The X.509 certificates trusted by the platform and required to secure boot
the OS kernel are wrapped in secure variables, which are controlled by
OPAL.
This patch adds firmware/kernel interface to read and write OPAL secure
variables based on the unique key.
This support can be enabled using CONFIG_OPAL_SECVAR.
Signed-off-by: Claudio Carvalho <cclaudio@xxxxxxxxxxxxx>
Signed-off-by: Nayna Jain <nayna@xxxxxxxxxxxxx>
Signed-off-by: Eric Richter <erichte@xxxxxxxxxxxxx>
---
arch/powerpc/include/asm/opal-api.h | 5 +-
arch/powerpc/include/asm/opal.h | 7 ++
arch/powerpc/include/asm/secvar.h | 35 +++++++
arch/powerpc/kernel/Makefile | 2 +-
arch/powerpc/kernel/secvar-ops.c | 16 +++
arch/powerpc/platforms/powernv/Makefile | 2 +-
arch/powerpc/platforms/powernv/opal-call.c | 3 +
arch/powerpc/platforms/powernv/opal-secvar.c | 140 +++++++++++++++++++++++++++
arch/powerpc/platforms/powernv/opal.c | 3 +
9 files changed, 210 insertions(+), 3 deletions(-)
create mode 100644 arch/powerpc/include/asm/secvar.h
create mode 100644 arch/powerpc/kernel/secvar-ops.c
create mode 100644 arch/powerpc/platforms/powernv/opal-secvar.c
diff --git a/arch/powerpc/include/asm/opal-api.h b/arch/powerpc/include/asm/opal-api.h
index 378e3997845a..c1f25a760eb1 100644
--- a/arch/powerpc/include/asm/opal-api.h
+++ b/arch/powerpc/include/asm/opal-api.h
@@ -211,7 +211,10 @@
#define OPAL_MPIPL_UPDATE 173
#define OPAL_MPIPL_REGISTER_TAG 174
#define OPAL_MPIPL_QUERY_TAG 175
-#define OPAL_LAST 175
+#define OPAL_SECVAR_GET 176
+#define OPAL_SECVAR_GET_NEXT 177
+#define OPAL_SECVAR_ENQUEUE_UPDATE 178
+#define OPAL_LAST 178
#define QUIESCE_HOLD 1 /* Spin all calls at entry */
#define QUIESCE_REJECT 2 /* Fail all calls with OPAL_BUSY */
diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
index a0cf8fba4d12..9986ac34b8e2 100644
--- a/arch/powerpc/include/asm/opal.h
+++ b/arch/powerpc/include/asm/opal.h
@@ -298,6 +298,13 @@ int opal_sensor_group_clear(u32 group_hndl, int token);
int opal_sensor_group_enable(u32 group_hndl, int token, bool enable);
int opal_nx_coproc_init(uint32_t chip_id, uint32_t ct);
+int opal_secvar_get(const char *key, uint64_t key_len, u8 *data,
+ uint64_t *data_size);
+int opal_secvar_get_next(const char *key, uint64_t *key_len,
+ uint64_t key_buf_size);
+int opal_secvar_enqueue_update(const char *key, uint64_t key_len, u8 *data,
+ uint64_t data_size);
+
s64 opal_mpipl_update(enum opal_mpipl_ops op, u64 src, u64 dest, u64 size);
s64 opal_mpipl_register_tag(enum opal_mpipl_tags tag, u64 addr);
s64 opal_mpipl_query_tag(enum opal_mpipl_tags tag, u64 *addr);
diff --git a/arch/powerpc/include/asm/secvar.h b/arch/powerpc/include/asm/secvar.h
new file mode 100644
index 000000000000..4cc35b58b986
--- /dev/null
+++ b/arch/powerpc/include/asm/secvar.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 IBM Corporation
+ * Author: Nayna Jain
+ *
+ * PowerPC secure variable operations.
