diff --git a/protocols/bgp/packet/decoder.go b/protocols/bgp/packet/decoder.go
index e473f3edf38c208f5726ecc3b776dbf883f61197..cafc9b5a21165c5f0b909420335e2fcfe3c62e10 100644
--- a/protocols/bgp/packet/decoder.go
+++ b/protocols/bgp/packet/decoder.go
@@ -9,14 +9,18 @@ import (
"github.com/taktv6/tflow2/convert"
)
+type DecodingOptions struct {
+ Supports4OctetASN bool
+}
+
// Decode decodes a BGP message
-func Decode(buf *bytes.Buffer) (*BGPMessage, error) {
+func Decode(buf *bytes.Buffer, opt *DecodingOptions) (*BGPMessage, error) {
hdr, err := decodeHeader(buf)
if err != nil {
return nil, fmt.Errorf("Failed to decode header: %v", err)
}
- body, err := decodeMsgBody(buf, hdr.Type, hdr.Length-MinLen)
+ body, err := decodeMsgBody(buf, hdr.Type, hdr.Length-MinLen, opt)
if err != nil {
return nil, fmt.Errorf("Failed to decode message: %v", err)
}
@@ -27,12 +31,12 @@ func Decode(buf *bytes.Buffer) (*BGPMessage, error) {
}, nil
}
-func decodeMsgBody(buf *bytes.Buffer, msgType uint8, l uint16) (interface{}, error) {
+func decodeMsgBody(buf *bytes.Buffer, msgType uint8, l uint16, opt *DecodingOptions) (interface{}, error) {
switch msgType {
case OpenMsg:
return decodeOpenMsg(buf)
case UpdateMsg:
- return decodeUpdateMsg(buf, l)
+ return decodeUpdateMsg(buf, l, opt)
case KeepaliveMsg:
return nil, nil // Nothing to decode in Keepalive message
case NotificationMsg:
@@ -41,7 +45,7 @@ func decodeMsgBody(buf *bytes.Buffer, msgType uint8, l uint16) (interface{}, err
return nil, fmt.Errorf("Unknown message type: %d", msgType)
}
-func decodeUpdateMsg(buf *bytes.Buffer, l uint16) (*BGPUpdate, error) {
+func decodeUpdateMsg(buf *bytes.Buffer, l uint16, opt *DecodingOptions) (*BGPUpdate, error) {
msg := &BGPUpdate{}
err := decode(buf, []interface{}{&msg.WithdrawnRoutesLen})
@@ -59,7 +63,7 @@ func decodeUpdateMsg(buf *bytes.Buffer, l uint16) (*BGPUpdate, error) {
return msg, err
}
- msg.PathAttributes, err = decodePathAttrs(buf, msg.TotalPathAttrLen)
+ msg.PathAttributes, err = decodePathAttrs(buf, msg.TotalPathAttrLen, opt)
if err != nil {
return msg, err
}
diff --git a/protocols/bgp/packet/decoder_test.go b/protocols/bgp/packet/decoder_test.go
index 916660a3dd06e08b23d29ea4a8c48fb63ed68b47..a2ad9771d80f102ca8acccd2ff5d6a362160e566 100644
--- a/protocols/bgp/packet/decoder_test.go
+++ b/protocols/bgp/packet/decoder_test.go
@@ -3,6 +3,7 @@ package packet
import (
"bytes"
"fmt"
+ "strconv"
"testing"
"github.com/bio-routing/bio-rd/net"
@@ -70,7 +71,7 @@ func BenchmarkDecodeUpdateMsg(b *testing.B) {
for i := 0; i < b.N; i++ {
buf := bytes.NewBuffer(input)
- _, err := decodeUpdateMsg(buf, uint16(len(input)))
+ _, err := decodeUpdateMsg(buf, uint16(len(input)), &DecodingOptions{})
if err != nil {
fmt.Printf("decodeUpdateMsg failed: %v\n", err)
}
@@ -251,7 +252,7 @@ func TestDecode(t *testing.T) {
for _, test := range tests {
buf := bytes.NewBuffer(test.input)
- msg, err := Decode(buf)
+ msg, err := Decode(buf, &DecodingOptions{})
if err != nil && !test.wantFail {
t.Errorf("Unexpected error in test %d: %v", test.testNum, err)
@@ -1369,9 +1370,9 @@ func TestDecodeUpdateMsg(t *testing.T) {
},
{
// 2 withdraws with four path attributes (Communities + AS4Path +AS4Aggregator + Origin), valid update
- testNum: 19,
+ testNum: 20,
input: []byte{0, 5, 8, 10, 16, 192, 168,
- 0, 30, // Total Path Attribute Length
