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
|
// Copyright 2014 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
package dagger
import (
"hash"
"math/big"
"math/rand"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto/sha3"
"github.com/ethereum/go-ethereum/logger"
)
var powlogger = logger.NewLogger("POW")
type Dagger struct {
hash *big.Int
xn *big.Int
}
var Found bool
func (dag *Dagger) Find(obj *big.Int, resChan chan int64) {
r := rand.New(rand.NewSource(time.Now().UnixNano()))
for i := 0; i < 1000; i++ {
rnd := r.Int63()
res := dag.Eval(big.NewInt(rnd))
powlogger.Infof("rnd %v\nres %v\nobj %v\n", rnd, res, obj)
if res.Cmp(obj) < 0 {
// Post back result on the channel
resChan <- rnd
// Notify other threads we've found a valid nonce
Found = true
}
// Break out if found
if Found {
break
}
}
resChan <- 0
}
func (dag *Dagger) Search(hash, diff *big.Int) (uint64, []byte) {
// TODO fix multi threading. Somehow it results in the wrong nonce
amountOfRoutines := 1
dag.hash = hash
obj := common.BigPow(2, 256)
obj = obj.Div(obj, diff)
Found = false
resChan := make(chan int64, 3)
var res int64
for k := 0; k < amountOfRoutines; k++ {
go dag.Find(obj, resChan)
// Wait for each go routine to finish
}
for k := 0; k < amountOfRoutines; k++ {
// Get the result from the channel. 0 = quit
if r := <-resChan; r != 0 {
res = r
}
}
return uint64(res), nil
}
func (dag *Dagger) Verify(hash, diff, nonce *big.Int) bool {
dag.hash = hash
obj := common.BigPow(2, 256)
obj = obj.Div(obj, diff)
return dag.Eval(nonce).Cmp(obj) < 0
}
func DaggerVerify(hash, diff, nonce *big.Int) bool {
dagger := &Dagger{}
dagger.hash = hash
obj := common.BigPow(2, 256)
obj = obj.Div(obj, diff)
return dagger.Eval(nonce).Cmp(obj) < 0
}
func (dag *Dagger) Node(L uint64, i uint64) *big.Int {
if L == i {
return dag.hash
}
var m *big.Int
if L == 9 {
m = big.NewInt(16)
} else {
m = big.NewInt(3)
}
sha := sha3.NewKeccak256()
sha.Reset()
d := sha3.NewKeccak256()
b := new(big.Int)
ret := new(big.Int)
for k := 0; k < int(m.Uint64()); k++ {
d.Reset()
d.Write(dag.hash.Bytes())
d.Write(dag.xn.Bytes())
d.Write(big.NewInt(int64(L)).Bytes())
d.Write(big.NewInt(int64(i)).Bytes())
d.Write(big.NewInt(int64(k)).Bytes())
b.SetBytes(Sum(d))
pk := b.Uint64() & ((1 << ((L - 1) * 3)) - 1)
sha.Write(dag.Node(L-1, pk).Bytes())
}
ret.SetBytes(Sum(sha))
return ret
}
func Sum(sha hash.Hash) []byte {
//in := make([]byte, 32)
return sha.Sum(nil)
}
func (dag *Dagger) Eval(N *big.Int) *big.Int {
pow := common.BigPow(2, 26)
dag.xn = pow.Div(N, pow)
sha := sha3.NewKeccak256()
sha.Reset()
ret := new(big.Int)
for k := 0; k < 4; k++ {
d := sha3.NewKeccak256()
b := new(big.Int)
d.Reset()
d.Write(dag.hash.Bytes())
d.Write(dag.xn.Bytes())
d.Write(N.Bytes())
d.Write(big.NewInt(int64(k)).Bytes())
b.SetBytes(Sum(d))
pk := (b.Uint64() & 0x1ffffff)
sha.Write(dag.Node(9, pk).Bytes())
}
return ret.SetBytes(Sum(sha))
}
|
