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- package libnetwork
- import (
- "context"
- "fmt"
- "io"
- "net"
- "os"
- "path/filepath"
- "strconv"
- "strings"
- "sync"
- "syscall"
- "github.com/containerd/log"
- "github.com/docker/docker/libnetwork/iptables"
- "github.com/docker/docker/libnetwork/ns"
- "github.com/ishidawataru/sctp"
- "github.com/moby/ipvs"
- "github.com/vishvananda/netlink/nl"
- )
- // Populate all loadbalancers on the network that the passed endpoint
- // belongs to, into this sandbox.
- func (sb *Sandbox) populateLoadBalancers(ep *Endpoint) {
- // This is an interface less endpoint. Nothing to do.
- if ep.Iface() == nil {
- return
- }
- n := ep.getNetwork()
- eIP := ep.Iface().Address()
- if n.ingress {
- if err := sb.addRedirectRules(eIP, ep.ingressPorts); err != nil {
- log.G(context.TODO()).Errorf("Failed to add redirect rules for ep %s (%.7s): %v", ep.Name(), ep.ID(), err)
- }
- }
- }
- func (n *Network) findLBEndpointSandbox() (*Endpoint, *Sandbox, error) {
- // TODO: get endpoint from store? See EndpointInfo()
- var ep *Endpoint
- // Find this node's LB sandbox endpoint: there should be exactly one
- for _, e := range n.Endpoints() {
- epi := e.Info()
- if epi != nil && epi.LoadBalancer() {
- ep = e
- break
- }
- }
- if ep == nil {
- return nil, nil, fmt.Errorf("Unable to find load balancing endpoint for network %s", n.ID())
- }
- // Get the load balancer sandbox itself as well
- sb, ok := ep.getSandbox()
- if !ok {
- return nil, nil, fmt.Errorf("Unable to get sandbox for %s(%s) in for %s", ep.Name(), ep.ID(), n.ID())
- }
- sep := sb.getEndpoint(ep.ID())
- if sep == nil {
- return nil, nil, fmt.Errorf("Load balancing endpoint %s(%s) removed from %s", ep.Name(), ep.ID(), n.ID())
- }
- return sep, sb, nil
- }
- // Searches the OS sandbox for the name of the endpoint interface
- // within the sandbox. This is required for adding/removing IP
- // aliases to the interface.
- func findIfaceDstName(sb *Sandbox, ep *Endpoint) string {
- srcName := ep.Iface().SrcName()
- for _, i := range sb.osSbox.Interfaces() {
- if i.SrcName() == srcName {
- return i.DstName()
- }
- }
- return ""
- }
- // Add loadbalancer backend to the loadbalncer sandbox for the network.
- // If needed add the service as well.
- func (n *Network) addLBBackend(ip net.IP, lb *loadBalancer) {
- if len(lb.vip) == 0 {
- return
- }
- ep, sb, err := n.findLBEndpointSandbox()
- if err != nil {
- log.G(context.TODO()).Errorf("addLBBackend %s/%s: %v", n.ID(), n.Name(), err)
- return
- }
- if sb.osSbox == nil {
- return
- }
- eIP := ep.Iface().Address()
- i, err := ipvs.New(sb.Key())
- if err != nil {
