1 #ifndef _LINUX_FANOTIFY_H
2 #define _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 #ifdef __KERNEL__
53 /* not valid from userspace, only kernel internal */
54 #define FAN_MARK_ONDIR		0x00000100
55 #endif
56 
57 #define FAN_ALL_MARK_FLAGS	(FAN_MARK_ADD |\
58 				 FAN_MARK_REMOVE |\
59 				 FAN_MARK_DONT_FOLLOW |\
60 				 FAN_MARK_ONLYDIR |\
61 				 FAN_MARK_MOUNT |\
62 				 FAN_MARK_IGNORED_MASK |\
63 				 FAN_MARK_IGNORED_SURV_MODIFY |\
64 				 FAN_MARK_FLUSH)
65 
66 /*
67  * All of the events - we build the list by hand so that we can add flags in
68  * the future and not break backward compatibility.  Apps will get only the
69  * events that they originally wanted.  Be sure to add new events here!
70  */
71 #define FAN_ALL_EVENTS (FAN_ACCESS |\
72 			FAN_MODIFY |\
73 			FAN_CLOSE |\
74 			FAN_OPEN)
75 
76 /*
77  * All events which require a permission response from userspace
78  */
79 #define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
80 			     FAN_ACCESS_PERM)
81 
82 #define FAN_ALL_OUTGOING_EVENTS	(FAN_ALL_EVENTS |\
83 				 FAN_ALL_PERM_EVENTS |\
84 				 FAN_Q_OVERFLOW)
85 
86 #define FANOTIFY_METADATA_VERSION	3
87 
88 struct fanotify_event_metadata {
89 	__u32 event_len;
90 	__u8 vers;
91 	__u8 reserved;
92 	__u16 metadata_len;
93 	__aligned_u64 mask;
94 	__s32 fd;
95 	__s32 pid;
96 };
97 
98 struct fanotify_response {
99 	__s32 fd;
100 	__u32 response;
101 };
102 
103 /* Legit userspace responses to a _PERM event */
104 #define FAN_ALLOW	0x01
105 #define FAN_DENY	0x02
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 /* _LINUX_FANOTIFY_H */
121