/**
* Method init
*
* @param forWrapping
* @param param
*/
public void Init(
bool forWrapping,
ICipherParameters parameters)
{
this.forWrapping = forWrapping;
this.engine = new CbcBlockCipher(new DesEdeEngine());
SecureRandom sr;
if (parameters is ParametersWithRandom)
{
ParametersWithRandom pr = (ParametersWithRandom) parameters;
parameters = pr.Parameters;
sr = pr.Random;
}
else
{
sr = new SecureRandom();
}
if (parameters is KeyParameter)
{
this.param = (KeyParameter) parameters;
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);
}
}
else if (parameters is ParametersWithIV)
{
if (!forWrapping)
throw new ArgumentException("You should not supply an IV for unwrapping");
this.paramPlusIV = (ParametersWithIV) parameters;
this.iv = this.paramPlusIV.GetIV();
this.param = (KeyParameter) this.paramPlusIV.Parameters;
if (this.iv.Length != 8)
throw new ArgumentException("IV is not 8 octets", "parameters");
}
}
public void Init(
bool forWrapping,
ICipherParameters param)
{
this.forWrapping = forWrapping;
if (param is ParametersWithRandom)
{
ParametersWithRandom p = (ParametersWithRandom) param;
this.rand = p.Random;
this.param = (ParametersWithIV) p.Parameters;
}
else
{
if (forWrapping)
{
rand = new SecureRandom();
}
this.param = (ParametersWithIV) param;
}
}
/**
* Method unwrap
*
* @param in
* @param inOff
* @param inLen
* @return
* @throws InvalidCipherTextException
*/
public byte[] Unwrap(
byte[] input,
int inOff,
int length)
{
if (forWrapping)
{
throw new InvalidOperationException("Not set for unwrapping");
}
if (input == null)
{
throw new InvalidCipherTextException("Null pointer as ciphertext");
}
if (length % 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.parameters, IV2);
this.engine.Init(false, param2);
byte [] TEMP3 = new byte[length];
Array.Copy(input, inOff, TEMP3, 0, length);
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];
Array.Copy(TEMP2, 0, this.iv, 0, 8);
Array.Copy(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.parameters, this.iv);
this.engine.Init(false, this.paramPlusIV);
byte[] LCEKPADICV = new byte[TEMP1.Length];
Array.Copy(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];
Array.Copy(LCEKPADICV, 0, result, 0, LCEKPADICV.Length - 8);
Array.Copy(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]];
Array.Copy(result, 1, CEK, 0, CEK.Length);
return CEK;
}
/**
* Method wrap
*
* @param in
* @param inOff
* @param inLen
* @return
*/
public byte[] Wrap(
byte[] input,
int inOff,
int length)
{
if (!forWrapping)
{
throw new InvalidOperationException("Not initialized for wrapping");
}
int len = length + 1;
if ((len % 8) != 0)
{
len += 8 - (len % 8);
}
byte [] keyToBeWrapped = new byte[len];
keyToBeWrapped[0] = (byte)length;
Array.Copy(input, inOff, keyToBeWrapped, 1, length);
byte[] pad = new byte[keyToBeWrapped.Length - length - 1];
if (pad.Length > 0)
{
sr.NextBytes(pad);
Array.Copy(pad, 0, keyToBeWrapped, length + 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];
Array.Copy(keyToBeWrapped, 0, WKCKS, 0, keyToBeWrapped.Length);
Array.Copy(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];
Array.Copy(WKCKS, 0, TEMP1, 0, WKCKS.Length);
int noOfBlocks = WKCKS.Length / engine.GetBlockSize();
int extraBytes = WKCKS.Length % engine.GetBlockSize();
if (extraBytes != 0)
{
throw new InvalidOperationException("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];
Array.Copy(this.iv, 0, TEMP2, 0, this.iv.Length);
Array.Copy(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.parameters, 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 wrap
*
* @param in
* @param inOff
* @param inLen
* @return
*/
public byte[] Wrap(
byte[] input,
int inOff,
int length)
{
if (!forWrapping)
{
throw new InvalidOperationException("Not initialized for wrapping");
}
byte[] keyToBeWrapped = new byte[length];
Array.Copy(input, inOff, keyToBeWrapped, 0, 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];
Array.Copy(keyToBeWrapped, 0, WKCKS, 0, keyToBeWrapped.Length);
Array.Copy(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.
