table: fix merging of v4 paths with addpath enabled

V4 NLRI needs more 4 bytes with addpath enabled.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

3 files changed, 32 insertions, 29 deletions

diff --git a/packet/bgp/bgp.go b/packet/bgp/bgp.go
index 49a276b1..ef31817c 100644
--- a/packet/bgp/bgp.go
+++ b/packet/bgp/bgp.go
@@ -33,7 +33,7 @@ type MarshallingOption struct {
 	AddPath map[RouteFamily]BGPAddPathMode
 }
 
-func handleAddPath(decode bool, f RouteFamily, options []*MarshallingOption) bool {
+func IsAddPathEnabled(decode bool, f RouteFamily, options []*MarshallingOption) bool {
 	for _, opt := range options {
 		if opt == nil {
 			continue
@@ -1102,7 +1102,7 @@ func (r *IPAddrPrefix) DecodeFromBytes(data []byte, options ...*MarshallingOptio
 	if r.addrlen == 16 {
 		f = RF_IPv6_UC
 	}
-	if handleAddPath(true, f, options) {
+	if IsAddPathEnabled(true, f, options) {
 		var err error
 		data, err = r.decodePathIdentifier(data)
 		if err != nil {
@@ -1124,7 +1124,7 @@ func (r *IPAddrPrefix) Serialize(options ...*MarshallingOption) ([]byte, error)
 		f = RF_IPv6_UC
 	}
 	var buf []byte
-	if handleAddPath(false, f, options) {
+	if IsAddPathEnabled(false, f, options) {
 		var err error
 		buf, err = r.serializeIdentifier()
 		if err != nil {
@@ -1564,7 +1564,7 @@ func (l *LabeledVPNIPAddrPrefix) DecodeFromBytes(data []byte, options ...*Marsha
 	if l.addrlen == 16 {
 		f = RF_IPv6_VPN
 	}
-	if handleAddPath(true, f, options) {
+	if IsAddPathEnabled(true, f, options) {
 		var err error
 		data, err = l.decodePathIdentifier(data)
 		if err != nil {
@@ -1593,7 +1593,7 @@ func (l *LabeledVPNIPAddrPrefix) Serialize(options ...*MarshallingOption) ([]byt
 		f = RF_IPv6_VPN
 	}
 	var buf []byte
-	if handleAddPath(false, f, options) {
+	if IsAddPathEnabled(false, f, options) {
 		var err error
 		buf, err = l.serializeIdentifier()
 		if err != nil {
@@ -1711,7 +1711,7 @@ func (l *LabeledIPAddrPrefix) DecodeFromBytes(data []byte, options ...*Marshalli
 	if l.addrlen == 16 {
 		f = RF_IPv6_MPLS
 	}
-	if handleAddPath(true, f, options) {
+	if IsAddPathEnabled(true, f, options) {
 		var err error
 		data, err = l.decodePathIdentifier(data)
 		if err != nil {
@@ -1736,7 +1736,7 @@ func (l *LabeledIPAddrPrefix) Serialize(options ...*MarshallingOption) ([]byte,
 		f = RF_IPv6_MPLS
 	}
 	var buf []byte
-	if handleAddPath(false, f, options) {
+	if IsAddPathEnabled(false, f, options) {
 		var err error
 		buf, err = l.serializeIdentifier()
 		if err != nil {
@@ -1816,7 +1816,7 @@ type RouteTargetMembershipNLRI struct {
 }
 
 func (n *RouteTargetMembershipNLRI) DecodeFromBytes(data []byte, options ...*MarshallingOption) error {
-	if handleAddPath(true, RF_RTC_UC, options) {
+	if IsAddPathEnabled(true, RF_RTC_UC, options) {
 		var err error
 		data, err = n.decodePathIdentifier(data)
 		if err != nil {
@@ -1844,7 +1844,7 @@ func (n *RouteTargetMembershipNLRI) DecodeFromBytes(data []byte, options ...*Mar
 
 func (n *RouteTargetMembershipNLRI) Serialize(options ...*MarshallingOption) ([]byte, error) {
 	var buf []byte
-	if handleAddPath(false, RF_RTC_UC, options) {
+	if IsAddPathEnabled(false, RF_RTC_UC, options) {
 		var err error
 		buf, err = n.serializeIdentifier()
 		if err != nil {
@@ -2684,7 +2684,7 @@ type EVPNNLRI struct {
 }
 
