import: add support for pulling raw tar balls as containers

Ubuntu provides their cloud images optionally as tarball, hence also
support downloading those.

1 files changed, 201 insertions, 0 deletions

diff --git a/src/import/import-util.c b/src/import/import-util.c
new file mode 100644
index 0000000000..24c8ac1d13
--- /dev/null
+++ b/src/import/import-util.c
@@ -0,0 +1,201 @@
+/*-*- 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 "util.h"
+#include "strv.h"
+#include "copy.h"
+#include "btrfs-util.h"
+#include "import-util.h"
+
+#define FILENAME_ESCAPE "/.#\"\'"
+
+bool http_etag_is_valid(const char *etag) {
+        if (!endswith(etag, "\""))
+                return false;
+
+        if (!startswith(etag, "\"") && !startswith(etag, "W/\""))
+                return false;
+
+        return true;
+}
+
+int import_find_old_etags(const char *url, const char *image_root, int dt, const char *prefix, const char *suffix, char ***etags) {
+        _cleanup_free_ char *escaped_url = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
+        _cleanup_strv_free_ char **l = NULL;
+        struct dirent *de;
+        int r;
+
+        assert(url);
+        assert(etags);
+
+        if (!image_root)
+                image_root = "/var/lib/machines";
+
+        escaped_url = xescape(url, FILENAME_ESCAPE);
+        if (!escaped_url)
+                return -ENOMEM;
+
+        d = opendir(image_root);
+        if (!d) {
+                if (errno == ENOENT) {
+                        *etags = NULL;
+                        return 0;
+                }
+
+                return -errno;
+        }
+
+        FOREACH_DIRENT_ALL(de, d, return -errno) {
+                const char *a, *b;
+                char *u;
+
+                if (de->d_type != DT_UNKNOWN &&
+                    de->d_type != dt)
+                        continue;
+
+                if (prefix) {
+                        a = startswith(de->d_name, prefix);
+                        if (!a)
+                                continue;
+                } else
+                        a = de->d_name;
+
+                a = startswith(a, escaped_url);
+                if (!a)
+                        continue;
+
+                a = startswith(a, ".");
+                if (!a)
+                        continue;
+
+                if (suffix) {
+                        b = endswith(de->d_name, suffix);
+                        if (!b)
+                                continue;
+                } else
+                        b = strchr(de->d_name, 0);
+
+                if (a >= b)
+                        continue;
+
+                u = cunescape_length(a, b - a);
+                if (!u)
+                        return -ENOMEM;
+
+                if (!http_etag_is_valid(u)) {
+                        free(u);
+                        continue;
+                }
+
+                r = strv_consume(&l, u);
+                if (r < 0)
+                        return r;
+        }
+
+        *etags = l;
+        l = NULL;
+
+        return 0;
+}
+
+int import_make_local_copy(const char *final, const char *image_root, const char *local, bool force_local) {
+        const char *p;
+        int r;
+
+        assert(final);
+        assert(local);
+
+        if (!image_root)
+                image_root = "/var/lib/machines";
+
+        p = strappenda(image_root, "/", local);
+
+        if (force_local) {
+                (void) btrfs_subvol_remove(p);
+                (void) rm_rf_dangerous(p, false, true, false);
+        }
+
+        r = btrfs_subvol_snapshot(final, p, false, false);
+        if (r == -ENOTTY) {
+                r = copy_tree(final, p, false);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to copy image: %m");
+        } else if (r < 0)
+                return log_error_errno(r, "Failed to create local image: %m");
+
+        log_info("Created new local image '%s'.", local);
+
+        return 0;
+}
+
+int import_make_read_only(const char *path) {
+        int r;
+
+        r = btrfs_subvol_set_read_only(path, true);
+        if (r == -ENOTTY) {
+                struct stat st;
+
+                r = stat(path, &st);
+                if (r < 0)
+                        return log_error_errno(errno, "Failed to stat temporary image: %m");
+
+                if (chmod(path, st.st_mode & 0755) < 0)
+                        return log_error_errno(errno, "Failed to chmod() final image: %m");
+
+                return 0;
+        }
+        if (r < 0)
+                return log_error_errno(r, "Failed to mark final image read-only: %m");
+
+        return 0;
+}
+
+int import_make_path(const char *url, const char *etag, const char *image_root, const char *prefix, const char *suffix, char **ret) {
+        _cleanup_free_ char *escaped_url = NULL;
+        char *path;
+
+        assert(url);
+        assert(ret);
+
+        if (!image_root)
+                image_root = "/var/lib/machines";
+
+        escaped_url = xescape(url, FILENAME_ESCAPE);
+        if (!escaped_url)
+                return -ENOMEM;
+
+        if (etag) {
+                _cleanup_free_ char *escaped_etag = NULL;
+
+                escaped_etag = xescape(etag, FILENAME_ESCAPE);
+                if (!escaped_etag)
+                        return -ENOMEM;
+
+                path = strjoin(image_root, "/", strempty(prefix), escaped_url, ".", escaped_etag, strempty(suffix), NULL);
+        } else
+                path = strjoin(image_root, "/", strempty(prefix), escaped_url, strempty(suffix), NULL);
+        if (!path)
+                return -ENOMEM;
+
+        *ret = path;
+        return 0;
+}