init: v1.0.0

mac/mac.go

@@ -0,0 +1,110 @@
+// package mac is the the implement of Message Authentication Code.
+// Includes cbcmac and hmac.
+//
+// 一般实际应用中我们只使用两种MAC：
+// 1) CBCMac, 实际上是使用全0的iv对原文进行CBC加密的最后一个分组。其中原文由调用者进行补位(padding)，输出
+// 为128比特；
+// 2) HMac_SM3, HMac对key和输出tag长度并没有限定 ，但一般key不能太小(< 80 bits), tag也不能小于80比特，
+// 并且tag长度不超过SM3杂凑值长度，即256比特。
+// 注：hmac可以使用标准库的方式：crypto/hmac.New(SM3.New, key).
+// 本package只是对crypto/hmac的包装.
+package mac
+
+import (
+	crypto_hmac "crypto/hmac"
+	"crypto/sha256"
+	"errors"
+	"hash"
+
+	"xdx.jelly/xgcl/identifier"
+	"xdx.jelly/xgcl/mac/cbcmac"
+	"xdx.jelly/xgcl/mac/hmac"
+	"xdx.jelly/xgcl/sm/sm1"
+	"xdx.jelly/xgcl/sm/sm3"
+	"xdx.jelly/xgcl/sm/sm4"
+)
+
+/*
+MAC is the interface for MACs (Message Authentication Codes).
+This interface should be used for authentication only, and not for other purposes
+(for example, it should not be used to generate pseudorandom bytes).
+
+MAC is "easy to use, hard to mistake".
+
+PS: The interface is from "Tink"
+*/
+type MAC interface {
+
+	// ComputeMAC computes message authentication code (MAC) for code data.
+	ComputeMAC(data []byte) ([]byte, error)
+
+	// Verify returns nil if mac is a correct authentication code (MAC) for data,
+	// otherwise it returns an error.
+	VerifyMAC(mac, data []byte) error
+}
+
+// NewHMacSm3 is a simple wrapper of hmac.NewHMAC
+// key 16- bytes
+// tagSize 10-32
+//
+// !Deprecated. Use NewMac instead.
+func NewHMacSm3(key []byte, tagSize uint32) (MAC, error) {
+	return hmac.NewHMAC("SM3", key, tagSize)
+}
+
+type MacType uint32
+
+const (
+	HMAC_SM3    = MacType(identifier.SGDSM3)
+	HMAC_SHA256 = MacType(identifier.SGDSHA256)
+	CBCMAC_SM1  = MacType(identifier.SGDSM1Mac)
+	CBCMAC_SM4  = MacType(identifier.SGDSM4Mac)
+)
+
+// NewMac returns a MAC interface, which is easy to use, hard to mistake.
+func NewMac(tpe MacType, key []byte) (MAC, error) {
+	switch tpe {
+	case HMAC_SM3:
+		return hmac.NewHMAC("SM3", key, sm3.Size)
+	case HMAC_SHA256:
+		return hmac.NewHMAC("SHA256", key, sha256.Size)
+	case CBCMAC_SM1:
+		b, err := sm1.NewCipher(key)
+		if err != nil {
+			return nil, err
+		}
+		return cbcmac.New(b)
+	case CBCMAC_SM4:
+		b, err := sm4.NewCipher(key)
+		if err != nil {
+			return nil, err
+		}
+		return cbcmac.New(b)
+	default:
+		return nil, errors.New("Unsurported mac type.")
+	}
+}
+
+// Return a hash.Hash interface, for multiple messages.
+func NewMacHash(tpe MacType, key []byte) (hash.Hash, error) {
+	switch tpe {
+	case HMAC_SM3:
+		return crypto_hmac.New(sm3.New, key), nil
+	case HMAC_SHA256:
+		return crypto_hmac.New(sha256.New, key), nil
+	// case CBCMAC_SM1:
+	// 	b, err := sm1.NewCipher(key)
+	// 	if err != nil {
+	// 		return nil, err
+	// 	}
+	// 	return cbcmac.New(b)
+	// case CBCMAC_SM4:
+	// 	b, err := sm4.NewCipher(key)
+	// 	if err != nil {
+	// 		return nil, err
+	// 	}
+	// 	return cbcmac.New(b)
+	default:
+		return nil, errors.New("Unsurported mac type.")
+	}
+}