Support multiple IP addresses in CNI_ARGS

plugins/ipam/static/README.md

@@ -48,7 +48,7 @@ static IPAM is very simple IPAM plugin that assigns IPv4 and IPv6 addresses stat
 
 The following [CNI_ARGS](https://github.com/containernetworking/cni/blob/master/SPEC.md#parameters) are supported:
 
-* `IP`: request a specific CIDR notation IP address
+* `IP`: request a specific CIDR notation IP addresses, comma separated
 * `GATEWAY`: request a specific gateway address
 
     (example: CNI_ARGS="IP=10.10.0.1/24;GATEWAY=10.10.0.254")

plugins/ipam/static/main.go

@@ -18,6 +18,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net"
+	"strings"
 
 	"github.com/containernetworking/cni/pkg/skel"
 	"github.com/containernetworking/cni/pkg/types"
@@ -46,7 +47,7 @@ type IPAMConfig struct {
 type IPAMEnvArgs struct {
 	types.CommonArgs
 	IP      types.UnmarshallableString `json:"ip,omitempty"`
-	GATEWAY net.IP                     `json:"gateway,omitempty"`
+	GATEWAY types.UnmarshallableString `json:"gateway,omitempty"`
 }
 
 type Address struct {
@@ -124,23 +125,39 @@ func LoadIPAMConfig(bytes []byte, envArgs string) (*IPAMConfig, string, error) {
 		}
 
 		if e.IP != "" {
-			ip, subnet, err := net.ParseCIDR(string(e.IP))
-			if err != nil {
-				return nil, "", fmt.Errorf("invalid CIDR %s: %s", e.IP, err)
-			}
+			for _, item := range strings.Split(string(e.IP), ",") {
+				ipstr := strings.TrimSpace(item)
 
-			addr := Address{Address: net.IPNet{IP: ip, Mask: subnet.Mask}}
-			if e.GATEWAY != nil {
-				addr.Gateway = e.GATEWAY
+				ip, subnet, err := net.ParseCIDR(ipstr)
+				if err != nil {
+					return nil, "", fmt.Errorf("invalid CIDR %s: %s", e.IP, err)
+				}
+
+				addr := Address{Address: net.IPNet{IP: ip, Mask: subnet.Mask}}
+				if addr.Address.IP.To4() != nil {
+					addr.Version = "4"
+					numV4++
+				} else {
+					addr.Version = "6"
+					numV6++
+				}
+				n.IPAM.Addresses = append(n.IPAM.Addresses, addr)
 			}
-			if addr.Address.IP.To4() != nil {
-				addr.Version = "4"
-				numV4++
-			} else {
-				addr.Version = "6"
-				numV6++
+		}
+
+		if e.GATEWAY != "" {
+			for _, item := range strings.Split(string(e.GATEWAY), ",") {
+				gwip := net.ParseIP(strings.TrimSpace(item))
+				if gwip == nil {
+					return nil, "", fmt.Errorf("invalid gateway address: %s", item)
+				}
+
+				for i := range n.IPAM.Addresses {
+					if n.IPAM.Addresses[i].Address.Contains(gwip) {
+						n.IPAM.Addresses[i].Gateway = gwip
+					}
+				}
 			}
-			n.IPAM.Addresses = append(n.IPAM.Addresses, addr)
 		}
 	}
 

plugins/ipam/static/static_test.go

@@ -210,6 +210,61 @@ var _ = Describe("static Operations", func() {
 		})
 		Expect(err).NotTo(HaveOccurred())
 	})
+
+	It("allocates and releases multiple addresses with ADD/DEL, with ENV variables", func() {
+		const ifname string = "eth0"
+		const nspath string = "/some/where"
+
+		conf := `{
+			"cniVersion": "0.3.1",
+			"name": "mynet",
+			"type": "ipvlan",
+			"master": "foo0",
+			"ipam": {
+				"type": "static"
+			}
+		}`
+
+		args := &skel.CmdArgs{
+			ContainerID: "dummy",
+			Netns:       nspath,
+			IfName:      ifname,
+			StdinData:   []byte(conf),
+			Args:        "IP=10.10.0.1/24,11.11.0.1/24;GATEWAY=10.10.0.254",
+		}
+
+		// Allocate the IP
+		r, raw, err := testutils.CmdAddWithArgs(args, func() error {
+			return cmdAdd(args)
+		})
+		Expect(err).NotTo(HaveOccurred())
+		Expect(strings.Index(string(raw), "\"version\":")).Should(BeNumerically(">", 0))
+
+		result, err := current.GetResult(r)
+		Expect(err).NotTo(HaveOccurred())
+
+		// Gomega is cranky about slices with different caps
+		Expect(*result.IPs[0]).To(Equal(
+			current.IPConfig{
+				Version: "4",
+				Address: mustCIDR("10.10.0.1/24"),
+				Gateway: net.ParseIP("10.10.0.254"),
+			}))
+		Expect(*result.IPs[1]).To(Equal(
+			current.IPConfig{
+				Version: "4",
+				Address: mustCIDR("11.11.0.1/24"),
+				Gateway: nil,
+			}))
+
+		Expect(len(result.IPs)).To(Equal(2))
+
+		// Release the IP
+		err = testutils.CmdDelWithArgs(args, func() error {
+			return cmdDel(args)
+		})
+		Expect(err).NotTo(HaveOccurred())
+	})
 })
 
 func mustCIDR(s string) net.IPNet {