static int image_make(
const char *pretty,
int dfd,
const char *path,
const char *filename,
Image **ret) {
struct stat st;
bool read_only;
int r;
assert(filename);
/* We explicitly *do* follow symlinks here, since we want to
* allow symlinking trees into /var/lib/machines/, and treat
* them normally. */
if (fstatat(dfd, filename, &st, 0) < 0)
return -errno;
read_only =
(path && path_startswith(path, "/usr")) ||
(faccessat(dfd, filename, W_OK, AT_EACCESS) < 0 && errno == EROFS);
if (S_ISDIR(st.st_mode)) {
_cleanup_close_ int fd = -1;
unsigned file_attr = 0;
if (!ret)
return 1;
if (!pretty)
pretty = filename;
fd = openat(dfd, filename, O_CLOEXEC|O_NOCTTY|O_DIRECTORY);
if (fd < 0)
return -errno;
/* btrfs subvolumes have inode 256 */
if (st.st_ino == 256) {
r = btrfs_is_filesystem(fd);
if (r < 0)
return r;
if (r) {
BtrfsSubvolInfo info;
/* It's a btrfs subvolume */
r = btrfs_subvol_get_info_fd(fd, 0, &info);
if (r < 0)
return r;
r = image_new(IMAGE_SUBVOLUME,
pretty,
path,
filename,
info.read_only || read_only,
info.otime,
0,
ret);
if (r < 0)
return r;
if (btrfs_quota_scan_ongoing(fd) == 0) {
BtrfsQuotaInfo quota;
r = btrfs_subvol_get_subtree_quota_fd(fd, 0, "a);
if (r >= 0) {
(*ret)->usage = quota.referenced;
(*ret)->usage_exclusive = quota.exclusive;
(*ret)->limit = quota.referenced_max;
(*ret)->limit_exclusive = quota.exclusive_max;
}
}
return 1;
}
}
/* If the IMMUTABLE bit is set, we consider the
* directory read-only. Since the ioctl is not
* supported everywhere we ignore failures. */
(void) read_attr_fd(fd, &file_attr);
/* It's just a normal directory. */
r = image_new(IMAGE_DIRECTORY,
pretty,
path,
filename,
read_only || (file_attr & FS_IMMUTABLE_FL),
0,
0,
ret);
if (r < 0)
return r;
return 1;
} else if (S_ISREG(st.st_mode) && endswith(filename, ".raw")) {
usec_t crtime = 0;
/* It's a RAW disk image */
if (!ret)
return 1;
fd_getcrtime_at(dfd, filename, &crtime, 0);
if (!pretty)
pretty = strndupa(filename, strlen(filename) - 4);
r = image_new(IMAGE_RAW,
pretty,
path,
filename,
!(st.st_mode & 0222) || read_only,
crtime,
timespec_load(&st.st_mtim),
ret);
if (r < 0)
return r;
(*ret)->usage = (*ret)->usage_exclusive = st.st_blocks * 512;
(*ret)->limit = (*ret)->limit_exclusive = st.st_size;
return 1;
}
return 0;
}
static int image_make(
const char *pretty,
int dfd,
const char *path,
const char *filename,
const struct stat *st,
Image **ret) {
_cleanup_free_ char *pretty_buffer = NULL;
struct stat stbuf;
bool read_only;
int r;
assert(dfd >= 0 || dfd == AT_FDCWD);
assert(filename);
/* We explicitly *do* follow symlinks here, since we want to allow symlinking trees, raw files and block
* devices into /var/lib/machines/, and treat them normally.
*
* This function returns -ENOENT if we can't find the image after all, and -EMEDIUMTYPE if it's not a file we
* recognize. */
if (!st) {
if (fstatat(dfd, filename, &stbuf, 0) < 0)
return -errno;
st = &stbuf;
}
read_only =
(path && path_startswith(path, "/usr")) ||
(faccessat(dfd, filename, W_OK, AT_EACCESS) < 0 && errno == EROFS);
if (S_ISDIR(st->st_mode)) {
_cleanup_close_ int fd = -1;
unsigned file_attr = 0;
if (!ret)
return 0;
if (!pretty) {
r = extract_pretty(filename, NULL, &pretty_buffer);
if (r < 0)
return r;
pretty = pretty_buffer;
}
fd = openat(dfd, filename, O_CLOEXEC|O_NOCTTY|O_DIRECTORY);
if (fd < 0)
return -errno;
/* btrfs subvolumes have inode 256 */
if (st->st_ino == 256) {
r = btrfs_is_filesystem(fd);
if (r < 0)
return r;
if (r) {
BtrfsSubvolInfo info;
/* It's a btrfs subvolume */
r = btrfs_subvol_get_info_fd(fd, 0, &info);
if (r < 0)
return r;
r = image_new(IMAGE_SUBVOLUME,
pretty,
path,
filename,
info.read_only || read_only,
info.otime,
0,
ret);
if (r < 0)
return r;
if (btrfs_quota_scan_ongoing(fd) == 0) {
BtrfsQuotaInfo quota;
r = btrfs_subvol_get_subtree_quota_fd(fd, 0, "a);
if (r >= 0) {
(*ret)->usage = quota.referenced;
(*ret)->usage_exclusive = quota.exclusive;
(*ret)->limit = quota.referenced_max;
(*ret)->limit_exclusive = quota.exclusive_max;
}
}
return 0;
}
}
/* If the IMMUTABLE bit is set, we consider the
