func newPortMapper(config *DaemonConfig) (*PortMapper, error) {
// We can always try removing the iptables
if err := iptables.RemoveExistingChain("DOCKER"); err != nil {
return nil, err
}
var chain *iptables.Chain
if config.EnableIptables {
var err error
chain, err = iptables.NewChain("DOCKER", config.BridgeIface)
if err != nil {
return nil, fmt.Errorf("Failed to create DOCKER chain: %s", err)
}
}
mapper := &PortMapper{
tcpMapping: make(map[string]*net.TCPAddr),
tcpProxies: make(map[string]proxy.Proxy),
udpMapping: make(map[string]*net.UDPAddr),
udpProxies: make(map[string]proxy.Proxy),
iptables: chain,
defaultIp: config.DefaultIp,
proxyFactoryFunc: proxy.NewProxy,
}
return mapper, nil
}
func InitDriver(job *engine.Job) engine.Status {
var (
network *net.IPNet
enableIPTables = job.GetenvBool("EnableIptables")
icc = job.GetenvBool("InterContainerCommunication")
ipForward = job.GetenvBool("EnableIpForward")
bridgeIP = job.Getenv("BridgeIP")
)
if defaultIP := job.Getenv("DefaultBindingIP"); defaultIP != "" {
defaultBindingIP = net.ParseIP(defaultIP)
}
bridgeIface = job.Getenv("BridgeIface")
usingDefaultBridge := false
if bridgeIface == "" {
usingDefaultBridge = true
bridgeIface = DefaultNetworkBridge
}
addr, err := networkdriver.GetIfaceAddr(bridgeIface)
if err != nil {
// If we're not using the default bridge, fail without trying to create it
if !usingDefaultBridge {
job.Logf("bridge not found: %s", bridgeIface)
return job.Error(err)
}
// If the iface is not found, try to create it
job.Logf("creating new bridge for %s", bridgeIface)
if err := createBridge(bridgeIP); err != nil {
return job.Error(err)
}
job.Logf("getting iface addr")
addr, err = networkdriver.GetIfaceAddr(bridgeIface)
if err != nil {
return job.Error(err)
}
network = addr.(*net.IPNet)
} else {
network = addr.(*net.IPNet)
// validate that the bridge ip matches the ip specified by BridgeIP
if bridgeIP != "" {
bip, _, err := net.ParseCIDR(bridgeIP)
if err != nil {
return job.Error(err)
}
if !network.IP.Equal(bip) {
return job.Errorf("bridge ip (%s) does not match existing bridge configuration %s", network.IP, bip)
}
}
}
// Configure iptables for link support
if enableIPTables {
if err := setupIPTables(addr, icc); err != nil {
return job.Error(err)
}
}
if ipForward {
// Enable IPv4 forwarding
if err := ioutil.WriteFile("/proc/sys/net/ipv4/ip_forward", []byte{'1', '\n'}, 0644); err != nil {
job.Logf("WARNING: unable to enable IPv4 forwarding: %s\n", err)
}
}
// We can always try removing the iptables
if err := iptables.RemoveExistingChain("DOCKER"); err != nil {
return job.Error(err)
}
if enableIPTables {
chain, err := iptables.NewChain("DOCKER", bridgeIface)
if err != nil {
return job.Error(err)
}
portmapper.SetIptablesChain(chain)
}
bridgeNetwork = network
// https://github.com/dotcloud/docker/issues/2768
job.Eng.Hack_SetGlobalVar("httpapi.bridgeIP", bridgeNetwork.IP)
for name, f := range map[string]engine.Handler{
"allocate_interface": Allocate,
"release_interface": Release,
"allocate_port": AllocatePort,
"link": LinkContainers,
} {
if err := job.Eng.Register(name, f); err != nil {
return job.Error(err)
}
}
return engine.StatusOK
}
func newNetworkManager(config *DaemonConfig) (*NetworkManager, error) {
if config.BridgeIface == DisableNetworkBridge {
manager := &NetworkManager{
disabled: true,
}
return manager, nil
}
var network *net.IPNet
addr, err := getIfaceAddr(config.BridgeIface)
