diff --git a/protocols/bgp/packet/path_attributes.go b/protocols/bgp/packet/path_attributes.go
index 1d51e4a48f97e7a16ced7d8dd1e59410ad078742..ee0c5d89329d571ed298e780f4824027c7876d1a 100644
--- a/protocols/bgp/packet/path_attributes.go
+++ b/protocols/bgp/packet/path_attributes.go
@@ -281,23 +281,23 @@ func (pa *PathAttribute) decodeASPath(buf *bytes.Buffer, asnLength uint8) error
func (pa *PathAttribute) decodeASN(buf *bytes.Buffer, asnSize uint8) (asn uint32, err error) {
if asnSize == 4 {
- return pa.decode4ByteASN(buf)
+ return decode4ByteASN(buf)
}
- return pa.decode2ByteASN(buf)
+ return decode2ByteASN(buf)
}
-func (pa *PathAttribute) decode4ByteASN(buf *bytes.Buffer) (asn uint32, err error) {
+func decode4ByteASN(buf *bytes.Buffer) (asn uint32, err error) {
asn4 := uint32(0)
err = decode.DecodeUint32(buf, &asn4)
if err != nil {
return 0, err
}
- return uint32(asn4), nil
+ return asn4, nil
}
-func (pa *PathAttribute) decode2ByteASN(buf *bytes.Buffer) (asn uint32, err error) {
+func decode2ByteASN(buf *bytes.Buffer) (asn uint32, err error) {
asn2 := uint16(0)
err = decode.DecodeUint16(buf, &asn2)
if err != nil {
diff --git a/protocols/bgp/packet/path_attributes_test.go b/protocols/bgp/packet/path_attributes_test.go
index dcbcb3bbb6baa03b5f87eb71e12b1400c48033a6..fef287f8fe9657ca2ef0919e67ce2114c14f2663 100644
--- a/protocols/bgp/packet/path_attributes_test.go
+++ b/protocols/bgp/packet/path_attributes_test.go
@@ -2336,3 +2336,27 @@ func TestFourBytesToUint32(t *testing.T) {
}
}
}
+
+func TestDecode4ByteASN(t *testing.T) {
+ tests := []struct {
+ name string
+ input *bytes.Buffer
+ expected uint32
+ }{
+ {
+ name: "Test #1",
+ input: bytes.NewBuffer([]byte{0b00000000, 0b00000011, 0b00010011, 0b11100101}),
+ expected: 201701,
+ },
+ }
+
+ for _, test := range tests {
+ res, err := decode4ByteASN(test.input)
+ if err != nil {
+ t.Errorf("error in test %q: %v", test.name, err)
+ continue
+ }
+
+ assert.Equal(t, test.expected, res, test.name)
+ }
+}
diff --git a/protocols/bgp/server/bmp_router.go b/protocols/bgp/server/bmp_router.go
index 1f4b522a97ed346239bfba7dadcadbcbc967b75e..5e7245aae64871ace7864b6a8207f0c3bbfd3a89 100644
--- a/protocols/bgp/server/bmp_router.go
+++ b/protocols/bgp/server/bmp_router.go
@@ -158,7 +158,9 @@ func (r *Router) processRouteMonitoringMsg(msg *bmppkt.RouteMonitoringMsg) {
}
s := n.fsm.state.(*establishedState)
- s.msgReceived(msg.BGPUpdate, s.fsm.decodeOptions())
+ opt := s.fsm.decodeOptions()
+ opt.Use32BitASN = !msg.PerPeerHeader.GetAFlag()
+ s.msgReceived(msg.BGPUpdate, opt)
}
func (r *Router) processInitiationMsg(msg *bmppkt.InitiationMessage) {
@@ -385,9 +387,6 @@ func (p *peer) configureBySentOpen(msg *packet.BGPOpen) {
MaxPaths: 10,
}
}
- case packet.ASN4CapabilityCode:
- asn4Cap := cap.Value.(packet.ASN4Capability)
- p.localASN = asn4Cap.ASN4
}
}
}
diff --git a/protocols/bgp/server/bmp_server_test.go b/protocols/bgp/server/bmp_server_test.go
index 7f8c605eb2f7d3e54974d2ac3181b00dc44805e3..fef31b5c9822d4e5fdad754283adfb9da0d87ee7 100644
--- a/protocols/bgp/server/bmp_server_test.go
+++ b/protocols/bgp/server/bmp_server_test.go
@@ -224,7 +224,7 @@ func TestBMPServer(t *testing.T) {
0, // Msg Type (route monitoring)
0, // Peer Type (global instance peer)
- 0, // Peer Flags
+ 0b00100000, // Peer Flags
0, 0, 0, 0, 0, 0, 0, 123, // Peer Distinguisher
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 1, 1, 1, // Peer Address (10.1.1.1)
0, 0, 0, 200, // Peer AS = 200
@@ -315,7 +315,7 @@ func TestBMPServer(t *testing.T) {
0, // Msg Type (route monitoring)
