Changeset 51653

Timestamp:

08/24/2021 08:50:21 PM (5 years ago)

Author:

azaozz

Message:

Media: Fix wp_unique_filename() to check for name collisions with all alternate file names when an image may be converted after uploading. This includes possible collinions with pre-existing images whose sub-sizes/thumbnails are regenerated.

Props ianmjones, azaozz.
Fixes #53668.

Location:

trunk

Files:

• src/wp-includes/class-wp-image-editor.php (modified) (1 diff)
• src/wp-includes/functions.php (modified) (7 diffs)
• tests/phpunit/data/images/test-image-1-100x100.jpg (added)
• tests/phpunit/data/images/test-image-2.gif (added)
• tests/phpunit/data/images/test-image-3.jpg (added)
• tests/phpunit/data/images/test-image-4.png (added)
• tests/phpunit/tests/functions.php (modified) (3 diffs)

trunk/src/wp-includes/class-wp-image-editor.php

@@ -592 +592 @@
          */
         protected static function get_extension( $mime_type = null ) {
-                $extensions = explode( '|', array_search( $mime_type, wp_get_mime_types(), true ) );
-
-                if ( empty( $extensions[0] ) ) {
+                if ( empty( $mime_type ) ) {
                         return false;
                 }
 
-                return $extensions[0];
+                return wp_get_default_extension_for_mime_type( $mime_type );
         }
 }

trunk/src/wp-includes/functions.php

@@ -2489 +2489 @@
         $ext2     = null;
 
+        // Initialize vars used in the wp_unique_filename filter.
+        $number        = '';
+        $alt_filenames = array();
+
         // Separate the filename into a name and extension.
         $ext  = pathinfo( $filename, PATHINFO_EXTENSION );
@@ -2509 +2513 @@
                 $filename = call_user_func( $unique_filename_callback, $dir, $name, $ext );
         } else {
-                $number = '';
-                $fname  = pathinfo( $filename, PATHINFO_FILENAME );
+                $fname = pathinfo( $filename, PATHINFO_FILENAME );
 
                 // Always append a number to file names that can potentially match image sub-size file names.
@@ -2520 +2523 @@
                 }
 
-                // Change '.ext' to lower case.
-                if ( $ext && strtolower( $ext ) != $ext ) {
-                        $ext2      = strtolower( $ext );
-                        $filename2 = preg_replace( '|' . preg_quote( $ext ) . '$|', $ext2, $filename );
-
-                        // Check for both lower and upper case extension or image sub-sizes may be overwritten.
-                        while ( file_exists( $dir . "/{$filename}" ) || file_exists( $dir . "/{$filename2}" ) ) {
-                                $new_number = (int) $number + 1;
-                                $filename   = str_replace( array( "-{$number}{$ext}", "{$number}{$ext}" ), "-{$new_number}{$ext}", $filename );
-                                $filename2  = str_replace( array( "-{$number}{$ext2}", "{$number}{$ext2}" ), "-{$new_number}{$ext2}", $filename2 );
-                                $number     = $new_number;
+                // Get the mime type. Uploaded files were already checked with wp_check_filetype_and_ext()
+                // in _wp_handle_upload(). Using wp_check_filetype() would be sufficient here.
+                $file_type = wp_check_filetype( $filename );
+                $mime_type = $file_type['type'];
+
+                $is_image    = ( ! empty( $mime_type ) && 0 === strpos( $mime_type, 'image/' ) );
+                $upload_dir  = wp_get_upload_dir();
+                $lc_filename = null;
+
+                $lc_ext = strtolower( $ext );
+                $_dir   = trailingslashit( $dir );
+
+                // If the extension is uppercase add an alternate file name with lowercase extension. Both need to be tested
+                // for uniqueness as the extension will be changed to lowercase for better compatibility with different filesystems.
+                // Fixes an inconsistency in WP < 2.9 where uppercase extensions were allowed but image sub-sizes were created with
+                // lowercase extensions.
+                if ( $ext && $lc_ext !== $ext ) {
+                        $lc_filename = preg_replace( '|' . preg_quote( $ext ) . '$|', $lc_ext, $filename );
+                }
+
+                // Increment the number added to the file name if there are any files in $dir whose names match one of the
+                // possible name variations.
+                while ( file_exists( $_dir . $filename ) || ( $lc_filename && file_exists( $_dir . $lc_filename ) ) ) {
+                        $new_number = (int) $number + 1;
+
+                        if ( $lc_filename ) {
+                                $lc_filename = str_replace( array( "-{$number}{$lc_ext}", "{$number}{$lc_ext}" ), "-{$new_number}{$lc_ext}", $lc_filename );
                         }
 
