vbe: Add a new vbe command

Add a command to look at VBE methods and their status. Provide a test for
all of this as well.

Signed-off-by: Simon Glass <sjg@chromium.org>

cmd/Kconfig

@@ -330,6 +330,16 @@ config BOOTM_RTEMS
 	help
 	  Support booting RTEMS images via the bootm command.
 
+config CMD_VBE
+	bool "vbe - Verified Boot for Embedded"
+	depends on BOOTMETH_VBE
+	default y
+	help
+	  Provides various subcommands related to VBE, such as listing the
+	  available methods, looking at the state and changing which method
+	  is used to boot. Updating the parameters is not currently
+	  supported.
+
 config BOOTM_VXWORKS
 	bool "Support booting VxWorks OS images"
 	depends on CMD_BOOTM

cmd/Makefile

@@ -179,6 +179,7 @@ obj-$(CONFIG_CMD_FS_UUID) += fs_uuid.o
 obj-$(CONFIG_CMD_USB_MASS_STORAGE) += usb_mass_storage.o
 obj-$(CONFIG_CMD_USB_SDP) += usb_gadget_sdp.o
 obj-$(CONFIG_CMD_THOR_DOWNLOAD) += thordown.o
+obj-$(CONFIG_CMD_VBE) += vbe.o
 obj-$(CONFIG_CMD_XIMG) += ximg.o
 obj-$(CONFIG_CMD_YAFFS2) += yaffs2.o
 obj-$(CONFIG_CMD_SPL) += spl.o

cmd/vbe.c

@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Verified Boot for Embedded (VBE) command
+ *
+ * Copyright 2022 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#include <common.h>
+#include <bootmeth.h>
+#include <bootstd.h>
+#include <command.h>
+#include <vbe.h>
+
+static int do_vbe_list(struct cmd_tbl *cmdtp, int flag, int argc,
+		       char *const argv[])
+{
+	vbe_list();
+
+	return 0;
+}
+
+static int do_vbe_select(struct cmd_tbl *cmdtp, int flag, int argc,
+			 char *const argv[])
+{
+	struct bootstd_priv *std;
+	struct udevice *dev;
+	int ret;
+
+	ret = bootstd_get_priv(&std);
+	if (ret)
+		return CMD_RET_FAILURE;
+	if (argc < 2) {
+		std->vbe_bootmeth = NULL;
+		return 0;
+	}
+	if (vbe_find_by_any(argv[1], &dev))
+		return CMD_RET_FAILURE;
+
+	std->vbe_bootmeth = dev;
+
+	return 0;
+}
+
+static int do_vbe_info(struct cmd_tbl *cmdtp, int flag, int argc,
+		       char *const argv[])
+{
+	struct bootstd_priv *std;
+	char buf[256];
+	int ret, len;
+
+	ret = bootstd_get_priv(&std);
+	if (ret)
+		return CMD_RET_FAILURE;
+	if (!std->vbe_bootmeth) {
+		printf("No VBE bootmeth selected\n");
+		return CMD_RET_FAILURE;
+	}
+	ret = bootmeth_get_state_desc(std->vbe_bootmeth, buf, sizeof(buf));
+	if (ret) {
+		printf("Failed (err=%d)\n", ret);
+		return CMD_RET_FAILURE;
+	}
+	len = strnlen(buf, sizeof(buf));
+	if (len >= sizeof(buf)) {
+		printf("Buffer overflow\n");
+		return CMD_RET_FAILURE;
+	}
+
+	puts(buf);
+	if (buf[len] != '\n')
+		putc('\n');
+
+	return 0;
+}
+
+#ifdef CONFIG_SYS_LONGHELP
+static char vbe_help_text[] =
+	"list   - list VBE bootmeths\n"
+	"vbe select - select a VBE bootmeth by sequence or name\n"
+	"vbe info   - show information about a VBE bootmeth";
+#endif
+
+U_BOOT_CMD_WITH_SUBCMDS(vbe, "Verified Boot for Embedded", vbe_help_text,
+	U_BOOT_SUBCMD_MKENT(list, 1, 1, do_vbe_list),
+	U_BOOT_SUBCMD_MKENT(select, 2, 1, do_vbe_select),
+	U_BOOT_SUBCMD_MKENT(info, 2, 1, do_vbe_info));

