8cf57d7217
Enable receiving the user-defined certificates from the s390x
hypervisor via new diagnose 0x320 calls, and make them available to the
Linux root user as 'cert_store_key' type keys in a so-called
'cert_store' keyring.
New user-space interfaces:
/sys/firmware/cert_store/refresh
Writing to this attribute re-fetches certificates via DIAG 0x320
/sys/firmware/cert_store/cs_status
Reading from this attribute returns either of:
"uninitialized"
If no certificate has been retrieved yet
"ok"
If certificates have been successfully retrieved
"failed (<number>)"
If certificate retrieval failed with reason code <number>
New debug trace areas:
/sys/kernel/debug/s390dbf/cert_store_msg
/sys/kernel/debug/s390dbf/cert_store_hexdump
Usage example:
To initiate request for certificates available to the system as root:
$ echo 1 > /sys/firmware/cert_store/refresh
Upon success the '/sys/firmware/cert_store/cs_status' contains
the value 'ok'.
$ cat /sys/firmware/cert_store/cs_status
ok
Get the ID of the keyring 'cert_store':
$ keyctl search @us keyring cert_store
OR
$ keyctl link @us @s; keyctl request keyring cert_store
Obtain list of IDs of certificates:
$ keyctl rlist <cert_store keyring ID>
Display certificate content as hex-dump:
$ keyctl read <certificate ID>
Read certificate contents as binary data:
$ keyctl pipe <certificate ID> >cert_data
Display certificate description:
$ keyctl describe <certificate ID>
The certificate description has the following format:
<64 bytes certificate name in EBCDIC> ':'
<certificate index as obtained from hypervisor> ':'
<certificate store token obtained from hypervisor>
The certificate description in /proc/keys has certificate name
represented in ASCII.
Users can read but cannot update the content of the certificate.
Signed-off-by: Anastasia Eskova <anastasia.eskova@ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.