org.eclipse.milo.opcua.stack.core.util

Class NonceUtil

java.lang.Object

org.eclipse.milo.opcua.stack.core.util.NonceUtil

public class NonceUtil
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static int	MINIMUM_NONCE_LENGTH The minimum required nonce length for validation by validateNonce(ByteString).

Constructor Summary

Constructors

Constructor and Description
NonceUtil()

Method Summary

Modifier and Type	Method and Description
static void	blockUntilSecureRandomSeeded() Block until the SecureRandom instance has been seeded.
static void	blockUntilSecureRandomSeeded(long timeout, TimeUnit unit) Block for at most timeout waiting for the SecureRandom instance to be seeded.
static void	disableSecureRandom() Disable the use of a SecureRandom for nonce generation.
static void	enableSecureRandom() Enable the use of a SecureRandom for nonce generation.
static ByteString	generateNonce(int length)
static ByteString	generateNonce(SecurityPolicy securityPolicy) Generate a nonce for the given SecurityPolicy.
static boolean	isSecureRandomEnabled()
static boolean	isSecureRandomSeeded()
static CompletionStage<Void>	secureRandomSeeded() Get a CompletionStage that is completed when the SecureRandom instance has been seeded.
static void	validateNonce(ByteString nonce) Validate that nonce is at least MINIMUM_NONCE_LENGTH and is non-zeroes.
static void	validateNonce(ByteString nonce, int minimumLength) Validate that nonce is at least minimumLength and is non-zeroes.
static void	validateNonce(ByteString nonce, SecurityPolicy securityPolicy) Validate that nonce meets the minimum length requirement for securityPolicy and is non-zeroes.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MINIMUM_NONCE_LENGTH

public static final int MINIMUM_NONCE_LENGTH

The minimum required nonce length for validation by validateNonce(ByteString).

This is specified by OPC UA Part 4 to be least 32 bytes in the CreateSession and ActivateSession services.

See Also:

Constant Field Values

Constructor Detail

NonceUtil

public NonceUtil()

Method Detail

blockUntilSecureRandomSeeded

public static void blockUntilSecureRandomSeeded()
                                         throws ExecutionException,
                                                InterruptedException

Block until the SecureRandom instance has been seeded.

Throws:

ExecutionException - if seeding completed exceptionally.

InterruptedException - if the current thread was interrupted.

blockUntilSecureRandomSeeded

public static void blockUntilSecureRandomSeeded(long timeout,
                                                TimeUnit unit)
                                         throws ExecutionException,
                                                InterruptedException,
                                                TimeoutException

Block for at most timeout waiting for the SecureRandom instance to be seeded.

Parameters:

timeout - the maximum time to wait.

unit - the TimeUnit of the timeout argument.

Throws:

ExecutionException - if seeding completed exceptionally.

InterruptedException - if the current thread was interrupted.

TimeoutException - if the wait timed out.

secureRandomSeeded

public static CompletionStage<Void> secureRandomSeeded()

Get a CompletionStage that is completed when the SecureRandom instance has been seeded.

Returns:

a CompletionStage that is completed when the SecureRandom instance has been seeded.

enableSecureRandom

public static void enableSecureRandom()

Enable the use of a SecureRandom for nonce generation. This is the default.

disableSecureRandom

public static void disableSecureRandom()

Disable the use of a SecureRandom for nonce generation. Not recommended.

isSecureRandomEnabled

public static boolean isSecureRandomEnabled()

Returns:

true is nonce generation uses a SecureRandom instance.

isSecureRandomSeeded

public static boolean isSecureRandomSeeded()

Returns:

true if the SecureRandom instance is seeded and available.

generateNonce

public static ByteString generateNonce(int length)

Parameters:

length - the length of the nonce to generate.

Returns:

a nonce of the given length.

generateNonce

public static ByteString generateNonce(SecurityPolicy securityPolicy)

Generate a nonce for the given SecurityPolicy.

The length is determined by the policy: see getNonceLength(SecurityPolicy). Important: this should only be used to generate a nonce exchanged when establishing a secure channel. The nonce used by sessions has different length requirements.

Parameters:

securityPolicy - the SecurityPolicy to use when determining the nonce length.

Returns:

a nonce of the appropriate length for the given security policy.

validateNonce

public static void validateNonce(ByteString nonce,
                                 SecurityPolicy securityPolicy)
                          throws UaException

Validate that nonce meets the minimum length requirement for securityPolicy and is non-zeroes.

Important: this should only be used to validate the nonce exchanged when establishing a secure channel. The nonce used by sessions has different length requirements.

Parameters:

nonce - the nonce to validate.

securityPolicy - the SecurityPolicy dictating the minimum nonce length.

Throws:

UaException - if nonce validation failed.

validateNonce

public static void validateNonce(ByteString nonce)
                          throws UaException

Validate that nonce is at least MINIMUM_NONCE_LENGTH and is non-zeroes.

Parameters:

nonce - the nonce to validate.

Throws:

UaException - if nonce validation failed.

validateNonce

public static void validateNonce(ByteString nonce,
                                 int minimumLength)
                          throws UaException

Validate that nonce is at least minimumLength and is non-zeroes.

Parameters:

nonce - the nonce to validate.

minimumLength - the minimum required nonce length

Throws:

UaException - if nonce validation failed.