blob: 2f0b91a353d1ab41480cc537b4e277eccac78328 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2023, Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
*
* smbiosdump.efi saves the SMBIOS table as file.
*
* Specifying 'nocolor' as load option data suppresses colored output and
* clearing of the screen.
*/
#include <efi_api.h>
#include <part.h>
#include <smbios.h>
#include <string.h>
#define BUFFER_SIZE 64
static struct efi_simple_text_output_protocol *cerr;
static struct efi_simple_text_output_protocol *cout;
static struct efi_simple_text_input_protocol *cin;
static struct efi_boot_services *bs;
static efi_handle_t handle;
static struct efi_system_table *systable;
static const efi_guid_t smbios_guid = SMBIOS_TABLE_GUID;
static const efi_guid_t smbios3_guid = SMBIOS3_TABLE_GUID;
static const efi_guid_t loaded_image_guid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
static const efi_guid_t guid_simple_file_system_protocol =
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
static const efi_guid_t efi_system_partition_guid = PARTITION_SYSTEM_GUID;
static bool nocolor;
/**
* color() - set foreground color
*
* @color: foreground color
*/
static void color(u8 color)
{
if (!nocolor)
cout->set_attribute(cout, color | EFI_BACKGROUND_BLACK);
}
/**
* print() - print string
*
* @string: text
*/
static void print(u16 *string)
{
cout->output_string(cout, string);
}
/**
* cls() - clear screen
*/
static void cls(void)
{
if (nocolor)
print(u"\r\n");
else
cout->clear_screen(cout);
}
/**
* error() - print error string
*
* @string: error text
*/
static void error(u16 *string)
{
color(EFI_LIGHTRED);
print(string);
color(EFI_LIGHTBLUE);
}
/**
* efi_input_yn() - get answer to yes/no question
*
* Return:
* y or Y
* EFI_SUCCESS
* n or N
* EFI_ACCESS_DENIED
* ESC
* EFI_ABORTED
*/
static efi_status_t efi_input_yn(void)
{
struct efi_input_key key = {0};
efi_uintn_t index;
efi_status_t ret;
/* Drain the console input */
ret = cin->reset(cin, true);
for (;;) {
ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
if (ret != EFI_SUCCESS)
continue;
ret = cin->read_key_stroke(cin, &key);
if (ret != EFI_SUCCESS)
continue;
switch (key.scan_code) {
case 0x17: /* Escape */
return EFI_ABORTED;
default:
break;
}
/* Convert to lower case */
switch (key.unicode_char | 0x20) {
case 'y':
return EFI_SUCCESS;
case 'n':
return EFI_ACCESS_DENIED;
default:
break;
}
}
}
/**
* efi_input() - read string from console
*
* @buffer: input buffer
* @buffer_size: buffer size
* Return: status code
*/
static efi_status_t efi_input(u16 *buffer, efi_uintn_t buffer_size)
{
struct efi_input_key key = {0};
efi_uintn_t index;
efi_uintn_t pos = 0;
u16 outbuf[2] = u" ";
efi_status_t ret;
/* Drain the console input */
ret = cin->reset(cin, true);
*buffer = 0;
for (;;) {
ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
if (ret != EFI_SUCCESS)
continue;
ret = cin->read_key_stroke(cin, &key);
if (ret != EFI_SUCCESS)
continue;
switch (key.scan_code) {
case 0x17: /* Escape */
print(u"\r\nAborted\r\n");
return EFI_ABORTED;
default:
break;
}
switch (key.unicode_char) {
case 0x08: /* Backspace */
if (pos) {
buffer[pos--] = 0;
print(u"\b \b");
}
break;
case 0x0a: /* Linefeed */
case 0x0d: /* Carriage return */
print(u"\r\n");
return EFI_SUCCESS;