- log.G(context.TODO()).Errorf("Failed to create an ipvs handle for sbox %.7s (%.7s,%s) for lb addition: %v", sb.ID(), sb.ContainerID(), sb.Key(), err)
- return
- }
- defer i.Close()
- s := &ipvs.Service{
- AddressFamily: nl.FAMILY_V4,
- FWMark: lb.fwMark,
- SchedName: ipvs.RoundRobin,
- }
- if !i.IsServicePresent(s) {
- // Add IP alias for the VIP to the endpoint
- ifName := findIfaceDstName(sb, ep)
- if ifName == "" {
- log.G(context.TODO()).Errorf("Failed find interface name for endpoint %s(%s) to create LB alias", ep.ID(), ep.Name())
- return
- }
- err := sb.osSbox.AddAliasIP(ifName, &net.IPNet{IP: lb.vip, Mask: net.CIDRMask(32, 32)})
- if err != nil {
- log.G(context.TODO()).Errorf("Failed add IP alias %s to network %s LB endpoint interface %s: %v", lb.vip, n.ID(), ifName, err)
- return
- }
- if sb.ingress {
- var gwIP net.IP
- if ep := sb.getGatewayEndpoint(); ep != nil {
- gwIP = ep.Iface().Address().IP
- }
- if err := programIngress(gwIP, lb.service.ingressPorts, false); err != nil {
- log.G(context.TODO()).Errorf("Failed to add ingress: %v", err)
- return
- }
- }
- log.G(context.TODO()).Debugf("Creating service for vip %s fwMark %d ingressPorts %#v in sbox %.7s (%.7s)", lb.vip, lb.fwMark, lb.service.ingressPorts, sb.ID(), sb.ContainerID())
- if err := sb.configureFWMark(lb.vip, lb.fwMark, lb.service.ingressPorts, eIP, false, n.loadBalancerMode); err != nil {
- log.G(context.TODO()).Errorf("Failed to add firewall mark rule in sbox %.7s (%.7s): %v", sb.ID(), sb.ContainerID(), err)
- return
- }
- if err := i.NewService(s); err != nil && err != syscall.EEXIST {
- log.G(context.TODO()).Errorf("Failed to create a new service for vip %s fwmark %d in sbox %.7s (%.7s): %v", lb.vip, lb.fwMark, sb.ID(), sb.ContainerID(), err)
- return
- }
- }
- d := &ipvs.Destination{
- AddressFamily: nl.FAMILY_V4,
- Address: ip,
- Weight: 1,
- }
- if n.loadBalancerMode == loadBalancerModeDSR {
- d.ConnectionFlags = ipvs.ConnFwdDirectRoute
- }
- // Remove the sched name before using the service to add
- // destination.
- s.SchedName = ""
- if err := i.NewDestination(s, d); err != nil && err != syscall.EEXIST {
- log.G(context.TODO()).Errorf("Failed to create real server %s for vip %s fwmark %d in sbox %.7s (%.7s): %v", ip, lb.vip, lb.fwMark, sb.ID(), sb.ContainerID(), err)
- }
- // Ensure that kernel tweaks are applied in case this is the first time
- // we've initialized ip_vs
- sb.osSbox.ApplyOSTweaks(sb.oslTypes)
- }
- // Remove loadbalancer backend the load balancing endpoint for this
- // network. If 'rmService' is true, then remove the service entry as well.
- // If 'fullRemove' is true then completely remove the entry, otherwise
- // just deweight it for now.
