runc/security/capabilities/capabilities.go

36 lines
918 B
Go

package capabilities
import (
"github.com/dotcloud/docker/pkg/libcontainer"
"github.com/syndtr/gocapability/capability"
"os"
)
// DropCapabilities drops capabilities for the current process based
// on the container's configuration.
func DropCapabilities(container *libcontainer.Container) error {
if drop := getCapabilitiesMask(container); len(drop) > 0 {
c, err := capability.NewPid(os.Getpid())
if err != nil {
return err
}
c.Unset(capability.CAPS|capability.BOUNDS, drop...)
if err := c.Apply(capability.CAPS | capability.BOUNDS); err != nil {
return err
}
}
return nil
}
// getCapabilitiesMask returns the specific cap mask values for the libcontainer types
func getCapabilitiesMask(container *libcontainer.Container) []capability.Cap {
drop := []capability.Cap{}
for _, c := range container.CapabilitiesMask {
if !c.Enabled {
drop = append(drop, c.Value)
}
}
return drop
}