1 /*
2 * Copyright (c) 2000, 2017, 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 /*
27 * (C) Copyright IBM Corp. 1999 All Rights Reserved.
28 * Copyright 1997 The Open Group Research Institute. All rights reserved.
29 */
30
31 package sun.security.krb5;
32
33 import java.util.Arrays;
34 import sun.security.util.*;
35 import sun.security.krb5.internal.*;
36 import sun.security.krb5.internal.crypto.*;
37 import java.io.IOException;
38 import java.math.BigInteger;
39
40 /**
41 * This class encapsulates the concept of a Kerberos checksum.
42 */
43 public class Checksum {
44
45 private int cksumType;
46 private byte[] checksum;
47
48 // ----------------------------------------------+-------------+-----------
49 // Checksum type |sumtype |checksum
50 // |value | size
51 // ----------------------------------------------+-------------+-----------
52 public static final int CKSUMTYPE_NULL = 0; // 0
53 public static final int CKSUMTYPE_CRC32 = 1; // 4
54 public static final int CKSUMTYPE_RSA_MD4 = 2; // 16
55 public static final int CKSUMTYPE_RSA_MD4_DES = 3; // 24
56 public static final int CKSUMTYPE_DES_MAC = 4; // 16
57 public static final int CKSUMTYPE_DES_MAC_K = 5; // 8
58 public static final int CKSUMTYPE_RSA_MD4_DES_K = 6; // 16
59 public static final int CKSUMTYPE_RSA_MD5 = 7; // 16
60 public static final int CKSUMTYPE_RSA_MD5_DES = 8; // 24
61
62 // draft-ietf-krb-wg-crypto-07.txt
63 public static final int CKSUMTYPE_HMAC_SHA1_DES3_KD = 12; // 20
64
65 // draft-raeburn-krb-rijndael-krb-07.txt
66 public static final int CKSUMTYPE_HMAC_SHA1_96_AES128 = 15; // 96
67 public static final int CKSUMTYPE_HMAC_SHA1_96_AES256 = 16; // 96
68
69 // rfc8009
70 public static final int CKSUMTYPE_HMAC_SHA256_128_AES128 = 19; // 96
71 public static final int CKSUMTYPE_HMAC_SHA384_192_AES256 = 20; // 96
72
73 // draft-brezak-win2k-krb-rc4-hmac-04.txt
74 public static final int CKSUMTYPE_HMAC_MD5_ARCFOUR = -138;
75
76 static int CKSUMTYPE_DEFAULT;
77 static int SAFECKSUMTYPE_DEFAULT;
78
79 private static boolean DEBUG = Krb5.DEBUG;
80 static {
81 initStatic();
82 }
83
84 public static void initStatic() {
85 String temp = null;
86 Config cfg = null;
87 try {
88 cfg = Config.getInstance();
89 temp = cfg.get("libdefaults", "default_checksum");
90 if (temp != null)
91 {
92 CKSUMTYPE_DEFAULT = Config.getType(temp);
93 } else {
94 /*
95 * If the default checksum is not
96 * specified in the configuration we
97 * set it to RSA_MD5. We follow the MIT and
98 * SEAM implementation.
99 */
100 CKSUMTYPE_DEFAULT = CKSUMTYPE_RSA_MD5;
101 }
102 } catch (Exception exc) {
103 if (DEBUG) {
104 System.out.println("Exception in getting default checksum "+
105 "value from the configuration " +
106 "Setting default checksum to be RSA-MD5");
107 exc.printStackTrace();
108 }
109 CKSUMTYPE_DEFAULT = CKSUMTYPE_RSA_MD5;
110 }
111
112
113 try {
114 temp = cfg.get("libdefaults", "safe_checksum_type");
115 if (temp != null)
116 {
117 SAFECKSUMTYPE_DEFAULT = Config.getType(temp);
118 } else {
119 SAFECKSUMTYPE_DEFAULT = CKSUMTYPE_RSA_MD5_DES;
120 }
121 } catch (Exception exc) {
122 if (DEBUG) {
123 System.out.println("Exception in getting safe default " +
124 "checksum value " +
125 "from the configuration Setting " +
126 "safe default checksum to be RSA-MD5");
127 exc.printStackTrace();
128 }
129 SAFECKSUMTYPE_DEFAULT = CKSUMTYPE_RSA_MD5_DES;
130 }
131 }
132
133 /**
134 * Constructs a new Checksum using the raw data and type.
