ChaChaEngine.Permute Method

public static void Permute(
	Span<uint> state,
	int rounds
)

Public Shared Sub Permute ( 
	state As Span(Of UInteger),
	rounds As Integer
)

public:
static void Permute(
	Span<unsigned int> state, 
	int rounds
)

static member Permute : 
        state : Span<uint32> * 
        rounds : int -> unit 

Parameters

state  Span<UInt32>

The 16-word state to permute. Must have exactly 16 elements.

rounds  Int32

The number of rounds to apply (must be 8, 12, or 20).

This method performs the ChaCha permutation in-place on the provided state. The state is modified directly and represents the output after the specified number of rounds.

Note: This method performs only the permutation step. To generate the final ChaCha output block, the original state must be added to the permuted state (ARX construction).

Reference