/* * $Id: SaslInputStream.java,v 1.1 2003/10/19 08:51:37 dog Exp $ * Copyright (C) 2002 The Free Software Foundation * * This file is part of GNU inetlib, a library. * * GNU inetlib is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * GNU inetlib is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * As a special exception, if you link this library with other files to * produce an executable, this library does not by itself cause the * resulting executable to be covered by the GNU General Public License. * This exception does not however invalidate any other reasons why the * executable file might be covered by the GNU General Public License. */ package gnu.inet.util; import java.io.FilterInputStream; import java.io.InputStream; import java.io.IOException; import javax.security.sasl.SaslClient; /** * A filter input stream that decodes all its received input using a SASL * client. * * @author Chris Burdess * @version $Revision: 1.1 $ $Date: 2003/10/19 08:51:37 $ */ public class SaslInputStream extends FilterInputStream { /* * The SASL client. */ private final SaslClient sasl; /* * Overflow buffer. */ private byte[] buf; /* * Offset in overflow buffer. */ private int pos; /** * Constructor. * @param sasl the SASL client * @param in the underlying input stream */ public SaslInputStream(SaslClient sasl, InputStream in) { super(in); this.sasl = sasl; } /** * Reads a single character. */ public int read() throws IOException { if (buf!=null) { // Return next characer in buffer int c = (int)buf[pos++]; if (pos==buf.length) buf = null; return c; } int c = super.read(); if (c==-1) return c; byte[] bytes = new byte[1]; byte[] unwrapped = sasl.unwrap(bytes, 0, 1); // FIXME if we get 0 bytes, we have a problem c = (int)unwrapped[0]; if (unwrapped.length>1) { // Store in overflow buffer int l = unwrapped.length-1; buf = new byte[l]; System.arraycopy(unwrapped, 1, buf, 0, l); pos = 0; } return c; } public int read(byte[] bytes) throws IOException { return read(bytes, 0, bytes.length); } /** * Block read. */ public int read(byte[] bytes, int off, int len) throws IOException { if (buf!=null) { // Return bytes from buffer int l = buf.length; if (l-pos<=len) { System.arraycopy(buf, pos, bytes, off, l); buf = null; return l; } else { System.arraycopy(buf, pos, bytes, off, len); pos += len; return len; } } int l = super.read(bytes, off, len); if (l==-1) return l; byte[] unwrapped = sasl.unwrap(bytes, off, l); int l2 = unwrapped.length; if (l2>len) { // Store excess bytes in buffer int d = l2-len; buf = new byte[d]; System.arraycopy(unwrapped, 0, bytes, off, len); System.arraycopy(unwrapped, len, buf, 0, d); pos = 0; return len; } else { System.arraycopy(unwrapped, 0, bytes, off, l2); // Zero bytes from l2..l to ensure none of the original // bytes received can be read by the caller for (int i=l2; i