jdk/src/share/classes/com/sun/crypto/provider/AESWrapCipher.java
changeset 2 90ce3da70b43
child 3353 ddbd63234844
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/com/sun/crypto/provider/AESWrapCipher.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,487 @@
+/*
+ * Copyright 2004-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package com.sun.crypto.provider;
+
+import java.util.Arrays;
+import java.security.*;
+import java.security.spec.*;
+import javax.crypto.*;
+import javax.crypto.spec.*;
+
+/**
+ * This class implements the AES KeyWrap algorithm as defined
+ * in <a href=http://www.w3.org/TR/xmlenc-core/#sec-Alg-SymmetricKeyWrap>
+ * "XML Encryption Syntax and Processing" section 5.6.3 "AES Key Wrap".
+ * Note: only <code>ECB</code> mode and <code>NoPadding</code> padding
+ * can be used for this algorithm.
+ *
+ * @author Valerie Peng
+ *
+ *
+ * @see AESCipher
+ */
+public final class AESWrapCipher extends CipherSpi {
+
+    private static final byte[] IV = {
+        (byte) 0xA6, (byte) 0xA6, (byte) 0xA6, (byte) 0xA6,
+        (byte) 0xA6, (byte) 0xA6, (byte) 0xA6, (byte) 0xA6
+    };
+
+    private static final int blksize = AESConstants.AES_BLOCK_SIZE;
+
+    /*
+     * internal cipher object which does the real work.
+     */
+    private AESCrypt cipher;
+
+    /*
+     * are we encrypting or decrypting?
+     */
+    private boolean decrypting = false;
+
+    /**
+     * Creates an instance of AES KeyWrap cipher with default
+     * mode, i.e. "ECB" and padding scheme, i.e. "NoPadding".
+     *
+     * @exception SecurityException if this constructor fails to verify
+     * its own integrity
+     */
+    public AESWrapCipher() {
+        SunJCE.ensureIntegrity(getClass());
+        cipher = new AESCrypt();
+    }
+
+    /**
+     * Sets the mode of this cipher. Only "ECB" mode is accepted for this
+     * cipher.
+     *
+     * @param mode the cipher mode
+     *
+     * @exception NoSuchAlgorithmException if the requested cipher mode
+     * is not "ECB".
+     */
+    protected void engineSetMode(String mode)
+        throws NoSuchAlgorithmException {
+        if (!mode.equalsIgnoreCase("ECB")) {
+            throw new NoSuchAlgorithmException(mode + " cannot be used");
+        }
+    }
+
+    /**
+     * Sets the padding mechanism of this cipher. Only "NoPadding" schmem
+     * is accepted for this cipher.
+     *
+     * @param padding the padding mechanism
+     *
+     * @exception NoSuchPaddingException if the requested padding mechanism
+     * is not "NoPadding".
+     */
+    protected void engineSetPadding(String padding)
+        throws NoSuchPaddingException {
+        if (!padding.equalsIgnoreCase("NoPadding")) {
+            throw new NoSuchPaddingException(padding + " cannot be used");
+        }
+    }
+
+    /**
+     * Returns the block size (in bytes). i.e. 16 bytes.
+     *
+     * @return the block size (in bytes), i.e. 16 bytes.
+     */
+    protected int engineGetBlockSize() {
+        return blksize;
+    }
+
+    /**
+     * Returns the length in bytes that an output buffer would need to be
+     * given the input length <code>inputLen</code> (in bytes).
+     *
+     * <p>The actual output length of the next <code>update</code> or
+     * <code>doFinal</code> call may be smaller than the length returned
+     * by this method.
+     *
+     * @param inputLen the input length (in bytes)
+     *
+     * @return the required output buffer size (in bytes)
+     */
+    protected int engineGetOutputSize(int inputLen) {
+        // can only return an upper-limit if not initialized yet.
+        int result = 0;
+        if (decrypting) {
+            result = inputLen - 8;
+        } else {
+            result = inputLen + 8;
+        }
+        return (result < 0? 0:result);
+    }
+
+    /**
+     * Returns the initialization vector (IV) which is null for this cipher.
+     *
+     * @return null for this cipher.
+     */
+    protected byte[] engineGetIV() {
+        return null;
+    }
+
+    /**
+     * Initializes this cipher with a key and a source of randomness.