-                        $filename = $filename2;
-                } else {
-                        while ( file_exists( $dir . "/{$filename}" ) ) {
-                                $new_number = (int) $number + 1;
-
-                                if ( '' === "{$number}{$ext}" ) {
-                                        $filename = "{$filename}-{$new_number}";
-                                } else {
-                                        $filename = str_replace( array( "-{$number}{$ext}", "{$number}{$ext}" ), "-{$new_number}{$ext}", $filename );
-                                }
-
-                                $number = $new_number;
+                        if ( '' === "{$number}{$ext}" ) {
+                                $filename = "{$filename}-{$new_number}";
+                        } else {
+                                $filename = str_replace( array( "-{$number}{$ext}", "{$number}{$ext}" ), "-{$new_number}{$ext}", $filename );
                         }
+
+                        $number = $new_number;
+                }
+
+                // Change the extension to lowercase if needed.
+                if ( $lc_filename ) {
+                        $filename = $lc_filename;
                 }
 
                 // Prevent collisions with existing file names that contain dimension-like strings
                 // (whether they are subsizes or originals uploaded prior to #42437).
-                $upload_dir = wp_get_upload_dir();
+
+                $files = array();
+                $count = 10000;
 
                 // The (resized) image files would have name and extension, and will be in the uploads dir.
@@ -2580 +2600 @@
 
                         if ( ! empty( $files ) ) {
-                                // The extension case may have changed above.
-                                $new_ext = ! empty( $ext2 ) ? $ext2 : $ext;
+                                $count = count( $files );
 
                                 // Ensure this never goes into infinite loop
                                 // as it uses pathinfo() and regex in the check, but string replacement for the changes.
-                                $count = count( $files );
-                                $i     = 0;
+                                $i = 0;
 
                                 while ( $i <= $count && _wp_check_existing_file_names( $filename, $files ) ) {
                                         $new_number = (int) $number + 1;
-                                        $filename   = str_replace( array( "-{$number}{$new_ext}", "{$number}{$new_ext}" ), "-{$new_number}{$new_ext}", $filename );
-                                        $number     = $new_number;
+
+                                        // If $ext is uppercase it was replaced with the lowercase version after the previous loop.
+                                        $filename = str_replace( array( "-{$number}{$lc_ext}", "{$number}{$lc_ext}" ), "-{$new_number}{$lc_ext}", $filename );
+
+                                        $number = $new_number;
                                         $i++;
                                 }
                         }
                 }
+
+                // Check if an image will be converted after uploading or some existing images sub-sizes file names may conflict
+                // when regenerated. If yes, ensure the new file name will be unique and will produce unique sub-sizes.
+                if ( $is_image ) {
+                        $output_formats = apply_filters( 'image_editor_output_format', array(), $_dir . $filename, $mime_type );
+                        $alt_types      = array();
+
+                        if ( ! empty( $output_formats[ $mime_type ] ) ) {
+                                // The image will be converted to this format/mime type.
+                                $alt_mime_type = $output_formats[ $mime_type ];
+
+                                // Other types of images whose names may conflict if their sub-sizes are regenerated.
+                                $alt_types = array_keys( array_intersect( $output_formats, array( $mime_type, $alt_mime_type ) ) );
+                                $alt_types[] = $alt_mime_type;
+                        } elseif ( ! empty( $output_formats ) ) {
+                                $alt_types = array_keys( array_intersect( $output_formats, array( $mime_type ) ) );
+                        }
+
+                        // Remove duplicates and the original mime type. It will be added later if needed.
+                        $alt_types = array_unique( array_diff( $alt_types, array( $mime_type ) ) );
+
+                        foreach ( $alt_types as $alt_type ) {
+                                $alt_ext = wp_get_default_extension_for_mime_type( $alt_type );
+
+                                if ( ! $alt_ext ) {
+                                        continue;
+                                }
+
+                                $alt_ext      = ".{$alt_ext}";
+                                $alt_filename = preg_replace( '|' . preg_quote( $lc_ext ) . '$|', $alt_ext, $filename );
+
+                                $alt_filenames[ $alt_ext ] = $alt_filename;
+                        }
+
+                        if ( ! empty( $alt_filenames ) ) {
+                                // Add the original filename. It needs to be checked again together with the alternate filenames
+                                // when $number is incremented.
+                                $alt_filenames[ $lc_ext ] = $filename;
+
+                                // Ensure no infinite loop.
+                                $i = 0;
+
+                                while ( $i <= $count && _wp_check_alternate_file_names( $alt_filenames, $_dir, $files ) ) {
+                                        $new_number = (int) $number + 1;
+
+                                        foreach ( $alt_filenames as $alt_ext => $alt_filename ) {
+                                                $alt_filenames[ $alt_ext ] = str_replace( array( "-{$number}{$alt_ext}", "{$number}{$alt_ext}" ), "-{$new_number}{$alt_ext}", $alt_filename );
+                                        }
+
+                                        // Also update the $number in (the output) $filename.
+                                        // If the extension was uppercase it was already replaced with the lowercase version.
+                                        $filename = str_replace( array( "-{$number}{$lc_ext}", "{$number}{$lc_ext}" ), "-{$new_number}{$lc_ext}", $filename );
+
+                                        $number = $new_number;
+                                        $i++;
+                                }
+                        }
+                }
         }
 
