[PATCH v11 6/9] bootmenu: add removable media entries
Takahiro Akashi
takahiro.akashi at linaro.org
Fri Aug 19 03:31:00 CEST 2022
On Wed, Aug 17, 2022 at 06:36:11PM +0900, Masahisa Kojima wrote:
> UEFI specification requires booting from removal media using
> a architecture-specific default image name such as BOOTAA64.EFI.
> This commit adds the removable media entries into bootmenu,
> so that user can select the removable media and boot with
> default image.
>
> The bootmenu automatically enumerates the possible bootable
> media devices supporting EFI_SIMPLE_FILE_SYSTEM_PROTOCOL,
> add it as new UEFI boot option(BOOT####) and update BootOrder
> variable. This automatically generated UEFI boot option
Should this feature belong to bootmenu command?
Under the current implementation, those boot options are
generated only by bootmenu, and so if eficonfig is invoked
prior to bootmenu, we won't see them (under "Change Boot Order").
I expect that the functionality be also provided in eficonfig
(or even as part of system initialization?).
-Takahiro Akashi
> has the dedicated guid in the optional_data to distinguish it from
> the UEFI boot option user adds manually. This optional_data is
> removed when the efi bootmgr loads the selected UEFI boot option.
>
> This commit also provides the BOOT#### variable maintenance feature.
> Depending on the system hardware setup, some devices
> may not exist at a later system boot, so bootmenu checks the
> available device in each bootmenu invocation and automatically
> removes the BOOT#### variable corrensponding to the non-existent
> media device.
>
> Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
> ---
> Changes in v11:
> - update delete_boot_option() parameter
>
> Changes in v10:
> - add function comment
> - devname dynamic allocation removes, allocate in stack
> - delete BOOT#### when updating BootOrder fails
>
> Changes in v9:
> - update efi_disk_get_device_name() parameter to pass efi_handle_t
> - add function comment
>
> Changes in v8:
> - function and structure prefix is changed to "eficonfig"
>
> Changes in v7:
> - rename prepare_media_device_entry() to generate_media_device_boot_option()
>
> Changes in v6:
> - optional_data size is changed to 16bytes
> - check the load option size before comparison
> - remove guid included in optional_data of auto generated
> entry when loading
>
> Changes in v5:
> - Return EFI_SUCCESS if there is no BootOrder defined
> - correctly handle the case if no removable device found
> - use guid to identify the automatically generated entry by bootmenu
>
> cmd/bootmenu.c | 106 +++++++++++++++++++++++++--
> cmd/eficonfig.c | 135 +++++++++++++++++++++++++++++++++++
> include/efi_loader.h | 20 ++++++
> lib/efi_loader/efi_bootmgr.c | 4 ++
> 4 files changed, 260 insertions(+), 5 deletions(-)
>
> diff --git a/cmd/bootmenu.c b/cmd/bootmenu.c
> index 704d36debe..04df41a0cb 100644
> --- a/cmd/bootmenu.c
> +++ b/cmd/bootmenu.c
> @@ -220,7 +220,93 @@ static int prepare_bootmenu_entry(struct bootmenu_data *menu,
> return 1;
> }
>
> -#if (CONFIG_IS_ENABLED(CMD_BOOTEFI_BOOTMGR))
> +#if (CONFIG_IS_ENABLED(CMD_BOOTEFI_BOOTMGR)) && (CONFIG_IS_ENABLED(CMD_EFICONFIG))
> +/**
> + * generate_media_device_boot_option() - generate the media device boot option
> + *
> + * This function enumerates all devices supporting EFI_SIMPLE_FILE_SYSTEM_PROTOCOL
> + * and generate the bootmenu entries.
> + * This function also provide the BOOT#### variable maintenance for
> + * the media device entries.
> + * - Automatically create the BOOT#### variable for the newly detected device,
> + * this BOOT#### variable is distinguished by the special GUID
> + * stored in the EFI_LOAD_OPTION.optional_data
> + * - If the device is not attached to the system, the associated BOOT#### variable
> + * is automatically deleted.
