/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <fcntl.h>
#include <linux/loop.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/file.h>
#include <unistd.h>

#include "sd-device.h"

#include "architecture.h"
#include "argv-util.h"
#include "blockdev-util.h"
#include "build.h"
#include "capability-util.h"
#include "chase.h"
#include "copy.h"
#include "device-util.h"
#include "discover-image.h"
#include "dissect-image.h"
#include "env-util.h"
#include "errno-util.h"
#include "escape.h"
#include "extract-word.h"
#include "fd-util.h"
#include "fileio.h"
#include "format-table.h"
#include "format-util.h"
#include "fs-util.h"
#include "hashmap.h"
#include "hexdecoct.h"
#include "image-policy.h"
#include "json-util.h"
#include "libarchive-util.h"
#include "log.h"
#include "loop-util.h"
#include "main-func.h"
#include "mkdir.h"
#include "mount-util.h"
#include "mountpoint-util.h"
#include "namespace-util.h"
#include "nsresource.h"
#include "options.h"
#include "parse-argument.h"
#include "parse-util.h"
#include "path-util.h"
#include "pretty-print.h"
#include "process-util.h"
#include "recurse-dir.h"
#include "runtime-scope.h"
#include "sha256.h"
#include "shift-uid.h"
#include "stat-util.h"
#include "string-util.h"
#include "strv.h"
#include "tar-util.h"
#include "terminal-util.h"
#include "tmpfile-util.h"
#include "uid-classification.h"
#include "user-util.h"
#include "vpick.h"

static enum {
        ACTION_DISSECT,
        ACTION_MOUNT,
        ACTION_UMOUNT,
        ACTION_ATTACH,
        ACTION_DETACH,
        ACTION_LIST,
        ACTION_MTREE,
        ACTION_WITH,
        ACTION_COPY_FROM,
        ACTION_COPY_TO,
        ACTION_DISCOVER,
        ACTION_VALIDATE,
        ACTION_MAKE_ARCHIVE,
        ACTION_SHIFT,
} arg_action = ACTION_DISSECT;
static char *arg_image = NULL;
static char *arg_root = NULL;
static char *arg_path = NULL;
static const char *arg_source = NULL;
static const char *arg_target = NULL;
static DissectImageFlags arg_flags =
        DISSECT_IMAGE_GENERIC_ROOT |
        DISSECT_IMAGE_DISCARD_ON_LOOP |
        DISSECT_IMAGE_RELAX_VAR_CHECK |
        DISSECT_IMAGE_FSCK |
        DISSECT_IMAGE_USR_NO_ROOT |
        DISSECT_IMAGE_GROWFS |
        DISSECT_IMAGE_PIN_PARTITION_DEVICES |
        DISSECT_IMAGE_ADD_PARTITION_DEVICES |
        DISSECT_IMAGE_ALLOW_USERSPACE_VERITY;
static VeritySettings arg_verity_settings = VERITY_SETTINGS_DEFAULT;
static sd_json_format_flags_t arg_json_format_flags = SD_JSON_FORMAT_OFF;
static PagerFlags arg_pager_flags = 0;
static bool arg_legend = true;
static bool arg_rmdir = false;
static bool arg_in_memory = false;
static char **arg_argv = NULL;
static char *arg_loop_ref = NULL;
static bool arg_loop_ref_auto = false;
static ImagePolicy *arg_image_policy = NULL;
static bool arg_mtree_hash = true;
static bool arg_via_service = false;
static RuntimeScope arg_runtime_scope = _RUNTIME_SCOPE_INVALID;
static bool arg_all = false;
static uid_t arg_uid_base = UID_INVALID;
static bool arg_quiet = false;
static ImageFilter *arg_image_filter = NULL;
static int arg_copy_ownership = -1;

STATIC_DESTRUCTOR_REGISTER(arg_image, freep);
STATIC_DESTRUCTOR_REGISTER(arg_root, freep);
STATIC_DESTRUCTOR_REGISTER(arg_path, freep);
STATIC_DESTRUCTOR_REGISTER(arg_verity_settings, verity_settings_done);
STATIC_DESTRUCTOR_REGISTER(arg_argv, strv_freep);
STATIC_DESTRUCTOR_REGISTER(arg_loop_ref, freep);
STATIC_DESTRUCTOR_REGISTER(arg_image_policy, image_policy_freep);
STATIC_DESTRUCTOR_REGISTER(arg_image_filter, image_filter_freep);

static int help(void) {
        _cleanup_free_ char *link = NULL;
        _cleanup_(table_unrefp) Table *options = NULL, *commands = NULL;
        int r;

        pager_open(arg_pager_flags);

        r = terminal_urlify_man("systemd-dissect", "1", &link);
        if (r < 0)
                return log_oom();

        r = option_parser_get_help_table_ns("systemd-dissect", &options);
        if (r < 0)
                return r;

        r = option_parser_get_help_table_full("systemd-dissect", "Commands", &commands);
        if (r < 0)
                return r;

        /* Make the 1st column same width in both tables */
        (void) table_sync_column_widths(0, options, commands);

        printf("%1$s [OPTIONS...] IMAGE\n"
               "%1$s [OPTIONS...] --mount IMAGE PATH\n"
               "%1$s [OPTIONS...] --umount PATH\n"
               "%1$s [OPTIONS...] --attach IMAGE\n"
               "%1$s [OPTIONS...] --detach PATH\n"
               "%1$s [OPTIONS...] --list IMAGE\n"
               "%1$s [OPTIONS...] --mtree IMAGE\n"
               "%1$s [OPTIONS...] --with IMAGE [COMMAND…]\n"
               "%1$s [OPTIONS...] --copy-from IMAGE PATH [TARGET]\n"
               "%1$s [OPTIONS...] --copy-to IMAGE [SOURCE] PATH\n"
               "%1$s [OPTIONS...] --make-archive IMAGE [TARGET]\n"
               "%1$s [OPTIONS...] --discover\n"
               "%1$s [OPTIONS...] --validate IMAGE\n"
               "%1$s [OPTIONS...] --shift IMAGE UIDBASE\n"
               "\n%2$sDissect a Discoverable Disk Image (DDI).%3$s\n"
               "\n%4$sOptions:%5$s\n",
               program_invocation_short_name,
               ansi_highlight(),
               ansi_normal(),
               ansi_underline(),
               ansi_normal());

        r = table_print_or_warn(options);
        if (r < 0)
                return r;

        printf("\n%sCommands:%s\n", ansi_underline(), ansi_normal());

        r = table_print_or_warn(commands);
        if (r < 0)
                return r;

        printf("\nSee the %s for details.\n", link);
        return 0;
}

static int parse_image_path_argument(const char *path, char **ret_root, char **ret_image) {
        _cleanup_free_ char *p = NULL;
        struct stat st;
        int r;

        assert(ret_image);

        r = parse_path_argument(path, /* suppress_root= */ false, &p);
        if (r < 0)
                return r;

        /* If we got a sysfs path (e.g. from a udev-instantiated template unit's %f specifier),
         * resolve it to the corresponding devnode. */
        if (path_startswith(p, "/sys/")) {
                _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
                const char *devname;

                r = sd_device_new_from_syspath(&dev, p);
                if (r < 0)
                        return log_error_errno(r, "Failed to get device from syspath '%s': %m", p);

                r = sd_device_get_devname(dev, &devname);
                if (r < 0)
                        return log_error_errno(r, "Failed to get devname for '%s': %m", p);

                r = free_and_strdup(&p, devname);
                if (r < 0)
                        return log_oom();
        }

        if (stat(p, &st) < 0)
                return log_error_errno(errno, "Failed to stat %s: %m", p);

        if (S_ISDIR(st.st_mode)) {
                if (!ret_root)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "%s is not an image file.", p);

                *ret_root = TAKE_PTR(p);
        } else
                *ret_image = TAKE_PTR(p);

        return 0;
}

static int parse_argv(int argc, char *argv[]) {
        bool system_scope_requested = false, user_scope_requested = false;
        int r;

        assert(argc >= 0);
        assert(argv);

        OptionParser opts = { argc, argv, .namespace = "systemd-dissect" };

        FOREACH_OPTION_OR_RETURN(c, &opts)
                switch (c) {

                OPTION_NAMESPACE("systemd-dissect"): {}

                OPTION_COMMON_NO_PAGER:
                        arg_pager_flags |= PAGER_DISABLE;
                        break;

                OPTION_COMMON_NO_LEGEND:
                        arg_legend = false;
                        break;

                OPTION_LONG("mkdir", NULL, "Make mount directory before mounting, if missing"):
                        arg_flags |= DISSECT_IMAGE_MKDIR;
                        break;

                OPTION_LONG("rmdir", NULL, "Remove mount directory after unmounting"):
                        arg_rmdir = true;
                        break;

                OPTION('r', "read-only", NULL, "Mount read-only"):
                        arg_flags |= DISSECT_IMAGE_READ_ONLY;
                        break;

                OPTION_LONG("discard", "MODE", "Choose discard mode (disabled, loop, all, crypto)"): {
                        DissectImageFlags flags;

                        if (streq(opts.arg, "disabled"))
                                flags = 0;
                        else if (streq(opts.arg, "loop"))
                                flags = DISSECT_IMAGE_DISCARD_ON_LOOP;
                        else if (streq(opts.arg, "all"))
                                flags = DISSECT_IMAGE_DISCARD_ON_LOOP | DISSECT_IMAGE_DISCARD;
                        else if (streq(opts.arg, "crypt"))
                                flags = DISSECT_IMAGE_DISCARD_ANY;
                        else if (streq(opts.arg, "list")) {
                                puts("disabled\n"
                                     "all\n"
                                     "crypt\n"
                                     "loop");
                                return 0;
                        } else
                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                                       "Unknown --discard= parameter: %s", opts.arg);
                        arg_flags = (arg_flags & ~DISSECT_IMAGE_DISCARD_ANY) | flags;

                        break;
                }

                OPTION_LONG("in-memory", NULL, "Copy image into memory"):
                        arg_in_memory = true;
                        break;

                OPTION_LONG("root-hash", "HASH", "Specify root hash for verity"): {}
                OPTION_LONG("usr-hash", "HASH", "Same, but for the usr partition"): {
                        _cleanup_(iovec_done) struct iovec roothash = {};

