blob: 874d27d2920be4c742460f9c3aae5d621c129627 [file] [log] [blame]
/* 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] = PIPE_EBADF;
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("(tar)", FORK_RESET_SIGNALS|FORK_DEATHSIG|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 */
pipefd[1] = safe_close(pipefd[1]);
r = rearrange_stdio(TAKE_FD(pipefd[0]), -EBADF, STDERR_FILENO);
if (r < 0) {
log_error_errno(r, "Failed to rearrange stdin/stdout: %m");
_exit(EXIT_FAILURE);
}
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] = PIPE_EBADF;
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("(tar)", FORK_RESET_SIGNALS|FORK_DEATHSIG|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 */
pipefd[0] = safe_close(pipefd[0]);
r = rearrange_stdio(-EBADF, TAKE_FD(pipefd[1]), STDERR_FILENO);
if (r < 0) {
log_error_errno(r, "Failed to rearrange stdin/stdout: %m");
_exit(EXIT_FAILURE);
}
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;
}