tools: mkeficapsule: support generating dynamic GUIDs
Add support for generating GUIDs that match those generated internally
by U-Boot for capsule update fw_images when using dynamic UUIDs.
Dynamic UUIDs in U-Boot work by taking a namespace UUID and hashing it
with the board compatible and fw_image name. This feature just provides
a way to determine the UUIDs for a particular board without having to
actually boot U-Boot on it.
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
diff --git a/doc/mkeficapsule.1 b/doc/mkeficapsule.1
index c3d0f21..a5545f7 100644
--- a/doc/mkeficapsule.1
+++ b/doc/mkeficapsule.1
@@ -10,6 +10,9 @@
.B mkeficapsule
.RI [ options ] " " [ image-blob ] " " capsule-file
+.B mkeficapsule
+.RI guidgen " " [ GUID ] " " DTB " " IMAGE_NAME...
+
.SH "DESCRIPTION"
The
.B mkeficapsule
@@ -42,6 +45,10 @@
This type of image file can be generated by
.BR mkimage .
+mkeficapsule can also be used to simulate the dynamic GUID generation used to
+identify firmware images in capsule updates by providing the namespace guid, dtb
+for the board, and a list of firmware images.
+
.SH "OPTIONS"
.TP
@@ -117,6 +124,22 @@
.B "-d\fR,\fB --dump_sig"
Dump signature data into *.p7 file
+.SH "GUIDGEN OPTIONS"
+
+.TP
+.B "[GUID]"
+The namespace/salt GUID, by default this is EFI_CAPSULE_NAMESPACE_GUID.
+The format is:
+ xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+
+.TP
+.B DTB
+The device tree blob file for the board.
+
+.TP
+.B IMAGE_NAME...
+The names of the firmware images to generate GUIDs for.
+
.PP
.SH FILES
.TP
diff --git a/tools/mkeficapsule.c b/tools/mkeficapsule.c
index ede9de2..49f5b78 100644
--- a/tools/mkeficapsule.c
+++ b/tools/mkeficapsule.c
@@ -22,10 +22,14 @@
#include <gnutls/abstract.h>
#include <version.h>
+#include <libfdt.h>
#include <u-boot/uuid.h>
#include "eficapsule.h"
+// Matches CONFIG_EFI_CAPSULE_NAMESPACE_GUID
+#define DEFAULT_NAMESPACE_GUID "8c9f137e-91dc-427b-b2d6-b420faebaf2a"
+
static const char *tool_name = "mkeficapsule";
efi_guid_t efi_guid_fm_capsule = EFI_FIRMWARE_MANAGEMENT_CAPSULE_ID_GUID;
@@ -56,9 +60,20 @@
{NULL, 0, NULL, 0},
};
+static void print_usage_guidgen(void)
+{
+ fprintf(stderr, "%s guidgen [GUID] DTB IMAGE_NAME...\n"
+ "Options:\n"
+
-static void print_usage(void)
+ "\tGUID Namespace GUID (default: %s)\n"
+ "\tDTB Device Tree Blob\n"
+ "\tIMAGE_NAME... One or more names of fw_images to generate GUIDs for\n",
+ tool_name, DEFAULT_NAMESPACE_GUID);
+}
+
+static void print_usage_mkeficapsule(void)
{
- fprintf(stderr, "Usage: %s [options] <image blob> <output file>\n"
+ fprintf(stderr, "Usage:\n\n%s [options] <image blob> <output file>\n"
"Options:\n"
"\t-g, --guid <guid string> guid for image blob type\n"
@@ -74,8 +89,9 @@
"\t-o, --capoemflag Capsule OEM Flag, an integer between 0x0000 and 0xffff\n"
"\t-D, --dump-capsule dump the contents of the capsule headers\n"
"\t-V, --version show version number\n"
- "\t-h, --help print a help message\n",
+ "\t-h, --help print a help message\n\n",
tool_name);
+ print_usage_guidgen();
}
/**
@@ -818,8 +834,131 @@
capsule_file);
exit(EXIT_FAILURE);
}
+}
+
+static struct fdt_header *load_dtb(const char *path)
+{
+ struct fdt_header *dtb;
+ ssize_t dtb_size;
+ FILE *f;
+
+ /* Open and parse DTB */
