// Allocate an external port and map it to the interface
func AllocatePort(job *engine.Job) engine.Status {
var (
err error
ip = defaultBindingIP
id = job.Args[0]
hostIP = job.Getenv("HostIP")
hostPort = job.GetenvInt("HostPort")
containerPort = job.GetenvInt("ContainerPort")
proto = job.Getenv("Proto")
network = currentInterfaces[id]
)
if hostIP != "" {
ip = net.ParseIP(hostIP)
}
// host ip, proto, and host port
hostPort, err = portallocator.RequestPort(ip, proto, hostPort)
if err != nil {
job.Error(err)
return engine.StatusErr
}
var (
container net.Addr
host net.Addr
)
if proto == "tcp" {
host = &net.TCPAddr{IP: ip, Port: hostPort}
container = &net.TCPAddr{IP: network.IP, Port: containerPort}
} else {
host = &net.UDPAddr{IP: ip, Port: hostPort}
container = &net.UDPAddr{IP: network.IP, Port: containerPort}
}
if err := portmapper.Map(container, ip, hostPort); err != nil {
portallocator.ReleasePort(ip, proto, hostPort)
job.Error(err)
return engine.StatusErr
}
network.PortMappings = append(network.PortMappings, host)
out := engine.Env{}
out.Set("HostIP", ip.String())
out.SetInt("HostPort", hostPort)
if _, err := out.WriteTo(job.Stdout); err != nil {
job.Error(err)
return engine.StatusErr
}
return engine.StatusOK
}
// release an interface for a select ip
func Release(job *engine.Job) engine.Status {
var (
id = job.Args[0]
containerInterface = currentInterfaces[id]
ip net.IP
port int
proto string
)
for _, nat := range containerInterface.PortMappings {
if err := portmapper.Unmap(nat); err != nil {
log.Printf("Unable to unmap port %s: %s", nat, err)
}
// this is host mappings
switch a := nat.(type) {
case *net.TCPAddr:
proto = "tcp"
ip = a.IP
port = a.Port
case *net.UDPAddr:
proto = "udp"
ip = a.IP
port = a.Port
}
if err := portallocator.ReleasePort(ip, proto, port); err != nil {
log.Printf("Unable to release port %s", nat)
}
}
if err := ipallocator.ReleaseIP(bridgeNetwork, &containerInterface.IP); err != nil {
log.Printf("Unable to release ip %s\n", err)
}
return engine.StatusOK
}