if err != nil {
// If the iface is not found, try to create it
if err := CreateBridgeIface(config); err != nil {
return nil, err
}
addr, err = getIfaceAddr(config.BridgeIface)
if err != nil {
return nil, err
}
network = addr.(*net.IPNet)
} else {
network = addr.(*net.IPNet)
}
// Configure iptables for link support
if config.EnableIptables {
// Enable NAT
natArgs := []string{"POSTROUTING", "-t", "nat", "-s", addr.String(), "!", "-d", addr.String(), "-j", "MASQUERADE"}
if !iptables.Exists(natArgs...) {
if output, err := iptables.Raw(append([]string{"-A"}, natArgs...)...); err != nil {
return nil, fmt.Errorf("Unable to enable network bridge NAT: %s", err)
} else if len(output) != 0 {
return nil, fmt.Errorf("Error iptables postrouting: %s", output)
}
}
args := []string{"FORWARD", "-i", config.BridgeIface, "-o", config.BridgeIface, "-j"}
acceptArgs := append(args, "ACCEPT")
dropArgs := append(args, "DROP")
if !config.InterContainerCommunication {
iptables.Raw(append([]string{"-D"}, acceptArgs...)...)
if !iptables.Exists(dropArgs...) {
utils.Debugf("Disable inter-container communication")
if output, err := iptables.Raw(append([]string{"-I"}, dropArgs...)...); err != nil {
return nil, fmt.Errorf("Unable to prevent intercontainer communication: %s", err)
} else if len(output) != 0 {
return nil, fmt.Errorf("Error disabling intercontainer communication: %s", output)
}
}
} else {
iptables.Raw(append([]string{"-D"}, dropArgs...)...)
if !iptables.Exists(acceptArgs...) {
utils.Debugf("Enable inter-container communication")
if output, err := iptables.Raw(append([]string{"-I"}, acceptArgs...)...); err != nil {
return nil, fmt.Errorf("Unable to allow intercontainer communication: %s", err)
} else if len(output) != 0 {
return nil, fmt.Errorf("Error enabling intercontainer communication: %s", output)
}
}
}
// Accept all non-intercontainer outgoing packets
outgoingArgs := []string{"FORWARD", "-i", config.BridgeIface, "!", "-o", config.BridgeIface, "-j", "ACCEPT"}
if !iptables.Exists(outgoingArgs...) {
if output, err := iptables.Raw(append([]string{"-I"}, outgoingArgs...)...); err != nil {
return nil, fmt.Errorf("Unable to allow outgoing packets: %s", err)
} else if len(output) != 0 {
return nil, fmt.Errorf("Error iptables allow outgoing: %s", output)
}
}
// Accept incoming packets for existing connections
existingArgs := []string{"FORWARD", "-o", config.BridgeIface, "-m", "conntrack", "--ctstate", "RELATED,ESTABLISHED", "-j", "ACCEPT"}
if !iptables.Exists(existingArgs...) {
if output, err := iptables.Raw(append([]string{"-I"}, existingArgs...)...); err != nil {
return nil, fmt.Errorf("Unable to allow incoming packets: %s", err)
} else if len(output) != 0 {
return nil, fmt.Errorf("Error iptables allow incoming: %s", output)
}
}
}
if config.EnableIpForward {
// Enable IPv4 forwarding
if err := ioutil.WriteFile("/proc/sys/net/ipv4/ip_forward", []byte{'1', '\n'}, 0644); err != nil {
log.Printf("WARNING: unable to enable IPv4 forwarding: %s\n", err)
}
}
// We can always try removing the iptables
if err := iptables.RemoveExistingChain("DOCKER"); err != nil {
return nil, err
}
if config.EnableIptables {
chain, err := iptables.NewChain("DOCKER", config.BridgeIface)
if err != nil {
return nil, err
}
portmapper.SetIptablesChain(chain)
}
manager := &NetworkManager{
bridgeIface: config.BridgeIface,
bridgeNetwork: network,
defaultBindingIP: config.DefaultIp,
}
return manager, nil
}