| 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 loadbalancer 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 | |
| } |