host-local: add ifname to file tracking IP address used

plugins/ipam/host-local/backend/allocator/allocator.go

@@ -41,7 +41,7 @@ func NewIPAllocator(s *RangeSet, store backend.Store, id int) *IPAllocator {
 }
 
 // Get alocates an IP
-func (a *IPAllocator) Get(id string, requestedIP net.IP) (*current.IPConfig, error) {
+func (a *IPAllocator) Get(id string, ifname string, requestedIP net.IP) (*current.IPConfig, error) {
 	a.store.Lock()
 	defer a.store.Unlock()
 
@@ -62,7 +62,7 @@ func (a *IPAllocator) Get(id string, requestedIP net.IP) (*current.IPConfig, err
 			return nil, fmt.Errorf("requested ip %s is subnet's gateway", requestedIP.String())
 		}
 
-		reserved, err := a.store.Reserve(id, requestedIP, a.rangeID)
+		reserved, err := a.store.Reserve(id, ifname, requestedIP, a.rangeID)
 		if err != nil {
 			return nil, err
 		}
@@ -83,7 +83,7 @@ func (a *IPAllocator) Get(id string, requestedIP net.IP) (*current.IPConfig, err
 				break
 			}
 
-			reserved, err := a.store.Reserve(id, reservedIP.IP, a.rangeID)
+			reserved, err := a.store.Reserve(id, ifname, reservedIP.IP, a.rangeID)
 			if err != nil {
 				return nil, err
 			}
@@ -110,11 +110,11 @@ func (a *IPAllocator) Get(id string, requestedIP net.IP) (*current.IPConfig, err
 }
 
 // Release clears all IPs allocated for the container with given ID
-func (a *IPAllocator) Release(id string) error {
+func (a *IPAllocator) Release(id string, ifname string) error {
 	a.store.Lock()
 	defer a.store.Unlock()
 
-	return a.store.ReleaseByID(id)
+	return a.store.ReleaseByID(id, ifname)
 }
 
 type RangeIter struct {

plugins/ipam/host-local/backend/allocator/allocator_test.go

@@ -70,7 +70,7 @@ func (t AllocatorTestCase) run(idx int) (*current.IPConfig, error) {
 		rangeID:  "rangeid",
 	}
 
-	return alloc.Get("ID", nil)
+	return alloc.Get("ID", "eth0", nil)
 }
 
 var _ = Describe("host-local ip allocator", func() {
@@ -88,8 +88,8 @@ var _ = Describe("host-local ip allocator", func() {
 
 		It("should loop correctly from the end", func() {
 			a := mkalloc()
-			a.store.Reserve("ID", net.IP{192, 168, 1, 6}, a.rangeID)
-			a.store.ReleaseByID("ID")
+			a.store.Reserve("ID", "eth0", net.IP{192, 168, 1, 6}, a.rangeID)
+			a.store.ReleaseByID("ID", "eth0")
 			r, _ := a.GetIter()
 			Expect(r.nextip()).To(Equal(net.IP{192, 168, 1, 2}))
 			Expect(r.nextip()).To(Equal(net.IP{192, 168, 1, 3}))
@@ -100,8 +100,8 @@ var _ = Describe("host-local ip allocator", func() {
 		})
 		It("should loop correctly from the middle", func() {
 			a := mkalloc()
-			a.store.Reserve("ID", net.IP{192, 168, 1, 3}, a.rangeID)
-			a.store.ReleaseByID("ID")
+			a.store.Reserve("ID", "eth0", net.IP{192, 168, 1, 3}, a.rangeID)
+			a.store.ReleaseByID("ID", "eth0")
 			r, _ := a.GetIter()
 			Expect(r.nextip()).To(Equal(net.IP{192, 168, 1, 4}))
 			Expect(r.nextip()).To(Equal(net.IP{192, 168, 1, 5}))
@@ -221,28 +221,28 @@ var _ = Describe("host-local ip allocator", func() {
 		It("should not allocate the broadcast address", func() {
 			alloc := mkalloc()
 			for i := 2; i < 7; i++ {
-				res, err := alloc.Get("ID", nil)
+				res, err := alloc.Get("ID", "eth0", nil)
 				Expect(err).ToNot(HaveOccurred())
 				s := fmt.Sprintf("192.168.1.%d/29", i)
 				Expect(s).To(Equal(res.Address.String()))
 				fmt.Fprintln(GinkgoWriter, "got ip", res.Address.String())
 			}
 