 func (n *EVPNNLRI) DecodeFromBytes(data []byte, options ...*MarshallingOption) error {
-	if handleAddPath(true, RF_EVPN, options) {
+	if IsAddPathEnabled(true, RF_EVPN, options) {
 		var err error
 		data, err = n.decodePathIdentifier(data)
 		if err != nil {
@@ -2710,7 +2710,7 @@ func (n *EVPNNLRI) DecodeFromBytes(data []byte, options ...*MarshallingOption) e
 
 func (n *EVPNNLRI) Serialize(options ...*MarshallingOption) ([]byte, error) {
 	var buf []byte
-	if handleAddPath(false, RF_EVPN, options) {
+	if IsAddPathEnabled(false, RF_EVPN, options) {
 		var err error
 		buf, err = n.serializeIdentifier()
 		if err != nil {
@@ -2783,7 +2783,7 @@ func (n *EncapNLRI) DecodeFromBytes(data []byte, options ...*MarshallingOption)
 	if n.addrlen == 16 {
 		f = RF_IPv6_ENCAP
 	}
-	if handleAddPath(true, f, options) {
+	if IsAddPathEnabled(true, f, options) {
 		var err error
 		data, err = n.decodePathIdentifier(data)
 		if err != nil {
@@ -2808,7 +2808,7 @@ func (n *EncapNLRI) Serialize(options ...*MarshallingOption) ([]byte, error) {
 	if n.addrlen == 16 {
 		f = RF_IPv6_ENCAP
 	}
-	if handleAddPath(false, f, options) {
+	if IsAddPathEnabled(false, f, options) {
 		var err error
 		buf, err = n.serializeIdentifier()
 		if err != nil {
@@ -3940,7 +3940,7 @@ func (n *FlowSpecNLRI) RD() RouteDistinguisherInterface {
 }
 
 func (n *FlowSpecNLRI) decodeFromBytes(rf RouteFamily, data []byte, options ...*MarshallingOption) error {
-	if handleAddPath(true, rf, options) {
+	if IsAddPathEnabled(true, rf, options) {
 		var err error
 		data, err = n.decodePathIdentifier(data)
 		if err != nil {
@@ -4062,7 +4062,7 @@ func (n *FlowSpecNLRI) Serialize(options ...*MarshallingOption) ([]byte, error)
 		buf = append(b, buf...)
 	}
 
-	if handleAddPath(false, n.rf, options) {
+	if IsAddPathEnabled(false, n.rf, options) {
 		id, err := n.serializeIdentifier()
 		if err != nil {
 			return nil, err
@@ -4319,7 +4319,7 @@ func (n *OpaqueNLRI) DecodeFromBytes(data []byte, options ...*MarshallingOption)
 	if len(data) < 2 {
 		return NewMessageError(BGP_ERROR_UPDATE_MESSAGE_ERROR, BGP_ERROR_SUB_MALFORMED_ATTRIBUTE_LIST, nil, "Not all OpaqueNLRI bytes available")
 	}
-	if handleAddPath(true, RF_OPAQUE, options) {
+	if IsAddPathEnabled(true, RF_OPAQUE, options) {
 		var err error
 		data, err = n.decodePathIdentifier(data)
 		if err != nil {
@@ -4343,7 +4343,7 @@ func (n *OpaqueNLRI) Serialize(options ...*MarshallingOption) ([]byte, error) {
 	binary.BigEndian.PutUint16(buf, uint16(len(n.Key)))
 	buf = append(buf, n.Key...)
 	buf = append(buf, n.Value...)
-	if handleAddPath(false, RF_OPAQUE, options) {
+	if IsAddPathEnabled(false, RF_OPAQUE, options) {
 		id, err := n.serializeIdentifier()
 		if err != nil {
 			return nil, err
@@ -5811,7 +5811,7 @@ func (p *PathAttributeMpReachNLRI) DecodeFromBytes(data []byte, options ...*Mars
 	}
 	value = value[1:]
 	addpathLen := 0
-	if handleAddPath(true, AfiSafiToRouteFamily(afi, safi), options) {
+	if IsAddPathEnabled(true, AfiSafiToRouteFamily(afi, safi), options) {
 		addpathLen = 4
 	}
 	for len(value) > 0 {
@@ -5957,7 +5957,7 @@ func (p *PathAttributeMpUnreachNLRI) DecodeFromBytes(data []byte, options ...*Ma
 	p.AFI = afi
 	p.SAFI = safi
 	addpathLen := 0
-	if handleAddPath(true, AfiSafiToRouteFamily(afi, safi), options) {
+	if IsAddPathEnabled(true, AfiSafiToRouteFamily(afi, safi), options) {
 		addpathLen = 4
 	}
 	for len(value) > 0 {
@@ -8109,7 +8109,7 @@ func (msg *BGPUpdate) DecodeFromBytes(data []byte, options ...*MarshallingOption
 	}
 