- func (n *Network) rmLBBackend(ip net.IP, lb *loadBalancer, rmService bool, fullRemove bool) {
- if len(lb.vip) == 0 {
- return
- }
- ep, sb, err := n.findLBEndpointSandbox()
- if err != nil {
- log.G(context.TODO()).Debugf("rmLBBackend for %s/%s: %v -- probably transient state", n.ID(), n.Name(), err)
- return
- }
- if sb.osSbox == nil {
- return
- }
- eIP := ep.Iface().Address()
- i, err := ipvs.New(sb.Key())
- if err != nil {
- log.G(context.TODO()).Errorf("Failed to create an ipvs handle for sbox %.7s (%.7s,%s) for lb removal: %v", sb.ID(), sb.ContainerID(), sb.Key(), err)
- return
- }
- defer i.Close()
- s := &ipvs.Service{
- AddressFamily: nl.FAMILY_V4,
- FWMark: lb.fwMark,
- }
- d := &ipvs.Destination{
- AddressFamily: nl.FAMILY_V4,
- Address: ip,
- Weight: 1,
- }
- if n.loadBalancerMode == loadBalancerModeDSR {
- d.ConnectionFlags = ipvs.ConnFwdDirectRoute
- }
- if fullRemove {
- if err := i.DelDestination(s, d); err != nil && err != syscall.ENOENT {
- log.G(context.TODO()).Errorf("Failed to delete real server %s for vip %s fwmark %d in sbox %.7s (%.7s): %v", ip, lb.vip, lb.fwMark, sb.ID(), sb.ContainerID(), err)
- }
- } else {
- d.Weight = 0
- if err := i.UpdateDestination(s, d); err != nil && err != syscall.ENOENT {
- log.G(context.TODO()).Errorf("Failed to set LB weight of real server %s to 0 for vip %s fwmark %d in sbox %.7s (%.7s): %v", ip, lb.vip, lb.fwMark, sb.ID(), sb.ContainerID(), err)
- }
- }
- if rmService {
- s.SchedName = ipvs.RoundRobin
- if err := i.DelService(s); err != nil && err != syscall.ENOENT {
- log.G(context.TODO()).Errorf("Failed to delete service for vip %s fwmark %d in sbox %.7s (%.7s): %v", lb.vip, lb.fwMark, sb.ID(), sb.ContainerID(), err)
- }
- if sb.ingress {
- var gwIP net.IP
- if ep := sb.getGatewayEndpoint(); ep != nil {
- gwIP = ep.Iface().Address().IP
- }
- if err := programIngress(gwIP, lb.service.ingressPorts, true); err != nil {
- log.G(context.TODO()).Errorf("Failed to delete ingress: %v", err)
- }
- }
- if err := sb.configureFWMark(lb.vip, lb.fwMark, lb.service.ingressPorts, eIP, true, n.loadBalancerMode); err != nil {
- log.G(context.TODO()).Errorf("Failed to delete firewall mark rule in sbox %.7s (%.7s): %v", sb.ID(), sb.ContainerID(), err)
- }
- // Remove IP alias from the VIP to the endpoint
- ifName := findIfaceDstName(sb, ep)
- if ifName == "" {
- log.G(context.TODO()).Errorf("Failed find interface name for endpoint %s(%s) to create LB alias", ep.ID(), ep.Name())
- return
- }
- err := sb.osSbox.RemoveAliasIP(ifName, &net.IPNet{IP: lb.vip, Mask: net.CIDRMask(32, 32)})
- if err != nil {
- log.G(context.TODO()).Errorf("Failed add IP alias %s to network %s LB endpoint interface %s: %v", lb.vip, n.ID(), ifName, err)
- }
- }
- }
- const ingressChain = "DOCKER-INGRESS"
- var (
- ingressOnce sync.Once
- ingressMu sync.Mutex // lock for operations on ingress
- ingressProxyTbl = make(map[string]io.Closer)
- portConfigMu sync.Mutex
- portConfigTbl = make(map[PortConfig]int)
- )
- func filterPortConfigs(ingressPorts []*PortConfig, isDelete bool) []*PortConfig {
- portConfigMu.Lock()
- iPorts := make([]*PortConfig, 0, len(ingressPorts))
- for _, pc := range ingressPorts {
- if isDelete {
- if cnt, ok := portConfigTbl[*pc]; ok {
- // This is the last reference to this
- // port config. Delete the port config
- // and add it to filtered list to be
- // plumbed.
- if cnt == 1 {
- delete(portConfigTbl, *pc)
- iPorts = append(iPorts, pc)
- continue
- }
- portConfigTbl[*pc] = cnt - 1
- }
- continue
- }
- if cnt, ok := portConfigTbl[*pc]; ok {
- portConfigTbl[*pc] = cnt + 1
- continue
- }
- // We are adding it for the first time. Add it to the
- // filter list to be plumbed.
