Camellia Class
Definition
- Namespace
- Bodu.Security.Cryptography
- Assembly
- Bodu.Security.Cryptography.dll
- Package
- Bodu.Security.Cryptography 1.2.0
- Source
- Camellia.cs
Provides a managed implementation of the Camellia symmetric block cipher, exposing the CamelliaBlockCipher engine through the standard SymmetricAlgorithm framework. This class cannot be inherited.
public sealed class Camellia : ExtendedSymmetricAlgorithm, IDisposable- Inheritance
-
Camellia
- Implements
- Inherited Members
- Extension Methods
Examples
using System.Security.Cryptography;
using Bodu.Security.Cryptography;
using Bodu.Security.Cryptography.Extensions;
using var camellia = new Camellia();
camellia.GenerateKey(); // 256-bit by default
camellia.GenerateIV();
byte[] ciphertext = camellia.Encrypt(plaintext);
byte[] roundTrip = camellia.Decrypt(ciphertext);Remarks
Camellia is a symmetric-key block cipher jointly developed by NTT and Mitsubishi Electric and specified by RFC 3713. It operates on a fixed 128-bit block size and accepts 128-bit, 192-bit, and 256-bit keys. The 128-bit key variant applies 18 Feistel rounds; the 192-bit and 256-bit key variants apply 24 rounds. Camellia has been evaluated and approved by ISO/IEC, CRYPTREC, and NESSIE.
This class integrates with the .NET SymmetricAlgorithm framework and supports standard block cipher modes via the BlockMode property. The default mode is CBC with PKCS7 padding and a default key size of 256 bits.
Parameters at a glance.
- Block size: 128 bits (16 bytes).
- Key sizes: 128 (18 rounds), 192 or 256 bits (24 rounds).
- Specification: RFC 3713; approved by ISO/IEC, CRYPTREC, and NESSIE.
- Default mode: CBC; default padding: PKCS7.
When to choose Camellia. Pick Camellia when standards-body approval matters - Japanese CRYPTREC, European NESSIE, and ISO/IEC all list Camellia. It is the standard alternative to AES in many non-US jurisdictions and TLS implementations. Performance characteristics are comparable to AES in software; for new general-purpose work without a procurement constraint Aes is the more widely accelerated default.
The underlying block-cipher implementation is constant-time in its control flow, but the fixed S-box lookup tables are read at data-dependent indices. As such, it is not hardened against timing or cache-based side-channel attacks.
Constructors
Camellia()
Initializes a new instance of the Camellia class with a 256-bit default key size, CBC cipher mode, and PKCS7 padding.
public Camellia()Remarks
Call GenerateKey() and GenerateIV() to produce random key material, or assign Key and IV directly before calling CreateEncryptor(byte[], byte[]?) or CreateDecryptor(byte[], byte[]?).
The key size can be changed via KeySize to 128, 192, or 256 bits prior to generating or assigning a key.
Methods
Create()
Creates a new Camellia instance with default parameters.
public static Camellia Create()Returns
CreateDecryptor(byte[], byte[]?)
Creates a symmetric Camellia decryptor using the specified key and initialization vector.
public override ICryptoTransform CreateDecryptor(byte[] rgbKey, byte[]? rgbIV)Parameters
rgbKeybyte[]The secret key for the symmetric algorithm. Must be exactly 16, 24, or 32 bytes (128, 192, or 256 bits) in length. Must not be null.
rgbIVbyte[]The initialization vector. Must be exactly 16 bytes (128 bits) in length. Must not be null.
Returns
- ICryptoTransform
A symmetric Camellia decryptor object implementing ICryptoTransform.
Exceptions
- ObjectDisposedException
The current instance has been disposed.
- ArgumentNullException
rgbKeyorrgbIVis null.- CryptographicException
rgbKeyis not 16, 24, or 32 bytes in length, orrgbIVis not exactly 16 bytes in length.
CreateEncryptor(byte[], byte[]?)
Creates a symmetric Camellia encryptor using the specified key and initialization vector.
public override ICryptoTransform CreateEncryptor(byte[] rgbKey, byte[]? rgbIV)Parameters
rgbKeybyte[]The secret key for the symmetric algorithm. Must be exactly 16, 24, or 32 bytes (128, 192, or 256 bits) in length. Must not be null.
rgbIVbyte[]The initialization vector. Must be exactly 16 bytes (128 bits) in length. Must not be null.
Returns
- ICryptoTransform
A symmetric Camellia encryptor object implementing ICryptoTransform.
Exceptions
- ObjectDisposedException
The current instance has been disposed.
- ArgumentNullException
rgbKeyorrgbIVis null.- CryptographicException
rgbKeyis not 16, 24, or 32 bytes in length, orrgbIVis not exactly 16 bytes in length.
Dispose(bool)
Releases the unmanaged resources used by the Camellia instance and, optionally, the managed resources.
protected override void Dispose(bool disposing)Parameters
disposingbooltrue to release both managed and unmanaged resources; false to release only unmanaged resources.
Remarks
Clears any cached key material and initialization vector before delegating to the base implementation. This method is idempotent and safe to call multiple times.
GenerateIV()
Generates a cryptographically random initialization vector (IV) suitable for use with the Camellia algorithm.
public override void GenerateIV()Remarks
The generated IV is 16 bytes (128 bits) - matching the Camellia block size - and is assigned directly to IV.
A new IV should be generated for each independent encryption operation when reusing a Camellia instance with the same key.
Exceptions
- ObjectDisposedException
The current instance has been disposed.
GenerateKey()
Generates a cryptographically random key for use with the Camellia algorithm using the currently configured KeySize.
public override void GenerateKey()Remarks
The generated key length is determined by KeySize, which defaults to 256 bits. The generated key is assigned directly to Key.
Exceptions
- ObjectDisposedException
The current instance has been disposed.
Applies to
| Product | Versions |
|---|---|
| .NET | 8, 10 |