                        PartitionDesignator d = streq(opts.opt->long_code, "root-hash") ? PARTITION_ROOT : PARTITION_USR;
                        if (arg_verity_settings.designator >= 0 &&
                            arg_verity_settings.designator != d)
                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                                       "Cannot combine --root-hash=/--root-hash-sig= and --usr-hash=/--usr-hash-sig= options.");

                        r = unhexmem(opts.arg, &roothash.iov_base, &roothash.iov_len);
                        if (r < 0)
                                return log_error_errno(r, "Failed to parse root hash '%s': %m", opts.arg);
                        if (roothash.iov_len < sizeof(sd_id128_t))
                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                                       "Root hash must be at least 128-bit long: %s", opts.arg);

                        iovec_done(&arg_verity_settings.root_hash);
                        arg_verity_settings.root_hash = TAKE_STRUCT(roothash);
                        arg_verity_settings.designator = d;
                        break;
                }

                OPTION_LONG("root-hash-sig", "SIG",
                            "Specify signature of root hash for verity as DER-encoded PKCS7, "
                            "either as a path to a file or as an ASCII base64-encoded string "
                            "prefixed by 'base64:'"): {}
                OPTION_LONG("usr-hash-sig", "SIG", "Same, but for the usr partition"): {
                        const char *value;
                        _cleanup_(iovec_done) struct iovec sig = {};

                        PartitionDesignator d = streq(opts.opt->long_code, "root-hash-sig") ? PARTITION_ROOT : PARTITION_USR;
                        if (arg_verity_settings.designator >= 0 &&
                            arg_verity_settings.designator != d)
                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                                       "Cannot combine --root-hash=/--root-hash-sig= and --usr-hash=/--usr-hash-sig= options.");

                        if ((value = startswith(opts.arg, "base64:"))) {
                                r = unbase64mem(value, &sig.iov_base, &sig.iov_len);
                                if (r < 0)
                                        return log_error_errno(r, "Failed to parse root hash signature '%s': %m", opts.arg);
                        } else {
                                r = read_full_file(opts.arg, (char**) &sig.iov_base, &sig.iov_len);
                                if (r < 0)
                                        return log_error_errno(r, "Failed to read root hash signature file '%s': %m", opts.arg);
                        }

                        iovec_done(&arg_verity_settings.root_hash_sig);
                        arg_verity_settings.root_hash_sig = TAKE_STRUCT(sig);
                        arg_verity_settings.designator = d;
                        break;
                }

                OPTION_LONG("verity-data", "PATH",
                            "Specify data file with hash tree for verity if it is not embedded in IMAGE"):
                        r = parse_path_argument(opts.arg, false, &arg_verity_settings.data_path);
                        if (r < 0)
                                return r;
                        break;

                OPTION_LONG("fsck", "BOOL", "Run fsck before mounting"):
                        r = parse_boolean(opts.arg);
                        if (r < 0)
                                return log_error_errno(r, "Failed to parse --fsck= parameter: %s", opts.arg);

                        SET_FLAG(arg_flags, DISSECT_IMAGE_FSCK, r);
                        break;

                OPTION_LONG("growfs", "BOOL", "Grow file system to partition size, if marked"):
                        r = parse_boolean(opts.arg);
                        if (r < 0)
                                return log_error_errno(r, "Failed to parse --growfs= parameter: %s", opts.arg);

                        SET_FLAG(arg_flags, DISSECT_IMAGE_GROWFS, r);
                        break;

                OPTION_COMMON_JSON:
                        r = parse_json_argument(opts.arg, &arg_json_format_flags);
                        if (r <= 0)
                                return r;
                        break;

                OPTION_LONG("loop-ref", "NAME", "Set reference string for loopback device"):
                        if (isempty(opts.arg)) {
                                arg_loop_ref = mfree(arg_loop_ref);
                                arg_loop_ref_auto = false;
                                break;
                        }

                        if (strlen(opts.arg) >= sizeof_field(struct loop_info64, lo_file_name))
                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Loop device ref string '%s' is too long.", opts.arg);

                        r = free_and_strdup_warn(&arg_loop_ref, opts.arg);
                        if (r < 0)
                                return r;

                        arg_loop_ref_auto = false;
                        break;

                OPTION_LONG("loop-ref-auto", NULL, "Derive reference string from image file name"):
                        arg_loop_ref = mfree(arg_loop_ref);
                        arg_loop_ref_auto = true;
                        break;

                OPTION_LONG("image-policy", "POLICY", "Specify image dissection policy"):
                        r = parse_image_policy_argument(opts.arg, &arg_image_policy);
                        if (r < 0)
                                return r;
                        break;

                OPTION_LONG("mtree-hash", "BOOL", "Whether to include SHA256 hash in the mtree output"):
                        r = parse_boolean_argument("--mtree-hash=", opts.arg, &arg_mtree_hash);
                        if (r < 0)
                                return r;
                        break;

                OPTION_LONG("system", NULL, "Discover system images"):
                        system_scope_requested = true;
                        break;

                OPTION_LONG("user", NULL, "Discover user images"):
                        user_scope_requested = true;
                        break;

                OPTION_LONG("all", NULL, "Show hidden images too"):
                        arg_all = true;
                        break;

                OPTION('q', "quiet", NULL, "Suppress output of chosen loopback block device"):
                        arg_quiet = true;
                        break;

                OPTION_LONG("image-filter", "FILTER", "Specify image dissection filter"): {
                        _cleanup_(image_filter_freep) ImageFilter *f = NULL;
                        r = image_filter_parse(opts.arg, &f);
                        if (r < 0)
                                return log_error_errno(r, "Failed to parse image filter expression: %s", opts.arg);

                        image_filter_free(arg_image_filter);
                        arg_image_filter = TAKE_PTR(f);
                        break;
                }

                OPTION_LONG("copy-ownership", "BOOL", "Whether to copy ownership when copying files"):
                        r = parse_tristate_argument_with_auto("--copy-ownership=", opts.arg, &arg_copy_ownership);
                        if (r < 0)
                                return r;
                        break;

                /************************************ Commands ***************************************/
                OPTION_GROUP("Commands"): {}

                OPTION_COMMON_HELP:
                        return help();

                OPTION_COMMON_VERSION:
                        return version();

                OPTION('m', "mount", NULL, "Mount the image to the specified directory"):
                        arg_action = ACTION_MOUNT;
                        break;

                OPTION_SHORT('M', NULL, "Shortcut for --mount --mkdir"):
                        arg_action = ACTION_MOUNT;
                        arg_flags |= DISSECT_IMAGE_MKDIR;
                        break;

                OPTION('u', "umount", NULL, "Unmount the image from the specified directory"):
                        arg_action = ACTION_UMOUNT;
                        break;

                OPTION_SHORT('U', NULL, "Shortcut for --umount --rmdir"):
                        arg_action = ACTION_UMOUNT;
                        arg_rmdir = true;
                        break;

                OPTION_LONG("attach", NULL, "Attach the disk image to a loopback block device"):
                        arg_action = ACTION_ATTACH;
                        break;

                OPTION_LONG("detach", NULL, "Detach a loopback block device again"):
                        arg_action = ACTION_DETACH;
                        break;

                OPTION('l', "list", NULL, "List all the files and directories of the specified OS image"):
                        arg_action = ACTION_LIST;
                        arg_flags |= DISSECT_IMAGE_READ_ONLY;
                        break;

                OPTION_LONG("mtree", NULL, "Show BSD mtree manifest of OS image"):
                        arg_action = ACTION_MTREE;
                        arg_flags |= DISSECT_IMAGE_READ_ONLY;
                        break;

                OPTION_FULL(OPTION_STOPS_PARSING, /* sc= */ 0, "with", NULL, "Mount, run command, unmount"):
                        arg_action = ACTION_WITH;
                        break;

                OPTION('x', "copy-from", NULL, "Copy files from image to host"):
                        arg_action = ACTION_COPY_FROM;
                        arg_flags |= DISSECT_IMAGE_READ_ONLY;
                        break;

                OPTION('a', "copy-to", NULL, "Copy files from host to image"):
                        arg_action = ACTION_COPY_TO;
                        break;

                OPTION_LONG("make-archive", NULL, "Convert the DDI to an archive file"):
                        r = DLOPEN_LIBARCHIVE(LOG_ERR, SD_ELF_NOTE_DLOPEN_PRIORITY_RECOMMENDED);
                        if (r < 0)
                                return r;

                        arg_action = ACTION_MAKE_ARCHIVE;
                        break;

                OPTION_LONG("discover", NULL, "Discover DDIs in well known directories"):
                        arg_action = ACTION_DISCOVER;
                        break;

                OPTION_LONG("validate", NULL, "Validate image and image policy"):
                        arg_action = ACTION_VALIDATE;
                        break;

                OPTION_LONG("shift", NULL, "Shift UID range to selected base"):
                        arg_action = ACTION_SHIFT;
                        break;
                }

        if (system_scope_requested || user_scope_requested)
                arg_runtime_scope = system_scope_requested && user_scope_requested ? _RUNTIME_SCOPE_INVALID :
                        system_scope_requested ? RUNTIME_SCOPE_SYSTEM : RUNTIME_SCOPE_USER;

        char **args = option_parser_get_args(&opts);

        switch (arg_action) {

        case ACTION_DISSECT:
                if (strv_length(args) != 1)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file path as only argument.");

                r = parse_image_path_argument(args[0], NULL, &arg_image);
                if (r < 0)
                        return r;

