Files
moby/libnetwork/drivers/bridge/bridge_linux.go
Rob Murray cdea750966 Tell RootlessKit about port mappings when --userland-proxy=false
The daemon was modified to tell RootlessKit about host port
mappings directly, rather than by running rootlesskit-docker-proxy
to make those updates.

DNAT rules created in rootless mode referred to the host IP address,
rather than the address seen as host address in the rootless network
namespace.

With these changes, port mappings work in rootless mode when
--userland-proxy=false - so, don't gate the RootlessKit API calls
on starting docker-proxy.

Signed-off-by: Rob Murray <rob.murray@docker.com>
2024-08-05 14:04:05 +01:00

1658 lines
45 KiB
Go

package bridge
import (
"context"
"fmt"
"net"
"net/netip"
"os"
"os/exec"
"strconv"
"sync"
"github.com/containerd/log"
"github.com/docker/docker/errdefs"
"github.com/docker/docker/libnetwork/datastore"
"github.com/docker/docker/libnetwork/driverapi"
"github.com/docker/docker/libnetwork/drivers/bridge/internal/rlkclient"
"github.com/docker/docker/libnetwork/internal/netiputil"
"github.com/docker/docker/libnetwork/iptables"
"github.com/docker/docker/libnetwork/netlabel"
"github.com/docker/docker/libnetwork/netutils"
"github.com/docker/docker/libnetwork/ns"
"github.com/docker/docker/libnetwork/options"
"github.com/docker/docker/libnetwork/scope"
"github.com/docker/docker/libnetwork/types"
"github.com/pkg/errors"
"github.com/vishvananda/netlink"
"go.opentelemetry.io/otel"
"go.opentelemetry.io/otel/attribute"
"go.opentelemetry.io/otel/trace"
)
const (
NetworkType = "bridge"
vethPrefix = "veth"
vethLen = len(vethPrefix) + 7
defaultContainerVethPrefix = "eth"
maxAllocatePortAttempts = 10
)
const (
// DefaultGatewayV4AuxKey represents the default-gateway configured by the user
DefaultGatewayV4AuxKey = "DefaultGatewayIPv4"
// DefaultGatewayV6AuxKey represents the ipv6 default-gateway configured by the user
DefaultGatewayV6AuxKey = "DefaultGatewayIPv6"
)
type (
iptableCleanFunc func() error
iptablesCleanFuncs []iptableCleanFunc
)
// configuration info for the "bridge" driver.
type configuration struct {
EnableIPForwarding bool
EnableIPTables bool
EnableIP6Tables bool
EnableUserlandProxy bool
UserlandProxyPath string
Rootless bool
}
// networkConfiguration for network specific configuration
type networkConfiguration struct {
ID string
BridgeName string
EnableIPv6 bool
EnableIPMasquerade bool
GwModeIPv4 gwMode
GwModeIPv6 gwMode
EnableICC bool
InhibitIPv4 bool
Mtu int
DefaultBindingIP net.IP
DefaultBridge bool
HostIPv4 net.IP
HostIPv6 net.IP
ContainerIfacePrefix string
// Internal fields set after ipam data parsing
AddressIPv4 *net.IPNet
AddressIPv6 *net.IPNet
DefaultGatewayIPv4 net.IP
DefaultGatewayIPv6 net.IP
dbIndex uint64
dbExists bool
Internal bool
BridgeIfaceCreator ifaceCreator
}
// ifaceCreator represents how the bridge interface was created
type ifaceCreator int8
const (
ifaceCreatorUnknown ifaceCreator = iota
ifaceCreatedByLibnetwork
ifaceCreatedByUser
)
// containerConfiguration represents the user specified configuration for a container
type containerConfiguration struct {
ParentEndpoints []string
ChildEndpoints []string
}
// connectivityConfiguration represents the user specified configuration regarding the external connectivity
type connectivityConfiguration struct {
PortBindings []types.PortBinding
ExposedPorts []types.TransportPort
}
type bridgeEndpoint struct {
id string
nid string
srcName string
addr *net.IPNet
addrv6 *net.IPNet
macAddress net.HardwareAddr
containerConfig *containerConfiguration
extConnConfig *connectivityConfiguration
portMapping []portBinding // Operational port bindings
dbIndex uint64
dbExists bool
}
type bridgeNetwork struct {
id string
bridge *bridgeInterface // The bridge's L3 interface
config *networkConfiguration
endpoints map[string]*bridgeEndpoint // key: endpoint id
driver *driver // The network's driver
iptCleanFuncs iptablesCleanFuncs
sync.Mutex
}
type portDriverClient interface {
ChildHostIP(hostIP netip.Addr) netip.Addr
AddPort(ctx context.Context, proto string, hostIP, childIP netip.Addr, hostPort int) (func() error, error)
}
// Allow unit tests to supply a dummy RootlessKit port driver client.
var newPortDriverClient = func(ctx context.Context) (portDriverClient, error) {
return rlkclient.NewPortDriverClient(ctx)
}
type driver struct {
config configuration
natChain *iptables.ChainInfo
filterChain *iptables.ChainInfo
isolationChain1 *iptables.ChainInfo
isolationChain2 *iptables.ChainInfo
natChainV6 *iptables.ChainInfo
filterChainV6 *iptables.ChainInfo
isolationChain1V6 *iptables.ChainInfo
isolationChain2V6 *iptables.ChainInfo
networks map[string]*bridgeNetwork
store *datastore.Store
nlh *netlink.Handle
portDriverClient portDriverClient
configNetwork sync.Mutex
sync.Mutex
}
type gwMode string
const (
gwModeDefault gwMode = ""
gwModeNAT gwMode = "nat"
gwModeRouted gwMode = "routed"
)
// New constructs a new bridge driver
func newDriver() *driver {
return &driver{
networks: map[string]*bridgeNetwork{},
}
}
// Register registers a new instance of bridge driver.
func Register(r driverapi.Registerer, config map[string]interface{}) error {
d := newDriver()
if err := d.configure(config); err != nil {
return err
}
return r.RegisterDriver(NetworkType, d, driverapi.Capability{
DataScope: scope.Local,
ConnectivityScope: scope.Local,
})
}
// The behaviour of previous implementations of bridge subnet prefix assignment
// is preserved here...
//
// The LL prefix, 'fe80::/64' can be used as an IPAM pool. Linux always assigns
// link-local addresses with this prefix. But, pool-assigned addresses are very
// unlikely to conflict.
