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 #define FAN_ENABLE_AUDIT	0x00000040
40 
41 #define FAN_ALL_INIT_FLAGS	(FAN_CLOEXEC | FAN_NONBLOCK | \
42 				 FAN_ALL_CLASS_BITS | FAN_UNLIMITED_QUEUE |\
43 				 FAN_UNLIMITED_MARKS)
44 
45 /* flags used for fanotify_modify_mark() */
46 #define FAN_MARK_ADD		0x00000001
47 #define FAN_MARK_REMOVE		0x00000002
48 #define FAN_MARK_DONT_FOLLOW	0x00000004
49 #define FAN_MARK_ONLYDIR	0x00000008
50 #define FAN_MARK_MOUNT		0x00000010
51 #define FAN_MARK_IGNORED_MASK	0x00000020
52 #define FAN_MARK_IGNORED_SURV_MODIFY	0x00000040
53 #define FAN_MARK_FLUSH		0x00000080
54 
55 #define FAN_ALL_MARK_FLAGS	(FAN_MARK_ADD |\
56 				 FAN_MARK_REMOVE |\
57 				 FAN_MARK_DONT_FOLLOW |\
58 				 FAN_MARK_ONLYDIR |\
59 				 FAN_MARK_MOUNT |\
60 				 FAN_MARK_IGNORED_MASK |\
61 				 FAN_MARK_IGNORED_SURV_MODIFY |\
62 				 FAN_MARK_FLUSH)
63 
64 /*
65  * All of the events - we build the list by hand so that we can add flags in
66  * the future and not break backward compatibility.  Apps will get only the
67  * events that they originally wanted.  Be sure to add new events here!
68  */
69 #define FAN_ALL_EVENTS (FAN_ACCESS |\
70 			FAN_MODIFY |\
71 			FAN_CLOSE |\
72 			FAN_OPEN)
73 
74 /*
75  * All events which require a permission response from userspace
76  */
77 #define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
78 			     FAN_ACCESS_PERM)
79 
80 #define FAN_ALL_OUTGOING_EVENTS	(FAN_ALL_EVENTS |\
81 				 FAN_ALL_PERM_EVENTS |\
82 				 FAN_Q_OVERFLOW)
83 
84 #define FANOTIFY_METADATA_VERSION	3
85 
86 struct fanotify_event_metadata {
87 	__u32 event_len;
88 	__u8 vers;
89 	__u8 reserved;
90 	__u16 metadata_len;
91 	__aligned_u64 mask;
92 	__s32 fd;
93 	__s32 pid;
94 };
95 
96 struct fanotify_response {
97 	__s32 fd;
98 	__u32 response;
99 };
100 
101 /* Legit userspace responses to a _PERM event */
102 #define FAN_ALLOW	0x01
103 #define FAN_DENY	0x02
104 #define FAN_AUDIT	0x10	/* Bit mask to create audit record for result */
105 
106 /* No fd set in event */
107 #define FAN_NOFD	-1
108 
109 /* Helper functions to deal with fanotify_event_metadata buffers */
110 #define FAN_EVENT_METADATA_LEN (sizeof(struct fanotify_event_metadata))
111 
112 #define FAN_EVENT_NEXT(meta, len) ((len) -= (meta)->event_len, \
113 				   (struct fanotify_event_metadata*)(((char *)(meta)) + \
114 				   (meta)->event_len))
115 
116 #define FAN_EVENT_OK(meta, len)	((long)(len) >= (long)FAN_EVENT_METADATA_LEN && \
117 				(long)(meta)->event_len >= (long)FAN_EVENT_METADATA_LEN && \
118 				(long)(meta)->event_len <= (long)(len))
119 
120 #endif /* _UAPI_LINUX_FANOTIFY_H */
121