添加文件: ymt_v3_generate/crypto.go

ymt_v3_generate/crypto.go

@@ -0,0 +1,223 @@
+package ymt_v3_generate
+
+import (
+	"bytes"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/sha256"
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// PKCS7Padding 填充
+func pkcs7Padding(data []byte, blockSize int) []byte {
+	padding := blockSize - len(data)%blockSize
+	padtext := bytes.Repeat([]byte{byte(padding)}, padding)
+	return append(data, padtext...)
+}
+
+// pkcs7UnPadding 去除填充
+func pkcs7UnPadding(data []byte) ([]byte, error) {
+	length := len(data)
+	if length == 0 {
+		return nil, errors.New("data is empty")
+	}
+	unpadding := int(data[length-1])
+	if unpadding > length || unpadding == 0 {
+		return nil, errors.New("invalid padding")
+	}
+	return data[:length-unpadding], nil
+}
+
+// aesECBEncrypt AES ECB 加密
+func aesECBEncrypt(plaintext []byte, key []byte) ([]byte, error) {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	blockSize := block.BlockSize()
+	plaintext = pkcs7Padding(plaintext, blockSize)
+	ciphertext := make([]byte, len(plaintext))
+	// ECB 模式：逐块加密
+	for start := 0; start < len(plaintext); start += blockSize {
+		block.Encrypt(ciphertext[start:start+blockSize], plaintext[start:start+blockSize])
+	}
+	return ciphertext, nil
+}
+
+// aesECBDecrypt AES ECB 解密
+func aesECBDecrypt(ciphertext []byte, key []byte) ([]byte, error) {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	blockSize := block.BlockSize()
+	if len(ciphertext)%blockSize != 0 {
+		return nil, errors.New("ciphertext is not a multiple of block size")
+	}
+	plaintext := make([]byte, len(ciphertext))
+	for start := 0; start < len(ciphertext); start += blockSize {
+		block.Decrypt(plaintext[start:start+blockSize], ciphertext[start:start+blockSize])
+	}
+	return pkcs7UnPadding(plaintext)
+}
+
+// EncryptPlaintext 加密明文（AES ECB），返回 base64 字符串
+func EncryptPlaintext(plaintext string, key []byte) (string, error) {
+	ciphertext, err := aesECBEncrypt([]byte(plaintext), key)
+	if err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(ciphertext), nil
+}
+
+// DecryptCiphertext 解密密文（base64 输入），返回明文字符串
+func DecryptCiphertext(ciphertextBase64 string, key []byte) (string, error) {
+	ciphertext, err := base64.StdEncoding.DecodeString(ciphertextBase64)
+	if err != nil {
+		return "", err
+	}
+	plaintext, err := aesECBDecrypt(ciphertext, key)
+	if err != nil {
+		return "", err
+	}
+	return string(plaintext), nil
+}
+
+// Sign 生成签名：appid + timestamp + ciphertext，使用 RSA 私钥签名，返回 base64 签名
+func Sign(appID, timestamp, ciphertext string, privateKey *rsa.PrivateKey) (string, error) {
+	data := appID + timestamp + ciphertext
+	hash := sha256.Sum256([]byte(data))
+	signature, err := rsa.SignPKCS1v15(rand.Reader, privateKey, crypto.SHA256, hash[:])
+	if err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(signature), nil
+}
+
+// VerifySign 验证签名
+func VerifySign(appID, timestamp, ciphertext, signBase64 string, publicKey *rsa.PublicKey) error {
+	data := appID + timestamp + ciphertext
+	hash := sha256.Sum256([]byte(data))
+	signature, err := base64.StdEncoding.DecodeString(signBase64)
+	if err != nil {
+		return err
+	}
+	return rsa.VerifyPKCS1v15(publicKey, crypto.SHA256, hash[:], signature)
+}
+
+// ParsePrivateKey 解析 PEM 格式的 RSA 私钥
+func ParsePrivateKey(pemStr string) (*rsa.PrivateKey, error) {
+	block, _ := pem.Decode([]byte(pemStr))
+	if block == nil {
+		return nil, errors.New("failed to parse PEM block containing private key")
+	}
+	// 尝试 PKCS1
+	key, err := x509.ParsePKCS1PrivateKey(block.Bytes)
+	if err == nil {
+		return key, nil
+	}
+	// 尝试 PKCS8
+	key8, err := x509.ParsePKCS8PrivateKey(block.Bytes)
+	if err == nil {
+		if rsaKey, ok := key8.(*rsa.PrivateKey); ok {
+			return rsaKey, nil
+		}
+		return nil, errors.New("parsed key is not RSA")
+	}
+	return nil, fmt.Errorf("failed to parse private key: %v", err)
+}
+
+// ParsePublicKey 解析 PEM 格式的 RSA 公钥
+func ParsePublicKey(pemStr string) (*rsa.PublicKey, error) {
+	block, _ := pem.Decode([]byte(pemStr))
+	if block == nil {
+		return nil, errors.New("failed to parse PEM block containing public key")
+	}
+	// 尝试 PKIX
+	key, err := x509.ParsePKIXPublicKey(block.Bytes)
+	if err == nil {
+		if rsaKey, ok := key.(*rsa.PublicKey); ok {
+			return rsaKey, nil
+		}
+		return nil, errors.New("parsed key is not RSA")
+	}
+	// 尝试 PKCS1
+	rsaKey, err := x509.ParsePKCS1PublicKey(block.Bytes)
+	if err == nil {
+		return rsaKey, nil
+	}
+	return nil, fmt.Errorf("failed to parse public key: %v", err)
+}
+
+// RemoveZeroValuesAndSort 将结构体转为 map，过滤零值，按键排序，返回 JSON 字符串
+func RemoveZeroValuesAndSort(v interface{}) (string, error) {
+	// 使用反射获取字段
+	val := reflect.ValueOf(v)
+	if val.Kind() == reflect.Ptr {
+		val = val.Elem()
+	}
+	if val.Kind() != reflect.Struct {
+		return "", errors.New("input must be a struct")
+	}
+	typ := val.Type()
+	m := make(map[string]interface{})
+	for i := 0; i < val.NumField(); i++ {
+		field := typ.Field(i)
+		jsonTag := field.Tag.Get("json")
+		if jsonTag == "" || jsonTag == "-" {
+			continue
+		}
+		// 处理 omitempty
+		name := strings.Split(jsonTag, ",")[0]
+		fieldVal := val.Field(i)
+		// 检查零值
+		if fieldVal.IsZero() {
+			continue
+		}
+		m[name] = fieldVal.Interface()
+	}
+	// 按键排序
+	keys := make([]string, 0, len(m))
+	for k := range m {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	// 构建 JSON
+	var buf bytes.Buffer
+	buf.WriteByte('{')
+	for i, k := range keys {
+		if i > 0 {
+			buf.WriteByte(',')
+		}
+		buf.WriteString(`"` + k + `":`)
+		// 简单序列化（仅支持基本类型）
+		v := m[k]
+		switch val := v.(type) {
+		case string:
+			buf.WriteString(`"` + val + `"`)
+		case int, int32, int64, uint, uint32, uint64:
+			fmt.Fprintf(&buf, "%d", val)
+		case float64:
+			fmt.Fprintf(&buf, "%v", val)
+		case bool:
+			fmt.Fprintf(&buf, "%t", val)
+		default:
+			// 使用 json.Marshal 处理复杂类型
+			b, err := json.Marshal(v)
+			if err != nil {
+				return "", err
+			}
+			buf.Write(b)
+		}
+	}
+	buf.WriteByte('}')
+	return buf.String(), nil
+}