nclient6: small fixes

- RapidCommit solicits wait for Reply messages, not Advertise.
- Default recipient should be all relay agents and servers, not just
  servers.
- Make New() and NewWithConn() interface same as in nclient4.

Signed-off-by: Christopher Koch <chrisko@google.com>

3 files changed, 40 insertions, 12 deletions

diff --git a/dhcpv6/nclient6/client.go b/dhcpv6/nclient6/client.go
index dc5dd33..8b338db 100644
--- a/dhcpv6/nclient6/client.go
+++ b/dhcpv6/nclient6/client.go
@@ -90,15 +90,30 @@ func NewIPv6UDPConn(iface string, port int) (net.PacketConn, error) {
 	})
 }
 
-// New creates a new DHCP client that sends and receives packets on the given
-// interface.
-func New(ifaceHWAddr net.HardwareAddr, opts ...ClientOpt) (*Client, error) {
+// New returns a new DHCPv6 client for the given network interface.
+func New(iface string, opts ...ClientOpt) (*Client, error) {
+	c, err := NewIPv6UDPConn(iface, dhcpv6.DefaultClientPort)
+	if err != nil {
+		return nil, err
+	}
+
+	i, err := net.InterfaceByName(iface)
+	if err != nil {
+		return nil, err
+	}
+	return NewWithConn(c, i.HardwareAddr, opts...)
+}
+
+// NewWithConn creates a new DHCP client that sends and receives packets on the
+// given interface.
+func NewWithConn(conn net.PacketConn, ifaceHWAddr net.HardwareAddr, opts ...ClientOpt) (*Client, error) {
 	c := &Client{
 		ifaceHWAddr: ifaceHWAddr,
 		timeout:     5 * time.Second,
 		retry:       3,
-		serverAddr:  AllDHCPServers,
+		serverAddr:  AllDHCPRelayAgentsAndServers,
 		bufferCap:   5,
+		conn:        conn,
 
 		done:    make(chan struct{}),
 		pending: make(map[dhcpv6.TransactionID]*pendingCh),
@@ -239,6 +254,20 @@ func IsMessageType(t dhcpv6.MessageType) Matcher {
 	}
 }
 
+// RapidSolicit sends a solicitation message with the RapidCommit option and
+// returns the first valid reply received.
+func (c *Client) RapidSolicit(ctx context.Context, modifiers ...dhcpv6.Modifier) (*dhcpv6.Message, error) {
+	solicit, err := dhcpv6.NewSolicit(c.ifaceHWAddr, append(modifiers, dhcpv6.WithRapidCommit)...)
+	if err != nil {
+		return nil, err
+	}
+	msg, err := c.SendAndRead(ctx, c.serverAddr, solicit, IsMessageType(dhcpv6.MessageTypeReply))
+	if err != nil {
+		return nil, err
+	}
+	return msg, nil
+}
+
 // Solicit sends a solicitation message and returns the first valid
 // advertisement received.
 func (c *Client) Solicit(ctx context.Context, modifiers ...dhcpv6.Modifier) (*dhcpv6.Message, error) {
diff --git a/dhcpv6/nclient6/client_test.go b/dhcpv6/nclient6/client_test.go
index cba4ef8..49b914e 100644
--- a/dhcpv6/nclient6/client_test.go
+++ b/dhcpv6/nclient6/client_test.go
@@ -55,9 +55,9 @@ func serveAndClient(ctx context.Context, responses [][]*dhcpv6.Message, opt ...C
 		panic(err)
 	}
 
-	o := []ClientOpt{WithConn(clientRawConn), WithRetry(1), WithTimeout(2 * time.Second)}
+	o := []ClientOpt{WithRetry(1), WithTimeout(2 * time.Second)}
 	o = append(o, opt...)
-	mc, err := New(net.HardwareAddr{0xa, 0xb, 0xc, 0xd, 0xe, 0xf}, o...)
+	mc, err := NewWithConn(clientRawConn, net.HardwareAddr{0xa, 0xb, 0xc, 0xd, 0xe, 0xf}, o...)
 	if err != nil {
 		panic(err)
 	}
diff --git a/dhcpv6/server6/server_test.go b/dhcpv6/server6/server_test.go
index 05d62cb..3b204f1 100644
--- a/dhcpv6/server6/server_test.go
+++ b/dhcpv6/server6/server_test.go
@@ -12,15 +12,16 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-type fakeUnconnectedConn struct {
+// Turns a connected UDP conn into an "unconnected" UDP conn.
+type unconnectedConn struct {
 	*net.UDPConn
 }
 
-func (f fakeUnconnectedConn) WriteTo(b []byte, _ net.Addr) (int, error) {
+func (f unconnectedConn) WriteTo(b []byte, _ net.Addr) (int, error) {
 	return f.UDPConn.Write(b)
 }
 
-func (f fakeUnconnectedConn) ReadFrom(b []byte) (int, net.Addr, error) {
+func (f unconnectedConn) ReadFrom(b []byte) (int, net.Addr, error) {
 	n, err := f.Read(b)
 	return n, nil, err
 }
@@ -43,12 +44,10 @@ func setUpClientAndServer(handler Handler) (*nclient6.Client, *Server) {
 		panic(err)
 	}
 
-	c, err := nclient6.New(net.HardwareAddr{1, 2, 3, 4, 5, 6},
-		nclient6.WithConn(fakeUnconnectedConn{clientConn}))
+	c, err := nclient6.NewWithConn(unconnectedConn{clientConn}, net.HardwareAddr{1, 2, 3, 4, 5, 6})
 	if err != nil {
 		panic(err)
 	}
-
 	return c, s
 }