//
// Don't allow a nonstandard LL subnet to overlap with 'fe80::/64'. For example,
// if the config asked for subnet prefix 'fe80::/80', the bridge and its
// containers would each end up with two LL addresses, Linux's '/64' and one from
// the IPAM pool claiming '/80'. Although the specified prefix length must not
// affect the host's determination of whether the address is on-link and to be
// added to the interface's Prefix List (RFC-5942), differing prefix lengths
// would be confusing and have been disallowed by earlier implementations of
// bridge address assignment.
func validateIPv6Subnet(addr netip.Prefix) error {
if !addr.Addr().Is6() || addr.Addr().Is4In6() {
return fmt.Errorf("'%s' is not a valid IPv6 subnet", addr)
}
if addr.Addr().IsMulticast() {
return fmt.Errorf("multicast subnet '%s' is not allowed", addr)
}
if addr.Masked() != linkLocalPrefix && linkLocalPrefix.Overlaps(addr) {
return fmt.Errorf("'%s' clashes with the Link-Local prefix 'fe80::/64'", addr)
}
return nil
}
// ValidateFixedCIDRV6 checks that val is an IPv6 address and prefix length that
// does not overlap with the link local subnet prefix 'fe80::/64'.
func ValidateFixedCIDRV6(val string) error {
if val == "" {
return nil
}
prefix, err := netip.ParsePrefix(val)
if err == nil {
err = validateIPv6Subnet(prefix)
}
return errdefs.InvalidParameter(errors.Wrap(err, "invalid fixed-cidr-v6"))
}
// Validate performs a static validation on the network configuration parameters.
// Whatever can be assessed a priori before attempting any programming.
func (c *networkConfiguration) Validate() error {
if c.Mtu < 0 {
return ErrInvalidMtu(c.Mtu)
}
// If bridge v4 subnet is specified
if c.AddressIPv4 != nil {
// If default gw is specified, it must be part of bridge subnet
if c.DefaultGatewayIPv4 != nil {
if !c.AddressIPv4.Contains(c.DefaultGatewayIPv4) {
return &ErrInvalidGateway{}
}
}
}
if c.EnableIPv6 {
// If IPv6 is enabled, AddressIPv6 must have been configured.
if c.AddressIPv6 == nil {
return errdefs.System(errors.New("no IPv6 address was allocated for the bridge"))
}
// AddressIPv6 must be IPv6, and not overlap with the LL subnet prefix.
addr, ok := netiputil.ToPrefix(c.AddressIPv6)
if !ok {
return errdefs.InvalidParameter(fmt.Errorf("invalid IPv6 address '%s'", c.AddressIPv6))
}
if err := validateIPv6Subnet(addr); err != nil {
return errdefs.InvalidParameter(err)
}
// If a default gw is specified, it must belong to AddressIPv6's subnet
if c.DefaultGatewayIPv6 != nil && !c.AddressIPv6.Contains(c.DefaultGatewayIPv6) {
return &ErrInvalidGateway{}
}
}
return nil
}
// Conflicts check if two NetworkConfiguration objects overlap
func (c *networkConfiguration) Conflicts(o *networkConfiguration) error {
if o == nil {
return errors.New("same configuration")
}
// Also empty, because only one network with empty name is allowed
if c.BridgeName == o.BridgeName {
return errors.New("networks have same bridge name")
}
// They must be in different subnets
if (c.AddressIPv4 != nil && o.AddressIPv4 != nil) &&
(c.AddressIPv4.Contains(o.AddressIPv4.IP) || o.AddressIPv4.Contains(c.AddressIPv4.IP)) {
return errors.New("networks have overlapping IPv4")
}
// They must be in different v6 subnets
if (c.AddressIPv6 != nil && o.AddressIPv6 != nil) &&
(c.AddressIPv6.Contains(o.AddressIPv6.IP) || o.AddressIPv6.Contains(c.AddressIPv6.IP)) {
return errors.New("networks have overlapping IPv6")
}
return nil
}
func (c *networkConfiguration) fromLabels(labels map[string]string) error {
var err error
for label, value := range labels {
switch label {
case BridgeName:
c.BridgeName = value
case netlabel.DriverMTU:
if c.Mtu, err = strconv.Atoi(value); err != nil {
return parseErr(label, value, err.Error())
}
case netlabel.EnableIPv6:
if c.EnableIPv6, err = strconv.ParseBool(value); err != nil {
return parseErr(label, value, err.Error())
}
case EnableIPMasquerade:
if c.EnableIPMasquerade, err = strconv.ParseBool(value); err != nil {
return parseErr(label, value, err.Error())
}
case IPv4GatewayMode:
if c.GwModeIPv4, err = newGwMode(value); err != nil {
return parseErr(label, value, err.Error())
}
case IPv6GatewayMode:
if c.GwModeIPv6, err = newGwMode(value); err != nil {
return parseErr(label, value, err.Error())
}
case EnableICC:
if c.EnableICC, err = strconv.ParseBool(value); err != nil {
return parseErr(label, value, err.Error())
}
case InhibitIPv4:
if c.InhibitIPv4, err = strconv.ParseBool(value); err != nil {
return parseErr(label, value, err.Error())
}
case DefaultBridge:
if c.DefaultBridge, err = strconv.ParseBool(value); err != nil {
return parseErr(label, value, err.Error())
}
case DefaultBindingIP:
if c.DefaultBindingIP = net.ParseIP(value); c.DefaultBindingIP == nil {
return parseErr(label, value, "nil ip")
}
case netlabel.ContainerIfacePrefix:
c.ContainerIfacePrefix = value
case netlabel.HostIPv4:
if c.HostIPv4 = net.ParseIP(value); c.HostIPv4 == nil {
return parseErr(label, value, "nil ip")
}
case netlabel.HostIPv6:
if c.HostIPv6 = net.ParseIP(value); c.HostIPv6 == nil {
return parseErr(label, value, "nil ip")
