Mirrors/u-boot
2
0
Fork 0
mirror of https://github.com/AsahiLinux/u-boot synced 2024-11-24 21:54:01 +00:00
Code Issues Projects Releases Packages Wiki Activity

efi_loader: Implement EFI variable handling via OP-TEE

Browse source 
In OP-TEE we can run EDK2's StandAloneMM on a secure partition.
StandAloneMM is responsible for the UEFI variable support. In
combination with OP-TEE and it's U-Boot supplicant, variables are
authenticated/validated in secure world and stored on an RPMB partition.

So let's add a new config option in U-Boot implementing the necessary
calls to OP-TEE for the variable management.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Pipat Methavanitpong <pipat1010@gmail.com>
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This commit is contained in:
Ilias Apalodimas 2020-05-17 22:25:44 +03:00 committed by Heinrich Schuchardt
parent 23a397d2e2
commit f042e47e8f
3 changed files with 675 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
lib/efi_loader/Kconfig
View file

@ -164,4 +164,13 @@ config EFI_SECURE_BOOT
it is signed with a trusted key. To do that, you need to install,
at least, PK, KEK and db.
config EFI_MM_COMM_TEE
bool "UEFI variables storage service via OP-TEE"
depends on OPTEE
default n
help
If OP-TEE is present and running StandAloneMM, dispatch all UEFI variable
related operations to that. The application will verify, authenticate and
store the variables on an RPMB.
endif

4
lib/efi_loader/Makefile
View file

@ -35,7 +35,11 @@ obj-y += efi_root_node.o
obj-y += efi_runtime.o
obj-y += efi_setup.o
obj-$(CONFIG_EFI_UNICODE_COLLATION_PROTOCOL2) += efi_unicode_collation.o
ifeq ($(CONFIG_EFI_MM_COMM_TEE),y)
obj-y += efi_variable_tee.o
else
obj-y += efi_variable.o
endif
obj-y += efi_watchdog.o
obj-$(CONFIG_LCD) += efi_gop.o
obj-$(CONFIG_DM_VIDEO) += efi_gop.o

662
lib/efi_loader/efi_variable_tee.c Normal file
View file

@ -0,0 +1,662 @@
// SPDX-License-Identifier: GPL-2.0+
/*
* EFI variable service via OP-TEE
*
* Copyright (C) 2019 Linaro Ltd. <sughosh.ganu@linaro.org>
* Copyright (C) 2019 Linaro Ltd. <ilias.apalodimas@linaro.org>
*/
#include <common.h>
#include <efi.h>
#include <efi_api.h>
#include <efi_loader.h>
#include <tee.h>
#include <malloc.h>
#include <mm_communication.h>
static efi_uintn_t max_buffer_size; /* comm + var + func + data */
static efi_uintn_t max_payload_size; /* func + data */
struct mm_connection {
struct udevice *tee;
u32 session;
};
/**
* get_connection() - Retrieve OP-TEE session for a specific UUID.
*
* @conn: session buffer to fill
* Return: status code
*/
static int get_connection(struct mm_connection *conn)
{
static const struct tee_optee_ta_uuid uuid = PTA_STMM_UUID;
struct udevice *tee = NULL;
struct tee_open_session_arg arg;
int rc;
tee = tee_find_device(tee, NULL, NULL, NULL);
if (!tee)
return -ENODEV;
memset(&arg, 0, sizeof(arg));
tee_optee_ta_uuid_to_octets(arg.uuid, &uuid);
rc = tee_open_session(tee, &arg, 0, NULL);
if (!rc) {
conn->tee = tee;
conn->session = arg.session;
}
return rc;
}
/**
* optee_mm_communicate() - Pass a buffer to StandaloneMM running in OP-TEE
*
* @comm_buf: locally allocted communcation buffer
* @dsize: buffer size
* Return: status code
*/
static efi_status_t optee_mm_communicate(void *comm_buf, ulong dsize)
{
ulong buf_size;
efi_status_t ret;
struct efi_mm_communicate_header *mm_hdr;
struct mm_connection conn = { NULL, 0 };
struct tee_invoke_arg arg;
struct tee_param param[2];
