test: set build constraints for Gont-based tests

Signed-off-by: Steffen Vogel <post@steffenvogel.de>

pkg/device/device_linux_test.go

@@ -0,0 +1,231 @@
+//go:build linux
+
+package device_test
+
+import (
+	"fmt"
+	"math/rand"
+	"net"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+	wgdevice "golang.zx2c4.com/wireguard/device"
+	"riasc.eu/wice/pkg/config"
+	"riasc.eu/wice/pkg/device"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	g "github.com/stv0g/gont/pkg"
+	nl "github.com/vishvananda/netlink"
+)
+
+var _ = Describe("device", func() {
+	var err error
+	var d device.Device
+	var user bool
+	var ns *g.Namespace
+	var nlh *nl.Handle
+	var l nl.Link
+
+	getAddrs := func() []*net.IPNet {
+		addrs, err := nlh.AddrList(l, unix.AF_INET)
+		Expect(err).To(Succeed())
+
+		ips := []*net.IPNet{}
+		for _, addr := range addrs {
+			addr.IP = addr.IP.To16()
+			ips = append(ips, addr.IPNet)
+		}
+
+		return ips
+	}
+
+	JustBeforeEach(OncePerOrdered, func() {
+		name := fmt.Sprintf("wg-test-%d", rand.Intn(1000))
+		ns, err = g.NewNamespace(name)
+		Expect(err).To(Succeed())
+
+		func() {
+			exit, err := ns.Enter()
+			defer exit()
+
+			Expect(err).To(Succeed())
+
+			d, err = device.NewDevice("wg0", user)
+			Expect(err).To(Succeed())
+
+			nlh, err = nl.NewHandleAt(ns.NsHandle)
+			Expect(err).To(Succeed())
+
+			l, err = nlh.LinkByName("wg0")
+			Expect(err).To(Succeed())
+		}()
+	})
+
+	JustAfterEach(OncePerOrdered, func() {
+		func() {
+			exit, err := ns.Enter()
+			Expect(err).To(Succeed())
+
+			defer exit()
+
+			err = d.Close()
+			Expect(err).To(Succeed())
+		}()
+
+		err = ns.Close()
+		Expect(err).To(Succeed())
+	})
+
+	// Overload It() to enter/exit namespace
+	It := func(name string, function func()) {
+		It(name, Offset(1), func() {
+			exit, err := ns.Enter()
+			Expect(err).To(Succeed())
+
+			function()
+			exit()
+		})
+	}
+
+	Test := func() {
+		Context("", Ordered, func() {
+			It("have a matching name", func() {
+				Expect(d.Name()).To(Equal("wg0"))
+			})
+
+			Describe("can manage addresses", Ordered, func() {
+				var addr *net.IPNet
+
+				BeforeAll(func() {
+					addr = &net.IPNet{
+						IP:   net.IPv4(10, 0, 0, 1),
+						Mask: net.IPv4Mask(0xff, 0xff, 0xff, 0xff),
+					}
+				})
+
+				It("can add a new address", func() {
+					err = d.AddAddress(addr)
+					Expect(err).To(Succeed())
+
+					addrs := getAddrs()
+					Expect(addrs).To(ContainElement(addr))
+				})
+
+				It("can delete the address again", func() {
+					err = d.DeleteAddress(addr)
+					Expect(err).To(Succeed())
+
+					addrs := getAddrs()
+					Expect(addrs).To(BeEmpty())
+				})
+			})
+
+			Describe("can manage routes", Ordered, func() {
+				var ip net.IP
+				var route *net.IPNet
+
+				BeforeAll(func() {
+					ip = net.IPv4(10, 0, 0, 1)
+
+					route = &net.IPNet{
+						IP:   net.IPv4(10, 0, 0, 1),
+						Mask: net.IPv4Mask(0xff, 0xff, 0xff, 0xff),
+					}
+				})
+
+				It("can add a new route", func() {
+					// The device must be up before adding device routes
+					err = d.SetUp()
+					Expect(err).To(Succeed())
+
+					err = d.AddRoute(route, config.DefaultRouteTable)
+					Expect(err).To(Succeed())
+
+					routes, err := nl.RouteGet(ip)
+					Expect(err).To(Succeed())
+					Expect(routes).To(HaveLen(1))
+					Expect(routes[0].LinkIndex).To(Equal(d.Index()))
+				})
+
+				It("can delete the route again", func() {
+					err = d.DeleteRoute(route, config.DefaultRouteTable)
+					Expect(err).To(Succeed())
+
+					_, err := nl.RouteGet(ip)
+					Expect(err).To(MatchError(syscall.ENETUNREACH))
+				})
+			})
+
+			Describe("can change link state", Ordered, func() {
+				isUP := func() bool {
+					l, err = nlh.LinkByName("wg0")
+					if err != nil {
+						return false
+					}
+
+					return l.Attrs().Flags&net.FlagUp != 0
+				}
+
+				It("can be brought up", func() {
+					err = d.SetUp()
+					Expect(err).To(Succeed())
+
+					Eventually(isUP).Should(BeTrue())
+				})
+
+				It("can be brought down again", func() {
+					err = d.SetDown()
+					Expect(err).To(Succeed())
+
+					Eventually(isUP).Should(BeFalse())
+				})
+			})
+
+			Describe("can change link attributes", Ordered, func() {
+				It("has the correct interface index", func() {
+					Expect(d.Index()).To(Equal(l.Attrs().Index))
+				})
+
+				It("has the default MTU initially", func() {
+					Expect(d.MTU()).To(Equal(wgdevice.DefaultMTU))
+				})
+
+				It("has the correct MTU", func() {
+					Expect(d.MTU()).To(Equal(l.Attrs().MTU))
+				})
+
+				It("updates the MTU", func() {
+					newMTU := 1300
+
+					err = d.SetMTU(newMTU)
+					Expect(err).To(Succeed())
+
+					Expect(d.MTU()).To(Equal(newMTU))
+
+					// Get updated link attributes
+					l, err = nlh.LinkByName("wg0")
+					Expect(err).To(Succeed())
+
+					Expect(l.Attrs().MTU).To(Equal(newMTU))
+				})
+			})
+		})
+	}
+
+	When("kernel", Ordered, func() {
+		BeforeEach(OncePerOrdered, func() {
+			user = false
+		})
+
+		Test()
+	})
+
+	When("user", func() {
+		BeforeEach(OncePerOrdered, func() {
+			user = true
+		})
+
+		Test()
+	})
+})