summaryrefslogtreecommitdiffhomepage
path: root/pkg/packet/bgp
diff options
context:
space:
mode:
Diffstat (limited to 'pkg/packet/bgp')
-rw-r--r--pkg/packet/bgp/bgp.go107
-rw-r--r--pkg/packet/bgp/prefix_sid.go143
-rw-r--r--pkg/packet/bgp/prefix_sid_test.go34
3 files changed, 274 insertions, 10 deletions
diff --git a/pkg/packet/bgp/bgp.go b/pkg/packet/bgp/bgp.go
index 84604312..f72a3706 100644
--- a/pkg/packet/bgp/bgp.go
+++ b/pkg/packet/bgp/bgp.go
@@ -31,7 +31,8 @@ import (
)
type MarshallingOption struct {
- AddPath map[RouteFamily]BGPAddPathMode
+ AddPath map[RouteFamily]BGPAddPathMode
+ Attributes map[BGPAttrType]bool
}
func IsAddPathEnabled(decode bool, f RouteFamily, options []*MarshallingOption) bool {
@@ -49,6 +50,18 @@ func IsAddPathEnabled(decode bool, f RouteFamily, options []*MarshallingOption)
}
return false
}
+func IsAttributePresent(attr BGPAttrType, options []*MarshallingOption) bool {
+ for _, opt := range options {
+ if opt == nil {
+ continue
+ }
+ if o := opt.Attributes; o != nil {
+ _, ok := o[attr]
+ return ok
+ }
+ }
+ return false
+}
const (
AFI_IP = 1
@@ -1588,9 +1601,17 @@ type MPLSLabelStack struct {
Labels []uint32
}
-func (l *MPLSLabelStack) DecodeFromBytes(data []byte) error {
+func (l *MPLSLabelStack) DecodeFromBytes(data []byte, options ...*MarshallingOption) error {
labels := []uint32{}
foundBottom := false
+ bottomExpected := true
+ if IsAttributePresent(BGP_ATTR_TYPE_PREFIX_SID, options) {
+ // If Update carries Prefix SID attribute then there is no a label stack,
+ // but just 3 bytes which are used to carry the lower portion of Prefix SID.
+ // There is no bottom stack indication in this case. Once 3 bytes are stored
+ // breaking out of the loop.
+ bottomExpected = false
+ }
for len(data) >= 3 {
label := uint32(data[0])<<16 | uint32(data[1])<<8 | uint32(data[2])
if label == WITHDRAW_LABEL || label == ZERO_LABEL {
@@ -1599,6 +1620,11 @@ func (l *MPLSLabelStack) DecodeFromBytes(data []byte) error {
}
data = data[3:]
labels = append(labels, label>>4)
+ if !bottomExpected {
+ // Faking found bottom.
+ foundBottom = true
+ break
+ }
if label&1 == 1 {
foundBottom = true
break
@@ -1613,7 +1639,7 @@ func (l *MPLSLabelStack) DecodeFromBytes(data []byte) error {
return nil
}
-func (l *MPLSLabelStack) Serialize() ([]byte, error) {
+func (l *MPLSLabelStack) Serialize(options ...*MarshallingOption) ([]byte, error) {
buf := make([]byte, len(l.Labels)*3)
for i, label := range l.Labels {
if label == WITHDRAW_LABEL {
@@ -1624,6 +1650,13 @@ func (l *MPLSLabelStack) Serialize() ([]byte, error) {
buf[i*3+1] = byte((label >> 8) & 0xff)
buf[i*3+2] = byte(label & 0xff)
}
+ if IsAttributePresent(BGP_ATTR_TYPE_PREFIX_SID, options) {
+ // If Update carries Prefix SID attribute then there is no a label stack,
+ // but just 3 bytes which are used to carry the lower portion of Prefix SID.
