Merge pull request #1 from dqx0/dev

digital sig

Author: dqx0

blockchain/blockchain.go

@@ -192,7 +192,7 @@ func (chain *BlockChain) Next() *Block {
 	return block
 }
 
-func (chain *BlockChain) FindUnspentTransactions(address string) []Transaction {
+func (chain *BlockChain) FindUnspentTransactions(pubKeyHash []byte) []Transaction {
 	var unspentTxs []Transaction
 
 	spentTXOs := make(map[string][]int)
@@ -212,13 +212,13 @@ func (chain *BlockChain) FindUnspentTransactions(address string) []Transaction {
 						}
 					}
 				}
-				if out.CanBeUnlocked(address) {
+				if out.IsLockedWithKey(pubKeyHash) {
 					unspentTxs = append(unspentTxs, *tx)
 				}
 			}
 			if !tx.IsCoinbase() {
 				for _, in := range tx.Inputs {
-					if in.CanUnlock(address) {
+					if in.UsesKey(pubKeyHash) {
 						inTxID := hex.EncodeToString(in.ID)
 						spentTXOs[inTxID] = append(spentTXOs[inTxID], in.Out)
 					}
@@ -232,13 +232,13 @@ func (chain *BlockChain) FindUnspentTransactions(address string) []Transaction {
 	return unspentTxs
 }
 
-func (chain *BlockChain) FindUTXO(address string) []TxOutput {
+func (chain *BlockChain) FindUTXO(pubKeyHash []byte) []TxOutput {
 	var UTXOs []TxOutput
-	unspentTransactions := chain.FindUnspentTransactions(address)
+	unspentTransactions := chain.FindUnspentTransactions(pubKeyHash)
 
 	for _, tx := range unspentTransactions {
 		for _, out := range tx.Outputs {
-			if out.CanBeUnlocked(address) {
+			if out.IsLockedWithKey(pubKeyHash) {
 				UTXOs = append(UTXOs, out)
 			}
 		}
@@ -256,17 +256,17 @@ func (chain *BlockChain) FindUTXO(address string) []TxOutput {
 // returns:
 //   - int: 見つかった未使用出力の合計金額
 //   - map[string][]int: トランザクションIDをキーとし、使用可能な出力インデックスの配列を値とするマップ
-func (chain *BlockChain) FindSpendableOutputs(address string, amount int) (int, map[string][]int) {
+func (chain *BlockChain) FindSpendableOutputs(pubKeyHash []byte, amount int) (int, map[string][]int) {
 	unspentOutputs := make(map[string][]int)
-	unspentTxs := chain.FindUnspentTransactions(address)
+	unspentTxs := chain.FindUnspentTransactions(pubKeyHash)
 	accumulated := 0
 
 Work:
 	for _, tx := range unspentTxs {
 		txID := hex.EncodeToString(tx.ID)
 
 		for outIdx, out := range tx.Outputs {
-			if out.CanBeUnlocked(address) && accumulated < amount {
+			if out.IsLockedWithKey(pubKeyHash) && accumulated < amount {
 				accumulated += out.Value
 				unspentOutputs[txID] = append(unspentOutputs[txID], outIdx)
 

blockchain/transaction.go

@@ -7,6 +7,8 @@ import (
 	"encoding/hex"
 	"fmt"
 	"log"
+
+	"github.com/dqx0/blockchain/wallet"
 )
 
 type Transaction struct {
@@ -15,6 +17,29 @@ type Transaction struct {
 	Outputs []TxOutput // 出力トランザクションのリスト
 }
 
+func (tx *Transaction) Hash() []byte {
+	var hash [32]byte
+
+	txCopy := *tx
+	txCopy.ID = []byte{}
+
+	hash = sha256.Sum256(txCopy.Serialize())
+
+	return hash[:]
+}
+
+func (tx Transaction) Serialize() []byte {
+	var encoded bytes.Buffer
+
+	enc := gob.NewEncoder(&encoded)
+	err := enc.Encode(tx)
+	if err != nil {
+		log.Panic(err)
+	}
+
+	return encoded.Bytes()
+}
+
 // トランザクションのハッシュIDを生成
 // トランザクションの内容をgobでエンコードし、SHA-256ハッシュを計算
 func (tx *Transaction) SetID() {
@@ -40,10 +65,10 @@ func CoinbaseTx(to, data string) *Transaction {
 	}
 
