Introduce a new helper efi_capsule_update_info_gen_ids() which takes
several strings to identify the currently running board as well as a
platform specific salt UUID and uses this data to populate the capsule
update fw images image_type_id field. This allows for determinstic UUIDs
to be used that can scale to a large number of different boards and
board variants without the need to maintain a big list.
Generating capsule updates can be done using the same namespace, soc,
model, compatible, and fw_image name strings.
This is behind an additional config option as it depends on V5 UUIDs and
the SHA1 implementation.
Signed-off-by: Caleb Connolly <caleb.conno...@linaro.org>
---
include/efi_loader.h | 28 ++++++++++++++++++++++++++++
lib/efi_loader/Kconfig | 14 ++++++++++++++
lib/efi_loader/efi_capsule.c | 33 +++++++++++++++++++++++++++++++++
3 files changed, 75 insertions(+)
diff --git a/include/efi_loader.h b/include/efi_loader.h
index 69442f4e58de..7d6b6ff83229 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -1125,8 +1125,36 @@ struct efi_capsule_update_info {
};
extern struct efi_capsule_update_info update_info;
+#if CONFIG_IS_ENABLED(EFI_CAPSULE_DYNAMIC_UUIDS)
+/**
+ * efi_capsule_update_info_gen_ids - Generate image_type_id UUIDs
+ * for all firmware images based on a platform namespace UUID.
+ *
+ * @namespace: The arch/platform specific namespace salt. This should be
+ * hardcoded per platform and replaced by vendors.
+ * @soc: A string identifying the SoC used on this board.
+ * @model: The model string for the board.
+ * @compatible: The most specific (first) root compatible string.
+ *
+ * This can be called by board code to populate the image_type_id
+ * UUID fields deterministically based on the board's model. Allowing
+ * many boards to be supported without the need for a large hardcoded
+ * array of fw images. This works using v5 UUIDs.
+ */
+int efi_capsule_update_info_gen_ids(efi_guid_t *namespace, const char *soc,
+ const char *model,
+ const char *compatible);
+#else
+static inline int efi_capsule_update_info_gen_ids(efi_guid_t *namespace, const
char *soc,
+ const char *model,
+ const char *compatible)
+{
+ return -ENOSYS;
+}
+#endif
+
/**
* Install the ESRT system table.
*
* Return: status code
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
index 430bb7f0f7dc..dd8fc1b08812 100644
--- a/lib/efi_loader/Kconfig
+++ b/lib/efi_loader/Kconfig
@@ -235,8 +235,22 @@ config EFI_CAPSULE_ON_DISK_EARLY
If this option is enabled, capsules will be enforced to be
executed as part of U-Boot initialisation so that they will
surely take place whatever is set to distro_bootcmd.
+config EFI_CAPSULE_DYNAMIC_UUIDS
+ bool "Dynamic UUIDs for capsules"
+ depends on EFI_HAVE_CAPSULE_SUPPORT
+ select UUID_GEN_V5
+ help
+ Select this option if you want to use dynamically generated v5
+ UUIDs for your board. To make use of this feature, your board
+ code should call efi_capsule_update_info_gen_ids() with a seed
+ UUID to generate the image_type_id field for each fw_image.
+
+ The CapsuleUpdate payloads are expected to generate matching UUIDs
+ using the same scheme.
+
+
config EFI_CAPSULE_FIRMWARE
bool
config EFI_CAPSULE_FIRMWARE_MANAGEMENT
diff --git a/lib/efi_loader/efi_capsule.c b/lib/efi_loader/efi_capsule.c
index de0d49ebebda..9ef67d1b4405 100644
--- a/lib/efi_loader/efi_capsule.c
+++ b/lib/efi_loader/efi_capsule.c
@@ -19,8 +19,9 @@
#include <mapmem.h>
#include <sort.h>
#include <sysreset.h>
#include <asm/global_data.h>
+#include <uuid.h>
#include <crypto/pkcs7.h>
#include <crypto/pkcs7_parser.h>
#include <linux/err.h>
@@ -403,8 +404,40 @@ out:
return status;
}
#endif /* CONFIG_EFI_CAPSULE_AUTHENTICATE */
+#if CONFIG_IS_ENABLED(EFI_CAPSULE_DYNAMIC_UUIDS)
+int efi_capsule_update_info_gen_ids(efi_guid_t *namespace, const char *soc,
const char *model, const char *compatible)
+{
+ int i;
+
+ if (!soc || !model || !compatible) {
+ log_err("%s: soc, model, or compatible not defined\n",
__func__);
+ return -EINVAL;
+ }
+
+ if (!update_info.num_images) {
+ log_err("%s: no fw_images, make sure update_info.num_images is
set\n", __func__);
+ return -ENODATA;
+ }
+
+ for (i = 0; i < update_info.num_images; i++) {
+ gen_uuid_v5((struct uuid*)namespace,
+ (struct uuid *)&update_info.images[i].image_type_id,
+ soc, strlen(soc),
+ model, strlen(model),
+ compatible, strlen(compatible),
+ update_info.images[i].fw_name,
u16_strlen(update_info.images[i].fw_name),
+ NULL);
+
+ log_debug("Image %ls generated UUID %pUs\n",
update_info.images[i].fw_name,
+ &update_info.images[i].image_type_id);
+ }
+
+ return 0;
+}
+#endif
+
static __maybe_unused bool fwu_empty_capsule(struct efi_capsule_header
*capsule)
{
return !guidcmp(&capsule->capsule_guid,
&fwu_guid_os_request_fw_revert) ||
--
2.44.0
