Add support for multiple subnets and gateways per network

Author: ofiliz

cni/network/network.go

@@ -84,7 +84,7 @@ func (plugin *netPlugin) Stop() {
 
 // GetEndpointID returns a unique endpoint ID based on the CNI args.
 func (plugin *netPlugin) getEndpointID(args *cniSkel.CmdArgs) string {
-	return args.ContainerID + "-" + args.IfName
+	return args.ContainerID[:8] + "-" + args.IfName
 }
 
 //
@@ -115,7 +115,7 @@ func (plugin *netPlugin) Add(args *cniSkel.CmdArgs) error {
 	nwInfo, err := plugin.nm.GetNetworkInfo(networkId)
 	if err != nil {
 		// Network does not exist.
-		log.Printf("[cni-net] Creating network.")
+		log.Printf("[cni-net] Creating network %v.", networkId)
 
 		// Call into IPAM plugin to allocate an address pool for the network.
 		result, err = cniInvoke.DelegateAdd(nwCfg.Ipam.Type, nwCfg.Serialize())
@@ -127,21 +127,27 @@ func (plugin *netPlugin) Add(args *cniSkel.CmdArgs) error {
 
 		log.Printf("[cni-net] IPAM plugin returned result %v.", resultImpl)
 
-		// Derive the subnet from allocated IP address.
-		subnet := resultImpl.IP4.IP
-		subnet.IP = subnet.IP.Mask(subnet.Mask)
+		// Derive the subnet prefix from allocated IP address.
+		subnetPrefix := resultImpl.IP4.IP
+		subnetPrefix.IP = subnetPrefix.IP.Mask(subnetPrefix.Mask)
 
 		// Add the master as an external interface.
-		err = plugin.nm.AddExternalInterface(nwCfg.Master, subnet.String())
+		err = plugin.nm.AddExternalInterface(nwCfg.Master, subnetPrefix.String())
 		if err != nil {
 			return plugin.Errorf("Failed to add external interface: %v", err)
 		}
 
 		// Create the network.
 		nwInfo := network.NetworkInfo{
-			Id:         networkId,
-			Mode:       nwCfg.Mode,
-			Subnets:    []string{subnet.String()},
+			Id:   networkId,
+			Mode: nwCfg.Mode,
+			Subnets: []network.SubnetInfo{
+				network.SubnetInfo{
+					Family:  platform.AfINET,
+					Prefix:  subnetPrefix,
+					Gateway: resultImpl.IP4.Gateway,
+				},
+			},
 			BridgeName: nwCfg.Bridge,
 		}
 
@@ -150,13 +156,14 @@ func (plugin *netPlugin) Add(args *cniSkel.CmdArgs) error {
 			return plugin.Errorf("Failed to create network: %v", err)
 		}
 
-		log.Printf("[cni-net] Created network %v with subnet %v.", networkId, subnet.String())
+		log.Printf("[cni-net] Created network %v with subnet %v.", networkId, subnetPrefix.String())
 	} else {
 		// Network already exists.
-		log.Printf("[cni-net] Found network %v with subnet %v.", networkId, nwInfo.Subnets[0])
+		subnetPrefix := nwInfo.Subnets[0].Prefix.String()
+		log.Printf("[cni-net] Found network %v with subnet %v.", networkId, subnetPrefix)
 
 		// Call into IPAM plugin to allocate an address for the endpoint.
-		nwCfg.Ipam.Subnet = nwInfo.Subnets[0]
+		nwCfg.Ipam.Subnet = subnetPrefix
 		result, err = cniInvoke.DelegateAdd(nwCfg.Ipam.Type, nwCfg.Serialize())
 		if err != nil {
 			return plugin.Errorf("Failed to allocate address: %v", err)
@@ -185,11 +192,11 @@ func (plugin *netPlugin) Add(args *cniSkel.CmdArgs) error {
 	}
 
 	// Populate DNS info.
-	epInfo.DNSSuffix = resultImpl.DNS.Domain
-	epInfo.DNSServers = resultImpl.DNS.Nameservers
+	epInfo.DNS.Suffix = resultImpl.DNS.Domain
+	epInfo.DNS.Servers = resultImpl.DNS.Nameservers
 