                /* when dumping image info be even more liberal than otherwise, do not even require a single valid partition */
                arg_flags |= DISSECT_IMAGE_READ_ONLY|DISSECT_IMAGE_ALLOW_EMPTY;
                break;

        case ACTION_MOUNT:
                if (strv_length(args) != 2)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file path and mount point path as only arguments.");

                r = parse_image_path_argument(args[0], NULL, &arg_image);
                if (r < 0)
                        return r;

                r = parse_path_argument(args[1], /* suppress_root= */ false, &arg_path);
                if (r < 0)
                        return r;

                arg_flags |= DISSECT_IMAGE_REQUIRE_ROOT;
                break;

        case ACTION_UMOUNT:
                if (strv_length(args) != 1)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected a mount point path as only argument.");

                r = parse_path_argument(args[0], /* suppress_root= */ false, &arg_path);
                if (r < 0)
                        return r;
                break;

        case ACTION_ATTACH:
                if (strv_length(args) != 1)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file path as only argument.");

                r = parse_image_path_argument(args[0], NULL, &arg_image);
                if (r < 0)
                        return r;
                break;

        case ACTION_DETACH:
                if (strv_length(args) != 1)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file path or loopback device as only argument.");

                r = parse_image_path_argument(args[0], NULL, &arg_image);
                if (r < 0)
                        return r;
                break;

        case ACTION_LIST:
        case ACTION_MTREE:
                if (strv_length(args) != 1)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file or directory path as only argument.");

                r = parse_image_path_argument(args[0], &arg_root, &arg_image);
                if (r < 0)
                        return r;

                arg_flags |= DISSECT_IMAGE_READ_ONLY | DISSECT_IMAGE_REQUIRE_ROOT;
                break;

        case ACTION_MAKE_ARCHIVE:
                if (!IN_SET(strv_length(args), 1, 2))
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file, and an optional target path as only arguments.");

                r = parse_image_path_argument(args[0], &arg_root, &arg_image);
                if (r < 0)
                        return r;

                arg_target = empty_or_dash_to_null(args[1]);
                arg_flags |= DISSECT_IMAGE_READ_ONLY | DISSECT_IMAGE_REQUIRE_ROOT;
                break;

        case ACTION_COPY_FROM:
                if (!IN_SET(strv_length(args), 2, 3))
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file or directory path, a source path and an optional destination path as only arguments.");

                r = parse_image_path_argument(args[0], &arg_root, &arg_image);
                if (r < 0)
                        return r;
                arg_source = args[1];
                arg_target = args[2] ?: "-"; /* this means stdout */ ;

                arg_flags |= DISSECT_IMAGE_READ_ONLY | DISSECT_IMAGE_REQUIRE_ROOT;
                break;

        case ACTION_COPY_TO:
                if (!IN_SET(strv_length(args), 2, 3))
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file or directory path, an optional source path and a destination path as only arguments.");

                r = parse_image_path_argument(args[0], &arg_root, &arg_image);
                if (r < 0)
                        return r;

                if (args[2]) {
                        arg_source = args[1];
                        arg_target = args[2];
                } else {
                        arg_source = "-"; /* this means stdin */
                        arg_target = args[1];
                }

                arg_flags |= DISSECT_IMAGE_REQUIRE_ROOT;
                break;

        case ACTION_WITH:
                if (strv_isempty(args))
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file path and an optional command line.");

                r = parse_image_path_argument(args[0], NULL, &arg_image);
                if (r < 0)
                        return r;

                if (args[1]) {
                        arg_argv = strv_copy(args + 1);
                        if (!arg_argv)
                                return log_oom();
                }

                break;

        case ACTION_DISCOVER:
                if (!strv_isempty(args))
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected no argument.");
                break;

        case ACTION_VALIDATE:
                if (strv_length(args) != 1)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image file path as only argument.");

                r = parse_image_path_argument(args[0], NULL, &arg_image);
                if (r < 0)
                        return r;

                arg_flags |= DISSECT_IMAGE_READ_ONLY;
                arg_flags &= ~(DISSECT_IMAGE_PIN_PARTITION_DEVICES|DISSECT_IMAGE_ADD_PARTITION_DEVICES);
                break;

        case ACTION_SHIFT:
                if (strv_length(args) != 2)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected an image path and a UID base as only argument.");

                r = parse_image_path_argument(args[0], &arg_root, &arg_image);
                if (r < 0)
                        return r;

                if (streq(args[1], "foreign"))
                        arg_uid_base = FOREIGN_UID_BASE;
                else {
                        r = parse_uid(args[1], &arg_uid_base);
                        if (r < 0)
                                return log_error_errno(r, "Failed to parse UID base: %s", args[1]);

                        if ((arg_uid_base & 0xFFFF) != 0)
                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                                       "Selected UID base not a multiple of 64K: " UID_FMT, arg_uid_base);
                        if (arg_uid_base != 0 &&
                            !uid_is_container(arg_uid_base) &&
                            !uid_is_foreign(arg_uid_base))
                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                                       "Selected UID range is not in the container range, nor the foreign one, refusing.");
                }

                arg_flags |= DISSECT_IMAGE_REQUIRE_ROOT;
                break;

        default:
                assert_not_reached();
        }

        r = getenv_bool("SYSTEMD_USE_MOUNTFSD");
        if (r < 0) {
                if (r != -ENXIO)
                        return log_error_errno(r, "Failed to parse $SYSTEMD_USE_MOUNTFSD: %m");
        } else
                arg_via_service = r;

        if (IN_SET(arg_action, ACTION_MOUNT, ACTION_UMOUNT)) {
                r = have_effective_cap(CAP_SYS_ADMIN);
                if (r < 0)
                        return log_error_errno(r, "Failed to determine if we have CAP_SYS_ADMIN: %m");
                if (r == 0)
                        return log_error_errno(SYNTHETIC_ERRNO(EPERM), "Need to have CAP_SYS_ADMIN to mount/unmount images");
        }

        if (arg_action == ACTION_SHIFT) {
                r = have_effective_cap(CAP_CHOWN);
                if (r < 0)
                        return log_error_errno(r, "Failed to determine if we have CAP_CHOWN: %m");
                if (r == 0)
                        return log_error_errno(SYNTHETIC_ERRNO(EPERM), "Need to have CAP_CHOWN to shift UID ranges");
        }

        if (IN_SET(arg_action, ACTION_ATTACH, ACTION_DETACH)) {
                r = must_be_root();
                if (r < 0)
                        return r;
        }

        SET_FLAG(arg_flags, DISSECT_IMAGE_ALLOW_INTERACTIVE_AUTH, isatty_safe(STDIN_FILENO));

        return 1;
}

static int parse_argv_as_mount_helper(int argc, char *argv[]) {
        const char *options = NULL;
        bool fake = false;
        int r;

        /* Implements util-linux "external helper" command line interface, as per mount(8) man page. */

        OptionParser opts = { argc, argv, .namespace = "mount.ddi" };
        FOREACH_OPTION_OR_RETURN(c, &opts)
                switch (c) {

                OPTION_NAMESPACE("mount.ddi"): {}

                OPTION_SHORT('f', NULL, /* help= */ NULL):
                        fake = true;
                        break;

                OPTION_SHORT('o', "OPTIONS", /* help= */ NULL):
                        options = opts.arg;
                        break;

                OPTION_SHORT('t', "FSTYPE", /* help= */ NULL):
                        if (!streq(opts.arg, "ddi"))
                                log_debug("Unexpected file system type '%s', ignoring.", opts.arg);
                        break;

                OPTION_SHORT('s', NULL, /* help= */ NULL): {} /* sloppy mount options */
                OPTION_SHORT('n', NULL, /* help= */ NULL): {} /* aka --no-mtab */
                OPTION_SHORT('v', NULL, /* help= */ NULL):    /* aka --verbose */
                        log_debug("Ignoring option -%c, not implemented.", opts.opt->short_code);
                        break;

                OPTION_SHORT('N', "NS", /* help= */ NULL): /* aka --namespace= */
                        return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
                                               "Option -%c is not implemented, refusing.",
                                               opts.opt->short_code);
                }

        char **args = option_parser_get_args(&opts);
        size_t n_args = option_parser_get_n_args(&opts);

        if (n_args != 2)
                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                       "Expected an image file path and target directory as only argument.");

        for (const char *p = options;;) {
                _cleanup_free_ char *word = NULL;

                r = extract_first_word(&p, &word, ",", EXTRACT_KEEP_QUOTE);
                if (r < 0)
                        return log_error_errno(r, "Failed to extract mount option: %m");
                if (r == 0)
                        break;

                if (streq(word, "ro"))
                        SET_FLAG(arg_flags, DISSECT_IMAGE_READ_ONLY, true);
                else if (streq(word, "rw"))
                        SET_FLAG(arg_flags, DISSECT_IMAGE_READ_ONLY, false);
                else if (streq(word, "discard"))
                        SET_FLAG(arg_flags, DISSECT_IMAGE_DISCARD_ANY, true);
                else if (streq(word, "nodiscard"))
                        SET_FLAG(arg_flags, DISSECT_IMAGE_DISCARD_ANY, false);
                else
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Unknown mount option '%s'.", word);
        }

        if (fake)
                return 0;

        r = parse_path_argument(args[0], /* suppress_root= */ false, &arg_image);
        if (r < 0)
                return r;

        r = parse_path_argument(args[1], /* suppress_root= */ false, &arg_path);
        if (r < 0)
                return r;

        arg_flags |= DISSECT_IMAGE_REQUIRE_ROOT;
        arg_action = ACTION_MOUNT;
        return 1;
}

static void strv_pair_print(char **l, const char *prefix) {
        assert(prefix);

        STRV_FOREACH_PAIR(p, q, l)
                if (p == l)
                        printf("%s %s=%s\n", prefix, *p, *q);
                else
                        printf("%*s %s=%s\n", (int) strlen(prefix), "", *p, *q);
}

static int get_extension_scopes(DissectedImage *m, ImageClass class, char ***ret_scopes) {
        _cleanup_strv_free_ char **l = NULL;
        const char *e, *field_name;
        char **release_data;

        assert(m);
        assert(ret_scopes);

        switch (class) {

        case IMAGE_SYSEXT:
                release_data = m->sysext_release;
                field_name = "SYSEXT_SCOPE";
                break;

        case IMAGE_CONFEXT:
                release_data = m->confext_release;
                field_name = "CONFEXT_SCOPE";
                break;

        default:
                return -EINVAL;
        }

        /* If there's no extension-release file its not a system extension. Otherwise the SYSEXT_SCOPE
         * field for sysext images and the CONFEXT_SCOPE field for confext images indicates which scope
         * it is for — and it defaults to "system" + "portable" if unset. */

        if (!release_data) {
                *ret_scopes = NULL;
                return 0;
        }

        e = strv_env_pairs_get(release_data, field_name);
        if (e)
                l = strv_split(e, WHITESPACE);
        else
                l = strv_new("system", "portable");
        if (!l)
                return -ENOMEM;

        *ret_scopes = TAKE_PTR(l);
        return 1;
}

static int action_dissect(
                DissectedImage *m,
                LoopDevice *d,
                int userns_fd) {

