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Diffstat (limited to 'libjava/classpath/gnu/javax/crypto/mode/ModeFactory.java')
| -rw-r--r-- | libjava/classpath/gnu/javax/crypto/mode/ModeFactory.java | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/libjava/classpath/gnu/javax/crypto/mode/ModeFactory.java b/libjava/classpath/gnu/javax/crypto/mode/ModeFactory.java new file mode 100644 index 00000000000..0e949ed9e96 --- /dev/null +++ b/libjava/classpath/gnu/javax/crypto/mode/ModeFactory.java @@ -0,0 +1,192 @@ +/* ModeFactory.java -- + Copyright (C) 2001, 2002, 2004, 2006 Free Software Foundation, Inc. + +This file is a part of GNU Classpath. + +GNU Classpath 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 Classpath 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 GNU Classpath; if not, write to the Free Software +Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 +USA + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package gnu.javax.crypto.mode; + +import gnu.java.security.Registry; + +import gnu.javax.crypto.cipher.CipherFactory; +import gnu.javax.crypto.cipher.IBlockCipher; + +import java.util.Collections; +import java.util.HashSet; +import java.util.Iterator; +import java.util.Set; + +/** + * <p>A <i>Factory</i> to instantiate block cipher modes of operations.</p> + */ +public class ModeFactory implements Registry +{ + + // Constants and variables + // ------------------------------------------------------------------------- + + // Constructor(s) + // ------------------------------------------------------------------------- + + /** Trivial constructor to enforce Singleton pattern. */ + private ModeFactory() + { + super(); + } + + // Class methods + // ------------------------------------------------------------------------- + + /** + * <p>Returns an instance of a block cipher mode of operations given its name + * and characteristics of the underlying block cipher.</p> + * + * @param mode the case-insensitive name of the mode of operations. + * @param cipher the case-insensitive name of the block cipher. + * @param cipherBlockSize the block size, in bytes, of the underlying cipher. + * @return an instance of the block cipher algorithm, operating in a given + * mode of operations, or <code>null</code> if none found. + * @exception InternalError if either the mode or the underlying block cipher + * implementation does not pass its self-test. + */ + public static IMode getInstance(String mode, String cipher, + int cipherBlockSize) + { + if (mode == null || cipher == null) + { + return null; + } + + mode = mode.trim(); + cipher = cipher.trim(); + + IBlockCipher cipherImpl = CipherFactory.getInstance(cipher); + if (cipherImpl == null) + { + return null; + } + + return getInstance(mode, cipherImpl, cipherBlockSize); + } + + public static IMode getInstance(String mode, IBlockCipher cipher, + int cipherBlockSize) + { + // ensure that cipherBlockSize is valid for the chosen underlying cipher + boolean ok = false; + for (Iterator it = cipher.blockSizes(); it.hasNext();) + { + ok = (cipherBlockSize == ((Integer) it.next()).intValue()); + if (ok) + { + break; + } + } + + if (!ok) + { + throw new IllegalArgumentException("cipherBlockSize"); + } + + IMode result = null; + if (mode.equalsIgnoreCase(ECB_MODE)) + { + result = new ECB(cipher, cipherBlockSize); + } + else if (mode.equalsIgnoreCase(CTR_MODE)) + { + result = new CTR(cipher, cipherBlockSize); + } + else if (mode.equalsIgnoreCase(ICM_MODE)) + { + result = new ICM(cipher, cipherBlockSize); + } + else if (mode.equalsIgnoreCase(OFB_MODE)) + { + result = new OFB(cipher, cipherBlockSize); + } + else if (mode.equalsIgnoreCase(CBC_MODE)) + { + result = new CBC(cipher, cipherBlockSize); + } + else if (mode.equalsIgnoreCase(CFB_MODE)) + { + result = new CFB(cipher, cipherBlockSize); + } + else if (mode.equalsIgnoreCase(EAX_MODE)) + { + result = new EAX(cipher, cipherBlockSize); + } + + if (result != null && !result.selfTest()) + { + throw new InternalError(result.name()); + } + + return result; + } + + /** + * <p>Returns a {@link java.util.Set} of names of mode supported by this + * <i>Factory</i>.</p> + * + * @return a {@link java.util.Set} of mode names (Strings). + */ + public static final Set getNames() + { + synchronized (ModeFactory.class) + { + if (names == null) + { + HashSet hs = new HashSet(); + hs.add(ECB_MODE); + hs.add(CTR_MODE); + hs.add(ICM_MODE); + hs.add(OFB_MODE); + hs.add(CBC_MODE); + hs.add(CFB_MODE); + hs.add(EAX_MODE); + + names = Collections.unmodifiableSet(hs); + } + } + return names; + } + + private static Set names; + + // Instance methods + // ------------------------------------------------------------------------- +}
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