@@ -17651,6 +17651,12 @@ L: linux-arm-msm@vger.kernel.org
S: Maintained
F: drivers/firmware/qcom_qseecom.c
+QUALCOMM QSEECOM UEFISECAPP DRIVER
+M: Maximilian Luz <luzmaximilian@gmail.com>
+L: linux-arm-msm@vger.kernel.org
+S: Maintained
+F: drivers/firmware/qcom_qseecom_uefisecapp.c
+
QUALCOMM RMNET DRIVER
M: Subash Abhinov Kasiviswanathan <quic_subashab@quicinc.com>
M: Sean Tranchetti <quic_stranche@quicinc.com>
@@ -242,6 +242,22 @@ config QCOM_QSEECOM
Select Y here to enable the QSEECOM interface driver.
+config QCOM_QSEECOM_UEFISECAPP
+ bool "Qualcomm SEE UEFI Secure App client driver"
+ depends on QCOM_QSEECOM
+ depends on EFI
+ help
+ Various Qualcomm SoCs do not allow direct access to EFI variables.
+ Instead, these need to be accessed via the UEFI Secure Application
+ (uefisecapp), residing in the Secure Execution Environment (SEE).
+
+ This module provides a client driver for uefisecapp, installing efivar
+ operations to allow the kernel accessing EFI variables, and via that also
+ provide user-space with access to EFI variables via efivarfs.
+
+ Select Y here to provide access to EFI variables on the aforementioned
+ platforms.
+
config SYSFB
bool
select BOOT_VESA_SUPPORT
@@ -21,6 +21,7 @@ obj-$(CONFIG_FW_CFG_SYSFS) += qemu_fw_cfg.o
obj-$(CONFIG_QCOM_SCM) += qcom-scm.o
qcom-scm-objs += qcom_scm.o qcom_scm-smc.o qcom_scm-legacy.o
obj-$(CONFIG_QCOM_QSEECOM) += qcom_qseecom.o
+obj-$(CONFIG_QCOM_QSEECOM_UEFISECAPP) += qcom_qseecom_uefisecapp.o
obj-$(CONFIG_SYSFB) += sysfb.o
obj-$(CONFIG_SYSFB_SIMPLEFB) += sysfb_simplefb.o
obj-$(CONFIG_TI_SCI_PROTOCOL) += ti_sci.o
@@ -83,7 +83,9 @@ static int qseecom_client_register(struct platform_device *qseecom_dev,
* assuming the app has already been loaded (usually by firmware bootloaders)
* and its ID can be queried successfully.
*/
-static const struct qseecom_app_desc qcom_qseecom_apps[] = {};
+static const struct qseecom_app_desc qcom_qseecom_apps[] = {
+ { "qcom.tz.uefisecapp", "uefisecapp" },
+};
static int qcom_qseecom_probe(struct platform_device *qseecom_dev)
{
new file mode 100644
@@ -0,0 +1,871 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Client driver for Qualcomm UEFI Secure Application (qcom.tz.uefisecapp).
+ * Provides access to UEFI variables on platforms where they are secured by the
+ * aforementioned Secure Execution Environment (SEE) application.
+ *
+ * Copyright (C) 2023 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <linux/efi.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/ucs2_string.h>
+
+#include <linux/firmware/qcom/qcom_qseecom.h>
+
+/* -- Qualcomm "uefisecapp" interface definitions. -------------------------- */
+
+/* Maximum length of name string with null-terminator */
+#define QSEE_MAX_NAME_LEN 1024
+
+#define QSEE_CMD_UEFI(x) (0x8000 | (x))
+#define QSEE_CMD_UEFI_GET_VARIABLE QSEE_CMD_UEFI(0)
+#define QSEE_CMD_UEFI_SET_VARIABLE QSEE_CMD_UEFI(1)
+#define QSEE_CMD_UEFI_GET_NEXT_VARIABLE QSEE_CMD_UEFI(2)
+#define QSEE_CMD_UEFI_QUERY_VARIABLE_INFO QSEE_CMD_UEFI(3)
+
+/**
+ * struct qsee_req_uefi_get_variable - Request for GetVariable command.