        _cleanup_(sd_json_variant_unrefp) sd_json_variant *v = NULL;
        _cleanup_(table_unrefp) Table *t = NULL;
        _cleanup_free_ char *bn = NULL;
        uint64_t size = UINT64_MAX;
        int r;

        assert(m);

        r = path_extract_filename(arg_image, &bn);
        if (r < 0)
                return log_error_errno(r, "Failed to extract file name from image path '%s': %m", arg_image);

        if (arg_json_format_flags & (SD_JSON_FORMAT_OFF|SD_JSON_FORMAT_PRETTY|SD_JSON_FORMAT_PRETTY_AUTO))
                pager_open(arg_pager_flags);

        if (!sd_json_format_enabled(arg_json_format_flags)) {
                printf(" File Name: %s%s%s\n",
                       ansi_highlight(), bn, ansi_normal());

                printf("      Size: %s\n",
                       FORMAT_BYTES(m->image_size));

                printf(" Sec. Size: %" PRIu32 "\n",
                       m->sector_size);

                printf("     Arch.: %s\n",
                       strna(architecture_to_string(dissected_image_architecture(m))));

                if (!sd_id128_is_null(m->image_uuid))
                        printf("Image UUID: %s\n",
                               SD_ID128_TO_UUID_STRING(m->image_uuid));

                if (m->image_name && !streq(m->image_name, bn))
                        printf("Image Name: %s\n", m->image_name);

                putc('\n', stdout);
                fflush(stdout);
        }

        r = dissected_image_acquire_metadata(m, userns_fd, /* extra_flags= */ 0);
        if (r == -ENXIO)
                return log_error_errno(r, "No root partition discovered.");
        if (r == -EUCLEAN)
                return log_error_errno(r, "File system check of image failed.");
        if (r == -EMEDIUMTYPE)
                log_warning_errno(r, "Not a valid OS image, no os-release file included. Proceeding anyway.");
        else if (r == -EUNATCH)
                log_warning_errno(r, "OS image is encrypted, proceeding without showing OS image metadata.");
        else if (r == -EBUSY)
                log_warning_errno(r, "OS image is currently in use, proceeding without showing OS image metadata.");
        else if (r < 0)
                return log_error_errno(r, "Failed to acquire image metadata: %m");
        else if (!sd_json_format_enabled(arg_json_format_flags)) {

                if (m->hostname)
                        printf("  Hostname: %s\n", m->hostname);

                if (!sd_id128_is_null(m->machine_id))
                        printf("Machine ID: " SD_ID128_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(m->machine_id));

                strv_pair_print(m->machine_info,
                               "Mach. Info:");
                strv_pair_print(m->os_release,
                               "OS Release:");
                strv_pair_print(m->initrd_release,
                                "initrd R.:");
                strv_pair_print(m->sysext_release,
                               " sysext R.:");
                strv_pair_print(m->confext_release,
                               "confext R.:");

                if (m->hostname ||
                    !sd_id128_is_null(m->machine_id) ||
                    !strv_isempty(m->machine_info) ||
                    !strv_isempty(m->os_release) ||
                    !strv_isempty(m->initrd_release) ||
                    !strv_isempty(m->sysext_release) ||
                    !strv_isempty(m->confext_release))
                        putc('\n', stdout);

                printf("    Use As: %s bootable system for UEFI\n",
                       COLOR_MARK_BOOL(dissected_image_is_bootable_uefi(m)));
                printf("            %s bootable system for container\n",
                       COLOR_MARK_BOOL(dissected_image_is_bootable_os(m)));
                printf("            %s portable service\n",
                       COLOR_MARK_BOOL(dissected_image_is_portable(m)));
                printf("            %s initrd\n",
                       COLOR_MARK_BOOL(dissected_image_is_initrd(m)));

                for (ImageClass c = _IMAGE_CLASS_EXTENSION_FIRST; c <= _IMAGE_CLASS_EXTENSION_LAST; c++) {
                        const char *string_class = image_class_to_string(c);
                        _cleanup_strv_free_ char **extension_scopes = NULL;

                        r = get_extension_scopes(m, c, &extension_scopes);
                        if (r < 0)
                                return log_error_errno(r, "Failed to parse scopes: %m");

                        printf("            %s %s for system\n",
                               COLOR_MARK_BOOL(strv_contains(extension_scopes, "system")), string_class);
                        printf("            %s %s for portable service\n",
                               COLOR_MARK_BOOL(strv_contains(extension_scopes, "portable")), string_class);
                        printf("            %s %s for initrd\n",
                               COLOR_MARK_BOOL(strv_contains(extension_scopes, "initrd")), string_class);
                }

                putc('\n', stdout);
        } else {
                _cleanup_strv_free_ char **sysext_scopes = NULL, **confext_scopes = NULL;

                r = get_extension_scopes(m, IMAGE_SYSEXT, &sysext_scopes);
                if (r < 0)
                        return log_error_errno(r, "Failed to parse sysext scopes: %m");

                r = get_extension_scopes(m, IMAGE_CONFEXT, &confext_scopes);
                if (r < 0)
                        return log_error_errno(r, "Failed to parse confext scopes: %m");

                Architecture a = dissected_image_architecture(m);

                r = sd_json_buildo(
                                &v,
                                SD_JSON_BUILD_PAIR_STRING("name", bn),
                                SD_JSON_BUILD_PAIR_CONDITION(size != UINT64_MAX, "size", SD_JSON_BUILD_INTEGER(size)),
                                SD_JSON_BUILD_PAIR_INTEGER("sectorSize", m->sector_size),
                                SD_JSON_BUILD_PAIR_CONDITION(a >= 0, "architecture", SD_JSON_BUILD_STRING(architecture_to_string(a))),
                                SD_JSON_BUILD_PAIR_CONDITION(!sd_id128_is_null(m->image_uuid), "imageUuid", SD_JSON_BUILD_UUID(m->image_uuid)),
                                SD_JSON_BUILD_PAIR_CONDITION(!!m->hostname, "hostname", SD_JSON_BUILD_STRING(m->hostname)),
                                SD_JSON_BUILD_PAIR_CONDITION(!sd_id128_is_null(m->machine_id), "machineId", SD_JSON_BUILD_ID128(m->machine_id)),
                                SD_JSON_BUILD_PAIR_CONDITION(!strv_isempty(m->machine_info), "machineInfo", JSON_BUILD_STRV_ENV_PAIR(m->machine_info)),
                                SD_JSON_BUILD_PAIR_CONDITION(!strv_isempty(m->os_release), "osRelease", JSON_BUILD_STRV_ENV_PAIR(m->os_release)),
                                SD_JSON_BUILD_PAIR_CONDITION(!strv_isempty(m->initrd_release), "initrdRelease", JSON_BUILD_STRV_ENV_PAIR(m->initrd_release)),
                                SD_JSON_BUILD_PAIR_CONDITION(!strv_isempty(m->sysext_release), "sysextRelease", JSON_BUILD_STRV_ENV_PAIR(m->sysext_release)),
                                SD_JSON_BUILD_PAIR_CONDITION(!strv_isempty(m->confext_release), "confextRelease", JSON_BUILD_STRV_ENV_PAIR(m->confext_release)),
                                SD_JSON_BUILD_PAIR_BOOLEAN("useBootableUefi", dissected_image_is_bootable_uefi(m)),
                                SD_JSON_BUILD_PAIR_BOOLEAN("useBootableContainer", dissected_image_is_bootable_os(m)),
                                SD_JSON_BUILD_PAIR_BOOLEAN("useInitrd", dissected_image_is_initrd(m)),
                                SD_JSON_BUILD_PAIR_BOOLEAN("usePortableService", dissected_image_is_portable(m)),
                                SD_JSON_BUILD_PAIR_BOOLEAN("useSystemExtension", strv_contains(sysext_scopes, "system")),
                                SD_JSON_BUILD_PAIR_BOOLEAN("useInitRDSystemExtension", strv_contains(sysext_scopes, "initrd")),
                                SD_JSON_BUILD_PAIR_BOOLEAN("usePortableSystemExtension", strv_contains(sysext_scopes, "portable")),
                                SD_JSON_BUILD_PAIR_BOOLEAN("useConfigurationExtension", strv_contains(confext_scopes, "system")),
                                SD_JSON_BUILD_PAIR_BOOLEAN("useInitRDConfigurationExtension", strv_contains(confext_scopes, "initrd")),
                                SD_JSON_BUILD_PAIR_BOOLEAN("usePortableConfigurationExtension", strv_contains(confext_scopes, "portable")));
                if (r < 0)
                        return log_oom();
        }

        t = table_new("rw", "designator", "partition uuid", "partition label", "fstype", "architecture", "verity", "growfs", "node", "partno");
        if (!t)
                return log_oom();

        table_set_ersatz_string(t, TABLE_ERSATZ_DASH);
        (void) table_set_align_percent(t, table_get_cell(t, 0, 9), 100);

        /* Hide the device path if this is a loopback device that is not relinquished, since that means the
         * device node is not going to be useful the instant our command exits */
        if ((!d || d->created) && !sd_json_format_enabled(arg_json_format_flags))
                table_hide_column_from_display(t, 8);

        for (PartitionDesignator i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) {
                DissectedPartition *p = m->partitions + i;

                if (!p->found)
                        continue;

                r = table_add_many(
                                t,
                                TABLE_STRING, p->rw ? "rw" : "ro",
                                TABLE_STRING, partition_designator_to_string(i));
                if (r < 0)
                        return table_log_add_error(r);

                if (sd_id128_is_null(p->uuid))
                        r = table_add_cell(t, NULL, TABLE_EMPTY, NULL);
                else
                        r = table_add_cell(t, NULL, TABLE_UUID, &p->uuid);
                if (r < 0)
                        return table_log_add_error(r);

                r = table_add_many(
                                t,
                                TABLE_STRING, p->label,
                                TABLE_STRING, p->fstype,
                                TABLE_STRING, architecture_to_string(p->architecture));
                if (r < 0)
                        return table_log_add_error(r);

                if (arg_verity_settings.data_path)
                        r = table_add_cell(t, NULL, TABLE_STRING, "external");
                else if (dissected_image_verity_candidate(m, i))
                        r = table_add_cell(t, NULL, TABLE_STRING,
                                           dissected_image_verity_sig_ready(m, i) ? "signed" :
                                           yes_no(dissected_image_verity_ready(m, i)));
                else
                        r = table_add_cell(t, NULL, TABLE_EMPTY, NULL);
                if (r < 0)
                        return table_log_add_error(r);

                r = table_add_many(t, TABLE_BOOLEAN, (int) p->growfs);
                if (r < 0)
                        return table_log_add_error(r);

                if (p->partno < 0) /* no partition table, naked file system */ {
                        r = table_add_cell(t, NULL, TABLE_PATH_BASENAME, arg_image);
                        if (r < 0)
                                return table_log_add_error(r);

