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| author |   Nayna Jain <nayna@linux.ibm.com> | 2019-11-10 21:10:34 -0600 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2019-11-13 00:33:22 +1100 |
| commit | bd5d9c743d38f67d64ea1b512a461f6b5a5f6bec (patch) | |
| tree | ea45af52267b64c35dbc5d7eaf79fa108b1c82bc /Documentation | |
| parent | powerpc/powernv: Add OPAL API interface to access secure variable (diff) | |
| download | linux-dev-bd5d9c743d38f67d64ea1b512a461f6b5a5f6bec.tar.xz linux-dev-bd5d9c743d38f67d64ea1b512a461f6b5a5f6bec.zip | |
powerpc: expose secure variables to userspace via sysfs
PowerNV secure variables, which store the keys used for OS kernel
verification, are managed by the firmware. These secure variables need to
be accessed by the userspace for addition/deletion of the certificates.
This patch adds the sysfs interface to expose secure variables for PowerNV
secureboot. The users shall use this interface for manipulating
the keys stored in the secure variables.
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Eric Richter <erichte@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1573441836-3632-3-git-send-email-nayna@linux.ibm.com
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-secvar | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-secvar b/Documentation/ABI/testing/sysfs-secvar new file mode 100644 index 000000000000..feebb8c57294 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-secvar @@ -0,0 +1,46 @@ +What: /sys/firmware/secvar +Date: August 2019 +Contact: Nayna Jain <nayna@linux.ibm.com> +Description: This directory is created if the POWER firmware supports OS + secureboot, thereby secure variables. It exposes interface + for reading/writing the secure variables + +What: /sys/firmware/secvar/vars +Date: August 2019 +Contact: Nayna Jain <nayna@linux.ibm.com> +Description: This directory lists all the secure variables that are supported + by the firmware. + +What: /sys/firmware/secvar/format +Date: August 2019 +Contact: Nayna Jain <nayna@linux.ibm.com> +Description: A string indicating which backend is in use by the firmware. + This determines the format of the variable and the accepted + format of variable updates. + +What: /sys/firmware/secvar/vars/<variable name> +Date: August 2019 +Contact: Nayna Jain <nayna@linux.ibm.com> +Description: Each secure variable is represented as a directory named as + <variable_name>. The variable name is unique and is in ASCII + representation. The data and size can be determined by reading + their respective attribute files. + +What: /sys/firmware/secvar/vars/<variable_name>/size +Date: August 2019 +Contact: Nayna Jain <nayna@linux.ibm.com> +Description: An integer representation of the size of the content of the + variable. In other words, it represents the size of the data. + +What: /sys/firmware/secvar/vars/<variable_name>/data +Date: August 2019 +Contact: Nayna Jain h<nayna@linux.ibm.com> +Description: A read-only file containing the value of the variable. The size + of the file represents the maximum size of the variable data. + +What: /sys/firmware/secvar/vars/<variable_name>/update +Date: August 2019 +Contact: Nayna Jain <nayna@linux.ibm.com> +Description: A write-only file that is used to submit the new value for the + variable. The size of the file represents the maximum size of + the variable data that can be written. |