mmirecki 01d0031487 Tap plugin
This PR adds a plugin to create tap devices.
The plugin adds a tap device to the container.

The plugin has a workaround for a golang netlink library
which does not allow for tap devices with no owner/group
to be created. When no tap owner/group is requested, the
plugin will fall back to using the ip tool for creating
the tap device. A fix to the golang netlink lib is pending.

Signed-off-by: mmirecki <mmirecki@redhat.com>
2023-02-13 17:14:46 +01:00

39 lines
871 B
Go

package selinux
import (
"golang.org/x/sys/unix"
)
// lgetxattr returns a []byte slice containing the value of
// an extended attribute attr set for path.
func lgetxattr(path, attr string) ([]byte, error) {
// Start with a 128 length byte array
dest := make([]byte, 128)
sz, errno := doLgetxattr(path, attr, dest)
for errno == unix.ERANGE {
// Buffer too small, use zero-sized buffer to get the actual size
sz, errno = doLgetxattr(path, attr, []byte{})
if errno != nil {
return nil, errno
}
dest = make([]byte, sz)
sz, errno = doLgetxattr(path, attr, dest)
}
if errno != nil {
return nil, errno
}
return dest[:sz], nil
}
// doLgetxattr is a wrapper that retries on EINTR
func doLgetxattr(path, attr string, dest []byte) (int, error) {
for {
sz, err := unix.Lgetxattr(path, attr, dest)
if err != unix.EINTR {
return sz, err
}
}
}