A PHP operation class to obtain google chrome extension crx file information

This class implements obtaining the extended Appid from the crx file, obtaining the content of the manifest.json file, and converting the crx file into a general zip file

The code is as follows:

<?<span style="color: #000000;">php
</span><span style="color: #0000ff;">class</span> CrxParserException <span style="color: #0000ff;">extends</span> <span style="color: #0000ff;">Exception</span><span style="color: #000000;"> {

}

</span><span style="color: #008000;">/*</span><span style="color: #008000;">*
 * Chrome crx 解析器，用于获取扩展、皮肤ID
 *
 </span><span style="color: #008000;">*/</span>
<span style="color: #0000ff;">class</span><span style="color: #000000;"> CrxParser {
    </span><span style="color: #0000ff;">const</span> MAX_PUBLIC_KEY_SIZE = 65535<span style="color: #000000;">;
    </span><span style="color: #0000ff;">const</span> MAX_SIGNATURE_SIZE  = 65535<span style="color: #000000;">;
    </span><span style="color: #0000ff;">const</span> HEADER_MAGIC_PREFIX = 'Cr24'<span style="color: #000000;">;
    </span><span style="color: #0000ff;">const</span> CURRENT_VERSION     = 2<span style="color: #000000;">;

    </span><span style="color: #0000ff;">private</span> <span style="color: #800080;">$fp</span> = <span style="color: #0000ff;">null</span>; <span style="color: #008000;">//</span><span style="color: #008000;">文件指针</span>
    <span style="color: #0000ff;">private</span> <span style="color: #800080;">$filename</span> = ''; <span style="color: #008000;">//</span><span style="color: #008000;">文件路径</span>
    <span style="color: #0000ff;">private</span> <span style="color: #800080;">$_header</span> = <span style="color: #0000ff;">array</span>(); <span style="color: #008000;">//</span><span style="color: #008000;">crx 文件的头信息</span>

    <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> __construct(<span style="color: #800080;">$filename</span><span style="color: #000000;">){
        </span><span style="color: #800080;">$this</span>->parse(<span style="color: #800080;">$filename</span><span style="color: #000000;">);
    }

    </span><span style="color: #008000;">/*</span><span style="color: #008000;">*
     * 获取此应用的ID
     * @return string
     </span><span style="color: #008000;">*/</span>
    <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> getAppid() {
        </span><span style="color: #800080;">$hash</span> = hash('sha256',<span style="color: #800080;">$this</span>-><span style="color: #000000;">_key);
        </span><span style="color: #800080;">$hash</span> = <span style="color: #008080;">substr</span>(<span style="color: #800080;">$hash</span>,0,32<span style="color: #000000;">);

        </span><span style="color: #800080;">$length</span> = <span style="color: #008080;">strlen</span>(<span style="color: #800080;">$hash</span><span style="color: #000000;">);
        </span><span style="color: #800080;">$ascii_0</span> = <span style="color: #008080;">ord</span>('0'<span style="color: #000000;">);
        </span><span style="color: #800080;">$ascii_9</span> = <span style="color: #008080;">ord</span>('9'<span style="color: #000000;">);
        </span><span style="color: #800080;">$ascii_a</span> = <span style="color: #008080;">ord</span>('a'<span style="color: #000000;">);
        </span><span style="color: #800080;">$data</span> = ''<span style="color: #000000;">;
        </span><span style="color: #0000ff;">for</span>(<span style="color: #800080;">$i</span>=0;<span style="color: #800080;">$i</span><<span style="color: #800080;">$length</span>;<span style="color: #800080;">$i</span>++<span style="color: #000000;">) {
            </span><span style="color: #800080;">$c</span> = <span style="color: #008080;">ord</span>(<span style="color: #800080;">$hash</span>[<span style="color: #800080;">$i</span><span style="color: #000000;">]);

            </span><span style="color: #0000ff;">if</span>(<span style="color: #800080;">$c</span> >= <span style="color: #800080;">$ascii_0</span> && <span style="color: #800080;">$c</span> <= <span style="color: #800080;">$ascii_9</span><span style="color: #000000;">) {
                </span><span style="color: #800080;">$d</span> = <span style="color: #008080;">chr</span>(<span style="color: #800080;">$ascii_a</span> + <span style="color: #800080;">$c</span> - <span style="color: #800080;">$ascii_0</span><span style="color: #000000;">);
            } </span><span style="color: #0000ff;">else</span> <span style="color: #0000ff;">if</span>(<span style="color: #800080;">$c</span> >= <span style="color: #800080;">$ascii_a</span> && <span style="color: #800080;">$c</span> < <span style="color: #800080;">$ascii_a</span> + 6<span style="color: #000000;">) {
                </span><span style="color: #800080;">$d</span> = <span style="color: #008080;">chr</span>(<span style="color: #800080;">$ascii_a</span> + <span style="color: #800080;">$c</span> - <span style="color: #800080;">$ascii_a</span> + 10<span style="color: #000000;">);
            } </span><span style="color: #0000ff;">else</span><span style="color: #000000;"> {
                </span><span style="color: #800080;">$d</span> = 'a'<span style="color: #000000;">;
            }
            </span><span style="color: #800080;">$data</span> .= <span style="color: #800080;">$d</span><span style="color: #000000;">;
        }
        </span><span style="color: #0000ff;">return</span> <span style="color: #800080;">$data</span><span style="color: #000000;">;
    }

