HashFunction Class

Properties   Methods   Events   Config Settings   Errors  

The HashFunction class implements a wide variety of algorithms for message hashing.

Syntax

secureblackbox.HashFunction

Remarks

HashFunction allows you to hash messages using a variety of industry standard hashing algorithms. Algorithms of both Hash and HMAC type are supported.

You can feed your data to HashFunction in one go, or in chunks. Use Hash method to initialize the hash function, pass the buffer, and calculate the hash in one line of code. Alternatively, use Reset, Update, and Finish in sequence to perform each of those steps individually. You can call Update (and its UpdateFile and UpdateStream variants) repeatedly between Reset and Finish, effectively passing the data in a number of portions: // Feeding the data in one go: Hashfunction hf = new Hashfunction(); hf.Algorithm = "SHA256"; byte[] hash = hf.Hash(buffer); // Feeding data chunk by chunk: Hashfunction hf = new Hashfunction(); hf.Algorithm = "SHA256"; hf.Reset(); hf.Update(buffer1); hf.Update(buffer2); hf.Update(buffer3); byte[] hash = hf.Finish();

To use keyed HMAC, you need to provide the secret key first. Use CryptoKeyManager to create and initialize the key object: Cryptokeymanager km = new Cryptokeymanager(); km.ImportBytes(hmacKey, Constants.kffDER, "SHA256", "", "", Constants.ktSecret); Hashfunction hf = new Hashfunction(); hf.Algorithm = "SHA256"; hf.Key = km.Key; byte[] hash = hf.Hash(buffer);

Use OutputEncoding to set the desired encoding method.

Property List

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

Method List

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

Event List

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

Config Settings

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

Algorithm Property (HashFunction Class)

The hash algorithm to use when hashing data.

Syntax

public String getAlgorithm();


public void setAlgorithm(String algorithm);

Default Value

"SHA256"

Remarks

FIPSMode Property (HashFunction Class)

Reserved.

Syntax

public boolean isFIPSMode();


public void setFIPSMode(boolean FIPSMode);

Default Value

False

Remarks

This property is reserved for future use.

InputStream Property (HashFunction Class)

A stream containing the input data.

Syntax

public java.io.InputStream getInputStream();


public void setInputStream(java.io.InputStream inputStream);

Default Value

null

Remarks

Use this property to specify the data to be used by HashStream and UpdateStream methods.

This property is not available at design time.

JsonSettings Property (HashFunction Class)

Provides a container for JSON settings.

Syntax

public JWSettings getJsonSettings();

Remarks

Use this property when using JSON Web Signatures to tune up the JSON parameters.

This property is read-only.

Please refer to the JWSettings type for a complete list of fields.

Key Property (HashFunction Class)

The key to use during the hashing.

Syntax

public CryptoKey getKey();


public void setKey(CryptoKey key);

Remarks

Assign a properly configured cryptographic key object to this property to use it during the hashing operation. This would normally be a HMAC key.

This property is not available at design time.

Please refer to the CryptoKey type for a complete list of fields.

OutputEncoding Property (HashFunction Class)

The encoding to use for the output data.

Syntax

public int getOutputEncoding();


public void setOutputEncoding(int outputEncoding);


Enumerated values:
  public final static int cetDefault = 0;
  public final static int cetBinary = 1;
  public final static int cetBase64 = 2;
  public final static int cetCompact = 3;
  public final static int cetJSON = 4;

Default Value

0

Remarks

Use this property to configure the type of encoding to be used for the output data.

Config Method (HashFunction Class)

Sets or retrieves a configuration setting.

Syntax

public String config(String configurationString);

Remarks

Config is a generic method available in every class. It is used to set and retrieve configuration settings 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, you must call Config("PROPERTY"). The value will be returned as a string.

DoAction Method (HashFunction Class)

Performs an additional action.

Syntax

public String doAction(String actionID, String actionParams);

Remarks

DoAction is a generic method available in every class. It is used to perform an additional action introduced after the product major release. The list of actions is not fixed, and may be flexibly extended over time.

The unique identifier (case insensitive) of the action is provided in the ActionID parameter.

ActionParams contains the value of a single parameter, or a list of multiple parameters for the action in the form of PARAM1=VALUE1;PARAM2=VALUE2;....

