# MLKEM Class

The MLKEM class can be used to establish a shared secret key through Module-Lattice-Based Key-Encapsulation Mechanism (ML-KEM) cryptography.

## Syntax

```text
ipworksencrypt.MLKEM
```

## Remarks

The MLKEM component can be used to establish a shared secret key through Module-Lattice-Based Key-Encapsulation Mechanism (ML-KEM) cryptography. Includes support for ML-KEM-512, ML-KEM-768, and ML-KEM-1024 parameter sets.

Note that by default the component uses ML-KEM-512. You may specify the parameter set by setting [ParamSet](#ParamSet).

## Property List

*The following is the full list of the properties of the class with short descriptions. Click on the links for further details.*

|  |  |
| --- | --- |
| [CipherText](#ciphertext-property-mlkem-class) | The cipher text. |
| [Key](#key-property-mlkem-class) | The ML-KEM key. |
| [SharedSecret](#sharedsecret-property-mlkem-class) | The computed shared secret. |
| [UseHex](#usehex-property-mlkem-class) | Whether binary values are hex encoded. |

## Method List

*The following is the full list of the methods of the class with short descriptions. Click on the links for further details.*

|  |  |
| --- | --- |
| [Config](#config-method-mlkem-class) | Sets or retrieves a configuration setting. |
| [CreateKey](#createkey-method-mlkem-class) | Creates a new key. |
| [Decapsulate](#decapsulate-method-mlkem-class) | Decapsulates a shared secret. |
| [Encapsulate](#encapsulate-method-mlkem-class) | Encapsulates a shared secret. |
| [Reset](#reset-method-mlkem-class) | Resets the class. |

## Event List

*The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.*

|  |  |
| --- | --- |
| [Error](#error-event-mlkem-class) | Fired when information is available about errors during data delivery. |

## Config Settings

*The following is a list of config settings for the class with short descriptions. Click on the links for further details.*

|  |  |
| --- | --- |
| [ParamSet](#ParamSet) | The ML-KEM parameter set. |
| [BuildInfo](#BuildInfo) | Information about the product's build. |
| [GUIAvailable](#GUIAvailable) | Whether or not a message loop is available for processing events. |
| [LicenseInfo](#LicenseInfo) | Information about the current license. |
| [MaskSensitiveData](#MaskSensitiveData) | Whether sensitive data is masked in log messages. |
| [UseDaemonThreads](#UseDaemonThreads) | Whether threads created by the class are daemon threads. |
| [UseFIPSCompliantAPI](#UseFIPSCompliantAPI) | Tells the class whether or not to use FIPS certified APIs. |
| [UseInternalSecurityAPI](#UseInternalSecurityAPI) | Whether or not to use the system security libraries or an internal implementation. |
| [UseVirtualThreads](#UseVirtualThreads) | Whether threads created by the class use virtual threads instead of platform threads. |

# CipherText Property ([MLKEM](#mlkem-class) Class)

The cipher text.

## Syntax

```text
public byte[] getCipherText();
public void setCipherText(byte[] cipherText);
```

## Default Value

""

## Remarks

This property holds the ML-KEM ciphertext.

It is populated by [Encapsulate](#encapsulate-method-mlkem-class) and must be set before calling [Decapsulate](#decapsulate-method-mlkem-class).

# Key Property ([MLKEM](#mlkem-class) Class)

The ML-KEM key.

## Syntax

```text
public MLKEMKey getKey();
public void setKey(MLKEMKey key);
```

## Remarks

This property specifies the ML-KEM public or private key.

The public key is required before calling [Encapsulate](#encapsulate-method-mlkem-class), and the private key is required before calling [Decapsulate](#decapsulate-method-mlkem-class).

ML-KEM keys are made up of raw private key and public key fields.

[PublicKey](#MLKEMKey_f_PublicKey) holds the public key.

[PrivateKey](#MLKEMKey_f_PrivateKey) holds the private key.

 Please refer to the [MLKEMKey](#mlkemkey-type) type for a complete list of fields.

# SharedSecret Property ([MLKEM](#mlkem-class) Class)

The computed shared secret.

## Syntax

```text
public byte[] getSharedSecret();
```

## Default Value

""

## Remarks

This property holds the shared secret computed by [Encapsulate](#encapsulate-method-mlkem-class) or [Decapsulate](#decapsulate-method-mlkem-class).

This property is read-only.

# UseHex Property ([MLKEM](#mlkem-class) Class)

Whether binary values are hex encoded.

## Syntax

```text
public boolean isUseHex();
public void setUseHex(boolean useHex);
```

## Default Value

False

## Remarks

This property specifies whether [CipherText](#ciphertext-property-mlkem-class) and [SharedSecret](#sharedsecret-property-mlkem-class) are hex encoded when [Encapsulate](#encapsulate-method-mlkem-class) is called.

If set to *False* (default), values are provided as-is with no encoding.

