CRC32 Test

[Dazed_and_Confused]

Been doing some heavy reading in TDS-3 manual. Kind of reminds me of War & Peace. ;) I'm loving this tool more every day. Regarding the CRC32 test, four questions for anyone, please.

1. What is the downside to adding files to the CRCFILES.TXT file, if any, besides increased scan time?
2. Is there a way to add an entire directory using wildcards? (.../directory/*.exe)
3. Is my understanding correct that when I first add a new file to CRCFILES.TXT and run the CRC32 test, TDS saves the checksum of the file somewhere on my PC and then compares that original checksum to checksums created during subsequent scans of that file?
4. Are there any other files not in the default CRCFILES.TXT that one should consider adding?

Thanks a bunch,

D&C

[Jooske]

The TDS sticky threads contains several very instructive CRC instructions threads, you might find new answers there!

[Dazed_and_Confused]

Jooske,

Thanks! I guess I don't visit this board as much as I should - I've never got around to reading the Sticky Threads before. Lots of good info there.

[Dazed_and_Confused]

One more questions regarding CRC32 that I didn't see addressed in the sticky threads (unless I missed it) - Is there a way to indicate in the "crcfiles" text file that you want every file in the directory scanned? Wildcards (*.*) don' seem to work.

[FanJ]

Hi D&C,

About your question for all files in a directory.
No, you cannot do it with the CRC32-feature in TDS-3.
However: there are other means to do it.
For example: you can use the free Directory Printer from Karen:
http://www.karenware.com/powertools/ptdirprn.asp

It is a nice tool that also gives you the possibility to save a list of all files in a certain directory to a text-file.
You can then copy that list into your file crcfiles.txt

Here comes an example (just only an example !!!) for my adaware directory.

First I'll try to give a screenshot from Karen's Directory Printer showing you how I have set it up to give me a list of all files in the adaware directory (not the ones in the sub-dirs), with their full path.
Remember: files in crcfiles.txt have to be listed with their full path.

[FanJ]

And here is the list that it gave me:

c:\Program Files\Lavasoft\Ad-aware 6\aawhelper.dll
c:\Program Files\Lavasoft\Ad-aware 6\Ad-aware.exe
c:\Program Files\Lavasoft\Ad-aware 6\Ad-watch.exe
c:\Program Files\Lavasoft\Ad-aware 6\alert.wav
c:\Program Files\Lavasoft\Ad-aware 6\default.det
c:\Program Files\Lavasoft\Ad-aware 6\description.ini
c:\Program Files\Lavasoft\Ad-aware 6\INSTALL.LOG
c:\Program Files\Lavasoft\Ad-aware 6\manual.chm
c:\Program Files\Lavasoft\Ad-aware 6\mp
c:\Program Files\Lavasoft\Ad-aware 6\prefs.ini
c:\Program Files\Lavasoft\Ad-aware 6\reflist.ref
c:\Program Files\Lavasoft\Ad-aware 6\reflist.ref.old
c:\Program Files\Lavasoft\Ad-aware 6\sites.txt
c:\Program Files\Lavasoft\Ad-aware 6\unregaaw.exe
c:\Program Files\Lavasoft\Ad-aware 6\Unwise.exe

[FanJ]

-{ Quote: "Been doing some heavy reading in TDS-3 manual. Kind of reminds me of War & Peace. ;) I'm loving this tool more every day. Regarding the CRC32 test, four questions for anyone, please.

1. What is the downside to adding files to the CRCFILES.TXT file, if any, besides increased scan time?" }-

That depends on how much you would like to have listed in it.
I myself have about some 200 files listed in it, and I don't see any downside (and this is an old PC).

-{ Quote: "

3. Is my understanding correct that when I first add a new file to CRCFILES.TXT and run the CRC32 test, TDS saves the checksum of the file somewhere on my PC and then compares that original checksum to checksums created during subsequent scans of that file?" }-

Yep :)

-{ Quote: "
4. Are there any other files not in the default CRCFILES.TXT that one should consider adding?" }-

For example your HOSTS file, the adaware reflist, important files of your AV, etc.
Your choice ;)

I hope this helps a little bit.
Cheers, Jan.

[Dazed_and_Confused]

Something must not be working right with my CRC test. I created a text file using Notepad, and inside it I place the text "This is a test.", and saved the file as "D:\My Documents\Temp\test.txt" and added this path to crcfiles.txt. Next I ran a System CRC32 Test. The TDS screen indicated the file count had increased by one, and fininshed without a problem. I then edited the "test.txt" file by adding a single character ("1") at the end of the original sentence, and saved the file. Re-ran the CRC32 test, and it did not catch the change. Should it have?

[FanJ]

Hi D&C,

Please have a look at this thread:
http://www.wilderssecurity.com/showthread.php?t=25306

You will see there that on a few systems a certain sub-dir might be missing.
That thread tells you more about it ;)

[Dazed_and_Confused]

FanJ,

Thanks. After I posted the above, I remembered reading something about a bug, so I went back to the sticky threads, and found that. It's working now.

By the way, I'm in the process of installing Karen's Directory Printer. Thanks!

[FanJ]

You're welcome :)

I'm glad it's working now for you ! :D

Cheers, Jan.