[PATCH v2 6/7] tools: add genguid tool

[Caleb Connolly]

Add a tool that can generate GUIDs that match those generated internally
by U-Boot for capsule update fw_images.

Dynamic UUIDs in U-Boot work by taking a namespace UUID and hashing it
with the board model, compatible, and fw_image name.

This tool accepts the same inputs and will produce the same GUID as
U-Boot would at runtime.

Signed-off-by: Caleb Connolly <caleb.connolly at linaro.org>
---
 tools/Makefile  |   3 ++
 tools/genguid.c | 154 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 157 insertions(+)

diff --git a/tools/Makefile b/tools/Makefile
index 6a4280e3668f..7db7723793d5 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -253,8 +253,11 @@ HOSTLDLIBS_mkeficapsule += \
 HOSTLDLIBS_mkeficapsule += \
 	$(shell pkg-config --libs uuid 2> /dev/null || echo "-luuid")
 hostprogs-$(CONFIG_TOOLS_MKEFICAPSULE) += mkeficapsule
 
+genguid-objs := generated/lib/uuid.o generated/lib/sha1.o genguid.o
+hostprogs-$(CONFIG_TOOLS_MKEFICAPSULE) += genguid
+
 mkfwumdata-objs := mkfwumdata.o generated/lib/crc32.o
 HOSTLDLIBS_mkfwumdata += -luuid
 hostprogs-$(CONFIG_TOOLS_MKFWUMDATA) += mkfwumdata
 
diff --git a/tools/genguid.c b/tools/genguid.c
new file mode 100644
index 000000000000..dbac65d42623
--- /dev/null
+++ b/tools/genguid.c
@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2024 Linaro Ltd.
+ *   Author: Caleb Connolly
+ */
+
+#include <getopt.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <linux/types.h>
+
+#include <uuid.h>
+
+static struct option options[] = {
+	{"dtb", required_argument, NULL, 'd'},
+	{"compat", required_argument, NULL, 'c'},
+	{"help", no_argument, NULL, 'h'},
+	{"verbose", no_argument, NULL, 'v'},
+	{"json", no_argument, NULL, 'j'},
+	{NULL, 0, NULL, 0},
+};
+
+static void usage(const char *progname)
+{
+	fprintf(stderr, "Usage: %s GUID [-v] -c COMPAT NAME...\n", progname);
+	fprintf(stderr,
+		"Generate a v5 GUID for one of more U-Boot fw_images the same way U-Boot does at runtime.\n");
+	fprintf(stderr,
+		"\nOptions:\n"
+		"  GUID                     namespace/salt GUID in 8-4-4-4-12 format\n"
+		"  -h, --help               display this help and exit\n"
+		"  -c, --compat=COMPAT      first compatible property in the board devicetree\n"
+		"  -v, --verbose            print debug messages\n"
+		"  -j, --json               output in JSON format\n"
+		"  NAME...                  one or more names of fw_images to generate GUIDs for\n"
+	);
+	fprintf(stderr, "\nExample:\n");
+	fprintf(stderr, "  %s 2a5aa852-b856-4d97-baa9-5c5f4421551f \\\n"
+			"\t-c \"qcom,qrb4210-rb2\" \\\n"
+			"\tQUALCOMM-UBOOT\n", progname);
+}
+
+size_t u16_strsize(const uint16_t *in)
+{
+	size_t i = 0, count = UINT16_MAX;
+
+	while (count-- && in[i])
+		i++;
+
+	return (i + 1) * sizeof(uint16_t);
+}
+
+int main(int argc, char **argv)
+{
+	struct uuid namespace;
+	char *namespace_str;
+	char uuid_str[37];
+	char **image_uuids;
+	char *compatible = NULL;
+	uint16_t **images_u16;
+	char **images;
+	int c, n_images;
+	bool debug = false, json = false;
+
+	if (argc < 2) {
+		usage(argv[0]);
+		return 1;
+	}
+
+	namespace_str = argv[1];
+
+	/* The first arg is the GUID so skip it */
+	while ((c = getopt_long(argc, argv, "c:hvj", options, NULL)) != -1) {
+		switch (c) {
+		case 'c':
+			compatible = strdup(optarg);
+			break;
+		case 'h':
+			usage(argv[0]);
+			return 0;
+		case 'v':
+			debug = true;
+			break;
+		case 'j':
+			json = true;
+			break;
+		default:
+			usage(argv[0]);
+			return 1;
+		}
+	}
+
+	if (!compatible) {
+		fprintf(stderr, "ERROR: Please specify the compatible property.\n\n");
+		usage(argv[0]);
+		return 1;
+	}
+
+	if (uuid_str_to_bin(namespace_str, (unsigned char *)&namespace, UUID_STR_FORMAT_GUID)) {
+		fprintf(stderr, "ERROR: Check that your UUID is formatted correctly.\n");
+		exit(EXIT_FAILURE);
+	}
+
+	/* This is probably not the best way to convert a string to a "u16" string */
+	n_images = argc - optind - 1;
+	images = argv + optind + 1;
+	images_u16 = calloc(n_images, sizeof(char *));
+	for (int i = 0; i < n_images; i++) {
+		images_u16[i] = calloc(1, strlen(images[i]) * 2 + 2);
+		for (int j = 0; j < strlen(images[i]); j++)
+			images_u16[i][j] = (uint16_t)images[i][j];
+	}
+
+	if (debug) {
+		fprintf(stderr, "GUID:         ");
+		uuid_bin_to_str((uint8_t *)&namespace, uuid_str, UUID_STR_FORMAT_GUID);
+		fprintf(stderr, "%s\n", uuid_str);
+		fprintf(stderr, "Compatible:  \"%s\"\n", compatible);
+		fprintf(stderr, "Images:      ");
+		for (int i = 0; i < n_images; i++)
+			fprintf(stderr, "\"%s\"%s", argv[optind + i + 1],
+				i == n_images - 1 ? "\n" : ", ");
+	}
+
+	image_uuids = calloc(n_images, sizeof(char *));
+	for (int i = 0; i < n_images; i++) {
+		struct uuid image_type_id;
+
+		gen_uuid_v5(&namespace, &image_type_id,
+			    compatible, strlen(compatible),
+			    images_u16[i], u16_strsize(images_u16[i]) - sizeof(uint16_t),
+			    NULL);
+
+		uuid_bin_to_str((uint8_t *)&image_type_id, uuid_str, UUID_STR_FORMAT_GUID);
+		image_uuids[i] = strdup(uuid_str);
+	}
+
+	if (json) {
+		printf("[\n");
+		for (int i = 0; i < n_images; i++)
+			printf("\t{\"name\": \"%s\", \"uuid\": \"%s\"}%s\n", images[i], image_uuids[i],
+			       i == n_images - 1 ? "" : ",");
+		printf("]\n");
+	} else {
+		for (int i = 0; i < n_images; i++)
+			printf("%-24s| %s\n", images[i], image_uuids[i]);
+	}
+
+	return 0;
+}
+

-- 
2.45.0