- portConfigTbl[*pc] = 1
- iPorts = append(iPorts, pc)
- }
- portConfigMu.Unlock()
- return iPorts
- }
- func programIngress(gwIP net.IP, ingressPorts []*PortConfig, isDelete bool) error {
- // TODO IPv6 support
- iptable := iptables.GetIptable(iptables.IPv4)
- addDelOpt := "-I"
- rollbackAddDelOpt := "-D"
- if isDelete {
- addDelOpt = "-D"
- rollbackAddDelOpt = "-I"
- }
- ingressMu.Lock()
- defer ingressMu.Unlock()
- chainExists := iptable.ExistChain(ingressChain, iptables.Nat)
- filterChainExists := iptable.ExistChain(ingressChain, iptables.Filter)
- ingressOnce.Do(func() {
- // Flush nat table and filter table ingress chain rules during init if it
- // exists. It might contain stale rules from previous life.
- if chainExists {
- if err := iptable.RawCombinedOutput("-t", "nat", "-F", ingressChain); err != nil {
- log.G(context.TODO()).Errorf("Could not flush nat table ingress chain rules during init: %v", err)
- }
- }
- if filterChainExists {
- if err := iptable.RawCombinedOutput("-F", ingressChain); err != nil {
- log.G(context.TODO()).Errorf("Could not flush filter table ingress chain rules during init: %v", err)
- }
- }
- })
- if !isDelete {
- if !chainExists {
- if err := iptable.RawCombinedOutput("-t", "nat", "-N", ingressChain); err != nil {
- return fmt.Errorf("failed to create ingress chain: %v", err)
- }
- }
- if !filterChainExists {
- if err := iptable.RawCombinedOutput("-N", ingressChain); err != nil {
- return fmt.Errorf("failed to create filter table ingress chain: %v", err)
- }
- }
- if !iptable.Exists(iptables.Nat, ingressChain, "-j", "RETURN") {
- if err := iptable.RawCombinedOutput("-t", "nat", "-A", ingressChain, "-j", "RETURN"); err != nil {
- return fmt.Errorf("failed to add return rule in nat table ingress chain: %v", err)
- }
- }
- if !iptable.Exists(iptables.Filter, ingressChain, "-j", "RETURN") {
- if err := iptable.RawCombinedOutput("-A", ingressChain, "-j", "RETURN"); err != nil {
- return fmt.Errorf("failed to add return rule to filter table ingress chain: %v", err)
- }
- }
- for _, chain := range []string{"OUTPUT", "PREROUTING"} {
- if !iptable.Exists(iptables.Nat, chain, "-m", "addrtype", "--dst-type", "LOCAL", "-j", ingressChain) {
- if err := iptable.RawCombinedOutput("-t", "nat", "-I", chain, "-m", "addrtype", "--dst-type", "LOCAL", "-j", ingressChain); err != nil {
- return fmt.Errorf("failed to add jump rule in %s to ingress chain: %v", chain, err)
- }
- }
- }
- if !iptable.Exists(iptables.Filter, "FORWARD", "-j", ingressChain) {
- if err := iptable.RawCombinedOutput("-I", "FORWARD", "-j", ingressChain); err != nil {
- return fmt.Errorf("failed to add jump rule to %s in filter table forward chain: %v", ingressChain, err)
- }
- arrangeUserFilterRule()
- }
- oifName, err := findOIFName(gwIP)
- if err != nil {
- return fmt.Errorf("failed to find gateway bridge interface name for %s: %v", gwIP, err)
- }
- path := filepath.Join("/proc/sys/net/ipv4/conf", oifName, "route_localnet")
- if err := os.WriteFile(path, []byte{'1', '\n'}, 0o644); err != nil { //nolint:gosec // gosec complains about perms here, which must be 0644 in this case
- return fmt.Errorf("could not write to %s: %v", path, err)
- }
- ruleArgs := []string{"-m", "addrtype", "--src-type", "LOCAL", "-o", oifName, "-j", "MASQUERADE"}
