include/uapi/linux/fanotify.h

   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      /* Writable file closed */
  12 #define FAN_CLOSE_NOWRITE       0x00000010      /* Unwritable 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 #define FAN_FS_ERROR            0x00008000      /* Filesystem error */
  24
  25 #define FAN_OPEN_PERM           0x00010000      /* File open in perm check */
  26 #define FAN_ACCESS_PERM         0x00020000      /* File accessed in perm check */
  27 #define FAN_OPEN_EXEC_PERM      0x00040000      /* File open/exec in perm check */
  28
  29 #define FAN_EVENT_ON_CHILD      0x08000000      /* Interested in child events */
  30
  31 #define FAN_RENAME              0x10000000      /* File was renamed */
  32
  33 #define FAN_ONDIR               0x40000000      /* Event occurred against dir */
  34
  35 /* helper events */
  36 #define FAN_CLOSE               (FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE) /* close */
  37 #define FAN_MOVE                (FAN_MOVED_FROM | FAN_MOVED_TO) /* moves */
  38
  39 /* flags used for fanotify_init() */
  40 #define FAN_CLOEXEC             0x00000001
  41 #define FAN_NONBLOCK            0x00000002
  42
  43 /* These are NOT bitwise flags.  Both bits are used together.  */
  44 #define FAN_CLASS_NOTIF         0x00000000
  45 #define FAN_CLASS_CONTENT       0x00000004
  46 #define FAN_CLASS_PRE_CONTENT   0x00000008
  47
  48 /* Deprecated - do not use this in programs and do not add new flags here! */
  49 #define FAN_ALL_CLASS_BITS      (FAN_CLASS_NOTIF | FAN_CLASS_CONTENT | \
  50                                  FAN_CLASS_PRE_CONTENT)
  51
  52 #define FAN_UNLIMITED_QUEUE     0x00000010
  53 #define FAN_UNLIMITED_MARKS     0x00000020
  54 #define FAN_ENABLE_AUDIT        0x00000040
  55
  56 /* Flags to determine fanotify event format */
  57 #define FAN_REPORT_PIDFD        0x00000080      /* Report pidfd for event->pid */
  58 #define FAN_REPORT_TID          0x00000100      /* event->pid is thread id */
  59 #define FAN_REPORT_FID          0x00000200      /* Report unique file id */
  60 #define FAN_REPORT_DIR_FID      0x00000400      /* Report unique directory id */
  61 #define FAN_REPORT_NAME         0x00000800      /* Report events with name */
  62 #define FAN_REPORT_TARGET_FID   0x00001000      /* Report dirent target id  */
  63 #define FAN_REPORT_FD_ERROR     0x00002000      /* event->fd can report error */
  64
  65 /* Convenience macro - FAN_REPORT_NAME requires FAN_REPORT_DIR_FID */
  66 #define FAN_REPORT_DFID_NAME    (FAN_REPORT_DIR_FID | FAN_REPORT_NAME)
  67 /* Convenience macro - FAN_REPORT_TARGET_FID requires all other FID flags */
  68 #define FAN_REPORT_DFID_NAME_TARGET (FAN_REPORT_DFID_NAME | \
  69                                      FAN_REPORT_FID | FAN_REPORT_TARGET_FID)
  70
  71 /* Deprecated - do not use this in programs and do not add new flags here! */
  72 #define FAN_ALL_INIT_FLAGS      (FAN_CLOEXEC | FAN_NONBLOCK | \
  73                                  FAN_ALL_CLASS_BITS | FAN_UNLIMITED_QUEUE |\
  74                                  FAN_UNLIMITED_MARKS)
  75
  76 /* flags used for fanotify_modify_mark() */
  77 #define FAN_MARK_ADD            0x00000001
  78 #define FAN_MARK_REMOVE         0x00000002
  79 #define FAN_MARK_DONT_FOLLOW    0x00000004
  80 #define FAN_MARK_ONLYDIR        0x00000008
  81 /* FAN_MARK_MOUNT is            0x00000010 */
  82 #define FAN_MARK_IGNORED_MASK   0x00000020
  83 #define FAN_MARK_IGNORED_SURV_MODIFY    0x00000040
  84 #define FAN_MARK_FLUSH          0x00000080
  85 /* FAN_MARK_FILESYSTEM is       0x00000100 */
  86 #define FAN_MARK_EVICTABLE      0x00000200
  87 /* This bit is mutually exclusive with FAN_MARK_IGNORED_MASK bit */
  88 #define FAN_MARK_IGNORE         0x00000400
  89
  90 /* These are NOT bitwise flags.  Both bits can be used togther.  */
  91 #define FAN_MARK_INODE          0x00000000
  92 #define FAN_MARK_MOUNT          0x00000010
  93 #define FAN_MARK_FILESYSTEM     0x00000100
  94
  95 /*
  96  * Convenience macro - FAN_MARK_IGNORE requires FAN_MARK_IGNORED_SURV_MODIFY
  97  * for non-inode mark types.
