实现地址 / go实现简易区块链 #6

比特币钱包中并不像普通帐户那样真的有钱，而是公私钥的集合。先来定义钱包（wallet）的结构：

type Wallet struct {
    PrivateKey ecdsa.PrivateKey
    PublicKey  []byte
}
type Wallets struct {
    Wallets map[string]*Wallet
}
func NewWallet() *Wallet {
    private, public := newKeyPair()
    wallet := Wallet{private, public}
    return &wallet
}
func newKeyPair() (ecdsa.PrivateKey, []byte) {
    curve := elliptic.P256()
    private, err := ecdsa.GenerateKey(curve, rand.Reader)
    pubKey := append(private.PublicKey.X.Bytes(), private.PublicKey.Y.Bytes()...)
    return *private, pubKey
}

可见钱包中除了密钥对，其它什么也没有。现在需要Wallets类型来维护这起集合。

//运算地址
func (w Wallet) GetAddress() []byte {
    pubKeyHash := HashPubKey(w.PublicKey)
    versionedPayload := append([]byte{version}, pubKeyHash...)
    checksum := checksum(versionedPayload)
    fullPayload := append(versionedPayload, checksum...)
    address := Base58Encode(fullPayload)
    return address
}

func HashPubKey(pubKey []byte) []byte {
    publicSHA256 := sha256.Sum256(pubKey)
    RIPEMD160Hasher := ripemd160.New()
    _, err := RIPEMD160Hasher.Write(publicSHA256[:])
    publicRIPEMD160 := RIPEMD160Hasher.Sum(nil)
    return publicRIPEMD160
}
func checksum(payload []byte) []byte {
    firstSHA := sha256.Sum256(payload)
    secondSHA := sha256.Sum256(firstSHA[:])
    return secondSHA[:addressChecksumLen]
}