xref: /linux/include/uapi/linux/fanotify.h (revision 48dea9a700c8728cc31a1dd44588b97578de86ee)
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_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 
113 struct 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 */
128 struct 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  */
141 struct 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 
151 struct 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 /* _UAPI_LINUX_FANOTIFY_H */
176