mgmt/MCUmgr/grp/os: Add booloader info support

Adds command allowing to query information on bootloader.
In this case support is provided to query MCUboot information.

Signed-off-by: Dominik Ermel <dominik.ermel@nordicsemi.no>

include/zephyr/mgmt/mcumgr/grp/os_mgmt/os_mgmt.h

@@ -24,6 +24,7 @@ extern "C" {
 #define OS_MGMT_ID_RESET		5
 #define OS_MGMT_ID_MCUMGR_PARAMS	6
 #define OS_MGMT_ID_INFO			7
+#define OS_MGMT_ID_BOOTLOADER_INFO	8
 
 /**
  * Command result codes for OS management group.
@@ -37,6 +38,9 @@ enum os_mgmt_err_code_t {
 
 	/** The provided format value is not valid. */
 	OS_MGMT_ERR_INVALID_FORMAT,
+
+	/** Query was not recognized. */
+	OS_MGMT_ERR_QUERY_YIELDS_NO_ANSWER,
 };
 
 /* Bitmask values used by the os info command handler. Note that the width of this variable is

subsys/mgmt/mcumgr/grp/os_mgmt/CMakeLists.txt

@@ -1,6 +1,6 @@
 #
 # Copyright (c) 2018-2021 mcumgr authors
-# Copyright (c) 2022 Nordic Semiconductor ASA
+# Copyright (c) 2022-2023 Nordic Semiconductor ASA
 #
 # SPDX-License-Identifier: Apache-2.0
 #
@@ -12,6 +12,12 @@ zephyr_library_sources(src/os_mgmt.c)
 
 zephyr_library_include_directories(include)
 
+if (CONFIG_MCUMGR_GRP_OS_BOOTLOADER_INFO)
+    zephyr_include_directories(
+        ${ZEPHYR_MCUBOOT_MODULE_DIR}/boot/bootutil/include
+    )
+endif()
+
 if(DEFINED CONFIG_MCUMGR_GRP_OS_INFO_BUILD_DATE_TIME)
   set(MCUMGR_GRP_OS_INFO_BUILD_DATE_TIME_DIR ${PROJECT_BINARY_DIR}/os_mgmt_auto)
   file(MAKE_DIRECTORY ${MCUMGR_GRP_OS_INFO_BUILD_DATE_TIME_DIR})

subsys/mgmt/mcumgr/grp/os_mgmt/Kconfig

@@ -173,6 +173,16 @@ config MCUMGR_GRP_OS_INFO_BUILD_DATE_TIME
 
 endif
 
+if BOOTLOADER_MCUBOOT
+
+config MCUMGR_GRP_OS_BOOTLOADER_INFO
+	bool "Bootloader information"
+	help
+	  Allows to query MCUmgr about bootloader used by device and various bootloader
+	  parameters.
+
+endif # BOOTLOADER_MCUBOOT
+
 module = MCUMGR_GRP_OS
 module-str = mcumgr_grp_os
 source "subsys/logging/Kconfig.template.log_config"

subsys/mgmt/mcumgr/grp/os_mgmt/src/os_mgmt.c

@@ -33,10 +33,15 @@
 #include <zephyr/mgmt/mcumgr/mgmt/callbacks.h>
 #endif
 
-#ifdef CONFIG_MCUMGR_GRP_OS_INFO
+#if defined(CONFIG_MCUMGR_GRP_OS_INFO) || defined(CONFIG_MCUMGR_GRP_OS_BOOTLOADER_INFO)
 #include <stdio.h>
 #include <version.h>
+#if defined(CONFIG_MCUMGR_GRP_OS_INFO)
 #include <os_mgmt_processor.h>
+#endif
+#if defined(CONFIG_MCUMGR_GRP_OS_BOOTLOADER_INFO)
+#include <bootutil/boot_status.h>
+#endif
 #include <mgmt/mcumgr/util/zcbor_bulk.h>
 #if defined(CONFIG_NET_HOSTNAME_ENABLE)
 #include <zephyr/net/hostname.h>
@@ -370,6 +375,64 @@ os_mgmt_mcumgr_params(struct smp_streamer *ctxt)
 }
 #endif
 
