diff options
Diffstat (limited to 'test/iptables/nat.go')
-rw-r--r-- | test/iptables/nat.go | 257 |
1 files changed, 254 insertions, 3 deletions
diff --git a/test/iptables/nat.go b/test/iptables/nat.go index b5c6f927e..40096901c 100644 --- a/test/iptables/nat.go +++ b/test/iptables/nat.go @@ -15,8 +15,10 @@ package iptables import ( + "errors" "fmt" "net" + "time" ) const ( @@ -25,7 +27,16 @@ const ( func init() { RegisterTestCase(NATRedirectUDPPort{}) + RegisterTestCase(NATRedirectTCPPort{}) RegisterTestCase(NATDropUDP{}) + RegisterTestCase(NATAcceptAll{}) + RegisterTestCase(NATPreRedirectIP{}) + RegisterTestCase(NATPreDontRedirectIP{}) + RegisterTestCase(NATPreRedirectInvert{}) + RegisterTestCase(NATOutRedirectIP{}) + RegisterTestCase(NATOutDontRedirectIP{}) + RegisterTestCase(NATOutRedirectInvert{}) + RegisterTestCase(NATRedirectRequiresProtocol{}) } // NATRedirectUDPPort tests that packets are redirected to different port. @@ -38,13 +49,14 @@ func (NATRedirectUDPPort) Name() string { // ContainerAction implements TestCase.ContainerAction. func (NATRedirectUDPPort) ContainerAction(ip net.IP) error { - if err := filterTable("-t", "nat", "-A", "PREROUTING", "-p", "udp", "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil { + if err := natTable("-A", "PREROUTING", "-p", "udp", "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil { return err } if err := listenUDP(redirectPort, sendloopDuration); err != nil { return fmt.Errorf("packets on port %d should be allowed, but encountered an error: %v", redirectPort, err) } + return nil } @@ -53,7 +65,31 @@ func (NATRedirectUDPPort) LocalAction(ip net.IP) error { return sendUDPLoop(ip, acceptPort, sendloopDuration) } -// NATDropUDP tests that packets are not received in ports other than redirect port. +// NATRedirectTCPPort tests that connections are redirected on specified ports. +type NATRedirectTCPPort struct{} + +// Name implements TestCase.Name. +func (NATRedirectTCPPort) Name() string { + return "NATRedirectTCPPort" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATRedirectTCPPort) ContainerAction(ip net.IP) error { + if err := natTable("-A", "PREROUTING", "-p", "tcp", "-m", "tcp", "--dport", fmt.Sprintf("%d", dropPort), "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil { + return err + } + + // Listen for TCP packets on redirect port. + return listenTCP(redirectPort, sendloopDuration) +} + +// LocalAction implements TestCase.LocalAction. +func (NATRedirectTCPPort) LocalAction(ip net.IP) error { + return connectTCP(ip, dropPort, sendloopDuration) +} + +// NATDropUDP tests that packets are not received in ports other than redirect +// port. type NATDropUDP struct{} // Name implements TestCase.Name. @@ -63,7 +99,7 @@ func (NATDropUDP) Name() string { // ContainerAction implements TestCase.ContainerAction. func (NATDropUDP) ContainerAction(ip net.IP) error { - if err := filterTable("-t", "nat", "-A", "PREROUTING", "-p", "udp", "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil { + if err := natTable("-A", "PREROUTING", "-p", "udp", "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil { return err } @@ -78,3 +114,218 @@ func (NATDropUDP) ContainerAction(ip net.IP) error { func (NATDropUDP) LocalAction(ip net.IP) error { return sendUDPLoop(ip, acceptPort, sendloopDuration) } + +// NATAcceptAll tests that all UDP packets are accepted. +type NATAcceptAll struct{} + +// Name implements TestCase.Name. +func (NATAcceptAll) Name() string { + return "NATAcceptAll" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATAcceptAll) ContainerAction(ip net.IP) error { + if err := natTable("-A", "PREROUTING", "-p", "udp", "-j", "ACCEPT"); err != nil { + return err + } + + if err := listenUDP(acceptPort, sendloopDuration); err != nil { + return fmt.Errorf("packets on port %d should be allowed, but encountered an error: %v", acceptPort, err) + } + + return nil +} + +// LocalAction implements TestCase.LocalAction. +func (NATAcceptAll) LocalAction(ip net.IP) error { + return sendUDPLoop(ip, acceptPort, sendloopDuration) +} + +// NATOutRedirectIP uses iptables to select packets based on destination IP and +// redirects them. +type NATOutRedirectIP struct{} + +// Name implements TestCase.Name. +func (NATOutRedirectIP) Name() string { + return "NATOutRedirectIP" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATOutRedirectIP) ContainerAction(ip net.IP) error { + // Redirect OUTPUT packets to a listening localhost port. + dest := net.IP([]byte{200, 0, 0, 2}) + return loopbackTest(dest, "-A", "OUTPUT", "-d", dest.String(), "-p", "udp", "-j", "REDIRECT", "--to-port", fmt.Sprintf("%d", acceptPort)) +} + +// LocalAction implements TestCase.LocalAction. +func (NATOutRedirectIP) LocalAction(ip net.IP) error { + // No-op. + return nil +} + +// NATOutDontRedirectIP tests that iptables matching with "-d" does not match +// packets it shouldn't. +type NATOutDontRedirectIP struct{} + +// Name implements TestCase.Name. +func (NATOutDontRedirectIP) Name() string { + return "NATOutDontRedirectIP" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATOutDontRedirectIP) ContainerAction(ip net.IP) error { + if err := natTable("-A", "OUTPUT", "-d", localIP, "-p", "udp", "-j", "REDIRECT", "--to-port", fmt.Sprintf("%d", dropPort)); err != nil { + return err + } + return sendUDPLoop(ip, acceptPort, sendloopDuration) +} + +// LocalAction implements TestCase.LocalAction. +func (NATOutDontRedirectIP) LocalAction(ip net.IP) error { + return listenUDP(acceptPort, sendloopDuration) +} + +// NATOutRedirectInvert tests that iptables can match with "! -d". +type NATOutRedirectInvert struct{} + +// Name implements TestCase.Name. +func (NATOutRedirectInvert) Name() string { + return "NATOutRedirectInvert" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATOutRedirectInvert) ContainerAction(ip net.IP) error { + // Redirect OUTPUT packets to a listening localhost port. + dest := []byte{200, 0, 0, 3} + destStr := "200.0.0.2" + return loopbackTest(dest, "-A", "OUTPUT", "!", "-d", destStr, "-p", "udp", "-j", "REDIRECT", "--to-port", fmt.Sprintf("%d", acceptPort)) +} + +// LocalAction implements TestCase.LocalAction. +func (NATOutRedirectInvert) LocalAction(ip net.IP) error { + // No-op. + return nil +} + +// NATPreRedirectIP tests that we can use iptables to select packets based on +// destination IP and redirect them. +type NATPreRedirectIP struct{} + +// Name implements TestCase.Name. +func (NATPreRedirectIP) Name() string { + return "NATPreRedirectIP" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATPreRedirectIP) ContainerAction(ip net.IP) error { + addrs, err := localAddrs() + if err != nil { + return err + } + + var rules [][]string + for _, addr := range addrs { + rules = append(rules, []string{"-A", "PREROUTING", "-p", "udp", "-d", addr, "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", acceptPort)}) + } + if err := natTableRules(rules); err != nil { + return err + } + return listenUDP(acceptPort, sendloopDuration) +} + +// LocalAction implements TestCase.LocalAction. +func (NATPreRedirectIP) LocalAction(ip net.IP) error { + return sendUDPLoop(ip, dropPort, sendloopDuration) +} + +// NATPreDontRedirectIP tests that iptables matching with "-d" does not match +// packets it shouldn't. +type NATPreDontRedirectIP struct{} + +// Name implements TestCase.Name. +func (NATPreDontRedirectIP) Name() string { + return "NATPreDontRedirectIP" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATPreDontRedirectIP) ContainerAction(ip net.IP) error { + if err := natTable("-A", "PREROUTING", "-p", "udp", "-d", localIP, "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", dropPort)); err != nil { + return err + } + return listenUDP(acceptPort, sendloopDuration) +} + +// LocalAction implements TestCase.LocalAction. +func (NATPreDontRedirectIP) LocalAction(ip net.IP) error { + return sendUDPLoop(ip, acceptPort, sendloopDuration) +} + +// NATPreRedirectInvert tests that iptables can match with "! -d". +type NATPreRedirectInvert struct{} + +// Name implements TestCase.Name. +func (NATPreRedirectInvert) Name() string { + return "NATPreRedirectInvert" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATPreRedirectInvert) ContainerAction(ip net.IP) error { + if err := natTable("-A", "PREROUTING", "-p", "udp", "!", "-d", localIP, "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", acceptPort)); err != nil { + return err + } + return listenUDP(acceptPort, sendloopDuration) +} + +// LocalAction implements TestCase.LocalAction. +func (NATPreRedirectInvert) LocalAction(ip net.IP) error { + return sendUDPLoop(ip, dropPort, sendloopDuration) +} + +// NATRedirectRequiresProtocol tests that use of the --to-ports flag requires a +// protocol to be specified with -p. +type NATRedirectRequiresProtocol struct{} + +// Name implements TestCase.Name. +func (NATRedirectRequiresProtocol) Name() string { + return "NATRedirectRequiresProtocol" +} + +// ContainerAction implements TestCase.ContainerAction. +func (NATRedirectRequiresProtocol) ContainerAction(ip net.IP) error { + if err := natTable("-A", "PREROUTING", "-d", localIP, "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", acceptPort)); err == nil { + return errors.New("expected an error using REDIRECT --to-ports without a protocol") + } + return nil +} + +// LocalAction implements TestCase.LocalAction. +func (NATRedirectRequiresProtocol) LocalAction(ip net.IP) error { + // No-op. + return nil +} + +// loopbackTests runs an iptables rule and ensures that packets sent to +// dest:dropPort are received by localhost:acceptPort. +func loopbackTest(dest net.IP, args ...string) error { + if err := natTable(args...); err != nil { + return err + } + sendCh := make(chan error) + listenCh := make(chan error) + go func() { + sendCh <- sendUDPLoop(dest, dropPort, sendloopDuration) + }() + go func() { + listenCh <- listenUDP(acceptPort, sendloopDuration) + }() + select { + case err := <-listenCh: + if err != nil { + return err + } + case <-time.After(sendloopDuration): + return errors.New("timed out") + } + // sendCh will always take the full sendloop time. + return <-sendCh +} |