    </span><span style="color: #008000;">/*</span><span style="color: #008000;">*
     * 从crx文件中获取manifest.json文件的配置信息
     * @param unknown $zip_file
     * @return mixed[]
     </span><span style="color: #008000;">*/</span>
    <span style="color: #0000ff;">function</span> getConfig(<span style="color: #800080;">$key</span>=<span style="color: #0000ff;">null</span><span style="color: #000000;">){
        </span><span style="color: #800080;">$zip_file</span>=<span style="color: #008080;">tempnam</span>(<span style="color: #008080;">dirname</span>(<span style="color: #800080;">$this</span>->filename),'zip'<span style="color: #000000;">);
        </span><span style="color: #800080;">$manifest_arr</span>=<span style="color: #0000ff;">array</span><span style="color: #000000;">();
        </span><span style="color: #0000ff;">if</span>(<span style="color: #800080;">$this</span>->convertToZip(<span style="color: #800080;">$zip_file</span><span style="color: #000000;">)){
            </span><span style="color: #800080;">$zip</span>=zip_open(<span style="color: #800080;">$zip_file</span><span style="color: #000000;">);
            </span><span style="color: #0000ff;">if</span>(<span style="color: #008080;">is_resource</span>(<span style="color: #800080;">$zip</span><span style="color: #000000;">)){
                </span><span style="color: #0000ff;">while</span>(<span style="color: #800080;">$zip_entry</span>=zip_read(<span style="color: #800080;">$zip</span><span style="color: #000000;">)){
                    </span><span style="color: #800080;">$entry_name</span>=zip_entry_name(<span style="color: #800080;">$zip_entry</span><span style="color: #000000;">);
                    </span><span style="color: #0000ff;">if</span>(<span style="color: #008080;">preg_match</span>('/manifest\.json$/', <span style="color: #800080;">$entry_name</span><span style="color: #000000;">)){
                        </span><span style="color: #800080;">$content</span>=zip_entry_read(<span style="color: #800080;">$zip_entry</span>, zip_entry_filesize(<span style="color: #800080;">$zip_entry</span><span style="color: #000000;">));
                        </span><span style="color: #800080;">$content_j</span>=json_decode(<span style="color: #800080;">$content</span>, <span style="color: #0000ff;">true</span><span style="color: #000000;">);
                        </span><span style="color: #0000ff;">if</span>(!<span style="color: #0000ff;">empty</span>(<span style="color: #800080;">$content_j</span><span style="color: #000000;">)){
                            </span><span style="color: #800080;">$manifest_arr</span>=<span style="color: #800080;">$content_j</span><span style="color: #000000;">;
                        }
                    }
                }
            }
            zip_close(</span><span style="color: #800080;">$zip</span><span style="color: #000000;">);
            </span><span style="color: #008080;">unlink</span>(<span style="color: #800080;">$zip_file</span><span style="color: #000000;">);
        }
        </span><span style="color: #0000ff;">return</span> <span style="color: #008080;">is_null</span>(<span style="color: #800080;">$key</span>) ? <span style="color: #800080;">$manifest_arr</span> : <span style="color: #800080;">$manifest_arr</span>[<span style="color: #800080;">$key</span><span style="color: #000000;">];
    }

    </span><span style="color: #008000;">/*</span><span style="color: #008000;">*
     * 将文件转换为zip文件
     * @param unknown $target_path
     </span><span style="color: #008000;">*/</span>
    <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">function</span> convertToZip(<span style="color: #800080;">$target_path</span>=<span style="color: #0000ff;">null</span><span style="color: #000000;">){
        </span><span style="color: #800080;">$offset</span>=16+<span style="color: #800080;">$this</span>->_header['key_size']+<span style="color: #800080;">$this</span>->_header['sig_size'<span style="color: #000000;">];
        </span><span style="color: #800080;">$data</span>=<span style="color: #800080;">$this</span>->getContent(<span style="color: #800080;">$this</span>->filename,<span style="color: #800080;">$offset</span><span style="color: #000000;">);
        </span><span style="color: #0000ff;">return</span> !<span style="color: #008080;">is_null</span>(<span style="color: #800080;">$target_path</span>) ? <span style="color: #008080;">file_put_contents</span>(<span style="color: #800080;">$target_path</span>, <span style="color: #800080;">$data</span>) : <span style="color: #800080;">$data</span><span style="color: #000000;">;
    }

