'From:  "delly20fr" <adonai@f...> Tue Oct 8, 2002  4:28 am
'Subject:  RC4 encryption for RapidQ - enjoy and be secure ;)
'
'RC4 STRONG ENCRYPTION (key until 2048 bits) for RapidQ
'designed by Del_Armg0 for rQcommunities - Enjoy this fast and secure algo.
'and if u find it usefull just give credits (rc4 is used by IE, netscape, ...)
'
'happy coding !
'
'

$APPTYPE GUI
$TYPECHECK ON
$OPTIMIZE ON

$INCLUDE "RAPIDQ.INC"

'--------- """""""""""""""""""" ---------'---------
'--------- """""""""""""""""""" ---------'---------

DECLARE SUB Button1Click(Sender AS QBUTTON)
DECLARE SUB Button2Click(Sender AS QBUTTON)

'--------- """""""""""""""""""" ---------'---------
'--------- """""""""""""""""""" ---------'---------

DECLARE FUNCTION Rc4$(s$) AS STRING
DECLARE FUNCTION Rc4K(InitFlag) AS INTEGER
DECLARE SUB Rc4Init(Key$)


'--------- """""""""""""""""""" ---------

DIM se(255) AS INTEGER  'S-Box is here
DIM ke(255) AS INTEGER

DIM KeyLen9 AS INTEGER
DIM KeyPtr9 AS INTEGER
DIM StringLen9 AS INTEGER

DIM Xq AS INTEGER
DIM Cq AS INTEGER
DIM Iq AS INTEGER
DIM Jq AS INTEGER
DIM Tq AS INTEGER

DIM InitFLag AS INTEGER
DIM Key$ AS STRING
DIM Encrypted$YY AS STRING
DIM Clear$YY AS STRING

DIM r$ AS STRING
DIM s$ AS STRING

DIM mode9 AS INTEGER


'--------- """""""""""""""""""" ---------'---------
'--------- """""""""""""""""""" ---------'---------

CREATE Form AS QFORM
    Caption = " RC4 Encryption for RapidQ - by Del_Armg0 - October.2002"
    Width = 435
    Height = 422
    Center
    CREATE RichEdit1 AS QRICHEDIT
        Left = 2
        Top = 5
        Width = 422
        Height = 163
        PlainText = 1
        ShowHint = 1
        Hint = "Input text - Clear"
        AddStrings "Software coded by Del_Armg0 / Delly_ // mailto: adonai@f... // -- // ceci est un test - this is a test - the RC4/ArcFour encryption -- KEY_SIZE Max. Value = 2048 bits / 256 octets"
    END CREATE
    CREATE RichEdit2 AS QRICHEDIT
        Left = 2
        Top = 197
        Width = 422
        Height = 193
        PlainText = 1
        ShowHint = 1
        Hint = "Output text - RC4 Encrypted"
        TabOrder = 1
    END CREATE
    CREATE Edit1 AS QEDIT
        Text = "enter_your_password_here"
        Left = 2
        Top = 170
        Width = 320
        TabOrder = 2
    END CREATE
    CREATE Button1 AS QBUTTON
        Caption = "ENCry"
        Left = 330
        Top = 170
        Width = 43
        TabOrder = 3
        OnClick = Button1Click
    END CREATE
    CREATE Button2 AS QBUTTON
        Caption = "DECry"
        Left = 377
        Top = 170
        Width = 43
        TabOrder = 3
        OnClick = Button2Click
    END CREATE
END CREATE

Form.BorderStyle = bsDialog
Form.ShowModal

'--------- """""""""""""""""""" ---------'---------
'--------- """""""""""""""""""" ---------'---------

'--------- """""""""""""""""""" ---------

SUB Button1Click(Sender AS QBUTTON)

    mode9 = 1

    RichEdit2.Clear

    s$ = ""
    r$ = ""
    KeyPtr9 = 0
    Xq = 0
    Cq = 0
    Iq = 0
    Jq = 0
    Tq = 0
    InitFLag = 0
    KeyLen9 = 0
    StringLen9 = 0


    Key$ = Edit1.Text
    Clear$YY = RichEdit1.Text

    Rc4Init(Key$)

    Encrypted$YY = Rc4$(Clear$YY)

