[PATCH v4 1/4] powerpc/powernv: Add OPAL API interface to access secure variable
Nayna Jain
nayna at linux.ibm.com
Wed Oct 2 09:41:48 AEST 2019
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 at linux.ibm.com>
Signed-off-by: Nayna Jain <nayna at linux.ibm.com>
---
arch/powerpc/include/asm/opal-api.h | 5 +-
arch/powerpc/include/asm/opal.h | 8 ++
arch/powerpc/include/asm/powernv.h | 2 +
arch/powerpc/include/asm/secvar.h | 35 +++++
arch/powerpc/kernel/Makefile | 2 +-
arch/powerpc/kernel/secvar-ops.c | 19 +++
arch/powerpc/platforms/powernv/Kconfig | 6 +
arch/powerpc/platforms/powernv/Makefile | 1 +
arch/powerpc/platforms/powernv/opal-call.c | 3 +
arch/powerpc/platforms/powernv/opal-secvar.c | 137 +++++++++++++++++++
arch/powerpc/platforms/powernv/opal.c | 5 +
11 files changed, 221 insertions(+), 2 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..03392dc3f5e2 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);
@@ -392,6 +399,7 @@ void opal_wake_poller(void);
void opal_powercap_init(void);
void opal_psr_init(void);
void opal_sensor_groups_init(void);
+void opal_secvar_init(void);
#endif /* __ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/powernv.h b/arch/powerpc/include/asm/powernv.h
index e1a858718716..cff980a85dd2 100644
--- a/arch/powerpc/include/asm/powernv.h
+++ b/arch/powerpc/include/asm/powernv.h
@@ -12,10 +12,12 @@ extern void powernv_set_nmmu_ptcr(unsigned long ptcr);
void pnv_program_cpu_hotplug_lpcr(unsigned int cpu, u64 lpcr_val);
void pnv_tm_init(void);
+
#else
static inline void powernv_set_nmmu_ptcr(unsigned long ptcr) { }
static inline void pnv_tm_init(void) { }
+
#endif
#endif /* _ASM_POWERNV_H */
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..4331a5b66ec0
--- /dev/null
+++ b/arch/powerpc/kernel/secvar-ops.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 IBM Corporation
+ * Author: Nayna Jain
+ *
+ * This file initializes secvar operations for PowerPC Secureboot
+ */
+
+#include <stddef.h>
+#include <asm/secvar.h>
+
+const struct secvar_operations *secvar_ops;
+
+void set_secvar_ops(const struct secvar_operations *ops)
+{
+ if (!ops)
+ secvar_ops = NULL;
+ secvar_ops = ops;
+}
diff --git a/arch/powerpc/platforms/powernv/Kconfig b/arch/powerpc/platforms/powernv/Kconfig
index 938803eab0ad..a1c7c8e2e683 100644
--- a/arch/powerpc/platforms/powernv/Kconfig
+++ b/arch/powerpc/platforms/powernv/Kconfig
@@ -50,3 +50,9 @@ config PPC_VAS
config SCOM_DEBUGFS
bool "Expose SCOM controllers via debugfs"
depends on DEBUG_FS
+
+config OPAL_SECVAR
+ bool "OPAL Secure Variables"
+ depends on PPC_POWERNV
+ help
+ This enables the kernel to access OPAL secure variables.
diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile
index a3ac9646119d..0ae688bde9b7 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -20,3 +20,4 @@ obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
obj-$(CONFIG_PPC_VAS) += vas.o vas-window.o vas-debug.o
obj-$(CONFIG_OCXL_BASE) += ocxl.o
obj-$(CONFIG_SCOM_DEBUGFS) += opal-xscom.o
+obj-$(CONFIG_OPAL_SECVAR) += opal-secvar.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..ad5c6b8019dd
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opal-secvar.c
@@ -0,0 +1,137 @@
+// 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 <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 bool is_opal_secvar_supported(void)
+{
+ static bool opal_secvar_supported;
+ static bool initialized;
+
+ if (initialized)
+ return opal_secvar_supported;
+
+ if (!is_powerpc_os_sb_supported()) {
+ opal_secvar_supported = false;
+ goto out;
+ }
+
+ 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");
+ opal_secvar_supported = false;
+ } else {
+ opal_secvar_supported = true;
+ }
+
+out:
+ initialized = true;
+
+ return opal_secvar_supported;
+}
+
+static int opal_get_variable(const char *key, uint64_t ksize,
+ u8 *data, uint64_t *dsize)
+{
+ int rc;
+
+ if (dsize)
+ *dsize = cpu_to_be64(*dsize);
+
+ rc = opal_secvar_get(key, ksize, data, dsize);
+
+ if (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 (keylen)
+ *keylen = cpu_to_be64(*keylen);
+
+ rc = opal_secvar_get_next(key, keylen, keybufsize);
+
+ if (keylen)
+ *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;
+
+ 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,
+};
+
+void opal_secvar_init(void)
+{
+ if (!is_opal_secvar_supported())
+ set_secvar_ops(NULL);
+
+ set_secvar_ops(&opal_secvar_ops);
+}
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index 38e90270280b..8e654d3735c1 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -32,6 +32,8 @@
#include <asm/mce.h>
#include <asm/imc-pmu.h>
#include <asm/bug.h>
+#include <asm/secvar.h>
+#include <asm/secure_boot.h>
#include "powernv.h"
@@ -1002,6 +1004,9 @@ static int __init opal_init(void)
/* Initialise OPAL Power control interface */
opal_power_control_init();
+ /* Initialize OPAL secure variables */
+ opal_secvar_init();
+
return 0;
}
machine_subsys_initcall(powernv, opal_init);
--
2.20.1
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