+ * @command_id: The ID of the command. Must be %QSEE_CMD_UEFI_GET_VARIABLE.
+ * @length: Length of the request in bytes, including this struct and any
+ * parameters (name, GUID) stored after it as well as any padding
+ * thereof for alignment.
+ * @name_offset: Offset from the start of this struct to where the variable
+ * name is stored (as utf-16 string), in bytes.
+ * @name_size: Size of the name parameter in bytes, including null-terminator.
+ * @guid_offset: Offset from the start of this struct to where the GUID
+ * parameter is stored, in bytes.
+ * @guid_size: Size of the GUID parameter in bytes, i.e. sizeof(efi_guid_t).
+ * @data_size: Size of the output buffer, in bytes.
+ */
+struct qsee_req_uefi_get_variable {
+ u32 command_id;
+ u32 length;
+ u32 name_offset;
+ u32 name_size;
+ u32 guid_offset;
+ u32 guid_size;
+ u32 data_size;
+} __packed;
+
+/**
+ * struct qsee_rsp_uefi_get_variable - Response for GetVariable command.
+ * @command_id: The ID of the command. Should be %QSEE_CMD_UEFI_GET_VARIABLE.
+ * @length: Length of the response in bytes, including this struct and the
+ * returned data.
+ * @status: Status of this command.
+ * @attributes: EFI variable attributes.
+ * @data_offset: Offset from the start of this struct to where the data is
+ * stored, in bytes.
+ * @data_size: Size of the returned data, in bytes. In case status indicates
+ * that the buffer is too small, this will be the size required
+ * to store the EFI variable data.
+ */
+struct qsee_rsp_uefi_get_variable {
+ u32 command_id;
+ u32 length;
+ u32 status;
+ u32 attributes;
+ u32 data_offset;
+ u32 data_size;
+} __packed;
+
+/**
+ * struct qsee_req_uefi_set_variable - Request for the SetVariable command.
+ * @command_id: The ID of the command. Must be %QSEE_CMD_UEFI_SET_VARIABLE.
+ * @length: Length of the request in bytes, including this struct and any
+ * parameters (name, GUID, data) stored after it as well as any
+ * padding thereof required for alignment.
+ * @name_offset: Offset from the start of this struct to where the variable
+ * name is stored (as utf-16 string), in bytes.
+ * @name_size: Size of the name parameter in bytes, including null-terminator.
+ * @guid_offset: Offset from the start of this struct to where the GUID
+ * parameter is stored, in bytes.
+ * @guid_size: Size of the GUID parameter in bytes, i.e. sizeof(efi_guid_t).
+ * @attributes: The EFI variable attributes to set for this variable.
+ * @data_offset: Offset from the start of this struct to where the EFI variable
+ * data is stored, in bytes.
+ * @data_size: Size of EFI variable data, in bytes.
+ *
+ */
+struct qsee_req_uefi_set_variable {
+ u32 command_id;
+ u32 length;
+ u32 name_offset;
+ u32 name_size;
+ u32 guid_offset;
+ u32 guid_size;
+ u32 attributes;
+ u32 data_offset;
+ u32 data_size;
+} __packed;
+
+/**
+ * struct qsee_rsp_uefi_set_variable - Response for the SetVariable command.
+ * @command_id: The ID of the command. Should be %QSEE_CMD_UEFI_SET_VARIABLE.
+ * @length: The length of this response, i.e. the size of this struct in
+ * bytes.
+ * @status: Status of this command.
+ * @_unknown1: Unknown response field.
+ * @_unknown2: Unknown response field.
+ */
+struct qsee_rsp_uefi_set_variable {
+ u32 command_id;
+ u32 length;
+ u32 status;
+ u32 _unknown1;
+ u32 _unknown2;
+} __packed;
+
+/**
+ * struct qsee_req_uefi_get_next_variable - Request for the
+ * GetNextVariableName command.
+ * @command_id: The ID of the command. Must be
+ * %QSEE_CMD_UEFI_GET_NEXT_VARIABLE.
+ * @length: Length of the request in bytes, including this struct and any
+ * parameters (name, GUID) stored after it as well as any padding
+ * thereof for alignment.