struct tee_shm *shm = NULL;
int rc;
if (!comm_buf)
return EFI_INVALID_PARAMETER;
mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
buf_size = mm_hdr->message_len + sizeof(efi_guid_t) + sizeof(size_t);
if (dsize != buf_size)
return EFI_INVALID_PARAMETER;
rc = get_connection(&conn);
if (rc) {
log_err("Unable to open OP-TEE session (err=%d)\n", rc);
return EFI_UNSUPPORTED;
}
if (tee_shm_register(conn.tee, comm_buf, buf_size, 0, &shm)) {
log_err("Unable to register shared memory\n");
return EFI_UNSUPPORTED;
}
memset(&arg, 0, sizeof(arg));
arg.func = PTA_STMM_CMDID_COMMUNICATE;
arg.session = conn.session;
memset(param, 0, sizeof(param));
param[0].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INOUT;
param[0].u.memref.size = buf_size;
param[0].u.memref.shm = shm;
param[1].attr = TEE_PARAM_ATTR_TYPE_VALUE_OUTPUT;
rc = tee_invoke_func(conn.tee, &arg, 2, param);
if (rc)
return EFI_INVALID_PARAMETER;
tee_shm_free(shm);
tee_close_session(conn.tee, conn.session);
switch (param[1].u.value.a) {
case ARM_SMC_MM_RET_SUCCESS:
ret = EFI_SUCCESS;
break;
case ARM_SMC_MM_RET_INVALID_PARAMS:
ret = EFI_INVALID_PARAMETER;
break;
case ARM_SMC_MM_RET_DENIED:
ret = EFI_ACCESS_DENIED;
break;
case ARM_SMC_MM_RET_NO_MEMORY:
ret = EFI_OUT_OF_RESOURCES;
break;
default:
ret = EFI_ACCESS_DENIED;
}
return ret;
}
/**
* mm_communicate() - Adjust the cmonnucation buffer to StandAlonneMM and send
* it to OP-TEE
*
* @comm_buf: locally allocted communcation buffer
* @dsize: buffer size
* Return: status code
*/
static efi_status_t mm_communicate(u8 *comm_buf, efi_uintn_t dsize)
{
efi_status_t ret;
struct efi_mm_communicate_header *mm_hdr;
struct smm_variable_communicate_header *var_hdr;
dsize += MM_COMMUNICATE_HEADER_SIZE + MM_VARIABLE_COMMUNICATE_SIZE;
mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data;
ret = optee_mm_communicate(comm_buf, dsize);
if (ret != EFI_SUCCESS) {
log_err("%s failed!\n", __func__);
return ret;
}
return var_hdr->ret_status;
}
/**
* setup_mm_hdr() - Allocate a buffer for StandAloneMM and initialize the
* header data.
*
* @dptr: pointer address of the corresponding StandAloneMM
* function
* @payload_size: buffer size
* @func: standAloneMM function number
* @ret: EFI return code
* Return: buffer or NULL
*/
static u8 *setup_mm_hdr(void **dptr, efi_uintn_t payload_size,
efi_uintn_t func, efi_status_t *ret)
{
const efi_guid_t mm_var_guid = EFI_MM_VARIABLE_GUID;
struct efi_mm_communicate_header *mm_hdr;
struct smm_variable_communicate_header *var_hdr;
u8 *comm_buf;
/* In the init function we initialize max_buffer_size with
* get_max_payload(). So skip the test if max_buffer_size is initialized
* StandAloneMM will perform similar checks and drop the buffer if it's
* too long
*/
if (max_buffer_size && max_buffer_size <
(MM_COMMUNICATE_HEADER_SIZE +
MM_VARIABLE_COMMUNICATE_SIZE +
payload_size)) {
*ret = EFI_INVALID_PARAMETER;
return NULL;
}
comm_buf = calloc(1, MM_COMMUNICATE_HEADER_SIZE +
MM_VARIABLE_COMMUNICATE_SIZE +
payload_size);
if (!comm_buf) {
*ret = EFI_OUT_OF_RESOURCES;
return NULL;
}
mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
guidcpy(&mm_hdr->header_guid, &mm_var_guid);
mm_hdr->message_len = MM_VARIABLE_COMMUNICATE_SIZE + payload_size;
var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data;
var_hdr->function = func;
if (dptr)
*dptr = var_hdr->data;
*ret = EFI_SUCCESS;
return comm_buf;
}
/**
* get_max_payload() - Get variable payload size from StandAloneMM.
