RC4

SUBMITTED BY: Guest

DATE: May 27, 2013, 12:28 p.m.

FORMAT: Text only

SIZE: 3.3 kB

Raw Download

HITS: 1606

Report
  1. ;===============================================================================
  2. ;
  3. ; Function Name: _StringEncryptRC4
  4. ; Description:: Encrypts text using RC4 Encryption
  5. ; Parameter(s): $text, $encryptkey
  6. ; Requirement(s): AutoIt
  7. ; Return Value(s): Encrypted String
  8. ; Author(s): RazerM
  9. ;
  10. ;===============================================================================
  11. ;
  12. Func _StringEncryptRC4($text, $encryptkey)
  13. Local $sbox[256]
  14. Local $key[256]
  15. Local $temp
  16. Local $a
  17. Local $i
  18. Local $j
  19. Local $k
  20. Local $cipherby
  21. Local $cipher
  23. $i = 0
  24. $j = 0
  26. __RC4Initialize($encryptkey, $key, $sbox)
  28. For $a = 1 To StringLen($text)
  29. $i = Mod(($i + 1),256)
  30. $j = Mod(($j + $sbox[$i]),256)
  31. $temp = $sbox[$i]
  32. $sbox[$i] = $sbox[$j]
  33. $sbox[$j] = $temp
  35. $k = $sbox[Mod(($sbox[$i] + $sbox[$j]),256)]
  37. $cipherby = BitXOR(Asc(StringMid($text, $a, 1)),$k)
  38. $cipher = $cipher & Chr($cipherby)
  39. Next
  41. Return _StringToHexEx($cipher)
  42. EndFunc ;==>_StringEncryptRC4
  44. ;===============================================================================
  45. ;
  46. ; Function Name: _StringDecryptRC4
  47. ; Description:: Decrypts text using RC4 Encryption
  48. ; Parameter(s): $text, $encryptkey
  49. ; Requirement(s): AutoIt
  50. ; Return Value(s): Decrypted String
  51. ; Author(s): RazerM
  52. ; Note(s): RC4 uses the same algorithm to encrypt and decrypt
  53. ;
  54. ;===============================================================================
  55. ;
  57. Func _StringDecryptRC4($text, $encryptkey)
  58. Local $sbox[256]
  59. Local $key[256]
  60. Local $temp
  61. Local $a
  62. Local $i
  63. Local $j
  64. Local $k
  65. Local $cipherby
  66. Local $cipher
  67. $text = _HexToStringEx($text)
  69. $i = 0
  70. $j = 0
  72. __RC4Initialize($encryptkey, $key, $sbox)
  74. For $a = 1 To StringLen($text)
  75. $i = Mod(($i + 1),256)
  76. $j = Mod(($j + $sbox[$i]),256)
  77. $temp = $sbox[$i]
  78. $sbox[$i] = $sbox[$j]
  79. $sbox[$j] = $temp
  81. $k = $sbox[Mod(($sbox[$i] + $sbox[$j]),256)]
  83. $cipherby = BitXOR(Asc(StringMid($text, $a, 1)),$k)
  84. $cipher = $cipher & Chr($cipherby)
  85. Next
  86. Return $cipher
  87. EndFunc ;==>_StringDecryptRC4
  90. ; Helper function
  91. Func __RC4Initialize($strPwd, ByRef $key, ByRef $sbox)
  92. Dim $tempSwap
  93. Dim $a
  94. Dim $b
  96. $intLength = StringLen($strPwd)
  97. For $a = 0 To 255
  98. $key[$a] = Asc(StringMid($strPwd, (Mod($a,$intLength))+1, 1))
  99. $sbox[$a] = $a
  100. Next
  102. $b = 0
  103. For $a = 0 To 255
  104. $b = Mod($b + $sbox[$a] + $key[$a],256)
  105. $tempSwap = $sbox[$a]
  106. $sbox[$a] = $sbox[$b]
  107. $sbox[$b] = $tempSwap
  108. Next
  109. EndFunc ;==>__RC4Initialize
  111. Func _HexToStringEx($strHex)
  112. Return BinaryToString("0x" & $strHex)
  113. EndFunc ;==>_HexToStringEx
  115. Func _StringToHexEx($strChar)
  116. Return Hex(StringToBinary($strChar))
  117. EndFunc
comments powered by Disqus