Fletcher32 Class

Definition

Namespace

Bodu.IO.Hashing.Checksums

Assembly

Bodu.IO.Hashing.dll

Package

Bodu.IO.Hashing 1.0.0

Source

Fletcher.32.cs

Computes the hash for the input data using the Fletcher-32 hash algorithm. This variant performs a non-cryptographic checksum calculation using two 16-bit accumulators to efficiently detect errors in byte sequences. This class cannot be inherited.

public sealed class Fletcher32 : Fletcher, IResumableHashAlgorithm

Inheritance

object

NonCryptographicHashAlgorithm

BlockNonCryptographicHashAlgorithm

Fletcher

Fletcher32

Implements

IResumableHashAlgorithm

Inherited Members

Fletcher.Append(ReadOnlySpan<byte>)

Fletcher.TryComputeHashFrom(ReadOnlySpan<byte>, ReadOnlySpan<byte>, Span<byte>, out int)

Fletcher.AlgorithmName

BlockNonCryptographicHashAlgorithm.Reset()

NonCryptographicHashAlgorithm.Append(byte[])

NonCryptographicHashAlgorithm.Append(Stream)

NonCryptographicHashAlgorithm.AppendAsync(Stream, CancellationToken)

NonCryptographicHashAlgorithm.GetCurrentHash()

NonCryptographicHashAlgorithm.TryGetCurrentHash(Span<byte>, out int)

NonCryptographicHashAlgorithm.GetCurrentHash(Span<byte>)

NonCryptographicHashAlgorithm.GetHashAndReset()

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

NonCryptographicHashAlgorithm.GetHashAndReset(Span<byte>)

NonCryptographicHashAlgorithm.HashLengthInBytes

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Extension Methods

ComparableExtensions.AtLeast<T>(T, T, IComparer<T>)

ComparableExtensions.AtMost<T>(T, T, IComparer<T>)

ComparableExtensions.IsEqualTo<T>(T, T, IComparer<T>)

ComparableExtensions.Max<T>(T, T, IComparer<T>)

ComparableExtensions.Min<T>(T, T, IComparer<T>)

NonCryptographicHashAlgorithmExtensions.AppendData(NonCryptographicHashAlgorithm, Stream, int)

NonCryptographicHashAlgorithmExtensions.AppendData(NonCryptographicHashAlgorithm, ReadOnlySpan<byte>)

NonCryptographicHashAlgorithmExtensions.AppendDataAsync(NonCryptographicHashAlgorithm, Stream, int, CancellationToken)

NonCryptographicHashAlgorithmExtensions.ComputeHash(NonCryptographicHashAlgorithm, byte[])

NonCryptographicHashAlgorithmExtensions.ComputeHash(NonCryptographicHashAlgorithm, byte[], int, int)

NonCryptographicHashAlgorithmExtensions.ComputeHash(NonCryptographicHashAlgorithm, Stream, int)

NonCryptographicHashAlgorithmExtensions.ComputeHash(NonCryptographicHashAlgorithm, ReadOnlySpan<byte>)

NonCryptographicHashAlgorithmExtensions.ComputeHashAsync(NonCryptographicHashAlgorithm, Stream, int, CancellationToken)

NonCryptographicHashAlgorithmExtensions.TryVerifyHash(NonCryptographicHashAlgorithm, byte[], byte[])

NonCryptographicHashAlgorithmExtensions.TryVerifyHash(NonCryptographicHashAlgorithm, byte[], byte[], out bool)

NonCryptographicHashAlgorithmExtensions.TryVerifyHash(NonCryptographicHashAlgorithm, byte[], string)

NonCryptographicHashAlgorithmExtensions.TryVerifyHash(NonCryptographicHashAlgorithm, Stream, byte[])

NonCryptographicHashAlgorithmExtensions.TryVerifyHash(NonCryptographicHashAlgorithm, Stream, string)

NonCryptographicHashAlgorithmExtensions.TryVerifyHash(NonCryptographicHashAlgorithm, ReadOnlyMemory<byte>, byte[])

NonCryptographicHashAlgorithmExtensions.TryVerifyHash(NonCryptographicHashAlgorithm, ReadOnlySpan<byte>, ReadOnlySpan<byte>)