default:
break;
}
/* Ignore surrogate codes */
if (key.unicode_char >= 0xD800 && key.unicode_char <= 0xDBFF)
continue;
if (key.unicode_char >= 0x20 &&
pos < buffer_size - 1) {
*outbuf = key.unicode_char;
buffer[pos++] = key.unicode_char;
buffer[pos] = 0;
print(outbuf);
}
}
}
/**
* skip_whitespace() - skip over leading whitespace
*
* @pos: UTF-16 string
* Return: pointer to first non-whitespace
*/
static u16 *skip_whitespace(u16 *pos)
{
for (; *pos && *pos <= 0x20; ++pos)
;
return pos;
}
/**
* starts_with() - check if @string starts with @keyword
*
* @string: string to search for keyword
* @keyword: keyword to be searched
* Return: true fi @string starts with the keyword
*/
static bool starts_with(u16 *string, u16 *keyword)
{
if (!string || !keyword)
return NULL;
for (; *keyword; ++string, ++keyword) {
if (*string != *keyword)
return false;
}
return true;
}
/**
* open_file_system() - open simple file system protocol
*
* file_system: interface of the simple file system protocol
* Return: status code
*/
static efi_status_t
open_file_system(struct efi_simple_file_system_protocol **file_system)
{
struct efi_loaded_image *loaded_image;
efi_status_t ret;
efi_handle_t *handle_buffer = NULL;
efi_uintn_t count;
ret = bs->open_protocol(handle, &loaded_image_guid,
(void **)&loaded_image, NULL, NULL,
EFI_OPEN_PROTOCOL_GET_PROTOCOL);
if (ret != EFI_SUCCESS) {
error(u"Loaded image protocol not found\r\n");
return ret;
}
/* Open the simple file system protocol on the same partition */
ret = bs->open_protocol(loaded_image->device_handle,
&guid_simple_file_system_protocol,
(void **)file_system, NULL, NULL,
EFI_OPEN_PROTOCOL_GET_PROTOCOL);
if (ret == EFI_SUCCESS)
return ret;
/* Open the simple file system protocol on the UEFI system partition */
ret = bs->locate_handle_buffer(BY_PROTOCOL, &efi_system_partition_guid,
NULL, &count, &handle_buffer);
if (ret == EFI_SUCCESS && handle_buffer)
ret = bs->open_protocol(handle_buffer[0],
&guid_simple_file_system_protocol,
(void **)file_system, NULL, NULL,
EFI_OPEN_PROTOCOL_GET_PROTOCOL);
if (ret != EFI_SUCCESS)
error(u"Failed to open simple file system protocol\r\n");
if (handle)
bs->free_pool(handle_buffer);
return ret;
}
/**
* do_help() - print help
*/
static void do_help(void)
{
error(u"check - check SMBIOS table\r\n");
error(u"save <file> - save SMBIOS table to file\r\n");
error(u"exit - exit the shell\r\n");
}
/**
* 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 < systable->nr_tables; ++i) {
if (!memcmp(guid, &systable->tables[i].guid, 16))
return systable->tables[i].table;
}
return NULL;
}
/**
* checksum() - calculate checksum
*
* @buf: buffer to checksum
* @len: length of buffer
* Return: checksum
*/
u8 checksum(void *buf, int len)
{
u8 ret = 0;
for (u8 *ptr = buf; len; --len, ++ptr)
ret -= *ptr;
return ret;
}
/**
* do_check() - check SMBIOS table
*
* Return: status code
*/
efi_status_t do_check(void)
{
struct smbios3_entry *smbios3_anchor;
void *table, *table_end;
u32 len;
smbios3_anchor = get_config_table(&smbios3_guid);
if (smbios3_anchor) {
int r;
r = memcmp(smbios3_anchor->anchor, "_SM3_", 5);
if (r) {
error(u"Invalid anchor string\n");
return EFI_LOAD_ERROR;
}
print(u"Found SMBIOS 3 entry point\n");
if (smbios3_anchor->length != 0x18) {