- if !iptable.Exists(iptables.Nat, "POSTROUTING", ruleArgs...) {
- if err := iptable.RawCombinedOutput(append([]string{"-t", "nat", "-I", "POSTROUTING"}, ruleArgs...)...); err != nil {
- return fmt.Errorf("failed to add ingress localhost POSTROUTING rule for %s: %v", oifName, err)
- }
- }
- }
- // Filter the ingress ports until port rules start to be added/deleted
- filteredPorts := filterPortConfigs(ingressPorts, isDelete)
- rollbackRules := make([][]string, 0, len(filteredPorts)*3)
- var portErr error
- defer func() {
- if portErr != nil && !isDelete {
- filterPortConfigs(filteredPorts, !isDelete)
- for _, rule := range rollbackRules {
- if err := iptable.RawCombinedOutput(rule...); err != nil {
- log.G(context.TODO()).Warnf("roll back rule failed, %v: %v", rule, err)
- }
- }
- }
- }()
- for _, iPort := range filteredPorts {
- var (
- protocol = strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)])
- publishedPort = strconv.FormatUint(uint64(iPort.PublishedPort), 10)
- destination = net.JoinHostPort(gwIP.String(), publishedPort)
- )
- if iptable.ExistChain(ingressChain, iptables.Nat) {
- rule := []string{"-t", "nat", addDelOpt, ingressChain, "-p", protocol, "--dport", publishedPort, "-j", "DNAT", "--to-destination", destination}
- if portErr = iptable.RawCombinedOutput(rule...); portErr != nil {
- err := fmt.Errorf("set up rule failed, %v: %v", rule, portErr)
- if !isDelete {
- return err
- }
- log.G(context.TODO()).Info(err)
- }
- rollbackRule := []string{"-t", "nat", rollbackAddDelOpt, ingressChain, "-p", protocol, "--dport", publishedPort, "-j", "DNAT", "--to-destination", destination}
- rollbackRules = append(rollbackRules, rollbackRule)
- }
- // Filter table rules to allow a published service to be accessible in the local node from..
- // 1) service tasks attached to other networks
- // 2) unmanaged containers on bridge networks
- rule := []string{addDelOpt, ingressChain, "-p", protocol, "--sport", publishedPort, "-m", "conntrack", "--ctstate", "ESTABLISHED,RELATED", "-j", "ACCEPT"}
- if portErr = iptable.RawCombinedOutput(rule...); portErr != nil {
- err := fmt.Errorf("set up rule failed, %v: %v", rule, portErr)
- if !isDelete {
- return err
- }
- log.G(context.TODO()).Warn(err)
- }
- rollbackRule := []string{rollbackAddDelOpt, ingressChain, "-p", protocol, "--sport", publishedPort, "-m", "conntrack", "--ctstate", "ESTABLISHED,RELATED", "-j", "ACCEPT"}
- rollbackRules = append(rollbackRules, rollbackRule)
- rule = []string{addDelOpt, ingressChain, "-p", protocol, "--dport", publishedPort, "-j", "ACCEPT"}
- if portErr = iptable.RawCombinedOutput(rule...); portErr != nil {
- err := fmt.Errorf("set up rule failed, %v: %v", rule, portErr)
- if !isDelete {
- return err
- }
- log.G(context.TODO()).Warn(err)
- }
- rollbackRule = []string{rollbackAddDelOpt, ingressChain, "-p", protocol, "--dport", publishedPort, "-j", "ACCEPT"}
- rollbackRules = append(rollbackRules, rollbackRule)
- if err := plumbProxy(iPort, isDelete); err != nil {
- log.G(context.TODO()).Warnf("failed to create proxy for port %s: %v", publishedPort, err)
- }
- }
- return nil
- }
- // In the filter table FORWARD chain the first rule should be to jump to
- // DOCKER-USER so the user is able to filter packet first.
