1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _LINUX_FANOTIFY_H
3#define _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_ATTRIB 0x00000004 /* Metadata changed */
11#define FAN_CLOSE_WRITE 0x00000008 /* Writtable file closed */
12#define FAN_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */
13#define FAN_OPEN 0x00000020 /* File was opened */
14#define FAN_MOVED_FROM 0x00000040 /* File was moved from X */
15#define FAN_MOVED_TO 0x00000080 /* File was moved to Y */
16#define FAN_CREATE 0x00000100 /* Subfile was created */
17#define FAN_DELETE 0x00000200 /* Subfile was deleted */
18#define FAN_DELETE_SELF 0x00000400 /* Self was deleted */
19#define FAN_MOVE_SELF 0x00000800 /* Self was moved */
20#define FAN_OPEN_EXEC 0x00001000 /* File was opened for exec */
21
22#define FAN_Q_OVERFLOW 0x00004000 /* Event queued overflowed */
23
24#define FAN_OPEN_PERM 0x00010000 /* File open in perm check */
25#define FAN_ACCESS_PERM 0x00020000 /* File accessed in perm check */
26#define FAN_OPEN_EXEC_PERM 0x00040000 /* File open/exec in perm check */
27
28#define FAN_EVENT_ON_CHILD 0x08000000 /* Interested in child events */
29
30#define FAN_ONDIR 0x40000000 /* Event occurred against dir */
31
32/* helper events */
33#define FAN_CLOSE (FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE) /* close */
34#define FAN_MOVE (FAN_MOVED_FROM | FAN_MOVED_TO) /* moves */
35
36/* flags used for fanotify_init() */
37#define FAN_CLOEXEC 0x00000001
38#define FAN_NONBLOCK 0x00000002
39
40/* These are NOT bitwise flags. Both bits are used together. */
41#define FAN_CLASS_NOTIF 0x00000000
42#define FAN_CLASS_CONTENT 0x00000004
43#define FAN_CLASS_PRE_CONTENT 0x00000008
44
45/* Deprecated - do not use this in programs and do not add new flags here! */
46#define FAN_ALL_CLASS_BITS (FAN_CLASS_NOTIF | FAN_CLASS_CONTENT | \
47 FAN_CLASS_PRE_CONTENT)
48
49#define FAN_UNLIMITED_QUEUE 0x00000010
50#define FAN_UNLIMITED_MARKS 0x00000020
51#define FAN_ENABLE_AUDIT 0x00000040
52
53/* Flags to determine fanotify event format */
54#define FAN_REPORT_TID 0x00000100 /* event->pid is thread id */
55#define FAN_REPORT_FID 0x00000200 /* Report unique file id */
56#define FAN_REPORT_DIR_FID 0x00000400 /* Report unique directory id */
57#define FAN_REPORT_NAME 0x00000800 /* Report events with name */
58
59/* Convenience macro - FAN_REPORT_NAME requires FAN_REPORT_DIR_FID */
60#define FAN_REPORT_DFID_NAME (FAN_REPORT_DIR_FID | FAN_REPORT_NAME)
61
62/* Deprecated - do not use this in programs and do not add new flags here! */
63#define FAN_ALL_INIT_FLAGS (FAN_CLOEXEC | FAN_NONBLOCK | \
64 FAN_ALL_CLASS_BITS | FAN_UNLIMITED_QUEUE |\
65 FAN_UNLIMITED_MARKS)
66
67/* flags used for fanotify_modify_mark() */
68#define FAN_MARK_ADD 0x00000001
69#define FAN_MARK_REMOVE 0x00000002
70#define FAN_MARK_DONT_FOLLOW 0x00000004
71#define FAN_MARK_ONLYDIR 0x00000008
72/* FAN_MARK_MOUNT is 0x00000010 */
73#define FAN_MARK_IGNORED_MASK 0x00000020
74#define FAN_MARK_IGNORED_SURV_MODIFY 0x00000040
75#define FAN_MARK_FLUSH 0x00000080
76/* FAN_MARK_FILESYSTEM is 0x00000100 */
