diff --git a/dagger.go b/dagger.go new file mode 100644 index 0000000000..750a781b04 --- /dev/null +++ b/dagger.go @@ -0,0 +1,110 @@ +package main + +import ( + "math/big" + "fmt" + "math/rand" + "time" + "github.com/obscuren/sha3" +) + +type Dagger struct { + hash *big.Int + xn *big.Int +} + +func (dag *Dagger) Search(diff *big.Int) *big.Int { + dag.hash = big.NewInt(0) + + obj := BigPow(2, 256) + obj = obj.Div(obj, diff) + + fmt.Println("diff", diff, "< objective", obj) + + r := rand.New(rand.NewSource(time.Now().UnixNano())) + rnd := big.NewInt(r.Int63()) + fmt.Println("init rnd =", rnd) + + for i := 0; i < 1000; i++ { + if dag.Eval(rnd).Cmp(obj) < 0 { + fmt.Println("Found result! i = ", i) + return rnd + } + + rnd = rnd.Add(rnd, big.NewInt(1)) + } + + return big.NewInt(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.NewKeccak224() + sha.Reset() + d := sha3.NewKeccak224() + 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(d.Sum(nil)) + pk := b.Uint64() & ((1 << ((L - 1) * 3)) - 1) + sha.Write(dag.Node(L - 1, pk).Bytes()) + } + + ret.SetBytes(sha.Sum(nil)) + + return ret +} + +func (dag *Dagger) Eval(N *big.Int) *big.Int { + pow := BigPow(2, 26) + dag.xn = N.Div(N, pow) + + sha := sha3.NewKeccak224() + sha.Reset() + ret := new(big.Int) + + doneChan := make(chan bool, 3) + + for k := 0; k < 4; k++ { + go func(_k int) { + d := sha3.NewKeccak224() + 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(d.Sum(nil)) + pk := (b.Uint64() & 0x1ffffff) + + sha.Write(dag.Node(9, pk).Bytes()) + doneChan <- true + }(k) + } + + for k := 0; k < 4; k++ { + <- doneChan + } + + return ret.SetBytes(sha.Sum(nil)) +}