1 /*
2 * Copyright (c) 2004, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.security.ssl;
27
28 import java.nio.*;
29
30 /*
31 * A multi-purpose class which handles all of the SSLEngine arguments.
32 * It validates arguments, checks for RO conditions, does space
33 * calculations, performs scatter/gather, etc.
34 *
35 * @author Brad R. Wetmore
36 */
37 class EngineArgs {
38
39 /*
40 * Keep track of the input parameters.
41 */
42 ByteBuffer netData;
43 ByteBuffer [] appData;
44
45 private int offset; // offset/len for the appData array.
46 private int len;
47
48 /*
49 * The initial pos/limit conditions. This is useful because we can
50 * quickly calculate the amount consumed/produced in successful
51 * operations, or easily return the buffers to their pre-error
52 * conditions.
53 */
54 private int netPos;
55 private int netLim;
56
57 private int [] appPoss;
58 private int [] appLims;
59
60 /*
61 * Sum total of the space remaining in all of the appData buffers
62 */
63 private int appRemaining = 0;
64
65 private boolean wrapMethod;
66
67 /*
68 * Called by the SSLEngine.wrap() method.
69 */
70 EngineArgs(ByteBuffer [] appData, int offset, int len,
71 ByteBuffer netData) {
72 this.wrapMethod = true;
73 init(netData, appData, offset, len);
74 }
75
76 /*
77 * Called by the SSLEngine.unwrap() method.
78 */
79 EngineArgs(ByteBuffer netData, ByteBuffer [] appData, int offset,
80 int len) {
81 this.wrapMethod = false;
82 init(netData, appData, offset, len);
83 }
84
85 /*
86 * The main initialization method for the arguments. Most
87 * of them are pretty obvious as to what they do.
88 *
89 * Since we're already iterating over appData array for validity
90 * checking, we also keep track of how much remainging space is
91 * available. Info is used in both unwrap (to see if there is
92 * enough space available in the destination), and in wrap (to
93 * determine how much more we can copy into the outgoing data
94 * buffer.
95 */
96 private void init(ByteBuffer netData, ByteBuffer [] appData,
97 int offset, int len) {
98
99 if ((netData == null) || (appData == null)) {
100 throw new IllegalArgumentException("src/dst is null");
101 }
102
103 if ((offset < 0) || (len < 0) || (offset > appData.length - len)) {
104 throw new IndexOutOfBoundsException();
105 }
106
107 if (wrapMethod && netData.isReadOnly()) {
108 throw new ReadOnlyBufferException();
109 }
110
111 netPos = netData.position();
112 netLim = netData.limit();
113
114 appPoss = new int [appData.length];
115 appLims = new int [appData.length];
116
117 for (int i = offset; i < offset + len; i++) {
118 if (appData[i] == null) {
119 throw new IllegalArgumentException(
120 "appData[" + i + "] == null");
121 }
122
123 /*
124 * If we're unwrapping, then check to make sure our
125 * destination bufffers are writable.
126 */
127 if (!wrapMethod && appData[i].isReadOnly()) {
128 throw new ReadOnlyBufferException();
129 }
130
131 appRemaining += appData[i].remaining();
132
133 appPoss[i] = appData[i].position();
134 appLims[i] = appData[i].limit();
135 }
136
137 /*
138 * Ok, looks like we have a good set of args, let's
139 * store the rest of this stuff.
140 */
141 this.netData = netData;
142 this.appData = appData;
143 this.offset = offset;
144 this.len = len;
145 }
146
147 /*
148 * Given spaceLeft bytes to transfer, gather up that much data
149 * from the appData buffers (starting at offset in the array),
150 * and transfer it into the netData buffer.
151 *
152 * The user has already ensured there is enough room.
153 */
154 void gather(int spaceLeft) {
155 for (int i = offset; (i < (offset + len)) && (spaceLeft > 0); i++) {
156 int amount = Math.min(appData[i].remaining(), spaceLeft);
157 appData[i].limit(appData[i].position() + amount);
158 netData.put(appData[i]);
159 appRemaining -= amount;
160 spaceLeft -= amount;
161 }
162 }
163
164 /*
165 * Using the supplied buffer, scatter the data into the appData buffers
166 * (starting at offset in the array).
167 *
168 * The user has already ensured there is enough room.
169 */
170 void scatter(ByteBuffer readyData) {
171 int amountLeft = readyData.remaining();
172
173 for (int i = offset; (i < (offset + len)) && (amountLeft > 0);
174 i++) {
175 int amount = Math.min(appData[i].remaining(), amountLeft);
176 readyData.limit(readyData.position() + amount);
177 appData[i].put(readyData);
178 amountLeft -= amount;
179 }
180 assert(readyData.remaining() == 0);
181 }
182
183 int getAppRemaining() {
184 return appRemaining;
185 }
186
187 /*
188 * Calculate the bytesConsumed/byteProduced. Aren't you glad
189 * we saved this off earlier?
190 */
191 int deltaNet() {
192 return (netData.position() - netPos);
193 }
194
195 /*
196 * Calculate the bytesConsumed/byteProduced. Aren't you glad
197 * we saved this off earlier?
198 */
199 int deltaApp() {
200 int sum = 0; // Only calculating 2^14 here, don't need a long.
201
202 for (int i = offset; i < offset + len; i++) {
203 sum += appData[i].position() - appPoss[i];
204 }
205
206 return sum;
207 }
208
209 /*
210 * In the case of Exception, we want to reset the positions
211 * to appear as though no data has been consumed or produced.
212 *
213 * Currently, this method is only called as we are preparing to
214 * fail out, and thus we don't need to actually recalculate
215 * appRemaining. If that assumption changes, that variable should
216 * be updated here.
217 */
218 void resetPos() {
219 netData.position(netPos);
220 for (int i = offset; i < offset + len; i++) {
221 // See comment above about recalculating appRemaining.
222 appData[i].position(appPoss[i]);
223 }
224 }
225
226 /*
227 * We are doing lots of ByteBuffer manipulations, in which case
228 * we need to make sure that the limits get set back correctly.
229 * This is one of the last things to get done before returning to
230 * the user.
231 */
232 void resetLim() {
233 netData.limit(netLim);
234 for (int i = offset; i < offset + len; i++) {
235 appData[i].limit(appLims[i]);
236 }
237 }
238 }