-
Notifications
You must be signed in to change notification settings - Fork 1k
/
record.go
253 lines (220 loc) · 7.61 KB
/
record.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
package peer
import (
"fmt"
"sync"
"time"
"github.com/libp2p/go-libp2p/core/internal/catch"
"github.com/libp2p/go-libp2p/core/peer/pb"
"github.com/libp2p/go-libp2p/core/record"
ma "github.com/multiformats/go-multiaddr"
"google.golang.org/protobuf/proto"
)
//go:generate protoc --proto_path=$PWD:$PWD/../.. --go_out=. --go_opt=Mpb/peer_record.proto=./pb pb/peer_record.proto
var _ record.Record = (*PeerRecord)(nil)
func init() {
record.RegisterType(&PeerRecord{})
}
// PeerRecordEnvelopeDomain is the domain string used for peer records contained in an Envelope.
const PeerRecordEnvelopeDomain = "libp2p-peer-record"
// PeerRecordEnvelopePayloadType is the type hint used to identify peer records in an Envelope.
// Defined in https://github.com/multiformats/multicodec/blob/master/table.csv
// with name "libp2p-peer-record".
var PeerRecordEnvelopePayloadType = []byte{0x03, 0x01}
// PeerRecord contains information that is broadly useful to share with other peers,
// either through a direct exchange (as in the libp2p identify protocol), or through
// a Peer Routing provider, such as a DHT.
//
// Currently, a PeerRecord contains the public listen addresses for a peer, but this
// is expected to expand to include other information in the future.
//
// PeerRecords are ordered in time by their Seq field. Newer PeerRecords must have
// greater Seq values than older records. The NewPeerRecord function will create
// a PeerRecord with a timestamp-based Seq value. The other PeerRecord fields should
// be set by the caller:
//
// rec := peer.NewPeerRecord()
// rec.PeerID = aPeerID
// rec.Addrs = someAddrs
//
// Alternatively, you can construct a PeerRecord struct directly and use the TimestampSeq
// helper to set the Seq field:
//
// rec := peer.PeerRecord{PeerID: aPeerID, Addrs: someAddrs, Seq: peer.TimestampSeq()}
//
// Failing to set the Seq field will not result in an error, however, a PeerRecord with a
// Seq value of zero may be ignored or rejected by other peers.
//
// PeerRecords are intended to be shared with other peers inside a signed
// routing.Envelope, and PeerRecord implements the routing.Record interface
// to facilitate this.
//
// To share a PeerRecord, first call Sign to wrap the record in an Envelope
// and sign it with the local peer's private key:
//
// rec := &PeerRecord{PeerID: myPeerId, Addrs: myAddrs}
// envelope, err := rec.Sign(myPrivateKey)
//
// The resulting record.Envelope can be marshalled to a []byte and shared
// publicly. As a convenience, the MarshalSigned method will produce the
// Envelope and marshal it to a []byte in one go:
//
// rec := &PeerRecord{PeerID: myPeerId, Addrs: myAddrs}
// recordBytes, err := rec.MarshalSigned(myPrivateKey)
//
// To validate and unmarshal a signed PeerRecord from a remote peer,
// "consume" the containing envelope, which will return both the
// routing.Envelope and the inner Record. The Record must be cast to
// a PeerRecord pointer before use:
//
// envelope, untypedRecord, err := ConsumeEnvelope(envelopeBytes, PeerRecordEnvelopeDomain)
// if err != nil {
// handleError(err)
// return
// }
// peerRec := untypedRecord.(*PeerRecord)
type PeerRecord struct {
// PeerID is the ID of the peer this record pertains to.
PeerID ID
// Addrs contains the public addresses of the peer this record pertains to.
Addrs []ma.Multiaddr
// Seq is a monotonically-increasing sequence counter that's used to order
// PeerRecords in time. The interval between Seq values is unspecified,
// but newer PeerRecords MUST have a greater Seq value than older records
// for the same peer.
Seq uint64
}
// NewPeerRecord returns a PeerRecord with a timestamp-based sequence number.
// The returned record is otherwise empty and should be populated by the caller.
func NewPeerRecord() *PeerRecord {
return &PeerRecord{Seq: TimestampSeq()}
}
// PeerRecordFromAddrInfo creates a PeerRecord from an AddrInfo struct.
