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
|
// Copyright (C) 2019-2021 Algorand, Inc.
// This file is part of go-algorand
//
// go-algorand is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// go-algorand is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with go-algorand. If not, see <https://www.gnu.org/licenses/>.
package compactcert
import (
"github.com/algorand/go-algorand/crypto"
"github.com/algorand/go-algorand/data/basics"
"github.com/algorand/go-algorand/protocol"
)
// Params defines common parameters for the verifier and builder.
type Params struct {
Msg crypto.Hashable // Message to be cerified
ProvenWeight uint64 // Weight threshold proven by the certificate
SigRound basics.Round // Ephemeral signature round to expect
SecKQ uint64 // Security parameter (k+q) from analysis document
}
// A Participant corresponds to an account whose AccountData.Status
// is Online, and for which the expected sigRound satisfies
// AccountData.VoteFirstValid <= sigRound <= AccountData.VoteLastValid.
//
// In the Algorand ledger, it is possible for multiple accounts to have
// the same PK. Thus, the PK is not necessarily unique among Participants.
// However, each account will produce a unique Participant struct, to avoid
// potential DoS attacks where one account claims to have the same VoteID PK
// as another account.
type Participant struct {
_struct struct{} `codec:",omitempty,omitemptyarray"`
// PK is AccountData.VoteID.
PK crypto.OneTimeSignatureVerifier `codec:"p"`
// Weight is AccountData.MicroAlgos.
Weight uint64 `codec:"w"`
// KeyDilution is AccountData.KeyDilution() with the protocol for sigRound
// as expected by the Builder.
KeyDilution uint64 `codec:"d"`
}
// ToBeHashed implements the crypto.Hashable interface.
func (p Participant) ToBeHashed() (protocol.HashID, []byte) {
return protocol.CompactCertPart, protocol.Encode(&p)
}
// CompactOneTimeSignature is crypto.OneTimeSignature with omitempty
type CompactOneTimeSignature struct {
_struct struct{} `codec:",omitempty,omitemptyarray"`
crypto.OneTimeSignature
}
// A sigslotCommit is a single slot in the sigs array that forms the certificate.
type sigslotCommit struct {
_struct struct{} `codec:",omitempty,omitemptyarray"`
// Sig is a signature by the participant on the expected message.
Sig CompactOneTimeSignature `codec:"s"`
// L is the total weight of signatures in lower-numbered slots.
// This is initialized once the builder has collected a sufficient
// number of signatures.
L uint64 `codec:"l"`
}
func (ssc sigslotCommit) ToBeHashed() (protocol.HashID, []byte) {
return protocol.CompactCertSig, protocol.Encode(&ssc)
}
// Reveal is a single array position revealed as part of a compact
// certificate. It reveals an element of the signature array and
// the corresponding element of the participants array.
type Reveal struct {
_struct struct{} `codec:",omitempty,omitemptyarray"`
SigSlot sigslotCommit `codec:"s"`
Part Participant `codec:"p"`
}
// MaxReveals is a bound on allocation and on numReveals to limit log computation
const MaxReveals = 1024
// MaxProofDigests is a bound on allocation on number of proofs
const MaxProofDigests = 20 * MaxReveals
// Cert represents a compact certificate.
type Cert struct {
_struct struct{} `codec:",omitempty,omitemptyarray"`
SigCommit crypto.Digest `codec:"c"`
SignedWeight uint64 `codec:"w"`
SigProofs []crypto.Digest `codec:"S,allocbound=MaxProofDigests"`
PartProofs []crypto.Digest `codec:"P,allocbound=MaxProofDigests"`
// Reveals is a sparse map from the position being revealed
// to the corresponding elements from the sigs and participants
// arrays.
Reveals map[uint64]Reveal `codec:"r,allocbound=MaxReveals"`
}
// SortUint64 implements sorting by uint64 keys for
// canonical encoding of maps in msgpack format.
type SortUint64 = basics.SortUint64
|
