linux/arch/powerpc/kernel/secure_boot.c
Nayna Jain 61f879d97c powerpc/pseries: Detect secure and trusted boot state of the system.
The device-tree properties to check secure and trusted boot state are
different for guests (pseries) compared to baremetal (powernv).

This patch updates the existing is_ppc_secureboot_enabled() and
is_ppc_trustedboot_enabled() functions to add support for pseries.

For pseries the secureboot and trustedboot state are exposed via
device-tree properties /ibm,secure-boot and /ibm,trusted-boot.

The values of ibm,secure-boot under pseries are interpreted as:

  0   - Disabled
  1   - Enabled in Log-only mode. This patch interprets this value as
        disabled, since audit mode is currently not supported for
	Linux.
  2   - Enabled and enforced.
  3-9 - Enabled and enforcing; requirements are at the discretion of
        the operating system.

The values of ibm,trusted-boot under pseries are interpreted as:
  0 - Disabled
  1 - Enabled

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
[mpe: Drop machdep.h inclusion, tweak change log slightly]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1594813921-12425-1-git-send-email-nayna@linux.ibm.com
2020-07-16 14:49:53 +10:00

65 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2019 IBM Corporation
* Author: Nayna Jain
*/
#include <linux/types.h>
#include <linux/of.h>
#include <asm/secure_boot.h>
static struct device_node *get_ppc_fw_sb_node(void)
{
static const struct of_device_id ids[] = {
{ .compatible = "ibm,secureboot", },
{ .compatible = "ibm,secureboot-v1", },
{ .compatible = "ibm,secureboot-v2", },
{},
};
return of_find_matching_node(NULL, ids);
}
bool is_ppc_secureboot_enabled(void)
{
struct device_node *node;
bool enabled = false;
u32 secureboot;
node = get_ppc_fw_sb_node();
enabled = of_property_read_bool(node, "os-secureboot-enforcing");
of_node_put(node);
if (enabled)
goto out;
if (!of_property_read_u32(of_root, "ibm,secure-boot", &secureboot))
enabled = (secureboot > 1);
out:
pr_info("Secure boot mode %s\n", enabled ? "enabled" : "disabled");
return enabled;
}
bool is_ppc_trustedboot_enabled(void)
{
struct device_node *node;
bool enabled = false;
u32 trustedboot;
node = get_ppc_fw_sb_node();
enabled = of_property_read_bool(node, "trusted-enabled");
of_node_put(node);
if (enabled)
goto out;
if (!of_property_read_u32(of_root, "ibm,trusted-boot", &trustedboot))
enabled = (trustedboot > 0);
out:
pr_info("Trusted boot mode %s\n", enabled ? "enabled" : "disabled");
return enabled;
}