When [Decapsulate](#decapsulate-method-mlkem-class) is called and this property is set to *True*, [CipherText](#ciphertext-property-mlkem-class) is treated as hex encoded and [SharedSecret](#sharedsecret-property-mlkem-class) is hex encoded when populated.

# Config Method ([MLKEM](#mlkem-class) Class)

Sets or retrieves a configuration setting.

## Syntax

```text
public String config(String configurationString);
```

## Remarks

Config is a generic method available in every class. It is used to set and retrieve [configuration settings](#config-settings-mlkem-class) for the class.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these *internal properties* is provided through the Config method.

To set a configuration setting named *PROPERTY*, you must call *Config("PROPERTY=VALUE")*, where *VALUE* is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a [configuration setting](#config-settings-mlkem-class), you must call *Config("PROPERTY")*. The value will be returned as a string.

# CreateKey Method ([MLKEM](#mlkem-class) Class)

Creates a new key.

## Syntax

```text
public void createKey();
```

## Remarks

CreateKey creates a new ML-KEM public and private key pair.

When this method is called, [Key](#key-property-mlkem-class) is populated with the generated raw public and private key values. The parameter set is controlled by the *ParamSet* configuration setting.

# Decapsulate Method ([MLKEM](#mlkem-class) Class)

Decapsulates a shared secret.

## Syntax

```text
public void decapsulate();
```

## Remarks

This method uses the private key in [Key](#key-property-mlkem-class) and the ciphertext in [CipherText](#ciphertext-property-mlkem-class) to recover the shared secret.

The shared secret is available from [SharedSecret](#sharedsecret-property-mlkem-class).

# Encapsulate Method ([MLKEM](#mlkem-class) Class)

Encapsulates a shared secret.

## Syntax

```text
public void encapsulate();
```

## Remarks

This method uses the public key in [Key](#key-property-mlkem-class) to generate a shared secret and ciphertext.

The generated shared secret is available from [SharedSecret](#sharedsecret-property-mlkem-class), and the ciphertext is available from [CipherText](#ciphertext-property-mlkem-class).

# Reset Method ([MLKEM](#mlkem-class) Class)

Resets the class.

## Syntax

```text
public void reset();
```

## Remarks

When called, the class will reset all of its properties to their default values.

# Error Event ([MLKEM](#mlkem-class) Class)

Fired when information is available about errors during data delivery.

## Syntax

```text
public class DefaultMLKEMEventListener implements MLKEMEventListener {
  ...
  public void error(MLKEMErrorEvent e) {}
  ...
}

public class MLKEMErrorEvent {
  public int errorCode;
  public String description;
}
```

## Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the class throws an exception.

The *ErrorCode* parameter contains an error code, and the *Description* parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the [Error Codes](#trappable-errors-mlkem-class) section.

# MLKEMKey Type

Contains a raw ML-KEM key.

## Remarks

This type contains the raw public and private key values used by the MLKEM component.

The following fields are available:

- [PrivateKey](#MLKEMKey_f_PrivateKey)

- [PublicKey](#MLKEMKey_f_PublicKey)

## Fields

 **PrivateKey** *String*
*Default Value: ""*

The raw ML-KEM private key.

 **PrivateKeyB** *byte[]*
*Default Value: ""*

The raw ML-KEM private key.

 **PublicKey** *String*
*Default Value: ""*

The raw ML-KEM public key.

 **PublicKeyB** *byte[]*
*Default Value: ""*

The raw ML-KEM public key.

## Constructors

```text
public MLKEMKey();
```

 The default constructor creates a new MLKEMKey instance but does not assign a public or private key.

```text
public MLKEMKey(byte[] publicKey);
```

 The public key constructor assigns an existing public key.

```text
public MLKEMKey(byte[] publicKey, byte[] privateKey);
```

 The private key constructor assigns an existing private key.

# Config Settings ([MLKEM](#mlkem-class) Class)

 The class accepts one or more of the following *configuration settings*. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these *internal properties* is provided through the [Config](#config-method-mlkem-class) method.

### MLKEM Config Settings

**ParamSet**: The ML-KEM parameter set.This setting specifies the ML-KEM parameter set to use when creating keys, encapsulating, and decapsulating. Possible values are:

- 512 (default)
- 768
- 1024

### Base Config Settings

**BuildInfo**: Information about the product's build.When queried, this setting will return a string containing information about the product's build.

**GUIAvailable**: Whether or not a message loop is available for processing events.In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The class will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation.

In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting [GUIAvailable](#GUIAvailable) to *false* will ensure that the class does not attempt to process external events.

**LicenseInfo**: Information about the current license.When queried, this setting will return a string containing information about the license this instance of a class is using. It will return the following information:

- Product: The product the license is for.
- Product Key: The key the license was generated from.
- License Source: Where the license was found (e.g., RuntimeLicense, License File).
- License Type: The type of license installed (e.g., Royalty Free, Single Server).
- Last Valid Build: The last valid build number for which the license will work.

