PC disk wipe software - SUPERWIPE 1.04R Note: SUPERWIPE is also a SUPER ERASER with powerful erase features. As a matter of fact, I have written a shareware program that is a PC wipe program: SUPERWIPE 1.04R . I just sent a copy to Perry Metzger. If anyone else wants a copy, let me know. Its free to Cypherpunks. There are two big problems with writing a PC disk wipe program. 1. Compressed disks. With compressed disks you don't know how long to make the write. You try putting all 1's or all 0's and the disk compressor will compress it next to nothing. In fact, it may write the wipe data to different clusters than the original file. 2. Software disk caches and even worse - hardware disk caches. - Those 256k disk caches. With caches, if you do multi-wipes of a file, in actuallity, you only do one real wipe & several virtual (to RAM) wipes. It might be possible to get around the first problem by using direct sector writes (INT 13 SERVICE 3) instead of well behaved (INT 21 SERVICE 40) writes. But this is a rather dangerous practice as if you make a mistake you might wreck the hard disk partition. Concerning the second, I see no practical way around the problem of hardware disk caches keeping the user from making multiple wipes of a file. As for making multiple wipes of CURRENTLY unused disk space, my SUPER- WIPE will do that with the options: /oldx /n . Where oldx points at the diskette drive or hard disk partition to be wiped & /n tells how many wipes to do (1-9). As for the problem of getting rid of old buffer data writes to the end of last file cluster writes, my program doesn't handle that. However, if there is no disk compressor, I don't think it would be that hard to write a function to handle it. In reality, I don't think that this problem is much of a problem anyway. It would only occur at the end of small files. I suspect that the wipe problems that we have with the DOS operating system are shared with most other operating systems. I uploaded SUPERWIPE to an anon ftp site. I believe it was Alex De Joode (or spelled something like that) who gave approval for the upload. It seems like it was a Utopia site. I lost my file on it and have now for- gotten. If anyone needs SUPERWIPE, send me a request. Some documentation follows for SUPERWIPE 1.04R: -------------Start of readme.spr file--------------------------------- SUPERWIPE current version: 1.04r SUPERWIPE is a utility that will substantially increase the security of your computer. What does SUPERWIPE do? In order to explain what it does, I first need to explain some security holes in the DOS operating system as it works with disks. The delete & erase DOS instructions are convenient utilities that allow you to get rid of old files. They don't actually destroy the files. They merely mark these files so that they will be ignored by the DOS operating system. Most of the time this is good enough. But what if you have sensi- tive files that must not be recovered? A snoop could use the popular DOS undelete command or another utility program to entirely recover these files. To solve this problem, wipe programs were invented. A wipe program will write a character, usually a 0 or a 1, over your entire file & then delete it. In this way, your sensitive files are made non-recoverable. NOTE: SUPERWIPE currently only works with non-compressed disks. SUPERWIPE also does this but with some improvements! SUPERWIPE (unregistered) will enable you to : 1. allow multiple files to be wiped instead of just one! 2. use wildcards! 3. mix your regular files with wildcards in any order you choose! Multiple wildcards may be interspersed with multiple regular files! 4. reduce your file to zero bytes, so that a snoop cannot determine with certainty what the original size was! 5. rename your file to a single letter, so that a snoop cannot determine what the original name was! 6. access several disk partitions (c: d: e: etc..) & diskette drives in one run! 7. starting with version 1.03, SUPERWIPE now has SUPER ERASE capabilities as well. All of the above capabilities are contained in this program. ADVANTAGES OF REGISTRATION FOLLOW: When you register, you will receive a registered version, that in addition to the above capabilities, will allow you to: 1: Wipe out all previously erased or deleted files! (The /OLD option.) The registered version will also have a nicer execution message that will lack the plea for money. You are probably wondering why you would want the capability to wipe out all previously deleted files. There are two reasons: one fairly ob- vious; one not. Firstly, those old deleted files may be sensitive & you forgot to wipe them properly. Or maybe, you were busy at an earlier time & did not take the time to properly wipe all the sensitive files. Or, you may not remem- ber wheather you wiped or erased a sensitive file. With the /OLD option, you can be sure that they are all wiped! Secondly, many programs, including some word processors, make temporary files that are used to assist that program in its work. When the program is done, those programs are deleted. Ordinarily, this is fine, but it does leave a security hole. The /OLD option will wipe out all of them! Note: Since the /OLD option must go through the entire "unused" disk par- tition or diskette, it may take several minutes to complete. 2. Registered users, will also be notified of improved versions of SUPERWIPE. 3. Upgrades, at least for the next upgrade, will only be $10. 4. Registered users will also receive telephone support. 5. Also, the registered user will have a clear conscience & will use SUPERWIPE with a feeling of sublime legitimacy! Site licenses are also available. -------------End of readme.spr file--------------------------------- -------------Start of .com help file------------------------------------ Gary's super file wipe/erase program. ver. 1.04r Copyright 1995 Gary Jeffers This ver. does not work with compressed disks. Nothing to do. Invocation syntax w filename1 filename2 ... wildcard1 wildcard2 ... /(no. of wipes for disk) /n(one alpha letter name of alternate file) /old{partition or drive letter} - (wipe all old deletes.-reg. only) /e for regular ERASE mode only - NO wipes. no parenthesis or braces in actual command line. The order of the tokens does not matter. examples: w my.fil new.fil /olda *.exe next????.com /5 /na w this.fil /e wild????.exe /nc anot????.com second.fil w that????.* /nk last.fil /oldc -------------End of .com help file------------------------------------ THE UNITED STATES "FEDERAL" GOVERNMENT HAS NO LEGITIMACY. The United States "Federal" Government - We'll be even more American without it. PUSH EM BACK! PUSH EM BACK! WWWAAAYYYY BBBAAACCCCK! BBBEEEAAATTTT STATE! Gary Jeffers