@@ -2602 +2681 @@
          *
          * @since 4.5.0
+         * @since 5.8.1 The `$alt_filenames` and `$number` parameters were added.
          *
          * @param string        $filename                 Unique file name.
@@ -2607 +2687 @@
          * @param string        $dir                      Directory path.
          * @param callable|null $unique_filename_callback Callback function that generates the unique file name.
+         * @param string[]      $alt_filenames            Array of alternate file names that were checked for collisions.
+         * @param int|string    $number                   The highest number that was used to make the file name unique
+         *                                                or an empty string if unused.
          */
-        return apply_filters( 'wp_unique_filename', $filename, $ext, $dir, $unique_filename_callback );
+        return apply_filters( 'wp_unique_filename', $filename, $ext, $dir, $unique_filename_callback, $alt_filenames, $number );
+}
+
+/**
+ * Helper function to test if each of an array of file names could conflict with existing files.
+ *
+ * @since 5.8.1
+ * @access private
+ *
+ * @param string[] $filenames Array of file names to check.
+ * @param string   $dir       The directory containing the files.
+ * @param array    $files     An array of existing files in the directory. May be empty.
+ * @return bool True if the tested file name could match an existing file, false otherwise.
+ */
+function _wp_check_alternate_file_names( $filenames, $dir, $files ) {
+        foreach ( $filenames as $filename ) {
+                if ( file_exists( $dir . $filename ) ) {
+                        return true;
+                }
+
+                if ( ! empty( $files ) && _wp_check_existing_file_names( $filename, $files ) ) {
+                        return true;
+                }
+        }
+
+        return false;
 }
 
@@ -2792 +2900 @@
                 }
         }
+}
+
+/**
+ * Returns first matched extension for the mime-type,
+ * as mapped from wp_get_mime_types().
+ *
+ * @since 5.8.1
+ *
+ * @param string $mime_type
+ *
+ * @return string|false
+ */
+function wp_get_default_extension_for_mime_type( $mime_type ) {
+        $extensions = explode( '|', array_search( $mime_type, wp_get_mime_types(), true ) );
+
+        if ( empty( $extensions[0] ) ) {
+                return false;
+        }
+
+        return $extensions[0];
 }
 

trunk/tests/phpunit/tests/functions.php

@@ -169 +169 @@
 
                 // Sanity check.
-                $this->assertSame( 'abcdefg.png', wp_unique_filename( $testdir, 'abcdefg.png' ), 'Sanitiy check failed' );
-
-                // Check number is appended for file already exists.
+                $this->assertSame( 'abcdefg.png', wp_unique_filename( $testdir, 'abcdefg.png' ), 'Test non-existing file, file name should be unchanged.' );
+
+                // Ensure correct images exist.
                 $this->assertFileExists( $testdir . 'test-image.png', 'Test image does not exist' );
-                $this->assertSame( 'test-image-1.png', wp_unique_filename( $testdir, 'test-image.png' ), 'Number not appended correctly' );
                 $this->assertFileDoesNotExist( $testdir . 'test-image-1.png' );
+
+                // Check number is appended if file already exists.
+                $this->assertSame( 'test-image-1.png', wp_unique_filename( $testdir, 'test-image.png' ), 'File name not unique, number not appended.' );
+
+                // Check file with uppercase extension.
+                $this->assertSame( 'test-image-1.png', wp_unique_filename( $testdir, 'test-image.PNG' ), 'File name with uppercase extension not unique, number not appended.' );
+
+                // Check file name with already added number.
+                $this->assertSame( 'test-image-2-1.gif', wp_unique_filename( $testdir, 'test-image-2.gif' ), 'File name not unique, number not appended correctly.' );
 