*
* @size: size of the variable in storage
* Return: status code
*/
efi_status_t EFIAPI get_max_payload(efi_uintn_t *size)
{
struct smm_variable_payload_size *var_payload = NULL;
efi_uintn_t payload_size;
u8 *comm_buf = NULL;
efi_status_t ret;
if (!size) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
payload_size = sizeof(*var_payload);
comm_buf = setup_mm_hdr((void **)&var_payload, payload_size,
SMM_VARIABLE_FUNCTION_GET_PAYLOAD_SIZE, &ret);
if (!comm_buf)
goto out;
ret = mm_communicate(comm_buf, payload_size);
if (ret != EFI_SUCCESS)
goto out;
*size = var_payload->size;
out:
free(comm_buf);
return ret;
}
/**
* efi_get_variable() - retrieve value of a UEFI variable
*
* This function implements the GetVariable runtime service.
*
* See the Unified Extensible Firmware Interface (UEFI) specification for
* details.
*
* @name: name of the variable
* @guid: vendor GUID
* @attr: attributes of the variable
* @data_size: size of the buffer to which the variable value is copied
* @data: buffer to which the variable value is copied
* Return: status code
*/
efi_status_t EFIAPI efi_get_variable(u16 *name, const efi_guid_t *guid,
u32 *attr, efi_uintn_t *data_size,
void *data)
{
struct smm_variable_access *var_acc;
efi_uintn_t payload_size;
efi_uintn_t name_size;
efi_uintn_t tmp_dsize;
u8 *comm_buf = NULL;
efi_status_t ret;
EFI_ENTRY("\"%ls\" %pUl %p %p %p", name, guid, attr, data_size, data);
if (!name || !guid || !data_size) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
/* Check payload size */
name_size = u16_strsize(name);
if (name_size > max_payload_size - MM_VARIABLE_ACCESS_HEADER_SIZE) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
/* Trim output buffer size */
tmp_dsize = *data_size;
if (name_size + tmp_dsize >
max_payload_size - MM_VARIABLE_ACCESS_HEADER_SIZE) {
tmp_dsize = max_payload_size -
MM_VARIABLE_ACCESS_HEADER_SIZE -
name_size;
}
/* Get communication buffer and initialize header */
payload_size = MM_VARIABLE_ACCESS_HEADER_SIZE + name_size + tmp_dsize;
comm_buf = setup_mm_hdr((void **)&var_acc, payload_size,
SMM_VARIABLE_FUNCTION_GET_VARIABLE, &ret);
if (!comm_buf)
goto out;
/* Fill in contents */
guidcpy(&var_acc->guid, guid);
var_acc->data_size = tmp_dsize;
var_acc->name_size = name_size;
var_acc->attr = attr ? *attr : 0;
memcpy(var_acc->name, name, name_size);
/* Communicate */
ret = mm_communicate(comm_buf, payload_size);
if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) {
/* Update with reported data size for trimmed case */
*data_size = var_acc->data_size;
}
if (ret != EFI_SUCCESS)
goto out;
if (attr)
*attr = var_acc->attr;
if (data)
memcpy(data, (u8 *)var_acc->name + var_acc->name_size,
var_acc->data_size);
else
ret = EFI_INVALID_PARAMETER;
out:
free(comm_buf);
return EFI_EXIT(ret);
}
/**
* efi_get_next_variable_name() - enumerate the current variable names
*
* @variable_name_size: size of variable_name buffer in bytes
* @variable_name: name of uefi variable's name in u16
* @guid: vendor's guid
*
* This function implements the GetNextVariableName service.
*
* See the Unified Extensible Firmware Interface (UEFI) specification for
* details.
