Re: Revised keyrings(7) man page for review
From: Michael Kerrisk (man-pages)
Date: Tue Dec 13 2016 - 07:57:42 EST
Amended a piece here after Eugene's note about encrypted keys.
On 13 December 2016 at 13:43, Michael Kerrisk (man-pages)
> Hi David,
> On 12/13/2016 12:35 PM, David Howells wrote:
>> Michael Kerrisk <mtk@xxxxxxxx> wrote:
>>> "big_key" (since Linux 3.13)
>>> This key type is similar to the "user" key type, but it
>>> may hold a payload of up to 1MiB in size. The data may
>>> be stored in the swap space rather than in kernel memory
>> stored encrypted (as of 4.8).
> Added "encrypted".
So, I've updated this piece a couple of times since the draft that you
reviewed, and by now it reads:
"big_key" (since Linux 3.13)
This key type is similar to the "user" key type, but it may
hold a payload of up to 1 MiB in size. This key type is
useful for tasks such as holding Kerberos ticket caches.
The payload data may be stored in the swap space rather
than in kernel memory if the data size exceeds the overhead
of storing the data encrypted in swap space. (A tmpfs file
is used, which requires filesystem structures to be alloâ
cated in the kernel; The size of these structures deterâ
mines the size threshold above which the tmpfs storage
method is used.) Since Linux 4.8, payload data is
encrypted, to prevent it being written unencrypted into
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