Struct casper_hashing::Digest

pub struct Digest(_);

The output of the hash function.

Implementations

impl Digest

pub const LENGTH: usize = 32usize

The number of bytes in a Digest.

pub const SENTINEL_NONE: Digest = _

Sentinel hash to be used for hashing options in the case of None.

pub const SENTINEL_RFOLD: Digest = _

Sentinel hash to be used by hash_slice_rfold. Terminates the fold.

pub const SENTINEL_MERKLE_TREE: Digest = _

Sentinel hash to be used by hash_vec_merkle_tree in the case of an empty list.

pub fn hash<T: AsRef<[u8]>>(data: T) -> Digest

Creates a 32-byte BLAKE2b hash digest from a given a piece of data

pub fn hash_pair<T: AsRef<[u8]>, U: AsRef<[u8]>>(data1: T, data2: U) -> Digest

Hashes a pair of byte slices.

pub fn value(&self) -> [u8; 32]

Returns the underlying BLAKE2b hash bytes

pub fn into_vec(self) -> Vec<u8>

Converts the underlying BLAKE2b hash digest array to a Vec

pub fn hash_vec_merkle_tree(vec: Vec<Digest>) -> Digest

Hashes a Vec of Digests into a single Digest by constructing a Merkle tree. Reduces pairs of elements in the Vec by repeatedly calling Digest::hash_pair. This hash procedure is suited to hashing BTrees.

The pattern of hashing is as follows. It is akin to graph reduction:

a b c d e f
|/  |/  |/
g   h   i
| /   /
|/   /
j   k
| /
|/
l

Returns Digest::SENTINEL_MERKLE_TREE when the input is empty.

pub fn hash_btree_map<K, V>(btree_map: &BTreeMap<K, V>) -> Result<Digest, Error>where K: ToBytes, V: ToBytes,

Hashes a BTreeMap.

pub fn hash_slice_rfold(slice: &[Digest]) -> Digest

Hashes a &[Digest] using a right fold.

This pattern of hashing is as follows:

hash_pair(a, &hash_pair(b, &hash_pair(c, &SENTINEL_RFOLD)))

Unlike Merkle trees, this is suited to hashing heterogeneous lists we may wish to extend in the future (ie, hashes of data structures that may undergo revision).

Returns Digest::SENTINEL_RFOLD when given an empty slice as input.

pub fn hash_slice_with_proof(slice: &[Digest], proof: Digest) -> Digest

Hashes a &[Digest] using a right fold. Uses proof as a Merkle proof for the missing tail of the slice.

pub fn from_hex<T: AsRef<[u8]>>(hex_input: T) -> Result<Self, Error>

Returns a Digest parsed from a hex-encoded Digest.

Trait Implementations

impl AsRef<[u8]> for Digest

fn as_ref(&self) -> &[u8]

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for Digest

fn clone(&self) -> Digest

Returns a copy of the value.

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

Performs copy-assignment from source.

impl DataSize for Digest

const IS_DYNAMIC: bool = false

If true, the type has a heap size that can vary at runtime, depending on the actual value.

const STATIC_HEAP_SIZE: usize = 0usize

The amount of space a value of the type always occupies. If IS_DYNAMIC is false, this is the total amount of heap memory occupied by the value. Otherwise this is a lower bound.

fn estimate_heap_size(&self) -> usize

Estimates the size of heap memory taken up by this value.

impl Debug for Digest

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Digest

fn default() -> Digest

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Digest

fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error>

Deserialize this value from the given Serde deserializer.

impl Display for Digest

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<[u8; 32]> for Digest

fn from(arr: [u8; 32]) -> Self

Converts to this type from the input type.

impl From<Digest> for [u8; 32]

fn from(hash: Digest) -> Self

Converts to this type from the input type.

impl FromBytes for Digest

fn from_bytes(bytes: &[u8]) -> Result<(Self, &[u8]), Error>

Deserializes the slice into Self.

fn from_vec(bytes: Vec<u8, Global>) -> Result<(Self, Vec<u8, Global>), Error>

Deserializes the Vec<u8> into Self.

impl Hash for Digest

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl JsonSchema for Digest

fn schema_name() -> String

The name of the generated JSON Schema.

fn json_schema(gen: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn is_referenceable() -> bool

Whether JSON Schemas generated for this type should be re-used where possible using the $ref keyword.

impl LowerHex for Digest

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Ord for Digest

fn cmp(&self, other: &Digest) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Selfwhere Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Selfwhere Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl PartialEq<Digest> for Digest

fn eq(&self, other: &Digest) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd<Digest> for Digest

fn partial_cmp(&self, other: &Digest) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Digest

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.

impl ToBytes for Digest

fn to_bytes(&self) -> Result<Vec<u8>, Error>

Serializes &self to a Vec<u8>.

fn serialized_length(&self) -> usize

Returns the length of the Vec<u8> which would be returned from a successful call to to_bytes() or into_bytes(). The data is not actually serialized, so this call is relatively cheap.

fn into_bytes(self) -> Result<Vec<u8, Global>, Error>where Self: Sized,

Consumes self and serializes to a Vec<u8>.

impl<'a> TryFrom<&'a [u8]> for Digest

type Error = TryFromSliceError

The type returned in the event of a conversion error.

fn try_from(slice: &[u8]) -> Result<Digest, Self::Error>

Performs the conversion.

impl UpperHex for Digest

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Copy for Digest

impl Eq for Digest

impl StructuralEq for Digest

impl StructuralPartialEq for Digest