first commit

pkg/address/address.go

@@ -0,0 +1,85 @@
+package address
+
+import (
+	"bytes"
+	"encoding/hex"
+	"errors"
+
+	"gitlab.33.cn/chat/dtalk/pkg/address/base58"
+	"gitlab.33.cn/chat/dtalk/pkg/address/crypto"
+)
+
+//Address 地址
+type Address struct {
+	Version  byte
+	Hash160  [20]byte // For a stealth address: it's HASH160
+	Checksum []byte   // Unused for a stealth address
+	Pubkey   []byte   // Unused for a stealth address
+	Enc58str string
+}
+
+//SetBytes 设置地址的bytes
+func (a *Address) SetBytes(b []byte) {
+	copy(a.Hash160[:], b)
+}
+
+func (a *Address) String() string {
+	if a.Enc58str == "" {
+		var ad [25]byte
+		ad[0] = a.Version
+		copy(ad[1:21], a.Hash160[:])
+		if a.Checksum == nil {
+			sh := crypto.Sha2Sum(ad[0:21])
+			a.Checksum = make([]byte, 4)
+			copy(a.Checksum, sh[:4])
+		}
+		copy(ad[21:25], a.Checksum[:])
+		a.Enc58str = base58.Encode(ad[:])
+	}
+	return a.Enc58str
+}
+
+//NormalVer 普通地址的版本号
+const NormalVer byte = 0
+
+func PublicKeyToAddress(version byte, in []byte) string {
+	a := new(Address)
+	a.Pubkey = make([]byte, len(in))
+	copy(a.Pubkey[:], in[:])
+	a.Version = version
+	a.SetBytes(crypto.Rimp160(in))
+	return a.String()
+}
+
+//CheckAddress 检查地址
+func CheckAddress(ver byte, addr string) (e error) {
+	dec := base58.Decode(addr)
+	if dec == nil {
+		e = errors.New("Cannot decode b58 string '" + addr + "'")
+		return
+	}
+	if len(dec) < 25 {
+		e = errors.New("Address too short " + hex.EncodeToString(dec))
+		return
+	}
+	//version 的错误优先
+	if dec[0] != ver {
+		e = ErrCheckVersion
+		return
+	}
+	//需要兼容以前的错误(以前的错误，是一种特殊的情况)
+	if len(dec) == 25 {
+		sh := crypto.Sha2Sum(dec[0:21])
+		if !bytes.Equal(sh[:4], dec[21:25]) {
+			e = ErrCheckChecksum
+			return
+		}
+	}
+	var cksum [4]byte
+	copy(cksum[:], dec[len(dec)-4:])
+	//新的错误: 这个错误用一种新的错误标记
+	if crypto.Checksum(dec[:len(dec)-4]) != cksum {
+		e = ErrAddressChecksum
+	}
+	return e
+}