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<h1 class="entry-title"><a href="https://kingx.me/Details-in-FastJson-RCE.html" rel="bookmark" title="FastJson反序列化漏洞利用的三个细节 - TemplatesImpl的利用链">FastJson反序列化漏洞利用的三个细节 - TemplatesImpl的利用链</a></h1>
<h2><span class="entry-date date published"><time datetime="2018-07-09T00:00:00-04:00">July 09, 2018, KINGX</time></span></h2>
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<span class="entry-tags" style="color:red;font-size:13px;margin-bottom: 0px;">「声明：本博客中涉及到的相关漏洞均为官方已经公开并修复的漏洞，涉及到的安全技术也仅用于企业安全建设和安全对抗研究。本文仅限业内技术研究与讨论，严禁用于非法用途，否则产生的一切后果自行承担。」</span>
<h1 id="0-前言">0. 前言</h1>
<p>记录在FastJson反序列化RCE漏洞分析和利用时的一些细节问题。</p>
<h1 id="1-templatesimpl的利用链">1. TemplatesImpl的利用链</h1>
<h2 id="关于-parse-和-parseobject">关于 parse 和 parseObject</h2>
<p>FastJson中的 parse() 和 parseObject()方法都可以用来将JSON字符串反序列化成Java对象，parseObject() 本质上也是调用 parse() 进行反序列化的。但是 parseObject() 会额外的将Java对象转为 JSONObject对象，即 JSON.toJSON()。所以进行反序列化时的细节区别在于，parse() 会识别并调用目标类的 setter 方法及某些特定条件的 getter 方法，而 parseObject() 由于多执行了 JSON.toJSON(obj)，所以在处理过程中会调用反序列化目标类的所有 setter 和 getter 方法。parseObject() 的源代码如下：</p>
<div class="language-java highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="kd">public</span> <span class="kd">static</span> <span class="n">JSONObject</span> <span class="nf">parseObject</span><span class="o">(</span><span class="n">String</span> <span class="n">text</span><span class="o">)</span> <span class="o">{</span>
<span class="n">Object</span> <span class="n">obj</span> <span class="o">=</span> <span class="n">parse</span><span class="o">(</span><span class="n">text</span><span class="o">);</span>
<span class="k">if</span> <span class="o">(</span><span class="n">obj</span> <span class="k">instanceof</span> <span class="n">JSONObject</span><span class="o">)</span> <span class="o">{</span>
<span class="k">return</span> <span class="o">(</span><span class="n">JSONObject</span><span class="o">)</span> <span class="n">obj</span><span class="o">;</span>
<span class="o">}</span>
<span class="k">return</span> <span class="o">(</span><span class="n">JSONObject</span><span class="o">)</span> <span class="n">JSON</span><span class="o">.</span><span class="na">toJSON</span><span class="o">(</span><span class="n">obj</span><span class="o">);</span>
<span class="o">}</span>
</code></pre></div></div>
<p>举个简单的例子：</p>
<div class="language-java highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="kd">public</span> <span class="kd">class</span> <span class="nc">FastJsonTest</span> <span class="o">{</span>
<span class="kd">public</span> <span class="n">String</span> <span class="n">name</span><span class="o">;</span>
<span class="kd">public</span> <span class="n">String</span> <span class="n">age</span><span class="o">;</span>
<span class="kd">public</span> <span class="nf">FastJsonTest</span><span class="o">()</span> <span class="kd">throws</span> <span class="n">IOException</span><span class="o">{</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="kt">void</span> <span class="nf">setName</span><span class="o">(</span><span class="n">String</span> <span class="n">test</span><span class="o">)</span> <span class="o">{</span>
<span class="n">System</span><span class="o">.</span><span class="na">out</span><span class="o">.</span><span class="na">println</span><span class="o">(</span><span class="s">"name setter called"</span><span class="o">);</span>
