blob: 11066eb505dcfe7cd5d3dffdf6f37b069d3c957b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2020, Linaro Limited
*/
#define LOG_CATEGORY LOGC_EFI
#include <bootm.h>
#include <env.h>
#include <image.h>
#include <log.h>
#include <malloc.h>
#include <mapmem.h>
#include <dm.h>
#include <fs.h>
#include <efi_api.h>
#include <efi_load_initrd.h>
#include <efi_loader.h>
#include <efi_variable.h>
#include <linux/libfdt.h>
#include <linux/list.h>
#if defined(CONFIG_CMD_EFIDEBUG) || defined(CONFIG_EFI_LOAD_FILE2_INITRD)
/* GUID used by Linux to identify the LoadFile2 protocol with the initrd */
const efi_guid_t efi_lf2_initrd_guid = EFI_INITRD_MEDIA_GUID;
#endif
/**
* efi_create_current_boot_var() - Return Boot#### name were #### is replaced by
* the value of BootCurrent
*
* @var_name: variable name
* @var_name_size: size of var_name
*
* Return: Status code
*/
static efi_status_t efi_create_current_boot_var(u16 var_name[],
size_t var_name_size)
{
efi_uintn_t boot_current_size;
efi_status_t ret;
u16 boot_current;
u16 *pos;
boot_current_size = sizeof(boot_current);
ret = efi_get_variable_int(u"BootCurrent",
&efi_global_variable_guid, NULL,
&boot_current_size, &boot_current, NULL);
if (ret != EFI_SUCCESS)
goto out;
pos = efi_create_indexed_name(var_name, var_name_size, "Boot",
boot_current);
if (!pos) {
ret = EFI_OUT_OF_RESOURCES;
goto out;
}
out:
return ret;
}
/**
* efi_get_dp_from_boot() - Retrieve and return a device path from an EFI
* Boot### variable.
* A boot option may contain an array of device paths.
* We use a VenMedia() with a specific GUID to identify
* the usage of the array members. This function is
* used to extract a specific device path
*
* @guid: vendor GUID of the VenMedia() device path node identifying the
* device path
*
* Return: device path or NULL. Caller must free the returned value
*/
struct efi_device_path *efi_get_dp_from_boot(const efi_guid_t guid)
{
struct efi_load_option lo;
void *var_value;
efi_uintn_t size;
efi_status_t ret;
u16 var_name[16];
ret = efi_create_current_boot_var(var_name, sizeof(var_name));
if (ret != EFI_SUCCESS)
return NULL;
var_value = efi_get_var(var_name, &efi_global_variable_guid, &size);
if (!var_value)
return NULL;
ret = efi_deserialize_load_option(&lo, var_value, &size);
if (ret != EFI_SUCCESS)
goto err;
return efi_dp_from_lo(&lo, &guid);
err:
free(var_value);
return NULL;
}
const struct guid_to_hash_map {
efi_guid_t guid;
const char algo[32];
u32 bits;
} guid_to_hash[] = {
{
EFI_CERT_X509_SHA256_GUID,
"sha256",
SHA256_SUM_LEN * 8,
},
{
EFI_CERT_SHA256_GUID,
"sha256",
SHA256_SUM_LEN * 8,
},
{
EFI_CERT_X509_SHA384_GUID,
"sha384",
SHA384_SUM_LEN * 8,
},
{
EFI_CERT_X509_SHA512_GUID,
"sha512",
SHA512_SUM_LEN * 8,
},
};
#define MAX_GUID_TO_HASH_COUNT ARRAY_SIZE(guid_to_hash)
/** guid_to_sha_str - return the sha string e.g "sha256" for a given guid
* used on EFI security databases
*
* @guid: guid to check
*
* Return: len or 0 if no match is found
*/
const char *guid_to_sha_str(const efi_guid_t *guid)
{
size_t i;
for (i = 0; i < MAX_GUID_TO_HASH_COUNT; i++) {
if (!guidcmp(guid, &guid_to_hash[i].guid))
return guid_to_hash[i].algo;
}
return NULL;
}
/** algo_to_len - return the sha size in bytes for a given string
*
* @algo: string indicating hashing algorithm to check
*
* Return: length of hash in bytes or 0 if no match is found
*/
int algo_to_len(const char *algo)
{
size_t i;
for (i = 0; i < MAX_GUID_TO_HASH_COUNT; i++) {
