feat(cros_widevine): add ChromeOS widevine SMC handler
The ChromeOS will use the SMC to pass some secrets from firmware to
optee.
Change-Id: Iaf3357d40a7ed22415926acd9d7979df24dd81f1
Signed-off-by: Yi Chou <yich@google.com>
diff --git a/bl31/bl31.mk b/bl31/bl31.mk
index 40e3df8..9959a3e 100644
--- a/bl31/bl31.mk
+++ b/bl31/bl31.mk
@@ -161,6 +161,10 @@
${MBEDTLS_SOURCES}
endif
+ifeq ($(CROS_WIDEVINE_SMC),1)
+BL31_SOURCES += services/oem/chromeos/widevine_smc_handlers.c
+endif
+
BL31_DEFAULT_LINKER_SCRIPT_SOURCE := bl31/bl31.ld.S
ifneq ($(findstring gcc,$(notdir $(LD))),)
diff --git a/include/services/oem/chromeos/widevine_smc_handlers.h b/include/services/oem/chromeos/widevine_smc_handlers.h
new file mode 100644
index 0000000..a5251d7
--- /dev/null
+++ b/include/services/oem/chromeos/widevine_smc_handlers.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2024, The ChromiumOS Authors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef CROS_WIDEVINE_SMC_HANDLERS_H
+#define CROS_WIDEVINE_SMC_HANDLERS_H
+
+#include <lib/smccc.h>
+
+/*******************************************************************************
+ * Defines for CrOS OEM Service queries
+ ******************************************************************************/
+
+/* 0xC300C050 - 0xC300C05F are CrOS OEM service calls */
+#define CROS_OEM_SMC_ID 0xC050
+#define CROS_OEM_SMC_CALL_ID(func_num) \
+ ((SMC_TYPE_FAST << FUNCID_TYPE_SHIFT) | \
+ ((SMC_64) << FUNCID_CC_SHIFT) | (OEN_OEM_START << FUNCID_OEN_SHIFT) | \
+ (CROS_OEM_SMC_ID) | ((func_num) & FUNCID_NUM_MASK))
+
+enum cros_drm_set {
+ CROS_DRM_SET_TPM_AUTH_PUB = 0U,
+ CROS_DRM_SET_HARDWARE_UNIQUE_KEY = 1U,
+ CROS_DRM_SET_ROOT_OF_TRUST = 2U,
+};
+
+/*******************************************************************************
+ * Defines for runtime services func ids
+ ******************************************************************************/
+
+/* Sets the TPM auth public key. The maximum size is 128 bytes.
+ * |x1| is the length of the data, |x2| is the physical address of the data.
+ */
+#define CROS_OEM_SMC_DRM_SET_TPM_AUTH_PUB_FUNC_ID \
+ CROS_OEM_SMC_CALL_ID(CROS_DRM_SET_TPM_AUTH_PUB)
+
+/* Sets the hardware unique key. The maximum size is 32 bytes.
+ * |x1| is the length of the data, |x2| is the physical address of the data.
+ */
+#define CROS_OEM_SMC_DRM_SET_HARDWARE_UNIQUE_KEY_FUNC_ID \
+ CROS_OEM_SMC_CALL_ID(CROS_DRM_SET_HARDWARE_UNIQUE_KEY)
+
+/* Sets the widevine root of trust. The maximum size is 32 bytes.
+ * |x1| is the length of the data, |x2| is the physical address of the data.