77
78/* These are NOT bitwise flags. Both bits can be used togther. */
79#define FAN_MARK_INODE 0x00000000
80#define FAN_MARK_MOUNT 0x00000010
81#define FAN_MARK_FILESYSTEM 0x00000100
82
83/* Deprecated - do not use this in programs and do not add new flags here! */
84#define FAN_ALL_MARK_FLAGS (FAN_MARK_ADD |\
85 FAN_MARK_REMOVE |\
86 FAN_MARK_DONT_FOLLOW |\
87 FAN_MARK_ONLYDIR |\
88 FAN_MARK_MOUNT |\
89 FAN_MARK_IGNORED_MASK |\
90 FAN_MARK_IGNORED_SURV_MODIFY |\
91 FAN_MARK_FLUSH)
92
93/* Deprecated - do not use this in programs and do not add new flags here! */
94#define FAN_ALL_EVENTS (FAN_ACCESS |\
95 FAN_MODIFY |\
96 FAN_CLOSE |\
97 FAN_OPEN)
98
99/*
100 * All events which require a permission response from userspace
101 */
102/* Deprecated - do not use this in programs and do not add new flags here! */
103#define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
104 FAN_ACCESS_PERM)
105
106/* Deprecated - do not use this in programs and do not add new flags here! */
107#define FAN_ALL_OUTGOING_EVENTS (FAN_ALL_EVENTS |\
108 FAN_ALL_PERM_EVENTS |\
109 FAN_Q_OVERFLOW)
110
111#define FANOTIFY_METADATA_VERSION 3
112
113struct fanotify_event_metadata {
114 __u32 event_len;
115 __u8 vers;
116 __u8 reserved;
117 __u16 metadata_len;
118 __aligned_u64 mask;
119 __s32 fd;
120 __s32 pid;
121};
122
123#define FAN_EVENT_INFO_TYPE_FID 1
124#define FAN_EVENT_INFO_TYPE_DFID_NAME 2
125#define FAN_EVENT_INFO_TYPE_DFID 3
126
127/* Variable length info record following event metadata */
128struct fanotify_event_info_header {
129 __u8 info_type;
130 __u8 pad;
131 __u16 len;
132};
133
134/*
135 * Unique file identifier info record.
136 * This structure is used for records of types FAN_EVENT_INFO_TYPE_FID,
137 * FAN_EVENT_INFO_TYPE_DFID and FAN_EVENT_INFO_TYPE_DFID_NAME.
138 * For FAN_EVENT_INFO_TYPE_DFID_NAME there is additionally a null terminated
139 * name immediately after the file handle.
140 */
141struct fanotify_event_info_fid {
142 struct fanotify_event_info_header hdr;
143 __kernel_fsid_t fsid;
144 /*
145 * Following is an opaque struct file_handle that can be passed as
146 * an argument to open_by_handle_at(2).
147 */
148 unsigned char handle[0];
149};
150
151struct fanotify_response {
152 __s32 fd;
153 __u32 response;
154};
155
156/* Legit userspace responses to a _PERM event */
157#define FAN_ALLOW 0x01
158#define FAN_DENY 0x02
159#define FAN_AUDIT 0x10 /* Bit mask to create audit record for result */
160
161/* No fd set in event */
162#define FAN_NOFD -1
163
164/* Helper functions to deal with fanotify_event_metadata buffers */
165#define FAN_EVENT_METADATA_LEN (sizeof(struct fanotify_event_metadata))
166
167#define FAN_EVENT_NEXT(meta, len) ((len) -= (meta)->event_len, \
168 (struct fanotify_event_metadata*)(((char *)(meta)) + \
169 (meta)->event_len))
170
171#define FAN_EVENT_OK(meta, len) ((long)(len) >= (long)FAN_EVENT_METADATA_LEN && \
172 (long)(meta)->event_len >= (long)FAN_EVENT_METADATA_LEN && \
173 (long)(meta)->event_len <= (long)(len))
174
175#endif /* _LINUX_FANOTIFY_H */
176