public static byte[] GetObsoleteSharedSecret(AsymmetricCipherKeyPair localKeyWithPrivate, byte[] remotePublicKeyDerEncoded)
{
var remotePublicKey = PublicKeyFactory.CreateKey(remotePublicKeyDerEncoded);
var agreement = new ECDHBasicAgreement();
agreement.Init(localKeyWithPrivate.Private);
return agreement.CalculateAgreement(remotePublicKey).ToByteArray();
}
public static byte[] GetSharedSecret(AsymmetricCipherKeyPair localKeyWithPrivate, byte[] remotePublicKeyDerEncoded)
{
var remotePublicKey = PublicKeyFactory.CreateKey(remotePublicKeyDerEncoded);
var agreement = new ECDHBasicAgreement();
agreement.Init(localKeyWithPrivate.Private);
using (var sha = SHA256.Create()) {
// CalculateAgreement returns a BigInteger, whose length is variable, and bits are not whitened.
// So hash it.
return sha.ComputeHash(agreement.CalculateAgreement(remotePublicKey).ToByteArray());
}
}
public static IBufferedCipher GetCipher(
string algorithm)
{
if (algorithm == null)
throw new ArgumentNullException("algorithm");
algorithm = Platform.ToUpperInvariant(algorithm);
{
string aliased = (string) algorithms[algorithm];
if (aliased != null)
algorithm = aliased;
}
IBasicAgreement iesAgreement = null;
if (algorithm == "IES")
{
iesAgreement = new DHBasicAgreement();
}
else if (algorithm == "ECIES")
{
iesAgreement = new ECDHBasicAgreement();
}
if (iesAgreement != null)
{
return new BufferedIesCipher(
new IesEngine(
iesAgreement,
new Kdf2BytesGenerator(
new Sha1Digest()),
new HMac(
new Sha1Digest())));
}
if (algorithm.StartsWith("PBE"))
{
if (algorithm.EndsWith("-CBC"))
{
if (algorithm == "PBEWITHSHA1ANDDES-CBC")
{
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new DesEngine()));
}
else if (algorithm == "PBEWITHSHA1ANDRC2-CBC")
{
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new RC2Engine()));
}
else if (Strings.IsOneOf(algorithm,
"PBEWITHSHAAND2-KEYTRIPLEDES-CBC", "PBEWITHSHAAND3-KEYTRIPLEDES-CBC"))
{
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new DesEdeEngine()));
}
else if (Strings.IsOneOf(algorithm,
"PBEWITHSHAAND128BITRC2-CBC", "PBEWITHSHAAND40BITRC2-CBC"))
{
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new RC2Engine()));
}
}
else if (algorithm.EndsWith("-BC") || algorithm.EndsWith("-OPENSSL"))
{
if (Strings.IsOneOf(algorithm,
"PBEWITHSHAAND128BITAES-CBC-BC",
"PBEWITHSHAAND192BITAES-CBC-BC",
"PBEWITHSHAAND256BITAES-CBC-BC",
"PBEWITHSHA256AND128BITAES-CBC-BC",
"PBEWITHSHA256AND192BITAES-CBC-BC",
"PBEWITHSHA256AND256BITAES-CBC-BC",
"PBEWITHMD5AND128BITAES-CBC-OPENSSL",
"PBEWITHMD5AND192BITAES-CBC-OPENSSL",
"PBEWITHMD5AND256BITAES-CBC-OPENSSL"))
{
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new AesFastEngine()));
}
}
}
string[] parts = algorithm.Split('/');
IBlockCipher blockCipher = null;
IAsymmetricBlockCipher asymBlockCipher = null;
IStreamCipher streamCipher = null;
string algorithmName = parts[0];
{
string aliased = (string)algorithms[algorithmName];
if (aliased != null)
algorithmName = aliased;
}
CipherAlgorithm cipherAlgorithm;
try
{
cipherAlgorithm = (CipherAlgorithm)Enums.GetEnumValue(typeof(CipherAlgorithm), algorithmName);
}
catch (ArgumentException)
{
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
switch (cipherAlgorithm)
{
case CipherAlgorithm.AES:
blockCipher = new AesFastEngine();
break;
case CipherAlgorithm.ARC4:
streamCipher = new RC4Engine();
break;
case CipherAlgorithm.BLOWFISH:
blockCipher = new BlowfishEngine();
break;
case CipherAlgorithm.CAMELLIA:
blockCipher = new CamelliaEngine();
break;
case CipherAlgorithm.CAST5:
blockCipher = new Cast5Engine();
break;
case CipherAlgorithm.CAST6:
blockCipher = new Cast6Engine();
break;
case CipherAlgorithm.DES:
