From: khaalid <khaliidc...@gmail.com>
This command is intended to print or dump all UEFI runtime services.
The structure will look like efivar tool, since visually most people are
familiar with it. If the variable content is string then dump it as
string, otherwise for non string variables print them as raw hex; just
the way efivar command does.
Changes in v3:
- Command arguments, maybe this command is better if it doesn't have
any command argument, since we are printing only. Command options is
just unneccessary. And this is how many grub commands does, so it
should align.
- The size required for the buffer UTF-16, maybe the firmware already
did the formula so the bytes are as needed to store UTF-16. However
not sure so i implemented it. But if the firmware did already we
allocated large memory unneccesarily. We need to make sure.
- Other issues i fixed, as being suggested.
Signed-off-by: Khalid Ali <khaliidca...@gmail.com>
---
grub-core/Makefile.core.def | 4 +-
grub-core/commands/efi/lsefivar.c | 129 ++++++++++++++++++++++++++++++
2 files changed, 131 insertions(+), 2 deletions(-)
create mode 100644 grub-core/commands/efi/lsefivar.c
diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index ef3dc2dd0..8b9cf2a68 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -841,8 +841,8 @@ module = {
};
module = {
- name = efivar;
- efi = commands/efi/efivar.c;
+ name = lsefivar;
+ efi = commands/efi/lsefivar.c;
enable = efi;
};
diff --git a/grub-core/commands/efi/lsefivar.c
b/grub-core/commands/efi/lsefivar.c
new file mode 100644
index 000000000..013eca2f9
--- /dev/null
+++ b/grub-core/commands/efi/lsefivar.c
@@ -0,0 +1,129 @@
+/* efivar.c - dump runtime uefi variables. */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2025 Free Software Foundation, Inc.
+ *
+ * GRUB is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+
+#include <grub/dl.h>
+#include <grub/misc.h>
+#include <grub/charset.h>
+#include <grub/command.h>
+#include <grub/efi/efi.h>
+#include <grub/efi/api.h>
+#include <grub/lib/hexdump.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+
+static void
+dump_variable_data(const char *variable_name, grub_guid_t *variable_guid)
+{
+ grub_efi_status_t status;
+ grub_efi_uint32_t attributes;
+ grub_size_t data_size;
+ void *data;
+
+ status = grub_efi_get_variable_with_attributes(variable_name,
variable_guid,
+ &data_size, &data,
&attributes);
+ if (status != GRUB_EFI_SUCCESS)
+ {
+ grub_error(GRUB_ERR_IO, "failed to retrieve variable data 0x%"
PRIxGRUB_EFI_UINTN_T, status);
+ return;
+ }
+
+ grub_printf(_("Attributes:\n"));
+ if (attributes & GRUB_EFI_VARIABLE_NON_VOLATILE)
+ grub_printf(_("\tNon-Volatile\n"));
+ if (attributes & GRUB_EFI_VARIABLE_BOOTSERVICE_ACCESS)
+ grub_printf(_("\tBoot Service Access\n"));
+ if (attributes & GRUB_EFI_VARIABLE_RUNTIME_ACCESS)
+ grub_printf(_("\tRuntime Service Access\n"));
+
+ grub_printf(_("Value:\n"));
+ hexdump(0, data, data_size);
+ grub_free(data);
+}
+
+static grub_err_t
+dump_efi_variables(void)
+{
+ grub_efi_status_t status;
+ grub_efi_runtime_services_t *r;
+ grub_efi_uintn_t variable_name_size = 512;
+ grub_efi_char16_t *variable_name;
+ grub_uint8_t *variable_name_string = NULL;
+ grub_guid_t vendor_guid;
+
+ r = grub_efi_system_table->runtime_services;
+
+ variable_name = grub_calloc(variable_name_size,
sizeof(grub_efi_char16_t));
+ if (variable_name == NULL)
+ return grub_errno;
+ *variable_name = 0; /* Start with empty string */
+
+ while (1)
+ {
+ status = r->get_next_variable_name(&variable_name_size,
variable_name, &vendor_guid);
+ if (status == GRUB_EFI_NOT_FOUND)
+ break;
+ else if (status == GRUB_EFI_BUFFER_TOO_SMALL)
+ {
+ grub_dprintf("lsefivar", "buffer isn't enough,
enlarging up to %ld bytes\n",variable_name_size * sizeof(grub_efi_char16_t));
+ variable_name = grub_realloc(variable_name,
variable_name_size * sizeof(grub_efi_char16_t));
+ if (variable_name == NULL)
+ {
+ grub_free(variable_name);
+ return grub_errno;
+ }
+ }
+ variable_name_string = grub_calloc(variable_name_size,
GRUB_MAX_UTF8_PER_UTF16);
+ if (variable_name_string == NULL)
+ {
+ grub_free(variable_name);
+ return grub_errno;
+ }
+ *grub_utf16_to_utf8(variable_name_string, variable_name,
variable_name_size) = '\0';
+ grub_printf("%pG-%s\n",&vendor_guid, variable_name_string);
+ dump_variable_data((char*)variable_name_string, &vendor_guid);
+ }
+
+ grub_free(variable_name);
+ if (variable_name_string)
+ grub_free(variable_name_string);
+ return GRUB_ERR_NONE;
+}
+
+static grub_err_t
+grub_cmd_lsefivar (grub_command_t cmd __attribute__((unused)),
+ int argc __attribute__((unused)), char **argv
__attribute__((unused)))
+{
+ return dump_efi_variables();
+}
+
+static grub_command_t cmd;
+
+GRUB_MOD_INIT(lsefivar)
+{
+ cmd = grub_register_command("lsefivar", grub_cmd_lsefivar, NULL,
N_("Display UEFI variables."));
+}
+GRUB_MOD_FINI(lsefivar)
+{
+ grub_unregister_command(cmd);
+}
+
+
--
2.49.0
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