Пример #1
0
func reexecSetupResolver() {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	if len(os.Args) < 4 {
		log.Error("invalid number of arguments..")
		os.Exit(1)
	}

	resolverIP, ipPort, _ := net.SplitHostPort(os.Args[2])
	_, tcpPort, _ := net.SplitHostPort(os.Args[3])
	rules := [][]string{
		{"-t", "nat", "-I", outputChain, "-d", resolverIP, "-p", "udp", "--dport", dnsPort, "-j", "DNAT", "--to-destination", os.Args[2]},
		{"-t", "nat", "-I", postroutingchain, "-s", resolverIP, "-p", "udp", "--sport", ipPort, "-j", "SNAT", "--to-source", ":" + dnsPort},
		{"-t", "nat", "-I", outputChain, "-d", resolverIP, "-p", "tcp", "--dport", dnsPort, "-j", "DNAT", "--to-destination", os.Args[3]},
		{"-t", "nat", "-I", postroutingchain, "-s", resolverIP, "-p", "tcp", "--sport", tcpPort, "-j", "SNAT", "--to-source", ":" + dnsPort},
	}

	f, err := os.OpenFile(os.Args[1], os.O_RDONLY, 0)
	if err != nil {
		log.Errorf("failed get network namespace %q: %v", os.Args[1], err)
		os.Exit(2)
	}
	defer f.Close()

	nsFD := f.Fd()
	if err = netns.Set(netns.NsHandle(nsFD)); err != nil {
		log.Errorf("setting into container net ns %v failed, %v", os.Args[1], err)
		os.Exit(3)
	}

	// insert outputChain and postroutingchain
	err = iptables.RawCombinedOutputNative("-t", "nat", "-C", "OUTPUT", "-d", resolverIP, "-j", outputChain)
	if err == nil {
		iptables.RawCombinedOutputNative("-t", "nat", "-F", outputChain)
	} else {
		iptables.RawCombinedOutputNative("-t", "nat", "-N", outputChain)
		iptables.RawCombinedOutputNative("-t", "nat", "-I", "OUTPUT", "-d", resolverIP, "-j", outputChain)
	}

	err = iptables.RawCombinedOutputNative("-t", "nat", "-C", "POSTROUTING", "-d", resolverIP, "-j", postroutingchain)
	if err == nil {
		iptables.RawCombinedOutputNative("-t", "nat", "-F", postroutingchain)
	} else {
		iptables.RawCombinedOutputNative("-t", "nat", "-N", postroutingchain)
		iptables.RawCombinedOutputNative("-t", "nat", "-I", "POSTROUTING", "-d", resolverIP, "-j", postroutingchain)
	}

	for _, rule := range rules {
		if iptables.RawCombinedOutputNative(rule...) != nil {
			log.Errorf("setting up rule failed, %v", rule)
		}
	}
}
Пример #2
0
// Redirecter reexec function.
func redirecter() {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	if len(os.Args) < 4 {
		logrus.Error("invalid number of arguments..")
		os.Exit(1)
	}

	var ingressPorts []*PortConfig
	if os.Args[3] != "" {
		var err error
		ingressPorts, err = readPortsFromFile(os.Args[3])
		if err != nil {
			logrus.Errorf("Failed reading ingress ports file: %v", err)
			os.Exit(2)
		}
	}

	eIP, _, err := net.ParseCIDR(os.Args[2])
	if err != nil {
		logrus.Errorf("Failed to parse endpoint IP %s: %v", os.Args[2], err)
		os.Exit(3)
	}

	rules := [][]string{}
	for _, iPort := range ingressPorts {
		rule := strings.Fields(fmt.Sprintf("-t nat -A PREROUTING -d %s -p %s --dport %d -j REDIRECT --to-port %d",
			eIP.String(), strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)]), iPort.PublishedPort, iPort.TargetPort))
		rules = append(rules, rule)
	}

	ns, err := netns.GetFromPath(os.Args[1])
	if err != nil {
		logrus.Errorf("failed get network namespace %q: %v", os.Args[1], err)
		os.Exit(4)
	}
	defer ns.Close()

	if err := netns.Set(ns); err != nil {
		logrus.Errorf("setting into container net ns %v failed, %v", os.Args[1], err)
		os.Exit(5)
	}

	for _, rule := range rules {
		if err := iptables.RawCombinedOutputNative(rule...); err != nil {
			logrus.Errorf("setting up rule failed, %v: %v", rule, err)
			os.Exit(5)
		}
	}
}
Пример #3
0
func (r *resolver) SetupFunc() func() {
	return (func() {
		var err error