test/boot/vbe_simple.c

@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Test for vbe-simple bootmeth. All start with 'vbe_simple'
+ *
+ * Copyright 2023 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#include <common.h>
+#include <bootmeth.h>
+#include <dm.h>
+#include <image.h>
+#include <memalign.h>
+#include <mmc.h>
+#include <of_live.h>
+#include <vbe.h>
+#include <version_string.h>
+#include <linux/log2.h>
+#include <test/suites.h>
+#include <test/ut.h>
+#include <u-boot/crc.h>
+#include "bootstd_common.h"
+
+#define NVDATA_START_BLK	((0x400 + 0x400) / MMC_MAX_BLOCK_LEN)
+#define VERSION_START_BLK	((0x400 + 0x800) / MMC_MAX_BLOCK_LEN)
+#define TEST_VERSION		"U-Boot v2022.04-local2"
+#define TEST_VERNUM		0x00010002
+
+/* Basic test of reading nvdata and updating a fwupd node in the device tree */
+static int vbe_simple_test_base(struct unit_test_state *uts)
+{
+	ALLOC_CACHE_ALIGN_BUFFER(u8, buf, MMC_MAX_BLOCK_LEN);
+	const char *version, *bl_version;
+	struct event_ft_fixup fixup;
+	struct udevice *dev, *mmc;
+	struct device_node *np;
+	struct blk_desc *desc;
+	char fdt_buf[0x400];
+	char info[100];
+	int node_ofs;
+	ofnode node;
+	u32 vernum;
+
+	/* Set up the version string */
+	ut_assertok(uclass_get_device(UCLASS_MMC, 1, &mmc));
+	desc = blk_get_by_device(mmc);
+	ut_assertnonnull(desc);
+
+	memset(buf, '\0', MMC_MAX_BLOCK_LEN);
+	strcpy(buf, TEST_VERSION);
+	if (blk_dwrite(desc, VERSION_START_BLK, 1, buf) != 1)
+		return log_msg_ret("write", -EIO);
+
+	/* Set up the nvdata */
+	memset(buf, '\0', MMC_MAX_BLOCK_LEN);
+	buf[1] = ilog2(0x40) << 4 | 1;
+	*(u32 *)(buf + 4) = TEST_VERNUM;
+	buf[0] = crc8(0, buf + 1, 0x3f);
+	if (blk_dwrite(desc, NVDATA_START_BLK, 1, buf) != 1)
+		return log_msg_ret("write", -EIO);
+
+	/* Read the version back */
+	ut_assertok(vbe_find_by_any("firmware0", &dev));
+	ut_assertok(bootmeth_get_state_desc(dev, info, sizeof(info)));
+	ut_asserteq_str("Version: " TEST_VERSION "\nVernum: 1/2", info);
+
+	ut_assertok(fdt_create_empty_tree(fdt_buf, sizeof(fdt_buf)));
+	node_ofs = fdt_add_subnode(fdt_buf, 0, "chosen");
+	ut_assert(node_ofs > 0);
+
+	node_ofs = fdt_add_subnode(fdt_buf, node_ofs, "fwupd");
+	ut_assert(node_ofs > 0);
+
+	node_ofs = fdt_add_subnode(fdt_buf, node_ofs, "firmware0");
+	ut_assert(node_ofs > 0);
+
+	/*
+	 * This can only work on the live tree, since the ofnode interface for
+	 * flat tree assumes that ofnode points to the control FDT
+	 */
+	ut_assertok(unflatten_device_tree(fdt_buf, &np));
+
+	/*
+	 * It would be better to call image_setup_libfdt() here, but that
+	 * function does not allow passing an ofnode. We can pass fdt_buf but
+	 * when it comes to send the evenr, it creates an ofnode that uses the
+	 * control FDT, since it has no way of accessing the live tree created
+	 * here.
+	 *
+	 * Two fix this we need:
+	 * - image_setup_libfdt() is updated to use ofnode
+	 * - ofnode updated to support access to an FDT other than the control
+	 *   FDT. This is partially implemented with live tree, but not with
+	 *   flat tree
+	 */
+	fixup.tree.np = np;
+	ut_assertok(event_notify(EVT_FT_FIXUP, &fixup, sizeof(fixup)));
+
+	node = ofnode_path_root(fixup.tree, "/chosen/fwupd/firmware0");
+
+	version = ofnode_read_string(node, "cur-version");
+	ut_assertnonnull(version);
+	ut_asserteq_str(TEST_VERSION, version);
+
+	ut_assertok(ofnode_read_u32(node, "cur-vernum", &vernum));
+	ut_asserteq(TEST_VERNUM, vernum);
+
+	bl_version = ofnode_read_string(node, "bootloader-version");
+	ut_assertnonnull(bl_version);
+	ut_asserteq_str(version_string, bl_version);
+
+	return 0;
+}
+BOOTSTD_TEST(vbe_simple_test_base, UT_TESTF_DM | UT_TESTF_SCAN_FDT |
+	     UT_TESTF_LIVE_TREE);