+ 0, 32, // Total Path Attribute Length
0, // Attribute flags
8, // Attribute Type code (Community)
@@ -1379,10 +1380,12 @@ func TestDecodeUpdateMsg(t *testing.T) {
0, 0, 1, 0, // Arbitrary Community
0, 0, 1, 1, // Arbitrary Community
- 128, // Attribute flags
- 17, // Attribute Type code (AS4Path)
- 4, // Length
- 0, 0, 2, 3, // Arbitrary Bytes
+ 128, // Attribute flags
+ 17, // Attribute Type code (AS4Path)
+ 6, // Length
+ 2, // AS_SEQUENCE
+ 1, // Number of ASNs
+ 0x00, 0x03, 0x17, 0xf3, // 202739
128, // Attribute flags
18, // Attribute Type code (AS4Aggregator)
@@ -1406,7 +1409,7 @@ func TestDecodeUpdateMsg(t *testing.T) {
Pfxlen: 16,
},
},
- TotalPathAttrLen: 30,
+ TotalPathAttrLen: 32,
PathAttributes: &PathAttribute{
Optional: false,
Transitive: false,
@@ -1420,9 +1423,15 @@ func TestDecodeUpdateMsg(t *testing.T) {
Transitive: false,
Partial: false,
ExtendedLength: false,
- Length: 4,
+ Length: 6,
TypeCode: 17,
- Value: uint32(515),
+ Value: ASPath{
+ ASPathSegment{
+ Type: 2,
+ Count: 1,
+ ASNs: []uint32{202739},
+ },
+ },
Next: &PathAttribute{
Optional: true,
Transitive: false,
@@ -1447,29 +1456,31 @@ func TestDecodeUpdateMsg(t *testing.T) {
},
}
+ t.Parallel()
+
for _, test := range tests {
- buf := bytes.NewBuffer(test.input)
- l := test.explicitLength
- if l == 0 {
- l = uint16(len(test.input))
- }
- msg, err := decodeUpdateMsg(buf, l)
+ t.Run(strconv.Itoa(test.testNum), func(t *testing.T) {
+ buf := bytes.NewBuffer(test.input)
+ l := test.explicitLength
+ if l == 0 {
+ l = uint16(len(test.input))
+ }
+ msg, err := decodeUpdateMsg(buf, l, &DecodingOptions{})
- if err != nil && !test.wantFail {
- t.Errorf("Unexpected error in test %d: %v", test.testNum, err)
- continue
- }
+ if err != nil && !test.wantFail {
+ t.Fatalf("Unexpected error in test %d: %v", test.testNum, err)
+ }
- if err == nil && test.wantFail {
- t.Errorf("Expected error did not happen in test %d", test.testNum)
- continue
- }
+ if err == nil && test.wantFail {
+ t.Fatalf("Expected error did not happen in test %d", test.testNum)
+ }
- if err != nil && test.wantFail {
- continue
- }
+ if err != nil && test.wantFail {
+ return
+ }
- assert.Equalf(t, test.expected, msg, "%d", test.testNum)
+ assert.Equalf(t, test.expected, msg, "%d", test.testNum)
+ })
}
}
@@ -1490,7 +1501,7 @@ func TestDecodeMsgBody(t *testing.T) {
}
for _, test := range tests {
- res, err := decodeMsgBody(test.buffer, test.msgType, test.length)
+ res, err := decodeMsgBody(test.buffer, test.msgType, test.length, &DecodingOptions{})
if test.wantFail && err == nil {
t.Errorf("Expected error dit not happen in test %q", test.name)
}
diff --git a/protocols/bgp/packet/encoder_test.go b/protocols/bgp/packet/encoder_test.go
index 0d4f70a3483dabd8f7332dd148c72b09df626dee..fd7405d735a5d11a4117d144e7086828c86f5628 100644
--- a/protocols/bgp/packet/encoder_test.go
+++ b/protocols/bgp/packet/encoder_test.go
@@ -70,7 +70,7 @@ func TestSerializeOpenMsg(t *testing.T) {
name: "Valid #1",
input: &BGPOpen{
Version: 4,
- AS: 15169,
+ ASN: 15169,
HoldTime: 120,
BGPIdentifier: convert.Uint32([]byte{100, 111, 120, 130}),
OptParmLen: 0,
diff --git a/protocols/bgp/packet/path_attributes.go b/protocols/bgp/packet/path_attributes.go
index 3b3192034590bd357b29a13833a2bcaaa632f0cf..d040718eaaf6aae2286938f6a3d97c5a039a7daf 100644
--- a/protocols/bgp/packet/path_attributes.go