<span class="k">this</span><span class="o">.</span><span class="na">name</span> <span class="o">=</span> <span class="n">test</span><span class="o">;</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="n">String</span> <span class="nf">getName</span><span class="o">()</span> <span class="o">{</span>
<span class="n">System</span><span class="o">.</span><span class="na">out</span><span class="o">.</span><span class="na">println</span><span class="o">(</span><span class="s">"name getter called"</span><span class="o">);</span>
<span class="k">return</span> <span class="k">this</span><span class="o">.</span><span class="na">name</span><span class="o">;</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="n">String</span> <span class="nf">getAge</span><span class="o">(){</span>
<span class="n">System</span><span class="o">.</span><span class="na">out</span><span class="o">.</span><span class="na">println</span><span class="o">(</span><span class="s">"age getter called"</span><span class="o">);</span>
<span class="k">return</span> <span class="k">this</span><span class="o">.</span><span class="na">age</span><span class="o">;</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="kd">static</span> <span class="kt">void</span> <span class="nf">main</span><span class="o">(</span><span class="n">String</span><span class="o">[]</span> <span class="n">args</span><span class="o">)</span> <span class="o">{</span>
<span class="n">Object</span> <span class="n">obj</span> <span class="o">=</span> <span class="n">JSON</span><span class="o">.</span><span class="na">parse</span><span class="o">(</span><span class="s">"{\"@type\":\"fastjsontest.FastJsonTest\",\"name\":\"thisisname\", \"age\":\"thisisage\"}"</span><span class="o">);</span>
<span class="n">System</span><span class="o">.</span><span class="na">out</span><span class="o">.</span><span class="na">println</span><span class="o">(</span><span class="n">obj</span><span class="o">);</span>
<span class="n">Object</span> <span class="n">obj2</span> <span class="o">=</span> <span class="n">JSON</span><span class="o">.</span><span class="na">parseObject</span><span class="o">(</span><span class="s">"{\"@type\":\"fastjsontest.FastJsonTest\",\"name\":\"thisisname\", \"age\":\"thisisage\"}"</span><span class="o">);</span>
<span class="n">System</span><span class="o">.</span><span class="na">out</span><span class="o">.</span><span class="na">println</span><span class="o">(</span><span class="n">obj2</span><span class="o">);</span>
<span class="o">}</span>
<span class="o">}</span>
</code></pre></div></div>
<p>上述代码运行后可以看到，执行parse() 时，只有 setName() 会被调用。执行parseObject() 时，setName()、getAge()、getName() 均会被调用。</p>
<h2 id="为什么会触发getoutputproperties">为什么会触发getOutputProperties()</h2>
<p>感觉上 parse() 进行反序列化创建Java类应该只会调用 setter 方法进行成员变量赋值才对，会什么会触发TemplatesImpl类中的 getOutputProperties() 方法呢？</p>
<p>另外 _outputProperties 成员变量和 getOutputProperties() 明明差了一个<code class="highlighter-rouge">_</code>字符，是怎么被 FastJson 关联上的?</p>
<p>如上一小节所述，parse() 进行反序列化时其实会调用某些特定的 getter 方法进行字段解析，而 TemplatesImpl类中的 getOutputProperties() 方法恰好满足这一条件。</p>
<p>FastJson反序列化到Java类时主要逻辑如下：</p>
<ol>
<li>获取并保存目标Java类中的成员变量、setter、getter。</li>
<li>解析JSON字符串，对字段逐个处理，调用相应的setter、getter进行变量赋值。</li>
</ol>
<p>我们先看第一步，这里由 JavaBeanInfo.build() 进行处理，FastJson会创建一个filedList数组，用来保存目标Java类的成员变量以及相应的setter或getter方法信息，供后续反序列化字段时调用。</p>
<p>filedList大致结构如下：</p>
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>[
{
name:"outputProperties",
method:{
clazz:{},
name:"getOutputProperties",
returnType:{},
...
