private static void Block(ChaCha20 chacha20)
{
var temp = chacha20.Copy();
FullRound(temp);
FullRound(temp);
FullRound(temp);
FullRound(temp);
FullRound(temp);
FullRound(temp);
FullRound(temp);
FullRound(temp);
FullRound(temp);
FullRound(temp);
unchecked
{
chacha20.State0 += temp.State0;
chacha20.State1 += temp.State1;
chacha20.State2 += temp.State2;
chacha20.State3 += temp.State3;
chacha20.State4 += temp.State4;
chacha20.State5 += temp.State5;
chacha20.State6 += temp.State6;
chacha20.State7 += temp.State7;
chacha20.State8 += temp.State8;
chacha20.State9 += temp.State9;
chacha20.StateA += temp.StateA;
chacha20.StateB += temp.StateB;
chacha20.StateC += temp.StateC;
chacha20.StateD += temp.StateD;
chacha20.StateE += temp.StateE;
chacha20.StateF += temp.StateF;
}
}
private static void FullRound(ChaCha20 chacha20)
{
QuarterRound(ref chacha20.State0, ref chacha20.State4, ref chacha20.State8, ref chacha20.StateC);
QuarterRound(ref chacha20.State1, ref chacha20.State5, ref chacha20.State9, ref chacha20.StateD);
QuarterRound(ref chacha20.State2, ref chacha20.State6, ref chacha20.StateA, ref chacha20.StateE);
QuarterRound(ref chacha20.State3, ref chacha20.State7, ref chacha20.StateB, ref chacha20.StateF);
QuarterRound(ref chacha20.State0, ref chacha20.State5, ref chacha20.StateA, ref chacha20.StateF);
QuarterRound(ref chacha20.State1, ref chacha20.State6, ref chacha20.StateB, ref chacha20.StateC);
QuarterRound(ref chacha20.State2, ref chacha20.State7, ref chacha20.State8, ref chacha20.StateD);
QuarterRound(ref chacha20.State3, ref chacha20.State4, ref chacha20.State9, ref chacha20.StateE);
}
internal ChaCha20 Copy()
{
var temp = new ChaCha20()
{
State0 = State0,
State1 = State1,
State2 = State2,
State3 = State3,
State4 = State4,
State5 = State5,
State6 = State6,
State7 = State7,
State8 = State8,
State9 = State9,
StateA = StateA,
StateB = StateB,
StateC = StateC,
StateD = StateD,
StateE = StateE,
StateF = StateF
};
return(temp);
}