smallsolar/u-boot
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Add command to set an environment variable to an EFI variable

Browse Source 
We may want to make things conditional on EFI variable state

Signed-off-by: Matthew Garrett <mgarrett@aurora.tech>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Matthew Garrett
2024-11-23 11:55:09 -08:00
committed by Simon Glass
parent de05434022
commit 652a64a686
3 changed files with 138 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
cmd/Kconfig
View File

@@ -761,6 +761,10 @@ config CMD_NVEDIT_SELECT
help
Select the compiled-in persistent storage of environment variables.
config CMD_EFI_GET_ENV
bool "efi get env"
help
Set an environment variable to the contents of an EFI variable
endmenu
menu "Memory commands"

1
cmd/Makefile
View File

@@ -70,6 +70,7 @@ obj-$(CONFIG_CMD_EEPROM) += eeprom.o
obj-$(CONFIG_EFI) += efi.o efi_common.o
obj-$(CONFIG_CMD_EFIDEBUG) += efidebug.o efi_common.o
obj-$(CONFIG_CMD_EFICONFIG) += eficonfig.o
obj-$(CONFIG_CMD_EFI_GET_ENV) += efigetenv.o
ifdef CONFIG_CMD_EFICONFIG
ifdef CONFIG_EFI_MM_COMM_TEE
obj-$(CONFIG_EFI_SECURE_BOOT) += eficonfig_sbkey.o

133
cmd/efigetenv.c Normal file
View File

@@ -0,0 +1,133 @@
// SPDX-License-Identifier: GPL-2.0+
#include <charset.h>
#include <command.h>
#include <efi_loader.h>
#include <efi_variable.h>
#include <env.h>
#include <hexdump.h>
#include <malloc.h>
#include <uuid.h>
/* Set a U-Boot environment variable to the contents of a UEFI variable */
int do_efi_get_env(struct cmd_tbl *cmdtb, int flat, int argc, char *const argv[])
{
u16 *var_name = NULL;
char *strdata = NULL;
efi_uintn_t size = 0;
bool var_content_is_utf16_string = false;
efi_status_t ret;
efi_guid_t guid;
u8 *data = NULL;
u32 attributes;
size_t len;
u64 time;
u16 *p;
ret = efi_init_obj_list();
if (ret != EFI_SUCCESS) {
printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
ret & ~EFI_ERROR_MASK);
return CMD_RET_FAILURE;
}
argv++;
argc--;
if (argc != 3 && argc != 4)
return CMD_RET_USAGE;
if (argc == 4) {
if (strcmp(argv[0], "-s"))
return CMD_RET_USAGE;
var_content_is_utf16_string = true;
argv++;
argc--;
}
len = utf8_utf16_strnlen(argv[0], strlen(argv[0]));
var_name = malloc((len + 1) * 2);
if (!var_name) {
printf("## Out of memory\n");
return CMD_RET_FAILURE;
}
p = var_name;
utf8_utf16_strncpy(&p, argv[0], len + 1);
if (uuid_str_to_bin(argv[1], guid.b, UUID_STR_FORMAT_GUID)) {
ret = CMD_RET_USAGE;
goto out;
}
ret = efi_get_variable_int(var_name, &guid, &attributes, &size, data,
&time);
if (ret == EFI_BUFFER_TOO_SMALL) {
data = malloc(size);
if (!data) {
printf("## Out of memory\n");
ret = CMD_RET_FAILURE;
goto out;
}
ret = efi_get_variable_int(var_name, &guid, &attributes,
&size, data, &time);
}
if (ret == EFI_NOT_FOUND) {
printf("Error: \"%ls\" not defined\n", var_name);
ret = CMD_RET_FAILURE;
goto out;
}
if (ret != EFI_SUCCESS) {
printf("Error: Cannot read variable, r = %lu\n",
ret & ~EFI_ERROR_MASK);
ret = CMD_RET_FAILURE;
goto out;
}
if (var_content_is_utf16_string) {
char *p;
len = utf16_utf8_strnlen((u16 *)data, size / 2);
strdata = malloc(len + 1);
if (!strdata) {
printf("## Out of memory\n");
ret = CMD_RET_FAILURE;
goto out;
}
p = strdata;
utf16_utf8_strncpy(&p, (u16 *)data, size / 2);
} else {
len = size * 2;
strdata = malloc(len + 1);
if (!strdata) {
printf("## Out of memory\n");
ret = CMD_RET_FAILURE;
goto out;
}
bin2hex(strdata, data, size);
}
strdata[len] = '\0';
ret = env_set(argv[2], strdata);
if (ret) {
ret = CMD_RET_FAILURE;
goto out;
}
ret = CMD_RET_SUCCESS;
out:
free(strdata);
free(data);
free(var_name);
return ret;
}
U_BOOT_CMD(
efigetenv, 5, 4, do_efi_get_env,
"set environment variable to content of EFI variable",
"[-s] name guid envvar\n"
" - set environment variable 'envvar' to the EFI variable 'name'-'guid'\n"
" \"-s\": Interpret the EFI variable value as a UTF-16 string\n"
);