		// DNS operates primarily on UDP
		addr := &net.UDPAddr{
			IP: net.ParseIP(resolverIP),
		}

		r.conn, err = net.ListenUDP("udp", addr)
		if err != nil {
			r.err = fmt.Errorf("error in opening name server socket %v", err)
			return
		}
		laddr := r.conn.LocalAddr()
		_, ipPort, _ := net.SplitHostPort(laddr.String())

		// Listen on a TCP as well
		tcpaddr := &net.TCPAddr{
			IP: net.ParseIP(resolverIP),
		}

		r.tcpListen, err = net.ListenTCP("tcp", tcpaddr)
		if err != nil {
			r.err = fmt.Errorf("error in opening name TCP server socket %v", err)
			return
		}
		ltcpaddr := r.tcpListen.Addr()
		_, tcpPort, _ := net.SplitHostPort(ltcpaddr.String())
		rules := [][]string{
			{"-t", "nat", "-A", "OUTPUT", "-d", resolverIP, "-p", "udp", "--dport", dnsPort, "-j", "DNAT", "--to-destination", laddr.String()},
			{"-t", "nat", "-A", "POSTROUTING", "-s", resolverIP, "-p", "udp", "--sport", ipPort, "-j", "SNAT", "--to-source", ":" + dnsPort},
			{"-t", "nat", "-A", "OUTPUT", "-d", resolverIP, "-p", "tcp", "--dport", dnsPort, "-j", "DNAT", "--to-destination", ltcpaddr.String()},
			{"-t", "nat", "-A", "POSTROUTING", "-s", resolverIP, "-p", "tcp", "--sport", tcpPort, "-j", "SNAT", "--to-source", ":" + dnsPort},
		}

		for _, rule := range rules {
			r.err = iptables.RawCombinedOutputNative(rule...)
			if r.err != nil {
				return
			}
		}
		r.err = nil
	})
}
Пример #4
0
// Firewall marker reexec function.
func fwMarker() {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	if len(os.Args) < 7 {
		logrus.Error("invalid number of arguments..")
		os.Exit(1)
	}

	var ingressPorts []*PortConfig
	if os.Args[5] != "" {
		buf, err := ioutil.ReadFile(os.Args[5])
		if err != nil {
			logrus.Errorf("Failed to read ports config file: %v", err)
			os.Exit(6)
		}

		var epRec EndpointRecord
		err = proto.Unmarshal(buf, &epRec)
		if err != nil {
			logrus.Errorf("Failed to unmarshal ports config data: %v", err)
			os.Exit(7)
		}

		ingressPorts = epRec.IngressPorts
	}

	vip := os.Args[2]
	fwMark, err := strconv.ParseUint(os.Args[3], 10, 32)
	if err != nil {
		logrus.Errorf("bad fwmark value(%s) passed: %v", os.Args[3], err)
		os.Exit(2)
	}
	addDelOpt := os.Args[4]

	rules := [][]string{}
	for _, iPort := range ingressPorts {
		rule := strings.Fields(fmt.Sprintf("-t nat %s PREROUTING -p %s --dport %d -j REDIRECT --to-port %d",
			addDelOpt, strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)]), iPort.PublishedPort, iPort.TargetPort))
		rules = append(rules, rule)

		rule = strings.Fields(fmt.Sprintf("-t mangle %s PREROUTING -p %s --dport %d -j MARK --set-mark %d",
			addDelOpt, strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)]), iPort.PublishedPort, fwMark))
		rules = append(rules, rule)
	}