 	addpathLen := 0
-	if handleAddPath(true, RF_IPv4_UC, options) {
+	if IsAddPathEnabled(true, RF_IPv4_UC, options) {
 		addpathLen = 4
 	}
 
diff --git a/server/fsm.go b/server/fsm.go
index aaa13922..556e1029 100644
--- a/server/fsm.go
+++ b/server/fsm.go
@@ -1445,7 +1445,7 @@ func (h *FSMHandler) sendMessageloop() error {
 			return nil
 		case o := <-h.outgoing.Out():
 			m := o.(*FsmOutgoingMsg)
-			for _, msg := range table.CreateUpdateMsgFromPaths(m.Paths) {
+			for _, msg := range table.CreateUpdateMsgFromPaths(m.Paths, h.fsm.marshallingOptions) {
 				if err := send(msg); err != nil {
 					return nil
 				}
diff --git a/table/message.go b/table/message.go
index 4f49e36f..0e4acc7d 100644
--- a/table/message.go
+++ b/table/message.go
@@ -270,7 +270,7 @@ func newCage(b []byte, path *Path) *cage {
 
 type packerInterface interface {
 	add(*Path)
-	pack() []*bgp.BGPMessage
+	pack(options ...*bgp.MarshallingOption) []*bgp.BGPMessage
 }
 
 type packer struct {
@@ -314,7 +314,7 @@ func createMPReachMessage(path *Path) *bgp.BGPMessage {
 	return bgp.NewBGPUpdateMessage(nil, attrs, nil)
 }
 
-func (p *packerMP) pack() []*bgp.BGPMessage {
+func (p *packerMP) pack(options ...*bgp.MarshallingOption) []*bgp.BGPMessage {
 	msgs := make([]*bgp.BGPMessage, 0, p.packer.total)
 
 	for _, path := range p.withdrawals {
@@ -392,7 +392,7 @@ func (p *packerV4) add(path *Path) {
 	}
 }
 
-func (p *packerV4) pack() []*bgp.BGPMessage {
+func (p *packerV4) pack(options ...*bgp.MarshallingOption) []*bgp.BGPMessage {
 	split := func(max int, paths []*Path) ([]*bgp.IPAddrPrefix, []*Path) {
 		nlris := make([]*bgp.IPAddrPrefix, 0, max)
 		i := 0
@@ -404,12 +404,15 @@ func (p *packerV4) pack() []*bgp.BGPMessage {
 		}
 		return nlris, paths[i:]
 	}
+	addpathNLRILen := 0
+	if bgp.IsAddPathEnabled(false, p.packer.family, options) {
+		addpathNLRILen = 4
+	}
 	// Header + Update (WithdrawnRoutesLen +
 	// TotalPathAttributeLen + attributes + maxlen of NLRI).
-	// the max size of NLRI is 5bytes
-	// TODO: addpath needs 4 bytes per NLRI
+	// the max size of NLRI is 5bytes (plus 4bytes with addpath enabled)
 	maxNLRIs := func(attrsLen int) int {
-		return (bgp.BGP_MAX_MESSAGE_LENGTH - (19 + 2 + 2 + attrsLen)) / 5
+		return (bgp.BGP_MAX_MESSAGE_LENGTH - (19 + 2 + 2 + attrsLen)) / (5 + addpathNLRILen)
 	}
 
 	loop := func(attrsLen int, paths []*Path, cb func([]*bgp.IPAddrPrefix)) {
@@ -476,7 +479,7 @@ func newPacker(f bgp.RouteFamily) packerInterface {
 	}
 }
 
-func CreateUpdateMsgFromPaths(pathList []*Path) []*bgp.BGPMessage {
+func CreateUpdateMsgFromPaths(pathList []*Path, options ...*bgp.MarshallingOption) []*bgp.BGPMessage {
 	msgs := make([]*bgp.BGPMessage, 0, len(pathList))
 
 	m := make(map[bgp.RouteFamily]packerInterface)
@@ -489,7 +492,7 @@ func CreateUpdateMsgFromPaths(pathList []*Path) []*bgp.BGPMessage {
 	}
 
 	for _, p := range m {
-		msgs = append(msgs, p.pack()...)
+		msgs = append(msgs, p.pack(options...)...)
 	}
 	return msgs
 }