if (!strcmp(algo, guid_to_hash[i].algo))
return guid_to_hash[i].bits / 8;
}
return 0;
}
/** efi_link_dev - link the efi_handle_t and udevice
*
* @handle: efi handle to associate with udevice
* @dev: udevice to associate with efi handle
*
* Return: 0 on success, negative on failure
*/
int efi_link_dev(efi_handle_t handle, struct udevice *dev)
{
handle->dev = dev;
return dev_tag_set_ptr(dev, DM_TAG_EFI, handle);
}
/**
* efi_unlink_dev() - unlink udevice and handle
*
* @handle: EFI handle to unlink
*
* Return: 0 on success, negative on failure
*/
int efi_unlink_dev(efi_handle_t handle)
{
int ret;
ret = dev_tag_del(handle->dev, DM_TAG_EFI);
if (ret)
return ret;
handle->dev = NULL;
return 0;
}
static int u16_tohex(u16 c)
{
if (c >= '0' && c <= '9')
return c - '0';
if (c >= 'A' && c <= 'F')
return c - 'A' + 10;
/* not hexadecimal */
return -1;
}
bool efi_varname_is_load_option(u16 *var_name16, int *index)
{
int id, i, digit;
if (memcmp(var_name16, u"Boot", 8))
return false;
for (id = 0, i = 0; i < 4; i++) {
digit = u16_tohex(var_name16[4 + i]);
if (digit < 0)
break;
id = (id << 4) + digit;
}
if (i == 4 && !var_name16[8]) {
if (index)
*index = id;
return true;
}
return false;
}
/**
* efi_next_variable_name() - get next variable name
*
* This function is a wrapper of efi_get_next_variable_name_int().
* If efi_get_next_variable_name_int() returns EFI_BUFFER_TOO_SMALL,
* @size and @buf are updated by new buffer size and realloced buffer.
*
* @size: pointer to the buffer size
* @buf: pointer to the buffer
* @guid: pointer to the guid
* Return: status code
*/
efi_status_t efi_next_variable_name(efi_uintn_t *size, u16 **buf, efi_guid_t *guid)
{
u16 *p;
efi_status_t ret;
efi_uintn_t buf_size = *size;
ret = efi_get_next_variable_name_int(&buf_size, *buf, guid);
if (ret == EFI_NOT_FOUND)
return ret;
if (ret == EFI_BUFFER_TOO_SMALL) {
p = realloc(*buf, buf_size);
if (!p)
return EFI_OUT_OF_RESOURCES;
*buf = p;
*size = buf_size;
ret = efi_get_next_variable_name_int(&buf_size, *buf, guid);
}
return ret;
}
/**
* efi_search_bootorder() - search the boot option index in BootOrder
*
* @bootorder: pointer to the BootOrder variable
* @num: number of BootOrder entry
* @target: target boot option index to search
* @index: pointer to store the index of BootOrder variable
* Return: true if exists, false otherwise
*/
bool efi_search_bootorder(u16 *bootorder, efi_uintn_t num, u32 target, u32 *index)
{
u32 i;
for (i = 0; i < num; i++) {
if (target == bootorder[i]) {
if (index)
*index = i;
return true;
}
}
return false;
}
/**
* efi_env_set_load_options() - set load options from environment variable
*
* @handle: the image handle
* @env_var: name of the environment variable
* @load_options: pointer to load options (output)
* Return: status code
*/
efi_status_t efi_env_set_load_options(efi_handle_t handle,
const char *env_var,
u16 **load_options)
{
const char *env = env_get(env_var);
size_t size;
u16 *pos;
efi_status_t ret;
*load_options = NULL;
if (!env)
return EFI_SUCCESS;
size = sizeof(u16) * (utf8_utf16_strlen(env) + 1);
pos = calloc(size, 1);
if (!pos)
return EFI_OUT_OF_RESOURCES;
*load_options = pos;
utf8_utf16_strcpy(&pos, env);
ret = efi_set_load_options(handle, size, *load_options);
if (ret != EFI_SUCCESS) {
free(*load_options);
*load_options = NULL;
}
return ret;
}
/**
* copy_fdt() - Copy the device tree to a new location available to EFI
*
* The FDT is copied to a suitable location within the EFI memory map.