	ns, err := netns.GetFromPath(os.Args[1])
	if err != nil {
		logrus.Errorf("failed get network namespace %q: %v", os.Args[1], err)
		os.Exit(3)
	}
	defer ns.Close()

	if err := netns.Set(ns); err != nil {
		logrus.Errorf("setting into container net ns %v failed, %v", os.Args[1], err)
		os.Exit(4)
	}

	if len(ingressPorts) != 0 && addDelOpt == "-A" {
		ruleParams := strings.Fields(fmt.Sprintf("-m ipvs --ipvs -j SNAT --to-source %s", os.Args[6]))
		if !iptables.Exists("nat", "POSTROUTING", ruleParams...) {
			rule := append(strings.Fields("-t nat -A POSTROUTING"), ruleParams...)
			rules = append(rules, rule)

			err := ioutil.WriteFile("/proc/sys/net/ipv4/vs/conntrack", []byte{'1', '\n'}, 0644)
			if err != nil {
				logrus.Errorf("Failed to write to /proc/sys/net/ipv4/vs/conntrack: %v", err)
				os.Exit(8)
			}
		}
	}

	rule := strings.Fields(fmt.Sprintf("-t mangle %s OUTPUT -d %s/32 -j MARK --set-mark %d", addDelOpt, vip, fwMark))
	rules = append(rules, rule)

	for _, rule := range rules {
		if err := iptables.RawCombinedOutputNative(rule...); err != nil {
			logrus.Errorf("setting up rule failed, %v: %v", rule, err)
			os.Exit(5)
		}
	}
}
Пример #5
0
// Redirecter reexec function.
func redirecter() {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	if len(os.Args) < 4 {
		logrus.Error("invalid number of arguments..")
		os.Exit(1)
	}

	var ingressPorts []*PortConfig
	if os.Args[3] != "" {
		var err error
		ingressPorts, err = readPortsFromFile(os.Args[3])
		if err != nil {
			logrus.Errorf("Failed reading ingress ports file: %v", err)
			os.Exit(2)
		}
	}

	eIP, _, err := net.ParseCIDR(os.Args[2])
	if err != nil {
		logrus.Errorf("Failed to parse endpoint IP %s: %v", os.Args[2], err)
		os.Exit(3)
	}

	rules := [][]string{}
	for _, iPort := range ingressPorts {
		rule := strings.Fields(fmt.Sprintf("-t nat -A PREROUTING -d %s -p %s --dport %d -j REDIRECT --to-port %d",
			eIP.String(), strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)]), iPort.PublishedPort, iPort.TargetPort))
		rules = append(rules, rule)
		// Allow only incoming connections to exposed ports
		iRule := strings.Fields(fmt.Sprintf("-I INPUT -d %s -p %s --dport %d -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT",
			eIP.String(), strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)]), iPort.TargetPort))
		rules = append(rules, iRule)
		// Allow only outgoing connections from exposed ports
		oRule := strings.Fields(fmt.Sprintf("-I OUTPUT -s %s -p %s --sport %d -m conntrack --ctstate ESTABLISHED -j ACCEPT",
			eIP.String(), strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)]), iPort.TargetPort))
		rules = append(rules, oRule)
	}

	ns, err := netns.GetFromPath(os.Args[1])
	if err != nil {
		logrus.Errorf("failed get network namespace %q: %v", os.Args[1], err)
		os.Exit(4)
	}
	defer ns.Close()

	if err := netns.Set(ns); err != nil {
		logrus.Errorf("setting into container net ns %v failed, %v", os.Args[1], err)
		os.Exit(5)
	}

	for _, rule := range rules {
		if err := iptables.RawCombinedOutputNative(rule...); err != nil {
			logrus.Errorf("setting up rule failed, %v: %v", rule, err)
			os.Exit(6)
		}
	}