+ */
+#ifndef SECVAR_OPS_H
+#define SECVAR_OPS_H
+
+#include <linux/types.h>
+#include <linux/errno.h>
+
+extern const struct secvar_operations *secvar_ops;
+
+struct secvar_operations {
+ int (*get)(const char *key, uint64_t key_len, u8 *data,
+ uint64_t *data_size);
+ int (*get_next)(const char *key, uint64_t *key_len,
+ uint64_t keybufsize);
+ int (*set)(const char *key, uint64_t key_len, u8 *data,
+ uint64_t data_size);
+};
+
+#ifdef CONFIG_PPC_SECURE_BOOT
+
+extern void set_secvar_ops(const struct secvar_operations *ops);
+
+#else
+
+static inline void set_secvar_ops(const struct secvar_operations *ops) { }
+
+#endif
+
+#endif
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index e8eb2955b7d5..3cf26427334f 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -161,7 +161,7 @@ ifneq ($(CONFIG_PPC_POWERNV)$(CONFIG_PPC_SVM),)
obj-y += ucall.o
endif
-obj-$(CONFIG_PPC_SECURE_BOOT) += secure_boot.o ima_arch.o
+obj-$(CONFIG_PPC_SECURE_BOOT) += secure_boot.o ima_arch.o secvar-ops.o
# Disable GCOV, KCOV & sanitizers in odd or sensitive code
GCOV_PROFILE_prom_init.o := n
diff --git a/arch/powerpc/kernel/secvar-ops.c b/arch/powerpc/kernel/secvar-ops.c
new file mode 100644
index 000000000000..4cfa7dbd8850
--- /dev/null
+++ b/arch/powerpc/kernel/secvar-ops.c
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 IBM Corporation
+ * Author: Nayna Jain
+ *
+ * This file initializes secvar operations for PowerPC Secureboot
+ */
+
+#include <asm/secvar.h>
+
+const struct secvar_operations *secvar_ops;
+
+void set_secvar_ops(const struct secvar_operations *ops)
+{
+ secvar_ops = ops;
+}
diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile
index a3ac9646119d..f9c4fa99e8b9 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -4,7 +4,7 @@ obj-y += idle.o opal-rtc.o opal-nvram.o opal-lpc.o opal-flash.o
obj-y += rng.o opal-elog.o opal-dump.o opal-sysparam.o opal-sensor.o
obj-y += opal-msglog.o opal-hmi.o opal-power.o opal-irqchip.o
obj-y += opal-kmsg.o opal-powercap.o opal-psr.o opal-sensor-groups.o
-obj-y += ultravisor.o
+obj-y += ultravisor.o opal-secvar.o
obj-$(CONFIG_SMP) += smp.o subcore.o subcore-asm.o
obj-$(CONFIG_FA_DUMP) += opal-fadump.o
diff --git a/arch/powerpc/platforms/powernv/opal-call.c b/arch/powerpc/platforms/powernv/opal-call.c
index a2aa5e433ac8..5cd0f52d258f 100644
--- a/arch/powerpc/platforms/powernv/opal-call.c
+++ b/arch/powerpc/platforms/powernv/opal-call.c
@@ -290,3 +290,6 @@ OPAL_CALL(opal_nx_coproc_init, OPAL_NX_COPROC_INIT);
OPAL_CALL(opal_mpipl_update, OPAL_MPIPL_UPDATE);
OPAL_CALL(opal_mpipl_register_tag, OPAL_MPIPL_REGISTER_TAG);
OPAL_CALL(opal_mpipl_query_tag, OPAL_MPIPL_QUERY_TAG);
+OPAL_CALL(opal_secvar_get, OPAL_SECVAR_GET);
+OPAL_CALL(opal_secvar_get_next, OPAL_SECVAR_GET_NEXT);
+OPAL_CALL(opal_secvar_enqueue_update, OPAL_SECVAR_ENQUEUE_UPDATE);
diff --git a/arch/powerpc/platforms/powernv/opal-secvar.c b/arch/powerpc/platforms/powernv/opal-secvar.c
new file mode 100644
index 000000000000..14133e120bdd
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opal-secvar.c
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PowerNV code for secure variables
+ *
+ * Copyright (C) 2019 IBM Corporation
+ * Author: Claudio Carvalho
+ * Nayna Jain
+ *
+ * APIs to access secure variables managed by OPAL.
