/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2013 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 . ***/ #include #include "strv.h" #include "utf8.h" #include "btrfs-util.h" #include "path-util.h" #include "machine-image.h" static const char image_search_path[] = "/var/lib/machines\0" "/var/lib/container\0" "/usr/local/lib/machines\0" "/usr/lib/machines\0"; Image *image_unref(Image *i) { if (!i) return NULL; free(i->name); free(i->path); free(i); return NULL; } static int image_new( ImageType t, const char *pretty, const char *path, const char *filename, bool read_only, usec_t crtime, usec_t mtime, Image **ret) { _cleanup_(image_unrefp) Image *i = NULL; assert(t >= 0); assert(t < _IMAGE_TYPE_MAX); assert(pretty); assert(filename); assert(ret); i = new0(Image, 1); if (!i) return -ENOMEM; i->type = t; i->read_only = read_only; i->crtime = crtime; i->mtime = mtime; i->name = strdup(pretty); if (!i->name) return -ENOMEM; if (path) i->path = strjoin(path, "/", filename, NULL); else i->path = strdup(filename); if (!i->path) return -ENOMEM; path_kill_slashes(i->path); *ret = i; i = NULL; return 0; } 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/container/, 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)) { if (!ret) return 1; if (!pretty) pretty = filename; /* btrfs subvolumes have inode 256 */ if (st.st_ino == 256) { _cleanup_close_ int fd = -1; struct statfs sfs; fd = openat(dfd, filename, O_CLOEXEC|O_NOCTTY|O_DIRECTORY); if (fd < 0) return -errno; if (fstatfs(fd, &sfs) < 0) return -errno; if (F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC)) { BtrfsSubvolInfo info; /* It's a btrfs subvolume */ r = btrfs_subvol_get_info_fd(fd, &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; return 1; } } /* It's just a normal directory. */ r = image_new(IMAGE_DIRECTORY, pretty, path, filename, read_only, 0, 0, ret); if (r < 0) return r; return 1; } else if (S_ISREG(st.st_mode) && endswith(filename, ".gpt")) { usec_t crtime = 0; /* It's a GPT block device */ if (!ret) return 1; fd_getcrtime_at(dfd, filename, &crtime, 0); if (!pretty) pretty = strndupa(filename, strlen(filename) - 4); r = image_new(IMAGE_GPT, pretty, path, filename, !(st.st_mode & 0222) || read_only, crtime, timespec_load(&st.st_mtim), ret); if (r < 0) return r; return 1; } return 0; } int image_find(const char *name, Image **ret) { const char *path; int r; assert(name); /* There are no images with invalid names */ if (!image_name_is_valid(name)) return 0; NULSTR_FOREACH(path, image_search_path) { _cleanup_closedir_ DIR *d = NULL; d = opendir(path); if (!d) { if (errno == ENOENT) continue; return -errno; } r = image_make(NULL, dirfd(d), path, name, ret); if (r == 0 || r == -ENOENT) { _cleanup_free_ char *gpt = NULL; gpt = strappend(name, ".gpt"); if (!gpt) return -ENOMEM; r = image_make(NULL, dirfd(d), path, gpt, ret); if (r == 0 || r == -ENOENT) continue; } if (r < 0) return r; return 1; } if (streq(name, ".host")) return image_make(".host", AT_FDCWD, NULL, "/", ret); return 0; }; int image_discover(Hashmap *h) { const char *path; int r; assert(h); NULSTR_FOREACH(path, image_search_path) { _cleanup_closedir_ DIR *d = NULL; struct dirent *de; d = opendir(path); if (!d) { if (errno == ENOENT) continue; return -errno; } FOREACH_DIRENT_ALL(de, d, return -errno) { _cleanup_(image_unrefp) Image *image = NULL; if (!image_name_is_valid(de->d_name)) continue; if (hashmap_contains(h, de->d_name)) continue; r = image_make(NULL, dirfd(d), path, de->d_name, &image); if (r == 0 || r == -ENOENT) continue; if (r < 0) return r; r = hashmap_put(h, image->name, image); if (r < 0) return r; image = NULL; } } if (!hashmap_contains(h, ".host")) { _cleanup_(image_unrefp) Image *image = NULL; r = image_make(".host", AT_FDCWD, NULL, "/", &image); if (r < 0) return r; r = hashmap_put(h, image->name, image); if (r < 0) return r; image = NULL; } return 0; } void image_hashmap_free(Hashmap *map) { Image *i; while ((i = hashmap_steal_first(map))) image_unref(i); hashmap_free(map); } static const char* const image_type_table[_IMAGE_TYPE_MAX] = { [IMAGE_DIRECTORY] = "directory", [IMAGE_SUBVOLUME] = "subvolume", [IMAGE_GPT] = "gpt", }; DEFINE_STRING_TABLE_LOOKUP(image_type, ImageType);