0, // Peer Type (global instance peer)
- 0, // Peer Flags
+ 0b00100000, // Peer Flags
0, 0, 0, 0, 0, 0, 0, 123, // Peer Distinguisher
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 1, 2, 1, // Peer Address (10.1.2.1)
0, 0, 0, 222, // Peer AS = 222
diff --git a/protocols/bmp/packet/per_peer_header.go b/protocols/bmp/packet/per_peer_header.go
index 7723d826f7a81b17f716d31a1b3bbdc3889bf3d1..6fdfedbe3e15abbca30dd9f044d13b489febea62 100644
--- a/protocols/bmp/packet/per_peer_header.go
+++ b/protocols/bmp/packet/per_peer_header.go
@@ -60,8 +60,14 @@ func decodePerPeerHeader(buf *bytes.Buffer) (*PerPeerHeader, error) {
// GetIPVersion gets the IP version of the BGP session
func (p *PerPeerHeader) GetIPVersion() uint8 {
- if p.PeerFlags>>7 == 1 {
+ if p.PeerFlags&0b10000000 == 0b10000000 {
return 6
}
+
return 4
}
+
+// GetAFlag checks if the A flag is set
+func (p *PerPeerHeader) GetAFlag() bool {
+ return p.PeerFlags&0b00100000 == 0b00100000
+}
diff --git a/protocols/bmp/packet/per_peer_header_test.go b/protocols/bmp/packet/per_peer_header_test.go
index 8c51ee6c9b286faf927893d20ab093fe792ce0ce..17f48724cb3362b5929d70f9d1bb6a0baec2c8b2 100644
--- a/protocols/bmp/packet/per_peer_header_test.go
+++ b/protocols/bmp/packet/per_peer_header_test.go
@@ -125,28 +125,28 @@ func TestGetIPVersion(t *testing.T) {
{
name: "IPv4",
p: &PerPeerHeader{
- PeerFlags: 0,
+ PeerFlags: 0b00000000,
},
expected: 4,
},
{
name: "IPv4 #2",
p: &PerPeerHeader{
- PeerFlags: 127,
+ PeerFlags: 0b01000000,
},
expected: 4,
},
{
name: "IPv6",
p: &PerPeerHeader{
- PeerFlags: 128,
+ PeerFlags: 0b10000000,
},
expected: 6,
},
{
name: "IPv6 #2",
p: &PerPeerHeader{
- PeerFlags: 129,
+ PeerFlags: 0b11000000,
},
expected: 6,
},
@@ -154,6 +154,33 @@ func TestGetIPVersion(t *testing.T) {
for _, test := range tests {
v := test.p.GetIPVersion()
- assert.Equal(t, test.expected, v)
+ assert.Equal(t, test.expected, v, test.name)
+ }
+}
+
+func TestGetAFlag(t *testing.T) {
+ tests := []struct {
+ name string
+ input *PerPeerHeader
+ expected bool
+ }{
+ {
+ name: "Test #1",
+ input: &PerPeerHeader{
+ PeerFlags: 0b11011111,
+ },
+ expected: false,
+ },
+ {
+ name: "Test #2",
+ input: &PerPeerHeader{
+ PeerFlags: 0b00100000,
+ },
+ expected: true,
+ },
+ }
+
+ for _, test := range tests {
+ assert.Equal(t, test.expected, test.input.GetAFlag())
}
}
diff --git a/util/decode/decode.go b/util/decode/decode.go
index d32e2933272b85d7291ebeb2a8b9e9afd0d33220..5283ba79cce7302c99e02ba92f67905f02cbdffc 100644
--- a/util/decode/decode.go
+++ b/util/decode/decode.go
@@ -19,6 +19,7 @@ func Decode(buf *bytes.Buffer, fields []interface{}) error {
return nil
}
+// DecodeUint8 decodes an uint8
func DecodeUint8(buf *bytes.Buffer, x *uint8) error {
y, err := buf.ReadByte()
if err != nil {
@@ -29,6 +30,7 @@ func DecodeUint8(buf *bytes.Buffer, x *uint8) error {
return nil
}
+// DecodeUint16 decodes an uint16
func DecodeUint16(buf *bytes.Buffer, x *uint16) error {
a, err := buf.ReadByte()
if err != nil {
@@ -40,10 +42,11 @@ func DecodeUint16(buf *bytes.Buffer, x *uint16) error {
return err
}
- *x = uint16(a)*256 + uint16(b)
+ *x = uint16(a)<<8 + uint16(b)
return nil
}
+// DecodeUint32 decodes an uint32
func DecodeUint32(buf *bytes.Buffer, x *uint32) error {
a, err := buf.ReadByte()
if err != nil {
@@ -65,6 +68,6 @@ func DecodeUint32(buf *bytes.Buffer, x *uint32) error {
return err
}
- *x = uint32(a)*256*256*256 + uint32(b)*256*256*256 + uint32(c)*256 + uint32(d)
+ *x = uint32(a)<<24 + uint32(b)<<16 + uint32(c)<<8 + uint32(d)
return nil
}