}
}
]
</code></pre></div></div>
<p>FastJson并不是直接反射获取目标Java类的成员变量的，而是会对setter、getter、成员变量分别进行处理，智能提取出成员变量信息。逻辑如下：</p>
<ol>
<li>识别setter方法名，并根据setter方法名提取出成员变量名。如：识别出setAge()方法，FastJson会提取出age变量名并插入filedList数组。</li>
<li>通过clazz.getFields()获取成员变量。</li>
<li>识别getter方法名，并根据getter方法名提取出成员变量名。</li>
</ol>
<p>可以看到在 JavaBeanInfo.build() 中，有一段代码会对getter方法进行判断，在某些特殊条件下，会从getter方法中提取出成员变量名并附加到filedList数组中。而TemplatesImpl类中的 getOutputProperties() 正好满足这个特定条件。getter方法的处理代码为：</p>
<div class="language-java highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">JavaBeanInfo</span><span class="o">.</span><span class="na">java</span>
<span class="kd">public</span> <span class="kd">static</span> <span class="n">JavaBeanInfo</span> <span class="nf">build</span><span class="o">(</span><span class="n">Class</span><span class="o"><?></span> <span class="n">clazz</span><span class="o">,</span> <span class="n">Type</span> <span class="n">type</span><span class="o">,</span> <span class="n">PropertyNamingStrategy</span> <span class="n">propertyNamingStrategy</span><span class="o">)</span> <span class="o">{</span>
<span class="o">...</span>
<span class="k">for</span> <span class="o">(</span><span class="n">Method</span> <span class="n">method</span> <span class="o">:</span> <span class="n">clazz</span><span class="o">.</span><span class="na">getMethods</span><span class="o">())</span> <span class="o">{</span> <span class="c1">// getter methods</span>
<span class="n">String</span> <span class="n">methodName</span> <span class="o">=</span> <span class="n">method</span><span class="o">.</span><span class="na">getName</span><span class="o">();</span>
<span class="k">if</span> <span class="o">(</span><span class="n">methodName</span><span class="o">.</span><span class="na">length</span><span class="o">()</span> <span class="o"><</span> <span class="mi">4</span><span class="o">)</span> <span class="o">{</span>
<span class="k">continue</span><span class="o">;</span>
<span class="o">}</span>
<span class="k">if</span> <span class="o">(</span><span class="n">Modifier</span><span class="o">.</span><span class="na">isStatic</span><span class="o">(</span><span class="n">method</span><span class="o">.</span><span class="na">getModifiers</span><span class="o">()))</span> <span class="o">{</span>
<span class="k">continue</span><span class="o">;</span>
<span class="o">}</span>
<span class="k">if</span> <span class="o">(</span><span class="n">methodName</span><span class="o">.</span><span class="na">startsWith</span><span class="o">(</span><span class="s">"get"</span><span class="o">)</span> <span class="o">&&</span> <span class="n">Character</span><span class="o">.</span><span class="na">isUpperCase</span><span class="o">(</span><span class="n">methodName</span><span class="o">.</span><span class="na">charAt</span><span class="o">(</span><span class="mi">3</span><span class="o">)))</span> <span class="o">{</span>
<span class="k">if</span> <span class="o">(</span><span class="n">method</span><span class="o">.</span><span class="na">getParameterTypes</span><span class="o">().</span><span class="na">length</span> <span class="o">!=</span> <span class="mi">0</span><span class="o">)</span> <span class="o">{</span>
<span class="k">continue</span><span class="o">;</span>
<span class="o">}</span>
<span class="c1">// 关键条件</span>
<span class="k">if</span> <span class="o">(</span><span class="n">Collection</span><span class="o">.</span><span class="na">class</span><span class="o">.</span><span class="na">isAssignableFrom</span><span class="o">(</span><span class="n">method</span><span class="o">.</span><span class="na">getReturnType</span><span class="o">())</span> <span class="c1">//</span>
<span class="o">||</span> <span class="n">Map</span><span class="o">.</span><span class="na">class</span><span class="o">.</span><span class="na">isAssignableFrom</span><span class="o">(</span><span class="n">method</span><span class="o">.</span><span class="na">getReturnType</span><span class="o">())</span> <span class="c1">//</span>
<span class="o">||</span> <span class="n">AtomicBoolean</span><span class="o">.</span><span class="na">class</span> <span class="o">==</span> <span class="n">method</span><span class="o">.</span><span class="na">getReturnType</span><span class="o">()</span> <span class="c1">//</span>