+ */
+#define CROS_OEM_SMC_DRM_SET_ROOT_OF_TRUST_FUNC_ID \
+ CROS_OEM_SMC_CALL_ID(CROS_DRM_SET_ROOT_OF_TRUST)
+
+#define is_cros_oem_smc(_call_id) (((_call_id) & 0xFFF0U) == CROS_OEM_SMC_ID)
+
+struct cros_oem_data {
+ uint8_t *buffer;
+ const uint32_t max_length;
+ uint32_t length;
+};
+
+extern struct cros_oem_data cros_oem_tpm_auth_pk;
+
+extern struct cros_oem_data cros_oem_huk;
+
+extern struct cros_oem_data cros_oem_rot;
+
+#endif /* CROS_WIDEVINE_SMC_HANDLERS_H */
diff --git a/services/oem/chromeos/widevine_smc_handlers.c b/services/oem/chromeos/widevine_smc_handlers.c
new file mode 100644
index 0000000..83c6ccc
--- /dev/null
+++ b/services/oem/chromeos/widevine_smc_handlers.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2024, The ChromiumOS Authors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <stdint.h>
+#include <string.h>
+
+#include <common/debug.h>
+#include <common/runtime_svc.h>
+#include <lib/psci/psci.h>
+#include <lib/xlat_tables/xlat_tables_v2.h>
+#include <services/oem/chromeos/widevine_smc_handlers.h>
+#include <tools_share/uuid.h>
+
+#define CROS_OEM_TPM_AUTH_PK_MAX_LEN 128
+#define CROS_OEM_HUK_LEN 32
+#define CROS_OEM_ROT_LEN 32
+
+static uint8_t cros_oem_tpm_auth_pk_buffer[CROS_OEM_TPM_AUTH_PK_MAX_LEN];
+static uint8_t cros_oem_huk_buffer[CROS_OEM_HUK_LEN];
+static uint8_t cros_oem_rot_len_buffer[CROS_OEM_ROT_LEN];
+
+struct cros_oem_data cros_oem_tpm_auth_pk = {
+ .buffer = cros_oem_tpm_auth_pk_buffer,
+ .max_length = sizeof(cros_oem_tpm_auth_pk_buffer),
+};
+
+struct cros_oem_data cros_oem_huk = {
+ .buffer = cros_oem_huk_buffer,
+ .max_length = sizeof(cros_oem_huk_buffer),
+};
+
+struct cros_oem_data cros_oem_rot = {
+ .buffer = cros_oem_rot_len_buffer,
+ .max_length = sizeof(cros_oem_rot_len_buffer),
+};
+
+static uintptr_t cros_write_data(struct cros_oem_data *data,
+ u_register_t length, u_register_t address,
+ void *handle)
+{
+ uintptr_t aligned_address;
+ uintptr_t aligned_size;
+ int32_t rc;
+
+ if (data->length) {
+ SMC_RET1(handle, PSCI_E_ALREADY_ON);
+ }
+
+ if (length > data->max_length) {
+ SMC_RET1(handle, PSCI_E_INVALID_PARAMS);
+ }
+
+ aligned_address = page_align(address, DOWN);
+ aligned_size = page_align(length + (address - aligned_address), UP);
+
+ /*
+ * We do not validate the passed in address because we are trusting the
+ * non-secure world at this point still.
+ */
+ rc = mmap_add_dynamic_region(aligned_address, aligned_address,
+ aligned_size, MT_MEMORY | MT_RO | MT_NS);
+ if (rc != 0) {
+ SMC_RET1(handle, PSCI_E_INVALID_ADDRESS);
+ }
+
+ memcpy(data->buffer, (void *)address, length);
+ data->length = length;
+
+ mmap_remove_dynamic_region(aligned_address, aligned_size);
+ SMC_RET1(handle, SMC_OK);
+}
+
+/* Handler for servicing specific SMC calls. */
+static uintptr_t cros_oem_svc_smc_handler(uint32_t smc_fid, u_register_t x1,
+ u_register_t x2, u_register_t x3,
+ u_register_t x4, void *cookie,
+ void *handle, u_register_t flags)
+{
+ switch (smc_fid) {
+ case CROS_OEM_SMC_DRM_SET_TPM_AUTH_PUB_FUNC_ID:
+ return cros_write_data(&cros_oem_tpm_auth_pk, x1, x2, handle);
+ case CROS_OEM_SMC_DRM_SET_HARDWARE_UNIQUE_KEY_FUNC_ID:
