cap_ioctls_limit(2) [freebsd man page]

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/capsicum.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
     expanded) 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 obtained 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 total number of ioctls commands for the given file
     descriptor can be obtained by passing NULL as the cmds argument and 0 as the maxcmds argument.  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; otherwise the value -1 is returned and the global variable errno is set to
     indicate 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) commands.

     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> under sponsorship of the FreeBSD Foundation.

BSD
								  March 27, 2014							       BSD

Check Out this Related Man Page

CAP_RIGHTS_GET(3)					   BSD Library Functions Manual 					 CAP_RIGHTS_GET(3)

NAME

     cap_rights_get -- obtain capability rights

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <sys/capsicum.h>

     int
     cap_rights_get(int fd, cap_rights_t *rights);

DESCRIPTION

     The cap_rights_get function allows to obtain current capability rights for the given descriptor.  The function will fill the rights argument
     with all capability rights if they were not limited or capability rights configured during the last successful call of cap_rights_limit(2) on
     the given descriptor.

     The rights argument can be inspected using cap_rights_init(3) family of functions.

     The complete list of the capability rights can be found in the rights(4) manual page.

RETURN VALUES

     Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the
     error.

EXAMPLES

     The following example demonstrates how to limit file descriptor capability rights and how to obtain them.

     cap_rights_t setrights, getrights;
     int fd;

     memset(&setrights, 0, sizeof(setrights));
     memset(&getrights, 0, sizeof(getrights));

     fd = open("/tmp/foo", O_RDONLY);
     if (fd < 0)
	     err(1, "open() failed");

     cap_rights_init(&setrights, CAP_FSTAT, CAP_READ);
     if (cap_rights_limit(fd, &setrights) < 0 && errno != ENOSYS)
	     err(1, "cap_rights_limit() failed");

     if (cap_rights_get(fd, &getrights) < 0 && errno != ENOSYS)
	     err(1, "cap_rights_get() failed");

     assert(memcmp(&setrights, &getrights, sizeof(setrights)) == 0);

ERRORS

     cap_rights_get() succeeds unless:

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

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

SEE ALSO

     cap_rights_limit(2), errno(2), open(2), assert(3), cap_rights_init(3), err(3), memcmp(3), memset(3), capsicum(4), rights(4)

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> under sponsorship of the FreeBSD Foundation.

BSD
								  March 27, 2014							       BSD

Linux and UNIX Man Pages

cap_ioctls_limit(2) [freebsd man page]

Check Out this Related Man Page