efi_loader: bootmgr: add load option helper functions

In this patch, helper functions for an load option variable (BootXXXX)
are added:
* efi_deserialize_load_option(): parse a string into load_option data
			(renamed from parse_load_option and exported)
* efi_serialize_load_option(): convert load_option data into a string

Those functions will be used to implement efishell command.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
AKASHI Takahiro 2018-11-05 18:06:41 +09:00 committed by Alexander Graf
parent 2419b161cc
commit 1a82b3413c
2 changed files with 83 additions and 33 deletions

View file

@ -518,6 +518,29 @@ efi_status_t EFIAPI efi_set_variable(u16 *variable_name, efi_guid_t *vendor,
u32 attributes, efi_uintn_t data_size,
void *data);
/*
* See section 3.1.3 in the v2.7 UEFI spec for more details on
* the layout of EFI_LOAD_OPTION. In short it is:
*
* typedef struct _EFI_LOAD_OPTION {
* UINT32 Attributes;
* UINT16 FilePathListLength;
* // CHAR16 Description[]; <-- variable length, NULL terminated
* // EFI_DEVICE_PATH_PROTOCOL FilePathList[];
* <-- FilePathListLength bytes
* // UINT8 OptionalData[];
* } EFI_LOAD_OPTION;
*/
struct efi_load_option {
u32 attributes;
u16 file_path_length;
u16 *label;
struct efi_device_path *file_path;
u8 *optional_data;
};
void efi_deserialize_load_option(struct efi_load_option *lo, u8 *data);
unsigned long efi_serialize_load_option(struct efi_load_option *lo, u8 **data);
void *efi_bootmgr_load(struct efi_device_path **device_path,
struct efi_device_path **file_path);

View file

@ -9,6 +9,7 @@
#include <charset.h>
#include <malloc.h>
#include <efi_loader.h>
#include <asm/unaligned.h>
static const struct efi_boot_services *bs;
static const struct efi_runtime_services *rs;
@ -30,42 +31,68 @@ static const struct efi_runtime_services *rs;
*/
/*
* See section 3.1.3 in the v2.7 UEFI spec for more details on
* the layout of EFI_LOAD_OPTION. In short it is:
*
* typedef struct _EFI_LOAD_OPTION {
* UINT32 Attributes;
* UINT16 FilePathListLength;
* // CHAR16 Description[]; <-- variable length, NULL terminated
* // EFI_DEVICE_PATH_PROTOCOL FilePathList[]; <-- FilePathListLength bytes
* // UINT8 OptionalData[];
* } EFI_LOAD_OPTION;
*/
struct load_option {
u32 attributes;
u16 file_path_length;
u16 *label;
struct efi_device_path *file_path;
u8 *optional_data;
};
/* parse an EFI_LOAD_OPTION, as described above */
static void parse_load_option(struct load_option *lo, void *ptr)
/* Parse serialized data and transform it into efi_load_option structure */
void efi_deserialize_load_option(struct efi_load_option *lo, u8 *data)
{
lo->attributes = *(u32 *)ptr;
ptr += sizeof(u32);
lo->attributes = get_unaligned_le32(data);
data += sizeof(u32);
lo->file_path_length = *(u16 *)ptr;
ptr += sizeof(u16);
lo->file_path_length = get_unaligned_le16(data);
data += sizeof(u16);
lo->label = ptr;
ptr += (u16_strlen(lo->label) + 1) * 2;
/* FIXME */
lo->label = (u16 *)data;
data += (u16_strlen(lo->label) + 1) * sizeof(u16);
lo->file_path = ptr;
ptr += lo->file_path_length;
/* FIXME */
lo->file_path = (struct efi_device_path *)data;
data += lo->file_path_length;
lo->optional_data = ptr;
lo->optional_data = data;
}
/*
* Serialize efi_load_option structure into byte stream for BootXXXX.
* Return a size of allocated data.
*/
unsigned long efi_serialize_load_option(struct efi_load_option *lo, u8 **data)
{
unsigned long label_len, option_len;
unsigned long size;
u8 *p;
label_len = (u16_strlen(lo->label) + 1) * sizeof(u16);
option_len = strlen((char *)lo->optional_data);
/* total size */
size = sizeof(lo->attributes);
size += sizeof(lo->file_path_length);
size += label_len;
size += lo->file_path_length;
size += option_len + 1;
p = malloc(size);
if (!p)
return 0;
/* copy data */
*data = p;
memcpy(p, &lo->attributes, sizeof(lo->attributes));
p += sizeof(lo->attributes);
memcpy(p, &lo->file_path_length, sizeof(lo->file_path_length));
p += sizeof(lo->file_path_length);
memcpy(p, lo->label, label_len);
p += label_len;
memcpy(p, lo->file_path, lo->file_path_length);
p += lo->file_path_length;
memcpy(p, lo->optional_data, option_len);
p += option_len;
*(char *)p = '\0';
return size;
}
/* free() the result */
@ -100,7 +127,7 @@ static void *get_var(u16 *name, const efi_guid_t *vendor,
static void *try_load_entry(uint16_t n, struct efi_device_path **device_path,
struct efi_device_path **file_path)
{
struct load_option lo;
struct efi_load_option lo;
u16 varname[] = L"Boot0000";
u16 hexmap[] = L"0123456789ABCDEF";
void *load_option, *image = NULL;
@ -115,7 +142,7 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path,
if (!load_option)
return NULL;
parse_load_option(&lo, load_option);
efi_deserialize_load_option(&lo, load_option);
if (lo.attributes & LOAD_OPTION_ACTIVE) {
efi_status_t ret;