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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.crypto.provider;
import java.security.*;
import java.security.spec.*;
import javax.crypto.*;
import javax.crypto.spec.*;
/**
* This class represents password-based encryption as defined by the PKCS #5
* standard.
*
* @author Jan Luehe
*
*
* @see javax.crypto.Cipher
*/
final class PBES1Core {
// the encapsulated DES cipher
private CipherCore cipher;
private MessageDigest md;
private int blkSize;
private String algo = null;
private byte[] salt = null;
private int iCount = 10;
/**
* Creates an instance of PBE Cipher using the specified CipherSpi
* instance.
*
*/
PBES1Core(String cipherAlg) throws NoSuchAlgorithmException,
NoSuchPaddingException {
algo = cipherAlg;
if (algo.equals("DES")) {
cipher = new CipherCore(new DESCrypt(),
DESConstants.DES_BLOCK_SIZE);
} else if (algo.equals("DESede")) {
cipher = new CipherCore(new DESedeCrypt(),
DESConstants.DES_BLOCK_SIZE);
} else {
throw new NoSuchAlgorithmException("No Cipher implementation " +
"for PBEWithMD5And" + algo);
}
cipher.setMode("CBC");
cipher.setPadding("PKCS5Padding");
// get instance of MD5
md = MessageDigest.getInstance("MD5");
}
/**
* Sets the mode of this cipher. This algorithm can only be run in CBC
* mode.
*
* @param mode the cipher mode
*
* @exception NoSuchAlgorithmException if the requested cipher mode is
* invalid
*/
void setMode(String mode) throws NoSuchAlgorithmException {
cipher.setMode(mode);
}
/**
* Sets the padding mechanism of this cipher. This algorithm only uses
* PKCS #5 padding.
*
* @param padding the padding mechanism
*
* @exception NoSuchPaddingException if the requested padding mechanism
* is invalid
*/
void setPadding(String paddingScheme) throws NoSuchPaddingException {
cipher.setPadding(paddingScheme);
}
/**
* Returns the block size (in bytes).
*
* @return the block size (in bytes)
*/
int getBlockSize() {
return DESConstants.DES_BLOCK_SIZE;
}
/**
* Returns the length in bytes that an output buffer would need to be in
* order to hold the result of the next <code>update</code> or
* <code>doFinal</code> operation, given the input length
* <code>inputLen</code> (in bytes).
*
* <p>This call takes into account any unprocessed (buffered) data from a
* previous <code>update</code> call, and padding.
*
* <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)
*
*/
int getOutputSize(int inputLen) {
return cipher.getOutputSize(inputLen);
}
/**
* Returns the initialization vector (IV) in a new buffer.
*
* <p> This is useful in the case where a random IV has been created
* (see <a href = "#init">init</a>),
* or in the context of password-based encryption or
* decryption, where the IV is derived from a user-supplied password.
*
* @return the initialization vector in a new buffer, or null if the
* underlying algorithm does not use an IV, or if the IV has not yet
* been set.
*/
byte[] getIV() {
return cipher.getIV();
}
/**
* Returns the parameters used with this cipher.
*
* <p>The returned parameters may be the same that were used to initialize
* this cipher, or may contain the default set of parameters or a set of
* randomly generated parameters used by the underlying cipher
* implementation (provided that the underlying cipher implementation
* uses a default set of parameters or creates new parameters if it needs
* parameters but was not initialized with any).
*
* @return the parameters used with this cipher, or null if this cipher
* does not use any parameters.
*/
AlgorithmParameters getParameters() {
AlgorithmParameters params = null;
if (salt == null) {
salt = new byte[8];
SunJCE.getRandom().nextBytes(salt);
}
PBEParameterSpec pbeSpec = new PBEParameterSpec(salt, iCount);
try {
params = AlgorithmParameters.getInstance("PBEWithMD5And" +
(algo.equalsIgnoreCase("DES")? "DES":"TripleDES"),
SunJCE.getInstance());
params.init(pbeSpec);
} catch (NoSuchAlgorithmException nsae) {
// should never happen
throw new RuntimeException("SunJCE called, but not configured");
} catch (InvalidParameterSpecException ipse) {
// should never happen
throw new RuntimeException("PBEParameterSpec not supported");
}
return params;
}
/**
* Initializes this cipher with a key, a set of
* algorithm parameters, and a source of randomness.
* The cipher is initialized for one of the following four operations:
* encryption, decryption, key wrapping or key unwrapping, depending on
* the value of <code>opmode</code>.
*
* <p>If this cipher (including its underlying feedback or padding scheme)
* requires any random bytes, it will get them from <code>random</code>.