	if len(ingressPorts) == 0 {
		return
	}

	// Ensure blocking rules for anything else in/to ingress network
	for _, rule := range [][]string{
		{"-d", eIP.String(), "-p", "udp", "-j", "DROP"},
		{"-d", eIP.String(), "-p", "tcp", "-j", "DROP"},
	} {
		if !iptables.ExistsNative(iptables.Filter, "INPUT", rule...) {
			if err := iptables.RawCombinedOutputNative(append([]string{"-A", "INPUT"}, rule...)...); err != nil {
				logrus.Errorf("setting up rule failed, %v: %v", rule, err)
				os.Exit(7)
			}
		}
		rule[0] = "-s"
		if !iptables.ExistsNative(iptables.Filter, "OUTPUT", rule...) {
			if err := iptables.RawCombinedOutputNative(append([]string{"-A", "OUTPUT"}, rule...)...); err != nil {
				logrus.Errorf("setting up rule failed, %v: %v", rule, err)
				os.Exit(8)
			}
		}
	}
}
Пример #6
0
// Firewall marker reexec function.
func fwMarker() {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	if len(os.Args) < 7 {
		logrus.Error("invalid number of arguments..")
		os.Exit(1)
	}

	var ingressPorts []*PortConfig
	if os.Args[5] != "" {
		var err error
		ingressPorts, err = readPortsFromFile(os.Args[5])
		if err != nil {
			logrus.Errorf("Failed reading ingress ports file: %v", err)
			os.Exit(6)
		}
	}

	vip := os.Args[2]
	fwMark, err := strconv.ParseUint(os.Args[3], 10, 32)
	if err != nil {
		logrus.Errorf("bad fwmark value(%s) passed: %v", os.Args[3], err)
		os.Exit(2)
	}
	addDelOpt := os.Args[4]

	rules := [][]string{}
	for _, iPort := range ingressPorts {
		rule := strings.Fields(fmt.Sprintf("-t mangle %s PREROUTING -p %s --dport %d -j MARK --set-mark %d",
			addDelOpt, strings.ToLower(PortConfig_Protocol_name[int32(iPort.Protocol)]), iPort.PublishedPort, fwMark))
		rules = append(rules, rule)
	}

	ns, err := netns.GetFromPath(os.Args[1])
	if err != nil {
		logrus.Errorf("failed get network namespace %q: %v", os.Args[1], err)
		os.Exit(3)
	}
	defer ns.Close()

	if err := netns.Set(ns); err != nil {
		logrus.Errorf("setting into container net ns %v failed, %v", os.Args[1], err)
		os.Exit(4)
	}

	if addDelOpt == "-A" {
		eIP, subnet, err := net.ParseCIDR(os.Args[6])
		if err != nil {
			logrus.Errorf("Failed to parse endpoint IP %s: %v", os.Args[6], err)
			os.Exit(9)
		}

		ruleParams := strings.Fields(fmt.Sprintf("-m ipvs --ipvs -d %s -j SNAT --to-source %s", subnet, eIP))
		if !iptables.Exists("nat", "POSTROUTING", ruleParams...) {
			rule := append(strings.Fields("-t nat -A POSTROUTING"), ruleParams...)
			rules = append(rules, rule)

			err := ioutil.WriteFile("/proc/sys/net/ipv4/vs/conntrack", []byte{'1', '\n'}, 0644)
			if err != nil {
				logrus.Errorf("Failed to write to /proc/sys/net/ipv4/vs/conntrack: %v", err)
				os.Exit(8)
			}
		}
	}

	rule := strings.Fields(fmt.Sprintf("-t mangle %s OUTPUT -d %s/32 -j MARK --set-mark %d", addDelOpt, vip, fwMark))
	rules = append(rules, rule)

	rule = strings.Fields(fmt.Sprintf("-t nat %s OUTPUT -p icmp --icmp echo-request -d %s -j DNAT --to 127.0.0.1", addDelOpt, vip))
	rules = append(rules, rule)

	for _, rule := range rules {
		if err := iptables.RawCombinedOutputNative(rule...); err != nil {
			logrus.Errorf("setting up rule failed, %v: %v", rule, err)
			os.Exit(5)
		}
	}
}