error(u"Invalid anchor length\n");
return EFI_LOAD_ERROR;
}
if (checksum(smbios3_anchor, smbios3_anchor->length)) {
error(u"Invalid anchor checksum\n");
return EFI_LOAD_ERROR;
}
table = (void *)(uintptr_t)smbios3_anchor->struct_table_address;
len = smbios3_anchor->table_maximum_size;
} else {
struct smbios_entry *smbios_anchor;
int r;
smbios_anchor = get_config_table(&smbios_guid);
if (!smbios_anchor) {
error(u"No SMBIOS table\n");
return EFI_NOT_FOUND;
}
r = memcmp(smbios_anchor->anchor, "_SM_", 4);
if (r) {
error(u"Invalid anchor string\n");
return EFI_LOAD_ERROR;
}
print(u"Found SMBIOS 2.1 entry point\n");
if (smbios_anchor->length != 0x1f) {
error(u"Invalid anchor length\n");
return EFI_LOAD_ERROR;
}
if (checksum(smbios_anchor, smbios_anchor->length)) {
error(u"Invalid anchor checksum\n");
return EFI_LOAD_ERROR;
}
r = memcmp(smbios_anchor->intermediate_anchor, "_DMI_", 5);
if (r) {
error(u"Invalid intermediate anchor string\n");
return EFI_LOAD_ERROR;
}
if (checksum(&smbios_anchor->intermediate_anchor, 0xf)) {
error(u"Invalid intermediate anchor checksum\n");
return EFI_LOAD_ERROR;
}
table = (void *)(uintptr_t)smbios_anchor->struct_table_address;
len = smbios_anchor->struct_table_length;
}
table_end = (void *)((u8 *)table + len);
for (struct smbios_header *pos = table; ;) {
u8 *str = (u8 *)pos + pos->length;
if (!*str)
++str;
while (*str) {
for (; *str; ++str) {
if ((void *)str >= table_end) {
error(u"Structure table length exceeded\n");
return EFI_LOAD_ERROR;
}
}
++str;
}
++str;
if ((void *)str > table_end) {
error(u"Structure table length exceeded\n");
return EFI_LOAD_ERROR;
}
if (pos->type == 0x7f) /* End of table */
break;
pos = (struct smbios_header *)str;
}
return EFI_SUCCESS;
}
/**
* save_file() - save file to EFI system partition
*
* @filename: file name
* @buf: buffer to write
* @size: size of the buffer
*/
efi_status_t save_file(u16 *filename, void *buf, efi_uintn_t size)
{
efi_uintn_t ret;
struct efi_simple_file_system_protocol *file_system;
struct efi_file_handle *root, *file;
ret = open_file_system(&file_system);
if (ret != EFI_SUCCESS)
return ret;
/* Open volume */
ret = file_system->open_volume(file_system, &root);
if (ret != EFI_SUCCESS) {
error(u"Failed to open volume\r\n");
return ret;
}
/* Check if file already exists */
ret = root->open(root, &file, filename, EFI_FILE_MODE_READ, 0);
if (ret == EFI_SUCCESS) {
file->close(file);
print(u"Overwrite existing file (y/n)? ");
ret = efi_input_yn();
print(u"\r\n");
if (ret != EFI_SUCCESS) {
root->close(root);
error(u"Aborted by user\r\n");
bs->free_pool(buf);
return ret;
}
}
/* Create file */
ret = root->open(root, &file, filename,
EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE |
EFI_FILE_MODE_CREATE, EFI_FILE_ARCHIVE);
if (ret == EFI_SUCCESS) {
/* Write file */
ret = file->write(file, &size, buf);
if (ret != EFI_SUCCESS)
error(u"Failed to write file\r\n");
file->close(file);
} else {
error(u"Failed to open file\r\n");
}
root->close(root);
return ret;
}
/**
* do_save() - save SMBIOS table
*
* @filename: file name
* Return: status code
*/
static efi_status_t do_save(u16 *filename)
{
struct smbios3_entry *smbios3_anchor;
u8 *buf;
efi_uintn_t size;
efi_uintn_t ret;
ret = do_check();
if (ret != EFI_SUCCESS)
return ret;