Finish Method (HashFunction Class)

Completes the hash and returns the resulting message digest.

Syntax

public byte[] finish();

Remarks

This method finalizes the hashing operation and returns the message digest of the input data. Use it in conjuction with Reset and Update methods to process data in chunks.

Hash Method (HashFunction Class)

Calculates a message digest over a byte array.

Syntax

public byte[] hash(byte[] buffer);

Remarks

This method calculates and returns a message digest over the content of Buffer. This is a quick way to calculate a hash over a byte array in one go.

HashFile Method (HashFunction Class)

Calculates a message digest over data contained in a file.

Syntax

public byte[] hashFile(String sourceFile);

Remarks

This method calculates and returns a message digest over the data contained in file SourceFile. This is a quick way to calculate a hash over a file content in one go.

HashStream Method (HashFunction Class)

Calculates a message digest over data contained in a stream.

Syntax

public byte[] hashStream();

Remarks

This method calculates a message digest over the data contained in InputStream. This is a quick way of calculating a message data over a stream content in one go.

Reset Method (HashFunction Class)

Resets the hash function context.

Syntax

public void reset();

Remarks

Reset resets the context of the hash function, discarding any data passed to it previously.

Use this method to restart the hash calculation process from scratch.

This method does not affect one-go methods like Hash or HashStream; they reset the hash function context automatically.

Update Method (HashFunction Class)

Feeds a chunk of data to the hash function.

Syntax

public void update(byte[] buffer);

Remarks

This method feeds Buffer to the hash function. Call this method repeatedly to pass your data to the hash function chunk by chunk.

Remember to initialize the hash function with an Reset call before starting to feed data with this method. After the whole volume of data has been sent, complete the calculation and obtain the resulting message digest with a Finish call.

UpdateFile Method (HashFunction Class)

Feeds the contents of a file to the hash function.

Syntax

public void updateFile(String sourceFile);

Remarks

Call this method to pass the contents of a file to the hash function. You can call this function repeatedly and mix it with Update to feed the hash function with many separate chunks of data.

Remember to initialize the hash function with an Reset call before starting hashing the data. Once all the data chunks have been submitted, finalize the hash function and obtain the resulting message digest by calling Finish.

UpdateStream Method (HashFunction Class)

Feeds the contents of a stream to the hash function.

Syntax

public void updateStream();

Remarks

Call this method to pass the contents of a stream to the hash function. You can call this function repeatedly and mix it with Update to feed the hash function with many separate chunks of data.

Remember to initialize the hash function with an Reset call before starting hashing the data. Once all the data chunks have been submitted, finalize the hash function and obtain the resulting message digest by calling Finish.

Error Event (HashFunction Class)

Informs about errors during cryptographic operations.

Syntax

public class DefaultHashFunctionEventListener implements HashFunctionEventListener {
  ...
  public void error(HashFunctionErrorEvent e) {}
  ...
}

public class HashFunctionErrorEvent {
  public int errorCode;
  public String description;
}

Remarks

Class fires this event if an error happens during a cryptographic operation.

ErrorCode contains an error code and Description contains a textual description of the error that happened.

Notification Event (HashFunction Class)

This event notifies the application about an underlying control flow event.

Syntax

public class DefaultHashFunctionEventListener implements HashFunctionEventListener {
  ...
  public void notification(HashFunctionNotificationEvent e) {}
  ...
}

public class HashFunctionNotificationEvent {
  public String eventID;
  public String eventParam;
}

Remarks

The class fires this event to let the application know about some event, occurrence, or milestone in the class. For example, it may fire to report completion of the document processing. The list of events being reported is not fixed, and may be flexibly extended over time.

The unique identifier of the event is provided in the EventID parameter. EventParam contains any parameters accompanying the occurrence. Depending on the type of the class, the exact action it is performing, or the document being processed, one or both may be omitted.

CryptoKey Type

This container represents a cryptographic key.

Remarks

This type is a universal placeholder for cryptographic keys.

Fields

Constructors

public CryptoKey();

JWSettings Type

This container represents JSON web security settings.

Remarks

This type contains properties specific to JSON Web Security.

Fields

Constructors

public JWSettings();

Config Settings (HashFunction 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 method.

HashFunction Config Settings

Base Config Settings

Trappable Errors (HashFunction Class)

HashFunction Errors