 	// Create the endpoint.
-	log.Printf("[cni-net] Creating endpoint %+v", epInfo)
+	log.Printf("[cni-net] Creating endpoint %v.", epInfo.Id)
 	err = plugin.nm.CreateEndpoint(networkId, epInfo)
 	if err != nil {
 		return plugin.Errorf("Failed to create endpoint: %v", err)
@@ -245,7 +252,7 @@ func (plugin *netPlugin) Delete(args *cniSkel.CmdArgs) error {
 	}
 
 	// Call into IPAM plugin to release the endpoint's addresses.
-	nwCfg.Ipam.Subnet = nwInfo.Subnets[0]
+	nwCfg.Ipam.Subnet = nwInfo.Subnets[0].Prefix.String()
 	for _, address := range epInfo.IPAddresses {
 		nwCfg.Ipam.Address = address.IP.String()
 		err = cniInvoke.DelegateDel(nwCfg.Ipam.Type, nwCfg.Serialize())

cnm/network/network.go

@@ -11,6 +11,7 @@ import (
 	"github.com/Azure/azure-container-networking/common"
 	"github.com/Azure/azure-container-networking/log"
 	"github.com/Azure/azure-container-networking/network"
+	"github.com/Azure/azure-container-networking/platform"
 )
 
 const (
@@ -138,13 +139,22 @@ func (plugin *netPlugin) createNetwork(w http.ResponseWriter, r *http.Request) {
 		nwInfo.Mode, _ = options[modeOption].(string)
 	}
 
-	// Assume single pool per address family.
-	if len(req.IPv4Data) > 0 {
-		nwInfo.Subnets = append(nwInfo.Subnets, req.IPv4Data[0].Pool)
-	}
-
-	if len(req.IPv6Data) > 0 {
-		nwInfo.Subnets = append(nwInfo.Subnets, req.IPv6Data[0].Pool)
+	// Populate subnets.
+	for _, data := range [][]ipamData{req.IPv4Data, req.IPv6Data} {
+		for _, ipamData := range data {
+			_, prefix, err := net.ParseCIDR(ipamData.Pool)
+			if err != nil {
+				continue
+			}
+
+			subnet := network.SubnetInfo{
+				Family:  platform.GetAddressFamily(&prefix.IP),
+				Prefix:  *prefix,
+				Gateway: net.ParseIP(ipamData.Gateway),
+			}
+
+			nwInfo.Subnets = append(nwInfo.Subnets, subnet)
+		}
 	}
 
 	err = plugin.nm.CreateNetwork(&nwInfo)

network/endpoint.go

@@ -29,8 +29,7 @@ type EndpointInfo struct {
 	IfName      string
 	IPAddresses []net.IPNet
 	Routes      []RouteInfo
-	DNSSuffix   string
-	DNSServers  []string
+	DNS         DNSInfo
 }
 
 // RouteInfo contains information about an IP route.

network/endpoint_windows.go

@@ -20,8 +20,8 @@ func (nw *network) newEndpointImpl(epInfo *EndpointInfo) (*endpoint, error) {
 	hnsEndpoint := &hcsshim.HNSEndpoint{
 		Name:           epInfo.Id,
 		VirtualNetwork: nw.HnsId,
-		DNSSuffix:      epInfo.DNSSuffix,
-		DNSServerList:  strings.Join(epInfo.DNSServers, ","),
+		DNSSuffix:      epInfo.DNS.Suffix,
+		DNSServerList:  strings.Join(epInfo.DNS.Servers, ","),
 	}
 
 	// HNS currently supports only one IP address per endpoint.
@@ -31,18 +31,6 @@ func (nw *network) newEndpointImpl(epInfo *EndpointInfo) (*endpoint, error) {
 		hnsEndpoint.PrefixLength = uint8(pl)
 	}
 
-	// HNS currently supports only one (default) route per endpoint.
-	for _, route := range epInfo.Routes {
-		var pl int
-		if route.Dst.Mask != nil {
-			pl, _ = route.Dst.Mask.Size()
-		}
-		if route.Dst.Mask == nil || pl == 0 {
-			hnsEndpoint.GatewayAddress = route.Gw.String()
-			break
-		}
-	}
-
 	// Marshal the request.
 	buffer, err := json.Marshal(hnsEndpoint)
 	if err != nil {

network/manager.go

@@ -203,7 +203,7 @@ func (nm *networkManager) GetNetworkInfo(networkId string) (*NetworkInfo, error)
 
 	nwInfo := &NetworkInfo{
 		Id:      networkId,
-		Subnets: []string{nw.extIf.Subnets[0]},
+		Subnets: nw.Subnets,
 	}
 
 	return nwInfo, nil

network/network.go

@@ -7,6 +7,7 @@ import (
 	"net"
 
