src/nspawn/nspawn-mount.h

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2 #pragma once
   3
   4 #include <stdbool.h>
   5
   6 #include "cgroup-util.h"
   7 #include "volatile-util.h"
   8
   9 typedef enum MountSettingsMask {
  10         MOUNT_FATAL              = 1 << 0, /* if set, a mount error is considered fatal */
  11         MOUNT_USE_USERNS         = 1 << 1, /* if set, mounts are patched considering uid/gid shifts in a user namespace */
  12         MOUNT_IN_USERNS          = 1 << 2, /* if set, the mount is executed in the inner child, otherwise in the outer child */
  13         MOUNT_APPLY_APIVFS_RO    = 1 << 3, /* if set, /proc/sys, and /sys will be mounted read-only, otherwise read-write. */
  14         MOUNT_APPLY_APIVFS_NETNS = 1 << 4, /* if set, /proc/sys/net will be mounted read-write.
  15                                                Works only if MOUNT_APPLY_APIVFS_RO is also set. */
  16         MOUNT_APPLY_TMPFS_TMP    = 1 << 5, /* if set, /tmp will be mounted as tmpfs */
  17         MOUNT_ROOT_ONLY          = 1 << 6, /* if set, only root mounts are mounted */
  18         MOUNT_NON_ROOT_ONLY      = 1 << 7, /* if set, only non-root mounts are mounted */
  19         MOUNT_MKDIR              = 1 << 8, /* if set, make directory to mount over first */
  20         MOUNT_TOUCH              = 1 << 9, /* if set, touch file to mount over first */
  21         MOUNT_PREFIX_ROOT        = 1 << 10,/* if set, prefix the source path with the container's root directory */
  22         MOUNT_FOLLOW_SYMLINKS    = 1 << 11,/* if set, we'll follow symlinks for the mount target */
  23 } MountSettingsMask;
  24
  25 typedef enum CustomMountType {
  26         CUSTOM_MOUNT_BIND,
  27         CUSTOM_MOUNT_TMPFS,
  28         CUSTOM_MOUNT_OVERLAY,
  29         CUSTOM_MOUNT_INACCESSIBLE,
  30         CUSTOM_MOUNT_ARBITRARY,
  31         _CUSTOM_MOUNT_TYPE_MAX,
  32         _CUSTOM_MOUNT_TYPE_INVALID = -EINVAL,
  33 } CustomMountType;
  34
  35 typedef struct CustomMount {
  36         CustomMountType type;
  37         bool read_only;
  38         char *source; /* for overlayfs this is the upper directory */
  39         char *destination;
  40         char *options;
  41         char *work_dir;
  42         char **lower;
  43         char *rm_rf_tmpdir;
  44         char *type_argument; /* only for CUSTOM_MOUNT_ARBITRARY */
  45         bool graceful;
  46         bool in_userns;
  47 } CustomMount;
  48
  49 CustomMount* custom_mount_add(CustomMount **l, size_t *n, CustomMountType t);
  50 void custom_mount_free_all(CustomMount *l, size_t n);
  51 int custom_mount_prepare_all(const char *dest, CustomMount *l, size_t n);
  52
  53 int bind_mount_parse(CustomMount **l, size_t *n, const char *s, bool read_only);
  54 int tmpfs_mount_parse(CustomMount **l, size_t *n, const char *s);
  55 int overlay_mount_parse(CustomMount **l, size_t *n, const char *s, bool read_only);
  56 int inaccessible_mount_parse(CustomMount **l, size_t *n, const char *s);
  57
  58 int mount_all(const char *dest, MountSettingsMask mount_settings, uid_t uid_shift, const char *selinux_apifs_context);
  59 int mount_sysfs(const char *dest, MountSettingsMask mount_settings);
  60
  61 int mount_custom(const char *dest, CustomMount *mounts, size_t n, uid_t uid_shift, uid_t uid_range, const char *selinux_apifs_context, MountSettingsMask mount_settings);
  62 bool has_custom_root_mount(const CustomMount *mounts, size_t n);
  63
  64 int setup_volatile_mode(const char *directory, VolatileMode mode, uid_t uid_shift, const char *selinux_apifs_context);
  65
  66 int pivot_root_parse(char **pivot_root_new, char **pivot_root_old, const char *s);
  67 int setup_pivot_root(const char *directory, const char *pivot_root_new, const char *pivot_root_old);
  68
  69 int tmpfs_patch_options(const char *options,uid_t uid_shift, const char *selinux_apifs_context, char **ret);
  70 int pin_fully_visible_fs(void);
  71 int wipe_fully_visible_fs(int mntns_fd);