*
* Return: status code
*/
efi_status_t EFIAPI efi_get_next_variable_name(efi_uintn_t *variable_name_size,
u16 *variable_name,
efi_guid_t *guid)
{
struct smm_variable_getnext *var_getnext;
efi_uintn_t payload_size;
efi_uintn_t out_name_size;
efi_uintn_t in_name_size;
efi_uintn_t tmp_dsize;
efi_uintn_t name_size;
u8 *comm_buf = NULL;
efi_status_t ret;
EFI_ENTRY("%p \"%ls\" %pUl", variable_name_size, variable_name, guid);
if (!variable_name_size || !variable_name || !guid) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
out_name_size = *variable_name_size;
in_name_size = u16_strsize(variable_name);
if (out_name_size < in_name_size) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
name_size = u16_strsize(variable_name);
if (name_size > max_payload_size - MM_VARIABLE_GET_NEXT_HEADER_SIZE) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
/* Trim output buffer size */
tmp_dsize = *variable_name_size;
if (name_size + tmp_dsize >
max_payload_size - MM_VARIABLE_GET_NEXT_HEADER_SIZE) {
tmp_dsize = max_payload_size -
MM_VARIABLE_GET_NEXT_HEADER_SIZE -
name_size;
}
payload_size = MM_VARIABLE_GET_NEXT_HEADER_SIZE + out_name_size;
comm_buf = setup_mm_hdr((void **)&var_getnext, payload_size,
SMM_VARIABLE_FUNCTION_GET_NEXT_VARIABLE_NAME,
&ret);
if (!comm_buf)
goto out;
/* Fill in contents */
guidcpy(&var_getnext->guid, guid);
var_getnext->name_size = out_name_size;
memcpy(var_getnext->name, variable_name, in_name_size);
memset((u8 *)var_getnext->name + in_name_size, 0x0,
out_name_size - in_name_size);
/* Communicate */
ret = mm_communicate(comm_buf, payload_size);
if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) {
/* Update with reported data size for trimmed case */
*variable_name_size = var_getnext->name_size;
}
if (ret != EFI_SUCCESS)
goto out;
guidcpy(guid, &var_getnext->guid);
memcpy(variable_name, (u8 *)var_getnext->name,
var_getnext->name_size);
out:
free(comm_buf);
return EFI_EXIT(ret);
}
/**
* efi_set_variable() - set value of a UEFI variable
*
* This function implements the SetVariable runtime service.
*
* See the Unified Extensible Firmware Interface (UEFI) specification for
* details.
*
* @name: name of the variable
* @guid: vendor GUID
* @attr: attributes of the variable
* @data_size: size of the buffer with the variable value
* @data: buffer with the variable value
* Return: status code
*/
efi_status_t EFIAPI efi_set_variable(u16 *name, const efi_guid_t *guid,
u32 attr, efi_uintn_t data_size,
const void *data)
{
struct smm_variable_access *var_acc;
efi_uintn_t payload_size;
efi_uintn_t name_size;
u8 *comm_buf = NULL;
efi_status_t ret;
EFI_ENTRY("\"%ls\" %pUl %x %zu %p", name, guid, attr, data_size, data);
if (!name || name[0] == 0 || !guid) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
if (data_size > 0 && !data) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
/* Check payload size */
name_size = u16_strsize(name);
payload_size = MM_VARIABLE_ACCESS_HEADER_SIZE + name_size + data_size;
if (payload_size > max_payload_size) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
/* Get communication buffer and initialize header */
comm_buf = setup_mm_hdr((void **)&var_acc, payload_size,
SMM_VARIABLE_FUNCTION_SET_VARIABLE, &ret);
if (!comm_buf)
goto out;
/* Fill in contents */
guidcpy(&var_acc->guid, guid);
var_acc->data_size = data_size;
var_acc->name_size = name_size;
var_acc->attr = attr;
memcpy(var_acc->name, name, name_size);
memcpy((u8 *)var_acc->name + name_size, data, data_size);
/* Communicate */
ret = mm_communicate(comm_buf, payload_size);
out:
free(comm_buf);
return EFI_EXIT(ret);
}
/**
* efi_query_variable_info() - get information about EFI variables
*
* This function implements the QueryVariableInfo() runtime service.
*
* See the Unified Extensible Firmware Interface (UEFI) specification for
* details.
