DiskFileItemFactory.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.tomcat.util.http.fileupload.disk;
import java.io.File;
import org.apache.tomcat.util.http.fileupload.FileItem;
import org.apache.tomcat.util.http.fileupload.FileItemFactory;
/**
* <p>The default {@link org.apache.tomcat.util.http.fileupload.FileItemFactory}
* implementation. This implementation creates
* {@link org.apache.tomcat.util.http.fileupload.FileItem} instances which keep
* their
* content either in memory, for smaller items, or in a temporary file on disk,
* for larger items. The size threshold, above which content will be stored on
* disk, is configurable, as is the directory in which temporary files will be
* created.</p>
*
* <p>If not otherwise configured, the default configuration values are as
* follows:</p>
* <ul>
* <li>Size threshold is 10 KiB.</li>
* <li>Repository is the system default temp directory, as returned by
* {@code System.getProperty("java.io.tmpdir")}.</li>
* </ul>
* <p>
* <b>NOTE</b>: Files are created in the system default temp directory with
* predictable names. This means that a local attacker with write access to that
* directory can perform a TOUTOC attack to replace any uploaded file with a
* file of the attackers choice. The implications of this will depend on how the
* uploaded file is used but could be significant. When using this
* implementation in an environment with local, untrusted users,
* {@link #setRepository(File)} MUST be used to configure a repository location
* that is not publicly writable. In a Servlet container the location identified
* by the ServletContext attribute {@code javax.servlet.context.tempdir}
* may be used.
* </p>
*
* <p>Temporary files, which are created for file items, will be deleted when
* the associated request is recycled.</p>
*
* @since 1.1
*/
public class DiskFileItemFactory implements FileItemFactory {
// ----------------------------------------------------- Manifest constants
/**
* The default threshold above which uploads will be stored on disk.
*/
public static final int DEFAULT_SIZE_THRESHOLD = 10240;
// ----------------------------------------------------- Instance Variables
/**
* The directory in which uploaded files will be stored, if stored on disk.
*/
private File repository;
/**
* The threshold above which uploads will be stored on disk.
*/
private int sizeThreshold = DEFAULT_SIZE_THRESHOLD;
/**
* Default content charset to be used when no explicit charset
* parameter is provided by the sender.
*/
private String defaultCharset = DiskFileItem.DEFAULT_CHARSET;
// ----------------------------------------------------------- Constructors
/**
* Constructs an unconfigured instance of this class. The resulting factory
* may be configured by calling the appropriate setter methods.
*/
public DiskFileItemFactory() {
this(DEFAULT_SIZE_THRESHOLD, null);
}
/**
* Constructs a preconfigured instance of this class.
*
* @param sizeThreshold The threshold, in bytes, below which items will be
* retained in memory and above which they will be
* stored as a file.
* @param repository The data repository, which is the directory in
* which files will be created, should the item size
* exceed the threshold.
*/
public DiskFileItemFactory(final int sizeThreshold, final File repository) {
this.sizeThreshold = sizeThreshold;
this.repository = repository;
}
// ------------------------------------------------------------- Properties
/**
* Returns the directory used to temporarily store files that are larger
* than the configured size threshold.
*
* @return The directory in which temporary files will be located.
*
* @see #setRepository(java.io.File)
*
*/
public File getRepository() {
return repository;
}
/**
* Sets the directory used to temporarily store files that are larger
* than the configured size threshold.
*
* @param repository The directory in which temporary files will be located.
*
* @see #getRepository()
*
*/
public void setRepository(final File repository) {
this.repository = repository;
}
/**
* Returns the size threshold beyond which files are written directly to
* disk. The default value is 10240 bytes.
*
* @return The size threshold, in bytes.
*
* @see #setSizeThreshold(int)
*/
public int getSizeThreshold() {
return sizeThreshold;
}
/**
* Sets the size threshold beyond which files are written directly to disk.
*
* @param sizeThreshold The size threshold, in bytes.
*
* @see #getSizeThreshold()
*
*/
public void setSizeThreshold(final int sizeThreshold) {
this.sizeThreshold = sizeThreshold;
}
// --------------------------------------------------------- Public Methods
/**
* Create a new {@link DiskFileItem}
* instance from the supplied parameters and the local factory
* configuration.
*
* @param fieldName The name of the form field.
* @param contentType The content type of the form field.
* @param isFormField {@code true} if this is a plain form field;
* {@code false} otherwise.
* @param fileName The name of the uploaded file, if any, as supplied
* by the browser or other client.
*
* @return The newly created file item.
*/
@Override
public FileItem createItem(final String fieldName, final String contentType,
final boolean isFormField, final String fileName) {
final DiskFileItem result = new DiskFileItem(fieldName, contentType,
isFormField, fileName, sizeThreshold, repository);
result.setDefaultCharset(defaultCharset);
return result;
}
/**
* Returns the default charset for use when no explicit charset
* parameter is provided by the sender.
* @return the default charset
*/
public String getDefaultCharset() {
return defaultCharset;
}
/**
* Sets the default charset for use when no explicit charset
* parameter is provided by the sender.
* @param pCharset the default charset
*/
public void setDefaultCharset(final String pCharset) {
defaultCharset = pCharset;
}
}