added cidr validation and made hook execs to command array with args

go.mod

@@ -16,6 +16,8 @@ require (
 	github.com/google/uuid v1.1.2 // indirect
 	github.com/hashicorp/go-hclog v0.15.0
 	github.com/hashicorp/raft v1.2.0
+	github.com/mdlayher/arp v0.0.0-20191213142603-f72070a231fc
+	github.com/mdlayher/ethernet v0.0.0-20190606142754-0394541c37b7
 	github.com/vishvananda/netlink v1.1.0
 	go.etcd.io/etcd v3.3.25+incompatible
 	go.uber.org/zap v1.16.0

go.sum

@@ -82,6 +82,14 @@ github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hd
 github.com/mattn/go-isatty v0.0.10 h1:qxFzApOv4WsAL965uUPIsXzAKCZxN2p9UqdhFS4ZW10=
 github.com/mattn/go-isatty v0.0.10/go.mod h1:qgIWMr58cqv1PHHyhnkY9lrL7etaEgOFcMEpPG5Rm84=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
+github.com/mdlayher/arp v0.0.0-20191213142603-f72070a231fc h1:m7rJJJeXrYCFpsxXYapkDW53wJCDmf9bsIXUg0HoeQY=
+github.com/mdlayher/arp v0.0.0-20191213142603-f72070a231fc/go.mod h1:eOj1DDj3NAZ6yv+WafaKzY37MFZ58TdfIhQ+8nQbiis=
+github.com/mdlayher/ethernet v0.0.0-20190313224307-5b5fc417d966/go.mod h1:5s5p/sMJ6sNsFl6uCh85lkFGV8kLuIYJCRJLavVJwvg=
+github.com/mdlayher/ethernet v0.0.0-20190606142754-0394541c37b7 h1:lez6TS6aAau+8wXUP3G9I3TGlmPFEq2CTxBaRqY6AGE=
+github.com/mdlayher/ethernet v0.0.0-20190606142754-0394541c37b7/go.mod h1:U6ZQobyTjI/tJyq2HG+i/dfSoFUt8/aZCM+GKtmFk/Y=
+github.com/mdlayher/raw v0.0.0-20190313224157-43dbcdd7739d/go.mod h1:r1fbeITl2xL/zLbVnNHFyOzQJTgr/3fpf1lJX/cjzR8=
+github.com/mdlayher/raw v0.0.0-20190606142536-fef19f00fc18 h1:zwOa3e/13D6veNIz6zzuqrd3eZEMF0dzD0AQWKcYSs4=
+github.com/mdlayher/raw v0.0.0-20190606142536-fef19f00fc18/go.mod h1:7EpbotpCmVZcu+KCX4g9WaRNuu11uyhiW7+Le1dKawg=
 github.com/pascaldekloe/goe v0.1.0/go.mod h1:lzWF7FIEvWOWxwDKqyGYQf6ZUaNfKdP144TG7ZOy1lc=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
@@ -125,7 +133,10 @@ golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73r
 golang.org/x/net v0.0.0-20181201002055-351d144fa1fc/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190213061140-3a22650c66bd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190313220215-9f648a60d977/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190419010253-1f3472d942ba/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190603091049-60506f45cf65/go.mod h1:HSz+uSET+XFnRR8LxR5pz3Of3rY3CfYBVs4xY44aLks=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859 h1:R/3boaszxrf1GEUWTVDzSKVwLmSJpwZ1yqXm8j0v2QI=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
@@ -135,8 +146,11 @@ golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190312061237-fead79001313/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190418153312-f0ce4c0180be/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190523142557-0e01d883c5c5/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190606122018-79a91cf218c4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190606203320-7fc4e5ec1444/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191008105621-543471e840be/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200202164722-d101bd2416d5 h1:LfCXLvNmTYH9kEmVgqbnsWfruoXZIrh4YBgqVHtDvw0=

pkg/config/config.go

@@ -7,6 +7,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/vishvananda/netlink"
 	"gopkg.in/yaml.v2"
 )
 
@@ -41,14 +42,20 @@ func Validate(c *Config) error {
 	if len(c.VirtualIPs) == 0 {
 		return errors.New("missing virtualIPs config")
 	}
-	if c.LeaderHook != "" {
+	for _, vip := range c.VirtualIPs {
-		if !filepath.IsAbs(c.LeaderHook) {
+		_, err := netlink.ParseAddr(vip)
-			return errors.New("leaderHook path must be absolute")
+		if err != nil {
+			return fmt.Errorf("failed to parse CIDR virtualIP '%s': %w", vip, err)
 		}
 	}
-	if c.FollowerHook != "" {
+	if len(c.LeaderHook) > 0 {
-		if !filepath.IsAbs(c.FollowerHook) {
+		if !filepath.IsAbs(c.LeaderHook[0]) {
-			return errors.New("followerHook path must be absolute")
+			return errors.New("leaderHook executable path must be absolute")
+		}
+	}
+	if len(c.FollowerHook) > 0 {
+		if !filepath.IsAbs(c.FollowerHook[0]) {
+			return errors.New("followerHook executable path must be absolute")
 		}
 	}
 	raft := c.Cluster.Raft
@@ -116,8 +123,8 @@ type Config struct {
 	VirtualIPs   []string `yaml:"virtualIPs"`
 	Interface    string   `yaml:"interface,omitempty"`
 	Label        string   `yaml:"label,omitempty"`
-	LeaderHook   string   `yaml:"leaderHook,omitempty"`
+	LeaderHook   []string `yaml:"leaderHook,omitempty"`
-	FollowerHook string   `yaml:"followerHook,omitempty"`
+	FollowerHook []string `yaml:"followerHook,omitempty"`
 	Cluster      Cluster  `yaml:"cluster"`
 }
 