}
}
}
return nil
}
func newGwMode(gwMode string) (gwMode, error) {
switch gwMode {
case "nat":
return gwModeNAT, nil
case "routed":
return gwModeRouted, nil
}
return gwModeDefault, fmt.Errorf("unknown gateway mode %s", gwMode)
}
func (m gwMode) natDisabled() bool {
return m == gwModeRouted
}
func parseErr(label, value, errString string) error {
return types.InvalidParameterErrorf("failed to parse %s value: %v (%s)", label, value, errString)
}
func (n *bridgeNetwork) registerIptCleanFunc(clean iptableCleanFunc) {
n.iptCleanFuncs = append(n.iptCleanFuncs, clean)
}
func (n *bridgeNetwork) iptablesEnabled(version iptables.IPVersion) (bool, error) {
n.Lock()
defer n.Unlock()
if n.driver == nil {
return false, types.InvalidParameterErrorf("no driver found")
}
n.driver.Lock()
defer n.driver.Unlock()
if version == iptables.IPv6 {
return n.driver.config.EnableIP6Tables, nil
}
return n.driver.config.EnableIPTables, nil
}
func (n *bridgeNetwork) getDriverChains(version iptables.IPVersion) (*iptables.ChainInfo, *iptables.ChainInfo, *iptables.ChainInfo, *iptables.ChainInfo, error) {
n.Lock()
defer n.Unlock()
if n.driver == nil {
return nil, nil, nil, nil, types.InvalidParameterErrorf("no driver found")
}
if version == iptables.IPv6 {
return n.driver.natChainV6, n.driver.filterChainV6, n.driver.isolationChain1V6, n.driver.isolationChain2V6, nil
}
return n.driver.natChain, n.driver.filterChain, n.driver.isolationChain1, n.driver.isolationChain2, nil
}
func (n *bridgeNetwork) getNetworkBridgeName() string {
n.Lock()
config := n.config
n.Unlock()
return config.BridgeName
}
func (n *bridgeNetwork) getNATDisabled() (ipv4, ipv6 bool) {
n.Lock()
defer n.Unlock()
return n.config.GwModeIPv4.natDisabled(), n.config.GwModeIPv6.natDisabled()
}
func (n *bridgeNetwork) userlandProxyPath() string {
n.Lock()
defer n.Unlock()
if n.driver == nil {
return ""
}
return n.driver.userlandProxyPath()
}
func (n *bridgeNetwork) getPortDriverClient() portDriverClient {
n.Lock()
defer n.Unlock()
if n.driver == nil {
return nil
}
return n.driver.getPortDriverClient()
}
func (n *bridgeNetwork) getEndpoint(eid string) (*bridgeEndpoint, error) {
if eid == "" {
return nil, InvalidEndpointIDError(eid)
}
n.Lock()
defer n.Unlock()
if ep, ok := n.endpoints[eid]; ok {
return ep, nil
}
return nil, nil
}
// Install/Removes the iptables rules needed to isolate this network
// from each of the other networks
func (n *bridgeNetwork) isolateNetwork(enable bool) error {
n.Lock()
thisConfig := n.config
n.Unlock()
if thisConfig.Internal {
return nil
}
// Install the rules to isolate this network against each of the other networks
if n.driver.config.EnableIP6Tables {
err := setINC(iptables.IPv6, thisConfig.BridgeName, enable)
if err != nil {
return err
}
}
if n.driver.config.EnableIPTables {
return setINC(iptables.IPv4, thisConfig.BridgeName, enable)
}
return nil
}
func (d *driver) configure(option map[string]interface{}) error {
var (
config configuration
err error
natChain *iptables.ChainInfo
filterChain *iptables.ChainInfo
isolationChain1 *iptables.ChainInfo
isolationChain2 *iptables.ChainInfo
natChainV6 *iptables.ChainInfo
filterChainV6 *iptables.ChainInfo
isolationChain1V6 *iptables.ChainInfo
isolationChain2V6 *iptables.ChainInfo
pdc portDriverClient
)
switch opt := option[netlabel.GenericData].(type) {
case options.Generic:
opaqueConfig, err := options.GenerateFromModel(opt, &configuration{})
if err != nil {
return err
}
config = *opaqueConfig.(*configuration)
case *configuration:
config = *opt
case nil:
// No GenericData option set. Use defaults.
default:
return &ErrInvalidDriverConfig{}
}
if config.EnableIPTables || config.EnableIP6Tables {
if _, err := os.Stat("/proc/sys/net/bridge"); err != nil {
if out, err := exec.Command("modprobe", "-va", "bridge", "br_netfilter").CombinedOutput(); err != nil {
log.G(context.TODO()).Warnf("Running modprobe bridge br_netfilter failed with message: %s, error: %v", out, err)
}
}
}
if config.EnableIPTables {
removeIPChains(iptables.IPv4)
natChain, filterChain, isolationChain1, isolationChain2, err = setupIPChains(config, iptables.IPv4)
if err != nil {
return err
}
// Make sure on firewall reload, first thing being re-played is chains creation
iptables.OnReloaded(func() {
log.G(context.TODO()).Debugf("Recreating iptables chains on firewall reload")
if _, _, _, _, err := setupIPChains(config, iptables.IPv4); err != nil {
log.G(context.TODO()).WithError(err).Error("Error reloading iptables chains")
}
})
}
if config.EnableIP6Tables {
removeIPChains(iptables.IPv6)
natChainV6, filterChainV6, isolationChain1V6, isolationChain2V6, err = setupIPChains(config, iptables.IPv6)
if err != nil {
// If the chains couldn't be set up, it's probably because the kernel has no IPv6
// support, or it doesn't have module ip6_tables loaded. It won't be possible to
// create IPv6 networks without enabling ip6_tables in the kernel, or disabling
// ip6tables in the daemon config. But, allow the daemon to start because IPv4
// will work. So, log the problem, and continue.
