Perm File Deletion

[dapanther]

Hi Everyone,
I just wanted to know if anyone had a snip or two of code to handle file deletion. Now before you give me a object.delete() call or something, I am referring to a more perm delete something along the lines of DOD specs.

I was thinking that if I created a random number generator function and use that to generate the data to fill the file and then a function to read the file and populate it with the garbage data. Then rename the file using the same number generator so that the filename changes.

Is this basically what I need to achieve so that the file would be alot harder to recover? Or is there more to it than this?

Another way I was thinking was to write something in assembler that would just change the memory location, but I thought that would in essence though still leave the remenants of the file out there.

Any ideas?

Dapanther...

 

[IngisKahn]

The DoD standard for non TOP SECRET docs is to overwrite the file with a single char, the overwrite it again with that chars compliment then to overwrite it with random data. The best you can do with a file name is to change it a number of times. The standard is to replace all non .s in the name with As then Bs and so 26 times. e.g. foo.txt becomes AAA.AAA

This works great on FAT32 and normal files on NTFS, but if the NTFS file is compressed or encrypted then it will not work. When you overwrite a compressed or encrypted file new blocks are allocated and the old contents remain. SO... The only way to deal with compressed or encrypted files is to use the win32 defragmentation API function to get the clusters belonging to the file and have raw access to overwrite them.

 

[Richard Crist]

Useful utility?

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