+ // No need BoS bit set
+ return buf, nil
+ }
+
buf[len(buf)-1] |= 1
return buf, nil
}
@@ -1721,7 +1754,7 @@ func (l *LabeledVPNIPAddrPrefix) DecodeFromBytes(data []byte, options ...*Marsha
}
l.Length = uint8(data[0])
data = data[1:]
- l.Labels.DecodeFromBytes(data)
+ l.Labels.DecodeFromBytes(data, options...)
if int(l.Length)-8*(l.Labels.Len()) < 0 {
l.Labels.Labels = []uint32{}
}
@@ -1746,7 +1779,7 @@ func (l *LabeledVPNIPAddrPrefix) Serialize(options ...*MarshallingOption) ([]byt
}
}
buf = append(buf, l.Length)
- lbuf, err := l.Labels.Serialize()
+ lbuf, err := l.Labels.Serialize(options...)
if err != nil {
return nil, err
}
@@ -8480,6 +8513,7 @@ var PathAttrFlags map[BGPAttrType]BGPAttrFlag = map[BGPAttrType]BGPAttrFlag{
BGP_ATTR_TYPE_AIGP: BGP_ATTR_FLAG_OPTIONAL,
BGP_ATTR_TYPE_LARGE_COMMUNITY: BGP_ATTR_FLAG_TRANSITIVE | BGP_ATTR_FLAG_OPTIONAL,
BGP_ATTR_TYPE_LS: BGP_ATTR_FLAG_OPTIONAL,
+ BGP_ATTR_TYPE_PREFIX_SID: BGP_ATTR_FLAG_TRANSITIVE | BGP_ATTR_FLAG_OPTIONAL,
}
// getPathAttrFlags returns BGP Path Attribute flags value from its type and
@@ -9515,6 +9549,7 @@ type PathAttributeMpReachNLRI struct {
}
func (p *PathAttributeMpReachNLRI) DecodeFromBytes(data []byte, options ...*MarshallingOption) error {
+
value, err := p.PathAttribute.DecodeFromBytes(data, options...)
if err != nil {
return err
@@ -12325,6 +12360,56 @@ func NewPathAttributeUnknown(flags BGPAttrFlag, typ BGPAttrType, value []byte) *
}
}
+// BGPUpdateAttributes defines a map with a key as bgp attribute type
+// and value as bool. Value set to true indicates that the attribute specified by the key
+// exists in the bgp update.
+type BGPUpdateAttributes struct {
+ Attribute map[BGPAttrType]bool
+}
+
+func GetBGPUpdateAttributes(data []byte) map[BGPAttrType]bool {
+ m := make(map[BGPAttrType]bool)
+ for p := 0; p < len(data); {
+ flag := data[p]
+ p++
+ if p < len(data) {
+ t := data[p]
+ m[BGPAttrType(t)] = true
+ } else {
+ break
+ }
+ p++
+ var l uint16
+ // Checking for Extened
+ if flag&0x10 == 0x10 {
+ if p+2 <= len(data) {
+ l = binary.BigEndian.Uint16(data[p : p+2])
+ } else {
+ break
+ }
+ p += 2
+ } else {
+ if p < len(data) {
+ l = uint16(data[p])
+ p++
+ } else {
+ break
+ }
+ }
+ p += int(l)
+ }
+ return m
+}
+
+func GetBGPUpdateAttributesFromMsg(msg *BGPUpdate) map[BGPAttrType]bool {
+ m := make(map[BGPAttrType]bool)
+ for _, p := range msg.PathAttributes {
+ m[p.GetType()] = true
+ }
+
+ return m
+}
+
func GetPathAttribute(data []byte) (PathAttributeInterface, error) {
if len(data) < 2 {
eCode := uint8(BGP_ERROR_UPDATE_MESSAGE_ERROR)
@@ -12440,6 +12525,11 @@ func (msg *BGPUpdate) DecodeFromBytes(data []byte, options ...*MarshallingOption
if len(data) < int(msg.TotalPathAttributeLen) {
return NewMessageError(eCode, eSubCode, nil, "path total attribute length exceeds message length")
}
+ attributes := GetBGPUpdateAttributes(data)
+ o := MarshallingOption{
+ Attributes: attributes,
+ }
+ options = append(options, &o)
msg.PathAttributes = []PathAttributeInterface{}
for pathlen := msg.TotalPathAttributeLen; pathlen > 0; {
@@ -12457,7 +12547,6 @@ func (msg *BGPUpdate) DecodeFromBytes(data []byte, options ...*MarshallingOption
if err != nil {
return err
}
-
err = p.DecodeFromBytes(data, options...)