log.G(context.TODO()).WithError(err).Warn("ip6tables is enabled, but cannot set up ip6tables chains")
} else {
// Make sure on firewall reload, first thing being re-played is chains creation
iptables.OnReloaded(func() {
log.G(context.TODO()).Debugf("Recreating ip6tables chains on firewall reload")
if _, _, _, _, err := setupIPChains(config, iptables.IPv6); err != nil {
log.G(context.TODO()).WithError(err).Error("Error reloading ip6tables chains")
}
})
}
}
if config.EnableIPForwarding {
err = setupIPForwarding(config.EnableIPTables, config.EnableIP6Tables)
if err != nil {
log.G(context.TODO()).Warn(err)
return err
}
}
if config.Rootless {
var err error
pdc, err = newPortDriverClient(context.TODO())
if err != nil {
return err
}
}
d.Lock()
d.natChain = natChain
d.filterChain = filterChain
d.isolationChain1 = isolationChain1
d.isolationChain2 = isolationChain2
d.natChainV6 = natChainV6
d.filterChainV6 = filterChainV6
d.isolationChain1V6 = isolationChain1V6
d.isolationChain2V6 = isolationChain2V6
d.portDriverClient = pdc
d.config = config
d.Unlock()
return d.initStore(option)
}
func (d *driver) getNetwork(id string) (*bridgeNetwork, error) {
d.Lock()
defer d.Unlock()
if id == "" {
return nil, types.InvalidParameterErrorf("invalid network id: %s", id)
}
if nw, ok := d.networks[id]; ok {
return nw, nil
}
return nil, types.NotFoundErrorf("network not found: %s", id)
}
func (d *driver) userlandProxyPath() string {
d.Lock()
defer d.Unlock()
if d.config.EnableUserlandProxy {
return d.config.UserlandProxyPath
}
return ""
}
func (d *driver) getPortDriverClient() portDriverClient {
d.Lock()
defer d.Unlock()
return d.portDriverClient
}
func parseNetworkGenericOptions(data interface{}) (*networkConfiguration, error) {
var (
err error
config *networkConfiguration
)
switch opt := data.(type) {
case *networkConfiguration:
config = opt
case map[string]string:
config = &networkConfiguration{
EnableICC: true,
EnableIPMasquerade: true,
}
err = config.fromLabels(opt)
case options.Generic:
var opaqueConfig interface{}
if opaqueConfig, err = options.GenerateFromModel(opt, config); err == nil {
config = opaqueConfig.(*networkConfiguration)
}
default:
err = types.InvalidParameterErrorf("do not recognize network configuration format: %T", opt)
}
return config, err
}
func (c *networkConfiguration) processIPAM(id string, ipamV4Data, ipamV6Data []driverapi.IPAMData) error {
if len(ipamV4Data) > 1 || len(ipamV6Data) > 1 {
return types.ForbiddenErrorf("bridge driver doesn't support multiple subnets")
}
if len(ipamV4Data) == 0 {
return types.InvalidParameterErrorf("bridge network %s requires ipv4 configuration", id)
}
if ipamV4Data[0].Gateway != nil {
c.AddressIPv4 = types.GetIPNetCopy(ipamV4Data[0].Gateway)
}
if gw, ok := ipamV4Data[0].AuxAddresses[DefaultGatewayV4AuxKey]; ok {
c.DefaultGatewayIPv4 = gw.IP
}
if len(ipamV6Data) > 0 {
c.AddressIPv6 = ipamV6Data[0].Pool
if ipamV6Data[0].Gateway != nil {
c.AddressIPv6 = types.GetIPNetCopy(ipamV6Data[0].Gateway)
}
if gw, ok := ipamV6Data[0].AuxAddresses[DefaultGatewayV6AuxKey]; ok {
c.DefaultGatewayIPv6 = gw.IP
}
}
return nil
}
func parseNetworkOptions(id string, option options.Generic) (*networkConfiguration, error) {
var (
err error
config = &networkConfiguration{}
)
// Parse generic label first, config will be re-assigned
if genData, ok := option[netlabel.GenericData]; ok && genData != nil {
if config, err = parseNetworkGenericOptions(genData); err != nil {
return nil, err
}
}
// Process well-known labels next
if val, ok := option[netlabel.EnableIPv6]; ok {
config.EnableIPv6 = val.(bool)
}
if val, ok := option[netlabel.Internal]; ok {
if internal, ok := val.(bool); ok && internal {
config.Internal = true
}
}
if config.BridgeName == "" && !config.DefaultBridge {
config.BridgeName = "br-" + id[:12]
}
exists, err := bridgeInterfaceExists(config.BridgeName)
if err != nil {
return nil, err
}
if !exists {
config.BridgeIfaceCreator = ifaceCreatedByLibnetwork
} else {
config.BridgeIfaceCreator = ifaceCreatedByUser
}
config.ID = id
return config, nil
}
// Return a slice of networks over which caller can iterate safely
func (d *driver) getNetworks() []*bridgeNetwork {
d.Lock()
defer d.Unlock()
ls := make([]*bridgeNetwork, 0, len(d.networks))
for _, nw := range d.networks {
ls = append(ls, nw)
}
return ls
}
func (d *driver) NetworkAllocate(id string, option map[string]string, ipV4Data, ipV6Data []driverapi.IPAMData) (map[string]string, error) {
return nil, types.NotImplementedErrorf("not implemented")
}
func (d *driver) NetworkFree(id string) error {
return types.NotImplementedErrorf("not implemented")
}
func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key string, value []byte) {
}
func (d *driver) DecodeTableEntry(tablename string, key string, value []byte) (string, map[string]string) {
return "", nil
}
// Create a new network using bridge plugin
func (d *driver) CreateNetwork(id string, option map[string]interface{}, nInfo driverapi.NetworkInfo, ipV4Data, ipV6Data []driverapi.IPAMData) error {
if len(ipV4Data) == 0 || ipV4Data[0].Pool.String() == "0.0.0.0/0" {
return types.InvalidParameterErrorf("ipv4 pool is empty")
}
// Sanity checks
d.Lock()
if _, ok := d.networks[id]; ok {
d.Unlock()
return types.ForbiddenErrorf("network %s exists", id)
}
d.Unlock()
// Parse the config.
config, err := parseNetworkOptions(id, option)
if err != nil {
return err
}
// Add IP addresses/gateways to the configuration.
