1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_FANOTIFY_H
3 #define _LINUX_FANOTIFY_H
4 
5 #include <linux/sysctl.h>
6 #include <uapi/linux/fanotify.h>
7 
8 #define FAN_GROUP_FLAG(group, flag) \
9 	((group)->fanotify_data.flags & (flag))
10 
11 /*
12  * Flags allowed to be passed from/to userspace.
13  *
14  * We intentionally do not add new bits to the old FAN_ALL_* constants, because
15  * they are uapi exposed constants. If there are programs out there using
16  * these constant, the programs may break if re-compiled with new uapi headers
17  * and then run on an old kernel.
18  */
19 
20 /* Group classes where permission events are allowed */
21 #define FANOTIFY_PERM_CLASSES	(FAN_CLASS_CONTENT | \
22 				 FAN_CLASS_PRE_CONTENT)
23 
24 #define FANOTIFY_CLASS_BITS	(FAN_CLASS_NOTIF | FANOTIFY_PERM_CLASSES)
25 
26 #define FANOTIFY_FID_BITS	(FAN_REPORT_DFID_NAME_TARGET)
27 
28 #define FANOTIFY_INFO_MODES	(FANOTIFY_FID_BITS | FAN_REPORT_PIDFD)
29 
30 /*
31  * fanotify_init() flags that require CAP_SYS_ADMIN.
32  * We do not allow unprivileged groups to request permission events.
33  * We do not allow unprivileged groups to get other process pid in events.
34  * We do not allow unprivileged groups to use unlimited resources.
35  */
36 #define FANOTIFY_ADMIN_INIT_FLAGS	(FANOTIFY_PERM_CLASSES | \
37 					 FAN_REPORT_TID | \
38 					 FAN_REPORT_PIDFD | \
39 					 FAN_UNLIMITED_QUEUE | \
40 					 FAN_UNLIMITED_MARKS)
41 
42 /*
43  * fanotify_init() flags that are allowed for user without CAP_SYS_ADMIN.
44  * FAN_CLASS_NOTIF is the only class we allow for unprivileged group.
45  * We do not allow unprivileged groups to get file descriptors in events,
46  * so one of the flags for reporting file handles is required.
47  */
48 #define FANOTIFY_USER_INIT_FLAGS	(FAN_CLASS_NOTIF | \
49 					 FANOTIFY_FID_BITS | \
50 					 FAN_CLOEXEC | FAN_NONBLOCK)
51 
52 #define FANOTIFY_INIT_FLAGS	(FANOTIFY_ADMIN_INIT_FLAGS | \
53 				 FANOTIFY_USER_INIT_FLAGS)
54 
55 /* Internal group flags */
56 #define FANOTIFY_UNPRIV		0x80000000
57 #define FANOTIFY_INTERNAL_GROUP_FLAGS	(FANOTIFY_UNPRIV)
58 
59 #define FANOTIFY_MARK_TYPE_BITS	(FAN_MARK_INODE | FAN_MARK_MOUNT | \
60 				 FAN_MARK_FILESYSTEM)
61 
62 #define FANOTIFY_MARK_CMD_BITS	(FAN_MARK_ADD | FAN_MARK_REMOVE | \
63 				 FAN_MARK_FLUSH)
64 
65 #define FANOTIFY_MARK_IGNORE_BITS (FAN_MARK_IGNORED_MASK | \
66 				   FAN_MARK_IGNORE)
67 
68 #define FANOTIFY_MARK_FLAGS	(FANOTIFY_MARK_TYPE_BITS | \
69 				 FANOTIFY_MARK_CMD_BITS | \
70 				 FANOTIFY_MARK_IGNORE_BITS | \
71 				 FAN_MARK_DONT_FOLLOW | \
72 				 FAN_MARK_ONLYDIR | \
73 				 FAN_MARK_IGNORED_SURV_MODIFY | \
74 				 FAN_MARK_EVICTABLE)
75 
76 /*
77  * Events that can be reported with data type FSNOTIFY_EVENT_PATH.
78  * Note that FAN_MODIFY can also be reported with data type
79  * FSNOTIFY_EVENT_INODE.
80  */
81 #define FANOTIFY_PATH_EVENTS	(FAN_ACCESS | FAN_MODIFY | \
82 				 FAN_CLOSE | FAN_OPEN | FAN_OPEN_EXEC)
83 
84 /*
85  * Directory entry modification events - reported only to directory
86  * where entry is modified and not to a watching parent.
87  */
88 #define FANOTIFY_DIRENT_EVENTS	(FAN_MOVE | FAN_CREATE | FAN_DELETE | \
89 				 FAN_RENAME)
90 
91 /* Events that can be reported with event->fd */
92 #define FANOTIFY_FD_EVENTS (FANOTIFY_PATH_EVENTS | FANOTIFY_PERM_EVENTS)
93 
94 /* Events that can only be reported with data type FSNOTIFY_EVENT_INODE */
95 #define FANOTIFY_INODE_EVENTS	(FANOTIFY_DIRENT_EVENTS | \
96 				 FAN_ATTRIB | FAN_MOVE_SELF | FAN_DELETE_SELF)
97 
98 /* Events that can only be reported with data type FSNOTIFY_EVENT_ERROR */
99 #define FANOTIFY_ERROR_EVENTS	(FAN_FS_ERROR)
100 
101 /* Events that user can request to be notified on */
102 #define FANOTIFY_EVENTS		(FANOTIFY_PATH_EVENTS | \
103 				 FANOTIFY_INODE_EVENTS | \
104 				 FANOTIFY_ERROR_EVENTS)
105 
106 /* Events that require a permission response from user */
107 #define FANOTIFY_PERM_EVENTS	(FAN_OPEN_PERM | FAN_ACCESS_PERM | \
108 				 FAN_OPEN_EXEC_PERM)
109 
110 /* Extra flags that may be reported with event or control handling of events */
111 #define FANOTIFY_EVENT_FLAGS	(FAN_EVENT_ON_CHILD | FAN_ONDIR)
112 
113 /* Events that may be reported to user */
114 #define FANOTIFY_OUTGOING_EVENTS	(FANOTIFY_EVENTS | \
115 					 FANOTIFY_PERM_EVENTS | \
116 					 FAN_Q_OVERFLOW | FAN_ONDIR)
117 
118 /* Events and flags relevant only for directories */
119 #define FANOTIFY_DIRONLY_EVENT_BITS	(FANOTIFY_DIRENT_EVENTS | \
120 					 FAN_EVENT_ON_CHILD | FAN_ONDIR)
121 
122 #define ALL_FANOTIFY_EVENT_BITS		(FANOTIFY_OUTGOING_EVENTS | \
123 					 FANOTIFY_EVENT_FLAGS)
124 
125 /* These masks check for invalid bits in permission responses. */
126 #define FANOTIFY_RESPONSE_ACCESS (FAN_ALLOW | FAN_DENY)
127 #define FANOTIFY_RESPONSE_FLAGS (FAN_AUDIT | FAN_INFO)
128 #define FANOTIFY_RESPONSE_VALID_MASK (FANOTIFY_RESPONSE_ACCESS | FANOTIFY_RESPONSE_FLAGS)
129 
130 /* Do not use these old uapi constants internally */
131 #undef FAN_ALL_CLASS_BITS
132 #undef FAN_ALL_INIT_FLAGS
133 #undef FAN_ALL_MARK_FLAGS
134 #undef FAN_ALL_EVENTS
135 #undef FAN_ALL_PERM_EVENTS
136 #undef FAN_ALL_OUTGOING_EVENTS
137 
138 #endif /* _LINUX_FANOTIFY_H */
139