*
* @attributes: bitmask to select variables to be
* queried
* @maximum_variable_storage_size: maximum size of storage area for the
* selected variable types
* @remaining_variable_storage_size: remaining size of storage are for the
* selected variable types
* @maximum_variable_size: maximum size of a variable of the
* selected type
* Returns: status code
*/
efi_status_t EFIAPI __efi_runtime
efi_query_variable_info(u32 attributes, u64 *max_variable_storage_size,
u64 *remain_variable_storage_size,
u64 *max_variable_size)
{
struct smm_variable_query_info *mm_query_info;
efi_uintn_t payload_size;
efi_status_t ret;
u8 *comm_buf;
EFI_ENTRY("%x %p %p %p", attributes, max_variable_storage_size,
remain_variable_storage_size, max_variable_size);
payload_size = sizeof(*mm_query_info);
comm_buf = setup_mm_hdr((void **)&mm_query_info, payload_size,
SMM_VARIABLE_FUNCTION_QUERY_VARIABLE_INFO,
&ret);
if (!comm_buf)
goto out;
mm_query_info->attr = attributes;
ret = mm_communicate(comm_buf, payload_size);
if (ret != EFI_SUCCESS)
goto out;
*max_variable_storage_size = mm_query_info->max_variable_storage;
*remain_variable_storage_size =
mm_query_info->remaining_variable_storage;
*max_variable_size = mm_query_info->max_variable_size;
out:
free(comm_buf);
return EFI_EXIT(ret);
}
/**
* efi_get_variable_runtime() - runtime implementation of GetVariable()
*
* @variable_name: name of the variable
* @guid: vendor GUID
* @attributes: attributes of the variable
* @data_size: size of the buffer to which the variable value is copied
* @data: buffer to which the variable value is copied
* Return: status code
*/
static efi_status_t __efi_runtime EFIAPI
efi_get_variable_runtime(u16 *variable_name, const efi_guid_t *guid,
u32 *attributes, efi_uintn_t *data_size, void *data)
{
return EFI_UNSUPPORTED;
}
/**
* efi_get_next_variable_name_runtime() - runtime implementation of
* GetNextVariable()
*
* @variable_name_size: size of variable_name buffer in byte
* @variable_name: name of uefi variable's name in u16
* @guid: vendor's guid
* Return: status code
*/
static efi_status_t __efi_runtime EFIAPI
efi_get_next_variable_name_runtime(efi_uintn_t *variable_name_size,
u16 *variable_name, efi_guid_t *guid)
{
return EFI_UNSUPPORTED;
}
/**
* efi_query_variable_info() - get information about EFI variables
*
* This function implements the QueryVariableInfo() runtime service.
*
* See the Unified Extensible Firmware Interface (UEFI) specification for
* details.
*
* @attributes: bitmask to select variables to be
* queried
* @maximum_variable_storage_size: maximum size of storage area for the
* selected variable types
* @remaining_variable_storage_size: remaining size of storage are for the
* selected variable types
* @maximum_variable_size: maximum size of a variable of the
* selected type
* Return: status code
*/
efi_status_t EFIAPI __efi_runtime
efi_query_variable_info_runtime(u32 attributes, u64 *max_variable_storage_size,
u64 *remain_variable_storage_size,
u64 *max_variable_size)
{
return EFI_UNSUPPORTED;
}
/**
* efi_set_variable_runtime() - runtime implementation of SetVariable()
*
* @variable_name: name of the variable
* @guid: vendor GUID
* @attributes: attributes of the variable
* @data_size: size of the buffer with the variable value
* @data: buffer with the variable value
* Return: status code
*/
static efi_status_t __efi_runtime EFIAPI
efi_set_variable_runtime(u16 *variable_name, const efi_guid_t *guid,
u32 attributes, efi_uintn_t data_size,
const void *data)
{
return EFI_UNSUPPORTED;
}
/**
* efi_variables_boot_exit_notify() - notify ExitBootServices() is called
*/
void efi_variables_boot_exit_notify(void)
{
u8 *comm_buf;
efi_status_t ret;
comm_buf = setup_mm_hdr(NULL, 0,
SMM_VARIABLE_FUNCTION_EXIT_BOOT_SERVICE, &ret);
if (comm_buf)
ret = mm_communicate(comm_buf, 0);
else
ret = EFI_NOT_FOUND;
if (ret != EFI_SUCCESS)
log_err("Unable to notify StMM for ExitBootServices\n");
free(comm_buf);
/* Update runtime service table */
efi_runtime_services.query_variable_info =
efi_query_variable_info_runtime;
efi_runtime_services.get_variable = efi_get_variable_runtime;
efi_runtime_services.get_next_variable_name =
efi_get_next_variable_name_runtime;
efi_runtime_services.set_variable = efi_set_variable_runtime;
efi_update_table_header_crc32(&efi_runtime_services.hdr);
}
/**
* efi_init_variables() - initialize variable services
*
* Return: status code
*/
efi_status_t efi_init_variables(void)
{
efi_status_t ret;
ret = get_max_payload(&max_payload_size);
if (ret != EFI_SUCCESS)
return ret;
max_buffer_size = MM_COMMUNICATE_HEADER_SIZE +
MM_VARIABLE_COMMUNICATE_SIZE +
max_payload_size;
return EFI_SUCCESS;
}