- // The second rule should be jump to INGRESS-CHAIN.
- // This chain has the rules to allow access to the published ports for swarm tasks
- // from local bridge networks and docker_gwbridge (ie:taks on other swarm networks)
- func arrangeIngressFilterRule() {
- // TODO IPv6 support
- iptable := iptables.GetIptable(iptables.IPv4)
- if iptable.ExistChain(ingressChain, iptables.Filter) {
- if iptable.Exists(iptables.Filter, "FORWARD", "-j", ingressChain) {
- if err := iptable.RawCombinedOutput("-D", "FORWARD", "-j", ingressChain); err != nil {
- log.G(context.TODO()).Warnf("failed to delete jump rule to ingressChain in filter table: %v", err)
- }
- }
- if err := iptable.RawCombinedOutput("-I", "FORWARD", "-j", ingressChain); err != nil {
- log.G(context.TODO()).Warnf("failed to add jump rule to ingressChain in filter table: %v", err)
- }
- }
- }
- func findOIFName(ip net.IP) (string, error) {
- nlh := ns.NlHandle()
- routes, err := nlh.RouteGet(ip)
- if err != nil {
- return "", err
- }
- if len(routes) == 0 {
- return "", fmt.Errorf("no route to %s", ip)
- }
- // Pick the first route(typically there is only one route). We
- // don't support multipath.
- link, err := nlh.LinkByIndex(routes[0].LinkIndex)
- if err != nil {
- return "", err
- }
- return link.Attrs().Name, nil
- }
- func plumbProxy(iPort *PortConfig, isDelete bool) error {
- var (
- err error
- l io.Closer
- )
- portSpec := fmt.Sprintf("%d/%s", iPort.PublishedPort, strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)]))
- if isDelete {
- if listener, ok := ingressProxyTbl[portSpec]; ok {
- if listener != nil {
- listener.Close()
- }
- }
- return nil
- }
- switch iPort.Protocol {
- case ProtocolTCP:
- l, err = net.ListenTCP("tcp", &net.TCPAddr{Port: int(iPort.PublishedPort)})
- case ProtocolUDP:
- l, err = net.ListenUDP("udp", &net.UDPAddr{Port: int(iPort.PublishedPort)})
- case ProtocolSCTP:
- l, err = sctp.ListenSCTP("sctp", &sctp.SCTPAddr{Port: int(iPort.PublishedPort)})
- default:
- err = fmt.Errorf("unknown protocol %v", iPort.Protocol)
- }
- if err != nil {
- return err
- }
- ingressProxyTbl[portSpec] = l
- return nil
- }
- // configureFWMark configures the sandbox firewall to mark vip destined packets
- // with the firewall mark fwMark.
- func (sb *Sandbox) configureFWMark(vip net.IP, fwMark uint32, ingressPorts []*PortConfig, eIP *net.IPNet, isDelete bool, lbMode string) error {
- // TODO IPv6 support
- iptable := iptables.GetIptable(iptables.IPv4)
- fwMarkStr := strconv.FormatUint(uint64(fwMark), 10)
- addDelOpt := "-A"
- if isDelete {
- addDelOpt = "-D"
- }
- rules := make([][]string, 0, len(ingressPorts))
- for _, iPort := range ingressPorts {
- var (
- protocol = strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)])
- publishedPort = strconv.FormatUint(uint64(iPort.PublishedPort), 10)
- )
- rule := []string{"-t", "mangle", addDelOpt, "PREROUTING", "-p", protocol, "--dport", publishedPort, "-j", "MARK", "--set-mark", fwMarkStr}
- rules = append(rules, rule)
- }
- var innerErr error
- err := sb.ExecFunc(func() {
- if !isDelete && lbMode == loadBalancerModeNAT {
- subnet := net.IPNet{IP: eIP.IP.Mask(eIP.Mask), Mask: eIP.Mask}
- ruleParams := []string{"-m", "ipvs", "--ipvs", "-d", subnet.String(), "-j", "SNAT", "--to-source", eIP.IP.String()}
- if !iptable.Exists("nat", "POSTROUTING", ruleParams...) {
- rule := append([]string{"-t", "nat", "-A", "POSTROUTING"}, ruleParams...)