*
* @param opmode the operation mode of this cipher (this is one of
* the following:
* <code>ENCRYPT_MODE</code>, <code>DECRYPT_MODE</code>),
* <code>WRAP_MODE</code> or <code>UNWRAP_MODE</code>)
* @param key the encryption key
* @param params the algorithm parameters
* @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 are inappropriate for this cipher
*/
void init(int opmode, Key key, AlgorithmParameterSpec params,
SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException {
if (((opmode == Cipher.DECRYPT_MODE) ||
(opmode == Cipher.UNWRAP_MODE)) && (params == null)) {
throw new InvalidAlgorithmParameterException("Parameters "
+ "missing");
}
if ((key == null) ||
(key.getEncoded() == null) ||
!(key.getAlgorithm().regionMatches(true, 0, "PBE", 0, 3))) {
throw new InvalidKeyException("Missing password");
}
if (params == null) {
// create random salt and use default iteration count
salt = new byte[8];
random.nextBytes(salt);
} else {
if (!(params instanceof PBEParameterSpec)) {
throw new InvalidAlgorithmParameterException
("Wrong parameter type: PBE expected");
}
salt = ((PBEParameterSpec) params).getSalt();
// salt must be 8 bytes long (by definition)
if (salt.length != 8) {
throw new InvalidAlgorithmParameterException
("Salt must be 8 bytes long");
}
iCount = ((PBEParameterSpec) params).getIterationCount();
if (iCount <= 0) {
throw new InvalidAlgorithmParameterException
("IterationCount must be a positive number");
}
}
byte[] derivedKey = deriveCipherKey(key);
// use all but the last 8 bytes as the key value
SecretKeySpec cipherKey = new SecretKeySpec(derivedKey, 0,
derivedKey.length-8, algo);
// use the last 8 bytes as the IV
IvParameterSpec ivSpec = new IvParameterSpec(derivedKey,
derivedKey.length-8,
8);
// initialize the underlying cipher
cipher.init(opmode, cipherKey, ivSpec, random);
}
private byte[] deriveCipherKey(Key key) {
byte[] result = null;
byte[] passwdBytes = key.getEncoded();
if (algo.equals("DES")) {
// P || S (password concatenated with salt)
byte[] concat = new byte[passwdBytes.length + salt.length];
System.arraycopy(passwdBytes, 0, concat, 0, passwdBytes.length);
java.util.Arrays.fill(passwdBytes, (byte)0x00);
System.arraycopy(salt, 0, concat, passwdBytes.length, salt.length);
// digest P || S with c iterations
byte[] toBeHashed = concat;
for (int i = 0; i < iCount; i++) {
md.update(toBeHashed);
toBeHashed = md.digest(); // this resets the digest
}
java.util.Arrays.fill(concat, (byte)0x00);
result = toBeHashed;
} else if (algo.equals("DESede")) {
// if the 2 salt halves are the same, invert one of them
int i;
for (i=0; i<4; i++) {
if (salt[i] != salt[i+4])
break;
}
if (i==4) { // same, invert 1st half
for (i=0; i<2; i++) {
byte tmp = salt[i];
salt[i] = salt[3-i];
salt[3-1] = tmp;
}
}
// Now digest each half (concatenated with password). For each
// half, go through the loop as many times as specified by the
// iteration count parameter (inner for loop).
// Concatenate the output from each digest round with the
// password, and use the result as the input to the next digest
// operation.
byte[] kBytes = null;
IvParameterSpec iv = null;
byte[] toBeHashed = null;
result = new byte[DESedeKeySpec.DES_EDE_KEY_LEN +
DESConstants.DES_BLOCK_SIZE];
for (i = 0; i < 2; i++) {
toBeHashed = new byte[salt.length/2];
System.arraycopy(salt, i*(salt.length/2), toBeHashed, 0,
toBeHashed.length);
for (int j=0; j < iCount; j++) {
md.update(toBeHashed);
md.update(passwdBytes);
toBeHashed = md.digest(); // this resets the digest
}
System.arraycopy(toBeHashed, 0, result, i*16,
toBeHashed.length);
}
}
return result;
}
void init(int opmode, Key key, AlgorithmParameters params,
SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException {
PBEParameterSpec pbeSpec = null;
if (params != null) {
try {
pbeSpec = params.getParameterSpec(PBEParameterSpec.class);
} catch (InvalidParameterSpecException ipse) {
throw new InvalidAlgorithmParameterException("Wrong parameter "
+ "type: PBE "
+ "expected");
}
}
init(opmode, key, pbeSpec, random);
}
/**
* Continues a multiple-part encryption or decryption operation
* (depending on how this cipher was initialized), processing another data
* part.
*
* <p>The first <code>inputLen</code> bytes in the <code>input</code>
* buffer, starting at <code>inputOffset</code>, are processed, and the
* result is stored in a new buffer.
*
* @param input the input buffer
* @param inputOffset the offset in <code>input</code> where the input
* starts
* @param inputLen the input length
*
* @return the new buffer with the result
*
*/
byte[] update(byte[] input, int inputOffset, int inputLen) {
return cipher.update(input, inputOffset, inputLen);
}
/**
* Continues a multiple-part encryption or decryption operation
* (depending on how this cipher was initialized), processing another data
* part.