+++ b/protocols/bgp/packet/path_attributes.go
@@ -9,7 +9,7 @@ import (
"github.com/taktv6/tflow2/convert"
)
-func decodePathAttrs(buf *bytes.Buffer, tpal uint16) (*PathAttribute, error) {
+func decodePathAttrs(buf *bytes.Buffer, tpal uint16, opt *DecodingOptions) (*PathAttribute, error) {
var ret *PathAttribute
var eol *PathAttribute
var pa *PathAttribute
@@ -18,7 +18,7 @@ func decodePathAttrs(buf *bytes.Buffer, tpal uint16) (*PathAttribute, error) {
p := uint16(0)
for p < tpal {
- pa, consumed, err = decodePathAttr(buf)
+ pa, consumed, err = decodePathAttr(buf, opt)
if err != nil {
return nil, fmt.Errorf("Unable to decode path attr: %v", err)
}
@@ -36,7 +36,7 @@ func decodePathAttrs(buf *bytes.Buffer, tpal uint16) (*PathAttribute, error) {
return ret, nil
}
-func decodePathAttr(buf *bytes.Buffer) (pa *PathAttribute, consumed uint16, err error) {
+func decodePathAttr(buf *bytes.Buffer, opt *DecodingOptions) (pa *PathAttribute, consumed uint16, err error) {
pa = &PathAttribute{}
err = decodePathAttrFlags(buf, pa)
@@ -63,9 +63,18 @@ func decodePathAttr(buf *bytes.Buffer) (pa *PathAttribute, consumed uint16, err
return nil, consumed, fmt.Errorf("Failed to decode Origin: %v", err)
}
case ASPathAttr:
- if err := pa.decodeASPath(buf); err != nil {
+ asnLength := uint8(2)
+ if opt.Supports4OctetASN {
+ asnLength = 4
+ }
+
+ if err := pa.decodeASPath(buf, asnLength); err != nil {
return nil, consumed, fmt.Errorf("Failed to decode AS Path: %v", err)
}
+ case AS4PathAttr:
+ if err := pa.decodeASPath(buf, 4); err != nil {
+ return nil, consumed, fmt.Errorf("Failed to decode AS4 Path: %v", err)
+ }
case NextHopAttr:
if err := pa.decodeNextHop(buf); err != nil {
return nil, consumed, fmt.Errorf("Failed to decode Next-Hop: %v", err)
@@ -88,10 +97,6 @@ func decodePathAttr(buf *bytes.Buffer) (pa *PathAttribute, consumed uint16, err
if err := pa.decodeCommunities(buf); err != nil {
return nil, consumed, fmt.Errorf("Failed to decode Community: %v", err)
}
- case AS4PathAttr:
- if err := pa.decodeAS4Path(buf); err != nil {
- return nil, consumed, fmt.Errorf("Failed to skip not supported AS4Path: %v", err)
- }
case AS4AggregatorAttr:
if err := pa.decodeAS4Aggregator(buf); err != nil {
return nil, consumed, fmt.Errorf("Failed to skip not supported AS4Aggregator: %v", err)
@@ -139,14 +144,11 @@ func (pa *PathAttribute) decodeOrigin(buf *bytes.Buffer) error {
return dumpNBytes(buf, pa.Length-p)
}
-func (pa *PathAttribute) decodeASPath(buf *bytes.Buffer) error {
+func (pa *PathAttribute) decodeASPath(buf *bytes.Buffer, asnLength uint8) error {
pa.Value = make(ASPath, 0)
-
p := uint16(0)
for p < pa.Length {
- segment := ASPathSegment{
- ASNs: make([]uint32, 0),
- }
+ segment := ASPathSegment{}
err := decode(buf, []interface{}{&segment.Type, &segment.Count})
if err != nil {
@@ -162,23 +164,51 @@ func (pa *PathAttribute) decodeASPath(buf *bytes.Buffer) error {
return fmt.Errorf("Invalid AS Path segment length: %d", segment.Count)
}
+ segment.ASNs = make([]uint32, segment.Count)
for i := uint8(0); i < segment.Count; i++ {
- asn := uint16(0)
-
- err := decode(buf, []interface{}{&asn})
+ asn, err := pa.decodeASN(buf, asnLength)
if err != nil {
return err
}
- p += 2
+ p += uint16(asnLength)
- segment.ASNs = append(segment.ASNs, uint32(asn))
+ segment.ASNs[i] = asn
}
+
