by matt.janus (1 Submission)
Category: Encryption
Compatability: Visual Basic 5.0
Difficulty: Beginner
Date Added: Wed 3rd February 2021
Rating: 
(2 Votes)
ive seen lot's of people's input on bad and insecure some encryption codes. this is one i put togeather. im wondering how (in)secure it is. please give me your opinion so i can further improve on it. you dont need to vote, i just want feedback.
sorry about the repost. i messed up the last one.
VBcodersFunction RandNum(min, max)
reRand:
DoEvents
Randomize
X = (Rnd * (max * 10)) / 10
If X > max Then GoTo reRand
If X < min Then GoTo reRand
X = Format(X, "0##")
RandNum = X
End Function
Function Encrypt(theString)
Dim theLen As Long, i As Long
Dim TempStr1 As String, TempStr2 As String, TempStr3 As String
Dim finalStr As String, tempChar As String
theLen = Len(theString)
For i = 1 To theLen Step 2
TempStr1 = TempStr1 & Mid(theString, i, 1)
TempStr2 = TempStr2 & Mid(theString, i + 1, 1)
Next
TempStr3 = LCase(TempStr2 & TempStr1)
For i = 1 To theLen
curChar = Mid(TempStr3, i, 1)
Select Case curChar
Case "a"
tempChar = RandNum(969, 999)
Case "b"
tempChar = RandNum(50, 80)
Case "c"
tempChar = RandNum(939, 968)
Case "d"
tempChar = RandNum(126, 132)
Case "e"
tempChar = RandNum(901, 938)
Case "f"
tempChar = RandNum(888, 900)
Case "g"
tempChar = RandNum(81, 105)
Case "h"
tempChar = RandNum(106, 125)
Case "i"
tempChar = RandNum(133, 147)
Case "j"
tempChar = RandNum(601, 621)
Case "k"
tempChar = RandNum(148, 178)
Case "l"
tempChar = RandNum(179, 209)
Case "m"
tempChar = RandNum(209, 230)
Case "n"
tempChar = RandNum(231, 265)
Case "o"
tempChar = RandNum(622, 651)
Case "p"
tempChar = RandNum(266, 296)
Case "q"
tempChar = RandNum(297, 321)
Case "r"
tempChar = RandNum(652, 681)
Case "s"
tempChar = RandNum(322, 352)
Case "t"
tempChar = RandNum(682, 705)
Case "u"
tempChar = RandNum(353, 381)
Case "v"
tempChar = RandNum(382, 405)
Case "w"
tempChar = RandNum(406, 424)
Case "x"
tempChar = RandNum(424, 436)
Case "y"
tempChar = RandNum(437, 461)
Case "z"
tempChar = RandNum(462, 492)
Case "."
tempChar = RandNum(493, 505)
Case ","
tempChar = RandNum(506, 520)
Case "?"
tempChar = RandNum(521, 531)
Case "!"
tempChar = RandNum(532, 545)
Case " "
tempChar = RandNum(546, 600)
Case Else
tempChar = RandNum(493, 505)
End Select
DoEvents
finalStr = finalStr & tempChar
Next
finalStr = Replace(finalStr, "0", "A")
finalStr = Replace(finalStr, "1", "B")
finalStr = Replace(finalStr, "2", "C")
finalStr = Replace(finalStr, "3", "D")
finalStr = Replace(finalStr, "4", "E")
finalStr = Replace(finalStr, "5", "F")
finalStr = Replace(finalStr, "6", "G")
finalStr = Replace(finalStr, "7", "H")
finalStr = Replace(finalStr, "8", "I")
finalStr = Replace(finalStr, "9", "J")
Encrypt = finalStr
End Function
Function Decrypt(theStr)
theString = theStr
Dim theLen As Long
Dim curChar As String, tempChar As String, _
temp1 As String, temp2 As String, finalStr As String
theString = Replace(theString, "A", "0")
theString = Replace(theString, "B", "1")
theString = Replace(theString, "C", "2")
theString = Replace(theString, "D", "3")
theString = Replace(theString, "E", "4")
theString = Replace(theString, "F", "5")
theString = Replace(theString, "G", "6")
theString = Replace(theString, "H", "7")
theString = Replace(theString, "I", "8")
theString = Replace(theString, "J", "9")
theLen = Len(theString) - 1
For i = 1 To theLen Step 3
curChar = Mid(theString, i, 3)
Select Case Int(curChar)
Case 969 To 999
tempChar = "a"
Case 66 To 80
tempChar = "b"
Case 939 To 968
tempChar = "c"
Case 126 To 132
tempChar = "d"
Case 901 To 938
tempChar = "e"
Case 888 To 900
tempChar = "f"
Case 81 To 105
tempChar = "g"
Case 106 To 125
tempChar = "h"
Case 133 To 147
tempChar = "i"
Case 601 To 621
tempChar = "j"
Case 148 To 178
tempChar = "k"
Case 179 To 209
tempChar = "l"
Case 210 To 230
tempChar = "m"
Case 231 To 265
tempChar = "n"
Case 622 To 651
tempChar = "o"
Case 266 To 296
tempChar = "p"
Case 297 To 321
tempChar = "q"
Case 652 To 681
tempChar = "r"
Case 322 To 352
tempChar = "s"
Case 682 To 705
tempChar = "t"
Case 353 To 381
tempChar = "u"
Case 382 To 405
tempChar = "v"
Case 406 To 424
tempChar = "w"
Case 425 To 436
tempChar = "x"
Case 437 To 461
tempChar = "y"
Case 462 To 492
tempChar = "z"
Case 493 To 505
tempChar = "."
Case 506 To 520
tempChar = ","
Case 521 To 531
tempChar = "?"
Case 532 To 545
tempChar = "!"
Case 546 To 600
tempChar = " "
End Select
DoEvents
TempStr1 = TempStr1 & tempChar
Next
theLen = Len(TempStr1)
If theLen Mod 2 <> 0 Then
temp1 = Mid(TempStr1, 1, (theLen / 2) - 0.5)
temp2 = Mid(TempStr1, (theLen / 2) + 0.5, theLen)
theLen = Len(temp2)
Else
temp1 = Mid(TempStr1, 1, (theLen / 2))
temp2 = Mid(TempStr1, (theLen / 2) + 1, theLen)
theLen = Len(temp2)
End If
For i = 1 To theLen
finalStr = finalStr & Mid(temp2, i, 1) & Mid(temp1, i, 1)
Next
Decrypt = finalStr
End Function