* Additional 12 KiB are added to the space in case the device tree needs to be
* expanded later with fdt_open_into().
*
* @fdtp: On entry a pointer to the flattened device tree.
* On exit a pointer to the copy of the flattened device tree.
* FDT start
* Return: status code
*/
static efi_status_t copy_fdt(void **fdtp)
{
unsigned long fdt_ram_start = -1L, fdt_pages;
efi_status_t ret = 0;
void *fdt, *new_fdt;
u64 new_fdt_addr;
uint fdt_size;
int i;
for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
u64 ram_start = gd->bd->bi_dram[i].start;
u64 ram_size = gd->bd->bi_dram[i].size;
if (!ram_size)
continue;
if (ram_start < fdt_ram_start)
fdt_ram_start = ram_start;
}
/*
* Give us at least 12 KiB of breathing room in case the device tree
* needs to be expanded later.
*/
fdt = *fdtp;
fdt_pages = efi_size_in_pages(fdt_totalsize(fdt) + 0x3000);
fdt_size = fdt_pages << EFI_PAGE_SHIFT;
ret = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES,
EFI_ACPI_RECLAIM_MEMORY, fdt_pages,
&new_fdt_addr);
if (ret != EFI_SUCCESS) {
log_err("ERROR: Failed to reserve space for FDT\n");
goto done;
}
new_fdt = (void *)(uintptr_t)new_fdt_addr;
memcpy(new_fdt, fdt, fdt_totalsize(fdt));
fdt_set_totalsize(new_fdt, fdt_size);
*fdtp = (void *)(uintptr_t)new_fdt_addr;
done:
return ret;
}
/**
* get_config_table() - get configuration table
*
* @guid: GUID of the configuration table
* Return: pointer to configuration table or NULL
*/
static void *get_config_table(const efi_guid_t *guid)
{
size_t i;
for (i = 0; i < systab.nr_tables; i++) {
if (!guidcmp(guid, &systab.tables[i].guid))
return systab.tables[i].table;
}
return NULL;
}
/**
* efi_install_fdt() - install device tree
*
* If fdt is not EFI_FDT_USE_INTERNAL, the device tree located at that memory
* address will be installed as configuration table, otherwise the device
* tree located at the address indicated by environment variable fdt_addr or as
* fallback fdtcontroladdr will be used.
*
* On architectures using ACPI tables device trees shall not be installed as
* configuration table.
*
* @fdt: address of device tree or EFI_FDT_USE_INTERNAL to use
* the hardware device tree as indicated by environment variable
* fdt_addr or as fallback the internal device tree as indicated by
* the environment variable fdtcontroladdr
* Return: status code
*/
efi_status_t efi_install_fdt(void *fdt)
{
struct bootm_headers img = { 0 };
efi_status_t ret;
/*
* The EBBR spec requires that we have either an FDT or an ACPI table
* but not both.