pa.Value = append(pa.Value.(ASPath), segment)
}
return nil
}
+func (pa *PathAttribute) decodeASN(buf *bytes.Buffer, asnSize uint8) (asn uint32, err error) {
+ if asnSize == 4 {
+ return pa.decode4ByteASN(buf)
+ }
+
+ return pa.decode2ByteASN(buf)
+}
+
+func (pa *PathAttribute) decode4ByteASN(buf *bytes.Buffer) (asn uint32, err error) {
+ asn4 := uint32(0)
+ err = decode(buf, []interface{}{&asn4})
+ if err != nil {
+ return 0, err
+ }
+
+ return uint32(asn4), nil
+}
+
+func (pa *PathAttribute) decode2ByteASN(buf *bytes.Buffer) (asn uint32, err error) {
+ asn4 := uint16(0)
+ err = decode(buf, []interface{}{&asn4})
+ if err != nil {
+ return 0, err
+ }
+
+ return uint32(asn4), nil
+}
+
func (pa *PathAttribute) decodeNextHop(buf *bytes.Buffer) error {
return pa.decodeUint32(buf, "next hop")
}
@@ -273,10 +303,6 @@ func (pa *PathAttribute) decodeLargeCommunities(buf *bytes.Buffer) error {
return nil
}
-func (pa *PathAttribute) decodeAS4Path(buf *bytes.Buffer) error {
- return pa.decodeUint32(buf, "AS4Path")
-}
-
func (pa *PathAttribute) decodeAS4Aggregator(buf *bytes.Buffer) error {
return pa.decodeUint32(buf, "AS4Aggregator")
}
diff --git a/protocols/bgp/packet/path_attributes_test.go b/protocols/bgp/packet/path_attributes_test.go
index 248b731714389096a62e2381a548780beb8318e7..5b816cc49aefe865f9afcebdfbe0e359793e3cbe 100644
--- a/protocols/bgp/packet/path_attributes_test.go
+++ b/protocols/bgp/packet/path_attributes_test.go
@@ -50,7 +50,7 @@ func TestDecodePathAttrs(t *testing.T) {
}
for _, test := range tests {
- res, err := decodePathAttrs(bytes.NewBuffer(test.input), uint16(len(test.input)))
+ res, err := decodePathAttrs(bytes.NewBuffer(test.input), uint16(len(test.input)), &DecodingOptions{})
if test.wantFail && err == nil {
t.Errorf("Expected error did not happen for test %q", test.name)
@@ -173,7 +173,7 @@ func TestDecodePathAttr(t *testing.T) {
}
for _, test := range tests {
- res, _, err := decodePathAttr(bytes.NewBuffer(test.input))
+ res, _, err := decodePathAttr(bytes.NewBuffer(test.input), &DecodingOptions{})
if test.wantFail && err == nil {
t.Errorf("Expected error did not happen for test %q", test.name)
@@ -264,6 +264,7 @@ func TestDecodeASPath(t *testing.T) {
input []byte
wantFail bool
explicitLength uint16
+ use4OctetASNs bool
expected *PathAttribute
}{
{
@@ -308,6 +309,28 @@ func TestDecodeASPath(t *testing.T) {
},
},
},
+ {
+ name: "32 bit ASNs in AS_PATH",
+ input: []byte{
+ 1, // AS_SEQUENCE
+ 3, // Path Length
+ 0, 0, 0, 100, 0, 0, 0, 222, 0, 0, 0, 240,
+ },
+ wantFail: false,
+ use4OctetASNs: true,
+ expected: &PathAttribute{
+ Length: 14,
+ Value: ASPath{
+ ASPathSegment{
+ Type: 1,
+ Count: 3,
+ ASNs: []uint32{
+ 100, 222, 240,
+ },
+ },
+ },
+ },
+ },
{
name: "Empty input",
input: []byte{},
@@ -326,28 +349,36 @@ func TestDecodeASPath(t *testing.T) {
}
for _, test := range tests {
- l := uint16(len(test.input))
- if test.explicitLength != 0 {
- l = test.explicitLength
- }
- pa := &PathAttribute{
- Length: l,
- }
- err := pa.decodeASPath(bytes.NewBuffer(test.input))
+ t.Run(test.name, func(t *testing.T) {
+ l := uint16(len(test.input))
+ if test.explicitLength != 0 {
+ l = test.explicitLength
+ }
+ pa := &PathAttribute{
+ Length: l,
+ }
- if test.wantFail && err == nil {
- t.Errorf("Expected error did not happen for test %q", test.name)
- }
+ asnLength := uint8(2)
