add NewReplyFromRenew and NewReplyFromRebind (#72)

2 files changed, 102 insertions, 0 deletions

diff --git a/dhcpv6/dhcpv6_test.go b/dhcpv6/dhcpv6_test.go
index ff89280..9f37def 100644
--- a/dhcpv6/dhcpv6_test.go
+++ b/dhcpv6/dhcpv6_test.go
@@ -116,5 +116,39 @@ func TestNewReplyFromRequest(t *testing.T) {
 	require.Equal(t, rep.Type(), REPLY)
 }
 
+func TestNewReplyFromRenew(t *testing.T) {
+	ren := DHCPv6Message{}
+	ren.SetMessage(RENEW)
+	ren.SetTransactionID(0xabcdef)
+	cid := OptClientId{}
+	ren.AddOption(&cid)
+
+	rep, err := NewReplyFromRenew(&ren)
+	require.Error(t, err)
+
+	sid := OptServerId{}
+	ren.AddOption(&sid)
+	rep, err = NewReplyFromRenew(&ren)
+	require.Equal(t, rep.(*DHCPv6Message).TransactionID(), ren.TransactionID())
+	require.Equal(t, rep.Type(), REPLY)
+}
+
+func TestNewReplyFromRebind(t *testing.T) {
+	reb := DHCPv6Message{}
+	reb.SetMessage(REPLY)
+	rep, err := NewReplyFromRebind(&reb)
+	require.Error(t, err)
+
+	reb.SetMessage(REBIND)
+	reb.SetTransactionID(0xabcdef)
+	cid := OptClientId{}
+	reb.AddOption(&cid)
+
+	rep, err = NewReplyFromRebind(&reb)
+	require.NoError(t, err)
+	require.Equal(t, rep.(*DHCPv6Message).TransactionID(), reb.TransactionID())
+	require.Equal(t, rep.Type(), REPLY)
+}
+
 // TODO test NewSolicit
 //      test String and Summary
diff --git a/dhcpv6/dhcpv6message.go b/dhcpv6/dhcpv6message.go
index ab014b3..7c22642 100644
--- a/dhcpv6/dhcpv6message.go
+++ b/dhcpv6/dhcpv6message.go
@@ -198,6 +198,74 @@ func NewRequestFromAdvertise(advertise DHCPv6, modifiers ...Modifier) (DHCPv6, e
 	return d, nil
 }
 
+// NewReplyFromRebind creates a new REPLY packet based on a REBIND packet.
+func NewReplyFromRebind(rebind DHCPv6, modifiers ...Modifier) (DHCPv6, error) {
+	if rebind == nil {
+		return nil, errors.New("REBIND cannot be nil")
+	}
+	if rebind.Type() != REBIND {
+		return nil, errors.New("The passed REBIND must have REBIND type set")
+	}
+	reb, ok := rebind.(*DHCPv6Message)
+	if !ok {
+		return nil, errors.New("The passed REBIND must be of DHCPv6Message type")
+	}
+	// build REPLY from REBIND
+	rep := DHCPv6Message{}
+	rep.SetMessage(REPLY)
+	rep.SetTransactionID(reb.TransactionID())
+	// add Client ID
+	cid := reb.GetOneOption(OPTION_CLIENTID)
+	if cid == nil {
+		return nil, errors.New("Client ID cannot be nil in REBIND when building REPLY")
+	}
+	rep.AddOption(cid)
+
+	// apply modifiers
+	d := DHCPv6(&rep)
+	for _, mod := range modifiers {
+		d = mod(d)
+	}
+	return d, nil
+}
+
+// NewReplyFromRenew creates a new REPLY packet based on a RENEW packet.
+func NewReplyFromRenew(renew DHCPv6, modifiers ...Modifier) (DHCPv6, error) {
+	if renew == nil {
+		return nil, errors.New("RENEW cannot be nil")
+	}
+	if renew.Type() != RENEW {
+		return nil, errors.New("The passed RENEW must have RENEW type set")
+	}
+	ren, ok := renew.(*DHCPv6Message)
+	if !ok {
+		return nil, errors.New("The passed RENEW must be of DHCPv6Message type")
+	}
+	// build REPLY from RENEW
+	rep := DHCPv6Message{}
+	rep.SetMessage(REPLY)
+	rep.SetTransactionID(ren.TransactionID())
+	// add Client ID
+	cid := ren.GetOneOption(OPTION_CLIENTID)
+	if cid == nil {
+		return nil, errors.New("Client ID cannot be nil in RENEW when building REPLY")
+	}
+	rep.AddOption(cid)
+	// add Server ID
+	sid := ren.GetOneOption(OPTION_SERVERID)
+	if sid == nil {
+		return nil, errors.New("Server ID cannot be nil in RENEW when building REPLY")
+	}
+	rep.AddOption(sid)
+
+	// apply modifiers
+	d := DHCPv6(&rep)
+	for _, mod := range modifiers {
+		d = mod(d)
+	}
+	return d, nil
+}
+
 // NewReplyFromRequest creates a new REPLY packet based on a REQUEST packet.
 func NewReplyFromRequest(request DHCPv6, modifiers ...Modifier) (DHCPv6, error) {
 	if request == nil {