+     *
+     * <p>The cipher only supports the following two operation modes:<b>
+     * Cipher.WRAP_MODE, and <b>
+     * Cipher.UNWRAP_MODE.
+     * <p>For modes other than the above two, UnsupportedOperationException
+     * will be thrown.
+     *
+     * @param opmode the operation mode of this cipher. Only
+     * <code>WRAP_MODE</code> or <code>UNWRAP_MODE</code>) are accepted.
+     * @param key the secret key.
+     * @param random the source of randomness.
+     *
+     * @exception InvalidKeyException if the given key is inappropriate for
+     * initializing this cipher.
+     */
+    protected void engineInit(int opmode, Key key, SecureRandom random)
+        throws InvalidKeyException {
+        if (opmode == Cipher.WRAP_MODE) {
+            decrypting = false;
+        } else if (opmode == Cipher.UNWRAP_MODE) {
+            decrypting = true;
+        } else {
+            throw new UnsupportedOperationException("This cipher can " +
+                "only be used for key wrapping and unwrapping");
+        }
+        cipher.init(decrypting, key.getAlgorithm(), key.getEncoded());
+    }
+
+    /**
+     * Initializes this cipher with a key, a set of algorithm parameters,
+     * and a source of randomness.
+     *
+     * <p>The cipher only supports the following two operation modes:<b>
+     * Cipher.WRAP_MODE, and <b>
+     * Cipher.UNWRAP_MODE.
+     * <p>For modes other than the above two, UnsupportedOperationException
+     * will be thrown.
+     *
+     * @param opmode the operation mode of this cipher. Only
+     * <code>WRAP_MODE</code> or <code>UNWRAP_MODE</code>) are accepted.
+     * @param key the secret key.
+     * @param params the algorithm parameters; must be null for this cipher.
+     * @param random the source of randomness.
+     *
+     * @exception InvalidKeyException if the given key is inappropriate for
+     * initializing this cipher
+     * @exception InvalidAlgorithmParameterException if the given algorithm
+     * parameters is not null.
+     */
+    protected void engineInit(int opmode, Key key,
+                              AlgorithmParameterSpec params,
+                              SecureRandom random)
+        throws InvalidKeyException, InvalidAlgorithmParameterException {
+        if (params != null) {
+            throw new InvalidAlgorithmParameterException("This cipher " +
+                "does not accept any parameters");
+        }
+        engineInit(opmode, key, random);
+    }
+
+    /**
+     * Initializes this cipher with a key, a set of algorithm parameters,
+     * and a source of randomness.
+     *
+     * <p>The cipher only supports the following two operation modes:<b>
+     * Cipher.WRAP_MODE, and <b>
+     * Cipher.UNWRAP_MODE.
+     * <p>For modes other than the above two, UnsupportedOperationException
+     * will be thrown.
+     *
+     * @param opmode the operation mode of this cipher. Only
+     * <code>WRAP_MODE</code> or <code>UNWRAP_MODE</code>) are accepted.
+     * @param key the secret key.
+     * @param params the algorithm parameters; must be null for this cipher.
+     * @param random the source of randomness.
+     *
+     * @exception InvalidKeyException if the given key is inappropriate.
+     * @exception InvalidAlgorithmParameterException if the given algorithm
+     * parameters is not null.
+     */
+    protected void engineInit(int opmode, Key key,
+                              AlgorithmParameters params,
+                              SecureRandom random)
+        throws InvalidKeyException, InvalidAlgorithmParameterException {
+        if (params != null) {
+            throw new InvalidAlgorithmParameterException("This cipher " +
+                "does not accept any parameters");
+        }
+        engineInit(opmode, key, random);
+    }
+
+    /**
+     * This operation is not supported by this cipher.
+     * Since it's impossible to initialize this cipher given the
+     * current Cipher.engineInit(...) implementation,
+     * IllegalStateException will always be thrown upon invocation.
+     *
+     * @param in the input buffer.
+     * @param inOffset the offset in <code>in</code> where the input
+     * starts.
+     * @param inLen the input length.
+     *
+     * @return n/a.
+     *
+     * @exception IllegalStateException upon invocation of this method.
+     */
+    protected byte[] engineUpdate(byte[] in, int inOffset, int inLen) {
+        throw new IllegalStateException("Cipher has not been initialized");
+    }
+
+    /**
+     * This operation is not supported by this cipher.