if err = config.processIPAM(id, ipV4Data, ipV6Data); err != nil {
return err
}
// Validate the configuration
if err = config.Validate(); err != nil {
return err
}
// start the critical section, from this point onward we are dealing with the list of networks
// so to be consistent we cannot allow that the list changes
d.configNetwork.Lock()
defer d.configNetwork.Unlock()
// check network conflicts
if err = d.checkConflict(config); err != nil {
return err
}
// there is no conflict, now create the network
if err = d.createNetwork(config); err != nil {
return err
}
return d.storeUpdate(context.TODO(), config)
}
func (d *driver) checkConflict(config *networkConfiguration) error {
networkList := d.getNetworks()
for _, nw := range networkList {
nw.Lock()
nwConfig := nw.config
nw.Unlock()
if err := nwConfig.Conflicts(config); err != nil {
return types.ForbiddenErrorf("cannot create network %s (%s): conflicts with network %s (%s): %s",
config.ID, config.BridgeName, nwConfig.ID, nwConfig.BridgeName, err.Error())
}
}
return nil
}
func (d *driver) createNetwork(config *networkConfiguration) (err error) {
// Initialize handle when needed
d.Lock()
if d.nlh == nil {
d.nlh = ns.NlHandle()
}
d.Unlock()
// Create or retrieve the bridge L3 interface
bridgeIface, err := newInterface(d.nlh, config)
if err != nil {
return err
}
// Create and set network handler in driver
network := &bridgeNetwork{
id: config.ID,
endpoints: make(map[string]*bridgeEndpoint),
config: config,
bridge: bridgeIface,
driver: d,
}
d.Lock()
d.networks[config.ID] = network
d.Unlock()
// On failure make sure to reset driver network handler to nil
defer func() {
if err != nil {
d.Lock()
delete(d.networks, config.ID)
d.Unlock()
}
}()
// Add inter-network communication rules.
setupNetworkIsolationRules := func(config *networkConfiguration, i *bridgeInterface) error {
if err := network.isolateNetwork(true); err != nil {
if err = network.isolateNetwork(false); err != nil {
log.G(context.TODO()).Warnf("Failed on removing the inter-network iptables rules on cleanup: %v", err)
}
return err
}
// register the cleanup function
network.registerIptCleanFunc(func() error {
return network.isolateNetwork(false)
})
return nil
}
// Prepare the bridge setup configuration
bridgeSetup := newBridgeSetup(config, bridgeIface)
// If the bridge interface doesn't exist, we need to start the setup steps
// by creating a new device and assigning it an IPv4 address.
bridgeAlreadyExists := bridgeIface.exists()
if !bridgeAlreadyExists {
bridgeSetup.queueStep(setupDevice)
bridgeSetup.queueStep(setupDefaultSysctl)
}
// For the default bridge, set expected sysctls
if config.DefaultBridge {
bridgeSetup.queueStep(setupDefaultSysctl)
}
// Always set the bridge's MTU if specified. This is purely cosmetic; a bridge's
// MTU is the min MTU of device connected to it, and MTU will be set on each
// 'veth'. But, for a non-default MTU, the bridge's MTU will look wrong until a
// container is attached.
if config.Mtu > 0 {
bridgeSetup.queueStep(setupMTU)
}
// Even if a bridge exists try to setup IPv4.
bridgeSetup.queueStep(setupBridgeIPv4)
enableIPv6Forwarding := config.EnableIPv6 && d.config.EnableIPForwarding
// Conditionally queue setup steps depending on configuration values.
for _, step := range []struct {
Condition bool
Fn setupStep
}{
// Enable IPv6 on the bridge if required. We do this even for a
// previously existing bridge, as it may be here from a previous
// installation where IPv6 wasn't supported yet and needs to be
// assigned an IPv6 link-local address.
{config.EnableIPv6, setupBridgeIPv6},
// Ensure the bridge has the expected IPv4 addresses in the case of a previously
// existing device.
{bridgeAlreadyExists && !config.InhibitIPv4, setupVerifyAndReconcileIPv4},
// Enable IPv6 Forwarding
{enableIPv6Forwarding, setupIPv6Forwarding},
// Setup Loopback Addresses Routing
{!d.config.EnableUserlandProxy, setupLoopbackAddressesRouting},
// Setup IPTables.
{d.config.EnableIPTables, network.setupIP4Tables},
// Setup IP6Tables.
{config.EnableIPv6 && d.config.EnableIP6Tables, network.setupIP6Tables},
// We want to track firewalld configuration so that
// if it is started/reloaded, the rules can be applied correctly
{d.config.EnableIPTables, network.setupFirewalld},
// same for IPv6
{config.EnableIPv6 && d.config.EnableIP6Tables, network.setupFirewalld6},
// Setup DefaultGatewayIPv4
{config.DefaultGatewayIPv4 != nil, setupGatewayIPv4},
// Setup DefaultGatewayIPv6
{config.DefaultGatewayIPv6 != nil, setupGatewayIPv6},
// Add inter-network communication rules.
{d.config.EnableIPTables || d.config.EnableIP6Tables, setupNetworkIsolationRules},
// Configure bridge networking filtering if ICC is off and IP tables are enabled
{!config.EnableICC && d.config.EnableIPTables, setupIPv4BridgeNetFiltering},
{!config.EnableICC && d.config.EnableIP6Tables, setupIPv6BridgeNetFiltering},
} {
if step.Condition {
bridgeSetup.queueStep(step.Fn)
}
}
// Apply the prepared list of steps, and abort at the first error.
bridgeSetup.queueStep(setupDeviceUp)
return bridgeSetup.apply()
}
func (d *driver) DeleteNetwork(nid string) error {
d.configNetwork.Lock()
defer d.configNetwork.Unlock()
return d.deleteNetwork(nid)
}
func (d *driver) deleteNetwork(nid string) error {
var err error
// Get network handler and remove it from driver
d.Lock()
n, ok := d.networks[nid]
d.Unlock()
if !ok {
return types.InternalMaskableErrorf("network %s does not exist", nid)
}
n.Lock()
config := n.config
n.Unlock()
// delele endpoints belong to this network
for _, ep := range n.endpoints {
if err := n.releasePorts(ep); err != nil {
log.G(context.TODO()).Warn(err)
}
if link, err := d.nlh.LinkByName(ep.srcName); err == nil {
if err := d.nlh.LinkDel(link); err != nil {
log.G(context.TODO()).WithError(err).Errorf("Failed to delete interface (%s)'s link on endpoint (%s) delete", ep.srcName, ep.id)
}
}
if err := d.storeDelete(ep); err != nil {
log.G(context.TODO()).Warnf("Failed to remove bridge endpoint %.7s from store: %v", ep.id, err)
}
}
d.Lock()
delete(d.networks, nid)
d.Unlock()
// On failure set network handler back in driver, but
// only if is not already taken over by some other thread
defer func() {
if err != nil {
d.Lock()
if _, ok := d.networks[nid]; !ok {
d.networks[nid] = n
}
d.Unlock()
}
}()
switch config.BridgeIfaceCreator {
case ifaceCreatedByLibnetwork, ifaceCreatorUnknown:
// We only delete the bridge if it was created by the bridge driver and
// it is not the default one (to keep the backward compatible behavior.)
if !config.DefaultBridge {
if err := d.nlh.LinkDel(n.bridge.Link); err != nil {
log.G(context.TODO()).Warnf("Failed to remove bridge interface %s on network %s delete: %v", config.BridgeName, nid, err)
}
}
case ifaceCreatedByUser:
// Don't delete the bridge interface if it was not created by libnetwork.
