xref: /linux/include/uapi/linux/fanotify.h (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 #ifndef _UAPI_LINUX_FANOTIFY_H
2 #define _UAPI_LINUX_FANOTIFY_H
3 
4 #include <linux/types.h>
5 
6 /* the following events that user-space can register for */
7 #define FAN_ACCESS		0x00000001	/* File was accessed */
8 #define FAN_MODIFY		0x00000002	/* File was modified */
9 #define FAN_CLOSE_WRITE		0x00000008	/* Writtable file closed */
10 #define FAN_CLOSE_NOWRITE	0x00000010	/* Unwrittable file closed */
11 #define FAN_OPEN		0x00000020	/* File was opened */
12 
13 #define FAN_Q_OVERFLOW		0x00004000	/* Event queued overflowed */
14 
15 #define FAN_OPEN_PERM		0x00010000	/* File open in perm check */
16 #define FAN_ACCESS_PERM		0x00020000	/* File accessed in perm check */
17 
18 #define FAN_ONDIR		0x40000000	/* event occurred against dir */
19 
20 #define FAN_EVENT_ON_CHILD	0x08000000	/* interested in child events */
21 
22 /* helper events */
23 #define FAN_CLOSE		(FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE) /* close */
24 
25 /* flags used for fanotify_init() */
26 #define FAN_CLOEXEC		0x00000001
27 #define FAN_NONBLOCK		0x00000002
28 
29 /* These are NOT bitwise flags.  Both bits are used togther.  */
30 #define FAN_CLASS_NOTIF		0x00000000
31 #define FAN_CLASS_CONTENT	0x00000004
32 #define FAN_CLASS_PRE_CONTENT	0x00000008
33 #define FAN_ALL_CLASS_BITS	(FAN_CLASS_NOTIF | FAN_CLASS_CONTENT | \
34 				 FAN_CLASS_PRE_CONTENT)
35 
36 #define FAN_UNLIMITED_QUEUE	0x00000010
37 #define FAN_UNLIMITED_MARKS	0x00000020
38 
39 #define FAN_ALL_INIT_FLAGS	(FAN_CLOEXEC | FAN_NONBLOCK | \
40 				 FAN_ALL_CLASS_BITS | FAN_UNLIMITED_QUEUE |\
41 				 FAN_UNLIMITED_MARKS)
42 
43 /* flags used for fanotify_modify_mark() */
44 #define FAN_MARK_ADD		0x00000001
45 #define FAN_MARK_REMOVE		0x00000002
46 #define FAN_MARK_DONT_FOLLOW	0x00000004
47 #define FAN_MARK_ONLYDIR	0x00000008
48 #define FAN_MARK_MOUNT		0x00000010
49 #define FAN_MARK_IGNORED_MASK	0x00000020
50 #define FAN_MARK_IGNORED_SURV_MODIFY	0x00000040
51 #define FAN_MARK_FLUSH		0x00000080
52 
53 #define FAN_ALL_MARK_FLAGS	(FAN_MARK_ADD |\
54 				 FAN_MARK_REMOVE |\
55 				 FAN_MARK_DONT_FOLLOW |\
56 				 FAN_MARK_ONLYDIR |\
57 				 FAN_MARK_MOUNT |\
58 				 FAN_MARK_IGNORED_MASK |\
59 				 FAN_MARK_IGNORED_SURV_MODIFY |\
60 				 FAN_MARK_FLUSH)
61 
62 /*
63  * All of the events - we build the list by hand so that we can add flags in
64  * the future and not break backward compatibility.  Apps will get only the
65  * events that they originally wanted.  Be sure to add new events here!
66  */
67 #define FAN_ALL_EVENTS (FAN_ACCESS |\
68 			FAN_MODIFY |\
69 			FAN_CLOSE |\
70 			FAN_OPEN)
71 
72 /*
73  * All events which require a permission response from userspace
74  */
75 #define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
76 			     FAN_ACCESS_PERM)
77 
78 #define FAN_ALL_OUTGOING_EVENTS	(FAN_ALL_EVENTS |\
79 				 FAN_ALL_PERM_EVENTS |\
80 				 FAN_Q_OVERFLOW)
81 
82 #define FANOTIFY_METADATA_VERSION	3
83 
84 struct fanotify_event_metadata {
85 	__u32 event_len;
86 	__u8 vers;
87 	__u8 reserved;
88 	__u16 metadata_len;
89 	__aligned_u64 mask;
90 	__s32 fd;
91 	__s32 pid;
92 };
93 
94 struct fanotify_response {
95 	__s32 fd;
96 	__u32 response;
97 };
98 
99 /* Legit userspace responses to a _PERM event */
100 #define FAN_ALLOW	0x01
101 #define FAN_DENY	0x02
102 /* No fd set in event */
103 #define FAN_NOFD	-1
104 
105 /* Helper functions to deal with fanotify_event_metadata buffers */
106 #define FAN_EVENT_METADATA_LEN (sizeof(struct fanotify_event_metadata))
107 
108 #define FAN_EVENT_NEXT(meta, len) ((len) -= (meta)->event_len, \
109 				   (struct fanotify_event_metadata*)(((char *)(meta)) + \
110 				   (meta)->event_len))
111 
112 #define FAN_EVENT_OK(meta, len)	((long)(len) >= (long)FAN_EVENT_METADATA_LEN && \
113 				(long)(meta)->event_len >= (long)FAN_EVENT_METADATA_LEN && \
114 				(long)(meta)->event_len <= (long)(len))
115 
116 #endif /* _UAPI_LINUX_FANOTIFY_H */
117