+ return cros_write_data(&cros_oem_huk, x1, x2, handle);
+ case CROS_OEM_SMC_DRM_SET_ROOT_OF_TRUST_FUNC_ID:
+ return cros_write_data(&cros_oem_rot, x1, x2, handle);
+ default:
+ WARN("Unimplemented OEM Call: 0x%x\n", smc_fid);
+ SMC_RET1(handle, SMC_UNK);
+ }
+}
+
+/* Register OEM Service Calls as runtime service */
+DECLARE_RT_SVC(cros_oem_svc_smc_handler, OEN_OEM_START, OEN_OEM_END,
+ SMC_TYPE_FAST, NULL, cros_oem_svc_smc_handler);
diff --git a/services/spd/opteed/opteed.mk b/services/spd/opteed/opteed.mk
index f394744..289b3e7 100644
--- a/services/spd/opteed/opteed.mk
+++ b/services/spd/opteed/opteed.mk
@@ -33,3 +33,11 @@
$(eval $(call add_define,OPTEE_ALLOW_SMC_LOAD))
include lib/libfdt/libfdt.mk
endif
+
+CROS_WIDEVINE_SMC := 0
+ifeq ($(CROS_WIDEVINE_SMC),1)
+ifeq ($(OPTEE_ALLOW_SMC_LOAD),0)
+$(error When CROS_WIDEVINE_SMC=1, OPTEE_ALLOW_SMC_LOAD must also be 1)
+endif
+$(eval $(call add_define,CROS_WIDEVINE_SMC))
+endif
diff --git a/services/spd/opteed/opteed_main.c b/services/spd/opteed/opteed_main.c
index ab9896e..83b001a 100644
--- a/services/spd/opteed/opteed_main.c
+++ b/services/spd/opteed/opteed_main.c
@@ -33,6 +33,7 @@
#include <libfdt.h>
#endif /* OPTEE_ALLOW_SMC_LOAD */
#include <plat/common/platform.h>
+#include <services/oem/chromeos/widevine_smc_handlers.h>
#include <tools_share/uuid.h>
#include "opteed_private.h"
@@ -61,7 +62,7 @@
0xb1eafba3, 0x5d31, 0x4612, 0xb9, 0x06,
0xc4, 0xc7, 0xa4, 0xbe, 0x3c, 0xc0);
-#define OPTEED_FDT_SIZE 256
+#define OPTEED_FDT_SIZE 1024
static uint8_t fdt_buf[OPTEED_FDT_SIZE] __aligned(CACHE_WRITEBACK_GRANULE);
#else
@@ -299,6 +300,62 @@
}
#endif /* COREBOOT */
+#if CROS_WIDEVINE_SMC
+/*
+ * Adds a options/widevine node with the widevine table information to a device
+ * tree. Returns zero on success or if there is no widevine table information;
+ * failure code otherwise.
+ */
+static int add_options_widevine_node(void *fdt)
+{
+ int ret;
+
+ ret = fdt_begin_node(fdt, "options");
+ if (ret)
+ return ret;
+
+ ret = fdt_begin_node(fdt, "op-tee");
+ if (ret)
+ return ret;
+
+ ret = fdt_begin_node(fdt, "widevine");
+ if (ret)
+ return ret;
+
+ if (cros_oem_tpm_auth_pk.length) {
+ ret = fdt_property(fdt, "tcg,tpm-auth-public-key",
+ cros_oem_tpm_auth_pk.buffer,
+ cros_oem_tpm_auth_pk.length);
+ if (ret)
+ return ret;
+ }
+
+ if (cros_oem_huk.length) {
+ ret = fdt_property(fdt, "op-tee,hardware-unique-key",
+ cros_oem_huk.buffer, cros_oem_huk.length);
+ if (ret)
+ return ret;
+ }
+
+ if (cros_oem_rot.length) {
+ ret = fdt_property(fdt, "google,widevine-root-of-trust-ecc-p256",
+ cros_oem_rot.buffer, cros_oem_rot.length);
+ if (ret)
+ return ret;
+ }
+
+ ret = fdt_end_node(fdt);
+ if (ret)
+ return ret;
+
+ ret = fdt_end_node(fdt);
+ if (ret)
+ return ret;
+
+ return fdt_end_node(fdt);
+}
+#endif /* CROS_WIDEVINE_SMC */
+
/*
* Creates a device tree for passing into OP-TEE. Currently is populated with
* the coreboot table address.
@@ -326,6 +383,12 @@
return ret;
#endif /* COREBOOT */
+#if CROS_WIDEVINE_SMC
+ ret = add_options_widevine_node(fdt_buf);
+ if (ret)
+ return ret;
+#endif /* CROS_WIDEVINE_SMC */
+
ret = fdt_end_node(fdt_buf);
if (ret)
return ret;