machine: add support for importing containers from plain directories

Fixes: #2728

This is also supposed to be preparation for doing #10234 eventually,
where a very similar operation is requested: instead of importing a tree
to /var/lib/machines it would need to be imported into
/var/lib/portables/.

1 files changed, 323 insertions, 0 deletions

diff --git a/src/import/import-fs.c b/src/import/import-fs.c
new file mode 100644
index 0000000000..3836f87570
--- /dev/null
+++ b/src/import/import-fs.c
@@ -0,0 +1,323 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <getopt.h>
+
+#include "alloc-util.h"
+#include "btrfs-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "fs-util.h"
+#include "hostname-util.h"
+#include "import-common.h"
+#include "import-util.h"
+#include "machine-image.h"
+#include "mkdir.h"
+#include "ratelimit.h"
+#include "rm-rf.h"
+#include "string-util.h"
+#include "verbs.h"
+#include "parse-util.h"
+
+static bool arg_force = false;
+static bool arg_read_only = false;
+static const char *arg_image_root = "/var/lib/machines";
+
+typedef struct ProgressInfo {
+        RateLimit limit;
+        char *path;
+        uint64_t size;
+        bool started;
+        bool logged_incomplete;
+} ProgressInfo;
+
+static volatile sig_atomic_t cancelled = false;
+
+static void sigterm_sigint(int sig) {
+        cancelled = true;
+}
+
+static void progress_info_free(ProgressInfo *p) {
+        free(p->path);
+}
+
+static void progress_show(ProgressInfo *p) {
+        assert(p);
+
+        /* Show progress only every now and then. */
+        if (!ratelimit_below(&p->limit))
+                return;
+
+        /* Suppress the first message, start with the second one */
+        if (!p->started) {
+                p->started = true;
+                return;
+        }
+
+        /* Mention the list is incomplete before showing first output. */
+        if (!p->logged_incomplete) {
+                log_notice("(Note, file list shown below is incomplete, and is intended as sporadic progress report only.)");
+                p->logged_incomplete = true;
+        }
+
+        if (p->size == 0)
+                log_info("Copying tree, currently at '%s'...", p->path);
+        else {
+                char buffer[FORMAT_BYTES_MAX];
+
+                log_info("Copying tree, currently at '%s' (@%s)...", p->path, format_bytes(buffer, sizeof(buffer), p->size));
+        }
+}
+
+static int progress_path(const char *path, const struct stat *st, void *userdata) {
+        ProgressInfo *p = userdata;
+        int r;
+
+        assert(p);
+
+        if (cancelled)
+                return -EOWNERDEAD;
+
+        r = free_and_strdup(&p->path, path);
+        if (r < 0)
+                return r;
+
+        p->size = 0;
+
+        progress_show(p);
+        return 0;
+}
+
+static int progress_bytes(uint64_t nbytes, void *userdata) {
+        ProgressInfo *p = userdata;
+
+        assert(p);
+        assert(p->size != UINT64_MAX);
+
+        if (cancelled)
+                return -EOWNERDEAD;
+
+        p->size += nbytes;
+
+        progress_show(p);
+        return 0;
+}
+
+static int import_fs(int argc, char *argv[], void *userdata) {
+        _cleanup_(rm_rf_subvolume_and_freep) char *temp_path = NULL;
+        _cleanup_(progress_info_free) ProgressInfo progress = {};
+        const char *path = NULL, *local = NULL, *final_path;
+        _cleanup_close_ int open_fd = -1;
+        struct sigaction old_sigint_sa, old_sigterm_sa;
+        static const struct sigaction sa = {
+                .sa_handler = sigterm_sigint,
+                .sa_flags = SA_RESTART,
+        };
+        int r, fd;
+
+        if (argc >= 2)
+                path = argv[1];
+        if (isempty(path) || streq(path, "-"))
+                path = NULL;
+
+        if (argc >= 3)
+                local = argv[2];
+        else if (path)
+                local = basename(path);
+        if (isempty(local) || streq(local, "-"))
+                local = NULL;
+
+        if (local) {
+                if (!machine_name_is_valid(local)) {
+                        log_error("Local image name '%s' is not valid.", local);
+                        return -EINVAL;
+                }
+
+                if (!arg_force) {
+                        r = image_find(IMAGE_MACHINE, local, NULL);
+                        if (r < 0) {
+                                if (r != -ENOENT)
+                                        return log_error_errno(r, "Failed to check whether image '%s' exists: %m", local);
+                        } else {
+                                log_error("Image '%s' already exists.", local);
+                                return -EEXIST;
+                        }
+                }
+        } else
+                local = "imported";
+
+        if (path) {
+                open_fd = open(path, O_DIRECTORY|O_RDONLY|O_CLOEXEC);
+                if (open_fd < 0)
+                        return log_error_errno(errno, "Failed to open directory to import: %m");
+
+                fd = open_fd;
+
+                log_info("Importing '%s', saving as '%s'.", path, local);
+        } else {
+                _cleanup_free_ char *pretty = NULL;
+
+                fd = STDIN_FILENO;
+