blockCipher = new DesEngine();
break;
case CipherAlgorithm.DESEDE:
blockCipher = new DesEdeEngine();
break;
case CipherAlgorithm.ELGAMAL:
asymBlockCipher = new ElGamalEngine();
break;
case CipherAlgorithm.GOST28147:
blockCipher = new Gost28147Engine();
break;
case CipherAlgorithm.HC128:
streamCipher = new HC128Engine();
break;
case CipherAlgorithm.HC256:
streamCipher = new HC256Engine();
break;
case CipherAlgorithm.IDEA:
blockCipher = new IdeaEngine();
break;
case CipherAlgorithm.NOEKEON:
blockCipher = new NoekeonEngine();
break;
case CipherAlgorithm.PBEWITHSHAAND128BITRC4:
case CipherAlgorithm.PBEWITHSHAAND40BITRC4:
streamCipher = new RC4Engine();
break;
case CipherAlgorithm.RC2:
blockCipher = new RC2Engine();
break;
case CipherAlgorithm.RC5:
blockCipher = new RC532Engine();
break;
case CipherAlgorithm.RC5_64:
blockCipher = new RC564Engine();
break;
case CipherAlgorithm.RC6:
blockCipher = new RC6Engine();
break;
case CipherAlgorithm.RIJNDAEL:
blockCipher = new RijndaelEngine();
break;
case CipherAlgorithm.RSA:
asymBlockCipher = new RsaBlindedEngine();
break;
case CipherAlgorithm.SALSA20:
streamCipher = new Salsa20Engine();
break;
case CipherAlgorithm.SEED:
blockCipher = new SeedEngine();
break;
case CipherAlgorithm.SERPENT:
blockCipher = new SerpentEngine();
break;
case CipherAlgorithm.SKIPJACK:
blockCipher = new SkipjackEngine();
break;
case CipherAlgorithm.TEA:
blockCipher = new TeaEngine();
break;
case CipherAlgorithm.TWOFISH:
blockCipher = new TwofishEngine();
break;
case CipherAlgorithm.VMPC:
streamCipher = new VmpcEngine();
break;
case CipherAlgorithm.VMPC_KSA3:
streamCipher = new VmpcKsa3Engine();
break;
case CipherAlgorithm.XTEA:
blockCipher = new XteaEngine();
break;
default:
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
if (streamCipher != null)
{
if (parts.Length > 1)
throw new ArgumentException("Modes and paddings not used for stream ciphers");
return new BufferedStreamCipher(streamCipher);
}
bool cts = false;
bool padded = true;
IBlockCipherPadding padding = null;
IAeadBlockCipher aeadBlockCipher = null;
if (parts.Length > 2)
{
if (streamCipher != null)
throw new ArgumentException("Paddings not used for stream ciphers");
string paddingName = parts[2];
CipherPadding cipherPadding;
if (paddingName == "")
{
cipherPadding = CipherPadding.RAW;
}
else if (paddingName == "X9.23PADDING")
{
cipherPadding = CipherPadding.X923PADDING;
}
else
{
try
{
cipherPadding = (CipherPadding)Enums.GetEnumValue(typeof(CipherPadding), paddingName);
}
catch (ArgumentException)
{
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
}
switch (cipherPadding)
{
case CipherPadding.NOPADDING:
padded = false;
break;
case CipherPadding.RAW:
break;
case CipherPadding.ISO10126PADDING:
case CipherPadding.ISO10126D2PADDING:
case CipherPadding.ISO10126_2PADDING:
padding = new ISO10126d2Padding();
break;
case CipherPadding.ISO7816_4PADDING:
case CipherPadding.ISO9797_1PADDING:
padding = new ISO7816d4Padding();
break;
case CipherPadding.ISO9796_1:
case CipherPadding.ISO9796_1PADDING:
asymBlockCipher = new ISO9796d1Encoding(asymBlockCipher);
break;
case CipherPadding.OAEP:
case CipherPadding.OAEPPADDING:
asymBlockCipher = new OaepEncoding(asymBlockCipher);
break;
case CipherPadding.OAEPWITHMD5ANDMGF1PADDING:
asymBlockCipher = new OaepEncoding(asymBlockCipher, new MD5Digest());
break;
case CipherPadding.OAEPWITHSHA1ANDMGF1PADDING:
case CipherPadding.OAEPWITHSHA_1ANDMGF1PADDING:
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha1Digest());
break;
case CipherPadding.OAEPWITHSHA224ANDMGF1PADDING:
case CipherPadding.OAEPWITHSHA_224ANDMGF1PADDING:
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha224Digest());
break;