<span class="o">||</span> <span class="n">AtomicInteger</span><span class="o">.</span><span class="na">class</span> <span class="o">==</span> <span class="n">method</span><span class="o">.</span><span class="na">getReturnType</span><span class="o">()</span> <span class="c1">//</span>
<span class="o">||</span> <span class="n">AtomicLong</span><span class="o">.</span><span class="na">class</span> <span class="o">==</span> <span class="n">method</span><span class="o">.</span><span class="na">getReturnType</span><span class="o">()</span> <span class="c1">//</span>
<span class="o">)</span> <span class="o">{</span>
<span class="n">String</span> <span class="n">propertyName</span><span class="o">;</span>
<span class="n">JSONField</span> <span class="n">annotation</span> <span class="o">=</span> <span class="n">method</span><span class="o">.</span><span class="na">getAnnotation</span><span class="o">(</span><span class="n">JSONField</span><span class="o">.</span><span class="na">class</span><span class="o">);</span>
<span class="k">if</span> <span class="o">(</span><span class="n">annotation</span> <span class="o">!=</span> <span class="kc">null</span> <span class="o">&&</span> <span class="n">annotation</span><span class="o">.</span><span class="na">deserialize</span><span class="o">())</span> <span class="o">{</span>
<span class="k">continue</span><span class="o">;</span>
<span class="o">}</span>
<span class="k">if</span> <span class="o">(</span><span class="n">annotation</span> <span class="o">!=</span> <span class="kc">null</span> <span class="o">&&</span> <span class="n">annotation</span><span class="o">.</span><span class="na">name</span><span class="o">().</span><span class="na">length</span><span class="o">()</span> <span class="o">></span> <span class="mi">0</span><span class="o">)</span> <span class="o">{</span>
<span class="n">propertyName</span> <span class="o">=</span> <span class="n">annotation</span><span class="o">.</span><span class="na">name</span><span class="o">();</span>
<span class="o">}</span> <span class="k">else</span> <span class="o">{</span>
<span class="n">propertyName</span> <span class="o">=</span> <span class="n">Character</span><span class="o">.</span><span class="na">toLowerCase</span><span class="o">(</span><span class="n">methodName</span><span class="o">.</span><span class="na">charAt</span><span class="o">(</span><span class="mi">3</span><span class="o">))</span> <span class="o">+</span> <span class="n">methodName</span><span class="o">.</span><span class="na">substring</span><span class="o">(</span><span class="mi">4</span><span class="o">);</span>
<span class="o">}</span>
<span class="n">FieldInfo</span> <span class="n">fieldInfo</span> <span class="o">=</span> <span class="n">getField</span><span class="o">(</span><span class="n">fieldList</span><span class="o">,</span> <span class="n">propertyName</span><span class="o">);</span>
<span class="k">if</span> <span class="o">(</span><span class="n">fieldInfo</span> <span class="o">!=</span> <span class="kc">null</span><span class="o">)</span> <span class="o">{</span>
<span class="k">continue</span><span class="o">;</span>
<span class="o">}</span>
<span class="k">if</span> <span class="o">(</span><span class="n">propertyNamingStrategy</span> <span class="o">!=</span> <span class="kc">null</span><span class="o">)</span> <span class="o">{</span>
<span class="n">propertyName</span> <span class="o">=</span> <span class="n">propertyNamingStrategy</span><span class="o">.</span><span class="na">translate</span><span class="o">(</span><span class="n">propertyName</span><span class="o">);</span>
<span class="o">}</span>
<span class="n">add</span><span class="o">(</span><span class="n">fieldList</span><span class="o">,</span> <span class="k">new</span> <span class="n">FieldInfo</span><span class="o">(</span><span class="n">propertyName</span><span class="o">,</span> <span class="n">method</span><span class="o">,</span> <span class="kc">null</span><span class="o">,</span> <span class="n">clazz</span><span class="o">,</span> <span class="n">type</span><span class="o">,</span> <span class="mi">0</span><span class="o">,</span> <span class="mi">0</span><span class="o">,</span> <span class="mi">0</span><span class="o">,</span> <span class="n">annotation</span><span class="o">,</span> <span class="kc">null</span><span class="o">,</span> <span class="kc">null</span><span class="o">));</span>
<span class="o">}</span>
<span class="o">}</span>
<span class="o">}</span>
