Class AsconXof128

Namespace

CryptoHives.Foundation.Security.Cryptography.Hash

Assembly

CryptoHives.Foundation.Security.Cryptography.dll

Computes the Ascon-XOF128 (Extendable Output Function) for the input data.

public sealed class AsconXof128 : AsconHashAlgorithm, ICryptoTransform, IDisposable, IResettable, IExtendableOutput

Inheritance

object

HashAlgorithm

HashAlgorithm

AsconHashAlgorithm

AsconXof128

Implements

ICryptoTransform

IDisposable

IResettable

IExtendableOutput

Inherited Members

AsconHashAlgorithm.RateBytes

AsconHashAlgorithm.BlockSize

AsconHashAlgorithm.Initialize()

AsconHashAlgorithm.P12()

HashAlgorithm.Create(string, bool)

HashAlgorithm.Create(string)

HashAlgorithm.TryComputeHash(ReadOnlySpan<byte>, Span<byte>, out int)

HashAlgorithm.AppendData(ReadOnlySpan<byte>)

HashAlgorithm.AppendData(in ReadOnlySequence<byte>)

HashAlgorithm.TryGetHashAndReset(Span<byte>, out int)

HashAlgorithm.TryReset()

HashAlgorithm.ComputeHash(Stream)

HashAlgorithm.ComputeHash(byte[])

HashAlgorithm.ComputeHash(byte[], int, int)

HashAlgorithm.TransformBlock(byte[], int, int, byte[], int)

HashAlgorithm.TransformFinalBlock(byte[], int, int)

HashAlgorithm.Dispose()

HashAlgorithm.Clear()

HashAlgorithm.HashSize

HashAlgorithm.Hash

HashAlgorithm.InputBlockSize

HashAlgorithm.OutputBlockSize

HashAlgorithm.CanTransformMultipleBlocks

HashAlgorithm.CanReuseTransform

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

object.GetType()

Remarks

This is a fully managed implementation of Ascon-XOF128 that does not rely on OS or hardware cryptographic APIs, ensuring deterministic behavior across all platforms and runtimes.

Ascon-XOF128 is defined in NIST SP 800-232. It is based on the Ascon permutation with 12 rounds and produces variable-length output.

Ascon was the winner of the NIST Lightweight Cryptography competition (2023).

References:

• NIST SP 800-232
• Reference Implementation
• Ascon Homepage

Constructors

AsconXof128()

Initializes a new instance of the AsconXof128 class with default output size.

public AsconXof128()

AsconXof128(int)

Initializes a new instance of the AsconXof128 class with the specified output size.

public AsconXof128(int outputSizeBytes)

Parameters

outputSizeBytes int

The desired output size in bytes.

Exceptions

ArgumentOutOfRangeException

Thrown when outputSizeBytes is less than 1.

Fields

DefaultOutputSizeBits

The default output size in bits.

public const int DefaultOutputSizeBits = 256

Field Value

int

DefaultOutputSizeBytes

The default output size in bytes.

public const int DefaultOutputSizeBytes = 32

Field Value

int

Properties

AlgorithmName

Gets the name of the hash algorithm.

public override string AlgorithmName { get; }

Property Value

string

InitializationVector

Gets the initialization vector values for this variant.

protected override (ulong IV0, ulong IV1, ulong IV2, ulong IV3, ulong IV4) InitializationVector { get; }

Property Value

(ulong IV0, ulong IV1, ulong IV2, ulong IV3, ulong IV4)

OutputSizeBytes

Gets the output size in bytes for this variant.

protected override int OutputSizeBytes { get; }

Property Value

int

Methods

Absorb(ReadOnlySpan<byte>)

Absorbs input data into the XOF state.

public void Absorb(ReadOnlySpan<byte> input)

Parameters

input ReadOnlySpan<byte>

The input data to absorb.

Exceptions

InvalidOperationException

Thrown when data is added after output has been squeezed.

Create()

Creates a new instance of the AsconXof128 class with default output size.

public static AsconXof128 Create()

Returns

AsconXof128

A new Ascon-XOF128 algorithm instance.

Create(int)

Creates a new instance of the AsconXof128 class with the specified output size.

public static AsconXof128 Create(int outputSizeBytes)

Parameters

outputSizeBytes int

The desired output size in bytes.

Returns

AsconXof128

A new Ascon-XOF128 algorithm instance.

HashData(ReadOnlySpan<byte>)

Computes the Ascon-XOF128 hash of source using the default output size and returns it as a new byte array.

public static byte[] HashData(ReadOnlySpan<byte> source)

Parameters

source ReadOnlySpan<byte>

The input data to hash.

Returns

byte[]

A new byte array containing the Ascon-XOF128 hash.

Reset()

Resets the XOF state so the instance can be reused for a new computation.

public void Reset()

Remarks

After calling this method, the instance is in the same state as a newly constructed one. All previously absorbed data and squeezed output are discarded.

Squeeze(Span<byte>)

Squeezes output bytes from the Ascon-XOF128 state.

public void Squeeze(Span<byte> output)

Parameters

output Span<byte>

The buffer to receive the output bytes.

Remarks

After the first call, the hash is finalized and no more data can be absorbed. May be called multiple times for streaming output.

SqueezeOutput(Span<byte>)

Squeezes the output from the internal state.

protected override void SqueezeOutput(Span<byte> destination)

Parameters

destination Span<byte>

The destination span for the output.

TryHashData(ReadOnlySpan<byte>, Span<byte>, out int)

Computes the Ascon-XOF128 hash of source using the default output size and writes it into destination.

public static bool TryHashData(ReadOnlySpan<byte> source, Span<byte> destination, out int bytesWritten)

Parameters

source ReadOnlySpan<byte>

The input data to hash.

destination Span<byte>

The buffer to receive the hash value. Must be at least 32 bytes.

bytesWritten int

When this method returns, the number of bytes written into destination.

Returns

bool

true if destination was large enough; otherwise, false.