+ */
+
+#define pr_fmt(fmt) "secvar: "fmt
+
+#include <linux/types.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+#include <asm/opal.h>
+#include <asm/secvar.h>
+#include <asm/secure_boot.h>
+
+static int opal_status_to_err(int rc)
+{
+ int err;
+
+ switch (rc) {
+ case OPAL_SUCCESS:
+ err = 0;
+ break;
+ case OPAL_UNSUPPORTED:
+ err = -ENXIO;
+ break;
+ case OPAL_PARAMETER:
+ err = -EINVAL;
+ break;
+ case OPAL_RESOURCE:
+ err = -ENOSPC;
+ break;
+ case OPAL_HARDWARE:
+ err = -EIO;
+ break;
+ case OPAL_NO_MEM:
+ err = -ENOMEM;
+ break;
+ case OPAL_EMPTY:
+ err = -ENOENT;
+ break;
+ case OPAL_PARTIAL:
+ err = -EFBIG;
+ break;
+ default:
+ err = -EINVAL;
+ }
+
+ return err;
+}
+
+static int opal_get_variable(const char *key, uint64_t ksize,
+ u8 *data, uint64_t *dsize)
+{
+ int rc;
+
+ if (!key || !dsize)
+ return -EINVAL;
+
+ *dsize = cpu_to_be64(*dsize);
+
+ rc = opal_secvar_get(key, ksize, data, dsize);
+
+ *dsize = be64_to_cpu(*dsize);
+
+ return opal_status_to_err(rc);
+}
+
+static int opal_get_next_variable(const char *key, uint64_t *keylen,
+ uint64_t keybufsize)
+{
+ int rc;
+
+ if (!key || !keylen)
+ return -EINVAL;
+
+ *keylen = cpu_to_be64(*keylen);
+
+ rc = opal_secvar_get_next(key, keylen, keybufsize);
+
+ *keylen = be64_to_cpu(*keylen);
+
+ return opal_status_to_err(rc);
+}
+
+static int opal_set_variable(const char *key, uint64_t ksize, u8 *data,
+ uint64_t dsize)
+{
+ int rc;
+
+ if (!key || !data)
+ return -EINVAL;
+
+ rc = opal_secvar_enqueue_update(key, ksize, data, dsize);
+
+ return opal_status_to_err(rc);
+}
+
+static const struct secvar_operations opal_secvar_ops = {
+ .get = opal_get_variable,
+ .get_next = opal_get_next_variable,
+ .set = opal_set_variable,
+};
+
+static int opal_secvar_probe(struct platform_device *pdev)
+{
+ if (!opal_check_token(OPAL_SECVAR_GET)
+ || !opal_check_token(OPAL_SECVAR_GET_NEXT)
+ || !opal_check_token(OPAL_SECVAR_ENQUEUE_UPDATE)) {
+ pr_err("OPAL doesn't support secure variables\n");
+ return -ENODEV;
+ }
+
+ set_secvar_ops(&opal_secvar_ops);
+
+ return 0;
+}
+
+static const struct of_device_id opal_secvar_match[] = {
+ { .compatible = "ibm,secvar-backend",},
+ {},
+};
+
+static struct platform_driver opal_secvar_driver = {
+ .driver = {
+ .name = "secvar",
+ .of_match_table = opal_secvar_match,
+ },
+};
+
+static int __init opal_secvar_init(void)
+{
+ return platform_driver_probe(&opal_secvar_driver, opal_secvar_probe);
+}
+device_initcall(opal_secvar_init);
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index 38e90270280b..8355bcd00f93 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -1002,6 +1002,9 @@ static int __init opal_init(void)
/* Initialise OPAL Power control interface */
opal_power_control_init();
+ /* Initialize OPAL secure variables */
+ opal_pdev_init("ibm,secvar-backend");
+
return 0;
}
machine_subsys_initcall(powernv, opal_init);
--
2.13.6
