Re: [PATCH v2 4/6] efi_loader: support boot from URI device path

[Ilias Apalodimas <ilias.apalodimas@linaro.org>]

Kojima-san

On Fri, Sep 01, 2023 at 07:25:40PM +0900, Masahisa Kojima wrote:
> This supports to boot from the URI device path.
> When user selects the URI device path, bootmgr downloads
> the file using wget into the address specified by loadaddr
> env variable.
> If the file is .iso or .img file, mount the image with blkmap
> then try to boot with the default file(e.g. EFI/BOOT/BOOTAA64.EFI).
> If the file is .efi file, load and start the downloaded file.
>
> Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
> ---
>  lib/efi_loader/efi_bootmgr.c | 197 +++++++++++++++++++++++++++++++++++
>  1 file changed, 197 insertions(+)
>
> diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c
> index a40762c74c..0e8d2ca9d1 100644
> --- a/lib/efi_loader/efi_bootmgr.c
> +++ b/lib/efi_loader/efi_bootmgr.c
> @@ -7,10 +7,14 @@
>
>  #define LOG_CATEGORY LOGC_EFI
>
> +#include <blk.h>
> +#include <blkmap.h>
>  #include <common.h>
>  #include <charset.h>
> +#include <dm.h>
>  #include <log.h>
>  #include <malloc.h>
> +#include <net.h>
>  #include <efi_default_filename.h>
>  #include <efi_loader.h>
>  #include <efi_variable.h>
> @@ -168,6 +172,193 @@ out:
>  	return ret;
>  }
>
> +#if (IS_ENABLED(CONFIG_BLKMAP) && IS_ENABLED(CONFIG_CMD_WGET) && IS_ENABLED(CONFIG_CMD_DNS))
> +/**
> + * mount_image() - mount the image with blkmap
> + *
> + * @lo_label	u16 label string of load option
> + * @image_addr:	image address
> + * @image_size	image size
> + * Return:	pointer to the UCLASS_BLK udevice, NULL if failed
> + */
> +static struct udevice *mount_image(u16 *lo_label, ulong image_addr, int image_size)
> +{
> +	int err;
> +	struct blkmap *bm;
> +	struct udevice *bm_dev;
> +	char *label = NULL, *p;
> +
> +	label = efi_alloc(utf16_utf8_strlen(lo_label) + 1);
> +	if (!label)
> +		return NULL;
> +
> +	p = label;
> +	utf16_utf8_strcpy(&p, lo_label);
> +	err = blkmap_create_ramdisk(label, image_addr, image_size, &bm_dev);
> +	if (err) {
> +		efi_free_pool(label);
> +		return NULL;
> +	}
> +	bm = dev_get_plat(bm_dev);
> +
> +	efi_free_pool(label);
> +
> +	return bm->blk;
> +}
> +
> +/**
> + * try_load_default_file() - try to load the default file
> + *
> + * Search the device having EFI_SIMPLE_FILE_SYSTEM_PROTOCOL,
> + * then try to load with the default boot file(e.g. EFI/BOOT/BOOTAA64.EFI).
> + *
> + * @dev			pointer to the UCLASS_BLK or UCLASS_PARTITION udevice
> + * @image_handle:	pointer to handle for newly installed image
> + * Return:		status code
> + */
> +static efi_status_t try_load_default_file(struct udevice *dev,
> +					  efi_handle_t *image_handle)
> +{
> +	efi_status_t ret;
> +	efi_handle_t bm_handle;
> +	struct efi_handler *handler;
> +	struct efi_device_path *file_path;
> +	struct efi_device_path *device_path;
> +
> +	if (dev_tag_get_ptr(dev, DM_TAG_EFI, (void **)&bm_handle)) {
> +		log_warning("DM_TAG_EFI not found\n");
> +		return EFI_INVALID_PARAMETER;
> +	}
> +
> +	ret = efi_search_protocol(bm_handle,
> +				  &efi_simple_file_system_protocol_guid, &handler);
> +	if (ret != EFI_SUCCESS)
> +		return ret;
> +
> +	ret = efi_search_protocol(bm_handle, &efi_guid_device_path, &handler);
> +	if (ret != EFI_SUCCESS)
> +		return ret;
> +
> +	ret = efi_protocol_open(handler, (void **)&device_path, efi_root, NULL,
> +				EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> +	if (ret != EFI_SUCCESS)
> +		return ret;
> +
> +	file_path = expand_media_path(device_path);
> +	ret = EFI_CALL(efi_load_image(true, efi_root, file_path, NULL, 0,
> +				      image_handle));
> +
> +	efi_free_pool(file_path);
> +
> +	return ret;
> +}

We need to decide what we want here.  There were recently some patches from
Raymond [0] which piggybacked on your earlier eficonfig work.  I think the
last patch of this series hasn't been merged due to a test failing, but we
should fix it.
That patch has a different approach.  Everytime a disk appears it will add
a boot option if the default filepath is found and that's how we fixed the
behaviour of efibootmgr to adhere to the EFI spec.  This patch is doing the
opposite, trying to detect the BOOTAA64.EFI etc on the fly.  I think I
prefer the approach you have here, but we should end up with one solution
to solve both.