*/
if (CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE) && fdt)
log_warning("WARNING: Can't have ACPI table and device tree - ignoring DT.\n");
if (fdt == EFI_FDT_USE_INTERNAL) {
const char *fdt_opt;
uintptr_t fdt_addr;
/* Look for device tree that is already installed */
if (get_config_table(&efi_guid_fdt))
return EFI_SUCCESS;
/* Check if there is a hardware device tree */
fdt_opt = env_get("fdt_addr");
/* Use our own device tree as fallback */
if (!fdt_opt) {
fdt_opt = env_get("fdtcontroladdr");
if (!fdt_opt) {
log_err("ERROR: need device tree\n");
return EFI_NOT_FOUND;
}
}
fdt_addr = hextoul(fdt_opt, NULL);
if (!fdt_addr) {
log_err("ERROR: invalid $fdt_addr or $fdtcontroladdr\n");
return EFI_LOAD_ERROR;
}
fdt = map_sysmem(fdt_addr, 0);
}
/* Install device tree */
if (fdt_check_header(fdt)) {
log_err("ERROR: invalid device tree\n");
return EFI_LOAD_ERROR;
}
/* Create memory reservations as indicated by the device tree */
efi_carve_out_dt_rsv(fdt);
if (CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE))
return EFI_SUCCESS;
/* Prepare device tree for payload */
ret = copy_fdt(&fdt);
if (ret) {
log_err("ERROR: out of memory\n");
return EFI_OUT_OF_RESOURCES;
}
if (image_setup_libfdt(&img, fdt, NULL)) {
log_err("ERROR: failed to process device tree\n");
return EFI_LOAD_ERROR;
}
efi_try_purge_kaslr_seed(fdt);
if (CONFIG_IS_ENABLED(EFI_TCG2_PROTOCOL_MEASURE_DTB)) {
ret = efi_tcg2_measure_dtb(fdt);
if (ret == EFI_SECURITY_VIOLATION) {
log_err("ERROR: failed to measure DTB\n");
return ret;
}
}
/* Install device tree as UEFI table */
ret = efi_install_configuration_table(&efi_guid_fdt, fdt);
if (ret != EFI_SUCCESS) {
log_err("ERROR: failed to install device tree\n");
return ret;
}
return EFI_SUCCESS;
}
/**
* do_bootefi_exec() - execute EFI binary
*
* The image indicated by @handle is started. When it returns the allocated
* memory for the @load_options is freed.
*
* @handle: handle of loaded image
* @load_options: load options
* Return: status code
*
* Load the EFI binary into a newly assigned memory unwinding the relocation
* information, install the loaded image protocol, and call the binary.
*/
efi_status_t do_bootefi_exec(efi_handle_t handle, void *load_options)
{
efi_status_t ret;
efi_uintn_t exit_data_size = 0;
u16 *exit_data = NULL;
struct efi_event *evt;
/* On ARM switch from EL3 or secure mode to EL2 or non-secure mode */
switch_to_non_secure_mode();
/*
* The UEFI standard requires that the watchdog timer is set to five
* minutes when invoking an EFI boot option.
*
* Unified Extensible Firmware Interface (UEFI), version 2.7 Errata A
* 7.5. Miscellaneous Boot Services - EFI_BOOT_SERVICES.SetWatchdogTimer
*/
ret = efi_set_watchdog(300);
if (ret != EFI_SUCCESS) {
log_err("ERROR: Failed to set watchdog timer\n");
goto out;
}
/* Call our payload! */
ret = EFI_CALL(efi_start_image(handle, &exit_data_size, &exit_data));
if (ret != EFI_SUCCESS) {
log_err("## Application failed, r = %lu\n",
ret & ~EFI_ERROR_MASK);
if (exit_data) {
log_err("## %ls\n", exit_data);
efi_free_pool(exit_data);
}
}
efi_restore_gd();
out:
free(load_options);
if (IS_ENABLED(CONFIG_EFI_LOAD_FILE2_INITRD)) {
if (efi_initrd_deregister() != EFI_SUCCESS)
log_err("Failed to remove loadfile2 for initrd\n");
}
/* Notify EFI_EVENT_GROUP_RETURN_TO_EFIBOOTMGR event group. */
list_for_each_entry(evt, &efi_events, link) {
if (evt->group &&
!guidcmp(evt->group,
&efi_guid_event_group_return_to_efibootmgr)) {
efi_signal_event(evt);
EFI_CALL(systab.boottime->close_event(evt));
break;
}
}
/* Control is returned to U-Boot, disable EFI watchdog */
efi_set_watchdog(0);
return ret;
}