Merge branch 'bugfix/ble_enhanced_security_v5.3' into 'release/v5.3'

Update BluFi document (v5.3)

See merge request espressif/esp-idf!41762

docs/en/api-guides/ble/blufi.rst

@@ -481,6 +481,16 @@ The data to be encrypted and decrypted must be in the same length. The IV8 is an
 
 This function is used to compute CheckSum and return a value of CheckSum. BluFi uses the returned value to compare the CheckSum of the frame.
 
+5. Implementing Stronger Security
+
+The default encryption/decryption logic in this example is intended for demonstration purposes only.
+
+If you require a higher level of security, it is recommended to implement your own encryption, decryption, authentication, and checksum algorithms by customizing the security callbacks in the BluFi framework.
+
+.. code-block:: c
+
+   esp_err_t esp_blufi_register_callbacks(esp_blufi_callbacks_t *callbacks)
+
 GATT Related Instructions
 ----------------------------
 

docs/zh_CN/api-guides/ble/blufi.rst

@@ -481,6 +481,17 @@ BluFi 会在调用完 Negotiate_data_handler 后，发送 Negotiate_data_handler
 
 该函数用来进行校验，返回值为校验的值。BluFi 会使用该函数返回值与帧的校验值进行比较。
 
+5. 实现更强的安全性
+
+本示例中默认的加密/解密逻辑仅用于演示目的。
+
+如果需要更高等级的安全性，建议通过自定义 BluFi 框架中的安全回调函数，实现您自己的加密、解密、认证以及校验算法。
+
+.. code-block:: c
+
+   esp_err_t esp_blufi_register_callbacks(esp_blufi_callbacks_t *callbacks)
+
+
 GATT 相关说明
 -------------