+ * @guid_offset: Offset from the start of this struct to where the GUID
+ * parameter is stored, in bytes.
+ * @guid_size: Size of the GUID parameter in bytes, i.e. sizeof(efi_guid_t).
+ * @name_offset: Offset from the start of this struct to where the variable
+ * name is stored (as utf-16 string), in bytes.
+ * @name_size: Size of the name parameter in bytes, including null-terminator.
+ */
+struct qsee_req_uefi_get_next_variable {
+ u32 command_id;
+ u32 length;
+ u32 guid_offset;
+ u32 guid_size;
+ u32 name_offset;
+ u32 name_size;
+} __packed;
+
+/**
+ * struct qsee_rsp_uefi_get_next_variable - Response for the
+ * GetNextVariableName command.
+ * @command_id: The ID of the command. Should be
+ * %QSEE_CMD_UEFI_GET_NEXT_VARIABLE.
+ * @length: Length of the response in bytes, including this struct and any
+ * parameters (name, GUID) stored after it as well as any padding
+ * thereof for alignment.
+ * @status: Status of this command.
+ * @guid_offset: Offset from the start of this struct to where the GUID
+ * parameter is stored, in bytes.
+ * @guid_size: Size of the GUID parameter in bytes, i.e. sizeof(efi_guid_t).
+ * @name_offset: Offset from the start of this struct to where the variable
+ * name is stored (as utf-16 string), in bytes.
+ * @name_size: Size of the name parameter in bytes, including null-terminator.
+ */
+struct qsee_rsp_uefi_get_next_variable {
+ u32 command_id;
+ u32 length;
+ u32 status;
+ u32 guid_offset;
+ u32 guid_size;
+ u32 name_offset;
+ u32 name_size;
+} __packed;
+
+/**
+ * struct qsee_req_uefi_query_variable_info - Response for the
+ * GetNextVariableName command.
+ * @command_id: The ID of the command. Must be
+ * %QSEE_CMD_UEFI_QUERY_VARIABLE_INFO.
+ * @length: The length of this request, i.e. the size of this struct in
+ * bytes.
+ * @attributes: The storage attributes to query the info for.
+ */
+struct qsee_req_uefi_query_variable_info {
+ u32 command_id;
+ u32 length;
+ u32 attributes;
+} __packed;
+
+/**
+ * struct qsee_rsp_uefi_query_variable_info - Response for the
+ * GetNextVariableName command.
+ * @command_id: The ID of the command. Must be
+ * %QSEE_CMD_UEFI_QUERY_VARIABLE_INFO.
+ * @length: The length of this response, i.e. the size of this
+ * struct in bytes.
+ * @status: Status of this command.
+ * @_pad: Padding.
+ * @storage_space: Full storage space size, in bytes.
+ * @remaining_space: Free storage space available, in bytes.
+ * @max_variable_size: Maximum variable data size, in bytes.
+ */
+struct qsee_rsp_uefi_query_variable_info {
+ u32 command_id;
+ u32 length;
+ u32 status;
+ u32 _pad;
+ u64 storage_space;
+ u64 remaining_space;
+ u64 max_variable_size;
+} __packed;
+
+/* -- Alignment helpers ----------------------------------------------------- */
+
+/*
+ * Helper macro to ensure proper alignment of types (fields and arrays) when
+ * stored in some (contiguous) buffer.
+ *
+ * Note: The driver from which this one has been reverse-engineered expects an
+ * alignment of 8 bytes (64 bits) for GUIDs. Our definition of efi_guid_t,
+ * however, has an alignment of 4 byte (32 bits). So far, this seems to work
+ * fine here. See also the comment on the typedef of efi_guid_t.