+     * Since it's impossible to initialize this cipher given the
+     * current Cipher.engineInit(...) implementation,
+     * IllegalStateException will always be thrown upon invocation.
+     *
+     * @param in the input buffer.
+     * @param inOffset the offset in <code>in</code> where the input
+     * starts.
+     * @param inLen the input length.
+     * @param out the buffer for the result.
+     * @param outOffset the offset in <code>out</code> where the result
+     * is stored.
+     *
+     * @return n/a.
+     *
+     * @exception IllegalStateException upon invocation of this method.
+     */
+    protected int engineUpdate(byte[] in, int inOffset, int inLen,
+                               byte[] out, int outOffset)
+        throws ShortBufferException {
+        throw new IllegalStateException("Cipher has not been initialized");
+    }
+
+    /**
+     * This operation is not supported by this cipher.
+     * Since it's impossible to initialize this cipher given the
+     * current Cipher.engineInit(...) implementation,
+     * IllegalStateException will always be thrown upon invocation.
+     *
+     * @param in the input buffer
+     * @param inOffset the offset in <code>in</code> where the input
+     * starts
+     * @param inLen the input length.
+     *
+     * @return n/a.
+     *
+     * @exception IllegalStateException upon invocation of this method.
+     */
+    protected byte[] engineDoFinal(byte[] input, int inputOffset,
+                                   int inputLen)
+        throws IllegalBlockSizeException, BadPaddingException {
+        throw new IllegalStateException("Cipher has not been initialized");
+    }
+
+    /**
+     * This operation is not supported by this cipher.
+     * Since it's impossible to initialize this cipher given the
+     * current Cipher.engineInit(...) implementation,
+     * IllegalStateException will always be thrown upon invocation.
+     *
+     * @param in the input buffer.
+     * @param inOffset the offset in <code>in</code> where the input
+     * starts.
+     * @param inLen the input length.
+     * @param out the buffer for the result.
+     * @param outOffset the ofset in <code>out</code> where the result
+     * is stored.
+     *
+     * @return n/a.
+     *
+     * @exception IllegalStateException upon invocation of this method.
+     */
+    protected int engineDoFinal(byte[] in, int inOffset, int inLen,
+                                byte[] out, int outOffset)
+        throws IllegalBlockSizeException, ShortBufferException,
+               BadPaddingException {
+        throw new IllegalStateException("Cipher has not been initialized");
+    }
+
+    /**
+     * Returns the parameters used with this cipher which is always null
+     * for this cipher.
+     *
+     * @return null since this cipher does not use any parameters.
+     */
+    protected AlgorithmParameters engineGetParameters() {
+        return null;
+    }
+
+    /**
+     * Returns the key size of the given key object in number of bits.
+     *
+     * @param key the key object.
+     *
+     * @return the "effective" key size of the given key object.
+     *
+     * @exception InvalidKeyException if <code>key</code> is invalid.
+     */
+    protected int engineGetKeySize(Key key) throws InvalidKeyException {
+        byte[] encoded = key.getEncoded();
+        if (!AESCrypt.isKeySizeValid(encoded.length)) {
+            throw new InvalidKeyException("Invalid key length: " +
+                                          encoded.length + " bytes");
+        }
+        return encoded.length * 8;
+    }
+
+    /**
+     * Wrap a key.
+     *
+     * @param key the key to be wrapped.
+     *
+     * @return the wrapped key.
+     *
+     * @exception IllegalBlockSizeException if this cipher is a block
+     * cipher, no padding has been requested, and the length of the
+     * encoding of the key to be wrapped is not a
+     * multiple of the block size.
+     *
+     * @exception InvalidKeyException if it is impossible or unsafe to
+     * wrap the key with this cipher (e.g., a hardware protected key is
+     * being passed to a software only cipher).
