解密获取接收明文

utils/btls/bleHandler.js

@@ -267,18 +267,18 @@ class BLEHandler {
         // 校验帧头帧尾
         if (arrbf[0] != 0x89 || arrbf[1] != 0x89) {
          console.log('不是该设备返回的包')
-         return false
+         return [0];
         }        
          if (packetLen < 14) {
              console.log("包长太短，不是该设备返回的包");
-             return false;
+             return [0];
          }        
         
          let dataLength = ((arrbf[10] << 8) & 0xff00) + (arrbf[11] & 0x00ff);
          if (dataLength != (packetLen - 13)) {
              let calLen = packetLen - 13;
              console.log("✘ 数据长度错误: "  +  dataLength + " is not " + calLen);
-             return false;
+             return [0];
          }
          //校验包
          let check = arrbf[0];
@@ -286,10 +286,25 @@ class BLEHandler {
              check ^= arrbf[i];
              if (check != arrbf[packetLen - 1]) {
                  console.log("crc校验错误，请重发." + check);
-                 return false;
+                 return [0];
              }
+			 
+		        //数据解密
+        key = arrbf[3];
+		let  data_offset = 12;
+		
+		let result = new Uint8Array(dataLength)
+        for (let i = 0; i < dataLength; i++) {
+			result[i] = arrbf[i + data_offset];
+            result[i] = (result[i] ^ (key ^ ((byte) i)));
+            result[i] += (dataLength - i) ^ key;
+        }
+			 
          console.log('✔ 数据校验成功，接收完整！ packet= ' + arrbf)
-         return true       
+		 
+		 console.log('解密明文 result= ' + result)
+		 
+         return result;      
     }
 
 }