<span class="o">...</span>
<span class="o">}</span>
</code></pre></div></div>
<p>接下来，FastJson会语义分析JSON字符串。根据字段key，调用filedList数组中存储的相应方法进行变量初始化赋值。具体逻辑在 parseField() 中实现：</p>
<div class="language-java highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">JavaBeanDeserializer</span>
<span class="kd">public</span> <span class="kt">boolean</span> <span class="nf">parseField</span><span class="o">(</span><span class="n">DefaultJSONParser</span> <span class="n">parser</span><span class="o">,</span> <span class="n">String</span> <span class="n">key</span><span class="o">,</span> <span class="n">Object</span> <span class="n">object</span><span class="o">,</span> <span class="n">Type</span> <span class="n">objectType</span><span class="o">,</span>
<span class="n">Map</span><span class="o"><</span><span class="n">String</span><span class="o">,</span> <span class="n">Object</span><span class="o">></span> <span class="n">fieldValues</span><span class="o">)</span> <span class="o">{</span>
<span class="n">JSONLexer</span> <span class="n">lexer</span> <span class="o">=</span> <span class="n">parser</span><span class="o">.</span><span class="na">lexer</span><span class="o">;</span> <span class="c1">// xxx</span>
<span class="n">FieldDeserializer</span> <span class="n">fieldDeserializer</span> <span class="o">=</span> <span class="n">smartMatch</span><span class="o">(</span><span class="n">key</span><span class="o">);</span>
<span class="o">...</span>
<span class="k">return</span> <span class="kc">true</span><span class="o">;</span>
<span class="o">}</span>
</code></pre></div></div>
<p>这里调用了一个神奇的 smartMatch() 方法，smartMatch()时会替换掉字段key中的<code class="highlighter-rouge">_</code>，从而 _outputProperties 和 getOutputProperties() 可以成功关联上。</p>
<div class="language-java highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">JavaBeanDeserializer</span>
<span class="kd">public</span> <span class="n">FieldDeserializer</span> <span class="nf">smartMatch</span><span class="o">(</span><span class="n">String</span> <span class="n">key</span><span class="o">)</span> <span class="o">{</span>
<span class="k">if</span> <span class="o">(</span><span class="n">fieldDeserializer</span> <span class="o">==</span> <span class="kc">null</span><span class="o">)</span> <span class="o">{</span>
<span class="kt">boolean</span> <span class="n">snakeOrkebab</span> <span class="o">=</span> <span class="kc">false</span><span class="o">;</span>
<span class="n">String</span> <span class="n">key2</span> <span class="o">=</span> <span class="kc">null</span><span class="o">;</span>
<span class="k">for</span> <span class="o">(</span><span class="kt">int</span> <span class="n">i</span> <span class="o">=</span> <span class="mi">0</span><span class="o">;</span> <span class="n">i</span> <span class="o"><</span> <span class="n">key</span><span class="o">.</span><span class="na">length</span><span class="o">();</span> <span class="o">++</span><span class="n">i</span><span class="o">)</span> <span class="o">{</span>
<span class="kt">char</span> <span class="n">ch</span> <span class="o">=</span> <span class="n">key</span><span class="o">.</span><span class="na">charAt</span><span class="o">(</span><span class="n">i</span><span class="o">);</span>
<span class="k">if</span> <span class="o">(</span><span class="n">ch</span> <span class="o">==</span> <span class="sc">'_'</span><span class="o">)</span> <span class="o">{</span>
<span class="n">snakeOrkebab</span> <span class="o">=</span> <span class="kc">true</span><span class="o">;</span>
<span class="n">key2</span> <span class="o">=</span> <span class="n">key</span><span class="o">.</span><span class="na">replaceAll</span><span class="o">(</span><span class="s">"_"</span><span class="o">,</span> <span class="s">""</span><span class="o">);</span>
<span class="k">break</span><span class="o">;</span>
<span class="o">}</span> <span class="k">else</span> <span class="k">if</span> <span class="o">(</span><span class="n">ch</span> <span class="o">==</span> <span class="sc">'-'</span><span class="o">)</span> <span class="o">{</span>
<span class="n">snakeOrkebab</span> <span class="o">=</span> <span class="kc">true</span><span class="o">;</span>
<span class="n">key2</span> <span class="o">=</span> <span class="n">key</span><span class="o">.</span><span class="na">replaceAll</span><span class="o">(</span><span class="s">"-"</span><span class="o">,</span> <span class="s">""</span><span class="o">);</span>