+ */
+#define qcuefi_buf_align_fields(fields...) \
+ ({ \
+ size_t __len = 0; \
+ fields \
+ __len; \
+ })
+
+#define __field_impl(size, align, offset) \
+ ({ \
+ size_t *__offset = (offset); \
+ size_t __aligned; \
+ \
+ __aligned = ALIGN(__len, align); \
+ __len = __aligned + (size); \
+ \
+ if (__offset) \
+ *__offset = __aligned; \
+ });
+
+#define __array_offs(type, count, offset) \
+ __field_impl(sizeof(type) * (count), __alignof__(type), offset)
+
+#define __array(type, count) __array_offs(type, count, NULL)
+#define __field_offs(type, offset) __array_offs(type, 1, offset)
+#define __field(type) __array_offs(type, 1, NULL)
+
+/* -- UEFI app interface. --------------------------------------------------- */
+
+struct qcuefi_client {
+ struct qseecom_client *client;
+ struct efivars efivars;
+};
+
+static struct device *qcuefi_dev(struct qcuefi_client *qcuefi)
+{
+ return &qcuefi->client->aux_dev.dev;
+}
+
+static efi_status_t qsee_uefi_status_to_efi(u32 status)
+{
+ u64 category = status & 0xf0000000;
+ u64 code = status & 0x0fffffff;
+
+ return category << (BITS_PER_LONG - 32) | code;
+}
+
+static efi_status_t qsee_uefi_get_variable(struct qcuefi_client *qcuefi, const efi_char16_t *name,
+ const efi_guid_t *guid, u32 *attributes,
+ unsigned long *data_size, void *data)
+{
+ struct qsee_req_uefi_get_variable *req_data;
+ struct qsee_rsp_uefi_get_variable *rsp_data;
+ unsigned long buffer_size = *data_size;
+ efi_status_t efi_status = EFI_SUCCESS;
+ unsigned long name_length;
+ size_t guid_offs;
+ size_t name_offs;
+ size_t req_size;
+ size_t rsp_size;
+ ssize_t status;
+
+ if (!name || !guid)
+ return EFI_INVALID_PARAMETER;
+
+ name_length = ucs2_strnlen(name, QSEE_MAX_NAME_LEN) + 1;
+ if (name_length > QSEE_MAX_NAME_LEN)
+ return EFI_INVALID_PARAMETER;
+
+ if (buffer_size && !data)
+ return EFI_INVALID_PARAMETER;
+
+ req_size = qcuefi_buf_align_fields(
+ __field(*req_data)
+ __array_offs(*name, name_length, &name_offs)
+ __field_offs(*guid, &guid_offs)
+ );
+
+ rsp_size = qcuefi_buf_align_fields(
+ __field(*rsp_data)
+ __array(u8, buffer_size)
+ );
+
+ req_data = kzalloc(req_size, GFP_KERNEL);
+ if (!req_data) {
+ efi_status = EFI_OUT_OF_RESOURCES;
+ goto out;
+ }
+
+ rsp_data = kzalloc(rsp_size, GFP_KERNEL);
+ if (!rsp_data) {
+ efi_status = EFI_OUT_OF_RESOURCES;
+ goto out_free_req;
+ }
+
+ req_data->command_id = QSEE_CMD_UEFI_GET_VARIABLE;
+ req_data->data_size = buffer_size;
+ req_data->name_offset = name_offs;
+ req_data->name_size = name_length * sizeof(*name);
+ req_data->guid_offset = guid_offs;
+ req_data->guid_size = sizeof(*guid);
+ req_data->length = req_size;
+
+ status = ucs2_strscpy(((void *)req_data) + req_data->name_offset, name, name_length);
+ if (status < 0)
+ return EFI_INVALID_PARAMETER;
+
+ memcpy(((void *)req_data) + req_data->guid_offset, guid, req_data->guid_size);
+
+ status = qcom_qseecom_app_send(qcuefi->client, req_data, req_size, rsp_data, rsp_size);
+ if (status) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->command_id != QSEE_CMD_UEFI_GET_VARIABLE) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->length < sizeof(*rsp_data)) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->status) {
+ dev_dbg(qcuefi_dev(qcuefi), "%s: uefisecapp error: 0x%x\n",
+ __func__, rsp_data->status);
+ efi_status = qsee_uefi_status_to_efi(rsp_data->status);
+
+ /* Update size and attributes in case buffer is too small. */
+ if (efi_status == EFI_BUFFER_TOO_SMALL) {
+ *data_size = rsp_data->data_size;
+ if (attributes)
+ *attributes = rsp_data->attributes;
+ }
+
+ goto out_free;
+ }
+
+ if (rsp_data->length > rsp_size) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->data_offset + rsp_data->data_size > rsp_data->length) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ /*
+ * Note: We need to set attributes and data size even if the buffer is
+ * too small and we won't copy any data. This is described in spec, so
+ * that callers can either allocate a buffer properly (with two calls
+ * to this function) or just read back attributes withouth having to
+ * deal with that.