                        r = table_add_cell(t, NULL, TABLE_EMPTY, NULL);
                } else {
                        r = table_add_cell(t, NULL, TABLE_STRING, p->node);
                        if (r < 0)
                                return table_log_add_error(r);

                        r = table_add_cell(t, NULL, TABLE_INT, &p->partno);
                }
                if (r < 0)
                        return table_log_add_error(r);
        }

        if (!sd_json_format_enabled(arg_json_format_flags)) {
                table_set_header(t, arg_legend);

                r = table_print_or_warn(t);
                if (r < 0)
                        return r;
        } else {
                _cleanup_(sd_json_variant_unrefp) sd_json_variant *jt = NULL;

                r = table_to_json(t, &jt);
                if (r < 0)
                        return log_error_errno(r, "Failed to convert table to JSON: %m");

                r = sd_json_variant_set_field(&v, "mounts", jt);
                if (r < 0)
                        return log_oom();

                sd_json_variant_dump(v, arg_json_format_flags, stdout, NULL);
        }

        return 0;
}

static int action_mount(DissectedImage *m, LoopDevice *d) {
        int r;

        assert(m);
        assert(arg_action == ACTION_MOUNT);

        r = dissected_image_mount_and_warn(
                        m,
                        arg_path,
                        /* uid_shift= */ UID_INVALID,
                        /* uid_range= */ UID_INVALID,
                        /* userns_fd= */ -EBADF,
                        arg_flags);
        if (r < 0)
                return r;

        if (d) {
                r = loop_device_flock(d, LOCK_UN);
                if (r < 0)
                        return log_error_errno(r, "Failed to unlock loopback block device: %m");
        }

        r = dissected_image_relinquish(m);
        if (r < 0)
                return log_error_errno(r, "Failed to relinquish DM and loopback block devices: %m");

        return 0;
}

static int list_print_item(
                RecurseDirEvent event,
                const char *path,
                int dir_fd,
                int inode_fd,
                const struct dirent *de,
                const struct statx *sx,
                void *userdata) {

        assert(path);

        if (event == RECURSE_DIR_ENTER)
                printf("%s%s/%s\n", path, ansi_grey(), ansi_normal());
        else if (event == RECURSE_DIR_ENTRY)
                printf("%s\n", path);

        return RECURSE_DIR_CONTINUE;
}

static int get_file_sha256(int inode_fd, uint8_t ret[static SHA256_DIGEST_SIZE]) {
        _cleanup_close_ int fd = -EBADF;

        /* convert O_PATH fd into a regular one */
        fd = fd_reopen(inode_fd, O_RDONLY|O_CLOEXEC);
        if (fd < 0)
                return fd;

        /* Calculating the SHA sum might be slow, hence let's flush STDOUT first, to give user an idea where we are slow. */
        fflush(stdout);

        return sha256_fd(fd, UINT64_MAX, ret);
}

static const char *pick_color_for_uid_gid(uid_t uid) {
        if (uid == UID_NOBODY)
                return ansi_highlight_yellow4(); /* files should never be owned by 'nobody' (but might happen due to userns mapping) */
        if (uid_is_system(uid))
                return ansi_normal();            /* files in disk images are typically owned by root and other system users, no issue there */
        if (uid_is_dynamic(uid) || uid_is_greeter(uid))
                return ansi_highlight_red();     /* files should never be owned persistently by dynamic users, and there are just no excuses */
        if (uid_is_container(uid) || uid_is_foreign(uid))
                return ansi_highlight_cyan();

        return ansi_highlight();
}

static int mtree_print_item(
                RecurseDirEvent event,
                const char *path,
                int dir_fd,
                int inode_fd,
                const struct dirent *de,
                const struct statx *sx,
                void *userdata) {

        _cleanup_free_ char *escaped = NULL;
        int r;

        assert(path);

        if (!IN_SET(event, RECURSE_DIR_ENTER, RECURSE_DIR_ENTRY))
                return RECURSE_DIR_CONTINUE;

        assert(sx);

        if (isempty(path))
                path = ".";
        else {
                /* BSD mtree uses either C or octal escaping, and covers whitespace, comments and glob characters. We use C style escaping and follow suit */
                path = escaped = xescape(path, WHITESPACE COMMENTS GLOB_CHARS);
                if (!escaped)
                        return log_oom();
        }

        printf("%s", isempty(path) ? "." : path);

        if (FLAGS_SET(sx->stx_mask, STATX_TYPE)) {
                if (S_ISDIR(sx->stx_mode))
                        printf("%s/%s", ansi_grey(), ansi_normal());

                printf(" %stype=%s%s%s%s",
                       ansi_grey(),
                       ansi_normal(),
                       S_ISDIR(sx->stx_mode) ? ansi_highlight_blue() :
                       S_ISLNK(sx->stx_mode) ? ansi_highlight_cyan() :
                       (S_ISFIFO(sx->stx_mode) || S_ISCHR(sx->stx_mode) || S_ISBLK(sx->stx_mode)) ? ansi_highlight_yellow4() :
                       S_ISSOCK(sx->stx_mode) ? ansi_highlight_magenta() : "",
                       ASSERT_PTR(S_ISDIR(sx->stx_mode) ? "dir" :
                                  S_ISREG(sx->stx_mode) ? "file" :
                                  S_ISLNK(sx->stx_mode) ? "link" :
                                  S_ISFIFO(sx->stx_mode) ? "fifo" :
                                  S_ISBLK(sx->stx_mode) ? "block" :
                                  S_ISCHR(sx->stx_mode) ? "char" :
                                  S_ISSOCK(sx->stx_mode) ? "socket" : NULL),
                       ansi_normal());
        }

        if (FLAGS_SET(sx->stx_mask, STATX_MODE) && (!FLAGS_SET(sx->stx_mask, STATX_TYPE) || !S_ISLNK(sx->stx_mode)))
                printf(" %smode=%s%04o",
                       ansi_grey(),
                       ansi_normal(),
                       (unsigned) (sx->stx_mode & 0777));

        if (FLAGS_SET(sx->stx_mask, STATX_UID))
                printf(" %suid=%s" UID_FMT "%s",
                       ansi_grey(),
                       pick_color_for_uid_gid(sx->stx_uid),
                       sx->stx_uid,
                       ansi_normal());

        if (FLAGS_SET(sx->stx_mask, STATX_GID))
                printf(" %sgid=%s" GID_FMT "%s",
                       ansi_grey(),
                       pick_color_for_uid_gid(sx->stx_gid),
                       sx->stx_gid,
                       ansi_normal());

        if (FLAGS_SET(sx->stx_mask, STATX_TYPE|STATX_SIZE) && S_ISREG(sx->stx_mode)) {
                printf(" %ssize=%s%" PRIu64,
                       ansi_grey(),
                       ansi_normal(),
                       (uint64_t) sx->stx_size);

                if (arg_mtree_hash && inode_fd >= 0 && sx->stx_size > 0) {
                        uint8_t hash[SHA256_DIGEST_SIZE];

                        r = get_file_sha256(inode_fd, hash);
                        if (r < 0)
                                log_warning_errno(r, "Failed to calculate file SHA256 sum for '%s', ignoring: %m", path);
                        else {
                                _cleanup_free_ char *h = NULL;

                                h = hexmem(hash, sizeof(hash));
                                if (!h)
                                        return log_oom();

                                printf(" %ssha256sum=%s%s",
                                       ansi_grey(),
                                       ansi_normal(),
                                       h);
                        }
                }
        }

        if (FLAGS_SET(sx->stx_mask, STATX_TYPE) && S_ISLNK(sx->stx_mode) && inode_fd >= 0) {
                _cleanup_free_ char *target = NULL;

                r = readlinkat_malloc(inode_fd, "", &target);
                if (r < 0)
                        log_warning_errno(r, "Failed to read symlink '%s', ignoring: %m", path);
                else {
                        _cleanup_free_ char *target_escaped = NULL;

                        target_escaped = xescape(target, WHITESPACE COMMENTS GLOB_CHARS);
                        if (!target_escaped)
                                return log_oom();

                        printf(" %slink=%s%s",
                               ansi_grey(),
                               ansi_normal(),
                               target_escaped);
                }
        }

        if (FLAGS_SET(sx->stx_mask, STATX_TYPE) && (S_ISBLK(sx->stx_mode) || S_ISCHR(sx->stx_mode)))
                printf(" %sdevice=%slinux,%" PRIu64 ",%" PRIu64,
                       ansi_grey(),
                       ansi_normal(),
                       (uint64_t) sx->stx_rdev_major,
                       (uint64_t) sx->stx_rdev_minor);

        printf("\n");

        return RECURSE_DIR_CONTINUE;
}

static int action_list_or_mtree_or_copy_or_make_archive(DissectedImage *m, LoopDevice *d, int userns_fd) {
        _cleanup_(umount_and_freep) char *mounted_dir = NULL;
        _cleanup_free_ char *t = NULL;
        const char *root;
        int r;

        assert(IN_SET(arg_action, ACTION_LIST, ACTION_MTREE, ACTION_COPY_FROM, ACTION_COPY_TO, ACTION_MAKE_ARCHIVE, ACTION_SHIFT));

        /* Determine whether to copy ownership:
         * --copy-ownership=yes: always try to preserve ownership
         *  --copy-ownership=no: never preserve ownership, use current user
         *              default: preserve ownership for directory trees,
         *                       but not for regular files (since DDI password tables are typically
         *                       distinct from the host ones, individual file ownership is less meaningful) */

        if (arg_image) {
                assert(m);

                if (userns_fd < 0)
                        r = detach_mount_namespace_harder(0, 0);
                else
                        r = detach_mount_namespace_userns(userns_fd);
                if (r < 0)
                        return log_error_errno(r, "Failed to detach mount namespace: %m");

