From supernaut at underwares.org Wed May 2 11:11:04 2007 From: supernaut at underwares.org (Alexandre Gauthier) Date: Wed May 2 11:11:40 2007 Subject: [X-Unix] Any Command-Line Tools for Secure Delete or File Wipe ??? In-Reply-To: <8199E4E1-AC95-4E27-A974-3DBFFEC5B105@mr.au.dk> References: <8199E4E1-AC95-4E27-A974-3DBFFEC5B105@mr.au.dk> Message-ID: <4638D438.5070601@underwares.org> Steffen Hokland a ?crit : > Hi Rick > > On May 1, 2007, at 8:04 AM, Rick Gordon wrote: > >> Is there any way to effect a secure delete or file wipe -- zeroing >> out the original data -- from the command line? > Check out > > srm > > HTH, > Steffen I thought that secure delete utilities re-writing slack space and overwriting the files to oblivion where rendered useless on Journaling file systems such as HFS+, ReiserFS and ext3? > > > ___________________________________________ > Steffen Lund Hokland, MSc. > PhD Student > > The MR-Research Centre > Institute of Clinical Medicine > Aarhus University Hospital > Skejby Hospital > DK-8200 Aarhus > Denmark > > AND > > Department of Experimental Clinical Oncology > Aarhus University Hospital > Aarhus Hospital Noerrebrogade > DK-8000 Aarhus C > > Phone Office MR-C : +45 89495264 > Phone Office DECO : +45 89492620 > Phone Home : +45 48414828 > Phone Mobile : +45 61307461 > > e-mail : hokland@mr.au.dk > ___________________________________________ > > > > _______________________________________________ > X-Unix mailing list > X-Unix@listserver.themacintoshguy.com > http://listserver.themacintoshguy.com/mailman/listinfo/x-unix > > Listmom is trying to clean out his closets! Vintage Mac and random stuff: > http://search.ebay.com/_W0QQsassZmacguy1984 From subscriber at gloaming.com Wed May 2 12:17:33 2007 From: subscriber at gloaming.com (James Bucanek) Date: Wed May 2 12:17:44 2007 Subject: [X-Unix] Any Command-Line Tools for Secure Delete or File Wipe ??? In-Reply-To: <4638D438.5070601@underwares.org> Message-ID: Alexandre Gauthier wrote on Wednesday, May 2, 2007: >I thought that secure delete utilities re-writing slack space and >overwriting the files to oblivion where rendered useless on Journaling >file systems such as HFS+, ReiserFS and ext3? I can't speak to ReiserFS or ext3, but HFS+ journaling does not journal data. It only caches transient structural changes to the directory and volume maps. Besides, no FS can save the data forever. If you delete the file and overwrite all of the free space, where could the data be? The file system can't hide it between the tracks. -- James Bucanek From macmonster at myrealbox.com Wed May 2 14:51:05 2007 From: macmonster at myrealbox.com (Stroller) Date: Wed May 2 14:51:27 2007 Subject: [X-Unix] Any Command-Line Tools for Secure Delete or File Wipe ??? In-Reply-To: <4638D438.5070601@underwares.org> References: <8199E4E1-AC95-4E27-A974-3DBFFEC5B105@mr.au.dk> <4638D438.5070601@underwares.org> Message-ID: <47337094-8715-4246-982F-1BE5C6AA2BC4@myrealbox.com> On 2 May 2007, at 19:11, Alexandre Gauthier wrote: >>> ... >>> Is there any way to effect a secure delete or file wipe -- >>> zeroing out the original data -- from the command line? >> Check out >> >> srm > > that secure delete utilities re-writing slack space and > overwriting the files to oblivion where rendered useless on > Journaling file systems such as HFS+, ReiserFS and ext3? My understanding was that data on ReiserFS can't be shredded because a file doesn't remain in the same place when it's rewritten. IE: if you `touch foo bar && cp bar foo` then the contents of bar are written into a new file during the copying process - the reference to the original foo is then removed & the filename foo linked to the new (copy of bar) file. Likewise, if you edit foo & resave it (on a ReiserFS FS) the original data contents may be left somewhere in the disk's "empty space" (once the reference to it has been removed from the file allocation table or whatever), which is hence why `shred` doesn't work on ReiserFS. My understanding is that this is a side-effect of ReiserFS' clever "B- tree" storage algorithm. My understanding is that `shred` _does_ work on ext3 because ext3 writes in place, but I have to admit I have never considered the implications of the journal in this regard. Wouldn't the journal simply reflect the zeros (or whatever) written over the file, upon completion of the write? Stroller. From macdaddee at gmail.com Fri May 18 13:07:02 2007 From: macdaddee at gmail.com (Mac Daddy) Date: Fri May 18 13:07:15 2007 Subject: [X-Unix] Parallels Dammit! Anyone here running Linux under it? Message-ID: <061B6035-8B45-4A6A-968D-92CE95BFEE82@gmail.com> Unlike most people, I'm running FC6 under Parallels on my Mac, not Windows. I figured I'd be more likely find similar users on the Unix side of the Mac lists. I hope so. I'm having an ANNOYING problem where my system clock in the Parallels environment continuously gains time as the day goes on. If I reset it with a hwclock command, within a few minutes it's as much as 5 minutes fast, and within about 30 it's an hour ahead. And everything's all shot to HELL if I put my Mac to sleep and wake it back up. Time's just all over the place. The more I google it the more I am convinced this is a hardware problem, not a Fedora problem, the "hardware" here being the Parallels VM. The time and zone of the greater Mac outside is always correct. This is a problem because I need to immerse myself in the Linux environment at work and send e-mail from within there ... frequently time-stamped in the future, sometimes the past (after sleeping my Mac)! Grrrrr! Has anyone encountered this? And hopefully resolved it? -md From wingedpower at gmail.com Fri May 18 13:43:04 2007 From: wingedpower at gmail.com (Wing Wong) Date: Fri May 18 13:43:14 2007 Subject: [X-Unix] Parallels Dammit! Anyone here running Linux under it? In-Reply-To: <061B6035-8B45-4A6A-968D-92CE95BFEE82@gmail.com> References: <061B6035-8B45-4A6A-968D-92CE95BFEE82@gmail.com> Message-ID: <7097bd8c0705181343y519407apfe068555f7409cf4@mail.gmail.com> Hi MD, The problem, I think, has something to do with how certain CPU(s) and OS(s) deal with idle/sleep states, internal to the OS. Time drift is an issue which plagues virtual machines. I've heard of some suggesting the following in your grub configuration (/boot/grub/menu.lst): title SOME INSTANCE OF LINUX UNDER GRUB root (hd0,0) kernel /vmlinuz-some-revision ro root=/dev/some-root-device quiet acpi=off noapic nolapic Note the "acpi=off noapic nolapic" options. Those disable certain sleep/power management features as well as timing features for the Linux OS. Give those a try and see if it doesn't help with the time issues. Good Luck! Wing. On 5/18/07, Mac Daddy wrote: > Unlike most people, I'm running FC6 under Parallels on my Mac, not > Windows. I figured I'd be more likely find similar users on the Unix > side of the Mac lists. I hope so. > > I'm having an ANNOYING problem where my system clock in the Parallels > environment continuously gains time as the day goes on. If I reset it > with a hwclock command, within a few minutes it's as much as 5 > minutes fast, and within about 30 it's an hour ahead. And > everything's all shot to HELL if I put my Mac to sleep and wake it > back up. Time's just all over the place. > > The more I google it the more I am convinced this is a hardware > problem, not a Fedora problem, the "hardware" here being the > Parallels VM. The time and zone of the greater Mac outside is always > correct. This is a problem because I need to immerse myself in the > Linux environment at work and send e-mail from within there ... > frequently time-stamped in the future, sometimes the past (after > sleeping my Mac)! Grrrrr! > > Has anyone encountered this? And hopefully resolved it? > > -md > _______________________________________________ > X-Unix mailing list > X-Unix@listserver.themacintoshguy.com > http://listserver.themacintoshguy.com/mailman/listinfo/x-unix > > Listmom is trying to clean out his closets! Vintage Mac and random stuff: > http://search.ebay.com/_W0QQsassZmacguy1984 > -- Wing Wong wingedpower@gmail.com