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CAP_IOCTLS_LIMIT(2)	    BSD	System Calls Manual	   CAP_IOCTLS_LIMIT(2)

NAME
     cap_ioctls_limit, cap_ioctls_get -- manage	allowed	ioctl commands

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <sys/capability.h>

     int
     cap_ioctls_limit(int fd, const unsigned long *cmds, size_t	ncmds);

     ssize_t
     cap_ioctls_get(int	fd, unsigned long *cmds, size_t	maxcmds);

DESCRIPTION
     If	a file descriptor is granted the CAP_IOCTL capability right, the list
     of	allowed	ioctl(2) commands can be selectively reduced (but never	ex-
     panded) with the cap_ioctls_limit() system	call.  The cmds	argument is an
     array of ioctl(2) commands	and the	ncmds argument specifies the number of
     elements in the array.  There can be up to	256 elements in	the array.

     The list of allowed ioctl commands	for a given file descriptor can	be ob-
     tained with the cap_ioctls_get() system call.  The	cmds argument points
     at	memory that can	hold up	to maxcmds values.  The	function populates the
     provided buffer with up to	maxcmds	elements, but always returns the total
     number of ioctl commands allowed for the given file descriptor.  The to-
     tal number	of ioctls commands for the given file descriptor can be	ob-
     tained by passing NULL as the cmds	argument and 0 as the maxcmds argu-
     ment.  If all ioctl commands are allowed (CAP_IOCTL capability right is
     assigned to the file descriptor and the cap_ioctls_limit()	system call
     was never called for this file descriptor), the cap_ioctls_get() system
     call will return CAP_IOCTLS_ALL and won't modify the buffer pointed to by
     the cmds argument.

RETURN VALUES
     The cap_ioctls_limit() function returns the value 0 if successful;	other-
     wise the value -1 is returned and the global variable errno is set	to in-
     dicate the	error.

     The cap_ioctls_get() function, if successful, returns the total number of
     allowed ioctl commands or the value CAP_IOCTLS_ALL	if all ioctls commands
     are allowed.  On failure the value	-1 is returned and the global variable
     errno is set to indicate the error.

ERRORS
     cap_ioctls_limit()	succeeds unless:

     [EBADF]		The fd argument	is not a valid descriptor.

     [EFAULT]		The cmds argument points at an invalid address.

     [EINVAL]		The ncmds argument is greater than 256.

     [ENOTCAPABLE]	cmds would expand the list of allowed ioctl(2) com-
			mands.

     cap_ioctls_get() succeeds unless:

     [EBADF]		The fd argument	is not a valid descriptor.

     [EFAULT]		The cmds argument points at invalid address.

SEE ALSO
     cap_fcntls_limit(2), cap_rights_limit(2), ioctl(2)

HISTORY
     Support for capabilities and capabilities mode was	developed as part of
     the TrustedBSD Project.

AUTHORS
     This function was created by Pawel	Jakub Dawidek <pawel@dawidek.net> un-
     der sponsorship of	the FreeBSD Foundation.

BSD			      September	20, 2012			   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | HISTORY | AUTHORS

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