001 /*
002 * Copyright 2012-2015 UnboundID Corp.
003 * All Rights Reserved.
004 */
005 /*
006 * Copyright (C) 2015 UnboundID Corp.
007 *
008 * This program is free software; you can redistribute it and/or modify
009 * it under the terms of the GNU General Public License (GPLv2 only)
010 * or the terms of the GNU Lesser General Public License (LGPLv2.1 only)
011 * as published by the Free Software Foundation.
012 *
013 * This program is distributed in the hope that it will be useful,
014 * but WITHOUT ANY WARRANTY; without even the implied warranty of
015 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
016 * GNU General Public License for more details.
017 *
018 * You should have received a copy of the GNU General Public License
019 * along with this program; if not, see <http://www.gnu.org/licenses>.
020 */
021 package com.unboundid.ldap.sdk.unboundidds;
022
023
024
025 import java.text.DecimalFormat;
026 import javax.crypto.Mac;
027 import javax.crypto.SecretKey;
028 import javax.crypto.spec.SecretKeySpec;
029
030 import com.unboundid.ldap.sdk.LDAPException;
031 import com.unboundid.ldap.sdk.ResultCode;
032 import com.unboundid.util.Debug;
033 import com.unboundid.util.StaticUtils;
034 import com.unboundid.util.ThreadSafety;
035 import com.unboundid.util.ThreadSafetyLevel;
036
037 import static com.unboundid.ldap.sdk.unboundidds.UnboundIDDSMessages.*;
038
039
040
041 /**
042 * <BLOCKQUOTE>
043 * <B>NOTE:</B> This class is part of the Commercial Edition of the UnboundID
044 * LDAP SDK for Java. It is not available for use in applications that
045 * include only the Standard Edition of the LDAP SDK, and is not supported for
046 * use in conjunction with non-UnboundID products.
047 * </BLOCKQUOTE>
048 * This class provides support for a number of one-time password algorithms.
049 * Supported algorithms include:
050 * <UL>
051 * <LI>HOTP -- The HMAC-based one-time password algorithm described in
052 * <A HREF="http://www.ietf.org/rfc/rfc4226.txt">RFC 4226</A>.</LI>
053 * <LI>TOTP -- The time-based one-time password algorithm described in
054 * <A HREF="http://www.ietf.org/rfc/rfc6238.txt">RFC 6238</A>.</LI>
055 * </UL>
056 */
057 @ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE)
058 public final class OneTimePassword
059 {
060 /**
061 * The default number of digits to include in generated HOTP passwords.
062 */
063 public static final int DEFAULT_HOTP_NUM_DIGITS = 6;
064
065
066
067 /**
068 * The default time interval (in seconds) to use when generating TOTP
069 * passwords.
070 */
071 public static final int DEFAULT_TOTP_INTERVAL_DURATION_SECONDS = 30;
072
073
074
075 /**
076 * The default number of digits to include in generated TOTP passwords.
077 */
078 public static final int DEFAULT_TOTP_NUM_DIGITS = 6;
079
080
081
082 /**
083 * The name of the MAC algorithm that will be used to perform HMAC-SHA-1
084 * processing.
085 */
086 private static final String HMAC_ALGORITHM_SHA_1 = "HmacSHA1";
087
088
089
090 /**
091 * The name of the secret key spec algorithm that will be used to construct a
092 * secret key from the raw bytes that comprise it.
093 */
094 private static final String KEY_ALGORITHM_RAW = "RAW";
095
096
097
098 /**
099 * Prevent this utility class from being instantiated.
100 */
101 private OneTimePassword()
102 {
103 // No implementation required.
104 }
105
106
107
108 /**
109 * Generates a six-digit HMAC-based one-time-password using the provided
110 * information.
111 *
112 * @param sharedSecret The secret key shared by both parties that will be
113 * using the generated one-time password.
114 * @param counter The counter value that will be used in the course of
115 * generating the one-time password.
116 *
117 * @return The zero-padded string representation of the resulting HMAC-based
118 * one-time password.
119 *
120 * @throws LDAPException If an unexpected problem is encountered while
121 * attempting to generate the one-time password.
122 */
123 public static String hotp(final byte[] sharedSecret, final long counter)
124 throws LDAPException
125 {
126 return hotp(sharedSecret, counter, DEFAULT_HOTP_NUM_DIGITS);
127 }
128
129
130
131 /**
132 * Generates an HMAC-based one-time-password using the provided information.
133 *
134 * @param sharedSecret The secret key shared by both parties that will be
135 * using the generated one-time password.
136 * @param counter The counter value that will be used in the course of
137 * generating the one-time password.
138 * @param numDigits The number of digits that should be included in the
139 * generated one-time password. It must be greater than
140 * or equal to six and less than or equal to eight.
141 *
142 * @return The zero-padded string representation of the resulting HMAC-based
143 * one-time password.
144 *
145 * @throws LDAPException If an unexpected problem is encountered while
146 * attempting to generate the one-time password.
147 */
148 public static String hotp(final byte[] sharedSecret, final long counter,
149 final int numDigits)
150 throws LDAPException
151 {
152 try
153 {
154 // Ensure that the number of digits is between 6 and 8, inclusive, and
155 // get the appropriate modulus and decimal formatters to use.
