/* SPDX-License-Identifier: LGPL-2.1-or-later */ #pragma once #include #include #include #include #include "alloc-util.h" #include "dissect-image.h" #include "errno-util.h" #include "macro.h" #include "pidref.h" typedef struct SubMount { char *path; int mount_fd; } SubMount; void sub_mount_array_free(SubMount *s, size_t n); int get_sub_mounts(const char *prefix, SubMount **ret_mounts, size_t *ret_n_mounts); int repeat_unmount(const char *path, int flags); int umount_recursive_full(const char *target, int flags, char **keep); static inline int umount_recursive(const char *target, int flags) { return umount_recursive_full(target, flags, NULL); } int bind_remount_recursive_with_mountinfo(const char *prefix, unsigned long new_flags, unsigned long flags_mask, char **deny_list, FILE *proc_self_mountinfo); static inline int bind_remount_recursive(const char *prefix, unsigned long new_flags, unsigned long flags_mask, char **deny_list) { return bind_remount_recursive_with_mountinfo(prefix, new_flags, flags_mask, deny_list, NULL); } int bind_remount_one_with_mountinfo(const char *path, unsigned long new_flags, unsigned long flags_mask, FILE *proc_self_mountinfo); int bind_remount_one(const char *path, unsigned long new_flags, unsigned long flags_mask); int mount_switch_root_full(const char *path, unsigned long mount_propagation_flag, bool force_ms_move); static inline int mount_switch_root(const char *path, unsigned long mount_propagation_flag) { return mount_switch_root_full(path, mount_propagation_flag, false); } DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(FILE*, endmntent, NULL); #define _cleanup_endmntent_ _cleanup_(endmntentp) int mount_verbose_full( int error_log_level, const char *what, const char *where, const char *type, unsigned long flags, const char *options, bool follow_symlink); static inline int mount_follow_verbose( int error_log_level, const char *what, const char *where, const char *type, unsigned long flags, const char *options) { return mount_verbose_full(error_log_level, what, where, type, flags, options, true); } static inline int mount_nofollow_verbose( int error_log_level, const char *what, const char *where, const char *type, unsigned long flags, const char *options) { return mount_verbose_full(error_log_level, what, where, type, flags, options, false); } int umount_verbose( int error_log_level, const char *where, int flags); int mount_option_mangle( const char *options, unsigned long mount_flags, unsigned long *ret_mount_flags, char **ret_remaining_options); int mode_to_inaccessible_node(const char *runtime_dir, mode_t mode, char **dest); int mount_flags_to_string(unsigned long flags, char **ret); /* Useful for usage with _cleanup_(), unmounts, removes a directory and frees the pointer */ static inline char* umount_and_rmdir_and_free(char *p) { if (!p) return NULL; PROTECT_ERRNO; (void) umount_recursive(p, 0); (void) rmdir(p); return mfree(p); } DEFINE_TRIVIAL_CLEANUP_FUNC(char*, umount_and_rmdir_and_free); static inline char* umount_and_free(char *p) { if (!p) return NULL; PROTECT_ERRNO; (void) umount_recursive(p, 0); return mfree(p); } DEFINE_TRIVIAL_CLEANUP_FUNC(char*, umount_and_free); char* umount_and_unlink_and_free(char *p); DEFINE_TRIVIAL_CLEANUP_FUNC(char*, umount_and_unlink_and_free); int mount_exchange_graceful(int fsmount_fd, const char *dest, bool mount_beneath); typedef enum MountInNamespaceFlags { MOUNT_IN_NAMESPACE_READ_ONLY = 1 << 0, MOUNT_IN_NAMESPACE_MAKE_FILE_OR_DIRECTORY = 1 << 1, MOUNT_IN_NAMESPACE_IS_IMAGE = 1 << 2, } MountInNamespaceFlags; int bind_mount_in_namespace( const PidRef *target, const char *propagate_path, const char *incoming_path, const char *src, const char *dest, MountInNamespaceFlags flags); int mount_image_in_namespace( const PidRef *target, const char *propagate_path, const char *incoming_path, const char *src, const char *dest, MountInNamespaceFlags flags, const MountOptions *options, const ImagePolicy *image_policy); int make_mount_point(const char *path); int fd_make_mount_point(int fd); typedef enum RemountIdmapping { REMOUNT_IDMAPPING_NONE, /* Include a mapping from UID_MAPPED_ROOT (i.e. UID 2^31-2) on the backing fs to UID 0 on the * uidmapped fs. This is useful to ensure that the host root user can safely add inodes to the * uidmapped fs (which otherwise wouldn't work as the host root user is not defined on the uidmapped * mount and any attempts to create inodes will then be refused with EOVERFLOW). The idea is that * these inodes are quickly re-chown()ed to more suitable UIDs/GIDs. Any code that intends to be able * to add inodes to file systems mapped this way should set this flag, but given it comes with * certain security implications defaults to off, and requires explicit opt-in. */ REMOUNT_IDMAPPING_HOST_ROOT, /* Define a mapping from root user within the container to the owner of the bind mounted directory. * This ensures no root-owned files will be written in a bind-mounted directory owned by a different * user. No other users are mapped. */ REMOUNT_IDMAPPING_HOST_OWNER, /* Define a mapping from bind-target owner within the container to the host owner of the bind mounted * directory. No other users are mapped. */ REMOUNT_IDMAPPING_HOST_OWNER_TO_TARGET_OWNER, _REMOUNT_IDMAPPING_MAX, _REMOUNT_IDMAPPING_INVALID = -EINVAL, } RemountIdmapping; int make_userns(uid_t uid_shift, uid_t uid_range, uid_t host_owner, uid_t dest_owner, RemountIdmapping idmapping); int remount_idmap_fd(char **p, int userns_fd, uint64_t extra_mount_attr_set); int remount_idmap(char **p, uid_t uid_shift, uid_t uid_range, uid_t host_owner, uid_t dest_owner, RemountIdmapping idmapping); int bind_mount_submounts( const char *source, const char *target); /* Creates a mount point (not parents) based on the source path or stat - ie, a file or a directory */ int make_mount_point_inode_from_stat(const struct stat *st, const char *dest, mode_t mode); int make_mount_point_inode_from_path(const char *source, const char *dest, mode_t mode); int trigger_automount_at(int dir_fd, const char *path); unsigned long credentials_fs_mount_flags(bool ro); int mount_credentials_fs(const char *path, size_t size, bool ro); int make_fsmount(int error_log_level, const char *what, const char *type, unsigned long flags, const char *options, int userns_fd); int path_is_network_fs_harder_at(int dir_fd, const char *path); static inline int path_is_network_fs_harder(const char *path) { return path_is_network_fs_harder_at(AT_FDCWD, path); }