// SimpleGrepFIlter.java
// $Id: SimpleGrepFilter.java,v 1.7 2003/01/27 16:14:54 ylafon Exp $
// (c) COPYRIGHT MIT, INRIA and Keio, 1999.
// Please first read the full copyright statement in file COPYRIGHT.html
package org.w3c.jigedit.filters;
import java.io.IOException;
import java.io.InputStream;
import org.w3c.tools.resources.Attribute;
import org.w3c.tools.resources.AttributeRegistry;
import org.w3c.tools.resources.FramedResource;
import org.w3c.tools.resources.InvalidResourceException;
import org.w3c.tools.resources.ReplyInterface;
import org.w3c.tools.resources.RequestInterface;
import org.w3c.tools.resources.Resource;
import org.w3c.tools.resources.ResourceFilter;
import org.w3c.tools.resources.ResourceFrame;
import org.w3c.tools.resources.ResourceReference;
import org.w3c.tools.resources.StringArrayAttribute;
import org.w3c.tools.resources.StringAttribute;
import org.w3c.www.http.HTTP;
import org.w3c.www.http.HttpEntityMessage;
import org.w3c.www.http.HttpReplyMessage;
import org.w3c.www.http.HttpRequestMessage;
import org.w3c.www.mime.MimeType;
import org.w3c.jigsaw.http.Client;
import org.w3c.jigsaw.http.Reply;
import org.w3c.jigsaw.http.Request;
import org.w3c.jigsaw.frames.HTTPFrame;
public class SimpleGrepFilter extends ResourceFilter {
class ByteArrayComp {
byte[] tab = null;
String string = null;
int idx = -1;
int length = -1;
boolean matchNow(byte c) {
if (tab[idx++] == c) {
return (idx == length);
} else {
idx = 0;
return false;
}
}
void reset() {
idx = 0;
}
String getString() {
return string;
}
ByteArrayComp(String string) {
tab = string.getBytes();
idx = 0;
length = tab.length;
this.string = string;
}
}
protected ByteArrayComp[] forbiddenBytes = null;
/**
* Attribute index - The strings to grep.
*/
protected static int ATTR_FORBIDSTRING_ARRAY = -1;
/**
* Attribute index - The url to redirect.
*/
protected static int ATTR_REDIRECT = -1;
static {
Class c = null;
Attribute a = null;
try {
c = Class.forName("org.w3c.jigedit.filters.SimpleGrepFilter");
} catch (Exception ex) {
ex.printStackTrace();
System.exit(1);
}
a = new StringArrayAttribute("forbidden-strings"
, null
, Attribute.EDITABLE|Attribute.MANDATORY);
ATTR_FORBIDSTRING_ARRAY = AttributeRegistry.registerAttribute(c, a);
a = new StringAttribute("redirect-url"
, null
, Attribute.EDITABLE|Attribute.MANDATORY);
ATTR_REDIRECT = AttributeRegistry.registerAttribute(c, a);
}
protected String[] getForbiddenStrings() {
return (String[]) getValue(ATTR_FORBIDSTRING_ARRAY, null);
}
protected String getRedirectURL() {
return (String) getValue(ATTR_REDIRECT, null);
}
protected ByteArrayComp[] getForbiddenBytes() {
if (forbiddenBytes == null ) {
String[] fstrings = getForbiddenStrings();
forbiddenBytes = new ByteArrayComp[fstrings.length];
for (int i = 0 ; i < fstrings.length; i++)
forbiddenBytes[i] = new ByteArrayComp(fstrings[i]);
}
return forbiddenBytes;
}
/**
* Catch assignements to the forbidden strings attribute.
* <p>When a change to that attribute is detected, the cached value
* are updated.
*/
public void setValue(int idx, Object value) {
super.setValue(idx, value);
if (idx == ATTR_FORBIDSTRING_ARRAY) {
forbiddenBytes = null;
}
}
/**
* Searh for a forbidden string in given stream.
* @param in the InputStream
* @return The String found or <strong>null</strong> if none
* was found.
*/
protected String searchForbiddenStrings(InputStream in) {
if (getForbiddenStrings() == null)
return null;
try {
ByteArrayComp comp[] = getForbiddenBytes();
int len = in.available();
int c;
in.mark(len);
int baclen = comp.length;
for (int j = 0; j < baclen; j++)
comp[j].reset();
while ((c = in.read()) != -1) {
for (int i = 0; i < baclen; i++) {
if (comp[i].matchNow((byte)c)) {
in.reset();
return comp[i].getString();
}
}
}
in.reset();
return null;
} catch (IOException ex) {
return null;
}
}
/**
* Search the forbidden string in the body, if found return
* an ACCES FORBIDDEN Reply.
* @param request The request that is about to be processsed.
*/
public ReplyInterface ingoingFilter(RequestInterface req) {
Request request = (Request) req;
if(request.getMethod().equals("PUT")) {
try {
MimeType req_mt = request.getContentType();
if (req_mt.match(MimeType.TEXT) == MimeType.NO_MATCH)
return null;
} catch (NullPointerException ex) {
// no Content-Type sent! check anyway
}
InputStream in = null;
try {
in = request.getInputStream();
if ( in == null ) {
return null;
}
} catch (IOException ex) {
return null;
}
// verify that the target resource is putable
ResourceReference rr = request.getTargetResource();
if (rr != null) {
try {
FramedResource target = (FramedResource) rr.lock();
HTTPFrame frame = null;
try {
frame = (HTTPFrame) target.getFrame(
Class.forName("org.w3c.jigsaw.frames.HTTPFrame"));
} catch (ClassNotFoundException cex) {
cex.printStackTrace();
//big big problem ...
}
if (frame == null) // can't be putable
return null;
// now we can verify if the target resource is putable
if (! frame.getPutableFlag()) {
return null;
}
// and that the PUT can happen (taken from putFileResource
int cim = frame.checkIfMatch(request);
if ((cim == HTTPFrame.COND_FAILED)
|| (cim == HTTPFrame.COND_WEAK)
|| (frame.checkIfNoneMatch(request) ==
HTTPFrame.COND_FAILED)
|| (frame.checkIfModifiedSince(request) ==
HTTPFrame.COND_FAILED)
|| (frame.checkIfUnmodifiedSince(request) ==
HTTPFrame.COND_FAILED)) {
Reply r = request.makeReply(HTTP.PRECONDITION_FAILED);
r.setContent("Pre-condition failed.");
return r;
}
} catch (InvalidResourceException ex) {
ex.printStackTrace();
// problem ...
} finally {
rr.unlock();
}
}
String expect = request.getExpect();
if (expect != null) {
if (expect.startsWith("100")) { // expect 100?
Client client = request.getClient();
if (client != null) {
try {
client.sendContinue();
} catch (java.io.IOException ex) {
return null;
}
}
}
}
String found = searchForbiddenStrings(in);
if (found != null) {
Reply error = request.makeReply(HTTP.FORBIDDEN);
error.setReason("the string \""+found+"\" is forbidden.");
error.setContent ("<p>the string \""+found+
"\" is forbidden.</p><br> click "+
"<A HREF=\""+getRedirectURL()+"\">here</A>"+
" for explaination.");
return error;
}
return null;
} else
return null;
}
}