decrypt txt file?


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Thread: decrypt txt file?

  1. #1
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    decrypt txt file?

    I have a txt file that is encrypted.

    It has many lines of encrypted data.

    How would i parse the file then decrypt it, then the new file has the same spaces but is decrypted?
    Last edited by WeightOver2001; 02-25-2009 at 07:57 AM.

  2. #2
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    How was it encrypted?
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  3. #3
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    Quote Originally Posted by Hack View Post
    How was it encrypted?
    Printed off items from listview (XorEncrypt(listview(i)).

    Any ideas how to decrypt the file now so that it successfully decrypts yet also stays in the spaces from the original file?

    encrypted
    encrypted
    encrypted

    encrypted
    encrypted
    encrypted

    =

    test
    test
    test

    test
    test
    test

  4. #4
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    Quote Originally Posted by WeightOver2001 View Post
    (XorEncrypt(listview(i)).
    Never heard of it...is there a corresponding XorDecrypt?
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    Please use [Code]your code goes in here[/Code] tags when posting code.
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  5. #5
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    It was an example for the sake of telling you how to do it, it just encrypts the listview items one by one.... so is there a way to decrypt the entire file ?

  6. #6
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    Quote Originally Posted by WeightOver2001 View Post
    stays in the spaces from the original file?
    I am not sure exactly what you mean by that; but what you can do is read
    in the file line by line, decrypt each line and print that to a new file. If the
    line is blank then you just print it out to the new file without decrypting it.

    When you are done you will have a new file that looks just like your example.
    At that point you can even delete the old file and rename the new file to
    match the name of the old one....if you want...or you could move the old
    file to a different folder, for backup, and then rename the new one...

  7. #7
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    Why doesn't this code successfully decrypt a logfile?

    Code:
    l_FF = FreeFile
        lFF2 = FreeFile
        Open txtFile.Text For Input As #l_FF
            Do Until EOF(l_FF) = True
                Input #l_FF, l_Buf
                    l_Log = l_Buf
                    If LenB(l_Log) <> 0 Then
                    l_Path = RC4HexDecrypt(l_ProfileName, txtPass.Text)
                    Open strPath For Output As #lFF2
                    Print #lFF2, l_Path
                    Close #lFF2
                End If
            Loop
        Close #l_FF
    Its using the RC4HexEncrypt/Decrypt module you made.
    Last edited by WeightOver2001; 02-25-2009 at 07:57 AM.

  8. #8
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    So many problems, where do I start???

    First - FreeFile returns the next available file number, so:
    l_FF = FreeFile
    lFF2 = FreeFile
    assigns the same file number to both l_FF and lFF2

    Next - Input # is for reading in individual values from the file
    if you want to read an entire line you need to use Line Input #
    Next - LenB() is the wrong function for ordinary strings use Len() instead
    Next - RC4HexDecrypt is not decrypting what was read from the file
    it is decrypting the same value each time, whatever is in l_ProfileName
    you should change this to l_Log
    Next - You keep opening, printing, and closing your output file for each item
    read from the Input file. This is not only slower because you keep opening
    and closing the file; but it also resets the file pointer so each new item
    overwrites the old item. When you are done all you will have is the last thing
    written to the file.
    Next - you included the print to the output file inside your IF/EndIF block so
    now only the Decrypted Data is written to the new file. Any empty lines
    used for spacing will not make it into the new file. Basically you lose your
    spacing.
    FYI: your variable naming is incorrect and inconsistant.
    A few tips:
    - Use either underscores or Capitalization to seperate words
    - Ex: FirstName or first_name ... strBuf or str_buf ... lIndex or l_index
    - Be consistant, either use underscores or don't, and don't mix the two
    - don't use the same prefix letters for different data types, 'l' usually means
    Long, but you used it for both longs and strings
    - I don't use prefix letters on simple control variables, like variables used
    as loop counters, or simple string buffers, like I for my For/Next loops and
    buf for a simple string buffer.
    - Most important is to be consistant. Years later if you need to modify a piece
    of old code, it's nice to not have to waste time trying to figure out what each
    variable was used for.

    Ok now for the revised version of your routine. I made it a Sub for testing and
    I did not bother to use a form with controls, so I change txtFile and txtPass
    to just String variables and hard coded the file names and password. I didn't
    have the password you used to create your test data so my results were not
    very readable, but it ran and correctly created the new file 'logfile2.log'
    Code:
    Sub DecryptFile()
    
      Dim txtFile As String
      Dim txtPass As String
      Dim strPath As String
      Dim buf As String
      Dim log As String
      Dim lFF As Long
      Dim lFF2 As Long
      
      txtPass = "409"
      txtFile = App.Path & "\logfile.log"
      strPath = App.Path & "\logfile2.log"
      
      'open Input file
      lFF = FreeFile
      Open txtFile For Input As #lFF
      'open output file
      lFF2 = FreeFile
      Open strPath For Output As #lFF2
      
      'read through the input file
      Do Until EOF(lFF) = True
        Line Input #lFF, buf
        log = Trim$(buf)
        'if there is data then decrypt it
        If Len(Log) <> 0 Then
          buf = RC4HexDecrypt(log, txtPass)
        End If
        'write the line to output file
        Print #lFF2, buf
      Loop
      'all done so close files
      Close #lFF, #lFF2
    
    End Sub

  9. #9
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    Feb 2009
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    Thanks it semi-works. Why does it decrypt only some of it? Is because how its being printed off, can their not be a space?

    ~decrypt
    type: vH0> cE
    registered: ;b|'ß;
    user: *
    date: .

    ~what it is
    type: xaQ2
    registered: 24654-45423-35353
    user: Weight
    date: 2009

    ~encrypted
    AB58CBC34899AAB58CD5684954899AAB58C
    BC3D564899AAB58C84954899AAB58C
    4899AAB58CBC3D5684954899AAB58C
    99BC3D5684954899AAB54899AAB58C8C

  10. #10
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    What is the password that you used to encrypt it.

  11. #11
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    I solved the problem, thanks for the help.
    Last edited by WeightOver2001; 02-17-2009 at 01:04 AM.

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