include/uapi/linux/fanotify.h

   1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
   2 #ifndef _UAPI_LINUX_FANOTIFY_H
   3 #define _UAPI_LINUX_FANOTIFY_H
   4
   5 #include <linux/types.h>
   6
   7 /* the following events that user-space can register for */
   8 #define FAN_ACCESS              0x00000001      /* File was accessed */
   9 #define FAN_MODIFY              0x00000002      /* File was modified */
  10 #define FAN_CLOSE_WRITE         0x00000008      /* Writtable file closed */
  11 #define FAN_CLOSE_NOWRITE       0x00000010      /* Unwrittable file closed */
  12 #define FAN_OPEN                0x00000020      /* File was opened */
  13
  14 #define FAN_Q_OVERFLOW          0x00004000      /* Event queued overflowed */
  15
  16 #define FAN_OPEN_PERM           0x00010000      /* File open in perm check */
  17 #define FAN_ACCESS_PERM         0x00020000      /* File accessed in perm check */
  18
  19 #define FAN_ONDIR               0x40000000      /* event occurred against dir */
  20
  21 #define FAN_EVENT_ON_CHILD      0x08000000      /* interested in child events */
  22
  23 /* helper events */
  24 #define FAN_CLOSE               (FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE) /* close */
  25
  26 /* flags used for fanotify_init() */
  27 #define FAN_CLOEXEC             0x00000001
  28 #define FAN_NONBLOCK            0x00000002
  29
  30 /* These are NOT bitwise flags.  Both bits are used togther.  */
  31 #define FAN_CLASS_NOTIF         0x00000000
  32 #define FAN_CLASS_CONTENT       0x00000004
  33 #define FAN_CLASS_PRE_CONTENT   0x00000008
  34 #define FAN_ALL_CLASS_BITS      (FAN_CLASS_NOTIF | FAN_CLASS_CONTENT | \
  35                                  FAN_CLASS_PRE_CONTENT)
  36
  37 #define FAN_UNLIMITED_QUEUE     0x00000010
  38 #define FAN_UNLIMITED_MARKS     0x00000020
  39
  40 #define FAN_ALL_INIT_FLAGS      (FAN_CLOEXEC | FAN_NONBLOCK | \
  41                                  FAN_ALL_CLASS_BITS | FAN_UNLIMITED_QUEUE |\
  42                                  FAN_UNLIMITED_MARKS)
  43
  44 /* flags used for fanotify_modify_mark() */
  45 #define FAN_MARK_ADD            0x00000001
  46 #define FAN_MARK_REMOVE         0x00000002
  47 #define FAN_MARK_DONT_FOLLOW    0x00000004
  48 #define FAN_MARK_ONLYDIR        0x00000008
  49 #define FAN_MARK_MOUNT          0x00000010
  50 #define FAN_MARK_IGNORED_MASK   0x00000020
  51 #define FAN_MARK_IGNORED_SURV_MODIFY    0x00000040
  52 #define FAN_MARK_FLUSH          0x00000080
  53
  54 #define FAN_ALL_MARK_FLAGS      (FAN_MARK_ADD |\
  55                                  FAN_MARK_REMOVE |\
  56                                  FAN_MARK_DONT_FOLLOW |\
  57                                  FAN_MARK_ONLYDIR |\
  58                                  FAN_MARK_MOUNT |\
  59                                  FAN_MARK_IGNORED_MASK |\
  60                                  FAN_MARK_IGNORED_SURV_MODIFY |\
  61                                  FAN_MARK_FLUSH)
  62
  63 /*
  64  * All of the events - we build the list by hand so that we can add flags in
  65  * the future and not break backward compatibility.  Apps will get only the
  66  * events that they originally wanted.  Be sure to add new events here!
  67  */
  68 #define FAN_ALL_EVENTS (FAN_ACCESS |\
  69                         FAN_MODIFY |\
  70                         FAN_CLOSE |\
  71                         FAN_OPEN)
  72
  73 /*
  74  * All events which require a permission response from userspace
  75  */
  76 #define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
  77                              FAN_ACCESS_PERM)
  78
  79 #define FAN_ALL_OUTGOING_EVENTS (FAN_ALL_EVENTS |\
  80                                  FAN_ALL_PERM_EVENTS |\
  81                                  FAN_Q_OVERFLOW)
  82
  83 #define FANOTIFY_METADATA_VERSION       3
  84
  85 struct fanotify_event_metadata {
  86         __u32 event_len;
  87         __u8 vers;
  88         __u8 reserved;
  89         __u16 metadata_len;
  90         __aligned_u64 mask;
  91         __s32 fd;
  92         __s32 pid;
  93 };
  94
  95 struct fanotify_response {
  96         __s32 fd;
  97         __u32 response;
  98 };
  99
 100 /* Legit userspace responses to a _PERM event */
 101 #define FAN_ALLOW       0x01
 102 #define FAN_DENY        0x02
 103 /* No fd set in event */
 104 #define FAN_NOFD        -1
 105
 106 /* Helper functions to deal with fanotify_event_metadata buffers */
 107 #define FAN_EVENT_METADATA_LEN (sizeof(struct fanotify_event_metadata))
 108
 109 #define FAN_EVENT_NEXT(meta, len) ((len) -= (meta)->event_len, \
 110                                    (struct fanotify_event_metadata*)(((char *)(meta)) + \
 111                                    (meta)->event_len))
 112
 113 #define FAN_EVENT_OK(meta, len) ((long)(len) >= (long)FAN_EVENT_METADATA_LEN && \
 114                                 (long)(meta)->event_len >= (long)FAN_EVENT_METADATA_LEN && \
 115                                 (long)(meta)->event_len <= (long)(len))
 116
 117 #endif /* _UAPI_LINUX_FANOTIFY_H */