Re: [TOMOYO #15 0/8] TOMOYO Linux

Toshiharu Harada
2009-02-23T08:13:50Z

Pavel Machek wrote:
> On Sun 2009-02-22 23:27:34, Tetsuo Handa wrote:
>> Pavel Machek wrote:
>>> On Thu 2009-02-12 16:34:16, James Morris wrote:
>>>> On Thu, 5 Feb 2009, Kentaro Takeda wrote:
>>>>
>>>>> TOMOYO Linux is a name-based MAC extension (LSM module) for the Linux kernel.
>>>>>
>>>> Applied to
>>>> git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6#next
>>>>
>>> Does that mean tomoyo is scheduled for 2.6.30?
>>>
>> TOMOYO is already in linux-next tree and ready to go into 2.6.30 .
>
> Last time I looked it included script parser and some
> interpretter... Was that solved?
> Pavel

Are you talking about the interface between
userland and kernel regarding string data?

Linus once said in a Smack thread (http://lkml.org/lkml/2007/11/5/129)
>> On Sun, Nov 04, 2007 at 12:28:48PM +0000, Pavel Machek wrote:
>> > Can we avoid string parsers in the kernel?
>>
>> Ok, Could someone suggest a better idea please ?.
>
> I personally think string parsers are *much* better than the alternatives
> (which basically boil down to nasty binary interfaces)
>
>> I thought about packing the rules in a structure and sending
>> it over an ioctl() command. Is this applicable ?
>
> That's *MUCH* worse.
>
> Strings are nice. They aren't that complex, and as long as it's not a
> performance-critical area, there are basically no downsides.
>
> Binary structures and ioctl's are *much* worse. They are totally
> undebuggable with generic tools (think "echo" or "strace"), and they are a
> total nightmare to parse across architectures and pointer sizes.
>
> So the rule should be: always use strings if at all possible and relevant.
> If the data is fundamentally binary, it shouldn't be re-coded to ascii
> (no real advantage), but if the data is "stringish", and there aren't
> big performance issues, then keep it as strings.

Admiring your concern, I would like to follow the above directions.

Best regards,
Toshiharu Harada