Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 143 insertions, 0 deletions

diff --git a/src/shared/mount-util.h b/src/shared/mount-util.h
new file mode 100644
index 0000000..ef31104
--- /dev/null
+++ b/src/shared/mount-util.h
@@ -0,0 +1,143 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <mntent.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "dissect-image.h"
+#include "errno-util.h"
+#include "macro.h"
+#include "pidref.h"
+
+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 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_exchange_graceful(int fsmount_fd, const char *dest, bool mount_beneath);
+
+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) {
+        PROTECT_ERRNO;
+        if (p) {
+                (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) {
+        PROTECT_ERRNO;
+        if (p)
+                (void) umount_recursive(p, 0);
+        return mfree(p);
+}
+DEFINE_TRIVIAL_CLEANUP_FUNC(char*, umount_and_free);
+
+int bind_mount_in_namespace(PidRef *target, const char *propagate_path, const char *incoming_path, const char *src, const char *dest, bool read_only, bool make_file_or_directory);
+int mount_image_in_namespace(PidRef *target, const char *propagate_path, const char *incoming_path, const char *src, const char *dest, bool read_only, bool make_file_or_directory, 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 ensure 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,
+        _REMOUNT_IDMAPPING_MAX,
+        _REMOUNT_IDMAPPING_INVALID = -EINVAL,
+} RemountIdmapping;
+
+int make_userns(uid_t uid_shift, uid_t uid_range, uid_t owner, RemountIdmapping idmapping);
+int remount_idmap_fd(char **p, int userns_fd);
+int remount_idmap(char **p, uid_t uid_shift, uid_t uid_range, uid_t 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);