mirror of
https://github.com/moby/moby.git
synced 2026-01-11 18:51:37 +00:00
68 lines
2.1 KiB
Go
68 lines
2.1 KiB
Go
package libnetwork
|
|
|
|
import (
|
|
"context"
|
|
"errors"
|
|
"fmt"
|
|
"os"
|
|
|
|
"github.com/containerd/log"
|
|
"github.com/docker/docker/libnetwork/internal/nftables"
|
|
"github.com/docker/docker/libnetwork/iptables"
|
|
)
|
|
|
|
const userChain = "DOCKER-USER"
|
|
|
|
func (c *Controller) selectFirewallBackend() {
|
|
// Only try to use nftables if explicitly enabled by env-var.
|
|
// TODO(robmry) - command line options?
|
|
if os.Getenv("DOCKER_FIREWALL_BACKEND") == "nftables" {
|
|
_ = nftables.Enable()
|
|
}
|
|
}
|
|
|
|
// Sets up the DOCKER-USER chain for each iptables version (IPv4, IPv6) that's
|
|
// enabled in the controller's configuration.
|
|
func (c *Controller) setupUserChains() {
|
|
// There's no equivalent to DOCKER-USER in the nftables implementation.
|
|
if nftables.Enabled() {
|
|
return
|
|
}
|
|
|
|
setup := func() error {
|
|
var errs []error
|
|
for _, ipVersion := range c.enabledIptablesVersions() {
|
|
errs = append(errs, setupUserChain(ipVersion))
|
|
}
|
|
return errors.Join(errs...)
|
|
}
|
|
if err := setup(); err != nil {
|
|
log.G(context.Background()).WithError(err).Warn("configuring " + userChain)
|
|
}
|
|
iptables.OnReloaded(func() {
|
|
if err := setup(); err != nil {
|
|
log.G(context.Background()).WithError(err).Warn("configuring " + userChain + " on firewall reload")
|
|
}
|
|
})
|
|
}
|
|
|
|
// setupUserChain sets up the DOCKER-USER chain for the given [iptables.IPVersion].
|
|
//
|
|
// This chain allows users to configure firewall policies in a way that
|
|
// persist daemon operations/restarts. The daemon does not delete or modify
|
|
// any pre-existing rules from the DOCKER-USER filter chain.
|
|
//
|
|
// Once the DOCKER-USER chain is created, the daemon does not remove it when
|
|
// IPTableForwarding is disabled, because it contains rules configured by user
|
|
// that are beyond the daemon's control.
|
|
func setupUserChain(ipVersion iptables.IPVersion) error {
|
|
ipt := iptables.GetIptable(ipVersion)
|
|
if _, err := ipt.NewChain(userChain, iptables.Filter); err != nil {
|
|
return fmt.Errorf("failed to create %s %v chain: %v", userChain, ipVersion, err)
|
|
}
|
|
if err := ipt.EnsureJumpRule("FORWARD", userChain); err != nil {
|
|
return fmt.Errorf("failed to ensure the jump rule for %s %v: %w", userChain, ipVersion, err)
|
|
}
|
|
return nil
|
|
}
|