-			x, err := alloc.Get("ID", nil)
+			x, err := alloc.Get("ID", "eth0", nil)
 			fmt.Fprintln(GinkgoWriter, "got ip", x)
 			Expect(err).To(HaveOccurred())
 		})
 
 		It("should allocate in a round-robin fashion", func() {
 			alloc := mkalloc()
-			res, err := alloc.Get("ID", nil)
+			res, err := alloc.Get("ID", "eth0", nil)
 			Expect(err).ToNot(HaveOccurred())
 			Expect(res.Address.String()).To(Equal("192.168.1.2/29"))
 
-			err = alloc.Release("ID")
+			err = alloc.Release("ID", "eth0")
 			Expect(err).ToNot(HaveOccurred())
 
-			res, err = alloc.Get("ID", nil)
+			res, err = alloc.Get("ID", "eth0", nil)
 			Expect(err).ToNot(HaveOccurred())
 			Expect(res.Address.String()).To(Equal("192.168.1.3/29"))
 
@@ -252,35 +252,35 @@ var _ = Describe("host-local ip allocator", func() {
 			It("must allocate the requested IP", func() {
 				alloc := mkalloc()
 				requestedIP := net.IP{192, 168, 1, 5}
-				res, err := alloc.Get("ID", requestedIP)
+				res, err := alloc.Get("ID", "eth0", requestedIP)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(res.Address.IP.String()).To(Equal(requestedIP.String()))
 			})
 
 			It("must fail when the requested IP is allocated", func() {
 				alloc := mkalloc()
 				requestedIP := net.IP{192, 168, 1, 5}
-				res, err := alloc.Get("ID", requestedIP)
+				res, err := alloc.Get("ID", "eth0", requestedIP)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(res.Address.IP.String()).To(Equal(requestedIP.String()))
 
-				_, err = alloc.Get("ID", requestedIP)
+				_, err = alloc.Get("ID", "eth0", requestedIP)
 				Expect(err).To(MatchError(`requested IP address 192.168.1.5 is not available in range set 192.168.1.1-192.168.1.6`))
 			})
 
 			It("must return an error when the requested IP is after RangeEnd", func() {
 				alloc := mkalloc()
 				(*alloc.rangeset)[0].RangeEnd = net.IP{192, 168, 1, 4}
 				requestedIP := net.IP{192, 168, 1, 5}
-				_, err := alloc.Get("ID", requestedIP)
+				_, err := alloc.Get("ID", "eth0", requestedIP)
 				Expect(err).To(HaveOccurred())
 			})
 
 			It("must return an error when the requested IP is before RangeStart", func() {
 				alloc := mkalloc()
 				(*alloc.rangeset)[0].RangeStart = net.IP{192, 168, 1, 3}
 				requestedIP := net.IP{192, 168, 1, 2}
-				_, err := alloc.Get("ID", requestedIP)
+				_, err := alloc.Get("ID", "eth0", requestedIP)
 				Expect(err).To(HaveOccurred())
 			})
 		})

plugins/ipam/host-local/backend/disk/backend.go

@@ -26,6 +26,7 @@ import (
 )
 
 const lastIPFilePrefix = "last_reserved_ip."
+const LineBreak = "\r\n"
 
 var defaultDataDir = "/var/lib/cni/networks"
 