NonCryptographicHashAlgorithmExtensions.TryVerifyHash(NonCryptographicHashAlgorithm, string, Encoding, byte[])

NonCryptographicHashAlgorithmExtensions.TryVerifyHashAsync(NonCryptographicHashAlgorithm, byte[], byte[], CancellationToken)

NonCryptographicHashAlgorithmExtensions.TryVerifyHashAsync(NonCryptographicHashAlgorithm, byte[], string, CancellationToken)

NonCryptographicHashAlgorithmExtensions.TryVerifyHashAsync(NonCryptographicHashAlgorithm, Stream, byte[], CancellationToken)

NonCryptographicHashAlgorithmExtensions.TryVerifyHashAsync(NonCryptographicHashAlgorithm, Stream, ReadOnlyMemory<byte>, CancellationToken)

NonCryptographicHashAlgorithmExtensions.TryVerifyHashAsync(NonCryptographicHashAlgorithm, Stream, string, CancellationToken)

NonCryptographicHashAlgorithmExtensions.TryVerifyHashAsync(NonCryptographicHashAlgorithm, string, Encoding, byte[], CancellationToken)

NonCryptographicHashAlgorithmExtensions.VerifyHash(NonCryptographicHashAlgorithm, byte[], byte[])

NonCryptographicHashAlgorithmExtensions.VerifyHash(NonCryptographicHashAlgorithm, byte[], string)

NonCryptographicHashAlgorithmExtensions.VerifyHash(NonCryptographicHashAlgorithm, Stream, byte[])

NonCryptographicHashAlgorithmExtensions.VerifyHash(NonCryptographicHashAlgorithm, Stream, string)

NonCryptographicHashAlgorithmExtensions.VerifyHash(NonCryptographicHashAlgorithm, ReadOnlyMemory<byte>, byte[])

NonCryptographicHashAlgorithmExtensions.VerifyHash(NonCryptographicHashAlgorithm, ReadOnlySpan<byte>, ReadOnlySpan<byte>)

NonCryptographicHashAlgorithmExtensions.VerifyHash(NonCryptographicHashAlgorithm, string, Encoding, byte[])

NonCryptographicHashAlgorithmExtensions.VerifyHashAsync(NonCryptographicHashAlgorithm, Stream, byte[], CancellationToken)

NonCryptographicHashAlgorithmExtensions.VerifyHashAsync(NonCryptographicHashAlgorithm, Stream, ReadOnlyMemory<byte>, CancellationToken)

NonCryptographicHashAlgorithmExtensions.VerifyHashAsync(NonCryptographicHashAlgorithm, Stream, string, CancellationToken)

Remarks

Fletcher32 is a lightweight checksum algorithm that produces a 32-bit output by iteratively processing input bytes using two 16-bit rolling sums. It was introduced by Brian Kernighan and Dennis Ritchie and is commonly used in networking, file validation, and embedded systems where error detection is required but cryptographic strength is not.

Parameters at a glance.

• Output size: 32 bits (4 bytes).
• Accumulator width: two 16-bit rolling sums (A and B).
• Modulus: 65535.

When to choose Fletcher32. The general-purpose Fletcher variant - TCP/UDP-style packet checks, file integrity in streaming pipelines, and ZFS-class block sums. Faster than CRC at the cost of weaker burst-error coverage; pick Crc with a 32-bit standard such as CRC32_ISOHDLC when error-detection guarantees matter more than throughput.

important

This algorithm is not cryptographically secure and should not be used for password hashing, digital signatures, or integrity validation in security-sensitive applications.

using Bodu.IO.Hashing.Checksums;
using Bodu.IO.Hashing.Extensions;

var f32 = new Fletcher32();
byte[] checksum = f32.ComputeHash(payload);

Constructors

Fletcher32()

Initializes a new instance of the Fletcher32 class with a 32-bit hash size.

public Fletcher32()

Methods

CreateEmpty()

Creates a new, empty instance of the concrete Fletcher variant. Replaces the former new TSelf() CRTP construction as the factory the base Clone() uses to snapshot running state.

protected override Fletcher CreateEmpty()

Returns

Fletcher

A fresh instance of the derived variant with default accumulator state.

Applies to

Product	Versions
.NET	8, 10

See Also

Fletcher

Fletcher16

Fletcher64