4 files changed, 57 insertions, 24 deletions

diff --git a/dhcpv4/options.go b/dhcpv4/options.go
index d869b7d..02fa6e4 100644
--- a/dhcpv4/options.go
+++ b/dhcpv4/options.go
@@ -126,6 +126,9 @@ func OptionsFromBytesWithoutMagicCookie(data []byte) ([]Option, error) {
 			return nil, err
 		}
 		options = append(options, opt)
+		if opt.Code() == OptionEnd {
+			break
+		}
 
 		// Options with zero length have no length byte, so here we handle the
 		// ones with nonzero length
diff --git a/dhcpv4/options_test.go b/dhcpv4/options_test.go
index 0268483..899fb2c 100644
--- a/dhcpv4/options_test.go
+++ b/dhcpv4/options_test.go
@@ -167,12 +167,9 @@ func TestOptionsFromBytes(t *testing.T) {
 	}
 	opts, err := OptionsFromBytes(options)
 	require.NoError(t, err)
-	require.Equal(t, 5, len(opts))
+	require.Equal(t, 2, len(opts))
 	require.Equal(t, opts[0].(*OptionGeneric), &OptionGeneric{OptionCode: OptionNameServer, Data: []byte{192, 168, 1, 1}})
 	require.Equal(t, opts[1].(*OptionGeneric), &OptionGeneric{OptionCode: OptionEnd})
-	require.Equal(t, opts[2].(*OptionGeneric), &OptionGeneric{OptionCode: OptionPad})
-	require.Equal(t, opts[3].(*OptionGeneric), &OptionGeneric{OptionCode: OptionPad})
-	require.Equal(t, opts[4].(*OptionGeneric), &OptionGeneric{OptionCode: OptionPad})
 }
 
 func TestOptionsFromBytesZeroLength(t *testing.T) {
diff --git a/dhcpv6/async/client_test.go b/dhcpv6/async/client_test.go
index 8665589..0bc3a87 100644
--- a/dhcpv6/async/client_test.go
+++ b/dhcpv6/async/client_test.go
@@ -1,15 +1,17 @@
 package async
 
 import (
+	"context"
 	"net"
 	"testing"
 	"time"
 
-	"github.com/stretchr/testify/require"
 	"github.com/insomniacslk/dhcp/dhcpv6"
 	"github.com/insomniacslk/dhcp/iana"
+	"github.com/stretchr/testify/require"
 )
 
+const retries = 5
 
 // solicit creates new solicit based on the mac address
 func solicit(input string) (dhcpv6.DHCPv6, error) {
@@ -26,21 +28,39 @@ func solicit(input string) (dhcpv6.DHCPv6, error) {
 	return dhcpv6.NewSolicitWithCID(duid)
 }
 
-// server creates a server which responds with predefined answers
-func serve(t *testing.T, addr *net.UDPAddr, responses ...dhcpv6.DHCPv6) {
+// server creates a server which responds with a predefined response
+func serve(ctx context.Context, addr *net.UDPAddr, response dhcpv6.DHCPv6) error {
 	conn, err := net.ListenUDP("udp6", addr)
-	require.NoError(t, err)
-	defer conn.Close()
-	oobdata := []byte{}
-	buffer := make([]byte, dhcpv6.MaxUDPReceivedPacketSize)
-	for _, packet := range responses {
-		n, _, _, src, err := conn.ReadMsgUDP(buffer, oobdata)
-		require.NoError(t, err)
-		_, err = dhcpv6.FromBytes(buffer[:n])
-		require.NoError(t, err)
-		_, err = conn.WriteTo(packet.ToBytes(), src)
-		require.NoError(t, err)
+	if err != nil {
+		return err
 	}
+	go func() {
+		defer conn.Close()
+		oobdata := []byte{}
+		buffer := make([]byte, dhcpv6.MaxUDPReceivedPacketSize)
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			default:
+				conn.SetReadDeadline(time.Now().Add(1 * time.Second))
+				n, _, _, src, err := conn.ReadMsgUDP(buffer, oobdata)
+				if err != nil {
+					continue
+				}
+				_, err = dhcpv6.FromBytes(buffer[:n])
+				if err != nil {
+					continue
+				}
+				conn.SetWriteDeadline(time.Now().Add(1 * time.Second))
+				_, err = conn.WriteTo(response.ToBytes(), src)
+				if err != nil {
+					continue
+				}
+			}
+		}
+	}()
+	return nil
 }
 
 func TestNewClient(t *testing.T) {
@@ -108,15 +128,26 @@ func TestSend(t *testing.T) {
 	c.LocalAddr = addr
 	c.RemoteAddr = remote
 
-	go serve(t, remote, a)
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	err = serve(ctx, remote, a)
+	require.NoError(t, err)
 
 	err = c.Open(16)
 	require.NoError(t, err)
 	defer c.Close()
 
 	f := c.Send(s)
-	response, err, timeout := f.GetOrTimeout(1000)
-	require.False(t, timeout)
-	require.NoError(t, err)
-	require.Equal(t, a, response)
+
+	var passed bool
+	for i := 0; i < retries; i++ {
+		response, err, timeout := f.GetOrTimeout(1000)
+		if timeout {
+			continue
+		}
+		passed = true
+		require.NoError(t, err)
+		require.Equal(t, a, response)
+	}
+	require.True(t, passed, "All attempts to TestSend timed out")
 }
diff --git a/netboot/netboot.go b/netboot/netboot.go
index 81ba144..2f4cc8f 100644
--- a/netboot/netboot.go
+++ b/netboot/netboot.go
@@ -15,7 +15,6 @@ func RequestNetbootv6(ifname string, timeout time.Duration, retries int, modifie
 	var (
 		conversation []dhcpv6.DHCPv6
 	)
-	modifiers = append(modifiers, dhcpv6.WithNetboot)
 	delay := 2 * time.Second
 	for i := 0; i <= retries; i++ {
 		log.Printf("sending request, attempt #%d", i+1)
@@ -26,6 +25,9 @@ func RequestNetbootv6(ifname string, timeout time.Duration, retries int, modifie
 
 		client := dhcpv6.NewClient()
 		client.ReadTimeout = timeout
+		// WithNetboot is added only later, to avoid applying it twice (one
+		// here and one in the above call to NewSolicitForInterface)
+		modifiers = append(modifiers, dhcpv6.WithNetboot)
 		conversation, err = client.Exchange(ifname, solicit, modifiers...)
 		if err != nil {
 			log.Printf("Client.Exchange failed: %v", err)