- All Implemented Interfaces:
DerivationFunction, MacDerivationFunction
public class KDFCounterBytesGenerator
extends java.lang.Object
implements MacDerivationFunction
This KDF has been defined by the publicly available NIST SP 800-108 specification.
NIST SP800-108 allows for alternative orderings of the input fields, meaning that the input can be formated in multiple ways.
There are 3 supported formats: - Below [i]_2 is a counter of r-bits length concatenated to the fixedInputData.
1: K(i) := PRF( KI, [i]_2 || Label || 0x00 || Context || [L]_2 ) with the counter at the very beginning of the fixedInputData (The default implementation has this format)
2: K(i) := PRF( KI, Label || 0x00 || Context || [L]_2 || [i]_2 ) with the counter at the very end of the fixedInputData
3a: K(i) := PRF( KI, Label || 0x00 || [i]_2 || Context || [L]_2 ) OR:
3b: K(i) := PRF( KI, Label || 0x00 || [i]_2 || [L]_2 || Context ) OR:
3c: K(i) := PRF( KI, Label || [i]_2 || 0x00 || Context || [L]_2 ) etc[] with the counter somewhere in the 'middle' of the fixedInputData.
This function must be called with the following KDFCounterParameters():
KI
The part of the fixedInputData that comes BEFORE the counter OR null
the part of the fixedInputData that comes AFTER the counter OR null
the length of the counter in bits (not bytes)
Resulting function calls assuming an 8 bit counter.
1. KDFCounterParameters(ki, null, "Label || 0x00 || Context || [L]_2]", 8);
2. KDFCounterParameters(ki, "Label || 0x00 || Context || [L]_2]", null, 8);
3a. KDFCounterParameters(ki, "Label || 0x00", "Context || [L]_2]", 8);
3b. KDFCounterParameters(ki, "Label || 0x00", "[L]_2] || Context", 8);
3c. KDFCounterParameters(ki, "Label", "0x00 || Context || [L]_2]", 8);