[PATCH 2/2] efi_loader: support boot from URI device path

AKASHI Takahiro takahiro.akashi at linaro.org
Thu Aug 24 04:32:24 CEST 2023


On Thu, Aug 24, 2023 at 11:24:31AM +0900, AKASHI Takahiro wrote:
> Kojima-san,
> 
> On Wed, Aug 23, 2023 at 05:37:20PM +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.
> 
> Is this behavior part of UEFI specification?
> Even so, it would be better to describe it in uefi.rst (or else),
> including URI usage.
> 
> > Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
> > ---
> >  lib/efi_loader/efi_bootmgr.c | 213 +++++++++++++++++++++++++++++++++++
> >  1 file changed, 213 insertions(+)
> > 
> > diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c
> > index a40762c74c..8b20f486f2 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 +172,209 @@ out:
> >  	return ret;
> >  }
> >  
> > +#if (IS_ENABLED(CONFIG_BLKMAP) && IS_ENABLED(CONFIG_CMD_WGET) && IS_ENABLED(CONFIG_CMD_DNS))
> > +/**
> > + * mount_image() - mount the image
> > + *
> > + * @lo_label	label of load option
> > + * @file_size	file size
> > + * @handle:	pointer to handle for newly installed image
> > + * Return:	status code
> > + */
> > +static efi_status_t mount_image(u16 *lo_label, int file_size,
> > +				efi_handle_t *handle)
> 
> I wonder why not adding "address" parameter to make this function
> more generic as Simon suggested.
> 
> > +{
> > +	int err;
> > +	efi_status_t ret;
> > +	char *label = NULL, *p;
> > +	lbaint_t blknum;
> > +	struct udevice *bm_dev;
> > +	efi_handle_t bm_handle;
> > +	struct udevice *blk, *partition;
> > +	struct efi_handler *handler;
> > +	struct efi_device_path *file_path;
> > +	struct efi_device_path *device_path;
> > +
> > +	label = efi_alloc(utf16_utf8_strlen(lo_label) + 1);
> > +	if (!label)
> > +		return EFI_OUT_OF_RESOURCES;
> > +
> > +	p = label;
> > +	utf16_utf8_strcpy(&p, lo_label);
> > +	err = blkmap_create(label, NULL);
> > +	if (err) {
> > +		log_err("failed to create blkmap\n");
> > +		ret = EFI_INVALID_PARAMETER;
> > +		goto out;
> > +	}
> > +	bm_dev = blkmap_from_label(label);
> > +	if (!bm_dev) {
> > +		log_err("\"%s\" is not the name of any known blkmap\n", label);
> > +		ret = EFI_INVALID_PARAMETER;
> > +		goto out;
> > +	}
> > +
> > +	blknum = file_size / 512; /* TODO: don't use literal value. */
> > +	err = blkmap_map_pmem(bm_dev, 0, blknum, image_load_addr);
> > +	if (err) {
> > +		log_err("Unable to map %#llx at block %d : %d\n",
> > +			(unsigned long long)image_load_addr, 0, err);
> > +		ret = EFI_INVALID_PARAMETER;
> > +		goto out;
> > +	}
> > +	log_info("Block %d+0x" LBAF " mapped to %#llx\n", 0, blknum,
> > +		 (unsigned long long)image_load_addr);
> > +
> > +	/* TODO: without calling this, partition devices are not binded. */
> > +	blk_list_part(UCLASS_BLKMAP);
> 
> I think that blkmap should provide a way to *probe* its child block
> device. In fact,
>         struct blkmap *bm = dev_get_plat(bm_dev);
>         device_probe(bm->blk);
> should work. (Not tested though)
> 
> > +
> > +	/*
> > +	 * Search the partition having EFI_SIMPLE_FILE_SYSTEM_PROTOCOL,
> > +	 * then try to load with the default boot file(e.g. EFI/BOOT/BOOTAA64.EFI).
> > +	 */
> > +	device_foreach_child(blk, bm_dev)
> 
> Does bm_dev have more than one block devices?
> 
> > +	{
> > +		device_foreach_child(partition, blk)
> > +		{
> > +			if (dev_tag_get_ptr(partition, DM_TAG_EFI,
> > +					    (void **)&bm_handle)) {
> > +				log_warning("DM_TAG_EFI not found\n");
> > +				continue;
> > +			}
> > +
> > +			ret = efi_search_protocol(
> > +				bm_handle,
> > +				&efi_simple_file_system_protocol_guid,
> > +				&handler);
> > +			if (ret != EFI_SUCCESS)
> > +				continue;
> > +
> > +			ret = efi_search_protocol(
> > +				bm_handle, &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;
> > +
> > +			file_path = expand_media_path(device_path);
> > +			ret = EFI_CALL(efi_load_image(true, efi_root, file_path,
> > +						      NULL, 0, handle));
> > +			efi_free_pool(file_path);
> > +			if (ret == EFI_SUCCESS)
> > +				goto out;
> > +		}
> > +	}
> 
> Another idea would be to create a new boot option (as a removable
> media) and to invoke it from bootmgr.

Never mind this comment.

