diff --git a/protocols/bgp/packet/decode_options.go b/protocols/bgp/packet/decode_options.go
index 9cea580caaccdd2c2176bae4ab5081f281a6f729..fc50c946ed8027f74e6b0ada18eb54387eccd33e 100644
--- a/protocols/bgp/packet/decode_options.go
+++ b/protocols/bgp/packet/decode_options.go
@@ -1,5 +1,7 @@
package packet
+// DecodeOptions represents options for the BGP message decoder
type DecodeOptions struct {
+ AddPath bool
Use32BitASN bool
}
diff --git a/protocols/bgp/packet/decoder.go b/protocols/bgp/packet/decoder.go
index a6f226e49150210b4e3b781a30c571d18b191048..736137582bf1d73f5b474297cdaaf3c6cd8ba167 100644
--- a/protocols/bgp/packet/decoder.go
+++ b/protocols/bgp/packet/decoder.go
@@ -49,7 +49,7 @@ func decodeUpdateMsg(buf *bytes.Buffer, l uint16, opt *DecodeOptions) (*BGPUpdat
return msg, err
}
- msg.WithdrawnRoutes, err = decodeNLRIs(buf, uint16(msg.WithdrawnRoutesLen), IPv4AFI)
+ msg.WithdrawnRoutes, err = decodeNLRIs(buf, uint16(msg.WithdrawnRoutesLen), IPv4AFI, opt.AddPath)
if err != nil {
return msg, err
}
@@ -66,7 +66,7 @@ func decodeUpdateMsg(buf *bytes.Buffer, l uint16, opt *DecodeOptions) (*BGPUpdat
nlriLen := uint16(l) - 4 - uint16(msg.TotalPathAttrLen) - uint16(msg.WithdrawnRoutesLen)
if nlriLen > 0 {
- msg.NLRI, err = decodeNLRIs(buf, nlriLen, IPv4AFI)
+ msg.NLRI, err = decodeNLRIs(buf, nlriLen, IPv4AFI, opt.AddPath)
if err != nil {
return msg, err
}
diff --git a/protocols/bgp/packet/mp_reach_nlri.go b/protocols/bgp/packet/mp_reach_nlri.go
index 513bf5d40265adcca1e00e4186752139eddcd126..e83482e5865dcf0b0084a0aa056c838ae075ed78 100644
--- a/protocols/bgp/packet/mp_reach_nlri.go
+++ b/protocols/bgp/packet/mp_reach_nlri.go
@@ -40,7 +40,7 @@ func (n *MultiProtocolReachNLRI) serialize(buf *bytes.Buffer, opt *EncodeOptions
return uint16(tempBuf.Len())
}
-func deserializeMultiProtocolReachNLRI(b []byte) (MultiProtocolReachNLRI, error) {
+func deserializeMultiProtocolReachNLRI(b []byte, addPath bool) (MultiProtocolReachNLRI, error) {
n := MultiProtocolReachNLRI{}
nextHopLength := uint8(0)
@@ -80,7 +80,7 @@ func deserializeMultiProtocolReachNLRI(b []byte) (MultiProtocolReachNLRI, error)
variable = variable[1+nextHopLength:] // 1 <- RESERVED field
buf := bytes.NewBuffer(variable)
- nlri, err := decodeNLRIs(buf, uint16(buf.Len()), n.AFI)
+ nlri, err := decodeNLRIs(buf, uint16(buf.Len()), n.AFI, addPath)
if err != nil {
return MultiProtocolReachNLRI{}, err
}
diff --git a/protocols/bgp/packet/nlri.go b/protocols/bgp/packet/nlri.go
index 9406c776d2dcadd66f96a4bd71220a6466d2ce31..b5878b56fbe94354811ef0b685d153af9b4b6c0c 100644
--- a/protocols/bgp/packet/nlri.go
+++ b/protocols/bgp/packet/nlri.go
@@ -6,16 +6,22 @@ import (
"math"
bnet "github.com/bio-routing/bio-rd/net"
+ "github.com/bio-routing/bio-rd/util/decode"
"github.com/taktv6/tflow2/convert"
)
+const (
+ pathIdentifierLen = 4
