//Autor: Artur Czekalski (Sator)  www.epokaY.net/artur  artur@epokaY.net
//Szyfrowanie RC4
import std.c.windows.windows; //GetTickCount
import std.stdio; //writefln
//---------------------------------------------------------------------------
const uint gDlTablicy = 10000000;
ubyte gTablica[gDlTablicy];
//---------------------------------------------------------------------------
void SzyfrujRC4(const uint DlTablicy, ubyte *Tablica,
                const uint DlHasla, const ubyte *Haslo)
{
 uint i, j, x;  uint perm[256]; //permutacja
 //---inicjalizacja---
 for (i=0; i<256; ++i) perm[i] = cast(ubyte)i;
 j = 0;
 for (i=0; i<256; ++i)
  {j = (j + perm[i] + Haslo[i % DlHasla]) % 256;
   x=perm[i];  perm[i]=perm[j];  perm[j]=x; //perm[i]<->perm[j]
  }
 //---szyfrowanie---
 i = 0;
 uint Index = 0;
 while (Index < DlTablicy)
  {
   i = (i+1) % 256; //[A3]
   j = (j + perm[i]) % 256; //[B2]
   x=perm[i];  perm[i]=perm[j];  perm[j]=x; //perm[i]<->perm[j]
   Tablica[Index++] ^= perm[(perm[i]+perm[j]) % 256]; //XOR
  } 
};
//===========================================================================
int main(char[][] args)
{int i, czas;
 char Haslo[16] = "sator";
 uint DlHasla = 5;
 //---Spr.
 for (i=0; i<10; ++i) gTablica[i] = cast(ubyte)('a'+i);
 writefln("Przed szyfrowaniem:");  for (i=0; i<10; ++i) printf("%02X ", cast(int)gTablica[i]);
 SzyfrujRC4(gDlTablicy, cast(ubyte*)gTablica,  DlHasla, cast(ubyte*)Haslo);
 writefln("\nPo szyfrowaniu:");  for (i=0; i<10; ++i) printf("%02X ", cast(int)gTablica[i]);
 //---Test
 for (i=0; i<gDlTablicy; ++i) gTablica[i] = cast(ubyte)0;
 czas = GetTickCount();
 for (i=0; i<500; ++i)
  SzyfrujRC4(gDlTablicy, cast(ubyte*)gTablica,  DlHasla, cast(ubyte*)Haslo);
 czas = GetTickCount() - czas;
 //---
 writefln("\nPo szyfrowaniu:");  for (i=0; i<25; ++i) printf("%02X ", cast(int)gTablica[i]);
 writef("\nDigitalMars Dv2: Czas=%d", czas);
 getchar();  return 0;
}