    </span><span style="color: #008000;">/*</span><span style="color: #008000;">*
     * 开始解析该 crx 文件
     </span><span style="color: #008000;">*/</span>
    <span style="color: #0000ff;">private</span> <span style="color: #0000ff;">function</span> parse(<span style="color: #800080;">$filename</span><span style="color: #000000;">) {
        </span><span style="color: #0000ff;">if</span>(<span style="color: #008080;">strpos</span>(<span style="color: #800080;">$filename</span>, '://')!==<span style="color: #0000ff;">false</span> && !<span style="color: #008080;">file_exists</span>(<span style="color: #800080;">$filename</span><span style="color: #000000;">)) {
            </span><span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> CrxParserException("parser init: crx file does not exisit"<span style="color: #000000;">);
        }
        </span><span style="color: #800080;">$this</span>->filename=<span style="color: #800080;">$filename</span><span style="color: #000000;">;
        </span><span style="color: #800080;">$this</span>->fp = <span style="color: #008080;">fopen</span>(<span style="color: #800080;">$filename</span>, 'r'<span style="color: #000000;">);
        </span><span style="color: #800080;">$this</span>->parse_header(); <span style="color: #008000;">//</span><span style="color: #008000;"> 解析头部信息</span>
        <span style="color: #800080;">$this</span>-><span style="color: #000000;">parse_key();
        </span><span style="color: #800080;">$this</span>-><span style="color: #000000;">parse_sig();
        </span><span style="color: #008080;">fclose</span>(<span style="color: #800080;">$this</span>-><span style="color: #000000;">fp);
    }

    </span><span style="color: #008000;">/*</span><span style="color: #008000;">*
     * 解析头部信息，并设置 $_header 数组
     * @throws CrxParserException 解析错误抛出异常
     </span><span style="color: #008000;">*/</span>
    <span style="color: #0000ff;">private</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> parse_header() {
        </span><span style="color: #800080;">$data</span> = <span style="color: #008080;">fread</span>(<span style="color: #800080;">$this</span>->fp, 16); <span style="color: #008000;">//</span><span style="color: #008000;"> HEADER 头信息有16个字节</span>
        <span style="color: #0000ff;">if</span>(<span style="color: #800080;">$data</span><span style="color: #000000;">) {
            </span><span style="color: #800080;">$data</span> = @<span style="color: #008080;">unpack</span>('C4prefix/Vversion/Vkey_size/Vsig_size',<span style="color: #800080;">$data</span><span style="color: #000000;">);
        }</span><span style="color: #0000ff;">else</span><span style="color: #000000;">{
            </span><span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> CrxParserException("header parse: error reading header"<span style="color: #000000;">);
        }
        </span><span style="color: #008000;">//</span><span style="color: #008000;"> 前四个字节拼合 prefix</span>
        <span style="color: #800080;">$data</span>['prefix'] = <span style="color: #008080;">chr</span>( <span style="color: #800080;">$data</span>['prefix1'] ).<span style="color: #008080;">chr</span>( <span style="color: #800080;">$data</span>['prefix2'] ).<span style="color: #008080;">chr</span>( <span style="color: #800080;">$data</span>['prefix3'] ).<span style="color: #008080;">chr</span>( <span style="color: #800080;">$data</span>['prefix4'<span style="color: #000000;">] );
        </span><span style="color: #0000ff;">unset</span>(<span style="color: #800080;">$data</span>['prefix1'],<span style="color: #800080;">$data</span>['prefix2'],<span style="color: #800080;">$data</span>['prefix3'],<span style="color: #800080;">$data</span>['prefix4'<span style="color: #000000;">]);

