diff options
Diffstat (limited to 'core/src/main/java/org/bouncycastle/crypto/engines/RC2WrapEngine.java')
| -rw-r--r-- | core/src/main/java/org/bouncycastle/crypto/engines/RC2WrapEngine.java | 385 |
1 files changed, 0 insertions, 385 deletions
diff --git a/core/src/main/java/org/bouncycastle/crypto/engines/RC2WrapEngine.java b/core/src/main/java/org/bouncycastle/crypto/engines/RC2WrapEngine.java deleted file mode 100644 index ec82b1aa..00000000 --- a/core/src/main/java/org/bouncycastle/crypto/engines/RC2WrapEngine.java +++ /dev/null @@ -1,385 +0,0 @@ -package org.bouncycastle.crypto.engines; - -import java.security.SecureRandom; - -import org.bouncycastle.crypto.CipherParameters; -import org.bouncycastle.crypto.Digest; -import org.bouncycastle.crypto.InvalidCipherTextException; -import org.bouncycastle.crypto.Wrapper; -import org.bouncycastle.crypto.digests.SHA1Digest; -import org.bouncycastle.crypto.modes.CBCBlockCipher; -import org.bouncycastle.crypto.params.ParametersWithIV; -import org.bouncycastle.crypto.params.ParametersWithRandom; -import org.bouncycastle.util.Arrays; - -/** - * Wrap keys according to RFC 3217 - RC2 mechanism - */ -public class RC2WrapEngine - implements Wrapper -{ - /** Field engine */ - private CBCBlockCipher engine; - - /** Field param */ - private CipherParameters param; - - /** Field paramPlusIV */ - private ParametersWithIV paramPlusIV; - - /** Field iv */ - private byte[] iv; - - /** Field forWrapping */ - private boolean forWrapping; - - private SecureRandom sr; - - /** Field IV2 */ - private static final byte[] IV2 = { (byte) 0x4a, (byte) 0xdd, (byte) 0xa2, - (byte) 0x2c, (byte) 0x79, (byte) 0xe8, - (byte) 0x21, (byte) 0x05 }; - - // - // checksum digest - // - Digest sha1 = new SHA1Digest(); - byte[] digest = new byte[20]; - - /** - * Method init - * - * @param forWrapping - * @param param - */ - public void init(boolean forWrapping, CipherParameters param) - { - this.forWrapping = forWrapping; - this.engine = new CBCBlockCipher(new RC2Engine()); - - if (param instanceof ParametersWithRandom) - { - ParametersWithRandom pWithR = (ParametersWithRandom)param; - sr = pWithR.getRandom(); - param = pWithR.getParameters(); - } - else - { - sr = new SecureRandom(); - } - - if (param instanceof ParametersWithIV) - { - this.paramPlusIV = (ParametersWithIV)param; - this.iv = this.paramPlusIV.getIV(); - this.param = this.paramPlusIV.getParameters(); - - if (this.forWrapping) - { - if ((this.iv == null) || (this.iv.length != 8)) - { - throw new IllegalArgumentException("IV is not 8 octets"); - } - } - else - { - throw new IllegalArgumentException( - "You should not supply an IV for unwrapping"); - } - } - else - { - this.param = param; - - if (this.forWrapping) - { - - // Hm, we have no IV but we want to wrap ?!? - // well, then we have to create our own IV. - this.iv = new byte[8]; - - sr.nextBytes(iv); - - this.paramPlusIV = new ParametersWithIV(this.param, this.iv); - } - } - - } - - /** - * Method getAlgorithmName - * - * @return the algorithm name "RC2". - */ - public String getAlgorithmName() - { - return "RC2"; - } - - /** - * Method wrap - * - * @param in - * @param inOff - * @param inLen - * @return the wrapped bytes. - */ - public byte[] wrap(byte[] in, int inOff, int inLen) - { - - if (!forWrapping) - { - throw new IllegalStateException("Not initialized for wrapping"); - } - - int length = inLen + 1; - if ((length % 8) != 0) - { - length += 8 - (length % 8); - } - - byte keyToBeWrapped[] = new