                 // Check special chars.
@@ -220 +228 @@
                 $upload_dir['basedir'] = DIR_TESTDATA . '/images/';
                 return $upload_dir;
+        }
+
+        /**
+         * @ticket 53668
+         */
+        function test_wp_unique_filename_with_additional_image_extension() {
+                $testdir = DIR_TESTDATA . '/images/';
+
+                add_filter( 'upload_dir', array( $this, 'upload_dir_patch_basedir' ) );
+
+                // Set conversions for uploaded images.
+                add_filter( 'image_editor_output_format', array( $this, 'image_editor_output_format_handler' ) );
+
+                // Ensure the test images exist.
+                $this->assertFileExists( $testdir . 'test-image-1-100x100.jpg', 'test-image-1-100x100.jpg does not exist' );
+                $this->assertFileExists( $testdir . 'test-image-2.gif', 'test-image-2.gif does not exist' );
+                $this->assertFileExists( $testdir . 'test-image-3.jpg', 'test-image-3.jpg does not exist' );
+                $this->assertFileExists( $testdir . 'test-image-4.png', 'test-image-4.png does not exist' );
+
+                // Standard test: file does not exist and there are no possible intersections with other files.
+                $this->assertSame(
+                        'abcdef.png',
+                        wp_unique_filename( $testdir, 'abcdef.png' ),
+                        'The abcdef.png, abcdef.gif, and abcdef.jpg images do not exist. The file name should not be changed.'
+                );
+
+                // Actual clash recognized.
+                $this->assertSame(
+                        'canola-1.jpg',
+                        wp_unique_filename( $testdir, 'canola.jpg' ),
+                        'The canola.jpg image exists. The file name should be unique.'
+                );
+
+                // Same name with different extension and the image will be converted.
+                $this->assertSame(
+                        'canola-1.png',
+                        wp_unique_filename( $testdir, 'canola.png' ),
+                        'The canola.jpg image exists. Uploading canola.png that will be converted to canola.jpg should produce unique file name.'
+                );
+
+                // Same name with different uppercase extension and the image will be converted.
+                $this->assertSame(
+                        'canola-1.png',
+                        wp_unique_filename( $testdir, 'canola.PNG' ),
+                        'The canola.jpg image exists. Uploading canola.PNG that will be converted to canola.jpg should produce unique file name.'
+                );
+
+                // Actual clash with several images with different extensions.
+                $this->assertSame(
+                        'test-image-5.png',
+                        wp_unique_filename( $testdir, 'test-image.png' ),
+                        'The test-image.png, test-image-1-100x100.jpg, test-image-2.gif, test-image-3.jpg, and test-image-4.png images exist.' .
+                        'All of them may clash when creating sub-sizes or regenerating thumbnails in the future. The filename should be unique.'
+                );
+
+                // Possible clash with regenerated thumbnails in the future.
+                $this->assertSame(
+                        'codeispoetry-1.jpg',
+                        wp_unique_filename( $testdir, 'codeispoetry.jpg' ),
+                        'The codeispoetry.png image exists. When regenerating thumbnails for it they will be converted to JPG.' .
+                        'The name of the newly uploaded codeispoetry.jpg should be made unique.'
+                );
+
+                remove_filter( 'image_editor_output_format', array( $this, 'image_editor_output_format_handler' ) );
+                remove_filter( 'upload_dir', array( $this, 'upload_dir_patch_basedir' ) );
+        }
+
+        /**
+         * Changes the output format when editing images. When uploading a PNG file
+         * it will be converted to JPEG, GIF to JPEG, and PICT to BMP
+         * (if the image editor in PHP supports it).
+         *
+         * @param array $formats
+         *
+         * @return array
+         */
+        public function image_editor_output_format_handler( $formats ) {
+                $formats['image/png'] = 'image/jpeg';
+                $formats['image/gif'] = 'image/jpeg';
+                $formats['image/pct'] = 'image/bmp';
+
+                return $formats;
         }
 
@@ -1947 +2037 @@
                 );
         }
+
+        /**
+         * @ticket 53668
+         */
+        public function test_wp_get_default_extension_for_mime_type() {
+                $this->assertEquals( 'jpg', wp_get_default_extension_for_mime_type( 'image/jpeg' ), 'jpg not returned as default extension for "image/jpeg"' );
+                $this->assertNotEquals( 'jpeg', wp_get_default_extension_for_mime_type( 'image/jpeg' ), 'jpeg should not be returned as default extension for "image/jpeg"' );
+                $this->assertEquals( 'png', wp_get_default_extension_for_mime_type( 'image/png' ), 'png not returned as default extension for "image/png"' );
+                $this->assertFalse( wp_get_default_extension_for_mime_type( 'wibble/wobble' ), 'false not returned for unrecognized mime type' );
+                $this->assertFalse( wp_get_default_extension_for_mime_type( '' ), 'false not returned when empty string as mime type supplied' );
+                $this->assertFalse( wp_get_default_extension_for_mime_type( '   ' ), 'false not returned when empty string as mime type supplied' );
+                $this->assertFalse( wp_get_default_extension_for_mime_type( 123 ), 'false not returned when int as mime type supplied' );
+                $this->assertFalse( wp_get_default_extension_for_mime_type( null ), 'false not returned when null as mime type supplied' );
+        }
 }