@@ -55,7 +56,7 @@ func New(network, dataDir string) (*Store, error) {
 	return &Store{lk, dir}, nil
 }
 
-func (s *Store) Reserve(id string, ip net.IP, rangeID string) (bool, error) {
+func (s *Store) Reserve(id string, ifname string, ip net.IP, rangeID string) (bool, error) {
 	fname := GetEscapedPath(s.dataDir, ip.String())
 
 	f, err := os.OpenFile(fname, os.O_RDWR|os.O_EXCL|os.O_CREATE, 0644)
@@ -65,7 +66,7 @@ func (s *Store) Reserve(id string, ip net.IP, rangeID string) (bool, error) {
 	if err != nil {
 		return false, err
 	}
-	if _, err := f.WriteString(strings.TrimSpace(id)); err != nil {
+	if _, err := f.WriteString(strings.TrimSpace(id) + LineBreak + ifname); err != nil {
 		f.Close()
 		os.Remove(f.Name())
 		return false, err
@@ -97,9 +98,8 @@ func (s *Store) Release(ip net.IP) error {
 	return os.Remove(GetEscapedPath(s.dataDir, ip.String()))
 }
 
-// N.B. This function eats errors to be tolerant and
-// release as much as possible
-func (s *Store) ReleaseByID(id string) error {
+func (s *Store) ReleaseByKey(id string, ifname string, match string) (bool, error) {
+	found := false
 	err := filepath.Walk(s.dataDir, func(path string, info os.FileInfo, err error) error {
 		if err != nil || info.IsDir() {
 			return nil
@@ -108,13 +108,30 @@ func (s *Store) ReleaseByID(id string) error {
 		if err != nil {
 			return nil
 		}
-		if strings.TrimSpace(string(data)) == strings.TrimSpace(id) {
+		if strings.TrimSpace(string(data)) == match {
 			if err := os.Remove(path); err != nil {
 				return nil
 			}
+			found = true
 		}
 		return nil
 	})
+	return found, err
+
+}
+
+// N.B. This function eats errors to be tolerant and
+// release as much as possible
+func (s *Store) ReleaseByID(id string, ifname string) error {
+	found := false
+	match := strings.TrimSpace(id) + LineBreak + ifname
+	found, err := s.ReleaseByKey(id, ifname, match)
+
+	// For backwards compatibility, look for files written by a previous version
+	if !found && err == nil {
+		match := strings.TrimSpace(id)
+		found, err = s.ReleaseByKey(id, ifname, match)
+	}
 	return err
 }
 

plugins/ipam/host-local/backend/store.go

@@ -20,8 +20,8 @@ type Store interface {
 	Lock() error
 	Unlock() error
 	Close() error
-	Reserve(id string, ip net.IP, rangeID string) (bool, error)
+	Reserve(id string, ifname string, ip net.IP, rangeID string) (bool, error)
 	LastReservedIP(rangeID string) (net.IP, error)
 	Release(ip net.IP) error
-	ReleaseByID(id string) error
+	ReleaseByID(id string, ifname string) error
 }

plugins/ipam/host-local/backend/testing/fake_store.go

@@ -45,7 +45,7 @@ func (s *FakeStore) Close() error {
 	return nil
 }
 
-func (s *FakeStore) Reserve(id string, ip net.IP, rangeID string) (bool, error) {
+func (s *FakeStore) Reserve(id string, ifname string, ip net.IP, rangeID string) (bool, error) {
 	key := ip.String()
 	if _, ok := s.ipMap[key]; !ok {
 		s.ipMap[key] = id
@@ -68,7 +68,7 @@ func (s *FakeStore) Release(ip net.IP) error {
 	return nil
 }
 
-func (s *FakeStore) ReleaseByID(id string) error {
+func (s *FakeStore) ReleaseByID(id string, ifname string) error {
 	toDelete := []string{}
 	for k, v := range s.ipMap {
 		if v == id {