Tweak Input

The tweak input is derived through either of the following methods:

• Extract from input message - If the tweak is set to be derived from input message, then the left and right property settings are used as a configurable tweak option.
• API argument - If the tweak is set to be derived through API argument, then the tweak value is provided as an input parameter through the API during the protect or unprotect operation.

The resultant tweak input is zero for the following conditions:

• When extracting the tweak from input message, the left and right property settings are set to zero.
• When tweak input is to be derived as an API argument, the tweak input parameter is empty or not specified.

The maximum supported tweak input length is 256 bytes.