}
// clean all relevant iptables rules
for _, cleanFunc := range n.iptCleanFuncs {
if errClean := cleanFunc(); errClean != nil {
log.G(context.TODO()).Warnf("Failed to clean iptables rules for bridge network: %v", errClean)
}
}
return d.storeDelete(config)
}
func addToBridge(ctx context.Context, nlh *netlink.Handle, ifaceName, bridgeName string) error {
ctx, span := otel.Tracer("").Start(ctx, "libnetwork.drivers.bridge.addToBridge", trace.WithAttributes(
attribute.String("ifaceName", ifaceName),
attribute.String("bridgeName", bridgeName)))
defer span.End()
lnk, err := nlh.LinkByName(ifaceName)
if err != nil {
return fmt.Errorf("could not find interface %s: %v", ifaceName, err)
}
if err := nlh.LinkSetMaster(lnk, &netlink.Bridge{LinkAttrs: netlink.LinkAttrs{Name: bridgeName}}); err != nil {
log.G(ctx).WithError(err).Errorf("Failed to add %s to bridge via netlink", ifaceName)
return err
}
return nil
}
func setHairpinMode(nlh *netlink.Handle, link netlink.Link, enable bool) error {
err := nlh.LinkSetHairpin(link, enable)
if err != nil {
return fmt.Errorf("unable to set hairpin mode on %s via netlink: %v",
link.Attrs().Name, err)
}
return nil
}
func (d *driver) CreateEndpoint(ctx context.Context, nid, eid string, ifInfo driverapi.InterfaceInfo, _ map[string]interface{}) error {
if ifInfo == nil {
return errors.New("invalid interface info passed")
}
ctx, span := otel.Tracer("").Start(ctx, "libnetwork.drivers.bridge.CreateEndpoint", trace.WithAttributes(
attribute.String("nid", nid),
attribute.String("eid", eid)))
defer span.End()
// Get the network handler and make sure it exists
d.Lock()
n, ok := d.networks[nid]
dconfig := d.config
d.Unlock()
if !ok {
return types.NotFoundErrorf("network %s does not exist", nid)
}
if n == nil {
return driverapi.ErrNoNetwork(nid)
}
// Sanity check
n.Lock()
if n.id != nid {
n.Unlock()
return InvalidNetworkIDError(nid)
}
n.Unlock()
// Check if endpoint id is good and retrieve correspondent endpoint
ep, err := n.getEndpoint(eid)
if err != nil {
return err
}
// Endpoint with that id exists either on desired or other sandbox
if ep != nil {
return driverapi.ErrEndpointExists(eid)
}
// Create and add the endpoint
n.Lock()
endpoint := &bridgeEndpoint{id: eid, nid: nid}
n.endpoints[eid] = endpoint
n.Unlock()
// On failure make sure to remove the endpoint
defer func() {
if err != nil {
n.Lock()
delete(n.endpoints, eid)
n.Unlock()
}
}()
// Generate a name for what will be the host side pipe interface
hostIfName, err := netutils.GenerateIfaceName(d.nlh, vethPrefix, vethLen)
if err != nil {
return err
}
// Generate a name for what will be the sandbox side pipe interface
containerIfName, err := netutils.GenerateIfaceName(d.nlh, vethPrefix, vethLen)
if err != nil {
return err
}
// Generate and add the interface pipe host <-> sandbox
veth := &netlink.Veth{
LinkAttrs: netlink.LinkAttrs{Name: hostIfName, TxQLen: 0},
PeerName: containerIfName,
}
if err = d.nlh.LinkAdd(veth); err != nil {
return types.InternalErrorf("failed to add the host (%s) <=> sandbox (%s) pair interfaces: %v", hostIfName, containerIfName, err)
}
// Get the host side pipe interface handler
host, err := d.nlh.LinkByName(hostIfName)
if err != nil {
return types.InternalErrorf("failed to find host side interface %s: %v", hostIfName, err)
}
defer func() {
if err != nil {
if err := d.nlh.LinkDel(host); err != nil {
log.G(ctx).WithError(err).Warnf("Failed to delete host side interface (%s)'s link", hostIfName)
}
}
}()
// Get the sandbox side pipe interface handler
sbox, err := d.nlh.LinkByName(containerIfName)
if err != nil {
return types.InternalErrorf("failed to find sandbox side interface %s: %v", containerIfName, err)
}
defer func() {
if err != nil {
if err := d.nlh.LinkDel(sbox); err != nil {
log.G(ctx).WithError(err).Warnf("Failed to delete sandbox side interface (%s)'s link", containerIfName)
}
}
}()
n.Lock()
config := n.config
n.Unlock()
// Add bridge inherited attributes to pipe interfaces
if config.Mtu != 0 {
err = d.nlh.LinkSetMTU(host, config.Mtu)
if err != nil {
return types.InternalErrorf("failed to set MTU on host interface %s: %v", hostIfName, err)
}
err = d.nlh.LinkSetMTU(sbox, config.Mtu)
if err != nil {
return types.InternalErrorf("failed to set MTU on sandbox interface %s: %v", containerIfName, err)
}
}
// Attach host side pipe interface into the bridge
if err = addToBridge(ctx, d.nlh, hostIfName, config.BridgeName); err != nil {
return fmt.Errorf("adding interface %s to bridge %s failed: %v", hostIfName, config.BridgeName, err)
}
if !dconfig.EnableUserlandProxy {
err = setHairpinMode(d.nlh, host, true)
if err != nil {
return err
}
}
// Store the sandbox side pipe interface parameters
endpoint.srcName = containerIfName
endpoint.macAddress = ifInfo.MacAddress()
endpoint.addr = ifInfo.Address()
endpoint.addrv6 = ifInfo.AddressIPv6()
// We assign a default MAC address derived from the IP address to make sure
// that if a container is disconnected and reconnected in a short timeframe,
// stale ARP entries will still point to the right container.