- rules = append(rules, rule)
- err := os.WriteFile("/proc/sys/net/ipv4/vs/conntrack", []byte{'1', '\n'}, 0o644)
- if err != nil {
- innerErr = err
- return
- }
- }
- }
- rule := []string{"-t", "mangle", addDelOpt, "INPUT", "-d", vip.String() + "/32", "-j", "MARK", "--set-mark", fwMarkStr}
- rules = append(rules, rule)
- for _, rule := range rules {
- if err := iptable.RawCombinedOutputNative(rule...); err != nil {
- innerErr = fmt.Errorf("set up rule failed, %v: %w", rule, err)
- return
- }
- }
- })
- if err != nil {
- return err
- }
- return innerErr
- }
- func (sb *Sandbox) addRedirectRules(eIP *net.IPNet, ingressPorts []*PortConfig) error {
- // TODO IPv6 support
- iptable := iptables.GetIptable(iptables.IPv4)
- ipAddr := eIP.IP.String()
- rules := make([][]string, 0, len(ingressPorts)*3) // 3 rules per port
- for _, iPort := range ingressPorts {
- var (
- protocol = strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)])
- publishedPort = strconv.FormatUint(uint64(iPort.PublishedPort), 10)
- targetPort = strconv.FormatUint(uint64(iPort.TargetPort), 10)
- )
- rules = append(rules,
- []string{"-t", "nat", "-A", "PREROUTING", "-d", ipAddr, "-p", protocol, "--dport", publishedPort, "-j", "REDIRECT", "--to-port", targetPort},
- // Allow only incoming connections to exposed ports
- []string{"-I", "INPUT", "-d", ipAddr, "-p", protocol, "--dport", targetPort, "-m", "conntrack", "--ctstate", "NEW,ESTABLISHED", "-j", "ACCEPT"},
- // Allow only outgoing connections from exposed ports
- []string{"-I", "OUTPUT", "-s", ipAddr, "-p", protocol, "--sport", targetPort, "-m", "conntrack", "--ctstate", "ESTABLISHED", "-j", "ACCEPT"},
- )
- }
- var innerErr error
- err := sb.ExecFunc(func() {
- for _, rule := range rules {
- if err := iptable.RawCombinedOutputNative(rule...); err != nil {
- innerErr = fmt.Errorf("set up rule failed, %v: %w", rule, err)
- return
- }
- }
- if len(ingressPorts) == 0 {
- return
- }
- // Ensure blocking rules for anything else in/to ingress network
- for _, rule := range [][]string{
- {"-d", ipAddr, "-p", "sctp", "-j", "DROP"},
- {"-d", ipAddr, "-p", "udp", "-j", "DROP"},
- {"-d", ipAddr, "-p", "tcp", "-j", "DROP"},
- } {
- if !iptable.ExistsNative(iptables.Filter, "INPUT", rule...) {
- if err := iptable.RawCombinedOutputNative(append([]string{"-A", "INPUT"}, rule...)...); err != nil {
- innerErr = fmt.Errorf("set up rule failed, %v: %w", rule, err)
- return
- }
- }
- rule[0] = "-s"
- if !iptable.ExistsNative(iptables.Filter, "OUTPUT", rule...) {
- if err := iptable.RawCombinedOutputNative(append([]string{"-A", "OUTPUT"}, rule...)...); err != nil {
- innerErr = fmt.Errorf("set up rule failed, %v: %w", rule, err)
- return
- }
- }
- }
- })
- if err != nil {
- return err
- }
- return innerErr
- }
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