                /* Create a place we can mount things onto soon. We use a fixed path shared by all invocations. Given
                 * the mounts are done in a mount namespace there's not going to be a collision here */
                r = get_common_dissect_directory(&t);
                if (r < 0)
                        return log_error_errno(r, "Failed to generate private mount directory: %m");

                r = dissected_image_mount_and_warn(
                                m,
                                t,
                                /* uid_shift= */ UID_INVALID,
                                /* uid_range= */ UID_INVALID,
                                /* userns_fd= */ -EBADF,
                                arg_flags);
                if (r < 0)
                        return r;

                root = mounted_dir = TAKE_PTR(t);

                if (d) {
                        r = loop_device_flock(d, LOCK_UN);
                        if (r < 0)
                                return log_error_errno(r, "Failed to unlock loopback block device: %m");
                }

                r = dissected_image_relinquish(m);
                if (r < 0)
                        return log_error_errno(r, "Failed to relinquish DM and loopback block devices: %m");

                dissected_image_close(m);
        } else
                root = arg_root;

        switch (arg_action) {

        case ACTION_COPY_FROM: {
                _cleanup_close_ int source_fd = -EBADF, target_fd = -EBADF;

                source_fd = chase_and_open(arg_source, root, CHASE_PREFIX_ROOT|CHASE_WARN, O_RDONLY|O_CLOEXEC|O_NOCTTY, NULL);
                if (source_fd < 0)
                        return log_error_errno(source_fd, "Failed to open source path '%s' in image '%s': %m", arg_source, arg_image);

                /* Copying to stdout? */
                if (streq(arg_target, "-")) {
                        r = copy_bytes(source_fd, STDOUT_FILENO, UINT64_MAX, COPY_REFLINK);
                        if (r < 0)
                                return log_error_errno(r, "Failed to copy bytes from %s in mage '%s' to stdout: %m", arg_source, arg_image);

                        /* When we copy to stdout we don't copy any attributes (i.e. no access mode, no ownership, no xattr, no times) */
                        return 0;
                }

                /* Try to copy as directory? */
                r = copy_directory_at(
                                source_fd, /* from= */ NULL,
                                AT_FDCWD, arg_target,
                                arg_copy_ownership == 0 ? getuid() : UID_INVALID,
                                arg_copy_ownership == 0 ? getgid() : GID_INVALID,
                                COPY_REFLINK|COPY_MERGE|COPY_REPLACE|COPY_SIGINT|COPY_HARDLINKS);
                if (r >= 0)
                        return 0;
                if (r != -ENOTDIR)
                        return log_error_errno(r, "Failed to copy %s in image '%s' to '%s': %m", arg_source, arg_image, arg_target);

                r = fd_verify_regular(source_fd);
                if (r == -EISDIR)
                        return log_error_errno(r, "Target '%s' exists already and is not a directory.", arg_target);
                if (r < 0)
                        return log_error_errno(r, "Source path %s in image '%s' is neither regular file nor directory, refusing: %m", arg_source, arg_image);

                /* Nah, it's a plain file! */
                target_fd = open(arg_target, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0600);
                if (target_fd < 0)
                        return log_error_errno(errno, "Failed to create regular file at target path '%s': %m", arg_target);

                r = copy_bytes(source_fd, target_fd, UINT64_MAX, COPY_REFLINK);
                if (r < 0)
                        return log_error_errno(r, "Failed to copy bytes from %s in mage '%s' to '%s': %m", arg_source, arg_image, arg_target);

                (void) copy_xattr(source_fd, NULL, target_fd, NULL, 0);
                (void) copy_access(source_fd, target_fd);
                if (arg_copy_ownership > 0)
                        (void) copy_owner(source_fd, target_fd);
                (void) copy_times(source_fd, target_fd, 0);

                return 0;
        }

        case ACTION_COPY_TO: {
                _cleanup_close_ int source_fd = -EBADF, target_fd = -EBADF, dfd = -EBADF;
                _cleanup_free_ char *dn = NULL, *bn = NULL;
                bool is_dir;

                r = path_extract_directory(arg_target, &dn);
                if (r < 0)
                        return log_error_errno(r, "Failed to extract directory from target path '%s': %m", arg_target);
                r = path_extract_filename(arg_target, &bn);
                if (r < 0)
                        return log_error_errno(r, "Failed to extract filename from target path '%s': %m", arg_target);
                is_dir = r == O_DIRECTORY;

                r = chase(dn, root, CHASE_PREFIX_ROOT|CHASE_WARN, NULL, &dfd);
                if (r < 0)
                        return log_error_errno(r, "Failed to open '%s': %m", dn);

                /* Are we reading from stdin? */
                if (streq(arg_source, "-")) {
                        if (is_dir)
                                return log_error_errno(SYNTHETIC_ERRNO(EISDIR), "Cannot copy STDIN to a directory, refusing.");

                        target_fd = openat(dfd, bn, O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY|O_EXCL, 0644);
                        if (target_fd < 0)
                                return log_error_errno(errno, "Failed to open target file '%s': %m", arg_target);

                        r = copy_bytes(STDIN_FILENO, target_fd, UINT64_MAX, COPY_REFLINK);
                        if (r < 0)
                                return log_error_errno(r, "Failed to copy bytes from stdin to '%s' in image '%s': %m", arg_target, arg_image);

                        /* When we copy from stdin we don't copy any attributes (i.e. no access mode, no ownership, no xattr, no times) */
                        return 0;
                }

                source_fd = open(arg_source, O_RDONLY|O_CLOEXEC|O_NOCTTY);
                if (source_fd < 0)
                        return log_error_errno(source_fd, "Failed to open source path '%s': %m", arg_source);

                r = fd_verify_regular(source_fd);
                if (r < 0) {
                        if (r != -EISDIR)
                                return log_error_errno(r, "Source '%s' is neither regular file nor directory: %m", arg_source);

                        /* We are looking at a directory. */

                        target_fd = openat(dfd, bn, O_RDONLY|O_DIRECTORY|O_CLOEXEC);
                        if (target_fd < 0) {
                                if (errno != ENOENT)
                                        return log_error_errno(errno, "Failed to open destination '%s': %m", arg_target);

                                r = copy_tree_at(
                                                source_fd, ".",
                                                dfd, bn,
                                                arg_copy_ownership == 0 ? getuid() : UID_INVALID,
                                                arg_copy_ownership == 0 ? getgid() : GID_INVALID,
                                                COPY_REFLINK|COPY_MERGE|COPY_REPLACE|COPY_SIGINT|COPY_HARDLINKS,
                                                /* denylist= */ NULL,
                                                /* subvolumes= */ NULL);
                        } else
                                r = copy_tree_at(
                                                source_fd, ".",
                                                target_fd, ".",
                                                arg_copy_ownership == 0 ? getuid() : UID_INVALID,
                                                arg_copy_ownership == 0 ? getgid() : GID_INVALID,
                                                COPY_REFLINK|COPY_MERGE|COPY_REPLACE|COPY_SIGINT|COPY_HARDLINKS,
                                                /* denylist= */ NULL,
                                                /* subvolumes= */ NULL);
                        if (r < 0)
                                return log_error_errno(r, "Failed to copy '%s' to '%s' in image '%s': %m", arg_source, arg_target, arg_image);

                        return 0;
                }

                if (is_dir)
                        return log_error_errno(SYNTHETIC_ERRNO(EISDIR), "Source is a regular file, but target is not, refusing.");

                /* We area looking at a regular file */
                target_fd = openat(dfd, bn, O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY|O_EXCL, 0600);
                if (target_fd < 0)
                        return log_error_errno(errno, "Failed to open target file '%s': %m", arg_target);

                r = copy_bytes(source_fd, target_fd, UINT64_MAX, COPY_REFLINK);
                if (r < 0)
                        return log_error_errno(r, "Failed to copy bytes from '%s' to '%s' in image '%s': %m", arg_source, arg_target, arg_image);

                (void) copy_xattr(source_fd, NULL, target_fd, NULL, 0);
                (void) copy_access(source_fd, target_fd);
                if (arg_copy_ownership > 0)
                        (void) copy_owner(source_fd, target_fd);
                (void) copy_times(source_fd, target_fd, 0);

                return 0;
        }

        case ACTION_LIST:
        case ACTION_MTREE: {
                _cleanup_close_ int dfd = -EBADF;

                dfd = open(root, O_DIRECTORY|O_CLOEXEC|O_RDONLY);
                if (dfd < 0)
                        return log_error_errno(errno, "Failed to open mount directory: %m");

                pager_open(arg_pager_flags);

                if (arg_action == ACTION_LIST)
                        r = recurse_dir(dfd, NULL, 0, UINT_MAX, RECURSE_DIR_SORT, list_print_item, NULL);
                else if (arg_action == ACTION_MTREE)
                        r = recurse_dir(dfd, ".", STATX_TYPE|STATX_MODE|STATX_UID|STATX_GID|STATX_SIZE, UINT_MAX, RECURSE_DIR_SORT|RECURSE_DIR_INODE_FD|RECURSE_DIR_TOPLEVEL, mtree_print_item, NULL);
                else
                        assert_not_reached();
                if (r < 0)
                        return log_error_errno(r, "Failed to list image: %m");
                return 0;
        }

        case ACTION_MAKE_ARCHIVE: {
#if HAVE_LIBARCHIVE
                _cleanup_close_ int dfd = -EBADF;

                dfd = open(root, O_DIRECTORY|O_CLOEXEC|O_RDONLY);
                if (dfd < 0)
                        return log_error_errno(errno, "Failed to open mount directory: %m");

                _cleanup_(unlink_and_freep) char *tar = NULL;
                _cleanup_close_ int tmp_fd = -EBADF;
                int output_fd;
                if (arg_target) {
                        tmp_fd = open_tmpfile_linkable(arg_target, O_WRONLY|O_CLOEXEC, &tar);
                        if (tmp_fd < 0)
                                return log_error_errno(tmp_fd, "Failed to create target file '%s': %m", arg_target);

                        output_fd = tmp_fd;
                } else {
                        if (isatty_safe(STDOUT_FILENO))
                                return log_error_errno(SYNTHETIC_ERRNO(EBADF), "Refusing to write archive to TTY.");

                        output_fd = STDOUT_FILENO;
                }

                r = tar_c(dfd, output_fd, arg_target, /* flags= */ 0);
                if (r < 0)
                        return r;

                if (arg_target) {
                        r = link_tmpfile(tmp_fd, tar, arg_target, LINK_TMPFILE_REPLACE);
                        if (r < 0)
                                return log_error_errno(r, "Failed to move archive file into place: %m");