int blockSize = engine.GetBlockSize();
if (WKCKS.Length % blockSize != 0)
throw new InvalidOperationException("Not multiple of block length");
engine.Init(true, paramPlusIV);
byte [] TEMP1 = new byte[WKCKS.Length];
for (int currentBytePos = 0; currentBytePos != WKCKS.Length; currentBytePos += blockSize)
{
engine.ProcessBlock(WKCKS, currentBytePos, TEMP1, currentBytePos);
}
// Let TEMP2 = IV || TEMP1.
byte[] TEMP2 = new byte[this.iv.Length + TEMP1.Length];
Array.Copy(this.iv, 0, TEMP2, 0, this.iv.Length);
Array.Copy(TEMP1, 0, TEMP2, this.iv.Length, TEMP1.Length);
// Reverse the order of the octets in TEMP2 and call the result TEMP3.
byte[] TEMP3 = reverse(TEMP2);
// 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 currentBytePos = 0; currentBytePos != TEMP3.Length; currentBytePos += blockSize)
{
engine.ProcessBlock(TEMP3, currentBytePos, TEMP3, currentBytePos);
}
return TEMP3;
}
public static ICipherParameters GenerateCipherParameters(
string algorithm,
char[] password,
bool wrongPkcs12Zero,
Asn1Encodable pbeParameters)
{
string mechanism = (string)algorithms[Platform.ToUpperInvariant(algorithm)];
byte[] keyBytes = null;
byte[] salt = null;
int iterationCount = 0;
if (IsPkcs12(mechanism))
{
Pkcs12PbeParams pbeParams = Pkcs12PbeParams.GetInstance(pbeParameters);
salt = pbeParams.GetIV();
iterationCount = pbeParams.Iterations.IntValue;
keyBytes = PbeParametersGenerator.Pkcs12PasswordToBytes(password, wrongPkcs12Zero);
}
else if (IsPkcs5Scheme2(mechanism))
{
// See below
}
else
{
PbeParameter pbeParams = PbeParameter.GetInstance(pbeParameters);
salt = pbeParams.GetSalt();
iterationCount = pbeParams.IterationCount.IntValue;
keyBytes = PbeParametersGenerator.Pkcs5PasswordToBytes(password);
}
ICipherParameters parameters = null;
if (IsPkcs5Scheme2(mechanism))
{
PbeS2Parameters s2p = PbeS2Parameters.GetInstance(pbeParameters.ToAsn1Object());
AlgorithmIdentifier encScheme = s2p.EncryptionScheme;
DerObjectIdentifier encOid = encScheme.ObjectID;
Asn1Object encParams = encScheme.Parameters.ToAsn1Object();
// TODO What about s2p.KeyDerivationFunc.ObjectID?
Pbkdf2Params pbeParams = Pbkdf2Params.GetInstance(s2p.KeyDerivationFunc.Parameters.ToAsn1Object());
byte[] iv;
if (encOid.Equals(PkcsObjectIdentifiers.RC2Cbc)) // PKCS5.B.2.3
{
RC2CbcParameter rc2Params = RC2CbcParameter.GetInstance(encParams);
iv = rc2Params.GetIV();
}
else
{
iv = Asn1OctetString.GetInstance(encParams).GetOctets();
}
salt = pbeParams.GetSalt();
iterationCount = pbeParams.IterationCount.IntValue;
keyBytes = PbeParametersGenerator.Pkcs5PasswordToBytes(password);
int keyLength = pbeParams.KeyLength != null
? pbeParams.KeyLength.IntValue * 8
: GeneratorUtilities.GetDefaultKeySize(encOid);
PbeParametersGenerator gen = MakePbeGenerator(
(string)algorithmType[mechanism], null, keyBytes, salt, iterationCount);
parameters = gen.GenerateDerivedParameters(encOid.Id, keyLength);
if (iv != null)
{
// FIXME? OpenSSL weirdness with IV of zeros (for ECB keys?)
