/*
* Copyright (c) 2003 The Visigoth Software Society. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Visigoth Software Society (http://www.visigoths.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. Neither the name "FreeMarker", "Visigoth", nor any of the names of the
* project contributors may be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact visigoths@visigoths.org.
*
* 5. Products derived from this software may not be called "FreeMarker" or "Visigoth"
* nor may "FreeMarker" or "Visigoth" appear in their names
* without prior written permission of the Visigoth Software Society.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE VISIGOTH SOFTWARE SOCIETY OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Visigoth Software Society. For more
* information on the Visigoth Software Society, please see
* http://www.visigoths.org/
*/
package freemarker.cache;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import freemarker.template.utility.SecurityUtilities;
/**
* A {@link TemplateLoader} that uses files in a specified directory as the
* source of templates. If contains security checks that will prevent it
* serving templates outside the template directory (like <code><include /etc/passwd></code>.
* It compares canonical paths for this, so templates that are symbolically
* linked into the template directory from outside of it won't work either.
* @author Attila Szegedi, szegedia at freemail dot hu
* @version $Id: FileTemplateLoader.java,v 1.26 2004/03/29 08:06:22 szegedia Exp $
*/
public class FileTemplateLoader implements TemplateLoader
{
private static final boolean SEP_IS_SLASH = File.separatorChar == '/';
public final File baseDir;
private final String canonicalPath;
/**
* Creates a new file template cache that will use the current directory
* (the value of the system property <code>user.dir</code> as the base
* directory for loading templates. It will not allow access to template
* files that are accessible through symlinks that point outside the
* base directory.
*/
public FileTemplateLoader()
throws
IOException
{
this(new File(SecurityUtilities.getSystemProperty("user.dir")));
}
/**
* Creates a new file template loader that will use the specified directory
* as the base directory for loading templates. It will not allow access to
* template files that are accessible through symlinks that point outside
* the base directory.
* @param baseDir the base directory for loading templates
*/
public FileTemplateLoader(final File baseDir)
throws
IOException
{
this(baseDir, false);
}
/**
* Creates a new file template loader that will use the specified directory
* as the base directory for loading templates.
* @param baseDir the base directory for loading templates
* @param allowLinking if true, it will allow
*/
public FileTemplateLoader(final File baseDir, final boolean allowLinking)
throws
IOException
{
try {
Object[] retval = (Object[]) AccessController.doPrivileged(new PrivilegedExceptionAction() {
public Object run() throws IOException {
if (!baseDir.exists()) {
throw new FileNotFoundException(baseDir + " does not exist.");
}
if (!baseDir.isDirectory()) {
throw new IOException(baseDir + " is not a directory.");
}
Object[] retval = new Object[2];
if(allowLinking) {
retval[0] = baseDir;
retval[1] = null;
}
else {
retval[0] = baseDir.getCanonicalFile();
String basePath = ((File) retval[0]).getPath();
// Most canonical paths don't end with File.separator,
// but some does. Like, "C:\" VS "C:\templates".
if (!basePath.endsWith(File.separator)) {
basePath += File.separatorChar;
}
retval[1] = basePath;
}
return retval;
}
});
this.baseDir = (File) retval[0];
this.canonicalPath = (String) retval[1];
}
catch(PrivilegedActionException e)
{
throw (IOException)e.getException();
}
}
public Object findTemplateSource(final String name)
throws
IOException
{
try {
return AccessController.doPrivileged(new PrivilegedExceptionAction() {
public Object run() throws IOException {
File source = new File(baseDir, SEP_IS_SLASH ? name :
name.replace('/', File.separatorChar));
if(!source.isFile()) {
return null;
}
// Security check for inadvertently returning something
// outside the template directory when linking is not
// allowed.
if(canonicalPath != null) {
String normalized = source.getCanonicalPath();
if (!normalized.startsWith(canonicalPath)) {
throw new SecurityException(source.getAbsolutePath()
+ " resolves to " + normalized + " which " +
" doesn't start with " + canonicalPath);
}
}
return source;
}
});
}
catch(PrivilegedActionException e)
{
throw (IOException)e.getException();
}
}
public long getLastModified(final Object templateSource)
{
return ((Long)(AccessController.doPrivileged(new PrivilegedAction()
{
public Object run()
{
return new Long(((File)templateSource).lastModified());
}
}))).longValue();
}
public Reader getReader(final Object templateSource, final String encoding)
throws
IOException
{
try
{
return (Reader)AccessController.doPrivileged(new PrivilegedExceptionAction()
{
public Object run()
throws
IOException
{
if (!(templateSource instanceof File)) {
throw new IllegalArgumentException(
"templateSource is a: " +
templateSource.getClass().getName());
}
return new InputStreamReader(new FileInputStream(
(File)templateSource), encoding);
}
});
}
catch(PrivilegedActionException e)
{
throw (IOException)e.getException();
}
}
public void closeTemplateSource(Object templateSource)
{
// Do nothing.
}
}