        </span><span style="color: #0000ff;">if</span>(<span style="color: #800080;">$data</span>['prefix'] != self::<span style="color: #000000;">HEADER_MAGIC_PREFIX) {
            </span><span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> CrxParserException("header parse: illegal prefix"<span style="color: #000000;">);
        }
        </span><span style="color: #0000ff;">if</span>( <span style="color: #800080;">$data</span>['version'] != self::<span style="color: #000000;">CURRENT_VERSION ) {
            </span><span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> CrxParserException("header parse: illegal version"<span style="color: #000000;">);
        }
        </span><span style="color: #0000ff;">if</span><span style="color: #000000;">(
                </span><span style="color: #0000ff;">empty</span>(<span style="color: #800080;">$data</span>['key_size']) || <span style="color: #800080;">$data</span>['key_size'] > self::MAX_PUBLIC_KEY_SIZE ||
                <span style="color: #0000ff;">empty</span>(<span style="color: #800080;">$data</span>['sig_size']) || <span style="color: #800080;">$data</span>['sig_size'] > self::<span style="color: #000000;">MAX_SIGNATURE_SIZE
                ){
                    </span><span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> CrxParserException("header parse: illegal public key size or signature size"<span style="color: #000000;">);
        }
        </span><span style="color: #800080;">$this</span>->_header = <span style="color: #800080;">$data</span><span style="color: #000000;">;
    }

    </span><span style="color: #008000;">/*</span><span style="color: #008000;">*
     * 解析key
     * @throws CrxParserException
     </span><span style="color: #008000;">*/</span>
    <span style="color: #0000ff;">private</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> parse_key() {
        </span><span style="color: #800080;">$key</span> = <span style="color: #008080;">fread</span>(<span style="color: #800080;">$this</span>->fp,<span style="color: #800080;">$this</span>->_header['key_size'<span style="color: #000000;">]);
        </span><span style="color: #0000ff;">if</span>(<span style="color: #800080;">$key</span><span style="color: #000000;">) {
            </span><span style="color: #800080;">$this</span>->_key = <span style="color: #800080;">$key</span><span style="color: #000000;">;
        }</span><span style="color: #0000ff;">else</span><span style="color: #000000;">{
            </span><span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> CrxParserException("key parse: error reading key"<span style="color: #000000;">);
        }
    }

    </span><span style="color: #008000;">/*</span><span style="color: #008000;">*
     * 解析sig
     * @throws CrxParserException
     </span><span style="color: #008000;">*/</span>
    <span style="color: #0000ff;">private</span> <span style="color: #0000ff;">function</span><span style="color: #000000;"> parse_sig() {
        </span><span style="color: #800080;">$sig</span> = <span style="color: #008080;">fread</span>(<span style="color: #800080;">$this</span>->fp,<span style="color: #800080;">$this</span>->_header['sig_size'<span style="color: #000000;">]);
        </span><span style="color: #0000ff;">if</span>(<span style="color: #800080;">$sig</span><span style="color: #000000;">) {
            </span><span style="color: #800080;">$this</span>->_sig = <span style="color: #800080;">$sig</span><span style="color: #000000;">;
        }</span><span style="color: #0000ff;">else</span><span style="color: #000000;">{
            </span><span style="color: #0000ff;">throw</span> <span style="color: #0000ff;">new</span> CrxParserException("sig parse: error reading sig"<span style="color: #000000;">);
        }
    }

    </span><span style="color: #008000;">/*</span><span style="color: #008000;">*
     * 从文件中获取指定位置及大小的内容
     * @param unknown $filename
     * @param number $offset
     * @param unknown $length
     * @return string
     </span><span style="color: #008000;">*/</span>
    <span style="color: #0000ff;">private</span> <span style="color: #0000ff;">function</span> getContent(<span style="color: #800080;">$filename</span>,<span style="color: #800080;">$offset</span>=0,<span style="color: #800080;">$length</span>=-1<span style="color: #000000;">){
        </span><span style="color: #800080;">$stream</span> = <span style="color: #008080;">fopen</span>(<span style="color: #800080;">$filename</span>, 'rb'<span style="color: #000000;">);
        </span><span style="color: #800080;">$content</span> = <span style="color: #008080;">stream_get_contents</span>(<span style="color: #800080;">$stream</span>, <span style="color: #800080;">$length</span>, <span style="color: #800080;">$offset</span><span style="color: #000000;">);
        </span><span style="color: #008080;">fclose</span>(<span style="color: #800080;">$stream</span><span style="color: #000000;">);
        </span><span style="color: #0000ff;">return</span> <span style="color: #800080;">$content</span><span style="color: #000000;">;
    }

}</span>

How to use:

<?<span style="color: #000000;">php
</span><span style="color: #800080;">$crxParser</span>=<span style="color: #0000ff;">new</span> CrxParser('abc.crx'<span style="color: #000000;">);
</span><span style="color: #0000ff;">echo</span> <span style="color: #800080;">$crxParser</span>-><span style="color: #000000;">getAppid();
</span><span style="color: #008080;">var_dump</span>(<span style="color: #800080;">$crxParser</span>-><span style="color: #000000;">getConfig());
</span><span style="color: #008000;">//</span><span style="color: #008000;">$crxParser->convertToZip('abc.zip');</span>