156 final int modulus;
157 final DecimalFormat decimalFormat;
158 switch (numDigits)
159 {
160 case 6:
161 modulus = 1000000;
162 decimalFormat = new DecimalFormat("000000");
163 break;
164 case 7:
165 modulus = 10000000;
166 decimalFormat = new DecimalFormat("0000000");
167 break;
168 case 8:
169 modulus = 100000000;
170 decimalFormat = new DecimalFormat("00000000");
171 break;
172 default:
173 throw new LDAPException(ResultCode.PARAM_ERROR,
174 ERR_HOTP_INVALID_NUM_DIGITS.get(numDigits));
175 }
176
177
178 // Convert the provided counter to a 64-bit value.
179 final byte[] counterBytes = new byte[8];
180 counterBytes[0] = (byte) ((counter >> 56) & 0xFFL);
181 counterBytes[1] = (byte) ((counter >> 48) & 0xFFL);
182 counterBytes[2] = (byte) ((counter >> 40) & 0xFFL);
183 counterBytes[3] = (byte) ((counter >> 32) & 0xFFL);
184 counterBytes[4] = (byte) ((counter >> 24) & 0xFFL);
185 counterBytes[5] = (byte) ((counter >> 16) & 0xFFL);
186 counterBytes[6] = (byte) ((counter >> 8) & 0xFFL);
187 counterBytes[7] = (byte) (counter & 0xFFL);
188
189
190 // Generate an HMAC-SHA-1 of the given counter using the provided key.
191 final SecretKey k = new SecretKeySpec(sharedSecret, KEY_ALGORITHM_RAW);
192 final Mac m = Mac.getInstance(HMAC_ALGORITHM_SHA_1);
193 m.init(k);
194 final byte[] hmacBytes = m.doFinal(counterBytes);
195
196
197 // Generate a dynamic truncation of the resulting HMAC-SHA-1.
198 final int dtOffset = hmacBytes[19] & 0x0F;
199 final int dtValue = (((hmacBytes[dtOffset] & 0x7F) << 24) |
200 ((hmacBytes[dtOffset+1] & 0xFF) << 16) |
201 ((hmacBytes[dtOffset+2] & 0xFF) << 8) |
202 (hmacBytes[dtOffset+3] & 0xFF));
203
204
205 // Use a modulus operation to convert the value into one that has at most
206 // the desired number of digits.
207 return decimalFormat.format(dtValue % modulus);
208 }
209 catch (final Exception e)
210 {
211 Debug.debugException(e);
212 throw new LDAPException(ResultCode.LOCAL_ERROR,
213 ERR_HOTP_ERROR_GENERATING_PW.get(StaticUtils.getExceptionMessage(e)),
214 e);
215 }
216 }
217
218
219
220 /**
221 * Generates a six-digit time-based one-time-password using the provided
222 * information and a 30-second time interval.
223 *
224 * @param sharedSecret The secret key shared by both parties that will be
225 * using the generated one-time password.
226 *
227 * @return The zero-padded string representation of the resulting time-based
228 * one-time password.
229 *
230 * @throws LDAPException If an unexpected problem is encountered while
231 * attempting to generate the one-time password.
232 */
233 public static String totp(final byte[] sharedSecret)
234 throws LDAPException
235 {
236 return totp(sharedSecret, System.currentTimeMillis(),
237 DEFAULT_TOTP_INTERVAL_DURATION_SECONDS, DEFAULT_TOTP_NUM_DIGITS);
238 }
239
240
241
242 /**
243 * Generates a six-digit time-based one-time-password using the provided
244 * information.
245 *
246 * @param sharedSecret The secret key shared by both parties that
247 * will be using the generated one-time
248 * password.
249 * @param authTime The time (in milliseconds since the epoch,
250 * as reported by
251 * {@code System.currentTimeMillis} or
252 * {@code Date.getTime}) at which the
253 * authentication attempt occurred.
254 * @param intervalDurationSeconds The duration of the time interval, in
255 * seconds, that should be used when
256 * performing the computation.
257 * @param numDigits The number of digits that should be
258 * included in the generated one-time
259 * password. It must be greater than or
260 * equal to six and less than or equal to
261 * eight.
262 *
263 * @return The zero-padded string representation of the resulting time-based
264 * one-time password.
265 *
266 * @throws LDAPException If an unexpected problem is encountered while
267 * attempting to generate the one-time password.
268 */
269 public static String totp(final byte[] sharedSecret, final long authTime,
270 final int intervalDurationSeconds,
271 final int numDigits)
272 throws LDAPException
273 {
274 // Make sure that the specified number of digits is between 6 and 8,
275 // inclusive.
276 if ((numDigits < 6) || (numDigits > 8))
277 {
278 throw new LDAPException(ResultCode.PARAM_ERROR,
279 ERR_TOTP_INVALID_NUM_DIGITS.get(numDigits));
280 }
281
282 try
283 {
284 final long timeIntervalNumber = authTime / 1000 / intervalDurationSeconds;
285 return hotp(sharedSecret, timeIntervalNumber, numDigits);
286 }
287 catch (final Exception e)
288 {
289 Debug.debugException(e);
290 throw new LDAPException(ResultCode.LOCAL_ERROR,
291 ERR_TOTP_ERROR_GENERATING_PW.get(StaticUtils.getExceptionMessage(e)),
292 e);
293 }
294 }
295 }