* directory read-only. Since the ioctl is not
* supported everywhere we ignore failures. */
(void) read_attr_fd(fd, &file_attr);
/* It's just a normal directory. */
r = image_new(IMAGE_DIRECTORY,
pretty,
path,
filename,
read_only || (file_attr & FS_IMMUTABLE_FL),
0,
0,
ret);
if (r < 0)
return r;
return 0;
} else if (S_ISREG(st->st_mode) && endswith(filename, ".raw")) {
usec_t crtime = 0;
/* It's a RAW disk image */
if (!ret)
return 0;
(void) fd_getcrtime_at(dfd, filename, &crtime, 0);
if (!pretty) {
r = extract_pretty(filename, ".raw", &pretty_buffer);
if (r < 0)
return r;
pretty = pretty_buffer;
}
r = image_new(IMAGE_RAW,
pretty,
path,
filename,
!(st->st_mode & 0222) || read_only,
crtime,
timespec_load(&st->st_mtim),
ret);
if (r < 0)
return r;
(*ret)->usage = (*ret)->usage_exclusive = st->st_blocks * 512;
(*ret)->limit = (*ret)->limit_exclusive = st->st_size;
return 0;
} else if (S_ISBLK(st->st_mode)) {
_cleanup_close_ int block_fd = -1;
uint64_t size = UINT64_MAX;
/* A block device */
if (!ret)
return 0;
if (!pretty) {
r = extract_pretty(filename, NULL, &pretty_buffer);
if (r < 0)
return r;
pretty = pretty_buffer;
}
block_fd = openat(dfd, filename, O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_NOCTTY);
if (block_fd < 0)
log_debug_errno(errno, "Failed to open block device %s/%s, ignoring: %m", path, filename);
else {
/* Refresh stat data after opening the node */
if (fstat(block_fd, &stbuf) < 0)
return -errno;
st = &stbuf;
if (!S_ISBLK(st->st_mode)) /* Verify that what we opened is actually what we think it is */
return -ENOTTY;
if (!read_only) {
int state = 0;
if (ioctl(block_fd, BLKROGET, &state) < 0)
log_debug_errno(errno, "Failed to issue BLKROGET on device %s/%s, ignoring: %m", path, filename);
else if (state)
read_only = true;
}
if (ioctl(block_fd, BLKGETSIZE64, &size) < 0)
log_debug_errno(errno, "Failed to issue BLKGETSIZE64 on device %s/%s, ignoring: %m", path, filename);
block_fd = safe_close(block_fd);
}
r = image_new(IMAGE_BLOCK,
pretty,
path,
filename,
!(st->st_mode & 0222) || read_only,
0,
0,
ret);
if (r < 0)
return r;
if (size != 0 && size != UINT64_MAX)
(*ret)->usage = (*ret)->usage_exclusive = (*ret)->limit = (*ret)->limit_exclusive = size;
return 0;
}
return -EMEDIUMTYPE;
}
int tar_export_start(TarExport *e, const char *path, int fd, ImportCompressType compress) {
_cleanup_close_ int sfd = -1;
int r;
assert(e);
assert(path);
assert(fd >= 0);
assert(compress < _IMPORT_COMPRESS_TYPE_MAX);
assert(compress != IMPORT_COMPRESS_UNKNOWN);
if (e->output_fd >= 0)
return -EBUSY;
sfd = open(path, O_DIRECTORY|O_RDONLY|O_NOCTTY|O_CLOEXEC);
if (sfd < 0)
return -errno;
if (fstat(sfd, &e->st) < 0)
return -errno;
r = fd_nonblock(fd, true);
if (r < 0)
return r;
r = free_and_strdup(&e->path, path);
if (r < 0)
return r;
e->quota_referenced = (uint64_t) -1;
if (e->st.st_ino == 256) { /* might be a btrfs subvolume? */
BtrfsQuotaInfo q;
r = btrfs_subvol_get_subtree_quota_fd(sfd, 0, &q);
if (r >= 0)
e->quota_referenced = q.referenced;
e->temp_path = mfree(e->temp_path);
r = tempfn_random(path, NULL, &e->temp_path);
if (r < 0)
return r;
/* Let's try to make a snapshot, if we can, so that the export is atomic */
r = btrfs_subvol_snapshot_fd(sfd, e->temp_path, BTRFS_SNAPSHOT_READ_ONLY|BTRFS_SNAPSHOT_RECURSIVE);
if (r < 0) {
log_debug_errno(r, "Couldn't create snapshot %s of %s, not exporting atomically: %m", e->temp_path, path);
e->temp_path = mfree(e->temp_path);
}
}
r = import_compress_init(&e->compress, compress);
if (r < 0)
return r;
r = sd_event_add_io(e->event, &e->output_event_source, fd, EPOLLOUT, tar_export_on_output, e);
if (r == -EPERM) {
r = sd_event_add_defer(e->event, &e->output_event_source, tar_export_on_defer, e);
if (r < 0)
return r;
r = sd_event_source_set_enabled(e->output_event_source, SD_EVENT_ON);
}
if (r < 0)
return r;
e->tar_fd = import_fork_tar_c(e->temp_path ?: e->path, &e->tar_pid);
if (e->tar_fd < 0) {
e->output_event_source = sd_event_source_unref(e->output_event_source);
return e->tar_fd;
}
e->output_fd = fd;
return r;
}