  98  */
  99 #define FAN_MARK_IGNORE_SURV    (FAN_MARK_IGNORE | FAN_MARK_IGNORED_SURV_MODIFY)
 100
 101 /* Deprecated - do not use this in programs and do not add new flags here! */
 102 #define FAN_ALL_MARK_FLAGS      (FAN_MARK_ADD |\
 103                                  FAN_MARK_REMOVE |\
 104                                  FAN_MARK_DONT_FOLLOW |\
 105                                  FAN_MARK_ONLYDIR |\
 106                                  FAN_MARK_MOUNT |\
 107                                  FAN_MARK_IGNORED_MASK |\
 108                                  FAN_MARK_IGNORED_SURV_MODIFY |\
 109                                  FAN_MARK_FLUSH)
 110
 111 /* Deprecated - do not use this in programs and do not add new flags here! */
 112 #define FAN_ALL_EVENTS (FAN_ACCESS |\
 113                         FAN_MODIFY |\
 114                         FAN_CLOSE |\
 115                         FAN_OPEN)
 116
 117 /*
 118  * All events which require a permission response from userspace
 119  */
 120 /* Deprecated - do not use this in programs and do not add new flags here! */
 121 #define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
 122                              FAN_ACCESS_PERM)
 123
 124 /* Deprecated - do not use this in programs and do not add new flags here! */
 125 #define FAN_ALL_OUTGOING_EVENTS (FAN_ALL_EVENTS |\
 126                                  FAN_ALL_PERM_EVENTS |\
 127                                  FAN_Q_OVERFLOW)
 128
 129 #define FANOTIFY_METADATA_VERSION       3
 130
 131 struct fanotify_event_metadata {
 132         __u32 event_len;
 133         __u8 vers;
 134         __u8 reserved;
 135         __u16 metadata_len;
 136         __aligned_u64 mask;
 137         __s32 fd;
 138         __s32 pid;
 139 };
 140
 141 #define FAN_EVENT_INFO_TYPE_FID         1
 142 #define FAN_EVENT_INFO_TYPE_DFID_NAME   2
 143 #define FAN_EVENT_INFO_TYPE_DFID        3
 144 #define FAN_EVENT_INFO_TYPE_PIDFD       4
 145 #define FAN_EVENT_INFO_TYPE_ERROR       5
 146
 147 /* Special info types for FAN_RENAME */
 148 #define FAN_EVENT_INFO_TYPE_OLD_DFID_NAME       10
 149 /* Reserved for FAN_EVENT_INFO_TYPE_OLD_DFID    11 */
 150 #define FAN_EVENT_INFO_TYPE_NEW_DFID_NAME       12
 151 /* Reserved for FAN_EVENT_INFO_TYPE_NEW_DFID    13 */
 152
 153 /* Variable length info record following event metadata */
 154 struct fanotify_event_info_header {
 155         __u8 info_type;
 156         __u8 pad;
 157         __u16 len;
 158 };
 159
 160 /*
 161  * Unique file identifier info record.
 162  * This structure is used for records of types FAN_EVENT_INFO_TYPE_FID,
 163  * FAN_EVENT_INFO_TYPE_DFID and FAN_EVENT_INFO_TYPE_DFID_NAME.
 164  * For FAN_EVENT_INFO_TYPE_DFID_NAME there is additionally a null terminated
 165  * name immediately after the file handle.
 166  */
 167 struct fanotify_event_info_fid {
 168         struct fanotify_event_info_header hdr;
 169         __kernel_fsid_t fsid;
 170         /*
 171          * Following is an opaque struct file_handle that can be passed as
 172          * an argument to open_by_handle_at(2).
 173          */
 174         unsigned char handle[];
 175 };
 176
 177 /*
 178  * This structure is used for info records of type FAN_EVENT_INFO_TYPE_PIDFD.
 179  * It holds a pidfd for the pid that was responsible for generating an event.
 180  */
 181 struct fanotify_event_info_pidfd {
 182         struct fanotify_event_info_header hdr;
 183         __s32 pidfd;
 184 };
 185
 186 struct fanotify_event_info_error {
 187         struct fanotify_event_info_header hdr;
 188         __s32 error;
 189         __u32 error_count;
 190 };
 191
 192 /*
 193  * User space may need to record additional information about its decision.
 194  * The extra information type records what kind of information is included.
 195  * The default is none. We also define an extra information buffer whose
 196  * size is determined by the extra information type.
 197  *
 198  * If the information type is Audit Rule, then the information following
 199  * is the rule number that triggered the user space decision that
 200  * requires auditing.
 201  */
 202
 203 #define FAN_RESPONSE_INFO_NONE          0
 204 #define FAN_RESPONSE_INFO_AUDIT_RULE    1
 205
 206 struct fanotify_response {
 207         __s32 fd;
 208         __u32 response;
 209 };
 210
 211 struct fanotify_response_info_header {
 212         __u8 type;
 213         __u8 pad;
 214         __u16 len;
 215 };
 216
 217 struct fanotify_response_info_audit_rule {
 218         struct fanotify_response_info_header hdr;
 219         __u32 rule_number;
 220         __u32 subj_trust;
 221         __u32 obj_trust;
 222 };
 223
 224 /* Legit userspace responses to a _PERM event */
 225 #define FAN_ALLOW       0x01
 226 #define FAN_DENY        0x02
 227 #define FAN_AUDIT       0x10    /* Bitmask to create audit record for result */
 228 #define FAN_INFO        0x20    /* Bitmask to indicate additional information */
 229
 230 /* No fd set in event */
 231 #define FAN_NOFD        -1
 232 #define FAN_NOPIDFD     FAN_NOFD
 233 #define FAN_EPIDFD      -2
 234
 235 /* Helper functions to deal with fanotify_event_metadata buffers */
 236 #define FAN_EVENT_METADATA_LEN (sizeof(struct fanotify_event_metadata))
 237
 238 #define FAN_EVENT_NEXT(meta, len) ((len) -= (meta)->event_len, \
 239                                    (struct fanotify_event_metadata*)(((char *)(meta)) + \
 240                                    (meta)->event_len))
 241
 242 #define FAN_EVENT_OK(meta, len) ((long)(len) >= (long)FAN_EVENT_METADATA_LEN && \
 243                                 (long)(meta)->event_len >= (long)FAN_EVENT_METADATA_LEN && \
 244                                 (long)(meta)->event_len <= (long)(len))
 245
 246 #endif /* _UAPI_LINUX_FANOTIFY_H */