Aes ConfigurationThe component 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 component, access to these internal properties is provided through the Config method.
AES Configuration Settings
|AdditionalAuthData: Additional authentication data (AAD) used in GCM mode.This setting optionally specifies additional authentication data. The data specified must be hex encoded. This is only applicable when CipherMode is set to 6 (cmGCM). This may be set prior to calling Encrypt or Decrypt. Note that AAD data is authenticated but not encrypted, so it is not included in OutputMessage|
|AuthTag: The authentication tag used in GCM mode.This setting is only applicable when CipherMode is set to 6 (cmGCM). This is populated with a hex encoded value after calling Encrypt. It must be specified with a hex encoded value before calling Decrypt.|
The authentication tag length used in GCM mode.This setting is only applicable when CipherMode is set to 6 (cmGCM).
This may be set before calling Encrypt. It may also be set before calling
Decrypt, but is not required. The default value is 128. Valid values are
The block size, in bits, of the cryptographic operation.The block size is a basic data unit in the operation of encrypt or decrypt. Messages longer than the block size are seen as successive blocks. If the message is shorter than the block size, the message will be padded with extra bits to reach the block size according to PaddingMode.
Different symmetric algorithm has different valid block sizes.
The following algorithms have a fixed block size: AES, CAST, DES, IDEA, RC2, TripleDES, Blowfish, and Twofish.
|CloseInputStreamAfterProcessing: Determines whether or not the input stream is closed after processing.Determines whether or not the input stream set by SetInputStream is closed after processing is complete. The default value is True.|
|CloseOutputStreamAfterProcessing: Determines whether or not the output stream is closed after processing.Determines whether or not the output stream set by SetOutputStream is closed after processing is complete. The default value is True.|
|IncludeAuthTag: Whether to append the authentication tag to the cipher text in GCM mode.This setting controls whether AuthTag is appended to the cipher text. This may be useful in cases where the other party knows to look for the authentication tag at the end of the data. The default value is False.|
|IncludeIV: Whether to prepend the IV to the output data and read the IV from the input data.If this config is true, the IV will be automatically prepended to the output data when calling Encrypt. When calling Decrypt and this setting is True, the IV is automatically extracted form the ciphertext. The default value is False.|
The hash algorithm used to derive the Key and IV from the KeyPassword property.This configuration setting specifies which hash algorithm will be used when deriving the Key and IV from KeyPassword.
The default value is "MD5". Possible values are:
When using any HMAC algorithm the PBKDF#2 method from RFC 2898 is used. Any other algorithm uses PBKDF#1 from the same RFC.
|KeyPasswordIterations: The number of iterations performed when using KeyPassword to derive the Key and IV.This configuration setting specifies the number of iterations performed when using KeyPassword to calculate values for Key and IV. When using PBKDF#2 the default number of iterations is 10,000. When using PBKDF#1 the default number is 10.|
|KeyPasswordSalt: The salt value used in conjunction with the KeyPassword to derive the Key and IV.This configuration setting specifies the hex encoded salt value to be used along with the KeyPassword when calculating values for Key and IV.|
The size, in bits, of secret key for the symmetric algorithm.The legal key sizes vary depending on the algorithm. The KeySize and BlockSize
configuration settings may be set to specify the key and block size (in bits).
This setting is only applicable when KeyPassword is specified.
Note that when using the EzCrypt component, KeySize should be set after setting the Algorithm property.
|UsePlatformAES: Whether to use the platform AES implementation.This setting controls whether the component uses it's own AES implementation or the current platform's implementation. Using the platform implementation is only supported on Windows.|
|XTSDataUnitLength: The length of the XTS data unit.When CipherMode is acmXTS, set this to the length of the XTS data unit in bytes. The default value is 512.|
The initial XTS tweak value.Set this to the initial tweak value when CipherMode is acmXTS. This can be set to either a decimal or
hexadecimal number representing the value. The default value is 0. Here are two examples:
aes.Config("XTSInitialTweak=6700"); // Decimal aes.Config("XTSInitialTweak=C1DD77FDGA"); // Hexadecimal
Base Configuration Settings
|BuildInfo: Information about the product's build.When queried, this setting will return a string containing information about the product's build.|
Tells the component 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 component 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 to false will ensure that the component does not attempt to process external events.
Information about the current license.When queried, this setting will return a string containing information about the license this instance of a component is using. It will return the following information:
|UseDaemonThreads: Whether threads created by the component are daemon threads.If set to True (default), when the component creates a thread the thread's Daemon property will be explicitly set to True. When set to False the component will not set the Daemon property on the created thread. The default value is True.|
|UseInternalSecurityAPI: Tells the component whether or not to use the system security libraries or an internal implementation. By default the component will use the system security libraries to perform cryptographic functions. Setting this to True tells the component to use the internal implementation instead of using the system's security API.|