importd: add new bus calls for importing local tar and raw images

This also adds "machinectl import-raw" and "machinectl import-tar" to
wrap these new bus calls.

THe commands basically do for local files that "machinectl pull-raw" and
friends do for remote files.

1 files changed, 374 insertions, 0 deletions

diff --git a/src/import/import-tar.c b/src/import/import-tar.c
new file mode 100644
index 0000000000..d5b6dadddb
--- /dev/null
+++ b/src/import/import-tar.c
@@ -0,0 +1,374 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <linux/fs.h>
+
+#include "sd-daemon.h"
+#include "sd-event.h"
+#include "util.h"
+#include "path-util.h"
+#include "btrfs-util.h"
+#include "copy.h"
+#include "mkdir.h"
+#include "ratelimit.h"
+#include "machine-pool.h"
+#include "qcow2-util.h"
+#include "import-compress.h"
+#include "import-common.h"
+#include "import-tar.h"
+
+struct TarImport {
+        sd_event *event;
+
+        char *image_root;
+
+        TarImportFinished on_finished;
+        void *userdata;
+
+        char *local;
+        bool force_local;
+        bool read_only;
+        bool grow_machine_directory;
+
+        char *temp_path;
+        char *final_path;
+
+        int input_fd;
+        int tar_fd;
+
+        ImportCompress compress;
+
+        uint64_t written_since_last_grow;
+
+        sd_event_source *input_event_source;
+
+        uint8_t buffer[16*1024];
+        size_t buffer_size;
+
+        uint64_t written_compressed;
+        uint64_t written_uncompressed;
+
+        struct stat st;
+
+        pid_t tar_pid;
+
+        unsigned last_percent;
+        RateLimit progress_rate_limit;
+};
+
+TarImport* tar_import_unref(TarImport *i) {
+        if (!i)
+                return NULL;
+
+        sd_event_unref(i->event);
+
+        if (i->tar_pid > 1) {
+                (void) kill_and_sigcont(i->tar_pid, SIGKILL);
+                (void) wait_for_terminate(i->tar_pid, NULL);
+        }
+
+        if (i->temp_path) {
+                (void) btrfs_subvol_remove(i->temp_path);
+                (void) rm_rf_dangerous(i->temp_path, false, true, false);
+                free(i->temp_path);
+        }
+
+        import_compress_free(&i->compress);
+
+        sd_event_source_unref(i->input_event_source);
+
+        safe_close(i->tar_fd);
+
+        free(i->final_path);
+        free(i->image_root);
+        free(i->local);
+        free(i);
+
+        return NULL;
+}
+
+int tar_import_new(
+                TarImport **ret,
+                sd_event *event,
+                const char *image_root,
+                TarImportFinished on_finished,
+                void *userdata) {
+
+        _cleanup_(tar_import_unrefp) TarImport *i = NULL;
+        int r;
+
+        assert(ret);
+
+        i = new0(TarImport, 1);
+        if (!i)
+                return -ENOMEM;
+
+        i->input_fd = i->tar_fd = -1;
+        i->on_finished = on_finished;
+        i->userdata = userdata;
+
+        RATELIMIT_INIT(i->progress_rate_limit, 500 * USEC_PER_MSEC, 1);
+        i->last_percent = (unsigned) -1;
+
+        i->image_root = strdup(image_root ?: "/var/lib/machines");
+        if (!i->image_root)
+                return -ENOMEM;
+
+        i->grow_machine_directory = path_startswith(i->image_root, "/var/lib/machines");
+
+        if (event)
+                i->event = sd_event_ref(event);
+        else {
+                r = sd_event_default(&i->event);
+                if (r < 0)
+                        return r;
+        }
+
+        *ret = i;
+        i = NULL;
+
+        return 0;
+}
+
+static void tar_import_report_progress(TarImport *i) {
+        unsigned percent;
+        assert(i);
+
+        /* We have no size information, unless the source is a regular file */
+        if (!S_ISREG(i->st.st_mode))
+                return;
+
+        if (i->written_compressed >= (uint64_t) i->st.st_size)
+                percent = 100;
+        else
+                percent = (unsigned) ((i->written_compressed * UINT64_C(100)) / (uint64_t) i->st.st_size);
+
+        if (percent == i->last_percent)
+                return;
+
+        if (!ratelimit_test(&i->progress_rate_limit))
+                return;
+
+        sd_notifyf(false, "X_IMPORT_PROGRESS=%u", percent);
+        log_info("Imported %u%%.", percent);
+
+        i->last_percent = percent;
+}
+
+static int tar_import_finish(TarImport *i) {
+        int r;
+
+        assert(i);
+        assert(i->tar_fd >= 0);
+        assert(i->temp_path);
+        assert(i->final_path);
+
+        i->tar_fd = safe_close(i->tar_fd);
+
+        if (i->tar_pid > 0) {
+                r = wait_for_terminate_and_warn("tar", i->tar_pid, true);
+                i->tar_pid = 0;
+                if (r < 0)
+                        return r;
+        }
+
+        if (i->read_only) {
+                r = import_make_read_only(i->temp_path);
+                if (r < 0)
+                        return r;
+        }
+
+        if (i->force_local) {
+                (void) btrfs_subvol_remove(i->final_path);
+                (void) rm_rf_dangerous(i->final_path, false, true, false);
+        }
+