135 * @param data the byte array of checksum.
136 * @param new_cksumType the type of checksum.
137 *
138 */
139 // used in InitialToken
140 public Checksum(byte[] data, int new_cksumType) {
141 cksumType = new_cksumType;
142 checksum = data;
143 }
144
145 /**
146 * Constructs a new Checksum by calculating the checksum over the data
147 * using specified checksum type.
148 * @param new_cksumType the type of checksum.
149 * @param data the data that needs to be performed a checksum calculation on.
150 */
151 public Checksum(int new_cksumType, byte[] data)
152 throws KdcErrException, KrbCryptoException {
153
154 cksumType = new_cksumType;
155 CksumType cksumEngine = CksumType.getInstance(cksumType);
156 if (!cksumEngine.isSafe()) {
157 checksum = cksumEngine.calculateChecksum(data, data.length);
158 } else {
159 throw new KdcErrException(Krb5.KRB_AP_ERR_INAPP_CKSUM);
160 }
161 }
162
163 /**
164 * Constructs a new Checksum by calculating the keyed checksum
165 * over the data using specified checksum type.
166 * @param new_cksumType the type of checksum.
167 * @param data the data that needs to be performed a checksum calculation on.
168 */
169 // KrbSafe, KrbTgsReq
170 public Checksum(int new_cksumType, byte[] data,
171 EncryptionKey key, int usage)
172 throws KdcErrException, KrbApErrException, KrbCryptoException {
173 cksumType = new_cksumType;
174 CksumType cksumEngine = CksumType.getInstance(cksumType);
175 if (!cksumEngine.isSafe())
176 throw new KrbApErrException(Krb5.KRB_AP_ERR_INAPP_CKSUM);
177 checksum =
178 cksumEngine.calculateKeyedChecksum(data,
179 data.length,
180 key.getBytes(),
181 usage);
182 }
183
184 /**
185 * Verifies the keyed checksum over the data passed in.
186 */
187 public boolean verifyKeyedChecksum(byte[] data, EncryptionKey key,
188 int usage)
189 throws KdcErrException, KrbApErrException, KrbCryptoException {
190 CksumType cksumEngine = CksumType.getInstance(cksumType);
191 if (!cksumEngine.isSafe())
192 throw new KrbApErrException(Krb5.KRB_AP_ERR_INAPP_CKSUM);
193 return cksumEngine.verifyKeyedChecksum(data,
194 data.length,
195 key.getBytes(),
196 checksum,
197 usage);
198 }
199
200 /*
201 public Checksum(byte[] data) throws KdcErrException, KrbCryptoException {
202 this(Checksum.CKSUMTYPE_DEFAULT, data);
203 }
204 */
205
206 boolean isEqual(Checksum cksum) throws KdcErrException {
207 if (cksumType != cksum.cksumType)
208 return false;
209 CksumType cksumEngine = CksumType.getInstance(cksumType);
210 return CksumType.isChecksumEqual(checksum, cksum.checksum);
211 }
212
213 /**
214 * Constructs an instance of Checksum from an ASN.1 encoded representation.
215 * @param encoding a single DER-encoded value.
216 * @exception Asn1Exception if an error occurs while decoding an ASN1
217 * encoded data.
218 * @exception IOException if an I/O error occurs while reading encoded data.