if err != nil {
e = err.(*MessageError)
@@ -12519,6 +12608,11 @@ func (msg *BGPUpdate) Serialize(options ...*MarshallingOption) ([]byte, error) {
msg.WithdrawnRoutesLen = uint16(len(wbuf) - 2)
binary.BigEndian.PutUint16(wbuf, msg.WithdrawnRoutesLen)
+ attributes := GetBGPUpdateAttributesFromMsg(msg)
+ o := MarshallingOption{
+ Attributes: attributes,
+ }
+ options = append(options, &o)
pbuf := make([]byte, 2)
for _, p := range msg.PathAttributes {
onepbuf, err := p.Serialize(options...)
@@ -12538,6 +12632,7 @@ func (msg *BGPUpdate) Serialize(options ...*MarshallingOption) ([]byte, error) {
}
buf = append(buf, nbuf...)
}
+
return buf, nil
}
diff --git a/pkg/packet/bgp/prefix_sid.go b/pkg/packet/bgp/prefix_sid.go
index 7dd90082..a7983bcd 100644
--- a/pkg/packet/bgp/prefix_sid.go
+++ b/pkg/packet/bgp/prefix_sid.go
@@ -5,6 +5,10 @@ import (
"encoding/binary"
"encoding/json"
"fmt"
+ "net"
+
+ "github.com/golang/protobuf/ptypes"
+ api "github.com/osrg/gobgp/api"
)
const (
@@ -14,9 +18,8 @@ const (
type TLVType uint8
type TLV struct {
- Type TLVType
- Length uint16
- Reserved uint8
+ Type TLVType
+ Length uint16
}
func (s *TLV) Len() int {
@@ -391,7 +394,7 @@ func (s *SRv6InformationSubTLV) MarshalJSON() ([]byte, error) {
func (s *SRv6InformationSubTLV) String() string {
var buf bytes.Buffer
- buf.WriteString(fmt.Sprintf("SID: %s ", string(s.SID)))
+ buf.WriteString(fmt.Sprintf("SID: %s ", net.IP(s.SID).To16().String()))
buf.WriteString(fmt.Sprintf("Flag: %d ", s.Flags))
buf.WriteString(fmt.Sprintf("Endpoint Behavior: %d ", s.EndpointBehavior))
for _, tlv := range s.SubSubTLVs {
@@ -540,3 +543,135 @@ func (s *SRv6SIDStructureSubSubTLV) String() string {
s.TranspositionOffset,
)
}
+
+func NewPathAttributePrefixSID(psid *api.PrefixSID) (*PathAttributePrefixSID, error) {
+ t := BGP_ATTR_TYPE_PREFIX_SID
+ s := &PathAttributePrefixSID{
+ PathAttribute: PathAttribute{
+ Flags: PathAttrFlags[t],
+ Type: t,
+ },
+ TLVs: make([]PrefixSIDTLVInterface, 0),
+ }
+ for _, raw := range psid.Tlvs {
+ var tlv ptypes.DynamicAny
+ if err := ptypes.UnmarshalAny(raw, &tlv); err != nil {
+ return nil, err
+ }
+ switch v := tlv.Message.(type) {
+ case *api.SRv6L3ServiceTLV:
+ tlvLength, tlvs, err := UnmarshalSubTLVs(v.SubTlvs)
+ if err != nil {
+ return nil, err
+ }
+ o := &SRv6L3ServiceAttribute{
+ TLV: TLV{
+ Type: TLVType(5),
+ Length: tlvLength,
+ },
+ }
+ s.PathAttribute.Length += tlvLength
+ // Storing Sub TLVs in a Service TLV
+ o.SubTLVs = append(o.SubTLVs, tlvs...)
