forked from ava-labs/avalanchego
-
Notifications
You must be signed in to change notification settings - Fork 4
/
majority.go
109 lines (93 loc) · 2.8 KB
/
majority.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
// Copyright (C) 2019-2024, Ava Labs, Inc. All rights reserved.
// See the file LICENSE for licensing terms.
package bootstrapper
import (
"context"
"go.uber.org/zap"
"golang.org/x/exp/maps"
"github.com/MetalBlockchain/metalgo/ids"
"github.com/MetalBlockchain/metalgo/utils/logging"
"github.com/MetalBlockchain/metalgo/utils/math"
"github.com/MetalBlockchain/metalgo/utils/set"
)
var _ Poll = (*Majority)(nil)
// Majority implements the bootstrapping poll to filter the initial set of
// potentially accaptable blocks into a set of accepted blocks to sync to.
//
// Once the last accepted blocks have been fetched from the initial set of
// peers, the set of blocks are sent to all peers. Each peer is expected to
// filter the provided blocks and report which of them they consider accepted.
// If a majority of the peers report that a block is accepted, then the node
// will consider that block to be accepted by the network. This assumes that a
// majority of the network is correct. If a majority of the network is
// malicious, the node may accept an incorrect block.
type Majority struct {
requests
log logging.Logger
nodeWeights map[ids.NodeID]uint64
// received maps the blockID to the total sum of weight that has reported
// that block as accepted.
received map[ids.ID]uint64
accepted []ids.ID
}
func NewMajority(
log logging.Logger,
nodeWeights map[ids.NodeID]uint64,
maxOutstanding int,
) *Majority {
return &Majority{
requests: requests{
maxOutstanding: maxOutstanding,
pendingSend: set.Of(maps.Keys(nodeWeights)...),
},
log: log,
nodeWeights: nodeWeights,
received: make(map[ids.ID]uint64),
}
}
func (m *Majority) RecordOpinion(_ context.Context, nodeID ids.NodeID, blkIDs set.Set[ids.ID]) error {
if !m.recordResponse(nodeID) {
// The chain router should have already dropped unexpected messages.
m.log.Error("received unexpected opinion",
zap.String("pollType", "majority"),
zap.Stringer("nodeID", nodeID),
zap.Reflect("blkIDs", blkIDs),
)
return nil
}
weight := m.nodeWeights[nodeID]
for blkID := range blkIDs {
newWeight, err := math.Add64(m.received[blkID], weight)
if err != nil {
return err
}
m.received[blkID] = newWeight
}
if !m.finished() {
return nil
}
var (
totalWeight uint64
err error
)
for _, weight := range m.nodeWeights {
totalWeight, err = math.Add64(totalWeight, weight)
if err != nil {
return err
}
}
requiredWeight := totalWeight/2 + 1
for blkID, weight := range m.received {
if weight >= requiredWeight {
m.accepted = append(m.accepted, blkID)
}
}
m.log.Debug("finalized bootstrapping poll",
zap.String("pollType", "majority"),
zap.Stringers("accepted", m.accepted),
)
return nil
}
func (m *Majority) Result(context.Context) ([]ids.ID, bool) {
return m.accepted, m.finished()
}