DVWA File upload 过关秘籍

 1if( isset( $_POST[ 'Upload' ] ) ) {
 2    // Where are we going to be writing to?
 3    $target_path  = DVWA_WEB_PAGE_TO_ROOT . "hackable/uploads/";
 4    $target_path .= basename( $_FILES[ 'uploaded' ][ 'name' ] );
 5
 6    // Can we move the file to the upload folder?
 7    // 完全没做过滤.
 8    // 上传一个PHP文件也是可以的.
 9    if( !move_uploaded_file( $_FILES[ 'uploaded' ][ 'tmp_name' ], $target_path ) ) {
10        // No
11        echo '<pre>Your image was not uploaded.</pre>';
12    }
13    else {
14        // Yes!
15        echo "<pre>{$target_path} succesfully uploaded!</pre>";
16    }
17}

 1if( isset( $_POST[ 'Upload' ] ) ) {
 2    // Where are we going to be writing to?
 3    $target_path  = DVWA_WEB_PAGE_TO_ROOT . "hackable/uploads/";
 4    $target_path .= basename( $_FILES[ 'uploaded' ][ 'name' ] );
 5
 6    // File information
 7    $uploaded_name = $_FILES[ 'uploaded' ][ 'name' ];
 8    $uploaded_type = $_FILES[ 'uploaded' ][ 'type' ];
 9    $uploaded_size = $_FILES[ 'uploaded' ][ 'size' ];
10
11    // Is it an image?
12    // // 开始做了一些过滤
13
14    // 下面是官方对$_FILES 函数的描述
15    //  [name] => MyFile.txt (comes from the browser, so treat as tainted)
16    //         [type] => text/plain  (not sure where it gets this from - assume the browser, so treat as tainted)
17    //         [tmp_name] => /tmp/php/php1h4j1o (could be anywhere on your system, depending on your config        settings, but the user has no control, so this isn't tainted)
18    //         [error] => UPLOAD_ERR_OK  (= 0)
19    //         [size] => 123   (the size in bytes)
20
21    // 其中对name和type的description的描述都是 `treat as tainted`(被污染的)
22    // 这意味着它有可能会被修改 unsafe
23
24    // 我们可以尝试上传一个PHP文件，使用一些拦截请求工具，修改即将发出的请求.
25    // 来达到修改`name`中的后缀名和`type`中的媒体类型.
26    if( ( $uploaded_type == "image/jpeg" || $uploaded_type == "image/png" ) &&
27        ( $uploaded_size < 100000 ) ) {
28
29        // Can we move the file to the upload folder?
30        if( !move_uploaded_file( $_FILES[ 'uploaded' ][ 'tmp_name' ], $target_path ) ) {
31            // No
32            echo '<pre>Your image was not uploaded.</pre>';
33        }
34        else {
35            // Yes!
36            echo "<pre>{$target_path} succesfully uploaded!</pre>";
37        }
38    }
39    else {
40        // Invalid file
41        echo '<pre>Your image was not uploaded. We can only accept JPEG or PNG images.</pre>';
42    }
43}

 1if( isset( $_POST[ 'Upload' ] ) ) {
 2    // Where are we going to be writing to?
 3    $target_path  = DVWA_WEB_PAGE_TO_ROOT . "hackable/uploads/";
 4    $target_path .= basename( $_FILES[ 'uploaded' ][ 'name' ] );
 5
 6    // File information
 7    $uploaded_name = $_FILES[ 'uploaded' ][ 'name' ];
 8        // jpg
 9    $uploaded_ext  = substr( $uploaded_name, strrpos( $uploaded_name, '.' ) + 1);
10
11    // file size
12    $uploaded_size = $_FILES[ 'uploaded' ][ 'size' ];
13
14    // tmp_name 是临时副本的名字
15    $uploaded_tmp  = $_FILES[ 'uploaded' ][ 'tmp_name' ];
16
17    // Is it an image?
18    // 和上面的比起来多个一个文件后缀名的判断.
19    // strtolower 转小写
20    // 扩展名只要满足jpeg,png或者jpg就行
21    if( ( strtolower( $uploaded_ext ) == "jpg" || strtolower( $uploaded_ext ) == "jpeg" || strtolower( $uploaded_ext ) == "png" ) &&
22        ( $uploaded_size < 100000 ) &&
23        // getimagesize 获取图像信息
24        // 这个函数保证你穿的一定得是个图像
25        // 可以用图片木马绕过
26        getimagesize( $uploaded_tmp ) ) {
27
28        // Can we move the file to the upload folder?
29        if( !move_uploaded_file( $uploaded_tmp, $target_path ) ) {
30            // No
31            echo '<pre>Your image was not uploaded.</pre>';
32        }
33        else {
34            // Yes!
35            echo "<pre>{$target_path} succesfully uploaded!</pre>";
36        }
37    }
38    else {
39        // Invalid file
40        echo '<pre>Your image was not uploaded. We can only accept JPEG or PNG images.</pre>';
41    }
42}