> + *
> + * Return: status code
> + */
> +static efi_status_t generate_media_device_boot_option(void)
> +{
> + u32 i;
> + efi_status_t ret;
> + efi_uintn_t count;
> + efi_handle_t *volume_handles = NULL;
> + struct eficonfig_media_boot_option *opt = NULL;
> +
> + ret = efi_locate_handle_buffer_int(BY_PROTOCOL, &efi_simple_file_system_protocol_guid,
> + NULL, &count, (efi_handle_t **)&volume_handles);
> + if (ret != EFI_SUCCESS)
> + return ret;
> +
> + opt = calloc(count, sizeof(struct eficonfig_media_boot_option));
> + if (!opt)
> + goto out;
> +
> + /* enumerate all devices supporting EFI_SIMPLE_FILE_SYSTEM_PROTOCOL */
> + ret = eficonfig_enumerate_boot_option(opt, volume_handles, count);
> + if (ret != EFI_SUCCESS)
> + goto out;
> +
> + /*
> + * System hardware configuration may vary depending on the user setup.
> + * The boot option is automatically added by the bootmenu.
> + * If the device is not attached to the system, the boot option needs
> + * to be deleted.
> + */
> + ret = eficonfig_delete_invalid_boot_option(opt, count);
> + if (ret != EFI_SUCCESS)
> + goto out;
> +
> + /* add non-existent boot option */
> + for (i = 0; i < count; i++) {
> + u32 boot_index;
> + u16 var_name[9];
> +
> + if (!opt[i].exist) {
> + ret = eficonfig_get_unused_bootoption(var_name, sizeof(var_name),
> + &boot_index);
> + if (ret != EFI_SUCCESS)
> + goto out;
> +
> + ret = efi_set_variable_int(var_name, &efi_global_variable_guid,
> + EFI_VARIABLE_NON_VOLATILE |
> + EFI_VARIABLE_BOOTSERVICE_ACCESS |
> + EFI_VARIABLE_RUNTIME_ACCESS,
> + opt[i].size, opt[i].lo, false);
> + if (ret != EFI_SUCCESS)
> + goto out;
> +
> + ret = eficonfig_append_bootorder(boot_index);
> + if (ret != EFI_SUCCESS) {
> + efi_set_variable_int(var_name, &efi_global_variable_guid,
> + 0, 0, NULL, false);
> + goto out;
> + }
> + }
> + }
> +
> +out:
> + if (opt) {
> + for (i = 0; i < count; i++)
> + free(opt[i].lo);
> + }
> + free(opt);
> + efi_free_pool(volume_handles);
> +
> + return ret;
> +}
> +
> /**
> * prepare_uefi_bootorder_entry() - generate the uefi bootmenu entries
> *
> @@ -340,11 +426,21 @@ static struct bootmenu_data *bootmenu_create(int delay)
> if (ret < 0)
> goto cleanup;
>
> -#if (CONFIG_IS_ENABLED(CMD_BOOTEFI_BOOTMGR))
> +#if (CONFIG_IS_ENABLED(CMD_BOOTEFI_BOOTMGR)) && (CONFIG_IS_ENABLED(CMD_EFICONFIG))
> if (i < MAX_COUNT - 1) {
> - ret = prepare_uefi_bootorder_entry(menu, &iter, &i);
> - if (ret < 0 && ret != -ENOENT)
> - goto cleanup;
> + efi_status_t efi_ret;
> +
> + /*
> + * UEFI specification requires booting from removal media using
> + * a architecture-specific default image name such as BOOTAA64.EFI.