+ *
+ * Specifically:
+ * - If we have a buffer size of zero and no buffer, just return the
+ * attributes, required size, and indicate success.
+ * - If the buffer size is nonzero but too small, indicate that as an
+ * error.
+ * - Otherwise, we are good to copy the data.
+ *
+ * Note that we have already ensured above that the buffer pointer is
+ * non-NULL if its size is nonzero.
+ */
+ *data_size = rsp_data->data_size;
+ if (attributes)
+ *attributes = rsp_data->attributes;
+
+ if (buffer_size == 0 && !data) {
+ efi_status = EFI_SUCCESS;
+ goto out_free;
+ }
+
+ if (buffer_size < rsp_data->data_size) {
+ efi_status = EFI_BUFFER_TOO_SMALL;
+ goto out_free;
+ }
+
+ memcpy(data, ((void *)rsp_data) + rsp_data->data_offset, rsp_data->data_size);
+
+out_free:
+ kfree(rsp_data);
+out_free_req:
+ kfree(req_data);
+out:
+ return efi_status;
+}
+
+static efi_status_t qsee_uefi_set_variable(struct qcuefi_client *qcuefi, const efi_char16_t *name,
+ const efi_guid_t *guid, u32 attributes,
+ unsigned long data_size, const void *data)
+{
+ struct qsee_req_uefi_set_variable *req_data;
+ struct qsee_rsp_uefi_set_variable *rsp_data;
+ efi_status_t efi_status = EFI_SUCCESS;
+ unsigned long name_length;
+ size_t name_offs;
+ size_t guid_offs;
+ size_t data_offs;
+ size_t req_size;
+ ssize_t status;
+
+ if (!name || !guid)
+ return EFI_INVALID_PARAMETER;
+
+ name_length = ucs2_strnlen(name, QSEE_MAX_NAME_LEN) + 1;
+ if (name_length > QSEE_MAX_NAME_LEN)
+ return EFI_INVALID_PARAMETER;
+
+ /*
+ * Make sure we have some data if data_size is nonzero. Note that using
+ * a size of zero is a valid use-case described in spec and deletes the
+ * variable.
+ */
+ if (data_size && !data)
+ return EFI_INVALID_PARAMETER;
+
+ req_size = qcuefi_buf_align_fields(
+ __field(*req_data)
+ __array_offs(*name, name_length, &name_offs)
+ __field_offs(*guid, &guid_offs)
+ __array_offs(u8, data_size, &data_offs)
+ );
+
+ req_data = kzalloc(req_size, GFP_KERNEL);
+ if (!req_data) {
+ efi_status = EFI_OUT_OF_RESOURCES;
+ goto out;
+ }
+
+ rsp_data = kzalloc(sizeof(*rsp_data), GFP_KERNEL);
+ if (!rsp_data) {
+ efi_status = EFI_OUT_OF_RESOURCES;
+ goto out_free_req;
+ }
+
+ req_data->command_id = QSEE_CMD_UEFI_SET_VARIABLE;
+ req_data->attributes = attributes;
+ req_data->name_offset = name_offs;
+ req_data->name_size = name_length * sizeof(*name);
+ req_data->guid_offset = guid_offs;
+ req_data->guid_size = sizeof(*guid);
+ req_data->data_offset = data_offs;
+ req_data->data_size = data_size;
+ req_data->length = req_size;
+
+ status = ucs2_strscpy(((void *)req_data) + req_data->name_offset, name, name_length);
+ if (status < 0)
+ return EFI_INVALID_PARAMETER;
+
+ memcpy(((void *)req_data) + req_data->guid_offset, guid, req_data->guid_size);
+
+ if (data_size)
+ memcpy(((void *)req_data) + req_data->data_offset, data, req_data->data_size);
