fadd

internal/shared/fadada/sign.go

@@ -0,0 +1,57 @@
+package fadada
+
+import (
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/hex"
+	"sort"
+	"strings"
+)
+
+const (
+	signTypeHMACSHA256 = "HMAC-SHA256"
+	apiSubVersion      = "5.1"
+)
+
+// SignByMap 法大大 HMAC-SHA256 签名（与官方 SDK 算法一致）
+// 1) 对 map key 字典序排序，拼接 key=value&...（跳过空值）
+// 2) signText = hex(SHA256(signContent))
+// 3) signKey  = HMAC-SHA256(timestamp, appSecret) 原始字节
+// 4) signature = lowercase(hex(HMAC-SHA256(signText, signKey)))
+func SignByMap(headMap map[string]string, timestamp, appSecret string) string {
+	signContent := sortMapForSign(headMap)
+	signText := sha256Hex(signContent)
+	secretSigning := hmacSHA256Bytes(timestamp, []byte(appSecret))
+	return strings.ToLower(hmacSHA256Hex(signText, secretSigning))
+}
+
+func sortMapForSign(headMap map[string]string) string {
+	keys := make([]string, 0, len(headMap))
+	for k := range headMap {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+
+	parts := make([]string, 0, len(keys))
+	for _, k := range keys {
+		if v := headMap[k]; v != "" {
+			parts = append(parts, k+"="+v)
+		}
+	}
+	return strings.Join(parts, "&")
+}
+
+func sha256Hex(src string) string {
+	sum := sha256.Sum256([]byte(src))
+	return hex.EncodeToString(sum[:])
+}
+
+func hmacSHA256Bytes(data string, secret []byte) []byte {
+	h := hmac.New(sha256.New, secret)
+	h.Write([]byte(data))
+	return h.Sum(nil)
+}
+
+func hmacSHA256Hex(data string, secret []byte) string {
+	return hex.EncodeToString(hmacSHA256Bytes(data, secret))
+}