从崩溃的选课系统，论为什么更安全的 HTTPS 协议没有被全面采用

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前言","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"上一篇文章详细讲解了 HTTP 的相关原理，我们已经了解到了 HTTP 具有非常优秀和方便的一面，然而，HTTP 并非一个安全的协议。大家平常浏览网页的时候应该也能注意到，使用 HTTP 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的不安全性体现在很多方面，例举如下：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"通信使用明文（不加密），内容可能被","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"窃听","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"不验证通信对方的身份，因此有可能遭遇","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"伪装","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"无法证明报文的完整性，所以有可能被","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"篡改","attrs":{}}]}],"attrs":{}}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"当然，这些问题不仅在 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的请求和响应不会对通信方进行确认","attrs":{}},{"type":"text","text":"，也就是说任何人都可以发起请求，而服务器对请求者来者不拒，只要接收到请求，就会返回一个响应。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/6f/6fe62071a42c25a9344d9b38b62ab5f0.png","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"显然，正是由于 HTTP 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APP，但是，在你下载的过程当中，攻击者攻击了这个网站，你正在传输的文件内容被篡改成了其他文件，而在这个过程中，你是完全察觉不到的。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"像这样的在请求或响应在传输途中，遭受攻击者拦截并篡改内容的攻击称为","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"中间人攻击","attrs":{}},{"type":"text","text":"（Main-in-the-Middle attack, 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