Re: Linux Security *Module* Framework (Was: LSM conversion to static interface)

Andrew Morgan
2007-11-05T06:56:20Z

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Peter Dolding wrote:
> On 11/1/07, Casey Schaufler <casey@schaufler-ca.com> wrote:
>> --- Peter Dolding <oiaohm@gmail.com> wrote:
>> Posix capabilities predate SELinux. SELinux is not interested in
>> Posix capabilities.
>>
>>> But no IBM had to do it.
>> Err, no. It was done by Andrew Morgan back in the dark ages.
>> Why on earth do you think IBM did it?
>
> Posix file capabilities the option to replace SUID bit with something
> more security safe only handing out segments of root power instead of
> the complete box and dice like SUID. Even different on a user by user
> base.
>
> Posix capabilites is what Posix file capabilities is based on. Yes I
> know the words appear close. The word file is important. Please read
> Website. http://www.ibm.com/developerworks/linux/library/l-posixcap.html

For the record, I think you are both right. I took a stab at it back
when Casey and I first met:

ftp://ftp.kernel.org/pub/linux/libs/security/linux-privs/old/kernel-2.4-fcap/README

all that stuff worked fine it was just a bit ahead of its time...

- From memory, at that point in time "extended attributes" were an
external patch, and having some trouble getting merged. My sense was
that EA was a pre-requisite and I was happy to wait for that support to
become integrated before pushing my file capability support.

In the midst of all this LSM emerged as a reaction to Linus' clear
unhappiness about all extensions security. I didn't have the time to
participate in the LSM, and my work sat in the form of these patches.

SELinux at that time existed as a separate infrastructure, and evidently
did have the time to embrace LSM.

> IBM coders worked and got it into the main line really recently to
> provide at least some way to avoid fault of SUID of course it could

[...]

So, yes, IBM (Serge) deserve full credit for starting over, and getting
it merged...

Cheers

Andrew
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