                        tar = mfree(tar);
                }

                return 0;
#else
                assert_not_reached();
#endif
        }

        case ACTION_SHIFT:
                r = path_patch_uid(root, arg_uid_base, 0x10000);
                if (r < 0)
                        return log_error_errno(r, "Failed to shift UID base: %m");

                return 0;

        default:
                assert_not_reached();
        }
}

static int action_umount(const char *path) {
        _cleanup_close_ int fd = -EBADF;
        _cleanup_free_ char *canonical = NULL;
        _cleanup_(loop_device_unrefp) LoopDevice *d = NULL;
        _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
        int r;

        fd = chase_and_open(path, NULL, 0, O_DIRECTORY, &canonical);
        if (fd == -ENOTDIR)
                return log_error_errno(SYNTHETIC_ERRNO(ENOTDIR), "'%s' is not a directory", path);
        if (fd < 0)
                return log_error_errno(fd, "Failed to resolve path '%s': %m", path);

        r = is_mount_point_at(fd, NULL, 0);
        if (r == 0)
                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "'%s' is not a mount point", canonical);
        if (r < 0)
                return log_error_errno(r, "Failed to determine whether '%s' is a mount point: %m", canonical);

        r = block_device_new_from_fd(fd, BLOCK_DEVICE_LOOKUP_WHOLE_DISK | BLOCK_DEVICE_LOOKUP_BACKING, &dev);
        if (r < 0) {
                _cleanup_close_ int usr_fd = -EBADF;

                /* The command `systemd-dissect --mount` expects that the image at least has the root or /usr
                 * partition. If it does not have the root partition, then we mount the /usr partition on a
                 * tmpfs. Hence, let's try to find the backing block device through the /usr partition. */

                usr_fd = openat(fd, "usr", O_CLOEXEC | O_DIRECTORY | O_NOFOLLOW);
                if (usr_fd < 0)
                        return log_error_errno(errno, "Failed to open '%s/usr': %m", canonical);

                r = block_device_new_from_fd(usr_fd, BLOCK_DEVICE_LOOKUP_WHOLE_DISK | BLOCK_DEVICE_LOOKUP_BACKING, &dev);
        }
        if (r < 0)
                return log_error_errno(r, "Failed to find backing block device for '%s': %m", canonical);

        r = loop_device_open(dev, 0, LOCK_EX, &d);
        if (r < 0) {
                if (!ERRNO_IS_PRIVILEGE(r))
                        return log_device_error_errno(dev, r, "Failed to open loopback block device: %m");

                log_device_debug_errno(dev, r, "Lacking privileges to open loopback block device, ignoring.");
        }

        /* We've locked the loop device, now we're ready to unmount. To allow the unmount to succeed, we have
         * to close the O_PATH fd we opened earlier. */
        fd = safe_close(fd);

        r = umount_recursive(canonical, 0);
        if (r < 0)
                return log_error_errno(r, "Failed to unmount '%s': %m", canonical);

        /* We managed to lock and unmount successfully? That means we can try to remove the loop device. */
        if (d)
                loop_device_unrelinquish(d);

        if (arg_rmdir) {
                r = RET_NERRNO(rmdir(canonical));
                if (r < 0)
                        return log_error_errno(r, "Failed to remove mount directory '%s': %m", canonical);
        }

        return 0;
}

static int action_with(DissectedImage *m, LoopDevice *d) {
        _cleanup_(umount_and_rmdir_and_freep) char *mounted_dir = NULL;
        _cleanup_(rmdir_and_freep) char *created_dir = NULL;
        _cleanup_free_ char *temp = NULL;
        int r, rcode;

        assert(m);
        assert(arg_action == ACTION_WITH);

        r = tempfn_random_child(NULL, program_invocation_short_name, &temp);
        if (r < 0)
                return log_error_errno(r, "Failed to generate temporary mount directory: %m");

        r = mkdir_p(temp, 0700);
        if (r < 0)
                return log_error_errno(r, "Failed to create mount point: %m");

        created_dir = TAKE_PTR(temp);

        r = dissected_image_mount_and_warn(
                        m,
                        created_dir,
                        /* uid_shift= */ UID_INVALID,
                        /* uid_range= */ UID_INVALID,
                        /* userns_fd= */ -EBADF,
                        arg_flags);
        if (r < 0)
                return r;

        mounted_dir = TAKE_PTR(created_dir);

        r = dissected_image_relinquish(m);
        if (r < 0)
                return log_error_errno(r, "Failed to relinquish DM and loopback block devices: %m");

        if (d) {
                r = loop_device_flock(d, LOCK_UN);
                if (r < 0)
                        return log_error_errno(r, "Failed to unlock loopback block device: %m");
        }

        rcode = pidref_safe_fork("(with)", FORK_CLOSE_ALL_FDS|FORK_LOG|FORK_REOPEN_LOG|FORK_WAIT, /* ret= */ NULL);
        if (rcode == 0) {
                /* Child */

                if (chdir(mounted_dir) < 0) {
                        log_error_errno(errno, "Failed to change to '%s' directory: %m", mounted_dir);
                        _exit(EXIT_FAILURE);
                }

                if (setenv("SYSTEMD_DISSECT_ROOT", mounted_dir, /* overwrite= */ true) < 0) {
                        log_error_errno(errno, "Failed to set $SYSTEMD_DISSECT_ROOT: %m");
                        _exit(EXIT_FAILURE);
                }

                if (d && setenv("SYSTEMD_DISSECT_DEVICE", d->node, /* overwrite= */ true) < 0) {
                        log_error_errno(errno, "Failed to set $SYSTEMD_DISSECT_DEVICE: %m");
                        _exit(EXIT_FAILURE);
                }

                if (strv_isempty(arg_argv)) {
                        const char *sh;

                        sh = secure_getenv("SHELL");
                        if (sh) {
                                execvp(sh, STRV_MAKE(sh));
                                log_warning_errno(errno, "Failed to execute $SHELL, falling back to /bin/sh: %m");
                        }

                        execl("/bin/sh", "sh", NULL);
                        log_error_errno(errno, "Failed to invoke /bin/sh: %m");
                } else {
                        execvp(arg_argv[0], arg_argv);
                        log_error_errno(errno, "Failed to execute '%s': %m", arg_argv[0]);
                }

                _exit(EXIT_FAILURE);
        }

        /* Let's manually detach everything, to make things synchronous */
        if (d) {
                r = loop_device_flock(d, LOCK_SH);
                if (r < 0)
                        log_warning_errno(r, "Failed to lock loopback block device, ignoring: %m");
        }

        r = umount_recursive(mounted_dir, 0);
        if (r < 0)
                log_warning_errno(r, "Failed to unmount '%s', ignoring: %m", mounted_dir);
        else if (d)
                loop_device_unrelinquish(d); /* Let's try to destroy the loopback device */

        created_dir = TAKE_PTR(mounted_dir);

        if (rmdir(created_dir) < 0)
                log_warning_errno(errno, "Failed to remove directory '%s', ignoring: %m", created_dir);

        temp = TAKE_PTR(created_dir);

        return rcode;
}

static int action_discover(void) {
        _cleanup_hashmap_free_ Hashmap *images = NULL;
        int r;

        for (ImageClass cl = 0; cl < _IMAGE_CLASS_MAX; cl++) {
                r = image_discover(arg_runtime_scope, cl, NULL, &images);
                if (r < 0)
                        return log_error_errno(r, "Failed to discover images: %m");
        }

        if (hashmap_isempty(images) && !sd_json_format_enabled(arg_json_format_flags)) {
                log_info("No images found.");
                return 0;
        }

        _cleanup_(table_unrefp) Table *t = table_new("name", "type", "class", "ro", "path", "time", "usage");
        if (!t)
                return log_oom();

        table_set_align_percent(t, table_get_cell(t, 0, 6), 100);
        table_set_ersatz_string(t, TABLE_ERSATZ_DASH);

        Image *img;
        HASHMAP_FOREACH(img, images) {

                if (!arg_all && startswith(img->name, "."))
                        continue;

                r = table_add_many(
                                t,
                                TABLE_STRING, img->name,
                                TABLE_SET_COLOR, startswith(img->name, ".") ? ANSI_GREY : NULL,
                                TABLE_STRING, image_type_to_string(img->type),
                                TABLE_STRING, image_class_to_string(img->class),
                                TABLE_BOOLEAN, image_is_read_only(img),
                                TABLE_SET_COLOR, image_is_read_only(img) ? ANSI_HIGHLIGHT_RED : ANSI_HIGHLIGHT_GREEN,
                                TABLE_PATH, img->path,
                                TABLE_TIMESTAMP, img->mtime != 0 ? img->mtime : img->crtime,
                                TABLE_SIZE, img->usage,
                                TABLE_SET_COLOR, img->usage <= 0 ? ANSI_HIGHLIGHT_RED : NULL);
                if (r < 0)
                        return table_log_add_error(r);
        }

        (void) table_set_sort(t, (size_t) 0);

        return table_print_with_pager(t, arg_json_format_flags, arg_pager_flags, arg_legend);
}

static int action_attach(DissectedImage *m, LoopDevice *d) {
        int r;

        assert(m);
        assert(d);

        r = loop_device_set_autoclear(d, false);
        if (r < 0)
                return log_error_errno(r, "Failed to disable auto-clear logic on loopback device: %m");

        r = dissected_image_relinquish(m);
        if (r < 0)
                return log_error_errno(r, "Failed to relinquish DM and loopback block devices: %m");

        if (!arg_quiet)
                puts(d->node);

        return 0;
}

static int action_detach(const char *path) {
        _cleanup_(loop_device_unrefp) LoopDevice *loop = NULL;
        _cleanup_close_ int fd = -EBADF;
        struct stat st;
        int r;

        assert(path);

        fd = open(path, O_PATH|O_CLOEXEC);
        if (fd < 0)
                return log_error_errno(errno, "Failed to open '%s': %m", path);

        if (fstat(fd, &st) < 0)
                return log_error_errno(errno, "Failed to stat '%s': %m", path);

        if (S_ISBLK(st.st_mode)) {
                r = loop_device_open_from_fd(fd, O_RDONLY, LOCK_EX, &loop);
                if (r < 0)
                        return log_error_errno(r, "Failed to open '%s' as loopback block device: %m", path);

        } else if (S_ISREG(st.st_mode)) {
                _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;