> +
> +/**
> + * load_default_file_from_blk_dev() - load the default file
> + *
> + * @blk		pointer to the UCLASS_BLK udevice
> + * @handle:	pointer to handle for newly installed image
> + * Return:	status code
> + */
> +static efi_status_t load_default_file_from_blk_dev(struct udevice *blk,
> +						   efi_handle_t *handle)
> +{
> +	efi_status_t ret;
> +	struct udevice *partition;
> +
> +	/* image that has no partition table but a file system */
> +	ret = try_load_default_file(blk, handle);
> +	if (ret == EFI_SUCCESS)
> +		return ret;
> +
> +	/* try the partitions */
> +	device_foreach_child(partition, blk) {
> +		enum uclass_id id;
> +
> +		id = device_get_uclass_id(partition);
> +		if (id != UCLASS_PARTITION)
> +			continue;
> +
> +		ret = try_load_default_file(partition, handle);
> +		if (ret == EFI_SUCCESS)
> +			return ret;
> +	}
> +
> +	return EFI_NOT_FOUND;
> +}
> +
> +/**
> + * try_load_from_uri_path() - Handle the URI device path
> + *
> + * @uridp:	uri device path
> + * @lo_label	label of load option
> + * @handle:	pointer to handle for newly installed image
> + * Return:	status code
> + */
> +static efi_status_t try_load_from_uri_path(struct efi_device_path_uri *uridp,
> +					   u16 *lo_label,
> +					   efi_handle_t *handle)
> +{
> +	char *s;
> +	int uri_len;
> +	int image_size;
> +	efi_status_t ret;
> +	ulong image_addr;
> +
> +	s = env_get("loadaddr");
> +	if (!s) {
> +		log_err("Error: loadaddr is not set\n");
> +		return EFI_INVALID_PARAMETER;
> +	}
> +	image_addr = hextoul(s, NULL);
> +	image_size = wget_with_dns(image_addr, uridp->uri);
> +	if (image_size < 0)
> +		return EFI_INVALID_PARAMETER;
> +
> +	/*
> +	 * If the file extension is ".iso" or ".img", mount it and try to load
> +	 * the default file.

Don't we have a better way to validate isos and efi apps instead of
the extension?  The efi is checked against a valid PE/COFF image so I guess
we'll really on the mount to fail for isos?

> +	 * If the file is ".efi" and PE-COFF image, load the downloaded file.
> +	 */
> +	uri_len = strlen(uridp->uri); /* todo: directly use uridp->uri */
> +	if (!strncmp(&uridp->uri[uri_len - 4], ".iso", 4) ||
> +	    !strncmp(&uridp->uri[uri_len - 4], ".img", 4)) {
> +		struct udevice *blk;
> +
> +		blk = mount_image(lo_label, image_addr, image_size);
> +		if (!blk)
> +			return EFI_INVALID_PARAMETER;
> +
> +		ret = load_default_file_from_blk_dev(blk, handle);
> +	} else if (!strncmp(&uridp->uri[uri_len - 4], ".efi", 4)) {
> +		efi_handle_t mem_handle = NULL;
> +		struct efi_device_path *file_path = NULL;
> +
> +		ret = efi_check_pe((void *)image_addr, image_size, NULL);
> +		if (ret != EFI_SUCCESS) {
> +			log_err("Error: downloaded image is not a PE-COFF image\n");
> +			return EFI_INVALID_PARAMETER;
> +		}
> +
> +		file_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE,
> +					    (uintptr_t)image_addr, image_size);
> +		ret = efi_install_multiple_protocol_interfaces(
> +			&mem_handle, &efi_guid_device_path, file_path, NULL);
> +		if (ret != EFI_SUCCESS)
> +			return EFI_INVALID_PARAMETER;
> +
> +		ret = EFI_CALL(efi_load_image(false, efi_root, file_path,
> +					      (void *)image_addr, image_size,

[0] https://lore.kernel.org/u-boot/20230619212303.128288-1-raymond.mao@linaro.org/

Thanks
/Ilias