> + */
> + efi_ret = generate_media_device_boot_option();
> + if (efi_ret != EFI_SUCCESS && efi_ret != EFI_NOT_FOUND)
> + goto cleanup;
> +
> + ret = prepare_uefi_bootorder_entry(menu, &iter, &i);
> + if (ret < 0 && ret != -ENOENT)
> + goto cleanup;
> }
> #endif
>
> diff --git a/cmd/eficonfig.c b/cmd/eficonfig.c
> index 6e39c0cd4d..c7f55c62fb 100644
> --- a/cmd/eficonfig.c
> +++ b/cmd/eficonfig.c
> @@ -2080,6 +2080,141 @@ static efi_status_t eficonfig_process_delete_boot_option(void *data)
> return ret;
> }
>
> +/**
> + * eficonfig_enumerate_boot_option() - enumerate the possible bootable media
> + *
> + * @opt: pointer to the media boot option structure
> + * @volume_handles: pointer to the efi handles
> + * @count: number of efi handle
> + * Return: status code
> + */
> +efi_status_t eficonfig_enumerate_boot_option(struct eficonfig_media_boot_option *opt,
> + efi_handle_t *volume_handles, efi_status_t count)
> +{
> + u32 i;
> + struct efi_handler *handler;
> + efi_status_t ret = EFI_SUCCESS;
> +
> + for (i = 0; i < count; i++) {
> + u16 *p;
> + u16 dev_name[BOOTMENU_DEVICE_NAME_MAX];
> + char *optional_data;
> + struct efi_load_option lo;
> + char buf[BOOTMENU_DEVICE_NAME_MAX];
> + struct efi_device_path *device_path;
> +
> + ret = efi_search_protocol(volume_handles[i], &efi_guid_device_path, &handler);
> + if (ret != EFI_SUCCESS)
> + continue;
> + ret = efi_protocol_open(handler, (void **)&device_path,
> + efi_root, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> + if (ret != EFI_SUCCESS)
> + continue;
> +
> + ret = efi_disk_get_device_name(volume_handles[i], buf, BOOTMENU_DEVICE_NAME_MAX);
> + if (ret != EFI_SUCCESS)
> + continue;
> +
> + p = dev_name;
> + utf8_utf16_strncpy(&p, buf, strlen(buf));
> +
> + lo.label = dev_name;
> + lo.attributes = LOAD_OPTION_ACTIVE;
> + lo.file_path = device_path;
> + lo.file_path_length = efi_dp_size(device_path) + sizeof(END);
> + /*
> + * Set the dedicated guid to optional_data, it is used to identify
> + * the boot option that automatically generated by the bootmenu.
> + * efi_serialize_load_option() expects optional_data is null-terminated
> + * utf8 string, so set the "1234567" string to allocate enough space
> + * to store guid, instead of realloc the load_option.
> + */
> + lo.optional_data = "1234567";
> + opt[i].size = efi_serialize_load_option(&lo, (u8 **)&opt[i].lo);
> + if (!opt[i].size) {
> + ret = EFI_OUT_OF_RESOURCES;
> + free(dev_name);
> + goto out;
> + }
> + /* set the guid */
> + optional_data = (char *)opt[i].lo + (opt[i].size - u16_strsize(u"1234567"));
> + memcpy(optional_data, &efi_guid_bootmenu_auto_generated, sizeof(efi_guid_t));
> + }
> +
> +out:
> + return ret;
> +}
> +
> +/**
> + * eficonfig_delete_invalid_boot_option() - delete non-existing boot option
> + *
> + * @opt: pointer to the media boot option structure
> + * @count: number of media boot option structure
> + * Return: status code
> + */
> +efi_status_t eficonfig_delete_invalid_boot_option(struct eficonfig_media_boot_option *opt,
> + efi_status_t count)
> +{
> + u16 *bootorder;
> + u32 i, j;
> + efi_status_t ret;
> + efi_uintn_t num, size, bootorder_size;
> + void *load_option;
> + struct efi_load_option lo;
> + u16 varname[] = u"Boot####";
> +