+
+ status = qcom_qseecom_app_send(qcuefi->client, req_data, req_size, rsp_data,
+ sizeof(*rsp_data));
+ if (status) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->command_id != QSEE_CMD_UEFI_SET_VARIABLE) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->length != sizeof(*rsp_data)) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->status) {
+ dev_dbg(qcuefi_dev(qcuefi), "%s: uefisecapp error: 0x%x\n",
+ __func__, rsp_data->status);
+ efi_status = qsee_uefi_status_to_efi(rsp_data->status);
+ }
+
+out_free:
+ kfree(rsp_data);
+out_free_req:
+ kfree(req_data);
+out:
+ return efi_status;
+}
+
+static efi_status_t qsee_uefi_get_next_variable(struct qcuefi_client *qcuefi,
+ unsigned long *name_size, efi_char16_t *name,
+ efi_guid_t *guid)
+{
+ struct qsee_req_uefi_get_next_variable *req_data;
+ struct qsee_rsp_uefi_get_next_variable *rsp_data;
+ efi_status_t efi_status = EFI_SUCCESS;
+ size_t guid_offs;
+ size_t name_offs;
+ size_t req_size;
+ size_t rsp_size;
+ ssize_t status;
+
+ if (!name_size || !name || !guid)
+ return EFI_INVALID_PARAMETER;
+
+ if (*name_size == 0)
+ return EFI_INVALID_PARAMETER;
+
+ req_size = qcuefi_buf_align_fields(
+ __field(*req_data)
+ __field_offs(*guid, &guid_offs)
+ __array_offs(*name, *name_size / sizeof(*name), &name_offs)
+ );
+
+ rsp_size = qcuefi_buf_align_fields(
+ __field(*rsp_data)
+ __field(*guid)
+ __array(*name, *name_size / sizeof(*name))
+ );
+
+ req_data = kzalloc(req_size, GFP_KERNEL);
+ if (!req_data) {
+ efi_status = EFI_OUT_OF_RESOURCES;
+ goto out;
+ }
+
+ rsp_data = kzalloc(rsp_size, GFP_KERNEL);
+ if (!rsp_data) {
+ efi_status = EFI_OUT_OF_RESOURCES;
+ goto out_free_req;
+ }
+
+ req_data->command_id = QSEE_CMD_UEFI_GET_NEXT_VARIABLE;
+ req_data->guid_offset = guid_offs;
+ req_data->guid_size = sizeof(*guid);
+ req_data->name_offset = name_offs;
+ req_data->name_size = *name_size;
+ req_data->length = req_size;
+
+ memcpy(((void *)req_data) + req_data->guid_offset, guid, req_data->guid_size);
+ status = ucs2_strscpy(((void *)req_data) + req_data->name_offset, name,
+ *name_size / sizeof(*name));
+ if (status < 0)
+ return EFI_INVALID_PARAMETER;
+
+ status = qcom_qseecom_app_send(qcuefi->client, req_data, req_size, rsp_data, rsp_size);
+ if (status) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->command_id != QSEE_CMD_UEFI_GET_NEXT_VARIABLE) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->length < sizeof(*rsp_data)) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->status) {
+ dev_dbg(qcuefi_dev(qcuefi), "%s: uefisecapp error: 0x%x\n",
+ __func__, rsp_data->status);
+ efi_status = qsee_uefi_status_to_efi(rsp_data->status);
+
+ /*
+ * If the buffer to hold the name is too small, update the
+ * name_size with the required size, so that callers can
+ * reallocate it accordingly.