+ f = fopen(path, "r");
+ if (!f) {
+ fprintf(stderr, "Cannot open %s\n", path);
+ return NULL;
+ }
+
+ if (fseek(f, 0, SEEK_END)) {
+ fprintf(stderr, "Cannot seek to the end of %s: %s\n",
+ path, strerror(errno));
+ return NULL;
+ }
+
+ dtb_size = ftell(f);
+ if (dtb_size < 0) {
+ fprintf(stderr, "Cannot ftell %s: %s\n",
+ path, strerror(errno));
+ return NULL;
+ }
+
+ fseek(f, 0, SEEK_SET);
+
+ dtb = malloc(dtb_size);
+ if (!dtb) {
+ fprintf(stderr, "Can't allocated %ld\n", dtb_size);
+ return NULL;
+ }
+
+ if (fread(dtb, dtb_size, 1, f) != 1) {
+ fprintf(stderr, "Can't read %ld bytes from %s\n",
+ dtb_size, path);
+ free(dtb);
+ return NULL;
+ }
+
+ fclose(f);
+
+ return dtb;
}
+#define MAX_IMAGE_NAME_LEN 128
+static int genguid(int argc, char **argv)
+{
+ int idx = 2, ret;
+ unsigned char namespace[16];
+ struct efi_guid image_type_id;
+ const char *dtb_path;
+ struct fdt_header *dtb;
+ const char *compatible;
+ int compatlen, namelen;
+ uint16_t fw_image[MAX_IMAGE_NAME_LEN];
+
+ if (argc < 2) {
+ fprintf(stderr, "Usage: ");
+ print_usage_guidgen();
+ return -1;
+ }
+
+ if (uuid_str_to_bin(argv[1], namespace, UUID_STR_FORMAT_GUID)) {
+ uuid_str_to_bin(DEFAULT_NAMESPACE_GUID, namespace, UUID_STR_FORMAT_GUID);
+ dtb_path = argv[1];
+ } else {
+ dtb_path = argv[2];
+ idx = 3;
+ }
+
+ if (idx == argc) {
+ fprintf(stderr, "Usage: ");
+ print_usage_guidgen();
+ return -1;
+ }
+
+ dtb = load_dtb(dtb_path);
+ if (!dtb)
+ return -1;
+
+ ret = fdt_check_header(dtb);
+ if (ret) {
+ fprintf(stderr, "Invalid DTB header: %d\n", ret);
+ return -1;
+ }
+
+ compatible = fdt_getprop(dtb, 0, "compatible", &compatlen);
+ if (!compatible) {
+ fprintf(stderr, "No compatible string found in DTB\n");
+ return -1;
+ }
+ if (strnlen(compatible, compatlen) >= compatlen) {
+ fprintf(stderr, "Compatible string not null-terminated\n");
+ return -1;
+ }
+
+ printf("Generating GUIDs for %s with namespace %s:\n",
+ compatible, DEFAULT_NAMESPACE_GUID);
+ for (; idx < argc; idx++) {
+ memset(fw_image, 0, sizeof(fw_image));
+ namelen = strlen(argv[idx]);
+ if (namelen > MAX_IMAGE_NAME_LEN) {
+ fprintf(stderr, "Image name too long: %s\n", argv[idx]);
+ return -1;
+ }
+
+ for (int i = 0; i < namelen; i++)
+ fw_image[i] = (uint16_t)argv[idx][i];
+
+ gen_v5_guid((struct uuid *)&namespace, &image_type_id,
+ compatible, strlen(compatible),
+ fw_image, namelen * sizeof(uint16_t),
+ NULL);
+
+ printf("%s: ", argv[idx]);
+ print_guid(&image_type_id);
+ }
+
+ return 0;
+}
+
/**
* main - main entry function of mkeficapsule
* @argc: Number of arguments
@@ -844,6 +983,13 @@
int c, idx;
struct fmp_payload_header_params fmp_ph_params = { 0 };
+ /* Generate dynamic GUIDs */
+ if (argc > 1 && !strcmp(argv[1], "guidgen")) {
+ if (genguid(argc - 1, argv + 1))
+ exit(EXIT_FAILURE);
+ exit(EXIT_SUCCESS);
+ }
+
guid = NULL;
index = 0;
instance = 0;
@@ -935,7 +1081,7 @@
printf("mkeficapsule version %s\n", PLAIN_VERSION);
exit(EXIT_SUCCESS);
default:
- print_usage();
+ print_usage_mkeficapsule();
exit(EXIT_FAILURE);
}
}
@@ -958,7 +1104,7 @@
((argc != optind + 1) ||
((capsule_type == CAPSULE_ACCEPT) && !guid) ||
((capsule_type == CAPSULE_REVERT) && guid)))) {
- print_usage();
+ print_usage_mkeficapsule();
exit(EXIT_FAILURE);
}