> + bootorder = efi_get_var(u"BootOrder", &efi_global_variable_guid, &bootorder_size);
> + if (!bootorder)
> + return EFI_SUCCESS; /* BootOrder is not defined, nothing to do */
> +
> + num = bootorder_size / sizeof(u16);
> + for (i = 0; i < num;) {
> + efi_uintn_t tmp;
> +
> + efi_create_indexed_name(varname, sizeof(varname),
> + "Boot", bootorder[i]);
> + load_option = efi_get_var(varname, &efi_global_variable_guid, &size);
> + if (!load_option)
> + goto next;
> +
> + tmp = size;
> + ret = efi_deserialize_load_option(&lo, load_option, &size);
> + if (ret != EFI_SUCCESS)
> + goto next;
> +
> + if (size >= sizeof(efi_guid_bootmenu_auto_generated)) {
> + if (guidcmp(lo.optional_data, &efi_guid_bootmenu_auto_generated) == 0) {
> + for (j = 0; j < count; j++) {
> + if (opt[j].size == tmp &&
> + memcmp(opt[j].lo, load_option, tmp) == 0) {
> + opt[j].exist = true;
> + break;
> + }
> + }
> +
> + if (j == count) {
> + ret = delete_boot_option(bootorder[i]);
> + if (ret != EFI_SUCCESS) {
> + free(load_option);
> + goto out;
> + }
> +
> + num--;
> + bootorder_size -= sizeof(u16);
> + free(load_option);
> + continue;
> + }
> + }
> + }
> +next:
> + free(load_option);
> + i++;
> + }
> +
> +out:
> + return ret;
> +}
> +
> /**
> * eficonfig_init() - do required initialization for eficonfig command
> *
> diff --git a/include/efi_loader.h b/include/efi_loader.h
> index 49e7d1e613..a5a0448fa0 100644
> --- a/include/efi_loader.h
> +++ b/include/efi_loader.h
> @@ -955,6 +955,22 @@ struct efi_signature_store {
> struct x509_certificate;
> struct pkcs7_message;
>
> +/**
> + * struct eficonfig_media_boot_option - boot option for (removable) media device
> + *
> + * This structure is used to enumerate possible boot option
> + *
> + * @lo: Serialized load option data
> + * @size: Size of serialized load option data
> + * @exist: Flag to indicate the load option already exists
> + * in Non-volatile load option
> + */
> +struct eficonfig_media_boot_option {
> + void *lo;
> + efi_uintn_t size;
> + bool exist;
> +};
> +
> bool efi_hash_regions(struct image_region *regs, int count,
> void **hash, const char *hash_algo, int *len);
> bool efi_signature_lookup_digest(struct efi_image_regions *regs,
> @@ -1104,6 +1120,10 @@ efi_status_t efi_console_get_u16_string
> efi_status_t eficonfig_get_unused_bootoption(u16 *buf,
> efi_uintn_t buf_size, u32 *index);
> efi_status_t eficonfig_append_bootorder(u16 index);
> +efi_status_t eficonfig_enumerate_boot_option(struct eficonfig_media_boot_option *opt,
> + efi_handle_t *volume_handles, efi_status_t count);
> +efi_status_t eficonfig_delete_invalid_boot_option(struct eficonfig_media_boot_option *opt,
> + efi_status_t count);
>
> efi_status_t efi_disk_get_device_name(const efi_handle_t handle, char *buf, int size);
>
> diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c
> index ede9116b3c..4b24b41047 100644
> --- a/lib/efi_loader/efi_bootmgr.c
> +++ b/lib/efi_loader/efi_bootmgr.c
> @@ -246,6 +246,10 @@ static efi_status_t try_load_entry(u16 n, efi_handle_t *handle,
> }
>
> /* Set load options */
> + if (size >= sizeof(efi_guid_t) &&
> + !guidcmp(lo.optional_data, &efi_guid_bootmenu_auto_generated))
> + size = 0;
> +
> if (size) {
> *load_options = malloc(size);
> if (!*load_options) {
> --
> 2.17.1
>
More information about the U-Boot
mailing list