1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
|
/*
* $Id: SaslInputStream.java,v 1.3 2004/06/08 19:05:28 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 <a href="mailto:dog@gnu.org">Chris Burdess</a>
* @version $Revision: 1.3 $ $Date: 2004/06/08 19:05:28 $
*/
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 < l; i++)
{
bytes[off + l2] = 0;
}
return l2;
}
}
}
|
