[Delphi]Енкрипција на текст

[Coolzrock]

unit unRC4;
 
interface
 
type
  PByteArray = ^TByteArray;
  TByteArray = Array [0..32767] Of Byte;
 
  TRC4 = class
  private
    D               : array[Byte] of Byte;
    I,J             : Byte;
    procedure Init(const Key: string);
    procedure Done;
    procedure Code(Source, Dest: pChar; Count: Integer);
  public
    function Encrypt(S: pChar; const Password: string): AnsiString;
    function Decrypt(S: pChar; const Password: string): AnsiString;
  end;
 
implementation
 
{ TRC4.Encrypt
  This function will return the text(S) encrypted with the chosen password. }
function TRC4.Encrypt(S: pChar; const Password: string): AnsiString;
begin
  SetLength(Result, Length(S));
  Init(Password);
  Code(pChar(S), pChar(Result), Length(S));
  Done;
end;
 
{ TRC4.Decrypt
  This function will return the text(S) decrypted with the chosen password. }
function TRC4.Decrypt(S: pChar; const Password: string): AnsiString;
begin
  SetLength(Result, Length(S));
  Init(Password);
  Code(pChar(S), pChar(Result), Length(S));
  Done;
end;
 
{ TRC4.Init
  This routine will prepare the encryption/decryption. }
procedure TRC4.Init(const Key: string);
var
  R, S, T, K        : Byte;
  U,L               : Integer;
  DummyArray        : array [0..1599] of Char;
begin
{$R-}
{$Q-}
  L := Length(Key);
  I := 0;
  J := 0;
  R := 0;
  U := 0;
  for S := 0 to 255 do
    D[S] := S;
  for S := 0 to 255 do
  begin
    if (U < L) then
      K := PByteArray(Key)[u]
    else
      K := 0;
    Inc(U);
    if (U >= L) then
      U := 0;
    Inc(R, D[S] + K);
    T    := D[S];
    D[S] := D[R];
    D[R] := T;
  end;
  Code(@DummyArray, @DummyArray, 1600);
end;
 
{ TRC4.Done
  This routine will clean the variables used when encrypting/decrypting. }
procedure TRC4.Done;
begin
  FillChar(D, sizeOf(D), 0);
  FillChar(I, sizeOf(I), 0);
  FillChar(J, sizeOf(J), 0);
end;
 
{ TRC4.Code
  This routine will encrypt the text. }
procedure TRC4.Code(Source, Dest: pChar; Count: Integer);
var
  S                 : Integer;
  T                 : Byte;
begin
  for S := 0 to (Count - 1) do
  begin
    Inc(I);
    T := D[i];
    Inc(J, T);
    D[i] := D[J];
    D[J] := T;
    Inc(T, D[i]);
    Byte(Dest[S]) := Byte(Source[S]) xor D[T];
  end;
end;
 
end.

 

[Aleks]

Ако веќе пастираш туѓи кодови наведи ја нивната локација од каде си ги нашол а не вака.

 

[gOJDO]

http://topic.csdn.net/u/20081105/16/e37fd020-c656-455b-a69e-3b9b5a9e5b81.html