+ // Adding Service TLV to Path Attribute TLV slice.
+ s.TLVs = append(s.TLVs, o)
+ default:
+ return nil, fmt.Errorf("unknown or not implemented Prefix SID type: %+v", v)
+ }
+ }
+ // Final Path Attribute Length is 3 bytes of the header and 1 byte Reserved1
+ s.PathAttribute.Length += (3 + 1)
+ return s, nil
+}
+
+func UnmarshalSubTLVs(stlvs map[uint32]*api.SRv6TLV) (uint16, []PrefixSIDTLVInterface, error) {
+ p := make([]PrefixSIDTLVInterface, 0, len(stlvs))
+ l := uint16(0)
+ // v.SubTlvs is a map by sub tlv type and the value is a slice of sub tlvs of the specific type
+ for t, tlv := range stlvs {
+ switch t {
+ case 1:
+ // Sub TLV Type 1 is SRv6 Informational Sub TLV
+ for _, stlvRaw := range tlv.Tlv {
+ // Instantiating Information Sub TLV
+ info := &SRv6InformationSubTLV{
+ SubTLV: SubTLV{
+ Type: SubTLVType(1),
+ },
+ SubSubTLVs: make([]PrefixSIDTLVInterface, 0),
+ }
+ var raw ptypes.DynamicAny
+ if err := ptypes.UnmarshalAny(stlvRaw, &raw); err != nil {
+ return 0, nil, err
+ }
+ infoProto := raw.Message.(*api.SRv6InformationSubTLV)
+ info.SID = make([]byte, len(infoProto.Sid))
+ copy(info.SID, infoProto.Sid)
+ // TODO Once RFC is published add processing of flags
+ info.Flags = 0
+ info.EndpointBehavior = uint16(infoProto.EndpointBehavior)
+ var sstlvslength uint16
+ var sstlvs []PrefixSIDTLVInterface
+ if len(infoProto.SubSubTlvs) != 0 {
+ // Processing Sub Sub TLVs
+ var err error
+ sstlvslength, sstlvs, err = UnmarshalSubSubTLVs(infoProto.SubSubTlvs)
+ if err != nil {
+ return 0, nil, err
+ }
+ info.SubSubTLVs = append(info.SubSubTLVs, sstlvs...)
+ }
+ // SRv6 Information Sub TLV length consists 1 byte Resrved2, 16 bytes SID, 1 byte flags, 2 bytes Endpoint Behavior
+ // 1 byte Reserved3 and length of Sub Sub TLVs
+ info.SubTLV.Length = 1 + 16 + 1 + 2 + 1 + sstlvslength
+ // For total Srv6 Information Sub TLV length, adding 3 bytes of the Sub TLV header
+ l += info.SubTLV.Length + 4
+ p = append(p, info)
+ }
+ default:
+ return 0, nil, fmt.Errorf("unknown or not implemented Prefix SID Sub TLV type: %d", t)
+ }
+ }
+
+ return l, p, nil
+}
+
+func UnmarshalSubSubTLVs(stlvs map[uint32]*api.SRv6TLV) (uint16, []PrefixSIDTLVInterface, error) {
+ p := make([]PrefixSIDTLVInterface, 0)
+ l := uint16(0)
+ // v.SubTlvs is a map by sub tlv type and the value is a slice of sub tlvs of the specific type
+ for t, tlv := range stlvs {
+ switch t {
+ case 1:
+ // Sub Sub TLV Type 1 is SRv6 Structure Sub Sub TLV
+ for _, stlvRaw := range tlv.Tlv {
+ // Instantiating Information Sub TLV
+ structure := &SRv6SIDStructureSubSubTLV{
+ SubSubTLV: SubSubTLV{
+ Type: SubSubTLVType(1),
+ Length: 6,
+ },
+ }
+ var raw ptypes.DynamicAny