pkg/controller/vip.go

@@ -19,9 +19,9 @@ func NewVIPController(cfg *config.Config) (callbacks cluster.Callbacks, err erro
 	callbacks = cluster.Callbacks{
 		Leader: func(ctx context.Context, cc cluster.CallbackContext) {
 			t := time.NewTicker(time.Second * 10)
-			if cfg.LeaderHook != "" {
+			if len(cfg.LeaderHook) > 0 {
 				go func() {
-					err := exec.CommandContext(ctx, cfg.LeaderHook).Run()
+					err := exec.CommandContext(ctx, cfg.LeaderHook[0], cfg.LeaderHook[1:]...).Run()
 					if err != nil {
 						cc.Error(err, "error running hook", "leaderHook", cfg.LeaderHook)
 					}
@@ -42,9 +42,9 @@ func NewVIPController(cfg *config.Config) (callbacks cluster.Callbacks, err erro
 		},
 		Follower: func(ctx context.Context, cc cluster.CallbackContext) {
 			t := time.NewTicker(time.Second * 10)
-			if cfg.FollowerHook != "" {
+			if len(cfg.FollowerHook) > 0 {
 				go func() {
-					err := exec.CommandContext(ctx, cfg.FollowerHook).Run()
+					err := exec.CommandContext(ctx, cfg.FollowerHook[0], cfg.FollowerHook[1:]...).Run()
 					if err != nil {
 						cc.Error(err, "error running hook", "followerHook", cfg.FollowerHook)
 					}
@@ -52,8 +52,7 @@ func NewVIPController(cfg *config.Config) (callbacks cluster.Callbacks, err erro
 			}
 			for {
 				cc.Info("following", "id", cc.ID())
-				//TODO
+				deleteIPs(cc, n, cfg.VirtualIPs)
-				//deleteIPs(cc, n, cfg.VirtualIPs)
 				select {
 				case <-ctx.Done():
 					t.Stop()

pkg/vip/arp_linux.go

@@ -1,159 +1,30 @@
-// +build linux
-
-// These syscalls are only supported on Linux, so this uses a build directive during compilation. Other OS's will use the arp_unsupported.go and receive an error
-
 package vip
 
 import (
-	"bytes"
-	"encoding/binary"
 	"fmt"
 	"net"
-	"syscall"
+
-	"unsafe"
+	"github.com/mdlayher/arp"
+	"github.com/mdlayher/ethernet"
 )
 
