forked from prysmaticlabs/prysm
-
Notifications
You must be signed in to change notification settings - Fork 1
/
attester.go
196 lines (173 loc) · 7.18 KB
/
attester.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
package validator
import (
"context"
ptypes "github.com/gogo/protobuf/types"
ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
"github.com/prysmaticlabs/go-ssz"
"github.com/prysmaticlabs/prysm/beacon-chain/cache"
"github.com/prysmaticlabs/prysm/beacon-chain/core/feed"
"github.com/prysmaticlabs/prysm/beacon-chain/core/feed/operation"
"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
"github.com/prysmaticlabs/prysm/beacon-chain/core/state"
stateTrie "github.com/prysmaticlabs/prysm/beacon-chain/state"
"github.com/prysmaticlabs/prysm/shared/bls"
"github.com/prysmaticlabs/prysm/shared/bytesutil"
"github.com/prysmaticlabs/prysm/shared/featureconfig"
"github.com/prysmaticlabs/prysm/shared/params"
"go.opencensus.io/trace"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/status"
)
const msgInvalidAttestationRequest = "Attestation request must be within current or previous epoch"
// GetAttestationData requests that the beacon node produce an attestation data object,
// which the validator acting as an attester will then sign.
func (vs *Server) GetAttestationData(ctx context.Context, req *ethpb.AttestationDataRequest) (*ethpb.AttestationData, error) {
ctx, span := trace.StartSpan(ctx, "AttesterServer.RequestAttestation")
defer span.End()
span.AddAttributes(
trace.Int64Attribute("slot", int64(req.Slot)),
trace.Int64Attribute("committeeIndex", int64(req.CommitteeIndex)),
)
if vs.SyncChecker.Syncing() {
return nil, status.Errorf(codes.Unavailable, "Syncing to latest head, not ready to respond")
}
currentEpoch := helpers.SlotToEpoch(vs.GenesisTimeFetcher.CurrentSlot())
if currentEpoch > 0 && currentEpoch-1 != helpers.SlotToEpoch(req.Slot) && currentEpoch != helpers.SlotToEpoch(req.Slot) {
return nil, status.Error(codes.InvalidArgument, msgInvalidAttestationRequest)
}
res, err := vs.AttestationCache.Get(ctx, req)
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not retrieve data from attestation cache: %v", err)
}
if res != nil {
return res, nil
}
if err := vs.AttestationCache.MarkInProgress(req); err != nil {
if err == cache.ErrAlreadyInProgress {
res, err := vs.AttestationCache.Get(ctx, req)
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not retrieve data from attestation cache: %v", err)
}
if res == nil {
return nil, status.Error(codes.DataLoss, "A request was in progress and resolved to nil")
}
return res, nil
}
return nil, status.Errorf(codes.Internal, "Could not mark attestation as in-progress: %v", err)
}
defer func() {
if err := vs.AttestationCache.MarkNotInProgress(req); err != nil {
log.WithError(err).Error("Failed to mark cache not in progress")
}
}()
headState, err := vs.HeadFetcher.HeadState(ctx)
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not retrieve head state: %v", err)
}
headRoot, err := vs.HeadFetcher.HeadRoot(ctx)
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not retrieve head root: %v", err)
}
// In the case that we receive an attestation request after a newer state/block has been processed.
if headState.Slot() > req.Slot {
headRoot, err = helpers.BlockRootAtSlot(headState, req.Slot)
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not get historical head root: %v", err)
}
if featureconfig.Get().NewStateMgmt {
headState, err = vs.StateGen.StateByRoot(ctx, bytesutil.ToBytes32(headRoot))
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not get historical head state: %v", err)
}
} else {
headState, err = vs.BeaconDB.State(ctx, bytesutil.ToBytes32(headRoot))
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not get historical head state: %v", err)
}
}
}
if headState == nil {
return nil, status.Error(codes.Internal, "Failed to lookup parent state from head.")
}
if helpers.CurrentEpoch(headState) < helpers.SlotToEpoch(req.Slot) {
headState, err = state.ProcessSlots(ctx, headState, helpers.StartSlot(helpers.SlotToEpoch(req.Slot)))
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not process slots up to %d: %v", req.Slot, err)
}
}
targetEpoch := helpers.CurrentEpoch(headState)
epochStartSlot := helpers.StartSlot(targetEpoch)
targetRoot := make([]byte, 32)
if epochStartSlot == headState.Slot() {
targetRoot = headRoot[:]
} else {
targetRoot, err = helpers.BlockRootAtSlot(headState, epochStartSlot)
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not get target block for slot %d: %v", epochStartSlot, err)
}
if bytesutil.ToBytes32(targetRoot) == params.BeaconConfig().ZeroHash {
targetRoot = headRoot
}
}
res = ðpb.AttestationData{
Slot: req.Slot,
CommitteeIndex: req.CommitteeIndex,
BeaconBlockRoot: headRoot[:],
Source: headState.CurrentJustifiedCheckpoint(),
Target: ðpb.Checkpoint{
Epoch: targetEpoch,
Root: targetRoot,
},
}
if err := vs.AttestationCache.Put(ctx, req, res); err != nil {
return nil, status.Errorf(codes.Internal, "Could not store attestation data in cache: %v", err)
}
return res, nil
}
// ProposeAttestation is a function called by an attester to vote
// on a block via an attestation object as defined in the Ethereum Serenity specification.
func (vs *Server) ProposeAttestation(ctx context.Context, att *ethpb.Attestation) (*ethpb.AttestResponse, error) {
if _, err := bls.SignatureFromBytes(att.Signature); err != nil {
return nil, status.Error(codes.InvalidArgument, "Incorrect attestation signature")
}
root, err := ssz.HashTreeRoot(att.Data)
if err != nil {
return nil, status.Errorf(codes.Internal, "Could not tree hash attestation: %v", err)
}
// Broadcast the unaggregated attestation on a feed to notify other services in the beacon node
// of a received unaggregated attestation.
vs.OperationNotifier.OperationFeed().Send(&feed.Event{
Type: operation.UnaggregatedAttReceived,
Data: &operation.UnAggregatedAttReceivedData{
Attestation: att,
},
})
// Broadcast the new attestation to the network.
if err := vs.P2P.Broadcast(ctx, att); err != nil {
return nil, status.Errorf(codes.Internal, "Could not broadcast attestation: %v", err)
}
go func() {
ctx = trace.NewContext(context.Background(), trace.FromContext(ctx))
attCopy := stateTrie.CopyAttestation(att)
if err := vs.AttPool.SaveUnaggregatedAttestation(attCopy); err != nil {
log.WithError(err).Error("Could not handle attestation in operations service")
return
}
}()
return ðpb.AttestResponse{
AttestationDataRoot: root[:],
}, nil
}
// SubscribeCommitteeSubnets subscribes to the committee ID subnet given subscribe request.
func (vs *Server) SubscribeCommitteeSubnets(ctx context.Context, req *ethpb.CommitteeSubnetsSubscribeRequest) (*ptypes.Empty, error) {
if len(req.Slots) != len(req.CommitteeIds) && len(req.CommitteeIds) != len(req.IsAggregator) {
return nil, status.Error(codes.InvalidArgument, "request fields are not the same length")
}
for i := 0; i < len(req.Slots); i++ {
cache.CommitteeIDs.AddAttesterCommiteeID(req.Slots[i], req.CommitteeIds[i])
if req.IsAggregator[i] {
cache.CommitteeIDs.AddAggregatorCommiteeID(req.Slots[i], req.CommitteeIds[i])
}
}
return &ptypes.Empty{}, nil
}