 	// コインベーストランザクションは過去の参照を持たない特殊なインプット
-	txin := TxInput{[]byte{}, -1, data}
+	txin := TxInput{[]byte{}, -1, nil, []byte(data)}
 	// 報酬として100コインを設定
-	txout := TxOutput{100, to}
-	tx := Transaction{nil, []TxInput{txin}, []TxOutput{txout}}
+	txout := NewTXOutput(100, to)
+	tx := Transaction{nil, []TxInput{txin}, []TxOutput{*txout}}
 	tx.SetID()
 
 	return &tx
@@ -59,8 +84,13 @@ func CoinbaseTx(to, data string) *Transaction {
 func NewTransaction(from, to string, amount int, bc *BlockChain) *Transaction {
 	var inputs []TxInput
 	var outputs []TxOutput
+
+	wallets, err := wallet.CreateWallets()
+	Handle(err)
+	w := wallets.GetWallet(from)
+	pubKeyHash := wallet.PublicKeyHash(w.PublicKey)
 	// 利用可能なUTXOを検索
-	acc, validOutputs := bc.FindSpendableOutputs(from, amount)
+	acc, validOutputs := bc.FindSpendableOutputs(pubKeyHash, amount)
 
 	if acc < amount {
 		log.Panic("Error: Not enough funds")
@@ -72,16 +102,16 @@ func NewTransaction(from, to string, amount int, bc *BlockChain) *Transaction {
 		Handle(err)
 
 		for _, out := range outs {
-			input := TxInput{txID, out, from}
+			input := TxInput{txID, out, nil, w.PublicKey}
 			inputs = append(inputs, input)
 		}
 	}
 
 	// 出力トランザクションの作成
-	outputs = append(outputs, TxOutput{amount, to})
+	outputs = append(outputs, *NewTXOutput(amount, to))
 	// おつりがある場合は送金元に返す
 	if acc > amount {
-		outputs = append(outputs, TxOutput{acc - amount, from})
+		outputs = append(outputs, *NewTXOutput(acc-amount, from))
 	}
 
 	tx := Transaction{nil, inputs, outputs}

blockchain/tx.go

@@ -1,22 +1,42 @@
 package blockchain
 
+import (
+	"bytes"
+
+	"github.com/dqx0/blockchain/wallet"
+)
+
 type TxOutput struct {
-	Value  int    // 送金額
-	PubKey string // 受取人の公開鍵
+	Value      int    // 送金額
+	PubKeyHash []byte // 受取人の公開鍵
 }
 
 type TxInput struct {
-	ID  []byte // 参照する過去のトランザクションID
-	Out int    // 参照する出力インデックス
-	Sig string // 送信者の署名
+	ID     []byte // 参照する過去のトランザクションID
+	Out    int    // 参照する出力インデックス
+	Sig    []byte // 送信者の署名
+	PubKey []byte // 送信者の公開鍵
+}
+
+func (in *TxInput) UsesKey(pubKeyHash []byte) bool {
+	lockingHash := wallet.PublicKeyHash(in.PubKey)
+
+	return bytes.Compare(lockingHash, pubKeyHash) == 0
+}
+
+func (out *TxOutput) Lock(address []byte) {
+	pubKeyHash := wallet.Base58Decode(address)
+	pubKeyHash = pubKeyHash[1 : len(pubKeyHash)-4]
+	out.PubKeyHash = pubKeyHash
 }
 
-// 指定されたデータで入力トランザクションがアンロック可能か検証
-func (in *TxInput) CanUnlock(data string) bool {
-	return in.Sig == data
+func (out *TxOutput) IsLockedWithKey(pubKeyHash []byte) bool {
+	return bytes.Compare(out.PubKeyHash, pubKeyHash) == 0
 }
 
-// 指定されたデータで出力トランザクションが使用可能か検証
-func (out *TxOutput) CanBeUnlocked(data string) bool {
-	return out.PubKey == data
+func NewTXOutput(value int, address string) *TxOutput {
+	txo := &TxOutput{value, nil}
+	txo.Lock([]byte(address))
+
+	return txo
 }

cmd/cmd.go

@@ -76,7 +76,9 @@ func (cli *CommandLine) getBalance(address string) {
 	defer chain.Database.Close()
 
 	balance := 0
-	UTXOs := chain.FindUTXO(address)
+	pubKeyHash := wallet.Base58Decode([]byte(address))
+	pubKeyHash = pubKeyHash[1 : len(pubKeyHash)-4]
+	UTXOs := chain.FindUTXO(pubKeyHash)
 
 	for _, out := range UTXOs {
 		balance += out.Value