    DIM tt1 AS INTEGER
    DIM kar AS STRING
    DIM ascc AS INTEGER
    DIM karall AS STRING
    DIM karascc AS STRING

    karall = ""
    karascc = ""
    ascc = 0
    kar = ""
    tt1 = 0


    FOR tt1 = 1 TO LEN(Encrypted$YY)
        kar = MID$(Encrypted$YY , tt1 , 1)
        ascc = ASC(kar)
        karascc = STR$(ascc)
        IF LEN(karascc) = 1 THEN
            karascc = "00" + karascc
        ELSEIF LEN(karascc) = 2 THEN
            karascc = "0" + karascc
        ELSEIF LEN(karascc) = 3 THEN
            karascc = karascc
        END IF
        karall = karall + karascc
    NEXT

    RichEdit2.Text = "@___DEL_A_StartOfFile___|>" + CHR$(13) + CHR$(10) + karall + CHR$(13) + CHR$(10) + "@___DEL_A_EndOfFile___|>"

END SUB

'--------- """""""""""""""""""" ---------
'--------- """""""""""""""""""" ---------

SUB Button2Click(Sender AS QBUTTON)

    mode9 = 2

    RichEdit1.Clear

    s$ = ""
    r$ = ""
    KeyPtr9 = 0
    Xq = 0
    Cq = 0
    Iq = 0
    Jq = 0
    Tq = 0
    InitFLag = 0
    KeyLen9 = 0
    StringLen9 = 0


    Key$ = Edit1.Text
    Encrypted$YY = RichEdit2.Text

    DIM tt2 AS INTEGER
    DIM kar2 AS STRING
    DIM ascc2 AS INTEGER
    DIM karal1 AS STRING
    DIM karal2 AS STRING

    karal1 = ""
    karal2 = ""
    ascc2 = 0
    kar2 = ""
    tt2 = 0

    DIM manip$ AS STRING
    DIM mathmo AS INTEGER

    manip$ = REPLACESUBSTR$(Encrypted$YY , "@___DEL_A_StartOfFile___|>" , "")
    manip$ = REPLACESUBSTR$(manip$ , "@___DEL_A_EndOfFile___|>" , "")
    manip$ = REPLACESUBSTR$(manip$ , CHR$(13) + CHR$(10) , "")

    Encrypted$YY = manip$


    mathmo = LEN(Encrypted$YY)

    FOR tt2 = 1 TO(mathmo) STEP 3
        kar2 = MID$(Encrypted$YY , tt2 , 3)
        ascc2 = VAL(kar2)
        karal1 = CHR$(ascc2)
        karal2 = karal2 + karal1

    NEXT


    Encrypted$YY = karal2

    Rc4Init(Key$)

    Clear$YY = Rc4$(Encrypted$YY)

    RichEdit1.Text = Clear$YY

END SUB

'--------- """""""""""""""""""" ---------
'--------- """""""""""""""""""" ---------'---------

FUNCTION Rc4$(s$)

    StringLen9 = LEN(s$)

    FOR Xq = 1 TO StringLen9
        Cq = ASC(MID$(s$ , Xq , 1))
        ke() = Rc4K(0) '<---- prob here if ke without ( ) !
        r$ = r$ + CHR$(Cq XOR ke()) '<---- prob here if ke without ( ) !
    NEXT

    Rc4$ = r$

END FUNCTION

'--------- """""""""""""""""""" ---------'---------

SUB Rc4Init(Key$)

    KeyLen9 = LEN(Key$)

    FOR Iq = 0 TO 255
        se(Iq) = Iq
        KeyPtr9 = KeyPtr9 + 1
        ke(Iq) = ASC(MID$(Key$ , KeyPtr9 , 1))
        IF KeyPtr9 = KeyLen9 THEN
            KeyPtr9 = 0
        END IF
    NEXT

    FOR Iq = 0 TO 255
        Jq = (Jq + se(Iq) + ke(Iq)) MOD 256
        SWAP se(Iq) , se(Jq)
    NEXT

    Iq = Rc4K(1)

END SUB

'--------- """""""""""""""""""" ---------'---------

FUNCTION Rc4K(InitFLag)

    STATIC iq AS INTEGER
    STATIC jq AS INTEGER

    IF InitFLag THEN
        iq = 0
        jq = 0
    ELSE
        iq = (iq + 1) MOD 256
        jq = (jq + se(iq)) MOD 256
        SWAP se(iq) , se(jq)
        Tq = (se(iq) + se(jq)) MOD 256
        Rc4K = se(Tq)
    END IF

END FUNCTION