Example #1
0
func selectRecord(recs []*pb.IpnsEntry, vals [][]byte) (int, error) {
	var best_seq uint64
	best_i := -1

	for i, r := range recs {
		if r == nil || r.GetSequence() < best_seq {
			continue
		}

		if best_i == -1 || r.GetSequence() > best_seq {
			best_seq = r.GetSequence()
			best_i = i
		} else if r.GetSequence() == best_seq {
			rt, err := u.ParseRFC3339(string(r.GetValidity()))
			if err != nil {
				continue
			}

			bestt, err := u.ParseRFC3339(string(recs[best_i].GetValidity()))
			if err != nil {
				continue
			}

			if rt.After(bestt) {
				best_i = i
			} else if rt == bestt {
				if bytes.Compare(vals[i], vals[best_i]) > 0 {
					best_i = i
				}
			}
		}
	}
	if best_i == -1 {
		return 0, errors.New("no usable records in given set")
	}

	return best_i, nil
}
Example #2
0
// ValidateIpnsRecord implements ValidatorFunc and verifies that the
// given 'val' is an IpnsEntry and that that entry is valid.
func ValidateIpnsRecord(k key.Key, val []byte) error {
	entry := new(pb.IpnsEntry)
	err := proto.Unmarshal(val, entry)
	if err != nil {
		return err
	}
	switch entry.GetValidityType() {
	case pb.IpnsEntry_EOL:
		t, err := u.ParseRFC3339(string(entry.GetValidity()))
		if err != nil {
			log.Debug("Failed parsing time for ipns record EOL")
			return err
		}
		if time.Now().After(t) {
			return ErrExpiredRecord
		}
	default:
		return ErrUnrecognizedValidity
	}
	return nil
}
Example #3
0
func (dht *IpfsDHT) checkLocalDatastore(k key.Key) (*pb.Record, error) {
	log.Debugf("%s handleGetValue looking into ds", dht.self)
	dskey := k.DsKey()
	iVal, err := dht.datastore.Get(dskey)
	log.Debugf("%s handleGetValue looking into ds GOT %v", dht.self, iVal)

	if err == ds.ErrNotFound {
		return nil, nil
	}

	// if we got an unexpected error, bail.
	if err != nil {
		return nil, err
	}

	// if we have the value, send it back
	log.Debugf("%s handleGetValue success!", dht.self)

	byts, ok := iVal.([]byte)
	if !ok {
		return nil, fmt.Errorf("datastore had non byte-slice value for %v", dskey)
	}

	rec := new(pb.Record)
	err = proto.Unmarshal(byts, rec)
	if err != nil {
		log.Debug("Failed to unmarshal dht record from datastore")
		return nil, err
	}

	// if its our record, dont bother checking the times on it
	if peer.ID(rec.GetAuthor()) == dht.self {
		return rec, nil
	}

	var recordIsBad bool
	recvtime, err := u.ParseRFC3339(rec.GetTimeReceived())
	if err != nil {
		log.Info("either no receive time set on record, or it was invalid: ", err)
		recordIsBad = true
	}

	if time.Now().Sub(recvtime) > MaxRecordAge {
		log.Debug("old record found, tossing.")
		recordIsBad = true
	}

	// NOTE: we do not verify the record here beyond checking these timestamps.
	// we put the burden of checking the records on the requester as checking a record
	// may be computationally expensive

	if recordIsBad {
		err := dht.datastore.Delete(dskey)
		if err != nil {
			log.Error("Failed to delete bad record from datastore: ", err)
		}

		return nil, nil // can treat this as not having the record at all
	}

	return rec, nil
}