+ if test.use4OctetASNs {
+ asnLength = 4
+ }
- if !test.wantFail && err != nil {
- t.Errorf("Unexpected failure for test %q: %v", test.name, err)
- }
+ err := pa.decodeASPath(bytes.NewBuffer(test.input), asnLength)
- if err != nil {
- continue
- }
+ if test.wantFail && err == nil {
+ t.Errorf("Expected error did not happen for test %q", test.name)
+ }
- assert.Equal(t, test.expected, pa)
+ if !test.wantFail && err != nil {
+ t.Errorf("Unexpected failure for test %q: %v", test.name, err)
+ }
+
+ if err != nil {
+ return
+ }
+
+ assert.Equal(t, test.expected, pa)
+ })
}
}
diff --git a/protocols/bgp/server/fsm.go b/protocols/bgp/server/fsm.go
index c4754257af98f0076e60a402b01f06966d4a0218..93223c7e5318ee38d2d1f9d77001bf1a34944bc1 100644
--- a/protocols/bgp/server/fsm.go
+++ b/protocols/bgp/server/fsm.go
@@ -56,6 +56,8 @@ type FSM struct {
capAddPathSend bool
capAddPathRecv bool
+ decodingOptions *packet.DecodingOptions
+
local net.IP
ribsInitialized bool
@@ -99,6 +101,7 @@ func newFSM2(peer *Peer) *FSM {
msgRecvFailCh: make(chan error),
stopMsgRecvCh: make(chan struct{}),
rib: peer.rib,
+ decodingOptions: &packet.DecodingOptions{},
}
}
diff --git a/protocols/bgp/server/fsm_established.go b/protocols/bgp/server/fsm_established.go
index ca68aecc2fe61957bc10d3582e6c7855a2ef0b0f..63d56e528c1ec7b230d2f8351ad6d3a6805bb22f 100644
--- a/protocols/bgp/server/fsm_established.go
+++ b/protocols/bgp/server/fsm_established.go
@@ -143,7 +143,7 @@ func (s *establishedState) keepaliveTimerExpired() (state, string) {
}
func (s *establishedState) msgReceived(data []byte) (state, string) {
- msg, err := packet.Decode(bytes.NewBuffer(data))
+ msg, err := packet.Decode(bytes.NewBuffer(data), s.fsm.decodingOptions)
if err != nil {
switch bgperr := err.(type) {
case packet.BGPError:
diff --git a/protocols/bgp/server/fsm_open_confirm.go b/protocols/bgp/server/fsm_open_confirm.go
index d2d25e4f533ec30d9a5d15aec25504d055c45f54..75947171112f5c29b528a25cd479a87cea594fe8 100644
--- a/protocols/bgp/server/fsm_open_confirm.go
+++ b/protocols/bgp/server/fsm_open_confirm.go
@@ -82,7 +82,7 @@ func (s *openConfirmState) keepaliveTimerExpired() (state, string) {
}
func (s *openConfirmState) msgReceived(data []byte) (state, string) {
- msg, err := packet.Decode(bytes.NewBuffer(data))
+ msg, err := packet.Decode(bytes.NewBuffer(data), s.fsm.decodingOptions)
if err != nil {
switch bgperr := err.(type) {
case packet.BGPError:
diff --git a/protocols/bgp/server/fsm_open_sent.go b/protocols/bgp/server/fsm_open_sent.go
index aba1193dd9b75010e50a3d4e2de932e9bc87647e..afbad880c40381989075e30947b63d1d03031188 100644
--- a/protocols/bgp/server/fsm_open_sent.go
+++ b/protocols/bgp/server/fsm_open_sent.go
@@ -74,7 +74,7 @@ func (s *openSentState) holdTimerExpired() (state, string) {
}
func (s *openSentState) msgReceived(data []byte) (state, string) {
- msg, err := packet.Decode(bytes.NewBuffer(data))
+ msg, err := packet.Decode(bytes.NewBuffer(data), s.fsm.decodingOptions)
if err != nil {
switch bgperr := err.(type) {
case packet.BGPError:
@@ -199,6 +199,8 @@ func (s *openSentState) processAddPathCapability(addPathCap packet.AddPathCapabi
}
func (s *openSentState) processASN4Capability(cap packet.ASN4Capability) {
+ s.fsm.decodingOptions.Supports4OctetASN = true
+
if s.peerASNRcvd == packet.ASTransASN {
s.peerASNRcvd = cap.ASN4
}