eq!(
    general_purpose::STANDARD.encode(&output),
    "AECDe+XJsB6nOkbCsbS/OPXdzpcRm3AolW/Bg1LFY9A="
);

pub fn hash_to_vec<Input: Bytes + ?Sized, Key: ByteArray<KEY_LENGTH>>( input: &Input, key: Option<&Key>, ) -> Result<Vec<u8>, Error>

Available on crate feature alloc only.

Convenience wrapper for GenericHash::hash.

Errors

Returns an error under the same conditions as GenericHash::hash.

Trait Implementations

impl<const KEY_LENGTH: usize, const OUTPUT_LENGTH: usize> Clone for GenericHash<KEY_LENGTH, OUTPUT_LENGTH>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.