// The returned record will have a timestamp-based sequence number.
func PeerRecordFromAddrInfo(info AddrInfo) *PeerRecord {
rec := NewPeerRecord()
rec.PeerID = info.ID
rec.Addrs = info.Addrs
return rec
}
// PeerRecordFromProtobuf creates a PeerRecord from a protobuf PeerRecord
// struct.
func PeerRecordFromProtobuf(msg *pb.PeerRecord) (*PeerRecord, error) {
record := &PeerRecord{}
var id ID
if err := id.UnmarshalBinary(msg.PeerId); err != nil {
return nil, err
}
record.PeerID = id
record.Addrs = addrsFromProtobuf(msg.Addresses)
record.Seq = msg.Seq
return record, nil
}
var (
lastTimestampMu sync.Mutex
lastTimestamp uint64
)
// TimestampSeq is a helper to generate a timestamp-based sequence number for a PeerRecord.
func TimestampSeq() uint64 {
now := uint64(time.Now().UnixNano())
lastTimestampMu.Lock()
defer lastTimestampMu.Unlock()
// Not all clocks are strictly increasing, but we need these sequence numbers to be strictly
// increasing.
if now <= lastTimestamp {
now = lastTimestamp + 1
}
lastTimestamp = now
return now
}
// Domain is used when signing and validating PeerRecords contained in Envelopes.
// It is constant for all PeerRecord instances.
func (r *PeerRecord) Domain() string {
return PeerRecordEnvelopeDomain
}
// Codec is a binary identifier for the PeerRecord type. It is constant for all PeerRecord instances.
func (r *PeerRecord) Codec() []byte {
return PeerRecordEnvelopePayloadType
}
// UnmarshalRecord parses a PeerRecord from a byte slice.
// This method is called automatically when consuming a record.Envelope
// whose PayloadType indicates that it contains a PeerRecord.
// It is generally not necessary or recommended to call this method directly.
func (r *PeerRecord) UnmarshalRecord(bytes []byte) (err error) {
if r == nil {
return fmt.Errorf("cannot unmarshal PeerRecord to nil receiver")
}
defer func() { catch.HandlePanic(recover(), &err, "libp2p peer record unmarshal") }()
var msg pb.PeerRecord
err = proto.Unmarshal(bytes, &msg)
if err != nil {
return err
}
rPtr, err := PeerRecordFromProtobuf(&msg)
if err != nil {
return err
}
*r = *rPtr
return nil
}
// MarshalRecord serializes a PeerRecord to a byte slice.
// This method is called automatically when constructing a routing.Envelope
// using Seal or PeerRecord.Sign.
func (r *PeerRecord) MarshalRecord() (res []byte, err error) {
defer func() { catch.HandlePanic(recover(), &err, "libp2p peer record marshal") }()
msg, err := r.ToProtobuf()
if err != nil {
return nil, err
}
return proto.Marshal(msg)
}
// Equal returns true if the other PeerRecord is identical to this one.
func (r *PeerRecord) Equal(other *PeerRecord) bool {
if other == nil {
return r == nil
}
if r.PeerID != other.PeerID {
return false
}
if r.Seq != other.Seq {
return false
}
if len(r.Addrs) != len(other.Addrs) {
return false
}
for i := range r.Addrs {
if !r.Addrs[i].Equal(other.Addrs[i]) {
return false
}
}
return true
}
// ToProtobuf returns the equivalent Protocol Buffer struct object of a PeerRecord.
func (r *PeerRecord) ToProtobuf() (*pb.PeerRecord, error) {
idBytes, err := r.PeerID.MarshalBinary()
if err != nil {
return nil, err
}
return &pb.PeerRecord{
PeerId: idBytes,
Addresses: addrsToProtobuf(r.Addrs),
Seq: r.Seq,
}, nil
}
func addrsFromProtobuf(addrs []*pb.PeerRecord_AddressInfo) []ma.Multiaddr {
out := make([]ma.Multiaddr, 0, len(addrs))
for _, addr := range addrs {
a, err := ma.NewMultiaddrBytes(addr.Multiaddr)
if err != nil {
continue
}
out = append(out, a)
}
return out
}
func addrsToProtobuf(addrs []ma.Multiaddr) []*pb.PeerRecord_AddressInfo {
out := make([]*pb.PeerRecord_AddressInfo, 0, len(addrs))
for _, addr := range addrs {
out = append(out, &pb.PeerRecord_AddressInfo{Multiaddr: addr.Bytes()})
}
return out
}