Function UpdatePathAttrs4ByteAs

internal/pkg/table/message.go:96–225

(logger *slog.Logger, msg *bgp.BGPUpdate)

}

func UpdatePathAttrs4ByteAs(logger *slog.Logger, msg *bgp.BGPUpdate) {
	var asAttr *bgp.PathAttributeAsPath
	var as4Attr *bgp.PathAttributeAs4Path
	asAttrPos := 0
	as4AttrPos := 0
	for i, attr := range msg.PathAttributes {
		switch a := attr.(type) {
		case *bgp.PathAttributeAsPath:
			asAttr = a
			for j, param := range asAttr.Value {
				as2Param, ok := param.(*bgp.AsPathParam)
				if ok {
					asPath := make([]uint32, 0, len(as2Param.AS))
					for _, as := range as2Param.AS {
						asPath = append(asPath, uint32(as))
					}
					as4Param := bgp.NewAs4PathParam(as2Param.Type, asPath)
					asAttr.Value[j] = as4Param
				}
			}
			asAttrPos = i
			msg.PathAttributes[i] = asAttr
		case *bgp.PathAttributeAs4Path:
			as4AttrPos = i
			as4Attr = a
		}
	}

	if as4Attr != nil {
		msg.PathAttributes = append(msg.PathAttributes[:as4AttrPos], msg.PathAttributes[as4AttrPos+1:]...)
		// Adjust asAttrPos if AS4_PATH was before AS_PATH
		// (AS4_PATH removal shifts the indices of subsequent attributes)
		if as4AttrPos < asAttrPos {
			asAttrPos--
		}
	}

	if asAttr == nil || as4Attr == nil {
		return
	}

	asLen := 0
	asConfedLen := 0
	asParams := make([]bgp.AsPathParamInterface, 0, len(asAttr.Value))
	for _, param := range asAttr.Value {
		asLen += param.ASLen()
		switch param.GetType() {
		case bgp.BGP_ASPATH_ATTR_TYPE_CONFED_SET:
			asConfedLen++
		case bgp.BGP_ASPATH_ATTR_TYPE_CONFED_SEQ:
			asConfedLen += len(param.GetAS())
		}
		asParams = append(asParams, param)
	}

	as4Len := 0
	var as4Params []bgp.AsPathParamInterface
	if as4Attr != nil {