Question

I have inherited some legacy vb6 code. It’s a tool which generates a local admin password for a windows pc. The password is supposed to contain only a limited set of characters. The tool works fine.. as long as it’s not run on chinese or russian PCs. There, it generates weird passwords that nobody can type in. Of course it has something to do with the current operating system culture. The Chr(CharCode) function returns some weird characters on those systems. Anyone has a clue on how to make this culture invariant? I only want the tool to generate passwords with standard ASCII characters.

Function generatePassword(PASSWORD_LENGTH)
Dim NUMLOWER, NUMUPPER, LOWERBOUND, UPPERBOUND, LOWERBOUND1, UPPERBOUND1, SYMLOWER, SYMUPPER
Dim newPassword, count, pwd
Dim pCheckComplex, pCheckComplexUp, pCheckComplexLow, pCheckComplexNum, pCheckComplexSym, pCheckAnswer

  NUMLOWER = 48     ' 48 = 0
  NUMUPPER = 57     ' 57 = 9
  LOWERBOUND = 65   ' 65 = A
  UPPERBOUND = 90   ' 90 = Z
  LOWERBOUND1 = 97  ' 97 = a
  UPPERBOUND1 = 122 ' 122 = z
  SYMLOWER = 33     ' 33 = !
  SYMUPPER = 46     ' 46 = .
  pCheckComplexUp = 0  ' used later to check number of character types in password
  pCheckComplexLow = 0 ' used later to check number of character types in password
  pCheckComplexNum = 0 ' used later to check number of character types in password
  pCheckComplexSym = 0 ' used later to check number of character types in password

  ' initialize the random number generator
  Randomize

  newPassword = ""
  count = 0
  Do Until count = PASSWORD_LENGTH
    ' generate a num between 2 and 10

    ' if num <= 2 create a symbol
    If Int((10 - 2 + 1) * Rnd + 2) <= 2 Then
      'pwd = Int( ( SYMUPPER - SYMLOWER + 1 ) * Rnd + SYMLOWER )

      pwd = Int((UPPERBOUND1 - LOWERBOUND1 + 1) * Rnd + LOWERBOUND1)

      ' if num is between 3 and 5 create a lowercase
    ElseIf Int((10 - 2 + 1) * Rnd + 2) > 2 And Int((10 - 2 + 1) * Rnd + 2) <= 5 Then
      pwd = Int((UPPERBOUND1 - LOWERBOUND1 + 1) * Rnd + LOWERBOUND1)

      ' if num is 6 or 7 generate an uppercase
    ElseIf Int((10 - 2 + 1) * Rnd + 2) > 5 And Int((10 - 2 + 1) * Rnd + 2) <= 7 Then
      pwd = Int((UPPERBOUND - LOWERBOUND + 1) * Rnd + LOWERBOUND)

    Else
      pwd = Int((NUMUPPER - NUMLOWER + 1) * Rnd + NUMLOWER)
    End If

    If Chr(pwd) <> "l" And Chr(pwd) <> "I" Then
      newPassword = newPassword + Chr(pwd)

      count = count + 1
    End If

    'Check to make sure that a proper mix of characters has been created.  If not discard the password.
    If count = (PASSWORD_LENGTH) Then
      For pCheckComplex = 1 To PASSWORD_LENGTH
        'Check for uppercase
        If Asc(Mid(newPassword, pCheckComplex, 1)) > 64 And Asc(Mid(newPassword, pCheckComplex, 1)) < 90 Then
          pCheckComplexUp = 1
        'Check for lowercase
        ElseIf Asc(Mid(newPassword, pCheckComplex, 1)) > 96 And Asc(Mid(newPassword, pCheckComplex, 1)) < 123 Then
          pCheckComplexLow = 1
        'Check for numbers
        ElseIf Asc(Mid(newPassword, pCheckComplex, 1)) > 47 And Asc(Mid(newPassword, pCheckComplex, 1)) < 58 Then
          pCheckComplexNum = 1
        'Check for symbols
        ElseIf Asc(Mid(newPassword, pCheckComplex, 1)) > 32 And Asc(Mid(newPassword, pCheckComplex, 1)) < 47 Then
          pCheckComplexSym = 1
        End If
      Next

      'Add up the number of character sets.  We require 3 or 4 for a complex password.
      pCheckAnswer = pCheckComplexUp + pCheckComplexLow + pCheckComplexNum + pCheckComplexSym

      If pCheckAnswer < 3 Then
        newPassword = ""
        count = 0
      End If
    End If
  Loop
  'The password is good so return it
  generatePassword = newPassword
End Function

Answer 1

Deanna’s comment is correct. Just change Chr to ChrW and change Asc to AscW.

• ChrW accepts Unicode code points
• Chr accepts “ANSI” code points, and the meaning of a particular code point will be different depending on the system code page. For example on Chinese and Russian code pages.