-const (
+func sendARP(ip net.IP, iface *net.Interface) error {
-	opARPRequest = 1
+	c, err := arp.Dial(iface)
-	opARPReply   = 2
-	hwLen        = 6
-)
-
-var (
-	ethernetBroadcast = net.HardwareAddr{0xff, 0xff, 0xff, 0xff, 0xff, 0xff}
-	// arpRequest is used to flip between garp request or garp reply
-	arpRequest = true
-)
-
-func htons(p uint16) uint16 {
-	var b [2]byte
-	binary.BigEndian.PutUint16(b[:], p)
-	return *(*uint16)(unsafe.Pointer(&b))
-}
-
-// arpHeader specifies the header for an ARP message.
-type arpHeader struct {
-	hardwareType          uint16
-	protocolType          uint16
-	hardwareAddressLength uint8
-	protocolAddressLength uint8
-	opcode                uint16
-}
-
-// arpMessage represents an ARP message.
-type arpMessage struct {
-	arpHeader
-	senderHardwareAddress []byte
-	senderProtocolAddress []byte
-	targetHardwareAddress []byte
-	targetProtocolAddress []byte
-}
-
-// bytes returns the wire representation of the ARP message.
-func (m *arpMessage) bytes() ([]byte, error) {
-	buf := new(bytes.Buffer)
-
-	if err := binary.Write(buf, binary.BigEndian, m.arpHeader); err != nil {
-		return nil, fmt.Errorf("binary write failed: %v", err)
-	}
-	buf.Write(m.senderHardwareAddress)
-	buf.Write(m.senderProtocolAddress)
-	buf.Write(m.targetHardwareAddress)
-	buf.Write(m.targetProtocolAddress)
-
-	return buf.Bytes(), nil
-}
-
-// gratuitousARP return a gARP request or gARP reply alternatively
-// because different devices may support either one of them
-func gratuitousARP(ip net.IP, mac net.HardwareAddr) (*arpMessage, error) {
-	if ip.To4() == nil {
-		return nil, fmt.Errorf("%q is not an IPv4 address", ip)
-	}
-	if len(mac) != hwLen {
-		return nil, fmt.Errorf("%q is not an Ethernet MAC address", mac)
-	}
-
-	m := &arpMessage{
-		arpHeader: arpHeader{
-			1,           // Ethernet
-			0x0800,      // IPv4
-			hwLen,       // 48-bit MAC Address
-			net.IPv4len, // 32-bit IPv4 Address
-			opARPReply,  // ARP Reply
-		},
-	}
-
-	// https://tools.ietf.org/html/rfc5944#section-4.6
-	// In either case, the ARP Sender Hardware Address is
-	// set to the link-layer address to which this cache entry should be
-	// updated.
-	m.senderHardwareAddress = mac
-
-	// When using an ARP Reply packet, the Target Hardware
-	// Address is also set to the link-layer address to which this cache
-	// entry should be updated (this field is not used in an ARP Request
-	// packet).
-	m.targetHardwareAddress = mac
-
-	// In either case, the ARP Sender Protocol Address and
-	// ARP Target Protocol Address are both set to the IP address of the
-	// cache entry to be updated,
-	m.senderProtocolAddress = ip.To4()
-	m.targetProtocolAddress = ip.To4()
-
-	// send arpRequest and arpReply alternatively
-	arpRequest = !arpRequest
-	if arpRequest {
-		m.arpHeader.opcode = opARPRequest
-
-		// this field is not used in an ARP Request packet
-		m.targetHardwareAddress = ethernetBroadcast
-	}
-
-	return m, nil
-}
-
-// sendARP sends the given ARP message via the specified interface.
-func sendARP(iface *net.Interface, m *arpMessage) error {
-	fd, err := syscall.Socket(syscall.AF_PACKET, syscall.SOCK_DGRAM, int(htons(syscall.ETH_P_ARP)))
 	if err != nil {
-		return fmt.Errorf("failed to get raw socket: %v", err)
+		return err
 	}
-	defer syscall.Close(fd)
+	for _, op := range []arp.Operation{arp.OperationRequest, arp.OperationReply} {
-
+		pkt, err := arp.NewPacket(op, iface.HardwareAddr, ip, ethernet.Broadcast, ip)
-	if err := syscall.BindToDevice(fd, iface.Name); err != nil {
+		if err != nil {
-		return fmt.Errorf("failed to bind to device: %v", err)
+			return fmt.Errorf("assembling %q gratuitous packet for %q: %s", op, ip, err)
+		}
+		if err = c.WriteTo(pkt, ethernet.Broadcast); err != nil {
+			return fmt.Errorf("writing %q gratuitous packet for %q: %s", op, ip, err)
+		}
 	}
-
-	ll := syscall.SockaddrLinklayer{
-		Protocol: htons(syscall.ETH_P_ARP),
-		Ifindex:  iface.Index,
-		Pkttype:  0, // syscall.PACKET_HOST
-		Hatype:   m.hardwareType,
-		Halen:    m.hardwareAddressLength,
-	}
-	target := ethernetBroadcast
-	for i := 0; i < len(target); i++ {
-		ll.Addr[i] = target[i]
-	}
-
-	b, err := m.bytes()
-	if err != nil {
-		return fmt.Errorf("failed to convert ARP message: %v", err)
-	}
-
-	if err := syscall.Bind(fd, &ll); err != nil {
-		return fmt.Errorf("failed to bind: %v", err)
-	}
-	if err := syscall.Sendto(fd, b, 0, &ll); err != nil {
-		return fmt.Errorf("failed to send: %v", err)
-	}
-
 	return nil
 }
 
-// ARPSendGratuitous sends a gratuitous ARP message via the specified interface.
 func ARPSendGratuitous(cidr, iface string) error {
 	i, err := net.InterfaceByName(iface)
 	if err != nil {
@@ -163,11 +34,5 @@ func ARPSendGratuitous(cidr, iface string) error {
 	if err != nil {
 		return fmt.Errorf("failed to parse cidr: %s", cidr)
 	}
-
+	return sendARP(ip, i)
-	//log.Infof("Broadcasting ARP update for %s (%s) via %s", address, iface.HardwareAddr, iface.Name)
-	m, err := gratuitousARP(ip, i.HardwareAddr)
-	if err != nil {
-		return err
-	}
-	return sendARP(i, m)
 }

vipman.yaml

@@ -2,8 +2,10 @@ virtualIPs:
 - ""
 interface: ""
 label: ""
-leaderHook: ""
+leaderHook:
-followerHook: ""
+- ""
+followerHook:
+- ""
 cluster:
   raft:
     dir: ""