Struct Hash 

pub struct Hash { /* private fields */ }

Implementations

impl Hash

pub fn compact(&self) -> &[u8]

impl Hash

pub const fn data_max_len(&self) -> PackedInt

Returns the length of the hashed data.

The length is stored as a PackedInt, which rounds up, so this is an upper bound for data longer than PackedInt can represent exactly.

impl Hash

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

impl Hash

pub fn from_parts( digest: &[u8; 32], data_len: PackedInt, ) -> Result<Hash, HashError>

Reconstructs a hash from its stored parts: the digest and the packed data length.

The parity block is a deterministic function of the parts, so storage that holds many hashes may keep only the digest and length field and rebuild the full hash on demand.

Errors

• HashError::ZeroDigest if digest is all zeros. No hashed input produces the zero digest, and Hash::validate rejects it, so a hash built from it could never be validated.
• HashError::RSGenerateParityError if parity generation fails.

impl Hash

pub fn hash(data: impl AsRef<[u8]>) -> Result<Hash, HashError>

impl Hash

pub fn parity(&self) -> &[u8; 14]

impl Hash

pub fn to_string(&self) -> String

Returns the canonical Crockford Base32 representation.

pub fn to_crockford(&self) -> String

Returns the Crockford Base32 representation.

The alphabet is case-insensitive on input and excludes the ambiguous glyphs I, L, O, and U, which makes it the better choice for hashes that are read, spoken, or typed by hand.

pub fn to_base64(&self) -> String

Returns the unpadded base64url representation.

This is the shorter of the two representations, and the better choice where a hash is only ever handled by machines.

impl Hash

pub fn validate(bytes: impl AsRef<[u8]>) -> Result<Hash, HashValidationError>

Validates and, where necessary, repairs a hash in any of its representations.

The representation is selected by input length, since the three accepted ranges are disjoint:

length	representation
41..=48	binary, including compact
55..=64	base64url
66..=77	Crockford Base32

Inputs shorter than the full size are treated as truncated and are restored by the Reed-Solomon codec, which corrects up to PARITY byte errors.

Errors

• HashValidationError::InvalidLength if the length matches no representation.
• HashValidationError::RSDecodeError if the damage exceeds what the Reed-Solomon codec can correct.
• HashValidationError::ZeroDigest if the corrected digest is all zeros. No hashed input produces the zero digest, but the all-zero buffer is a valid Reed-Solomon codeword, so it must be rejected explicitly.

impl Hash

pub fn validate_bin_vec(hash: &mut Vec<u8>) -> Result<Hash, HashValidationError>

Trait Implementations

impl Clone for Hash

fn clone(&self) -> Hash

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Hash

impl Debug for Hash

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

Formats the value using the given formatter.

impl Display for Hash

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

Writes the canonical Crockford Base32 representation.

impl Eq for Hash

impl Hash for Hash

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

where H: Hasher,

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 Ord for Hash

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

This method returns an Ordering between self and other.

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

where Self: Sized,

Compares and returns the maximum of two values.

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

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Hash

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

Equality operator ==.

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

Inequality operator !=.

impl PartialOrd for Hash

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

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

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

Tests less than (for self and other) and is used by the < operator.

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

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

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

Tests greater than (for self and other) and is used by the > operator.

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

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

impl TryFrom<&[u8]> for Hash

type Error = HashValidationError

The type returned in the event of a conversion error.

fn try_from(value: &[u8]) -> Result<Hash, <Hash as TryFrom<&[u8]>>::Error>

Performs the conversion.

impl TryFrom<&str> for Hash

type Error = HashValidationError

The type returned in the event of a conversion error.

fn try_from(value: &str) -> Result<Hash, <Hash as TryFrom<&str>>::Error>

Performs the conversion.