+#if defined(CONFIG_MCUMGR_GRP_OS_BOOTLOADER_INFO)
+
+#if IS_ENABLED(CONFIG_MCUBOOT_BOOTLOADER_MODE_SINGLE_APP)
+#define BOOTLOADER_MODE MCUBOOT_MODE_SINGLE_SLOT
+#elif IS_ENABLED(CONFIG_MCUBOOT_BOOTLOADER_MODE_SWAP_SCRATCH)
+#define BOOTLOADER_MODE MCUBOOT_MODE_SWAP_USING_SCRATCH
+#elif IS_ENABLED(CONFIG_MCUBOOT_BOOTLOADER_MODE_OVERWRITE_ONLY)
+#define BOOTLOADER_MODE MCUBOOT_MODE_UPGRADE_ONLY
+#elif IS_ENABLED(CONFIG_MCUBOOT_BOOTLOADER_MODE_SWAP_WITHOUT_SCRATCH)
+#define BOOTLOADER_MODE MCUBOOT_MODE_SWAP_USING_MOVE
+#elif IS_ENABLED(CONFIG_MCUBOOT_BOOTLOADER_MODE_DIRECT_XIP)
+#define BOOTLOADER_MODE MCUBOOT_MODE_DIRECT_XIP
+#elif IS_ENABLED(CONFIG_MCUBOOT_BOOTLOADER_MODE_DIRECT_XIP_WITH_REVERT)
+#define BOOTLOADER_MODE MCUBOOT_MODE_DIRECT_XIP_WITH_REVERT
+#else
+#define BOOTLOADER_MODE -1
+#endif
+
+static int
+os_mgmt_bootloader_info(struct smp_streamer *ctxt)
+{
+	zcbor_state_t *zse = ctxt->writer->zs;
+	zcbor_state_t *zsd = ctxt->reader->zs;
+	struct zcbor_string query = { 0 };
+	size_t decoded;
+	bool ok;
+
+	struct zcbor_map_decode_key_val bootloader_info[] = {
+		ZCBOR_MAP_DECODE_KEY_DECODER("query", zcbor_tstr_decode, &query),
+	};
+
+	if (zcbor_map_decode_bulk(zsd, bootloader_info, ARRAY_SIZE(bootloader_info), &decoded)) {
+		return MGMT_ERR_EINVAL;
+	}
+
+	/* If no parameter is recognized then just introduce the bootloader. */
+	if (decoded == 0) {
+		ok = zcbor_tstr_put_lit(zse, "bootloader") &&
+		     zcbor_tstr_put_lit(zse, "MCUboot");
+	} else if (zcbor_map_decode_bulk_key_found(bootloader_info, ARRAY_SIZE(bootloader_info),
+		   "query") &&
+		   (sizeof("mode") - 1) == query.len &&
+		   memcmp("mode", query.value, query.len) == 0) {
+
+		ok = zcbor_tstr_put_lit(zse, "mode") &&
+		     zcbor_int32_put(zse, BOOTLOADER_MODE);
+#if IS_ENABLED(MCUBOOT_BOOTLOADER_NO_DOWNGRADE)
+		ok = zcbor_tstr_put_lit(zse, "no-downgrade") &&
+		     zcbor_bool_encode(zse, true);
+#endif
+	} else {
+		return OS_MGMT_ERR_QUERY_YIELDS_NO_ANSWER;
+	}
+
+	return ok ? MGMT_ERR_EOK : MGMT_ERR_EMSGSIZE;
+}
+#endif
+
 #ifdef CONFIG_MCUMGR_GRP_OS_INFO
 /**
  * Command handler: os info
@@ -733,6 +796,11 @@ static const struct mgmt_handler os_mgmt_group_handlers[] = {
 		os_mgmt_info, NULL
 	},
 #endif
+#ifdef CONFIG_MCUMGR_GRP_OS_BOOTLOADER_INFO
+	[OS_MGMT_ID_BOOTLOADER_INFO] = {
+		os_mgmt_bootloader_info, NULL
+	},
+#endif
 };
 
 #define OS_MGMT_GROUP_SZ ARRAY_SIZE(os_mgmt_group_handlers)