Arch Linux

siv

Member

Registered: 2014-04-18

Posts: 25

[Solved] - Difference secure-delete and srm packages

Hi,
I was looking for a safe manner to delete files.

I found two packages on Arch's repositories:
- srm
- secure-delete (on AUR)

Which one I have to use? Trying to install both gave me a warning about conflict.

Maybe I have to use srm because it is updated recently?

Last edited by siv (2015-05-03 20:07:58)

karol

Archivist

Registered: 2009-05-06

Posts: 25,440

Re: [Solved] - Difference secure-delete and srm packages

The issue with the conflict is mentioned in the comments: https://aur.archlinux.org/packages/secure-delete/

You can try one first and then the other.

siv

Member

Registered: 2014-04-18

Posts: 25

Re: [Solved] - Difference secure-delete and srm packages

Hi,
thanks for the reply.

I saw:

There is a conflict with extra/srm - both packages contain /usr/bin/srm.

So both packages provide a binary called "srm" but comparing "man srm" and "man srm (of secure-delete package)" I saw that they are different.

Which one do you advice to use?

Thanks

tomk

Forum Fellow

From: Ireland

Registered: 2004-07-21

Posts: 9,839

Re: [Solved] - Difference secure-delete and srm packages

Try them both, decide for yourself.

siv

Member

Registered: 2014-04-18

Posts: 25

Re: [Solved] - Difference secure-delete and srm packages

Hi tomk,
I tried them both and both are simple to use and delete selected files.

But I don't have the "tools" to analyze which is more secure and effective deleting the files.

So I asked you.

Spider.007

Member

Registered: 2004-06-20

Posts: 1,175

Re: [Solved] - Difference secure-delete and srm packages

I'm not sure any of them are significantly better then 'shred', which is in coreutils

siv

Member

Registered: 2014-04-18

Posts: 25

Re: [Solved] - Difference secure-delete and srm packages

Hi Spider.007, thank you for your reply.
You are right.

I'm interested in secure-delete because this suite had other tools like sfill, but like you said I can:
- Use shred for single file
- Simulate sfill with:

dd if=/dev/zero of=freespace; sync; rm freespace; sync

Spider.007

Member

Registered: 2004-06-20

Posts: 1,175

Re: [Solved] - Difference secure-delete and srm packages

If you're not sure how to analyze the results I'd use existing tools instead of hand-written scripts, you have a bigger chance of them doing what they should. If you need to securely erase free-space I'd use sfill from any of those packages, shred should to fine for any other files you want to have deleted after that!

siv

Member

Registered: 2014-04-18

Posts: 25

Re: [Solved] - Difference secure-delete and srm packages

Thank you for the advice to use shred and the secure-delete suit (that include sfill).

However the command that erase the free space with dd should be ok, it's mentionated on several forums/threads.

Spider.007

Member

Registered: 2004-06-20

Posts: 1,175

Re: [Solved] - Difference secure-delete and srm packages

No its not; the biggest problem is that you only overwrite with zeros, not random data (which shred does correctly for files, and I assume sfill does for empty space). There are additional problems with this approach which is why, if you need security; you should leave that to people who know what they are doing.

nofi; you probably have no serious need for secure wipe anyway and maybe dd is good enough for you

siv

Member

Registered: 2014-04-18

Posts: 25

Re: [Solved] - Difference secure-delete and srm packages

Yeah, you're right, I have no extremely sensitive data but only just personal files.

As you said the best option is first of all leave security to people who know and then use random data instead of zeroes.

But, correct me if I'm wrong, I read that in theory fill with random data is the best choice but practically use zeroes is just enough in most cases.

Spider.007

Member

Registered: 2004-06-20

Posts: 1,175

Re: [Solved] - Difference secure-delete and srm packages

Yes, I agree