-Takahiro Akashi

> 
> > +
> > +out:
> > +	efi_free_pool(label);
> > +
> > +	return ret;
> > +}
> > +
> > +/**
> > + * 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)
> > +{
> > +	efi_status_t ret;
> > +	int file_size, file_name_len;
> > +	char *s, *host_name, *file_name, *str_copy;
> > +
> > +	/*
> > +	 * Download file using wget.
> > +	 *
> > +	 * URI device path content is like http://www.example.com/sample/test.iso.
> > +	 * U-Boot wget takes the target uri in this format.
> > +	 *  "<http server ip>:<file path>"  e.g.) 192.168.1.1:/sample/test.iso
> > +	 * Need to resolve the http server ip address before starting wget.
> > +	 */
> > +
> > +	/* only support "http://" */
> > +	if (strncmp(uridp->uri, "http://", 7)) {
> > +		log_err("Error: uri must start with http://\n");
> > +		return EFI_INVALID_PARAMETER;
> > +	}
> > +
> > +	str_copy = strdup(uridp->uri);
> > +	if (!str_copy)
> > +		return EFI_OUT_OF_RESOURCES;
> > +	s = str_copy + strlen("http://");
> > +	host_name = strsep(&s, "/");
> > +	if (!s) {
> > +		log_err("Error: invalied uri, no file path\n");
> > +		ret = EFI_INVALID_PARAMETER;
> > +		goto out;
> > +	}
> > +	file_name = s;
> > +	net_dns_resolve = host_name;
> > +	net_dns_env_var = "httpserverip";
> > +	if (net_loop(DNS) < 0) {
> > +		log_err("Error: dns lookup of %s failed, check setup\n", net_dns_resolve);
> > +		ret = EFI_INVALID_PARAMETER;
> > +		goto out;
> > +	}
> > +	s = env_get("httpserverip");
> > +	if (!s) {
> > +		ret = EFI_INVALID_PARAMETER;
> > +		goto out;
> > +	}
> > +
> > +	/*
> > +	 * WGET requires that "net_boot_file_name" and "image_load_addr" global
> > +	 * variables are properly set in advance.
> > +	 */
> > +	strlcpy(net_boot_file_name, s, 1024);
> > +	strlcat(net_boot_file_name, ":/", 1024); /* append '/' which is removed by strsep() */
> > +	strlcat(net_boot_file_name, file_name, 1024);
> > +	s = env_get("loadaddr");
> > +	if (!s) {
> > +		log_err("Error: loadaddr is not set\n");
> > +		ret = EFI_INVALID_PARAMETER;
> > +		goto out;
> > +	}
> > +	image_load_addr = hextoul(s, NULL);
> > +
> > +	file_size = net_loop(WGET);
> > +	if (file_size < 0) {
> > +		log_err("Error: downloading file failed\n");
> > +		ret = EFI_INVALID_PARAMETER;
> > +		goto out;
> > +	}
> > +
> > +	/*
> > +	 * Identify file type by file extension.
> > +	 * If the file extension is ".iso" or ".img", mount it and boot with default file.
> > +	 * If the file is ".efi", load and start the downloaded file.
> > +	 */
> > +	file_name_len = strlen(net_boot_file_name);
> > +	if (!strncmp(&net_boot_file_name[file_name_len - 4], ".iso", 4) ||
> > +	    !strncmp(&net_boot_file_name[file_name_len - 4], ".img", 4)) {
> > +		ret = mount_image(lo_label, file_size, handle);
> > +	} else if (!strncmp(&net_boot_file_name[file_name_len - 4], ".efi", 4)) {
> > +		ret = efi_run_image((void *)image_load_addr, file_size);
> 
> Nak.
> try_load_from_uri_path() is called from try_load_entry().
> This function's purpose is solely to load an image.
> The execution should be triggered later.
> 
> -Takahiro Akashi
> 
> 
> > +	} else {
> > +		log_err("Error: file type is not supported\n");
> > +		ret = EFI_INVALID_PARAMETER;
> > +	}
> > +
> > +out:
> > +	free(str_copy);
> > +
> > +	return ret;
> > +}
> > +#endif
> > +
> >  /**
> >   * try_load_entry() - try to load image for boot option
> >   *
> > @@ -211,6 +418,12 @@ static efi_status_t try_load_entry(u16 n, efi_handle_t *handle,
> >  		if (EFI_DP_TYPE(lo.file_path, MEDIA_DEVICE, FILE_PATH)) {
> >  			/* file_path doesn't contain a device path */
> >  			ret = try_load_from_short_path(lo.file_path, handle);
> > +#if (IS_ENABLED(CONFIG_BLKMAP) && IS_ENABLED(CONFIG_CMD_WGET) && IS_ENABLED(CONFIG_CMD_DNS))
> > +		} else if (EFI_DP_TYPE(lo.file_path, MESSAGING_DEVICE, MSG_URI)) {
> > +			ret = try_load_from_uri_path(
> > +				(struct efi_device_path_uri *)lo.file_path,
> > +				lo.label, handle);
> > +#endif
> >  		} else {
> >  			file_path = expand_media_path(lo.file_path);
> >  			ret = EFI_CALL(efi_load_image(true, efi_root, file_path,
> > -- 
> > 2.34.1
> > 


More information about the U-Boot mailing list