byte[length]; - - keyToBeWrapped[0] = (byte)inLen; - System.arraycopy(in, inOff, keyToBeWrapped, 1, inLen); - - byte[] pad = new byte[keyToBeWrapped.length - inLen - 1]; - - if (pad.length > 0) - { - sr.nextBytes(pad); - System.arraycopy(pad, 0, keyToBeWrapped, inLen + 1, pad.length); - } - - // Compute the CMS Key Checksum, (section 5.6.1), call this CKS. - byte[] CKS = calculateCMSKeyChecksum(keyToBeWrapped); - - // Let WKCKS = WK || CKS where || is concatenation. - byte[] WKCKS = new byte[keyToBeWrapped.length + CKS.length]; - - System.arraycopy(keyToBeWrapped, 0, WKCKS, 0, keyToBeWrapped.length); - System.arraycopy(CKS, 0, WKCKS, keyToBeWrapped.length, CKS.length); - - // Encrypt WKCKS in CBC mode using KEK as the key and IV as the - // initialization vector. Call the results TEMP1. - byte TEMP1[] = new byte[WKCKS.length]; - - System.arraycopy(WKCKS, 0, TEMP1, 0, WKCKS.length); - - int noOfBlocks = WKCKS.length / engine.getBlockSize(); - int extraBytes = WKCKS.length % engine.getBlockSize(); - - if (extraBytes != 0) - { - throw new IllegalStateException("Not multiple of block length"); - } - - engine.init(true, paramPlusIV); - - for (int i = 0; i < noOfBlocks; i++) - { - int currentBytePos = i * engine.getBlockSize(); - - engine.processBlock(TEMP1, currentBytePos, TEMP1, currentBytePos); - } - - // Left TEMP2 = IV || TEMP1. - byte[] TEMP2 = new byte[this.iv.length + TEMP1.length]; - - System.arraycopy(this.iv, 0, TEMP2, 0, this.iv.length); - System.arraycopy(TEMP1, 0, TEMP2, this.iv.length, TEMP1.length); - - // Reverse the order of the octets in TEMP2 and call the result TEMP3. - byte[] TEMP3 = new byte[TEMP2.length]; - - for (int i = 0; i < TEMP2.length; i++) - { - TEMP3[i] = TEMP2[TEMP2.length - (i + 1)]; - } - - // Encrypt TEMP3 in CBC mode using the KEK and an initialization vector - // of 0x 4a dd a2 2c 79 e8 21 05. The resulting cipher text is the - // desired - // result. It is 40 octets long if a 168 bit key is being wrapped. - ParametersWithIV param2 = new ParametersWithIV(this.param, IV2); - - this.engine.init(true, param2); - - for (int i = 0; i < noOfBlocks + 1; i++) - { - int currentBytePos = i * engine.getBlockSize(); - - engine.processBlock(TEMP3, currentBytePos, TEMP3, currentBytePos); - } - - return TEMP3; - } - - /** - * Method unwrap - * - * @param in - * @param inOff - * @param inLen - * @return the unwrapped bytes. - * @throws InvalidCipherTextException - */ - public byte[] unwrap(byte[] in, int inOff, int inLen) - throws InvalidCipherTextException - { - - if (forWrapping) - { - throw new IllegalStateException("Not set for unwrapping"); - } - - if (in == null) - { - throw new InvalidCipherTextException("Null pointer as ciphertext"); - } - - if (inLen % engine.getBlockSize() != 0) - { - throw new InvalidCipherTextException("Ciphertext not multiple of " - + engine.getBlockSize()); - } - - /* - * // Check if the length of the cipher text is reasonable given the key // - * type. It must be 40 bytes for a 168 bit key and either 32, 40, or // - * 48 bytes for a 128, 192, or 256 bit key. If the length is not - * supported // or inconsistent with the algorithm for which the key is - * intended, // return error. // // we do not accept 168 bit keys. it - * has to be 192 bit. int lengthA = (estimatedKeyLengthInBit / 8) + 16; - * int lengthB = estimatedKeyLengthInBit % 8; - * - * if ((lengthA != keyToBeUnwrapped.length) || (lengthB != 0)) { throw - * new XMLSecurityException("empty"); } - */ - - // Decrypt the cipher text with TRIPLedeS in CBC mode using the KEK - // and an initialization vector (IV) of 0x4adda22c79e82105. Call the - // output TEMP3. - ParametersWithIV param2 = new ParametersWithIV(this.param, IV2); - - this.engine.init(false, param2); - - byte TEMP3[] = new byte[inLen]; - - System.arraycopy(in, inOff, TEMP3, 0, inLen); - - for (int i = 0; i < (TEMP3.length / engine.getBlockSize()); i++) - { - int currentBytePos = i * engine.getBlockSize(); - - engine.processBlock(TEMP3, currentBytePos, TEMP3, currentBytePos); - } - - // Reverse the order of the octets in TEMP3 and call the result TEMP2. - byte[] TEMP2 = new byte[TEMP3.length]; - - for (int i = 0; i < TEMP3.length; i++) - { - TEMP2[i] = TEMP3[TEMP3.length - (i + 1)]; - } - - // Decompose TEMP2 into IV, the first 8 octets, and TEMP1, the remaining - // octets. - this.iv = new byte[8]; - - byte[] TEMP1 = new byte[TEMP2.length - 8]; - - System.arraycopy(TEMP2, 0, this.iv, 0, 8); - System.arraycopy(TEMP2, 8, TEMP1, 0, TEMP2.length - 8); - - // Decrypt TEMP1 using TRIPLedeS in CBC mode using the KEK and the IV - // found in the previous step. Call the result WKCKS. - this.paramPlusIV = new ParametersWithIV(this.param, this.iv); - - this.engine.init(false, this.paramPlusIV); - - byte[] LCEKPADICV = new byte[TEMP1.length]; - - System.arraycopy(TEMP1, 0, LCEKPADICV, 0, TEMP1.length); - - for (int i = 0; i < (LCEKPADICV.length / engine.getBlockSize()); i++) - { - int currentBytePos = i * engine.getBlockSize(); - - engine.processBlock(LCEKPADICV, currentBytePos, LCEKPADICV, - currentBytePos); - } - - // Decompose LCEKPADICV. CKS is the last 8 octets and WK, the wrapped - // key, are - // those octets before the CKS. - byte[] result = new byte[LCEKPADICV.length - 8]; - byte[] CKStoBeVerified = new byte[8]; - - System.arraycopy(LCEKPADICV, 0, result, 0, LCEKPADICV.length - 8); - System.arraycopy(LCEKPADICV, LCEKPADICV.length - 8, CKStoBeVerified, 0, - 8); - - // Calculate a CMS Key Checksum, (section 5.6.1), over the WK and - // compare - // with the CKS extracted in the above step. If they are not equal, - // return error. - if (!checkCMSKeyChecksum(result, CKStoBeVerified)) - { - throw new InvalidCipherTextException( - "Checksum inside ciphertext is corrupted"); - } - - if ((result.length - ((result[0] & 0xff) + 1)) > 7) - { - throw new InvalidCipherTextException("too many pad bytes (" - + (result.length - ((result[0] & 0xff) + 1)) + ")"); - } - - // CEK is the wrapped key, now extracted for use in data decryption. - byte[] CEK = new byte[result[0]]; - System.arraycopy(result, 1, CEK, 0, CEK.length); - return CEK; - } - - /** - * Some key wrap algorithms make use of the Key Checksum defined - * in CMS [CMS-Algorithms]. This is used to provide an integrity - * check value for the key being wrapped. The algorithm is - * - * - Compute the 20 octet SHA-1 hash on the key being wrapped. - * - Use the first 8 octets of this hash as the checksum value. - * - * For details see http://www.w3.org/TR/xmlenc-core/#sec-CMSKeyChecksum - * @param key - * @return - * @throws RuntimeException - * - */ - private byte[] calculateCMSKeyChecksum( - byte[] key) - { - byte[] result = new byte[8]; - - sha1.update(key, 0, key.length); - sha1.doFinal(digest, 0); - - System.arraycopy(digest, 0, result, 0, 8); - - return result; - } - - /** - * For details see http://www.w3.org/TR/xmlenc-core/#sec-CMSKeyChecksum - * - * @param key - * @param checksum - * @return - */ - private boolean checkCMSKeyChecksum( - byte[] key, - byte[] checksum) - { - return Arrays.constantTimeAreEqual(calculateCMSKeyChecksum(key), checksum); - } -} |