summaryrefslogtreecommitdiffstats
path: root/src/import/import-common.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/import/import-common.c')
-rw-r--r--src/import/import-common.c304
1 files changed, 304 insertions, 0 deletions
diff --git a/src/import/import-common.c b/src/import/import-common.c
new file mode 100644
index 0000000..319aa07
--- /dev/null
+++ b/src/import/import-common.c
@@ -0,0 +1,304 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <sched.h>
+#include <sys/prctl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "btrfs-util.h"
+#include "capability-util.h"
+#include "chattr-util.h"
+#include "dirent-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "fs-util.h"
+#include "hostname-util.h"
+#include "import-common.h"
+#include "os-util.h"
+#include "process-util.h"
+#include "selinux-util.h"
+#include "signal-util.h"
+#include "stat-util.h"
+#include "tmpfile-util.h"
+
+int import_fork_tar_x(const char *path, pid_t *ret) {
+ _cleanup_close_pair_ int pipefd[2] = EBADF_PAIR;
+ bool use_selinux;
+ pid_t pid;
+ int r;
+
+ assert(path);
+ assert(ret);
+
+ if (pipe2(pipefd, O_CLOEXEC) < 0)
+ return log_error_errno(errno, "Failed to create pipe for tar: %m");
+
+ use_selinux = mac_selinux_use();
+
+ r = safe_fork_full("(tar)",
+ (int[]) { pipefd[0], -EBADF, STDERR_FILENO },
+ NULL, 0,
+ FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_DEATHSIG_SIGTERM|FORK_REARRANGE_STDIO|FORK_LOG, &pid);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ const char *cmdline[] = {
+ "tar",
+ "--ignore-zeros",
+ "--numeric-owner",
+ "-C", path,
+ "-pxf",
+ "-",
+ "--xattrs",
+ "--xattrs-include=*",
+ use_selinux ? "--selinux" : "--no-selinux",
+ NULL
+ };
+
+ uint64_t retain =
+ (1ULL << CAP_CHOWN) |
+ (1ULL << CAP_FOWNER) |
+ (1ULL << CAP_FSETID) |
+ (1ULL << CAP_MKNOD) |
+ (1ULL << CAP_SETFCAP) |
+ (1ULL << CAP_DAC_OVERRIDE);
+
+ /* Child */
+
+ if (unshare(CLONE_NEWNET) < 0)
+ log_warning_errno(errno, "Failed to lock tar into network namespace, ignoring: %m");
+
+ r = capability_bounding_set_drop(retain, true);
+ if (r < 0)
+ log_warning_errno(r, "Failed to drop capabilities, ignoring: %m");
+
+ /* Try "gtar" before "tar". We only test things upstream with GNU tar. Some distros appear to
+ * install a different implementation as "tar" (in particular some that do not support the
+ * same command line switches), but then provide "gtar" as alias for the real thing, hence
+ * let's prefer that. (Yes, it's a bad idea they do that, given they don't provide equivalent
+ * command line support, but we are not here to argue, let's just expose the same
+ * behaviour/implementation everywhere.) */
+ execvp("gtar", (char* const*) cmdline);
+ execvp("tar", (char* const*) cmdline);
+
+ log_error_errno(errno, "Failed to execute tar: %m");
+ _exit(EXIT_FAILURE);
+ }
+
+ *ret = pid;
+
+ return TAKE_FD(pipefd[1]);
+}
+
+int import_fork_tar_c(const char *path, pid_t *ret) {
+ _cleanup_close_pair_ int pipefd[2] = EBADF_PAIR;
+ bool use_selinux;
+ pid_t pid;
+ int r;
+
+ assert(path);
+ assert(ret);
+
+ if (pipe2(pipefd, O_CLOEXEC) < 0)
+ return log_error_errno(errno, "Failed to create pipe for tar: %m");
+
+ use_selinux = mac_selinux_use();
+
+ r = safe_fork_full("(tar)",
+ (int[]) { -EBADF, pipefd[1], STDERR_FILENO },
+ NULL, 0,
+ FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_DEATHSIG_SIGTERM|FORK_REARRANGE_STDIO|FORK_LOG, &pid);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ const char *cmdline[] = {
+ "tar",
+ "-C", path,
+ "-c",
+ "--xattrs",
+ "--xattrs-include=*",
+ use_selinux ? "--selinux" : "--no-selinux",
+ ".",
+ NULL
+ };
+
+ uint64_t retain = (1ULL << CAP_DAC_OVERRIDE);
+
+ /* Child */
+
+ if (unshare(CLONE_NEWNET) < 0)
+ log_error_errno(errno, "Failed to lock tar into network namespace, ignoring: %m");
+
+ r = capability_bounding_set_drop(retain, true);
+ if (r < 0)
+ log_error_errno(r, "Failed to drop capabilities, ignoring: %m");
+
+ execvp("gtar", (char* const*) cmdline);
+ execvp("tar", (char* const*) cmdline);
+
+ log_error_errno(errno, "Failed to execute tar: %m");
+ _exit(EXIT_FAILURE);
+ }
+
+ *ret = pid;
+
+ return TAKE_FD(pipefd[0]);
+}
+
+int import_mangle_os_tree(const char *path) {
+ _cleanup_free_ char *child = NULL, *t = NULL, *joined = NULL;
+ _cleanup_closedir_ DIR *d = NULL, *cd = NULL;
+ struct dirent *dent;
+ struct stat st;
+ int r;
+
+ assert(path);
+
+ /* Some tarballs contain a single top-level directory that contains the actual OS directory tree. Try to
+ * recognize this, and move the tree one level up. */
+
+ r = path_is_os_tree(path);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine whether '%s' is an OS tree: %m", path);
+ if (r > 0) {
