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6 .\" This software was developed at the University of Cambridge Computer
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36 .Dt CAP_RIGHTS_LIMIT 2
39 .Nm cap_rights_limit ,
41 .Nd manage capability rights
47 .Fn cap_rights_limit "int fd" "cap_rights_t rights"
49 .Fn cap_rights_get "int fd" "cap_rights_t *rightsp"
51 When a file descriptor is created by a function such as
63 it is assigned all capability rights.
64 Those rights can be reduced (but never expanded) by using the
67 Once capability rights are reduced, operations on the file descriptor will be
68 limited to those permitted by
71 A bitmask of capability rights assigned to a file descriptor can be obtained with
76 The following rights may be specified in a rights mask:
77 .Bl -tag -width CAP_EXTATTR_DELETE
82 Permit checking of an ACL on a file descriptor; there is no cross-reference
86 .Xr acl_delete_fd_np 3 .
100 Note that sockets can also become bound implicitly as a result of
104 and that socket options set with
106 may also affect binding behavior.
110 This right has to be present on the directory descriptor.
116 with a non-NULL destination address.
120 This right has to be present on the directory descriptor.
127 .\" XXXPJD: Doesn't exist anymore.
134 to be used in monitoring the file descriptor for events.
144 will also be required.
145 .It Dv CAP_EXTATTR_DELETE
147 .Xr extattr_delete_fd 2 .
148 .It Dv CAP_EXTATTR_GET
150 .Xr extattr_get_fd 2 .
151 .It Dv CAP_EXTATTR_LIST
153 .Xr extattr_list_fd 2 .
154 .It Dv CAP_EXTATTR_SET
156 .Xr extattr_set_fd 2 .
188 commands require this capability right.
189 Also note that the list of permitted commands can be further limited with the
190 .Xr cap_fcntls_limit 2
212 Permit UFS background-fsck operations on the descriptor.
251 .It Dv CAP_GETPEERNAME
254 .It Dv CAP_GETSOCKNAME
257 .It Dv CAP_GETSOCKOPT
263 Be aware that this system call has enormous scope, including potentially
264 global scope for some objects.
265 The list of permitted ioctl commands can be further limited with the
266 .Xr cap_ioctls_limit 2
268 .\" XXXPJD: Doesn't exist anymore.
273 is also required on file descriptors that will be monitored using
280 This right is required for the destination directory descriptor.
284 not much use (generally) without
287 Permit the file descriptor to be used as a starting directory for calls such as
377 .\" XXXPJD: Not documented.
378 .It Dv CAP_POLL_EVENT
379 .\" XXXPJD: Not documented.
380 .It Dv CAP_POST_EVENT
401 and related system calls.
408 This right is required for the source directory descriptor.
410 Permit operations that seek on the file descriptor, such as
412 but also required for I/O system calls that can read or write at any position
417 .It Dv CAP_SEM_GETVALUE
431 .It Dv CAP_SETSOCKOPT
434 this controls various aspects of socket behavior and may affect binding,
435 connecting, and other behaviors with global scope.
439 closing the socket will also generally shut down any connections on it.
444 Allow configuration of TTY hooks, such as
446 on the file descriptor.
452 This right is only required for
454 on the destination directory descriptor if the destination object already
455 exists and will be removed by the rename.
469 and related system calls.
472 with a non-NULL connection address,
479 flag, but without the
494 argument is not a valid active descriptor.
496 An invalid right has been requested in
498 .It Bq Er ENOTCAPABLE
500 contains requested rights not present in the current rights mask associated
501 with the given file descriptor.
510 argument is not a valid active descriptor.
514 argument points at an invalid address.
524 .Xr cap_fcntls_limit 2 ,
525 .Xr cap_ioctls_limit 2 ,
526 .Xr cap_rights_limit 2 ,
531 .Xr extattr_delete_fd 2 ,
532 .Xr extattr_get_fd 2 ,
533 .Xr extattr_list_fd 2 ,
534 .Xr extattr_set_fd 2 ,
585 .Xr acl_delete_fd_np 3 ,
587 .Xr acl_get_fd_np 3 ,
588 .Xr acl_set_fd_np 3 ,
600 Support for capabilities and capabilities mode was developed as part of the
604 This function was created by
605 .An Pawel Jakub Dawidek Aq pawel@dawidek.net
606 under sponsorship of the FreeBSD Foundation.
608 This man page should list the set of permitted system calls more specifically
609 for each capability right.
611 Capability rights sometimes have unclear indirect impacts, which should be
612 documented, or at least hinted at.