+        if (renameat2(AT_FDCWD, i->temp_path, AT_FDCWD, i->final_path, RENAME_NOREPLACE) < 0)
+                return log_error_errno(errno, "Failed to move image into place: %m");
+
+        free(i->temp_path);
+        i->temp_path = NULL;
+
+        return 0;
+}
+
+static int tar_import_fork_tar(TarImport *i) {
+        int r;
+
+        assert(i);
+
+        assert(!i->final_path);
+        assert(!i->temp_path);
+        assert(i->tar_fd < 0);
+
+        i->final_path = strjoin(i->image_root, "/", i->local, NULL);
+        if (!i->final_path)
+                return log_oom();
+
+        r = tempfn_random(i->final_path, &i->temp_path);
+        if (r < 0)
+                return log_oom();
+
+        (void) mkdir_parents_label(i->temp_path, 0700);
+
+        r = btrfs_subvol_make(i->temp_path);
+        if (r == -ENOTTY) {
+                if (mkdir(i->temp_path, 0755) < 0)
+                        return log_error_errno(errno, "Failed to create directory %s: %m", i->temp_path);
+        } else if (r < 0)
+                return log_error_errno(errno, "Failed to create subvolume %s: %m", i->temp_path);
+
+        i->tar_fd = import_fork_tar(i->temp_path, &i->tar_pid);
+        if (i->tar_fd < 0)
+                return i->tar_fd;
+
+        return 0;
+}
+
+static int tar_import_write(const void *p, size_t sz, void *userdata) {
+        TarImport *i = userdata;
+        int r;
+
+        if (i->grow_machine_directory && i->written_since_last_grow >= GROW_INTERVAL_BYTES) {
+                i->written_since_last_grow = 0;
+                grow_machine_directory();
+        }
+
+        r = loop_write(i->tar_fd, p, sz, false);
+        if (r < 0)
+                return r;
+
+        i->written_uncompressed += sz;
+        i->written_since_last_grow += sz;
+
+        return 0;
+}
+
+static int tar_import_process(TarImport *i) {
+        ssize_t l;
+        int r;
+
+        assert(i);
+        assert(i->buffer_size < sizeof(i->buffer));
+
+        l = read(i->input_fd, i->buffer + i->buffer_size, sizeof(i->buffer) - i->buffer_size);
+        if (l < 0) {
+                r = log_error_errno(errno, "Failed to read input file: %m");
+                goto finish;
+        }
+        if (l == 0) {
+                if (i->compress.type == IMPORT_COMPRESS_UNKNOWN) {
+                        log_error("Premature end of file: %m");
+                        r = -EIO;
+                        goto finish;
+                }
+
+                r = tar_import_finish(i);
+                goto finish;
+        }
+
+        i->buffer_size += l;
+
+        if (i->compress.type == IMPORT_COMPRESS_UNKNOWN) {
+                r = import_uncompress_detect(&i->compress, i->buffer, i->buffer_size);
+                if (r < 0) {
+                        log_error("Failed to detect file compression: %m");
+                        goto finish;
+                }
+                if (r == 0) /* Need more data */
+                        return 0;
+
+                r = tar_import_fork_tar(i);
+                if (r < 0)
+                        goto finish;
+        }
+
+        r = import_uncompress(&i->compress, i->buffer, i->buffer_size, tar_import_write, i);
+        if (r < 0) {
+                log_error_errno(r, "Failed to decode and write: %m");
+                goto finish;
+        }
+
+        i->written_compressed += i->buffer_size;
+        i->buffer_size = 0;
+
+        tar_import_report_progress(i);
+
+        return 0;
+
+finish:
+        if (i->on_finished)
+                i->on_finished(i, r, i->userdata);
+        else
+                sd_event_exit(i->event, r);
+
+        return 0;
+}
+
+static int tar_import_on_input(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+        TarImport *i = userdata;
+
+        return tar_import_process(i);
+}
+
+static int tar_import_on_defer(sd_event_source *s, void *userdata) {
+        TarImport *i = userdata;
+
+        return tar_import_process(i);
+}
+
+int tar_import_start(TarImport *i, int fd, const char *local, bool force_local, bool read_only) {
+        int r;
+
+        assert(i);
+        assert(fd >= 0);
+        assert(local);
+
+        if (!machine_name_is_valid(local))
+                return -EINVAL;
+
+        if (i->input_fd >= 0)
+                return -EBUSY;
+
+        r = free_and_strdup(&i->local, local);
+        if (r < 0)
+                return r;
+        i->force_local = force_local;
+        i->read_only = read_only;
+
+        if (fstat(fd, &i->st) < 0)
+                return -errno;
+
+        r = sd_event_add_io(i->event, &i->input_event_source, fd, EPOLLIN, tar_import_on_input, i);
+        if (r == -EPERM) {
+                /* This fd does not support epoll, for example because it is a regular file. Busy read in that case */
+                r = sd_event_add_defer(i->event, &i->input_event_source, tar_import_on_defer, i);
+                if (r < 0)
+                        return r;
+
+                r = sd_event_source_set_enabled(i->input_event_source, SD_EVENT_ON);
+        }
+        if (r < 0)
+                return r;
+
+        i->input_fd = fd;
+        return r;
+}