Read secure boot mode from 'ibm,secure-boot' property and if the secure boot
mode is set to 2 (enforce), enter lockdown. Else it is considered as disabled.
There are three secure boot modes. They are
0 - disabled
No signature verification is performed. This is the default.
1 - audit
Signature verification is performed and if signature verification fails,
display the errors and allow the boot to continue.
2 - enforce
Lockdown the GRUB. Signature verification is performed and if signature
verification fails, display the errors and stop the boot.
Now, only support disabled and enforce.
Signed-off-by: Daniel Axtens <[email protected]>
Signed-off-by: Sudhakar Kuppusamy <[email protected]>
Reviewed-by: Stefan Berger <[email protected]>
Reviewed-by: Avnish Chouhan <[email protected]>
Reviewed-by: Daniel Kiper <[email protected]>
---
docs/grub.texi | 2 +-
grub-core/Makefile.core.def | 1 +
grub-core/kern/ieee1275/init.c | 54 ++++++++++++++++++++++++++++++++++
include/grub/lockdown.h | 3 +-
4 files changed, 58 insertions(+), 2 deletions(-)
diff --git a/docs/grub.texi b/docs/grub.texi
index 37297fc2c..1c33b44e2 100644
--- a/docs/grub.texi
+++ b/docs/grub.texi
@@ -9144,7 +9144,7 @@ platforms.
@section Lockdown when booting on a secure setup
The GRUB can be locked down when booted on a secure boot environment, for
example
-if the UEFI secure boot is enabled. On a locked down configuration, the GRUB
will
+if UEFI or Power secure boot is enabled. On a locked down configuration, the
GRUB will
be restricted and some operations/commands cannot be executed. This also
includes
limiting which filesystems are supported to those thought to be more robust and
widely used within GRUB.
diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index 0fcf67f9d..8e3929710 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -333,6 +333,7 @@ kernel = {
powerpc_ieee1275 = kern/powerpc/cache.S;
powerpc_ieee1275 = kern/powerpc/dl.c;
powerpc_ieee1275 = kern/powerpc/compiler-rt.S;
+ powerpc_ieee1275 = kern/lockdown.c;
sparc64_ieee1275 = kern/sparc64/cache.S;
sparc64_ieee1275 = kern/sparc64/dl.c;
diff --git a/grub-core/kern/ieee1275/init.c b/grub-core/kern/ieee1275/init.c
index a5586f85b..28653a5a4 100644
--- a/grub-core/kern/ieee1275/init.c
+++ b/grub-core/kern/ieee1275/init.c
@@ -49,6 +49,14 @@
#if defined(__powerpc__) || defined(__i386__)
#include <grub/ieee1275/alloc.h>
#endif
+#if defined(__powerpc__)
+#include <grub/lockdown.h>
+#endif
+
+#ifdef __powerpc__
+#define GRUB_SB_DISABLED ((grub_uint32_t) 0)
+#define GRUB_SB_ENFORCE ((grub_uint32_t) 2)
+#endif
/* The maximum heap size we're going to claim at boot. Not used by sparc. */
#ifdef __i386__
@@ -994,7 +1002,49 @@ grub_parse_cmdline (void)
}
}
}
+#ifdef __powerpc__
+static void
+grub_ieee1275_get_secure_boot (void)
+{
+ grub_ieee1275_phandle_t root;
+ grub_uint32_t sb_mode = GRUB_SB_DISABLED;
+ grub_int32_t rc;
+
+ rc = grub_ieee1275_finddevice ("/", &root);
+ if (rc != 0)
+ {
+ grub_error (GRUB_ERR_UNKNOWN_DEVICE, "couldn't find / node");
+ return;
+ }
+ rc = grub_ieee1275_get_integer_property (root, "ibm,secure-boot", &sb_mode,
sizeof (sb_mode), 0);
+ if (rc != 0)
+ {
+ grub_error (GRUB_ERR_UNKNOWN_DEVICE, "couldn't examine /ibm,secure-boot
property");
+ return;
+ }
+ /*
+ * Secure Boot Mode:
+ * 0 - disabled
+ * No signature verification is performed. This is the default.
+ * 1 - audit
+ * Signature verification is performed and if signature verification
+ * fails, display the errors and allow the boot to continue.
+ * 2 - enforce
+ * Lockdown the GRUB. Signature verification is performed and If
+ * signature verification fails, display the errors and stop the boot.
+ *
+ * Now, only support disabled and enforce.
+ */
+ if (sb_mode == GRUB_SB_ENFORCE)
+ {
+ grub_dprintf ("ieee1275", "Secure Boot Enabled\n");
+ grub_lockdown ();
+ }
+ else
+ grub_dprintf ("ieee1275", "Secure Boot Disabled\n");
+}
+#endif /* __powerpc__ */
grub_addr_t grub_modbase;
void
@@ -1020,6 +1070,10 @@ grub_machine_init (void)
#else
grub_install_get_time_ms (grub_rtc_get_time_ms);
#endif
+
+#ifdef __powerpc__
+ grub_ieee1275_get_secure_boot ();
+#endif
}
void
diff --git a/include/grub/lockdown.h b/include/grub/lockdown.h
index 40531fa82..ebfee4bf0 100644
--- a/include/grub/lockdown.h
+++ b/include/grub/lockdown.h
@@ -24,7 +24,8 @@
#define GRUB_LOCKDOWN_DISABLED 0
#define GRUB_LOCKDOWN_ENABLED 1
-#ifdef GRUB_MACHINE_EFI
+#if defined(GRUB_MACHINE_EFI) || \
+ (defined(__powerpc__) && defined(GRUB_MACHINE_IEEE1275))
extern void
EXPORT_FUNC (grub_lockdown) (void);
extern int
--
2.50.1 (Apple Git-155)
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