+ log_debug("Directory tree '%s' is a valid OS tree.", path);
+ return 0;
+ }
+
+ log_debug("Directory tree '%s' is not recognizable as OS tree, checking whether to rearrange it.", path);
+
+ d = opendir(path);
+ if (!d)
+ return log_error_errno(r, "Failed to open directory '%s': %m", path);
+
+ errno = 0;
+ dent = readdir_no_dot(d);
+ if (!dent) {
+ if (errno != 0)
+ return log_error_errno(errno, "Failed to iterate through directory '%s': %m", path);
+
+ log_debug("Directory '%s' is empty, leaving it as it is.", path);
+ return 0;
+ }
+
+ child = strdup(dent->d_name);
+ if (!child)
+ return log_oom();
+
+ errno = 0;
+ dent = readdir_no_dot(d);
+ if (dent) {
+ if (errno != 0)
+ return log_error_errno(errno, "Failed to iterate through directory '%s': %m", path);
+
+ log_debug("Directory '%s' does not look like an OS tree, and has multiple children, leaving as it is.", path);
+ return 0;
+ }
+
+ if (fstatat(dirfd(d), child, &st, AT_SYMLINK_NOFOLLOW) < 0)
+ return log_debug_errno(errno, "Failed to stat file '%s/%s': %m", path, child);
+ r = stat_verify_directory(&st);
+ if (r < 0) {
+ log_debug_errno(r, "Child '%s' of directory '%s' is not a directory, leaving things as they are.", child, path);
+ return 0;
+ }
+
+ joined = path_join(path, child);
+ if (!joined)
+ return log_oom();
+ r = path_is_os_tree(joined);
+ if (r == -ENOTDIR) {
+ log_debug("Directory '%s' does not look like an OS tree, and contains a single regular file only, leaving as it is.", path);
+ return 0;
+ }
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine whether '%s' is an OS tree: %m", joined);
+ if (r == 0) {
+ log_debug("Neither '%s' nor '%s' is a valid OS tree, leaving them as they are.", path, joined);
+ return 0;
+ }
+
+ /* Nice, we have checked now:
+ *
+ * 1. The top-level directory does not qualify as OS tree
+ * 1. The top-level directory only contains one item
+ * 2. That item is a directory
+ * 3. And that directory qualifies as OS tree
+ *
+ * Let's now rearrange things, moving everything in the inner directory one level up */
+
+ cd = xopendirat(dirfd(d), child, O_NOFOLLOW);
+ if (!cd)
+ return log_error_errno(errno, "Can't open directory '%s': %m", joined);
+
+ log_info("Rearranging '%s', moving OS tree one directory up.", joined);
+
+ /* Let's rename the child to an unguessable name so that we can be sure all files contained in it can be
+ * safely moved up and won't collide with the name. */
+ r = tempfn_random(child, NULL, &t);
+ if (r < 0)
+ return log_oom();
+ r = rename_noreplace(dirfd(d), child, dirfd(d), t);
+ if (r < 0)
+ return log_error_errno(r, "Unable to rename '%s' to '%s/%s': %m", joined, path, t);
+
+ FOREACH_DIRENT_ALL(de, cd, return log_error_errno(errno, "Failed to iterate through directory '%s': %m", joined)) {
+ if (dot_or_dot_dot(de->d_name))
+ continue;
+
+ r = rename_noreplace(dirfd(cd), de->d_name, dirfd(d), de->d_name);
+ if (r < 0)
+ return log_error_errno(r, "Unable to move '%s/%s/%s' to '%s/%s': %m", path, t, de->d_name, path, de->d_name);
+ }
+
+ if (unlinkat(dirfd(d), t, AT_REMOVEDIR) < 0)
+ return log_error_errno(errno, "Failed to remove temporary directory '%s/%s': %m", path, t);
+
+ r = futimens(dirfd(d), (struct timespec[2]) { st.st_atim, st.st_mtim });
+ if (r < 0)
+ log_debug_errno(r, "Failed to adjust top-level timestamps '%s', ignoring: %m", path);
+
+ r = fchmod_and_chown(dirfd(d), st.st_mode, st.st_uid, st.st_gid);
+ if (r < 0)
+ return log_error_errno(r, "Failed to adjust top-level directory mode/ownership '%s': %m", path);
+
+ log_info("Successfully rearranged OS tree.");
+
+ return 0;
+}
+
+bool import_validate_local(const char *name, ImportFlags flags) {
+
+ /* By default we insist on a valid hostname for naming images. But optionally we relax that, in which
+ * case it can be any path name */
+
+ if (FLAGS_SET(flags, IMPORT_DIRECT))
+ return path_is_valid(name);
+
+ return hostname_is_valid(name, 0);
+}
+
+static int interrupt_signal_handler(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+ log_notice("Transfer aborted.");
+ sd_event_exit(sd_event_source_get_event(s), EINTR);
+ return 0;
+}
+
+int import_allocate_event_with_signals(sd_event **ret) {
+ _cleanup_(sd_event_unrefp) sd_event *event = NULL;
+ int r;
+
+ assert(ret);
+
+ r = sd_event_default(&event);
+ if (r < 0)
+ return log_error_errno(r, "Failed to allocate event loop: %m");
+
+ assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, SIGINT, -1) >= 0);
+ (void) sd_event_add_signal(event, NULL, SIGTERM, interrupt_signal_handler, NULL);
+ (void) sd_event_add_signal(event, NULL, SIGINT, interrupt_signal_handler, NULL);
+
+ *ret = TAKE_PTR(event);
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-30 15:16:02 +0000