CAP_FCNTLS_LIMIT(2) BSD System Calls Manual CAP_FCNTLS_LIMIT(2)NAME
cap_fcntls_limit, cap_fcntls_get -- manage allowed fcntl commands
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/capsicum.h>
int
cap_fcntls_limit(int fd, uint32_t fcntlrights);
int
cap_fcntls_get(int fd, uint32_t *fcntlrightsp);
DESCRIPTION
If a file descriptor is granted the CAP_FCNTL capability right, the list of allowed fcntl(2) commands can be selectively reduced (but never
expanded) with the cap_fcntls_limit() system call.
A bitmask of allowed fcntls commands for a given file descriptor can be obtained with the cap_fcntls_get() system call.
FLAGS
The following flags may be specified in the fcntlrights argument or returned in the fcntlrightsp argument:
CAP_FCNTL_GETFL Permit F_GETFL command.
CAP_FCNTL_SETFL Permit F_SETFL command.
CAP_FCNTL_GETOWN Permit F_GETOWN command.
CAP_FCNTL_SETOWN Permit F_SETOWN command.
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.
ERRORS
cap_fcntls_limit() succeeds unless:
[EBADF] The fd argument is not a valid descriptor.
[EINVAL] An invalid flag has been passed in fcntlrights.
[ENOTCAPABLE] fcntlrights would expand the list of allowed fcntl(2) commands.
cap_fcntls_get() succeeds unless:
[EBADF] The fd argument is not a valid descriptor.
[EFAULT] The fcntlrightsp argument points at an invalid address.
SEE ALSO cap_ioctls_limit(2), cap_rights_limit(2), fcntl(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