If using NTFS, does secure delete overwrite the master file table entry for the file being deleted?
I'm also curious about the operation of secure delete when a small number, such as one, of passes is specified. Is it always using the same pattern for overwriting for a given pass -- pass 1 always uses pattern A, pass 2 always uses pattern B, etc. -- or does it use random values? There are certain things I like to delete in a secure way, at least more secure than a simple delete, but don't really want to spend the time needed for multiple passes. If Opus is always using the same pattern on the first pass, that's not really all that secure. If using only one pass it would be better to use random data. I'm curious about how secure a single pass secure delete really is.
The first three passes are random. Opus uses a version of the "Gutmann method" which apparently has been proven scientifically, or something. As far as I can see one or two passes of random overwriting should be enough
This section of the manual is somewhat vague, at least for those who want to know what's really going on behind the curtain. I asked the question because it was not addressed by the manual.
The Gutmann method was designed for back in the very old days of MFM drives that did not lie about their geometry. Gutmann himself has said that the method he devised for back then is pointless today. Without specific knowledge of what's really going on inside the drive -- which is virtually impossible today -- the best you can do is overwrite the file once with random data, then delete it. It sounds as though this is what happens if only one pass is made.
The question about the NTFS file table entry has still not been answered. It certainly is not addressed in the manual.
I agree, the Gutmann method is ridiculous overkill. We implemented it because that's what the people who asked for secure delete seemed to expect. Personally I think overwriting once with any sort of data, random or otherwise, would be fine.
No, Opus doesn't mess with NTFS file tables. If you are storing "sensitive" data in your file names as well as in the files themselves, you should probably rename them before deleting
May I then suggest a change for the future. Change the name of the file to some random string of characters that is at least as long as the original file name. Then delete the newly renamed file. That should obliterate the file name as well as the file contents.
Actually I just checked the code and we already do this - the file is renamed to a randomly generated name (of as many characters as is possible) before being deleted.
Up front:
I know this is a very old thread, but my post is also about randomizing names when secure deleting files.
When running recovery tools, they will show long random file names, which is fine.
However, they also show the folder names where they were located. Folder names often reveal the nature of the deleted files.
I don't know if the below idea is workable at all, but what about the following:
randomize the file name(s), like now, but maybe with a maximum of -say- 230 characters
create a temp folder with a random name *
move the file(s) to that folder
delete it/them there.
(* or move files to a user created temp folder e.g. a folder named ZZZZZZZZZZZ)
this way recovery tools at least won't show what the files were about.
Obviously it is not necessary to secure delete each and every file, so I use a context menu item
Delete Secure=1 ALL QUIET NORECYCLE FORCE
Just an idea.
Today many drives are SSD and secure erase files (not wiping drives) isn't really possible.
Randomizing folder names (and file names) may then be an option.
Yes it does. One needs to use dedicated 3rd party tool to avoid that, but this again requires another installation.
I have no knowledge of scripting, but I assume(!) it should be possible to have a script that
-move files to a specific folder (like above 'Z'-folder, i.e. a temp folder with a fixed name)
-then select and secure delete that folder
WipeFile, natively portable, includes randomly renaming of files and folders. No doubt other tools can do this as well, but WipeFile is very small, free, is fast and it can be added to the context menu.
At first launch, settings:
Integrate into the user context menu
Integrate into the 'Send tor menu
v12.9.1 "The Secure Delete function now moves files to a temporary folder (with random name) before deleting them, to try to stop their original location being visible in recovery tools."
Thank you, that works fine!
formatted a drive using Format Q: /FS:NTFS /P:2
Recuva deep scan (results left)
copied folders to the drive and securely deleted them
Recuva deep scan again (results right)
recovery may be possible, but the recovery folders could not be renamed (that is to say, I could not) nor handled in any other way.