case CipherPadding.OAEPWITHSHA256ANDMGF1PADDING:
case CipherPadding.OAEPWITHSHA_256ANDMGF1PADDING:
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha256Digest());
break;
case CipherPadding.OAEPWITHSHA384ANDMGF1PADDING:
case CipherPadding.OAEPWITHSHA_384ANDMGF1PADDING:
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha384Digest());
break;
case CipherPadding.OAEPWITHSHA512ANDMGF1PADDING:
case CipherPadding.OAEPWITHSHA_512ANDMGF1PADDING:
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha512Digest());
break;
case CipherPadding.PKCS1:
case CipherPadding.PKCS1PADDING:
asymBlockCipher = new Pkcs1Encoding(asymBlockCipher);
break;
case CipherPadding.PKCS5:
case CipherPadding.PKCS5PADDING:
case CipherPadding.PKCS7:
case CipherPadding.PKCS7PADDING:
padding = new Pkcs7Padding();
break;
case CipherPadding.TBCPADDING:
padding = new TbcPadding();
break;
case CipherPadding.WITHCTS:
cts = true;
break;
case CipherPadding.X923PADDING:
padding = new X923Padding();
break;
case CipherPadding.ZEROBYTEPADDING:
padding = new ZeroBytePadding();
break;
default:
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
}
string mode = "";
if (parts.Length > 1)
{
mode = parts[1];
int di = GetDigitIndex(mode);
string modeName = di >= 0 ? mode.Substring(0, di) : mode;
try
{
CipherMode cipherMode = modeName == ""
? CipherMode.NONE
: (CipherMode)Enums.GetEnumValue(typeof(CipherMode), modeName);
switch (cipherMode)
{
case CipherMode.ECB:
case CipherMode.NONE:
break;
case CipherMode.CBC:
blockCipher = new CbcBlockCipher(blockCipher);
break;
case CipherMode.CCM:
aeadBlockCipher = new CcmBlockCipher(blockCipher);
break;
case CipherMode.CFB:
{
int bits = (di < 0)
? 8 * blockCipher.GetBlockSize()
: int.Parse(mode.Substring(di));
blockCipher = new CfbBlockCipher(blockCipher, bits);
break;
}
case CipherMode.CTR:
blockCipher = new SicBlockCipher(blockCipher);
break;
case CipherMode.CTS:
cts = true;
blockCipher = new CbcBlockCipher(blockCipher);
break;
case CipherMode.EAX:
aeadBlockCipher = new EaxBlockCipher(blockCipher);
break;
case CipherMode.GCM:
aeadBlockCipher = new GcmBlockCipher(blockCipher);
break;
case CipherMode.GOFB:
blockCipher = new GOfbBlockCipher(blockCipher);
break;
case CipherMode.OCB:
aeadBlockCipher = new OcbBlockCipher(blockCipher, CreateBlockCipher(cipherAlgorithm));
break;
case CipherMode.OFB:
{
int bits = (di < 0)
? 8 * blockCipher.GetBlockSize()
: int.Parse(mode.Substring(di));
blockCipher = new OfbBlockCipher(blockCipher, bits);
break;
}
case CipherMode.OPENPGPCFB:
blockCipher = new OpenPgpCfbBlockCipher(blockCipher);
break;
case CipherMode.SIC:
if (blockCipher.GetBlockSize() < 16)
{
throw new ArgumentException("Warning: SIC-Mode can become a twotime-pad if the blocksize of the cipher is too small. Use a cipher with a block size of at least 128 bits (e.g. AES)");
}
blockCipher = new SicBlockCipher(blockCipher);
break;
default:
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
}
catch (ArgumentException)
{
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
}
if (aeadBlockCipher != null)
{
if (cts)
throw new SecurityUtilityException("CTS mode not valid for AEAD ciphers.");
if (padded && parts.Length > 2 && parts[2] != "")
throw new SecurityUtilityException("Bad padding specified for AEAD cipher.");
return new BufferedAeadBlockCipher(aeadBlockCipher);
}
if (blockCipher != null)
{
if (cts)
{
return new CtsBlockCipher(blockCipher);
}
if (padding != null)
{
return new PaddedBufferedBlockCipher(blockCipher, padding);
}
if (!padded || blockCipher.IsPartialBlockOkay)
{
return new BufferedBlockCipher(blockCipher);
}
return new PaddedBufferedBlockCipher(blockCipher);
}
if (asymBlockCipher != null)
{