+)
+
+// NLRI represents a Network Layer Reachability Information
type NLRI struct {
PathIdentifier uint32
Prefix bnet.Prefix
Next *NLRI
}
-func decodeNLRIs(buf *bytes.Buffer, length uint16, afi uint16) (*NLRI, error) {
+func decodeNLRIs(buf *bytes.Buffer, length uint16, afi uint16, addPath bool) (*NLRI, error) {
var ret *NLRI
var eol *NLRI
var nlri *NLRI
@@ -24,7 +30,7 @@ func decodeNLRIs(buf *bytes.Buffer, length uint16, afi uint16) (*NLRI, error) {
p := uint16(0)
for p < length {
- nlri, consumed, err = decodeNLRI(buf, afi)
+ nlri, consumed, err = decodeNLRI(buf, afi, addPath)
if err != nil {
return nil, fmt.Errorf("Unable to decode NLRI: %v", err)
}
@@ -43,10 +49,22 @@ func decodeNLRIs(buf *bytes.Buffer, length uint16, afi uint16) (*NLRI, error) {
return ret, nil
}
-func decodeNLRI(buf *bytes.Buffer, afi uint16) (*NLRI, uint8, error) {
+func decodeNLRI(buf *bytes.Buffer, afi uint16, addPath bool) (*NLRI, uint8, error) {
nlri := &NLRI{}
consumed := uint8(0)
+
+ if addPath {
+ err := decode.Decode(buf, []interface{}{
+ &nlri.PathIdentifier,
+ })
+ if err != nil {
+ return nil, consumed, fmt.Errorf("Unable to decode path identifier: %v", err)
+ }
+
+ consumed += pathIdentifierLen
+ }
+
pfxLen, err := buf.ReadByte()
if err != nil {
return nil, consumed, err
diff --git a/protocols/bgp/packet/nlri_test.go b/protocols/bgp/packet/nlri_test.go
index bd4f6653c5e18b905abdb67b0d4ac176b6677a16..ddbc8d85ae8a61d1a0c10c6243f98b22cea98443 100644
--- a/protocols/bgp/packet/nlri_test.go
+++ b/protocols/bgp/packet/nlri_test.go
@@ -46,7 +46,7 @@ func TestDecodeNLRIs(t *testing.T) {
for _, test := range tests {
buf := bytes.NewBuffer(test.input)
- res, err := decodeNLRIs(buf, uint16(len(test.input)), IPv4AFI)
+ res, err := decodeNLRIs(buf, uint16(len(test.input)), IPv4AFI, false)
if test.wantFail && err == nil {
t.Errorf("Expected error did not happen for test %q", test.name)
@@ -64,6 +64,7 @@ func TestDecodeNLRI(t *testing.T) {
tests := []struct {
name string
input []byte
+ addPath bool
wantFail bool
expected *NLRI
}{
@@ -101,6 +102,56 @@ func TestDecodeNLRI(t *testing.T) {
},
wantFail: true,
},
+
+ {
+ name: "Valid NRLI #1 add path",
+ input: []byte{
+ 0, 0, 0, 10, 24, 192, 168, 0,
+ },
+ addPath: true,
+ wantFail: false,
+ expected: &NLRI{
+ PathIdentifier: 10,
+ Prefix: bnet.NewPfx(bnet.IPv4FromOctets(192, 168, 0, 0), 24),
+ },
+ },
+ {
+ name: "Valid NRLI #2 add path",
+ input: []byte{
+ 0, 0, 1, 0, 25, 192, 168, 0, 128,
+ },
+ addPath: true,
+ wantFail: false,
+ expected: &NLRI{
+ PathIdentifier: 256,
+ Prefix: bnet.NewPfx(bnet.IPv4FromOctets(192, 168, 0, 128), 25),
+ },
+ },
+ {
+ name: "Incomplete path Identifier",
+ input: []byte{
+ 0, 0, 0,
+ },
+ addPath: true,
+ wantFail: true,
+ },
+ {
+ name: "Incomplete NLRI #1 add path",
+ input: []byte{
+ 0, 0, 1, 0, 25, 192, 168, 0,
+ },
+ addPath: true,