219 *
220 */
221 private Checksum(DerValue encoding) throws Asn1Exception, IOException {
222 DerValue der;
223 if (encoding.getTag() != DerValue.tag_Sequence) {
224 throw new Asn1Exception(Krb5.ASN1_BAD_ID);
225 }
226 der = encoding.getData().getDerValue();
227 if ((der.getTag() & (byte)0x1F) == (byte)0x00) {
228 cksumType = der.getData().getBigInteger().intValue();
229 }
230 else
231 throw new Asn1Exception(Krb5.ASN1_BAD_ID);
232 der = encoding.getData().getDerValue();
233 if ((der.getTag() & (byte)0x1F) == (byte)0x01) {
234 checksum = der.getData().getOctetString();
235 }
236 else
237 throw new Asn1Exception(Krb5.ASN1_BAD_ID);
238 if (encoding.getData().available() > 0) {
239 throw new Asn1Exception(Krb5.ASN1_BAD_ID);
240 }
241 }
242
243 /**
244 * Encodes a Checksum object.
245 * <pre>{@code
246 * Checksum ::= SEQUENCE {
247 * cksumtype [0] Int32,
248 * checksum [1] OCTET STRING
249 * }
250 * }</pre>
251 *
252 * <p>
253 * This definition reflects the Network Working Group RFC 4120
254 * specification available at
255 * <a href="http://www.ietf.org/rfc/rfc4120.txt">
256 * http://www.ietf.org/rfc/rfc4120.txt</a>.
257 * @return byte array of enocded Checksum.
258 * @exception Asn1Exception if an error occurs while decoding an
259 * ASN1 encoded data.
260 * @exception IOException if an I/O error occurs while reading
261 * encoded data.
262 *
263 */
264 public byte[] asn1Encode() throws Asn1Exception, IOException {
265 DerOutputStream bytes = new DerOutputStream();
266 DerOutputStream temp = new DerOutputStream();
267 temp.putInteger(BigInteger.valueOf(cksumType));
268 bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT,
269 true, (byte)0x00), temp);
270 temp = new DerOutputStream();
271 temp.putOctetString(checksum);
272 bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT,
273 true, (byte)0x01), temp);
274 temp = new DerOutputStream();
275 temp.write(DerValue.tag_Sequence, bytes);
276 return temp.toByteArray();
277 }
278
279
280 /**
281 * Parse (unmarshal) a checksum object from a DER input stream. This form
282 * parsing might be used when expanding a value which is part of
283 * a constructed sequence and uses explicitly tagged type.
284 *
285 * @exception Asn1Exception if an error occurs while decoding an
286 * ASN1 encoded data.
287 * @exception IOException if an I/O error occurs while reading
288 * encoded data.
289 * @param data the Der input stream value, which contains one or more
290 * marshaled value.
291 * @param explicitTag tag number.
292 * @param optional indicates if this data field is optional
293 * @return an instance of Checksum.
294 *
295 */
296 public static Checksum parse(DerInputStream data,
297 byte explicitTag, boolean optional)
298 throws Asn1Exception, IOException {
299
300 if ((optional) &&
301 (((byte)data.peekByte() & (byte)0x1F) != explicitTag)) {
302 return null;
303 }
304 DerValue der = data.getDerValue();
305 if (explicitTag != (der.getTag() & (byte)0x1F)) {
306 throw new Asn1Exception(Krb5.ASN1_BAD_ID);
307 } else {
308 DerValue subDer = der.getData().getDerValue();
309 return new Checksum(subDer);
310 }
311 }
312
313 /**
314 * Returns the raw bytes of the checksum, not in ASN.1 encoded form.
315 */
316 public final byte[] getBytes() {
317 return checksum;
318 }
319
320 public final int getType() {
321 return cksumType;
322 }
323
324 @Override public boolean equals(Object obj) {
325 if (this == obj) {
326 return true;
327 }
328 if (!(obj instanceof Checksum)) {
329 return false;
330 }
331
332 try {
333 return isEqual((Checksum)obj);
334 } catch (KdcErrException kee) {
335 return false;
336 }
337 }
338
339 @Override public int hashCode() {
340 int result = 17;
341 result = 37 * result + cksumType;
342 if (checksum != null) {
343 result = 37 * result + Arrays.hashCode(checksum);
344 }
345 return result;
346 }
347 }