+ */
+ if (efi_status == EFI_BUFFER_TOO_SMALL)
+ *name_size = rsp_data->name_size;
+
+ goto out_free;
+ }
+
+ if (rsp_data->length > rsp_size) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->name_offset + rsp_data->name_size > rsp_data->length) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->guid_offset + rsp_data->guid_size > rsp_data->length) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->name_size > *name_size) {
+ *name_size = rsp_data->name_size;
+ efi_status = EFI_BUFFER_TOO_SMALL;
+ goto out_free;
+ }
+
+ if (rsp_data->guid_size != sizeof(*guid)) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ memcpy(guid, ((void *)rsp_data) + rsp_data->guid_offset, rsp_data->guid_size);
+ status = ucs2_strscpy(name, ((void *)rsp_data) + rsp_data->name_offset,
+ rsp_data->name_size / sizeof(*name));
+ *name_size = rsp_data->name_size;
+
+ if (status < 0) {
+ /*
+ * Return EFI_DEVICE_ERROR here because the buffer size should
+ * have already been validated above, causing this function to
+ * bail with EFI_BUFFER_TOO_SMALL.
+ */
+ return EFI_DEVICE_ERROR;
+ }
+
+out_free:
+ kfree(rsp_data);
+out_free_req:
+ kfree(req_data);
+out:
+ return efi_status;
+}
+
+static efi_status_t qsee_uefi_query_variable_info(struct qcuefi_client *qcuefi, u32 attr,
+ u64 *storage_space, u64 *remaining_space,
+ u64 *max_variable_size)
+{
+ struct qsee_req_uefi_query_variable_info *req_data;
+ struct qsee_rsp_uefi_query_variable_info *rsp_data;
+ efi_status_t efi_status = EFI_SUCCESS;
+ int status;
+
+ req_data = kzalloc(sizeof(*req_data), GFP_KERNEL);
+ if (!req_data) {
+ efi_status = EFI_OUT_OF_RESOURCES;
+ goto out;
+ }
+
+ rsp_data = kzalloc(sizeof(*rsp_data), GFP_KERNEL);
+ if (!rsp_data) {
+ efi_status = EFI_OUT_OF_RESOURCES;
+ goto out_free_req;
+ }
+
+ req_data->command_id = QSEE_CMD_UEFI_QUERY_VARIABLE_INFO;
+ req_data->attributes = attr;
+ req_data->length = sizeof(*req_data);
+
+ status = qcom_qseecom_app_send(qcuefi->client, req_data, sizeof(*req_data), rsp_data,
+ sizeof(*rsp_data));
+ if (status) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->command_id != QSEE_CMD_UEFI_QUERY_VARIABLE_INFO) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->length != sizeof(*rsp_data)) {
+ efi_status = EFI_DEVICE_ERROR;
+ goto out_free;
+ }
+
+ if (rsp_data->status) {
+ dev_dbg(qcuefi_dev(qcuefi), "%s: uefisecapp error: 0x%x\n",
+ __func__, rsp_data->status);
+ efi_status = qsee_uefi_status_to_efi(rsp_data->status);
+ goto out_free;
+ }
+
+ if (storage_space)
+ *storage_space = rsp_data->storage_space;
+
+ if (remaining_space)
+ *remaining_space = rsp_data->remaining_space;
+
+ if (max_variable_size)
+ *max_variable_size = rsp_data->max_variable_size;
+
+out_free:
+ kfree(rsp_data);
+out_free_req:
+ kfree(req_data);
+out:
+ return efi_status;
+}
+
+/* -- Global efivar interface. ---------------------------------------------- */
+
+static struct qcuefi_client *__qcuefi;
+static DEFINE_MUTEX(__qcuefi_lock);
+
+static int qcuefi_set_reference(struct qcuefi_client *qcuefi)
+{
+ mutex_lock(&__qcuefi_lock);
+
+ if (qcuefi && __qcuefi) {
+ mutex_unlock(&__qcuefi_lock);
+ return -EEXIST;
+ }
+
+ __qcuefi = qcuefi;
+
+ mutex_unlock(&__qcuefi_lock);
+ return 0;
+}
+
+static struct qcuefi_client *qcuefi_acquire(void)
+{
+ mutex_lock(&__qcuefi_lock);
+ return __qcuefi;
+}
+
+static void qcuefi_release(void)