 	"github.com/Azure/azure-container-networking/log"
+	"github.com/Azure/azure-container-networking/platform"
 )
 
 const (
@@ -34,6 +35,7 @@ type network struct {
 	Id        string
 	HnsId     string `json:",omitempty"`
 	Mode      string
+	Subnets   []SubnetInfo
 	Endpoints map[string]*endpoint
 	extIf     *externalInterface
 }
@@ -42,11 +44,25 @@ type network struct {
 type NetworkInfo struct {
 	Id         string
 	Mode       string
-	Subnets    []string
+	Subnets    []SubnetInfo
+	DNS        DNSInfo
 	BridgeName string
 	Options    map[string]interface{}
 }
 
+// SubnetInfo contains subnet information for a container network.
+type SubnetInfo struct {
+	Family  platform.AddressFamily
+	Prefix  net.IPNet
+	Gateway net.IP
+}
+
+// DNSInfo contains DNS information for a container network or endpoint.
+type DNSInfo struct {
+	Suffix  string
+	Servers []string
+}
+
 // NewExternalInterface adds a host interface to the list of available external interfaces.
 func (nm *networkManager) newExternalInterface(ifName string, subnet string) error {
 	// Check whether the external interface is already configured.
@@ -112,7 +128,7 @@ func (nm *networkManager) newNetwork(nwInfo *NetworkInfo) (*network, error) {
 	}
 
 	// Find the external interface for this subnet.
-	extIf := nm.findExternalInterfaceBySubnet(nwInfo.Subnets[0])
+	extIf := nm.findExternalInterfaceBySubnet(nwInfo.Subnets[0].Prefix.String())
 	if extIf == nil {
 		err = errSubnetNotFound
 		goto fail
@@ -131,6 +147,7 @@ func (nm *networkManager) newNetwork(nwInfo *NetworkInfo) (*network, error) {
 	}
 
 	// Add the network object.
+	nw.Subnets = nwInfo.Subnets
 	extIf.Networks[nwInfo.Id] = nw
 
 	log.Printf("[net] Created network %v on interface %v.", nwInfo.Id, extIf.Name)

network/network_windows.go

@@ -42,8 +42,8 @@ func (nm *networkManager) newNetworkImpl(nwInfo *NetworkInfo, extIf *externalInt
 	// Populate subnets.
 	for _, subnet := range nwInfo.Subnets {
 		hnsSubnet := hcsshim.Subnet{
-			AddressPrefix:  subnet,
-			GatewayAddress: extIf.IPv4Gateway.String(),
+			AddressPrefix:  subnet.Prefix.String(),
+			GatewayAddress: subnet.Gateway.String(),
 		}
 
 		hnsNetwork.Subnets = append(hnsNetwork.Subnets, hnsSubnet)
@@ -68,6 +68,7 @@ func (nm *networkManager) newNetworkImpl(nwInfo *NetworkInfo, extIf *externalInt
 	nw := &network{
 		Id:        nwInfo.Id,
 		HnsId:     hnsResponse.Id,
+		Mode:      nwInfo.Mode,
 		Endpoints: make(map[string]*endpoint),
 		extIf:     extIf,
 	}

platform/ip.go

@@ -0,0 +1,30 @@
+// Copyright 2017 Microsoft. All rights reserved.
+// MIT License
+
+package platform
+
+import (
+	"net"
+)
+
+// AddressFamily specifies a protocol address family number.
+type AddressFamily int
+
+const (
+	AfUnspec AddressFamily = 0
+	AfINET   AddressFamily = 0x2
+	AfINET6  AddressFamily = 0xa
+)
+
+// GetAddressFamily returns the address family of an address.
+func GetAddressFamily(address *net.IP) AddressFamily {
+	var family AddressFamily
+
+	if address.To4() == nil {
+		family = AfINET
+	} else {
+		family = AfINET6
+	}
+
+	return family
+}