**MaskSensitiveData**: Whether sensitive data is masked in log messages.In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to *true* to mask sensitive data. The default is *true*.

**UseDaemonThreads**: Whether threads created by the class are daemon threads.If set to True (default), when the class creates a thread, the thread's Daemon property will be explicitly set to True. When set to False, the class will not set the Daemon property on the created thread. The default value is True.

**UseFIPSCompliantAPI**: Tells the class whether or not to use FIPS certified APIs.When set to *true*, the class will utilize the underlying operating system's certified APIs. Java editions, regardless of OS, utilize Bouncy Castle Federal Information Processing Standards (FIPS), while all other Windows editions make use of Microsoft security libraries.

The Java edition requires installation of the FIPS-certified Bouncy Castle library regardless of the target operating system. This can be downloaded from [https://www.bouncycastle.org/fips-java/](https://www.bouncycastle.org/fips-java/). Only the "Provider" library is needed. The jar file should then be installed in a JRE search path.

The following classes must be imported in the application in which the component will be used:

```text
import java.security.Security;
import org.bouncycastle.jcajce.provider.BouncyCastleFipsProvider;
```

The Bouncy Castle provider must be added as a valid provider and must also be configured to operate in FIPS mode:

```text
System.setProperty("org.bouncycastle.fips.approved_only","true");
Security.addProvider(new BouncyCastleFipsProvider());
```

When [UseFIPSCompliantAPI](#UseFIPSCompliantAPI) is *true*, Secure Sockets Layer (SSL)-enabled classes can optionally be configured to use the Transport Layer Security (TLS) Bouncy Castle library. When SSLProvider is set to *sslpAutomatic* (default) or *sslpInternal*, an internal TLS implementation is used, but all cryptographic operations are offloaded to the Bouncy Castle FIPS provider to achieve FIPS-compliant operation. If SSLProvider is set to *sslpPlatform*, the Bouncy Castle JSSE will be used in place of the internal TLS implementation.

To enable the use of the Bouncy Castle JSSE take the following steps in addition to the steps above. Both the Bouncy Castle FIPS provider and the Bouncy Castle JSSE must be configured to use the Bouncy Castle TLS library in FIPS mode. Obtain the Bouncy Castle TLS library from [https://www.bouncycastle.org/fips-java/](https://www.bouncycastle.org/fips-java/). The jar file should then be installed in a JRE search path.

The following classes must be imported in the application in which the component will be used:

```text
import java.security.Security;
import org.bouncycastle.jcajce.provider.BouncyCastleFipsProvider;

//required to use BCJSSE when SSLProvider is set to sslpPlatform
import org.bouncycastle.jsse.provider.BouncyCastleJsseProvider;
```

The Bouncy Castle provider must be added as a valid provider and also must be configured to operate in FIPS mode:

```text
System.setProperty("org.bouncycastle.fips.approved_only","true");
Security.addProvider(new BouncyCastleFipsProvider());

//required to use BCJSSE when SSLProvider is set to sslpPlatform
Security.addProvider(new BouncyCastleJsseProvider("fips:BCFIPS"));

//optional - configure logging level of BCJSSE
Logger.getLogger("org.bouncycastle.jsse").setLevel(java.util.logging.Level.OFF);

//configure the class to use BCJSSE
component.setSSLProvider(1); //platform
component.config("UseFIPSCompliantAPI=true");
```

 NOTE: TLS 1.3 support requires the Bouncy Castle TLS library version 1.0.14 or later.

FIPS mode can be enabled by setting the *UseFIPSCompliantAPI* configuration setting to *true*. This is a static setting that applies to all instances of all classes of the toolkit within the process. It is recommended to enable or disable this setting once before the component has been used to establish a connection. Enabling FIPS while an instance of the component is active and connected may result in unexpected behavior.

For more details, please see the [FIPS 140-2 Compliance](https://www.nsoftware.com/kb/articles/fips.rst) article.

NOTE: Enabling FIPS compliance requires a special license; please contact [sales@nsoftware.com](mailto:sales@nsoftware.com) for details.

**UseInternalSecurityAPI**: Whether or not to use the system security libraries or an internal implementation. When set to *false*, the class will use the system security libraries by default to perform cryptographic functions where applicable.

Setting this configuration setting to *true* tells the class to use the internal implementation instead of using the system security libraries.

 This setting is set to *false* by default on all platforms.

**UseVirtualThreads**: Whether threads created by the class use virtual threads instead of platform threads.If set to *true*, when the class creates a thread, it will be created as a virtual thread instead of a platform thread. Virtual threads are lightweight threads managed by the JVM that are multiplexed onto a small pool of carrier threads, significantly reducing memory usage and platform thread count under high-concurrency workloads. Requires Java 24 or later. The default value is *false*.

# Trappable Errors ([MLKEM](#mlkem-class) Class)

### MLKEM Errors

|  |  |
| --- | --- |
| 102 | No Key specified. |
| 120 | Invalid parameter set. |