                /* If a regular file is specified, search for a loopback block device that is backed by it */

                r = sd_device_enumerator_new(&e);
                if (r < 0)
                        return log_error_errno(r, "Failed to allocate enumerator: %m");

                r = sd_device_enumerator_add_match_subsystem(e, "block", true);
                if (r < 0)
                        return log_error_errno(r, "Failed to match block devices: %m");

                r = sd_device_enumerator_add_match_sysname(e, "loop*");
                if (r < 0)
                        return log_error_errno(r, "Failed to match loopback block devices: %m");

                (void) sd_device_enumerator_allow_uninitialized(e);

                FOREACH_DEVICE(e, d) {
                        _cleanup_(loop_device_unrefp) LoopDevice *entry_loop = NULL;

                        r = device_is_devtype(d, "disk");
                        if (r < 0) {
                                log_device_warning_errno(d, r, "Failed to check if device is a whole disk, skipping: %m");
                                continue;
                        }
                        if (r == 0)
                                continue; /* Filter out partition block devices */

                        r = loop_device_open(d, O_RDONLY, LOCK_SH, &entry_loop);
                        if (r < 0) {
                                log_device_warning_errno(d, r, "Failed to open loopback block device, skipping: %m");
                                continue;
                        }

                        if (entry_loop->backing_devno == st.st_dev && entry_loop->backing_inode == st.st_ino) {
                                /* Found it! The kernel allows attaching a single file to multiple loopback
                                 * devices. Let's destruct them in reverse order, i.e. find the last matching
                                 * loopback device here, rather than the first. */

                                loop_device_unref(loop);
                                loop = TAKE_PTR(entry_loop);
                        }
                }

                if (!loop)
                        return log_error_errno(SYNTHETIC_ERRNO(ENXIO), "No loopback block device backed by '%s' found.", path);

                r = loop_device_flock(loop, LOCK_EX);
                if (r < 0)
                        return log_error_errno(r, "Failed to upgrade device lock: %m");
        }

        r = loop_device_set_autoclear(loop, true);
        if (r < 0)
                log_warning_errno(r, "Failed to enable autoclear logic on '%s', ignoring: %m", loop->node);

        loop_device_unrelinquish(loop);
        return 0;
}

static int action_validate(void) {
        int r;

        r = dissect_image_file_and_warn(
                        arg_image,
                        &arg_verity_settings,
                        /* mount_options= */ NULL,
                        arg_image_policy,
                        arg_image_filter,
                        arg_flags,
                        /* ret= */ NULL);
        if (r < 0)
                return r;

        if (isatty_safe(STDOUT_FILENO) && emoji_enabled())
                printf("%s ", glyph(GLYPH_SPARKLES));

        printf("%sOK%s", ansi_highlight_green(), ansi_normal());

        if (isatty_safe(STDOUT_FILENO) && emoji_enabled())
                printf(" %s", glyph(GLYPH_SPARKLES));

        putc('\n', stdout);
        return 0;
}

static int run(int argc, char *argv[]) {
        _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL;
        _cleanup_(loop_device_unrefp) LoopDevice *d = NULL;
        _cleanup_close_ int userns_fd = -EBADF;
        int r;

        log_setup();

        if (invoked_as(argv, "mount.ddi"))
                r = parse_argv_as_mount_helper(argc, argv);
        else
                r = parse_argv(argc, argv);
        if (r <= 0)
                return r;

        if (arg_image) {
                r = path_pick_update_warn(
                                &arg_image,
                                pick_filter_image_raw,
                                ELEMENTSOF(pick_filter_image_raw),
                                PICK_ARCHITECTURE|PICK_TRIES,
                                /* ret_result= */ NULL);
                if (r < 0)
                        return r;
        }

        if (arg_root) {
                r = path_pick_update_warn(
                                &arg_root,
                                pick_filter_image_dir,
                                ELEMENTSOF(pick_filter_image_dir),
                                PICK_ARCHITECTURE|PICK_TRIES,
                                /* ret_result= */ NULL);
                if (r < 0)
                        return r;
        }

        switch (arg_action) {
        case ACTION_UMOUNT:
                return action_umount(arg_path);

        case ACTION_DETACH:
                return action_detach(arg_image);

        case ACTION_DISCOVER:
                return action_discover();

        default:
                /* All other actions need the image dissected (except for ACTION_VALIDATE, see below) */
                ;
        }

        if (arg_image) {
                r = verity_settings_load(
                                &arg_verity_settings,
                                arg_image,
                                /* root_hash_path= */ NULL,
                                /* root_hash_sig_path= */ NULL);
                if (r < 0)
                        return log_error_errno(r, "Failed to read verity artifacts for %s: %m", arg_image);

                if (arg_verity_settings.data_path)
                        arg_flags |= DISSECT_IMAGE_NO_PARTITION_TABLE; /* We only support Verity per file system,
                                                                        * hence if there's external Verity data
                                                                        * available we turn off partition table
                                                                        * support */
        }

        if (!arg_loop_ref && arg_loop_ref_auto) {
                r = path_extract_filename(arg_image, &arg_loop_ref);
                if (r < 0)
                        return log_error_errno(r, "Failed to extract file name from image path '%s': %m", arg_image);
        }

        if (arg_action == ACTION_VALIDATE)
                return action_validate();

        if (arg_image) {
                /* First try locally, if we are allowed to */
                if (!arg_via_service) {
                        uint32_t loop_flags;
                        int open_flags;

                        open_flags = FLAGS_SET(arg_flags, DISSECT_IMAGE_DEVICE_READ_ONLY) ? O_RDONLY : -1;
                        loop_flags = FLAGS_SET(arg_flags, DISSECT_IMAGE_NO_PARTITION_TABLE) ? 0 : LO_FLAGS_PARTSCAN;
                        /* --attach hands a loop device to the user, who may populate it with a (nested)
                         * partition table afterwards, so force a real loopback device with partition
                         * scanning even if the image is currently unpartitioned. */
                        if (arg_action == ACTION_ATTACH)
                                loop_flags |= LOOP_DEVICE_MAY_POPULATE_PARTITION_TABLE;

                        if (arg_in_memory)
                                r = loop_device_make_by_path_memory(arg_image, open_flags, /* sector_size= */ UINT32_MAX, loop_flags, LOCK_SH, &d);
                        else
                                r = loop_device_make_by_path(arg_image, open_flags, /* sector_size= */ UINT32_MAX, loop_flags, LOCK_SH, &d);
                        if (r < 0) {
                                if ((r != -ENOENT && !ERRNO_IS_PRIVILEGE(r)) || arg_action == ACTION_ATTACH)
                                        return log_error_errno(r, "Failed to set up loopback device for %s: %m", arg_image);

                                log_debug_errno(r, "Lacking permissions or missing /dev/loop-control to set up loopback block device for %s, using service: %m", arg_image);
                                arg_via_service = true;
                        } else {
                                if (arg_loop_ref && !LOOP_DEVICE_IS_FOREIGN(d)) {
                                        r = loop_device_set_filename(d, arg_loop_ref);
                                        if (r < 0)
                                                log_warning_errno(r, "Failed to set loop reference string to '%s', ignoring: %m", arg_loop_ref);
                                }

                                r = dissect_loop_device_and_warn(
                                                d,
                                                &arg_verity_settings,
                                                /* mount_options= */ NULL,
                                                arg_image_policy,
                                                arg_image_filter,
                                                arg_flags,
                                                &m);
                                if (r < 0)
                                        return r;

                                if (arg_action == ACTION_ATTACH)
                                        return action_attach(m, d);

                                r = dissected_image_load_verity_sig_partition(
                                                m,
                                                d->fd,
                                                &arg_verity_settings);
                                if (r < 0)
                                        return log_error_errno(r, "Failed to load verity signature partition: %m");

                                r = dissected_image_guess_verity_roothash(
                                                m,
                                                &arg_verity_settings);
                                if (r < 0)
                                        return log_error_errno(r, "Failed to guess verity root hash: %m");

                                if (arg_action != ACTION_DISSECT) {
                                        _cleanup_(erase_and_freep) char *envpw = NULL;

                                        r = getenv_steal_erase("PASSWORD", &envpw);
                                        if (r < 0)
                                                return log_error_errno(r, "Failed to acquire password from environment: %m");

                                        r = dissected_image_decrypt_interactively(
                                                        m,
                                                        envpw,
                                                        &arg_verity_settings,
                                                        arg_image_policy,
                                                        arg_flags);
                                        if (r < 0)
                                                return r;
                                }
                        }
                }

                /* Try via service */
                if (arg_via_service) {
                        if (arg_in_memory)
                                return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "--in-memory= not supported when operating via systemd-mountfsd.");

                        if (arg_loop_ref || arg_loop_ref_auto) /* yes, the 2nd check is strictly speaking redundant, given the normalization we did above, but let's be explicit here */
                                return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "--loop-ref=/--loop-ref-auto not supported when operating via systemd-mountfsd.");

                        /* Don't run things in private userns, if the mount shall be attached to the host
                         * or if we're copying from/to the host. */
                        if (!IN_SET(arg_action, ACTION_MOUNT, ACTION_WITH, ACTION_COPY_FROM, ACTION_COPY_TO)) {
                                userns_fd = nsresource_allocate_userns(
                                                /* vl= */ NULL,
                                                /* name= */ NULL,
                                                NSRESOURCE_UIDS_64K); /* allocate 64K users by default */
                                if (userns_fd < 0)
                                        return log_error_errno(userns_fd, "Failed to allocate user namespace with 64K users: %m");
                        }

                        r = mountfsd_mount_image(
                                        /* vl= */ NULL,
                                        arg_image,
                                        userns_fd,
                                        /* options= */ NULL,
                                        arg_image_policy,
                                        &arg_verity_settings,
                                        arg_flags,
                                        &m);
                        if (r < 0)
                                return log_error_errno(r, "Failed to mount image via mountfsd: %m");
                }
        }

        switch (arg_action) {

        case ACTION_DISSECT:
                return action_dissect(m, d, userns_fd);

        case ACTION_MOUNT:
                return action_mount(m, d);

        case ACTION_LIST:
        case ACTION_MTREE:
        case ACTION_COPY_FROM:
        case ACTION_COPY_TO:
        case ACTION_MAKE_ARCHIVE:
        case ACTION_SHIFT:
                return action_list_or_mtree_or_copy_or_make_archive(m, d, userns_fd);

        case ACTION_WITH:
                return action_with(m, d);

        default:
                assert_not_reached();
        }
}

DEFINE_MAIN_FUNCTION(run);