smbios3_anchor = get_config_table(&smbios3_guid);
if (smbios3_anchor) {
size = 0x20 + smbios3_anchor->table_maximum_size;
ret = bs->allocate_pool(EFI_LOADER_DATA, size, (void **)&buf);
if (ret != EFI_SUCCESS) {
error(u"Out of memory\n");
return ret;
}
memset(buf, 0, size);
memcpy(buf, smbios3_anchor, smbios3_anchor->length);
memcpy(buf + 0x20,
(void *)(uintptr_t)smbios3_anchor->struct_table_address,
smbios3_anchor->table_maximum_size);
smbios3_anchor = (struct smbios3_entry *)buf;
smbios3_anchor->struct_table_address = 0x20;
smbios3_anchor->checksum +=
checksum(smbios3_anchor, smbios3_anchor->length);
} else {
struct smbios_entry *smbios_anchor;
smbios_anchor = get_config_table(&smbios_guid);
if (!smbios_anchor) {
/* Should not be reached after successful do_check() */
error(u"No SMBIOS table\n");
return EFI_NOT_FOUND;
}
size = 0x20 + smbios_anchor->struct_table_length;
ret = bs->allocate_pool(EFI_LOADER_DATA, size, (void **)&buf);
if (ret != EFI_SUCCESS) {
error(u"Out of memory\n");
return ret;
}
memset(buf, 0, size);
memcpy(buf, smbios_anchor, smbios_anchor->length);
memcpy(buf + 0x20,
(void *)(uintptr_t)smbios_anchor->struct_table_address,
smbios_anchor->struct_table_length);
smbios_anchor = (struct smbios_entry *)buf;
smbios_anchor->struct_table_address = 0x20;
smbios_anchor->intermediate_checksum +=
checksum(&smbios_anchor->intermediate_anchor, 0xf);
smbios_anchor->checksum +=
checksum(smbios_anchor, smbios_anchor->length);
}
filename = skip_whitespace(filename);
ret = save_file(filename, buf, size);
if (ret == EFI_SUCCESS) {
print(filename);
print(u" written\r\n");
}
bs->free_pool(buf);
return ret;
}
/**
* get_load_options() - get load options
*
* Return: load options or NULL
*/
static u16 *get_load_options(void)
{
efi_status_t ret;
struct efi_loaded_image *loaded_image;
ret = bs->open_protocol(handle, &loaded_image_guid,
(void **)&loaded_image, NULL, NULL,
EFI_OPEN_PROTOCOL_GET_PROTOCOL);
if (ret != EFI_SUCCESS) {
error(u"Loaded image protocol not found\r\n");
return NULL;
}
if (!loaded_image->load_options_size || !loaded_image->load_options)
return NULL;
return loaded_image->load_options;
}
/**
* command_loop - process user commands
*/
static void command_loop(void)
{
for (;;) {
u16 command[BUFFER_SIZE];
u16 *pos;
efi_uintn_t ret;
print(u"=> ");
ret = efi_input(command, sizeof(command));
if (ret == EFI_ABORTED)
break;
pos = skip_whitespace(command);
if (starts_with(pos, u"exit")) {
break;
} else if (starts_with(pos, u"check")) {
ret = do_check();
if (ret == EFI_SUCCESS)
print(u"OK\n");
} else if (starts_with(pos, u"save ")) {
do_save(pos + 5);
} else {
do_help();
}
}
}
/**
* efi_main() - entry point of the EFI application.
*
* @handle: handle of the loaded image
* @systab: system table
* Return: status code
*/
efi_status_t EFIAPI efi_main(efi_handle_t image_handle,
struct efi_system_table *systab)
{
u16 *load_options;
handle = image_handle;
systable = systab;
cerr = systable->std_err;
cout = systable->con_out;
cin = systable->con_in;
bs = systable->boottime;
load_options = get_load_options();
if (starts_with(load_options, u"nocolor"))
nocolor = true;
color(EFI_WHITE);
cls();
print(u"SMBIOS Dump\r\n===========\r\n\r\n");
color(EFI_LIGHTBLUE);
command_loop();
color(EFI_LIGHTGRAY);
cls();
return EFI_SUCCESS;
}