 1if( isset( $_POST[ 'Upload' ] ) ) {
 2    // Where are we going to be writing to?
 3    $target_path  = DVWA_WEB_PAGE_TO_ROOT . "hackable/uploads/";
 4    $target_path .= basename( $_FILES[ 'uploaded' ][ 'name' ] );
 5
 6    // File information
 7    $uploaded_name = $_FILES[ 'uploaded' ][ 'name' ];
 8    $uploaded_ext  = substr( $uploaded_name, strrpos( $uploaded_name, '.' ) + 1);
 9    $uploaded_size = $_FILES[ 'uploaded' ][ 'size' ];
10    $uploaded_tmp  = $_FILES[ 'uploaded' ][ 'tmp_name' ];
11
12    // Is it an image?
13    // 对比上面多验证了文件的后缀名
14    if( ( strtolower( $uploaded_ext ) == "jpg" || strtolower( $uploaded_ext ) == "jpeg" || strtolower( $uploaded_ext ) == "png" ) &&
15        ( $uploaded_size < 100000 ) &&
16
17        // 函数会通过读取文件头，返回图片的长、宽等信息，如果没有相关的图片文件头，函数会报错
18        getimagesize( $uploaded_tmp ) ) {
19
20        // 可以看到，High级别的代码读取文件名中最后一个”.”后的字符串，期望通过文件名来限制文件类型
21        // 因此要求上传文件名形式必须是”*.jpg”、”*.jpeg” 、”*.png”之一
22        // 同时，getimagesize函数更是限制了上传文件的文件头必须为图像类型
23
24        // Can we move the file to the upload folder?
25        if( !move_uploaded_file( $uploaded_tmp, $target_path ) ) {
26            // No
27            echo '<pre>Your image was not uploaded.</pre>';
28        }
29        else {
30            // Yes!
31            echo "<pre>{$target_path} succesfully uploaded!</pre>";
32        }
33    }
34    else {
35        // Invalid file
36        echo '<pre>Your image was not uploaded. We can only accept JPEG or PNG images.</pre>';
37    }
38}

 1if( isset( $_POST[ 'Upload' ] ) ) {
 2    // Check Anti-CSRF token
 3    checkToken( $_REQUEST[ 'user_token' ], $_SESSION[ 'session_token' ], 'index.php' );
 4
 5    // File information
 6    $uploaded_name = $_FILES[ 'uploaded' ][ 'name' ];
 7    $uploaded_ext  = substr( $uploaded_name, strrpos( $uploaded_name, '.' ) + 1);
 8    $uploaded_size = $_FILES[ 'uploaded' ][ 'size' ];
 9    $uploaded_type = $_FILES[ 'uploaded' ][ 'type' ];
10    $uploaded_tmp  = $_FILES[ 'uploaded' ][ 'tmp_name' ];
11
12    // Where are we going to be writing to?
13    $target_path   = DVWA_WEB_PAGE_TO_ROOT . 'hackable/uploads/';
14    //$target_file   = basename( $uploaded_name, '.' . $uploaded_ext ) . '-';
15
16    // MD5 加密
17    $target_file   =  md5( uniqid() . $uploaded_name ) . '.' . $uploaded_ext;
18    $temp_file     = ( ( ini_get( 'upload_tmp_dir' ) == '' ) ? ( sys_get_temp_dir() ) : ( ini_get( 'upload_tmp_dir' ) ) );
19    $temp_file    .= DIRECTORY_SEPARATOR . md5( uniqid() . $uploaded_name ) . '.' . $uploaded_ext;
20
21    // Is it an image?
22    if( ( strtolower( $uploaded_ext ) == 'jpg' || strtolower( $uploaded_ext ) == 'jpeg' || strtolower( $uploaded_ext ) == 'png' ) &&
23        ( $uploaded_size < 100000 ) &&
24        ( $uploaded_type == 'image/jpeg' || $uploaded_type == 'image/png' ) &&
25        getimagesize( $uploaded_tmp ) ) {
26
27        // Strip any metadata, by re-encoding image (Note, using php-Imagick is recommended over php-GD)
28        if( $uploaded_type == 'image/jpeg' ) {
29            $img = imagecreatefromjpeg( $uploaded_tmp );
30            imagejpeg( $img, $temp_file, 100);
31        }
32        else {
33            $img = imagecreatefrompng( $uploaded_tmp );
34            imagepng( $img, $temp_file, 9);
35        }
36        imagedestroy( $img );
37
38        // Can we move the file to the web root from the temp folder?
39        if( rename( $temp_file, ( getcwd() . DIRECTORY_SEPARATOR . $target_path . $target_file ) ) ) {
40            // Yes!
41            echo "<pre><a href='${target_path}${target_file}'>${target_file}</a> succesfully uploaded!</pre>";
42        }
43        else {
44            // No
45            echo '<pre>Your image was not uploaded.</pre>';
46        }
47
48        // Delete any temp files
49        if( file_exists( $temp_file ) )
50            unlink( $temp_file );
51    }
52    else {
53        // Invalid file
54        echo '<pre>Your image was not uploaded. We can only accept JPEG or PNG images.</pre>';
55    }
56}
57
58// Generate Anti-CSRF token
59generateSessionToken();

 1$is_upload = false;
 2$msg = null;
 3if(isset($_POST['submit'])){
 4    // 白名单
 5    $ext_arr = array('jpg','png','gif');
 6    $file_ext = substr($_FILES['upload_file']['name'],strrpos($_FILES['upload_file']['name'],".")+1);
 7    if(in_array($file_ext,$ext_arr)){
 8        $temp_file = $_FILES['upload_file']['tmp_name'];
 9        // 注意这个位置
10        // 最后拼接的储存路径，是由用户提交上的数据来做为路径
11        $img_path = $_POST['save_path']."/".rand(10, 99).date("YmdHis").".".$file_ext;
12
13        if(move_uploaded_file($temp_file,$img_path)){
14            $is_upload = true;
15        } else {
16            $msg = "上传失败";
17        }
18    } else {
19        $msg = "只允许上传.jpg|.png|.gif类型文件！";
20    }
21}