*
* <p>The first <code>inputLen</code> bytes in the <code>input</code>
* buffer, starting at <code>inputOffset</code>, are processed, and the
* result is stored in the <code>output</code> buffer, starting at
* <code>outputOffset</code>.
*
* @param input the input buffer
* @param inputOffset the offset in <code>input</code> where the input
* starts
* @param inputLen the input length
* @param output the buffer for the result
* @param outputOffset the offset in <code>output</code> where the result
* is stored
*
* @return the number of bytes stored in <code>output</code>
*
* @exception ShortBufferException if the given output buffer is too small
* to hold the result
*/
int update(byte[] input, int inputOffset, int inputLen,
byte[] output, int outputOffset)
throws ShortBufferException {
return cipher.update(input, inputOffset, inputLen,
output, outputOffset);
}
/**
* Encrypts or decrypts data in a single-part operation,
* or finishes a multiple-part operation.
* The data is encrypted or decrypted, depending on how this cipher was
* initialized.
*
* <p>The first <code>inputLen</code> bytes in the <code>input</code>
* buffer, starting at <code>inputOffset</code>, and any input bytes that
* may have been buffered during a previous <code>update</code> operation,
* are processed, with padding (if requested) being applied.
* The result is stored in a new buffer.
*
* <p>The cipher is reset to its initial state (uninitialized) after this
* call.
*
* @param input the input buffer
* @param inputOffset the offset in <code>input</code> where the input
* starts
* @param inputLen the input length
*
* @return the new buffer with the result
*
* @exception IllegalBlockSizeException if this cipher is a block cipher,
* no padding has been requested (only in encryption mode), and the total
* input length of the data processed by this cipher is not a multiple of
* block size
* @exception BadPaddingException if decrypting and padding is chosen,
* but the last input data does not have proper padding bytes.
*/
byte[] doFinal(byte[] input, int inputOffset, int inputLen)
throws IllegalBlockSizeException, BadPaddingException {
return cipher.doFinal(input, inputOffset, inputLen);
}
/**
* Encrypts or decrypts data in a single-part operation,
* or finishes a multiple-part operation.
* The data is encrypted or decrypted, depending on how this cipher was
* initialized.
*
* <p>The first <code>inputLen</code> bytes in the <code>input</code>
* buffer, starting at <code>inputOffset</code>, and any input bytes that
* may have been buffered during a previous <code>update</code> operation,
* are processed, with padding (if requested) being applied.
* The result is stored in the <code>output</code> buffer, starting at
* <code>outputOffset</code>.
*
* <p>The cipher is reset to its initial state (uninitialized) after this
* call.
*
* @param input the input buffer
* @param inputOffset the offset in <code>input</code> where the input
* starts
* @param inputLen the input length
* @param output the buffer for the result
* @param outputOffset the offset in <code>output</code> where the result
* is stored
*
* @return the number of bytes stored in <code>output</code>
*
* @exception IllegalBlockSizeException if this cipher is a block cipher,
* no padding has been requested (only in encryption mode), and the total
* input length of the data processed by this cipher is not a multiple of
* block size
* @exception ShortBufferException if the given output buffer is too small
* to hold the result
* @exception BadPaddingException if decrypting and padding is chosen,
* but the last input data does not have proper padding bytes.
*/
int doFinal(byte[] input, int inputOffset, int inputLen,
byte[] output, int outputOffset)
throws ShortBufferException, IllegalBlockSizeException,
BadPaddingException {
return cipher.doFinal(input, inputOffset, inputLen,
output, outputOffset);
}
/**
* 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).
*/
byte[] wrap(Key key)
throws IllegalBlockSizeException, InvalidKeyException {
byte[] result = null;
try {
byte[] encodedKey = key.getEncoded();
if ((encodedKey == null) || (encodedKey.length == 0)) {
throw new InvalidKeyException("Cannot get an encoding of " +
"the key to be wrapped");
}
result = doFinal(encodedKey, 0, encodedKey.length);
} catch (BadPaddingException e) {
// Should never happen
}
return result;
}
/**
* 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>.
*/
Key unwrap(byte[] wrappedKey,
String wrappedKeyAlgorithm,
int wrappedKeyType)
throws InvalidKeyException, NoSuchAlgorithmException {
byte[] encodedKey;
try {
encodedKey = doFinal(wrappedKey, 0, wrappedKey.length);
} catch (BadPaddingException ePadding) {
throw new InvalidKeyException("The wrapped key is not padded " +
"correctly");
} catch (IllegalBlockSizeException eBlockSize) {
throw new InvalidKeyException("The wrapped key does not have " +
"the correct length");
}
return ConstructKeys.constructKey(encodedKey, wrappedKeyAlgorithm,
wrappedKeyType);
}
}