+     */
+    protected byte[] engineWrap(Key key)
+        throws IllegalBlockSizeException, InvalidKeyException {
+        byte[] keyVal = key.getEncoded();
+        if ((keyVal == null) || (keyVal.length == 0)) {
+            throw new InvalidKeyException("Cannot get an encoding of " +
+                                          "the key to be wrapped");
+        }
+        byte[] out = new byte[keyVal.length + 8];
+
+        if (keyVal.length == 8) {
+            System.arraycopy(IV, 0, out, 0, IV.length);
+            System.arraycopy(keyVal, 0, out, IV.length, 8);
+            cipher.encryptBlock(out, 0, out, 0);
+        } else {
+            if (keyVal.length % 8 != 0) {
+                throw new IllegalBlockSizeException("length of the " +
+                    "to be wrapped key should be multiples of 8 bytes");
+            }
+            System.arraycopy(IV, 0, out, 0, IV.length);
+            System.arraycopy(keyVal, 0, out, IV.length, keyVal.length);
+            int N = keyVal.length/8;
+            byte[] buffer = new byte[blksize];
+            for (int j = 0; j < 6; j++) {
+                for (int i = 1; i <= N; i++) {
+                    int T = i + j*N;
+                    System.arraycopy(out, 0, buffer, 0, IV.length);
+                    System.arraycopy(out, i*8, buffer, IV.length, 8);
+                    cipher.encryptBlock(buffer, 0, buffer, 0);
+                    for (int k = 1; T != 0; k++) {
+                        byte v = (byte) T;
+                        buffer[IV.length - k] ^= v;
+                        T >>>= 8;
+                    }
+                    System.arraycopy(buffer, 0, out, 0, IV.length);
+                    System.arraycopy(buffer, 8, out, 8*i, 8);
+                }
+            }
+        }
+        return out;
+    }
+
+    /**
+     * Unwrap a previously wrapped key.
+     *
+     * @param wrappedKey the key to be unwrapped.
+     *
+     * @param wrappedKeyAlgorithm the algorithm the wrapped key is for.
+     *
+     * @param wrappedKeyType the type of the wrapped key.
+     * This is one of <code>Cipher.SECRET_KEY</code>,
+     * <code>Cipher.PRIVATE_KEY</code>, or <code>Cipher.PUBLIC_KEY</code>.
+     *
+     * @return the unwrapped key.
+     *
+     * @exception NoSuchAlgorithmException if no installed providers
+     * can create keys of type <code>wrappedKeyType</code> for the
+     * <code>wrappedKeyAlgorithm</code>.
+     *
+     * @exception InvalidKeyException if <code>wrappedKey</code> does not
+     * represent a wrapped key of type <code>wrappedKeyType</code> for
+     * the <code>wrappedKeyAlgorithm</code>.
+     */
+    protected Key engineUnwrap(byte[] wrappedKey,
+                               String wrappedKeyAlgorithm,
+                               int wrappedKeyType)
+        throws InvalidKeyException, NoSuchAlgorithmException {
+        int wrappedKeyLen = wrappedKey.length;
+        // ensure the wrappedKey length is multiples of 8 bytes and non-zero
+        if (wrappedKeyLen == 0) {
+            throw new InvalidKeyException("The wrapped key is empty");
+        }
+        if (wrappedKeyLen % 8 != 0) {
+            throw new InvalidKeyException
+                ("The wrapped key has invalid key length");
+        }
+        byte[] out = new byte[wrappedKeyLen - 8];
+        byte[] buffer = new byte[blksize];
+        if (wrappedKeyLen == 16) {
+            cipher.decryptBlock(wrappedKey, 0, buffer, 0);
+            for (int i = 0; i < IV.length; i++) {
+                if (IV[i] != buffer[i]) {
+                    throw new InvalidKeyException("Integrity check failed");
+                }
+            }
+            System.arraycopy(buffer, IV.length, out, 0, out.length);
+        } else {
+            System.arraycopy(wrappedKey, 0, buffer, 0, IV.length);
+            System.arraycopy(wrappedKey, IV.length, out, 0, out.length);
+            int N = out.length/8;
+            for (int j = 5; j >= 0; j--) {
+                for (int i = N; i > 0; i--) {
+                    int T = i + j*N;
+                    System.arraycopy(out, 8*(i-1), buffer, IV.length, 8);
+                    for (int k = 1; T != 0; k++) {
+                        byte v = (byte) T;
+                        buffer[IV.length - k] ^= v;
+                        T >>>= 8;
+                    }
+                    cipher.decryptBlock(buffer, 0, buffer, 0);
+                    System.arraycopy(buffer, IV.length, out, 8*(i-1), 8);
+                }
+            }
+            for (int i = 0; i < IV.length; i++) {
+                if (IV[i] != buffer[i]) {
+                    throw new InvalidKeyException("Integrity check failed");
+                }
+            }
+        }
+        return ConstructKeys.constructKey(out, wrappedKeyAlgorithm,
+                                          wrappedKeyType);
+    }
+}