+ wantFail: true,
+ },
+ {
+ name: "Incomplete NLRI #2 add path",
+ input: []byte{
+ 0, 0, 1, 0, 25,
+ },
+ addPath: true,
+ wantFail: true,
+ },
+
{
name: "Empty input",
input: []byte{},
@@ -110,7 +161,7 @@ func TestDecodeNLRI(t *testing.T) {
for _, test := range tests {
buf := bytes.NewBuffer(test.input)
- res, _, err := decodeNLRI(buf, IPv4AFI)
+ res, _, err := decodeNLRI(buf, IPv4AFI, test.addPath)
if test.wantFail && err == nil {
t.Errorf("Expected error did not happen for test %q", test.name)
diff --git a/protocols/bgp/packet/path_attributes.go b/protocols/bgp/packet/path_attributes.go
index ae81d961753c15059925ef26711c5cc99234ff23..f162e277801410660406c187d9216400fe294fa3 100644
--- a/protocols/bgp/packet/path_attributes.go
+++ b/protocols/bgp/packet/path_attributes.go
@@ -110,7 +110,7 @@ func decodePathAttr(buf *bytes.Buffer, opt *DecodeOptions) (pa *PathAttribute, c
return nil, consumed, fmt.Errorf("Failed to decode OriginatorID: %v", err)
}
case MultiProtocolReachNLRICode:
- if err := pa.decodeMultiProtocolReachNLRI(buf); err != nil {
+ if err := pa.decodeMultiProtocolReachNLRI(buf, opt.AddPath); err != nil {
return nil, consumed, fmt.Errorf("Failed to multi protocol reachable NLRI: %v", err)
}
case MultiProtocolUnreachNLRICode:
@@ -134,7 +134,7 @@ func decodePathAttr(buf *bytes.Buffer, opt *DecodeOptions) (pa *PathAttribute, c
return pa, consumed + pa.Length, nil
}
-func (pa *PathAttribute) decodeMultiProtocolReachNLRI(buf *bytes.Buffer) error {
+func (pa *PathAttribute) decodeMultiProtocolReachNLRI(buf *bytes.Buffer, addPath bool) error {
b := make([]byte, pa.Length)
n, err := buf.Read(b)
if err != nil {
@@ -144,7 +144,7 @@ func (pa *PathAttribute) decodeMultiProtocolReachNLRI(buf *bytes.Buffer) error {
return fmt.Errorf("Unable to read %d bytes from buffer, only got %d bytes", pa.Length, n)
}
- nlri, err := deserializeMultiProtocolReachNLRI(b)
+ nlri, err := deserializeMultiProtocolReachNLRI(b, addPath)
if err != nil {
return fmt.Errorf("Unable to decode MP_REACH_NLRI: %v", err)
}
diff --git a/protocols/bgp/packet/path_attributes_test.go b/protocols/bgp/packet/path_attributes_test.go
index 2ddc92834c5592ab5ac30d5274712a389f543be4..1513fecf0352ad76f1bbafa6e29c75385d1bbf80 100644
--- a/protocols/bgp/packet/path_attributes_test.go
+++ b/protocols/bgp/packet/path_attributes_test.go
@@ -903,6 +903,7 @@ func TestDecodeMultiProtocolReachNLRI(t *testing.T) {
tests := []struct {
name string
input []byte
+ addPath bool
wantFail bool
explicitLength uint16
expected *PathAttribute
@@ -992,7 +993,7 @@ func TestDecodeMultiProtocolReachNLRI(t *testing.T) {
pa := &PathAttribute{
Length: l,
}
- err := pa.decodeMultiProtocolReachNLRI(bytes.NewBuffer(test.input))
+ err := pa.decodeMultiProtocolReachNLRI(bytes.NewBuffer(test.input), test.addPath)
if test.wantFail {
if err != nil {