Libnetwork refactor for container network model

- Added controller, network, endpoint and sandbox interfaces
    - Created netutils package for miscallaneous network utilities
    - Created driverapi package to break cyclic dependency b/w driver and libnetwork
    - Made libnetwork multithread safe
    - Made bridge driver multithread safe
    - Fixed README.md

Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>

libnetwork/netutils/utils_test.go

@@ -0,0 +1,176 @@
+package netutils
+
+import (
+	"net"
+	"testing"
+
+	"github.com/vishvananda/netlink"
+)
+
+func TestNonOverlapingNameservers(t *testing.T) {
+	network := &net.IPNet{
+		IP:   []byte{192, 168, 0, 1},
+		Mask: []byte{255, 255, 255, 0},
+	}
+	nameservers := []string{
+		"127.0.0.1/32",
+	}
+
+	if err := CheckNameserverOverlaps(nameservers, network); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestOverlapingNameservers(t *testing.T) {
+	network := &net.IPNet{
+		IP:   []byte{192, 168, 0, 1},
+		Mask: []byte{255, 255, 255, 0},
+	}
+	nameservers := []string{
+		"192.168.0.1/32",
+	}
+
+	if err := CheckNameserverOverlaps(nameservers, network); err == nil {
+		t.Fatalf("Expected error %s got %s", ErrNetworkOverlapsWithNameservers, err)
+	}
+}
+
+func TestCheckRouteOverlaps(t *testing.T) {
+	orig := networkGetRoutesFct
+	defer func() {
+		networkGetRoutesFct = orig
+	}()
+	networkGetRoutesFct = func(netlink.Link, int) ([]netlink.Route, error) {
+		routesData := []string{"10.0.2.0/32", "10.0.3.0/24", "10.0.42.0/24", "172.16.42.0/24", "192.168.142.0/24"}
+
+		routes := []netlink.Route{}
+		for _, addr := range routesData {
+			_, netX, _ := net.ParseCIDR(addr)
+			routes = append(routes, netlink.Route{Dst: netX})
+		}
+		return routes, nil
+	}
+
+	_, netX, _ := net.ParseCIDR("172.16.0.1/24")
+	if err := CheckRouteOverlaps(netX); err != nil {
+		t.Fatal(err)
+	}
+
+	_, netX, _ = net.ParseCIDR("10.0.2.0/24")
+	if err := CheckRouteOverlaps(netX); err == nil {
+		t.Fatalf("10.0.2.0/24 and 10.0.2.0 should overlap but it doesn't")
+	}
+}
+
+func TestCheckNameserverOverlaps(t *testing.T) {
+	nameservers := []string{"10.0.2.3/32", "192.168.102.1/32"}
+
+	_, netX, _ := net.ParseCIDR("10.0.2.3/32")
+
+	if err := CheckNameserverOverlaps(nameservers, netX); err == nil {
+		t.Fatalf("%s should overlap 10.0.2.3/32 but doesn't", netX)
+	}
+
+	_, netX, _ = net.ParseCIDR("192.168.102.2/32")
+
+	if err := CheckNameserverOverlaps(nameservers, netX); err != nil {
+		t.Fatalf("%s should not overlap %v but it does", netX, nameservers)
+	}
+}
+
+func AssertOverlap(CIDRx string, CIDRy string, t *testing.T) {
+	_, netX, _ := net.ParseCIDR(CIDRx)
+	_, netY, _ := net.ParseCIDR(CIDRy)
+	if !NetworkOverlaps(netX, netY) {
+		t.Errorf("%v and %v should overlap", netX, netY)
+	}
+}
+
+func AssertNoOverlap(CIDRx string, CIDRy string, t *testing.T) {
+	_, netX, _ := net.ParseCIDR(CIDRx)
+	_, netY, _ := net.ParseCIDR(CIDRy)
+	if NetworkOverlaps(netX, netY) {
+		t.Errorf("%v and %v should not overlap", netX, netY)
+	}
+}
+
+func TestNetworkOverlaps(t *testing.T) {
+	//netY starts at same IP and ends within netX
+	AssertOverlap("172.16.0.1/24", "172.16.0.1/25", t)
+	//netY starts within netX and ends at same IP
+	AssertOverlap("172.16.0.1/24", "172.16.0.128/25", t)
+	//netY starts and ends within netX
+	AssertOverlap("172.16.0.1/24", "172.16.0.64/25", t)
+	//netY starts at same IP and ends outside of netX
+	AssertOverlap("172.16.0.1/24", "172.16.0.1/23", t)
+	//netY starts before and ends at same IP of netX
+	AssertOverlap("172.16.1.1/24", "172.16.0.1/23", t)
+	//netY starts before and ends outside of netX
+	AssertOverlap("172.16.1.1/24", "172.16.0.1/22", t)
+	//netY starts and ends before netX
+	AssertNoOverlap("172.16.1.1/25", "172.16.0.1/24", t)
+	//netX starts and ends before netY
+	AssertNoOverlap("172.16.1.1/25", "172.16.2.1/24", t)
+}
+
+func TestNetworkRange(t *testing.T) {
+	// Simple class C test
+	_, network, _ := net.ParseCIDR("192.168.0.1/24")
+	first, last := NetworkRange(network)
+	if !first.Equal(net.ParseIP("192.168.0.0")) {
+		t.Error(first.String())
+	}
+	if !last.Equal(net.ParseIP("192.168.0.255")) {
+		t.Error(last.String())
+	}
+
+	// Class A test
+	_, network, _ = net.ParseCIDR("10.0.0.1/8")
+	first, last = NetworkRange(network)
+	if !first.Equal(net.ParseIP("10.0.0.0")) {
+		t.Error(first.String())
+	}
+	if !last.Equal(net.ParseIP("10.255.255.255")) {
+		t.Error(last.String())
+	}
+
+	// Class A, random IP address
+	_, network, _ = net.ParseCIDR("10.1.2.3/8")
+	first, last = NetworkRange(network)
+	if !first.Equal(net.ParseIP("10.0.0.0")) {
+		t.Error(first.String())
+	}
+	if !last.Equal(net.ParseIP("10.255.255.255")) {
+		t.Error(last.String())
+	}
+
+	// 32bit mask
+	_, network, _ = net.ParseCIDR("10.1.2.3/32")
+	first, last = NetworkRange(network)
+	if !first.Equal(net.ParseIP("10.1.2.3")) {
+		t.Error(first.String())
+	}
+	if !last.Equal(net.ParseIP("10.1.2.3")) {
+		t.Error(last.String())
+	}
+
+	// 31bit mask
+	_, network, _ = net.ParseCIDR("10.1.2.3/31")
+	first, last = NetworkRange(network)
+	if !first.Equal(net.ParseIP("10.1.2.2")) {
+		t.Error(first.String())
+	}
+	if !last.Equal(net.ParseIP("10.1.2.3")) {
+		t.Error(last.String())
+	}
+
+	// 26bit mask
+	_, network, _ = net.ParseCIDR("10.1.2.3/26")
+	first, last = NetworkRange(network)
+	if !first.Equal(net.ParseIP("10.1.2.0")) {
+		t.Error(first.String())
+	}
+	if !last.Equal(net.ParseIP("10.1.2.63")) {
+		t.Error(last.String())
+	}
+}