diff options
Diffstat (limited to 'packet')
| -rw-r--r-- | packet/bgp/bgp.go | 125 |
1 files changed, 124 insertions, 1 deletions
diff --git a/packet/bgp/bgp.go b/packet/bgp/bgp.go index 798644ec..a29a6962 100644 --- a/packet/bgp/bgp.go +++ b/packet/bgp/bgp.go @@ -3606,7 +3606,8 @@ const ( BGP_ATTR_TYPE_TUNNEL_ENCAP _ _ - BGP_ATTR_TYPE_AIGP // = 26 + BGP_ATTR_TYPE_AIGP // = 26 + BGP_ATTR_TYPE_LARGE_COMMUNITY BGPAttrType = 41 ) // NOTIFICATION Error Code RFC 4271 4.5. @@ -3792,6 +3793,7 @@ var PathAttrFlags map[BGPAttrType]BGPAttrFlag = map[BGPAttrType]BGPAttrFlag{ BGP_ATTR_TYPE_PMSI_TUNNEL: BGP_ATTR_FLAG_TRANSITIVE | BGP_ATTR_FLAG_OPTIONAL, BGP_ATTR_TYPE_TUNNEL_ENCAP: BGP_ATTR_FLAG_TRANSITIVE | BGP_ATTR_FLAG_OPTIONAL, BGP_ATTR_TYPE_AIGP: BGP_ATTR_FLAG_OPTIONAL, + BGP_ATTR_TYPE_LARGE_COMMUNITY: BGP_ATTR_FLAG_TRANSITIVE | BGP_ATTR_FLAG_OPTIONAL, } type PathAttributeInterface interface { @@ -6651,6 +6653,125 @@ func NewPathAttributeAigp(values []AigpTLV) *PathAttributeAigp { } } +type LargeCommunity struct { + ASN uint32 + LocalData1 uint32 + LocalData2 uint32 +} + +func (c *LargeCommunity) Serialize() ([]byte, error) { + buf := make([]byte, 12) + binary.BigEndian.PutUint32(buf, c.ASN) + binary.BigEndian.PutUint32(buf[4:], c.LocalData1) + binary.BigEndian.PutUint32(buf[8:], c.LocalData2) + return buf, nil +} + +func (c *LargeCommunity) String() string { + return fmt.Sprintf("%d:%d:%d", c.ASN, c.LocalData1, c.LocalData2) +} + +func NewLargeCommunity(asn, data1, data2 uint32) *LargeCommunity { + return &LargeCommunity{ + ASN: asn, + LocalData1: data1, + LocalData2: data2, + } +} + +func ParseLargeCommunity(value string) (*LargeCommunity, error) { + elems := strings.Split(value, ":") + if len(elems) != 3 { + return nil, fmt.Errorf("invalid large community format") + } + v := make([]uint32, 0, 3) + for _, elem := range elems { + e, err := strconv.ParseUint(elem, 10, 32) + if err != nil { + return nil, fmt.Errorf("invalid large community format") + } + v = append(v, uint32(e)) + } + return NewLargeCommunity(v[0], v[1], v[2]), nil +} + +type PathAttributeLargeCommunities struct { + PathAttribute + Values []*LargeCommunity +} + +func (p *PathAttributeLargeCommunities) DecodeFromBytes(data []byte) error { + err := p.PathAttribute.DecodeFromBytes(data) + if err != nil { + return err + } + + rest := p.PathAttribute.Value + + if len(rest)%12 != 0 { + eCode := uint8(BGP_ERROR_UPDATE_MESSAGE_ERROR) + eSubCode := uint8(BGP_ERROR_SUB_ATTRIBUTE_LENGTH_ERROR) + return NewMessageError(eCode, eSubCode, nil, "large communities length isn't correct") + } + + p.Values = make([]*LargeCommunity, 0, len(rest)/12) + + for len(rest) >= 12 { + asn := binary.BigEndian.Uint32(rest[:4]) + data1 := binary.BigEndian.Uint32(rest[4:8]) + data2 := binary.BigEndian.Uint32(rest[8:12]) + p.Values = append(p.Values, NewLargeCommunity(asn, data1, data2)) + rest = rest[12:] + } + return nil +} + +func (p *PathAttributeLargeCommunities) Serialize() ([]byte, error) { + buf := make([]byte, 0) + for _, t := range p.Values { + bbuf, err := t.Serialize() + if err != nil { + return nil, err + } + buf = append(buf, bbuf...) + } + p.PathAttribute.Value = buf + return p.PathAttribute.Serialize() +} + +func (p *PathAttributeLargeCommunities) String() string { + buf := bytes.NewBuffer(make([]byte, 0, 32)) + buf.WriteString("{LargeCommunity: [ ") + ss := []string{} + for _, v := range p.Values { + ss = append(ss, v.String()) + } + buf.WriteString(strings.Join(ss, ", ")) + buf.WriteString("]}") + return buf.String() +} + +func (p *PathAttributeLargeCommunities) MarshalJSON() ([]byte, error) { + return json.Marshal(struct { + Type BGPAttrType `json:"type"` + Value []*LargeCommunity `json:"value"` + }{ + Type: p.GetType(), + Value: p.Values, + }) +} + +func NewPathAttributeLargeCommunities(values []*LargeCommunity) *PathAttributeLargeCommunities { + t := BGP_ATTR_TYPE_LARGE_COMMUNITY + return &PathAttributeLargeCommunities{ + PathAttribute: PathAttribute{ + Flags: PathAttrFlags[t], + Type: t, + }, + Values: values, + } +} + type PathAttributeUnknown struct { PathAttribute } @@ -6698,6 +6819,8 @@ func GetPathAttribute(data []byte) (PathAttributeInterface, error) { return &PathAttributePmsiTunnel{}, nil case BGP_ATTR_TYPE_AIGP: return &PathAttributeAigp{}, nil + case BGP_ATTR_TYPE_LARGE_COMMUNITY: + return &PathAttributeLargeCommunities{}, nil } return &PathAttributeUnknown{}, nil } |