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
The cap_fcntls_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.
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
HISTORY
The cap_fcntls_get() and cap_fcntls_limit() system calls first appeared in FreeBSD 8.3. Support for capabilities and capabilities mode was developed as part of the TrustedBSD Project.
AUTHORS
This function was created by Pawel Jakub Dawidek ⟨[email protected]⟩ under sponsorship of the FreeBSD Foundation.