+ if err := ptypes.UnmarshalAny(stlvRaw, &raw); err != nil {
+ return 0, nil, err
+ }
+ structureProto := raw.Message.(*api.SRv6StructureSubSubTLV)
+ structure.LocalBlockLength = uint8(structureProto.LocalBlockLength)
+ structure.LocatorNodeLength = uint8(structureProto.LocalNodeLength)
+ structure.FunctionLength = uint8(structureProto.FunctionLength)
+ structure.ArgumentLength = uint8(structureProto.ArgumentLength)
+ structure.TranspositionLength = uint8(structureProto.TranspositionLength)
+ structure.TranspositionOffset = uint8(structureProto.TranspositionOffset)
+
+ // SRv6 Structure Sub Sub TLV length consists of header 3 bytes, 6 bytes of value
+ l += (3 + 6)
+ p = append(p, structure)
+ }
+ default:
+ return 0, nil, fmt.Errorf("unknown or not implemented Prefix SID Sub TLV type: %d", t)
+ }
+ }
+
+ return l, p, nil
+}
diff --git a/pkg/packet/bgp/prefix_sid_test.go b/pkg/packet/bgp/prefix_sid_test.go
index 2df8a3a3..a286228c 100644
--- a/pkg/packet/bgp/prefix_sid_test.go
+++ b/pkg/packet/bgp/prefix_sid_test.go
@@ -3,6 +3,9 @@ package bgp
import (
"bytes"
"testing"
+
+ "github.com/golang/protobuf/ptypes/any"
+ api "github.com/osrg/gobgp/api"
)
func TestRoundTripSubSubTLV(t *testing.T) {
@@ -88,3 +91,34 @@ func TestRoundTripPrefixSID(t *testing.T) {
})
}
}
+
+func TestNewPathAttributePrefixSID(t *testing.T) {
+ tests := []struct {
+ name string
+ input *api.PrefixSID
+ }{
+ {
+ name: "path attribute srv6 prefix sid",
+ input: &api.PrefixSID{
+ Tlvs: []*any.Any{
+ {
+ TypeUrl: "type.googleapis.com/gobgpapi.SRv6L3ServiceTLV",
+ Value: []byte{10, 157, 1, 8, 1, 18, 152, 1, 10, 149, 1, 10, 50, 116, 121, 112, 101, 46, 103, 111, 111, 103, 108, 101, 97, 112, 105, 115, 46, 99, 111, 109, 47, 103, 111, 98, 103, 112, 97, 112, 105, 46, 83, 82, 118, 54, 73, 110, 102, 111, 114, 109, 97, 116, 105, 111, 110, 83, 117, 98, 84, 76, 86, 18, 95, 10, 16, 32, 1, 0, 0, 0, 5, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 18, 0, 24, 17, 34, 71, 8, 1, 18, 67, 10, 65, 10, 51, 116, 121, 112, 101, 46, 103, 111, 111, 103, 108, 101, 97, 112, 105, 115, 46, 99, 111, 109, 47, 103, 111, 98, 103, 112, 97, 112, 105, 46, 83, 82, 118, 54, 83, 116, 114, 117, 99, 116, 117, 114, 101, 83, 117, 98, 83, 117, 98, 84, 76, 86, 18, 10, 8, 40, 16, 24, 24, 16, 40, 16, 48, 64},
+ },
+ },
+ },
+ },
+ }
+ for _, tt := range tests {
+ t.Run(tt.name, func(t *testing.T) {
+ p, err := NewPathAttributePrefixSID(tt.input)
+ if err != nil {
+ t.Fatalf("failed with error: %+v", err)
+ }
+ t.Logf("resulting prefix sid: %s", p.String())
+ b, _ := p.Serialize()
+ t.Logf("serialized prefix sid: %s", string(b))
+
+ })
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 08:21:25 +0000