if endpoint.macAddress == nil {
endpoint.macAddress = netutils.GenerateMACFromIP(endpoint.addr.IP)
if err := ifInfo.SetMacAddress(endpoint.macAddress); err != nil {
return err
}
}
// Up the host interface after finishing all netlink configuration
if err = d.linkUp(ctx, host); err != nil {
return fmt.Errorf("could not set link up for host interface %s: %v", hostIfName, err)
}
if endpoint.addrv6 == nil && config.EnableIPv6 {
var ip6 net.IP
network := n.bridge.bridgeIPv6
if config.AddressIPv6 != nil {
network = config.AddressIPv6
}
ones, _ := network.Mask.Size()
if ones > 80 {
err = types.ForbiddenErrorf("Cannot self generate an IPv6 address on network %v: At least 48 host bits are needed.", network)
return err
}
ip6 = make(net.IP, len(network.IP))
copy(ip6, network.IP)
for i, h := range endpoint.macAddress {
ip6[i+10] = h
}
endpoint.addrv6 = &net.IPNet{IP: ip6, Mask: network.Mask}
if err = ifInfo.SetIPAddress(endpoint.addrv6); err != nil {
return err
}
}
if err = d.storeUpdate(ctx, endpoint); err != nil {
return fmt.Errorf("failed to save bridge endpoint %.7s to store: %v", endpoint.id, err)
}
return nil
}
func (d *driver) linkUp(ctx context.Context, host netlink.Link) error {
ctx, span := otel.Tracer("").Start(ctx, "libnetwork.drivers.bridge.linkUp", trace.WithAttributes(
attribute.String("host", host.Attrs().Name)))
defer span.End()
return d.nlh.LinkSetUp(host)
}
func (d *driver) DeleteEndpoint(nid, eid string) error {
var err error
// Get the network handler and make sure it exists
d.Lock()
n, ok := d.networks[nid]
d.Unlock()
if !ok {
return types.InternalMaskableErrorf("network %s does not exist", nid)
}
if n == nil {
return driverapi.ErrNoNetwork(nid)
}
// Sanity Check
n.Lock()
if n.id != nid {
n.Unlock()
return InvalidNetworkIDError(nid)
}
n.Unlock()
// Check endpoint id and if an endpoint is actually there
ep, err := n.getEndpoint(eid)
if err != nil {
return err
}
if ep == nil {
return EndpointNotFoundError(eid)
}
// Remove it
n.Lock()
delete(n.endpoints, eid)
n.Unlock()
// On failure make sure to set back ep in n.endpoints, but only
// if it hasn't been taken over already by some other thread.
defer func() {
if err != nil {
n.Lock()
if _, ok := n.endpoints[eid]; !ok {
n.endpoints[eid] = ep
}
n.Unlock()
}
}()
// Try removal of link. Discard error: it is a best effort.
// Also make sure defer does not see this error either.
if link, err := d.nlh.LinkByName(ep.srcName); err == nil {
if err := d.nlh.LinkDel(link); err != nil {
log.G(context.TODO()).WithError(err).Errorf("Failed to delete interface (%s)'s link on endpoint (%s) delete", ep.srcName, ep.id)
}
}
if err := d.storeDelete(ep); err != nil {
log.G(context.TODO()).Warnf("Failed to remove bridge endpoint %.7s from store: %v", ep.id, err)
}
return nil
}
func (d *driver) EndpointOperInfo(nid, eid string) (map[string]interface{}, error) {
// Get the network handler and make sure it exists
d.Lock()
n, ok := d.networks[nid]
d.Unlock()
if !ok {
return nil, types.NotFoundErrorf("network %s does not exist", nid)
}
if n == nil {
return nil, driverapi.ErrNoNetwork(nid)
}
// Sanity check
n.Lock()
if n.id != nid {
n.Unlock()
return nil, InvalidNetworkIDError(nid)
}
n.Unlock()
// Check if endpoint id is good and retrieve correspondent endpoint
ep, err := n.getEndpoint(eid)
if err != nil {
return nil, err
}
if ep == nil {
return nil, driverapi.ErrNoEndpoint(eid)
}
m := make(map[string]interface{})
if ep.extConnConfig != nil && ep.extConnConfig.ExposedPorts != nil {
// Return a copy of the config data
epc := make([]types.TransportPort, 0, len(ep.extConnConfig.ExposedPorts))
for _, tp := range ep.extConnConfig.ExposedPorts {
epc = append(epc, tp.GetCopy())
}
m[netlabel.ExposedPorts] = epc
}
if ep.portMapping != nil {
// Return a copy of the operational data
pmc := make([]types.PortBinding, 0, len(ep.portMapping))
for _, pm := range ep.portMapping {
pmc = append(pmc, pm.PortBinding.GetCopy())
}
m[netlabel.PortMap] = pmc
}
if len(ep.macAddress) != 0 {
m[netlabel.MacAddress] = ep.macAddress
}
return m, nil
}
// Join method is invoked when a Sandbox is attached to an endpoint.
func (d *driver) Join(ctx context.Context, nid, eid string, sboxKey string, jinfo driverapi.JoinInfo, options map[string]interface{}) error {
ctx, span := otel.Tracer("").Start(ctx, "libnetwork.drivers.bridge.Join", trace.WithAttributes(
attribute.String("nid", nid),
attribute.String("eid", eid),
attribute.String("sboxKey", sboxKey)))
defer span.End()
network, err := d.getNetwork(nid)
if err != nil {
return err
}
endpoint, err := network.getEndpoint(eid)
if err != nil {
return err
}
if endpoint == nil {
return EndpointNotFoundError(eid)
}
endpoint.containerConfig, err = parseContainerOptions(options)
if err != nil {
return err
}
iNames := jinfo.InterfaceName()
containerVethPrefix := defaultContainerVethPrefix
if network.config.ContainerIfacePrefix != "" {
containerVethPrefix = network.config.ContainerIfacePrefix
}
if err := iNames.SetNames(endpoint.srcName, containerVethPrefix); err != nil {
return err
}
if !network.config.Internal {
if err := jinfo.SetGateway(network.bridge.gatewayIPv4); err != nil {
return err
}
if err := jinfo.SetGatewayIPv6(network.bridge.gatewayIPv6); err != nil {
return err
}
}
return nil
}
// Leave method is invoked when a Sandbox detaches from an endpoint.
