public byte[] Cifrar(byte[] textoCompleto, string K1, string K2)//tespers
{
//////////////////////
//LLENADO DE MARICES//
//////////////////////
So[0, 0] = "01"; So[0, 1] = "00"; So[0, 2] = "11"; So[0, 3] = "10";
So[1, 0] = "11"; So[1, 1] = "10"; So[1, 2] = "01"; So[1, 3] = "00";
So[2, 0] = "00"; So[2, 1] = "10"; So[2, 2] = "01"; So[2, 3] = "11";
So[3, 0] = "11"; So[3, 1] = "01"; So[3, 2] = "11"; So[3, 3] = "10";
Si[0, 0] = "00"; Si[0, 1] = "01"; Si[0, 2] = "10"; Si[0, 3] = "11";
Si[1, 0] = "10"; Si[1, 1] = "00"; Si[1, 2] = "01"; Si[1, 3] = "11";
Si[2, 0] = "11"; Si[2, 1] = "00"; Si[2, 2] = "01"; Si[2, 3] = "00";
Si[3, 0] = "10"; Si[3, 1] = "01"; Si[3, 2] = "00"; Si[3, 3] = "11";
///////////////////////////////////////////////////////////////////
char[] LLave1, LLave2 = new char[8];
byte[] textoCifrado = new byte[textoCompleto.Length];
for (var i = 0; i < textoCompleto.Length; i++)
{
string binario = Convert.ToString(textoCompleto[i], 2).PadLeft(8, '0');
string permutado = string.Empty;
for (var j = 0; j < IP.Length; j++)
{
permutado += binario.ElementAt(Convert.ToInt32(IP[j])); // Permutacion con IP
}
string IP1 = permutado.Substring(0, (permutado.Length / 2)); //bloque 1 de IP
string IP2 = permutado.Substring((permutado.Length / 2), (permutado.Length / 2)); //bloque 2 de IP
string nuevop = string.Empty;
string XOR = string.Empty;
for (var j = 0; j < EP.Length; j++)
{
nuevop += IP2.ElementAt(Convert.ToInt32(EP[j]));///Expandri y permutar con segundo bloque de IP
}
LLave1 = K1.ToCharArray();
char[] ParaOr = nuevop.ToCharArray();
for (var j = 0; j < EP.Length; j++)//xor con EP y K1
{
if (ParaOr[j].ToString() == LLave1[j].ToString())
{
XOR += "0";
}
else
{
XOR += "1";
}
}
string P1, P2;
P1 = XOR.Substring(0, (XOR.Length / 2));
P2 = XOR.Substring((XOR.Length / 2), (XOR.Length / 2));
//SBOXES PROCESS
int fila = 0, columna = 0;
fila = Convert.ToInt32((P1.ElementAt(0).ToString() + P1.ElementAt(3).ToString()), 2);
columna = Convert.ToInt32((P1.ElementAt(1).ToString() + P1.ElementAt(2).ToString()), 2);
string Bloque1 = So[fila, columna];
fila = Convert.ToInt32((P2.ElementAt(0).ToString() + P2.ElementAt(3).ToString()), 2);
columna = Convert.ToInt32((P2.ElementAt(1).ToString() + P2.ElementAt(2).ToString()), 2);
string Bloque2 = Si[fila, columna];
string Total = Bloque1 + Bloque2;//concatenar bloques con resultados
nuevop = string.Empty;
for (var j = 0; j < P4.Length; j++)
{
nuevop += Total.ElementAt(Convert.ToInt32(P4[j]));// permutar con P4 el resultado de SBOXES
}
XOR = string.Empty;
for (var j = 0; j < nuevop.Length; j++)
{
if (IP1[j].ToString() == nuevop[j].ToString())//xor con primer bloque de la IP
{
XOR += "0";
}
else
{
XOR += "1";
}
}
string swap = IP2 + XOR;//SWAAAP
string Parte2 = XOR;
nuevop = string.Empty;
for (var j = 0; j < EP.Length; j++)
{
nuevop += XOR.ElementAt(Convert.ToInt32(EP[j]));
}
LLave2 = K2.ToCharArray();
XOR = string.Empty;
for (var j = 0; j < EP.Length; j++)
{
if (LLave2[j].ToString() == nuevop[j].ToString())
{
XOR += "0";
}
else
{
XOR += "1";
}
}
P1 = XOR.Substring(0, (XOR.Length / 2));
P2 = XOR.Substring((XOR.Length / 2), (XOR.Length / 2));
fila = 0; columna = 0;
fila = Convert.ToInt32((P1.ElementAt(0).ToString() + P1.ElementAt(3).ToString()), 2);
columna = Convert.ToInt32((P1.ElementAt(1).ToString() + P1.ElementAt(2).ToString()), 2);
Bloque1 = So[fila, columna];
fila = Convert.ToInt32((P2.ElementAt(0).ToString() + P2.ElementAt(3).ToString()), 2);
columna = Convert.ToInt32((P2.ElementAt(1).ToString() + P2.ElementAt(2).ToString()), 2);
Bloque2 = Si[fila, columna];
Total = Bloque1 + Bloque2;
nuevop = string.Empty;
for (var j = 0; j < P4.Length; j++)
{
nuevop += Total.ElementAt(Convert.ToInt32(P4[j]));///SABER
}
XOR = string.Empty;
for (var j = 0; j < nuevop.Length; j++)
{
if (IP2[j].ToString() == nuevop[j].ToString())
{
XOR += "0";
}
else
{
XOR += "1";
}
}
Parte2 = XOR + Parte2;
byte[] IPI = new byte[IP.Length];//IP inversa
string Ordenada = "01234567";
char[] Orden = Ordenada.ToCharArray();
for (var j = 0; j < IP.Length; j++)
{
for (var h = 0; h < IP.Length; h++)
{
if (IP[h].ToString() == Orden[j].ToString())
{
IPI[j] = Convert.ToByte((h).ToString());
}
}
//IPI[j]= IP[Convert.ToInt32(Ordenada[j].ToString())];///SABER
}
string Rbinario = string.Empty;
for (var j = 0; j < Parte2.Length; j++)
{
Rbinario += Parte2.ElementAt(IPI[j]).ToString();
}
byte escrito = Convert.ToByte(Rbinario, 2);
textoCifrado[i] = escrito;
}
return(textoCifrado);
}