+                (void) fd_get_path(fd, &pretty);
+                log_info("Importing '%s', saving as '%s'.", strempty(pretty), local);
+        }
+
+        final_path = strjoina(arg_image_root, "/", local);
+
+        r = tempfn_random(final_path, NULL, &temp_path);
+        if (r < 0)
+                return log_oom();
+
+        (void) mkdir_parents_label(temp_path, 0700);
+
+        RATELIMIT_INIT(progress.limit, 200*USEC_PER_MSEC, 1);
+
+        /* Hook into SIGINT/SIGTERM, so that we can cancel things then */
+        assert(sigaction(SIGINT, &sa, &old_sigint_sa) >= 0);
+        assert(sigaction(SIGTERM, &sa, &old_sigterm_sa) >= 0);
+
+        r = btrfs_subvol_snapshot_fd_full(
+                        fd,
+                        temp_path,
+                        BTRFS_SNAPSHOT_FALLBACK_COPY|BTRFS_SNAPSHOT_RECURSIVE|BTRFS_SNAPSHOT_FALLBACK_DIRECTORY|BTRFS_SNAPSHOT_QUOTA,
+                        progress_path,
+                        progress_bytes,
+                        &progress);
+        if (r == -EOWNERDEAD) { /* SIGINT + SIGTERM cause this, see signal handler above */
+                log_error("Copy cancelled.");
+                goto finish;
+        }
+        if (r < 0) {
+                log_error_errno(r, "Failed to copy directory: %m");
+                goto finish;
+        }
+
+        (void) import_assign_pool_quota_and_warn(temp_path);
+
+        if (arg_read_only) {
+                r = import_make_read_only(temp_path);
+                if (r < 0) {
+                        log_error_errno(r, "Failed to make directory read-only: %m");
+                        goto finish;
+                }
+        }
+
+        if (arg_force)
+                (void) rm_rf(final_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
+
+        r = rename_noreplace(AT_FDCWD, temp_path, AT_FDCWD, final_path);
+        if (r < 0) {
+                log_error_errno(r, "Failed to move image into place: %m");
+                goto finish;
+        }
+
+        temp_path = mfree(temp_path);
+
+        log_info("Exiting.");
+
+finish:
+        /* Put old signal handlers into place */
+        assert(sigaction(SIGINT, &old_sigint_sa, NULL) >= 0);
+        assert(sigaction(SIGTERM, &old_sigterm_sa, NULL) >= 0);
+
+        return 0;
+}
+
+static int help(int argc, char *argv[], void *userdata) {
+
+        printf("%s [OPTIONS...] {COMMAND} ...\n\n"
+               "Import container images from a file system.\n\n"
+               "  -h --help                   Show this help\n"
+               "     --version                Show package version\n"
+               "     --force                  Force creation of image\n"
+               "     --image-root=PATH        Image root directory\n"
+               "     --read-only              Create a read-only image\n\n"
+               "Commands:\n"
+               "  run DIRECTORY [NAME]             Import a directory\n",
+               program_invocation_short_name);
+
+        return 0;
+}
+
+static int parse_argv(int argc, char *argv[]) {
+
+        enum {
+                ARG_VERSION = 0x100,
+                ARG_FORCE,
+                ARG_IMAGE_ROOT,
+                ARG_READ_ONLY,
+        };
+
+        static const struct option options[] = {
+                { "help",            no_argument,       NULL, 'h'                 },
+                { "version",         no_argument,       NULL, ARG_VERSION         },
+                { "force",           no_argument,       NULL, ARG_FORCE           },
+                { "image-root",      required_argument, NULL, ARG_IMAGE_ROOT      },
+                { "read-only",       no_argument,       NULL, ARG_READ_ONLY       },
+                {}
+        };
+
+        int c;
+
+        assert(argc >= 0);
+        assert(argv);
+
+        while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
+
+                switch (c) {
+
+                case 'h':
+                        return help(0, NULL, NULL);
+
+                case ARG_VERSION:
+                        return version();
+
+                case ARG_FORCE:
+                        arg_force = true;
+                        break;
+
+                case ARG_IMAGE_ROOT:
+                        arg_image_root = optarg;
+                        break;
+
+                case ARG_READ_ONLY:
+                        arg_read_only = true;
+                        break;
+
+                case '?':
+                        return -EINVAL;
+
+                default:
+                        assert_not_reached("Unhandled option");
+                }
+
+        return 1;
+}
+
+static int import_fs_main(int argc, char *argv[]) {
+
+        static const Verb verbs[] = {
+                { "help", VERB_ANY, VERB_ANY, 0, help      },
+                { "run",  2,        3,        0, import_fs },
+                {}
+        };
+
+        return dispatch_verb(argc, argv, verbs, NULL);
+}
+
+int main(int argc, char *argv[]) {
+        int r;
+
+        setlocale(LC_ALL, "");
+        log_parse_environment();
+        log_open();
+
+        r = parse_argv(argc, argv);
+        if (r <= 0)
+                goto finish;
+
+        r = import_fs_main(argc, argv);
+
+finish:
+        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}