if (Arrays.AreEqual(iv, new byte[iv.Length]))
{
//Console.Error.Write("***** IV all 0 (length " + iv.Length + ") *****");
}
else
{
parameters = new ParametersWithIV(parameters, iv);
}
}
}
else if (mechanism.StartsWith("PBEwithSHA-1"))
{
PbeParametersGenerator generator = MakePbeGenerator(
(string) algorithmType[mechanism], new Sha1Digest(), keyBytes, salt, iterationCount);
if (mechanism.Equals("PBEwithSHA-1and128bitAES-CBC-BC"))
{
parameters = generator.GenerateDerivedParameters("AES", 128, 128);
}
else if (mechanism.Equals("PBEwithSHA-1and192bitAES-CBC-BC"))
{
parameters = generator.GenerateDerivedParameters("AES", 192, 128);
}
else if (mechanism.Equals("PBEwithSHA-1and256bitAES-CBC-BC"))
{
parameters = generator.GenerateDerivedParameters("AES", 256, 128);
}
else if (mechanism.Equals("PBEwithSHA-1and128bitRC4"))
{
parameters = generator.GenerateDerivedParameters("RC4", 128);
}
else if (mechanism.Equals("PBEwithSHA-1and40bitRC4"))
{
parameters = generator.GenerateDerivedParameters("RC4", 40);
}
else if (mechanism.Equals("PBEwithSHA-1and3-keyDESEDE-CBC"))
{
parameters = generator.GenerateDerivedParameters("DESEDE", 192, 64);
}
else if (mechanism.Equals("PBEwithSHA-1and2-keyDESEDE-CBC"))
{
parameters = generator.GenerateDerivedParameters("DESEDE", 128, 64);
}
else if (mechanism.Equals("PBEwithSHA-1and128bitRC2-CBC"))
{
parameters = generator.GenerateDerivedParameters("RC2", 128, 64);
}
else if (mechanism.Equals("PBEwithSHA-1and40bitRC2-CBC"))
{
parameters = generator.GenerateDerivedParameters("RC2", 40, 64);
}
else if (mechanism.Equals("PBEwithSHA-1andDES-CBC"))
{
parameters = generator.GenerateDerivedParameters("DES", 64, 64);
}
else if (mechanism.Equals("PBEwithSHA-1andRC2-CBC"))
{
parameters = generator.GenerateDerivedParameters("RC2", 64, 64);
}
}
else if (mechanism.StartsWith("PBEwithSHA-256"))
{
PbeParametersGenerator generator = MakePbeGenerator(
(string) algorithmType[mechanism], new Sha256Digest(), keyBytes, salt, iterationCount);
if (mechanism.Equals("PBEwithSHA-256and128bitAES-CBC-BC"))
{
parameters = generator.GenerateDerivedParameters("AES", 128, 128);
}
else if (mechanism.Equals("PBEwithSHA-256and192bitAES-CBC-BC"))
{
parameters = generator.GenerateDerivedParameters("AES", 192, 128);
}
else if (mechanism.Equals("PBEwithSHA-256and256bitAES-CBC-BC"))
{
parameters = generator.GenerateDerivedParameters("AES", 256, 128);
}
}
else if (mechanism.StartsWith("PBEwithMD5"))
{
PbeParametersGenerator generator = MakePbeGenerator(
(string)algorithmType[mechanism], new MD5Digest(), keyBytes, salt, iterationCount);
if (mechanism.Equals("PBEwithMD5andDES-CBC"))
{
parameters = generator.GenerateDerivedParameters("DES", 64, 64);
}
else if (mechanism.Equals("PBEwithMD5andRC2-CBC"))
{
parameters = generator.GenerateDerivedParameters("RC2", 64, 64);
}
else if (mechanism.Equals("PBEwithMD5and128bitAES-CBC-OpenSSL"))
{
parameters = generator.GenerateDerivedParameters("AES", 128, 128);
}
else if (mechanism.Equals("PBEwithMD5and192bitAES-CBC-OpenSSL"))
{
parameters = generator.GenerateDerivedParameters("AES", 192, 128);
}
else if (mechanism.Equals("PBEwithMD5and256bitAES-CBC-OpenSSL"))
{
parameters = generator.GenerateDerivedParameters("AES", 256, 128);
}
}
else if (mechanism.StartsWith("PBEwithMD2"))
{
PbeParametersGenerator generator = MakePbeGenerator(
(string)algorithmType[mechanism], new MD2Digest(), keyBytes, salt, iterationCount);
if (mechanism.Equals("PBEwithMD2andDES-CBC"))
{
parameters = generator.GenerateDerivedParameters("DES", 64, 64);
}
else if (mechanism.Equals("PBEwithMD2andRC2-CBC"))
{
parameters = generator.GenerateDerivedParameters("RC2", 64, 64);
}
}
else if (mechanism.StartsWith("PBEwithHmac"))
{
string digestName = mechanism.Substring("PBEwithHmac".Length);
IDigest digest = DigestUtilities.GetDigest(digestName);
PbeParametersGenerator generator = MakePbeGenerator(
(string) algorithmType[mechanism], digest, keyBytes, salt, iterationCount);
int bitLen = digest.GetDigestSize() * 8;
parameters = generator.GenerateDerivedMacParameters(bitLen);
}
Array.Clear(keyBytes, 0, keyBytes.Length);
return FixDesParity(mechanism, parameters);
}