+{
+ mutex_unlock(&__qcuefi_lock);
+}
+
+static efi_status_t qcuefi_get_variable(efi_char16_t *name, efi_guid_t *vendor, u32 *attr,
+ unsigned long *data_size, void *data)
+{
+ struct qcuefi_client *qcuefi;
+ efi_status_t status;
+
+ qcuefi = qcuefi_acquire();
+ if (!qcuefi)
+ return EFI_NOT_READY;
+
+ status = qsee_uefi_get_variable(qcuefi, name, vendor, attr, data_size, data);
+
+ qcuefi_release();
+ return status;
+}
+
+static efi_status_t qcuefi_set_variable(efi_char16_t *name, efi_guid_t *vendor,
+ u32 attr, unsigned long data_size, void *data)
+{
+ struct qcuefi_client *qcuefi;
+ efi_status_t status;
+
+ qcuefi = qcuefi_acquire();
+ if (!qcuefi)
+ return EFI_NOT_READY;
+
+ status = qsee_uefi_set_variable(qcuefi, name, vendor, attr, data_size, data);
+
+ qcuefi_release();
+ return status;
+}
+
+static efi_status_t qcuefi_get_next_variable(unsigned long *name_size, efi_char16_t *name,
+ efi_guid_t *vendor)
+{
+ struct qcuefi_client *qcuefi;
+ efi_status_t status;
+
+ qcuefi = qcuefi_acquire();
+ if (!qcuefi)
+ return EFI_NOT_READY;
+
+ status = qsee_uefi_get_next_variable(qcuefi, name_size, name, vendor);
+
+ qcuefi_release();
+ return status;
+}
+
+static efi_status_t qcuefi_query_variable_info(u32 attr, u64 *storage_space, u64 *remaining_space,
+ u64 *max_variable_size)
+{
+ struct qcuefi_client *qcuefi;
+ efi_status_t status;
+
+ qcuefi = qcuefi_acquire();
+ if (!qcuefi)
+ return EFI_NOT_READY;
+
+ status = qsee_uefi_query_variable_info(qcuefi, attr, storage_space, remaining_space,
+ max_variable_size);
+
+ qcuefi_release();
+ return status;
+}
+
+static const struct efivar_operations qcom_efivar_ops = {
+ .get_variable = qcuefi_get_variable,
+ .set_variable = qcuefi_set_variable,
+ .get_next_variable = qcuefi_get_next_variable,
+ .query_variable_info = qcuefi_query_variable_info,
+};
+
+/* -- Driver setup. --------------------------------------------------------- */
+
+static int qcom_uefisecapp_probe(struct auxiliary_device *aux_dev,
+ const struct auxiliary_device_id *aux_dev_id)
+{
+ struct qcuefi_client *qcuefi;
+ int status;
+
+ qcuefi = devm_kzalloc(&aux_dev->dev, sizeof(*qcuefi), GFP_KERNEL);
+ if (!qcuefi)
+ return -ENOMEM;
+
+ qcuefi->client = container_of(aux_dev, struct qseecom_client, aux_dev);
+
+ auxiliary_set_drvdata(aux_dev, qcuefi);
+ status = qcuefi_set_reference(qcuefi);
+ if (status)
+ return status;
+
+ status = efivars_register(&qcuefi->efivars, &qcom_efivar_ops);
+ if (status)
+ qcuefi_set_reference(NULL);
+
+ return status;
+}
+
+static void qcom_uefisecapp_remove(struct auxiliary_device *aux_dev)
+{
+ struct qcuefi_client *qcuefi = auxiliary_get_drvdata(aux_dev);
+
+ efivars_unregister(&qcuefi->efivars);
+ qcuefi_set_reference(NULL);
+}
+
+static const struct auxiliary_device_id qcom_uefisecapp_id_table[] = {
+ { .name = "qcom_qseecom.uefisecapp" },
+ {}
+};
+MODULE_DEVICE_TABLE(auxiliary, qcom_uefisecapp_id_table);
+
+static struct auxiliary_driver qcom_uefisecapp_driver = {
+ .probe = qcom_uefisecapp_probe,
+ .remove = qcom_uefisecapp_remove,
+ .id_table = qcom_uefisecapp_id_table,
+ .driver = {
+ .name = "qcom_qseecom_uefisecapp",
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+module_auxiliary_driver(qcom_uefisecapp_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Client driver for Qualcomm SEE UEFI Secure App");
+MODULE_LICENSE("GPL");