func (d *driver) Leave(nid, eid string) error {
network, err := d.getNetwork(nid)
if err != nil {
return types.InternalMaskableErrorf("%s", err)
}
endpoint, err := network.getEndpoint(eid)
if err != nil {
return err
}
if endpoint == nil {
return EndpointNotFoundError(eid)
}
if !network.config.EnableICC {
if err = d.link(network, endpoint, false); err != nil {
return err
}
}
return nil
}
func (d *driver) ProgramExternalConnectivity(ctx context.Context, nid, eid string, options map[string]interface{}) error {
ctx, span := otel.Tracer("").Start(ctx, "libnetwork.drivers.bridge.ProgramExternalConnectivity", trace.WithAttributes(
attribute.String("nid", nid),
attribute.String("eid", eid)))
defer span.End()
network, err := d.getNetwork(nid)
if err != nil {
return err
}
endpoint, err := network.getEndpoint(eid)
if err != nil {
return err
}
if endpoint == nil {
return EndpointNotFoundError(eid)
}
endpoint.extConnConfig, err = parseConnectivityOptions(options)
if err != nil {
return err
}
// Program any required port mapping and store them in the endpoint
if endpoint.extConnConfig != nil && endpoint.extConnConfig.PortBindings != nil {
endpoint.portMapping, err = network.addPortMappings(
endpoint.addr,
endpoint.addrv6,
endpoint.extConnConfig.PortBindings,
network.config.DefaultBindingIP,
)
if err != nil {
return err
}
}
defer func() {
if err != nil {
if e := network.releasePorts(endpoint); e != nil {
log.G(ctx).Errorf("Failed to release ports allocated for the bridge endpoint %s on failure %v because of %v",
eid, err, e)
}
endpoint.portMapping = nil
}
}()
// Clean the connection tracker state of the host for the specific endpoint. This is needed because some flows may
// be bound to the local proxy, or to the host (for UDP packets), and won't be redirected to the new endpoints.
clearConntrackEntries(d.nlh, endpoint)
if err = d.storeUpdate(ctx, endpoint); err != nil {
return fmt.Errorf("failed to update bridge endpoint %.7s to store: %v", endpoint.id, err)
}
if !network.config.EnableICC {
return d.link(network, endpoint, true)
}
return nil
}
func (d *driver) RevokeExternalConnectivity(nid, eid string) error {
network, err := d.getNetwork(nid)
if err != nil {
return err
}
endpoint, err := network.getEndpoint(eid)
if err != nil {
return err
}
if endpoint == nil {
return EndpointNotFoundError(eid)
}
err = network.releasePorts(endpoint)
if err != nil {
log.G(context.TODO()).Warn(err)
}
endpoint.portMapping = nil
// Clean the connection tracker state of the host for the specific endpoint. This is a precautionary measure to
// avoid new endpoints getting the same IP address to receive unexpected packets due to bad conntrack state leading
// to bad NATing.
clearConntrackEntries(d.nlh, endpoint)
if err = d.storeUpdate(context.TODO(), endpoint); err != nil {
return fmt.Errorf("failed to update bridge endpoint %.7s to store: %v", endpoint.id, err)
}
return nil
}
func (d *driver) link(network *bridgeNetwork, endpoint *bridgeEndpoint, enable bool) (retErr error) {
cc := endpoint.containerConfig
ec := endpoint.extConnConfig
if cc == nil || ec == nil || (len(cc.ParentEndpoints) == 0 && len(cc.ChildEndpoints) == 0) {
// nothing to do
return nil
}
// Try to keep things atomic. addedLinks keeps track of links that were
// successfully added. If any error occurred, then roll back all.
var addedLinks []*link
defer func() {
if retErr == nil {
return
}
for _, l := range addedLinks {
l.Disable()
}
}()
if ec.ExposedPorts != nil {
for _, p := range cc.ParentEndpoints {
parentEndpoint, err := network.getEndpoint(p)
if err != nil {
return err
}
if parentEndpoint == nil {
return InvalidEndpointIDError(p)
}
l, err := newLink(parentEndpoint.addr.IP, endpoint.addr.IP, ec.ExposedPorts, network.config.BridgeName)
if err != nil {
return err
}
if enable {
if err := l.Enable(); err != nil {
return err
}
addedLinks = append(addedLinks, l)
} else {
l.Disable()
}
}
}
for _, c := range cc.ChildEndpoints {
childEndpoint, err := network.getEndpoint(c)
if err != nil {
return err
}
if childEndpoint == nil {
return InvalidEndpointIDError(c)
}
if childEndpoint.extConnConfig == nil || childEndpoint.extConnConfig.ExposedPorts == nil {
continue
}
l, err := newLink(endpoint.addr.IP, childEndpoint.addr.IP, childEndpoint.extConnConfig.ExposedPorts, network.config.BridgeName)
if err != nil {
return err
}
if enable {
if err := l.Enable(); err != nil {
return err
}
addedLinks = append(addedLinks, l)
} else {
l.Disable()
}
}
return nil
}
func (d *driver) Type() string {
return NetworkType
}
func (d *driver) IsBuiltIn() bool {
return true
}
func parseContainerOptions(cOptions map[string]interface{}) (*containerConfiguration, error) {
if cOptions == nil {
return nil, nil
}
genericData := cOptions[netlabel.GenericData]
if genericData == nil {
return nil, nil
}
switch opt := genericData.(type) {
case options.Generic:
opaqueConfig, err := options.GenerateFromModel(opt, &containerConfiguration{})
if err != nil {
return nil, err
}
return opaqueConfig.(*containerConfiguration), nil
case *containerConfiguration:
return opt, nil
default:
return nil, nil
}
}
func parseConnectivityOptions(cOptions map[string]interface{}) (*connectivityConfiguration, error) {
if cOptions == nil {
return nil, nil
}
cc := &connectivityConfiguration{}
if opt, ok := cOptions[netlabel.PortMap]; ok {
if pb, ok := opt.([]types.PortBinding); ok {
cc.PortBindings = pb
} else {
return nil, types.InvalidParameterErrorf("invalid port mapping data in connectivity configuration: %v", opt)
}
}
if opt, ok := cOptions[netlabel.ExposedPorts]; ok {
if ports, ok := opt.([]types.TransportPort); ok {
cc.ExposedPorts = ports
} else {
return nil, types.InvalidParameterErrorf("invalid exposed ports data in connectivity configuration: %v", opt)
}
}
return cc, nil
}