<span class="k">break</span><span class="o">;</span>
<span class="o">}</span>
<span class="o">}</span>
<span class="k">if</span> <span class="o">(</span><span class="n">snakeOrkebab</span><span class="o">)</span> <span class="o">{</span>
<span class="n">fieldDeserializer</span> <span class="o">=</span> <span class="n">getFieldDeserializer</span><span class="o">(</span><span class="n">key2</span><span class="o">);</span>
<span class="k">if</span> <span class="o">(</span><span class="n">fieldDeserializer</span> <span class="o">==</span> <span class="kc">null</span><span class="o">)</span> <span class="o">{</span>
<span class="k">for</span> <span class="o">(</span><span class="n">FieldDeserializer</span> <span class="n">fieldDeser</span> <span class="o">:</span> <span class="n">sortedFieldDeserializers</span><span class="o">)</span> <span class="o">{</span>
<span class="k">if</span> <span class="o">(</span><span class="n">fieldDeser</span><span class="o">.</span><span class="na">fieldInfo</span><span class="o">.</span><span class="na">name</span><span class="o">.</span><span class="na">equalsIgnoreCase</span><span class="o">(</span><span class="n">key2</span><span class="o">))</span> <span class="o">{</span>
<span class="n">fieldDeserializer</span> <span class="o">=</span> <span class="n">fieldDeser</span><span class="o">;</span>
<span class="k">break</span><span class="o">;</span>
<span class="o">}</span>
<span class="o">}</span>
<span class="o">}</span>
<span class="o">}</span>
<span class="o">}</span>
</code></pre></div></div>
<h2 id="为什么需要对_bytecodes进行base64编码">为什么需要对_bytecodes进行Base64编码</h2>
<p>细心的你可以发现，PoC中的 _bytecodes 字段是经过Base64编码的。为什么要这么做呢？
分析FastJson对JSON字符串的解析过程，原来FastJson提取byte[]数组字段值时会进行Base64解码，所以我们构造payload时需要对 _bytecodes 进行Base64处理。FastJson的处理代码如下：</p>
<div class="language-java highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">ObjectArrayCodec</span>
<span class="kd">public</span> <span class="o"><</span><span class="n">T</span><span class="o">></span> <span class="n">T</span> <span class="nf">deserialze</span><span class="o">(</span><span class="n">DefaultJSONParser</span> <span class="n">parser</span><span class="o">,</span> <span class="n">Type</span> <span class="n">type</span><span class="o">,</span> <span class="n">Object</span> <span class="n">fieldName</span><span class="o">)</span> <span class="o">{</span>
<span class="kd">final</span> <span class="n">JSONLexer</span> <span class="n">lexer</span> <span class="o">=</span> <span class="n">parser</span><span class="o">.</span><span class="na">lexer</span><span class="o">;</span>
<span class="c1">// ......省略部分代码</span>
<span class="k">if</span> <span class="o">(</span><span class="n">lexer</span><span class="o">.</span><span class="na">token</span><span class="o">()</span> <span class="o">==</span> <span class="n">JSONToken</span><span class="o">.</span><span class="na">LITERAL_STRING</span><span class="o">)</span> <span class="o">{</span>
<span class="kt">byte</span><span class="o">[]</span> <span class="n">bytes</span> <span class="o">=</span> <span class="n">lexer</span><span class="o">.</span><span class="na">bytesValue</span><span class="o">();</span> <span class="c1">// ... 在这里解析byte数组值</span>
<span class="n">lexer</span><span class="o">.</span><span class="na">nextToken</span><span class="o">(</span><span class="n">JSONToken</span><span class="o">.</span><span class="na">COMMA</span><span class="o">);</span>
<span class="k">return</span> <span class="o">(</span><span class="n">T</span><span class="o">)</span> <span class="n">bytes</span><span class="o">;</span>
<span class="o">}</span>
<span class="c1">// 接着调用JSONScanner.bytesValue()</span>
<span class="n">JSONScanner</span>
<span class="kd">public</span> <span class="kt">byte</span><span class="o">[]</span> <span class="nf">bytesValue</span><span class="o">()</span> <span class="o">{</span>
<span class="k">return</span> <span class="n">IOUtils</span><span class="o">.</span><span class="na">decodeBase64</span><span class="o">(</span><span class="n">text</span><span class="o">,</span> <span class="n">np</span> <span class="o">+</span> <span class="mi">1</span><span class="o">,</span> <span class="n">sp</span><span class="o">);</span>
<span class="o">}</span>
</code></pre></div></div>
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