return new BufferedAsymmetricBlockCipher(asymBlockCipher);
}
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
public static IBufferedCipher GetCipher(
string algorithm)
{
if (algorithm == null)
throw new ArgumentNullException("algorithm");
algorithm = algorithm.ToUpper(CultureInfo.InvariantCulture);
string aliased = (string) algorithms[algorithm];
if (aliased != null)
algorithm = aliased;
IBasicAgreement iesAgreement = null;
if (algorithm == "IES")
{
iesAgreement = new DHBasicAgreement();
}
else if (algorithm == "ECIES")
{
iesAgreement = new ECDHBasicAgreement();
}
if (iesAgreement != null)
{
return new BufferedIesCipher(
new IesEngine(
iesAgreement,
new Kdf2BytesGenerator(
new Sha1Digest()),
new HMac(
new Sha1Digest())));
}
if (algorithm.StartsWith("PBE"))
{
switch (algorithm)
{
case "PBEWITHSHAAND2-KEYTRIPLEDES-CBC":
case "PBEWITHSHAAND3-KEYTRIPLEDES-CBC":
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new DesEdeEngine()));
case "PBEWITHSHAAND128BITRC2-CBC":
case "PBEWITHSHAAND40BITRC2-CBC":
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new RC2Engine()));
case "PBEWITHSHAAND128BITAES-CBC-BC":
case "PBEWITHSHAAND192BITAES-CBC-BC":
case "PBEWITHSHAAND256BITAES-CBC-BC":
case "PBEWITHSHA256AND128BITAES-CBC-BC":
case "PBEWITHSHA256AND192BITAES-CBC-BC":
case "PBEWITHSHA256AND256BITAES-CBC-BC":
case "PBEWITHMD5AND128BITAES-CBC-OPENSSL":
case "PBEWITHMD5AND192BITAES-CBC-OPENSSL":
case "PBEWITHMD5AND256BITAES-CBC-OPENSSL":
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new AesFastEngine()));
case "PBEWITHSHA1ANDDES-CBC":
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new DesEngine()));
case "PBEWITHSHA1ANDRC2-CBC":
return new PaddedBufferedBlockCipher(
new CbcBlockCipher(new RC2Engine()));
}
}
string[] parts = algorithm.Split('/');
IBlockCipher blockCipher = null;
IAsymmetricBlockCipher asymBlockCipher = null;
IStreamCipher streamCipher = null;
switch (parts[0])
{
case "AES":
blockCipher = new AesFastEngine();
break;
case "ARC4":
streamCipher = new RC4Engine();
break;
case "BLOWFISH":
blockCipher = new BlowfishEngine();
break;
case "CAMELLIA":
blockCipher = new CamelliaEngine();
break;
case "CAST5":
blockCipher = new Cast5Engine();
break;
case "CAST6":
blockCipher = new Cast6Engine();
break;
case "DES":
blockCipher = new DesEngine();
break;
case "DESEDE":
blockCipher = new DesEdeEngine();
break;
case "ELGAMAL":
asymBlockCipher = new ElGamalEngine();
break;
case "GOST28147":
blockCipher = new Gost28147Engine();
break;
case "HC128":
streamCipher = new HC128Engine();
break;
case "HC256":
streamCipher = new HC256Engine();
break;
#if INCLUDE_IDEA
case "IDEA":
blockCipher = new IdeaEngine();
break;
#endif
case "NOEKEON":
blockCipher = new NoekeonEngine();
break;
case "PBEWITHSHAAND128BITRC4":
case "PBEWITHSHAAND40BITRC4":
streamCipher = new RC4Engine();
break;
case "RC2":
blockCipher = new RC2Engine();
break;
case "RC5":
blockCipher = new RC532Engine();
break;
case "RC5-64":
blockCipher = new RC564Engine();
break;
case "RC6":
blockCipher = new RC6Engine();
break;
case "RIJNDAEL":
blockCipher = new RijndaelEngine();
break;
case "RSA":
asymBlockCipher = new RsaBlindedEngine();
break;
case "SALSA20":
streamCipher = new Salsa20Engine();
break;
case "SEED":
blockCipher = new SeedEngine();
break;
case "SERPENT":
blockCipher = new SerpentEngine();
break;
case "SKIPJACK":
blockCipher = new SkipjackEngine();
break;
case "TEA":
blockCipher = new TeaEngine();
break;
case "TWOFISH":
blockCipher = new TwofishEngine();
break;
case "VMPC":
streamCipher = new VmpcEngine();
break;
case "VMPC-KSA3":
streamCipher = new VmpcKsa3Engine();
break;
case "XTEA":
blockCipher = new XteaEngine();
break;
default:
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
if (streamCipher != null)
{
if (parts.Length > 1)
throw new ArgumentException("Modes and paddings not used for stream ciphers");
return new BufferedStreamCipher(streamCipher);
}
bool cts = false;
bool padded = true;
IBlockCipherPadding padding = null;
IAeadBlockCipher aeadBlockCipher = null;
if (parts.Length > 2)
{
if (streamCipher != null)
throw new ArgumentException("Paddings not used for stream ciphers");
switch (parts[2])
{
case "NOPADDING":
padded = false;
break;
case "":
case "RAW":
break;
case "ISO10126PADDING":
case "ISO10126D2PADDING":
case "ISO10126-2PADDING":
padding = new ISO10126d2Padding();
break;
case "ISO7816-4PADDING":
case "ISO9797-1PADDING":
padding = new ISO7816d4Padding();
break;
case "ISO9796-1":
case "ISO9796-1PADDING":
asymBlockCipher = new ISO9796d1Encoding(asymBlockCipher);
break;
case "OAEP":
case "OAEPPADDING":
asymBlockCipher = new OaepEncoding(asymBlockCipher);
break;
case "OAEPWITHMD5ANDMGF1PADDING":
asymBlockCipher = new OaepEncoding(asymBlockCipher, new MD5Digest());
break;
case "OAEPWITHSHA1ANDMGF1PADDING":
case "OAEPWITHSHA-1ANDMGF1PADDING":
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha1Digest());
break;
case "OAEPWITHSHA224ANDMGF1PADDING":
case "OAEPWITHSHA-224ANDMGF1PADDING":
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha224Digest());
break;
case "OAEPWITHSHA256ANDMGF1PADDING":
case "OAEPWITHSHA-256ANDMGF1PADDING":
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha256Digest());
break;
case "OAEPWITHSHA384ANDMGF1PADDING":
case "OAEPWITHSHA-384ANDMGF1PADDING":
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha384Digest());
break;
case "OAEPWITHSHA512ANDMGF1PADDING":
case "OAEPWITHSHA-512ANDMGF1PADDING":
asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha512Digest());
break;
case "PKCS1":
case "PKCS1PADDING":
asymBlockCipher = new Pkcs1Encoding(asymBlockCipher);
break;
case "PKCS5":
case "PKCS5PADDING":
case "PKCS7":
case "PKCS7PADDING":
padding = new Pkcs7Padding();
break;
case "TBCPADDING":
padding = new TbcPadding();
break;
case "WITHCTS":
cts = true;
break;
case "X9.23PADDING":
case "X923PADDING":
padding = new X923Padding();
break;
case "ZEROBYTEPADDING":
padding = new ZeroBytePadding();
break;
default:
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
}
string mode = "";
if (parts.Length > 1)
{
mode = parts[1];
int di = GetDigitIndex(mode);
string modeName = di >= 0 ? mode.Substring(0, di) : mode;
switch (modeName)
{
case "":
case "ECB":
case "NONE":
break;
case "CBC":
blockCipher = new CbcBlockCipher(blockCipher);
break;
case "CCM":
aeadBlockCipher = new CcmBlockCipher(blockCipher);
break;
case "CFB":
{
int bits = (di < 0)
? 8 * blockCipher.GetBlockSize()
: int.Parse(mode.Substring(di));
blockCipher = new CfbBlockCipher(blockCipher, bits);
break;
}
case "CTR":
blockCipher = new SicBlockCipher(blockCipher);
break;
case "CTS":
cts = true;
blockCipher = new CbcBlockCipher(blockCipher);
break;
case "EAX":
aeadBlockCipher = new EaxBlockCipher(blockCipher);
break;
case "GCM":
aeadBlockCipher = new GcmBlockCipher(blockCipher);
break;
case "GOFB":
blockCipher = new GOfbBlockCipher(blockCipher);
break;
case "OFB":
{
int bits = (di < 0)
? 8 * blockCipher.GetBlockSize()
: int.Parse(mode.Substring(di));
blockCipher = new OfbBlockCipher(blockCipher, bits);
break;
}
case "OPENPGPCFB":
blockCipher = new OpenPgpCfbBlockCipher(blockCipher);
break;
case "SIC":
if (blockCipher.GetBlockSize() < 16)
{
throw new ArgumentException("Warning: SIC-Mode can become a twotime-pad if the blocksize of the cipher is too small. Use a cipher with a block size of at least 128 bits (e.g. AES)");
}
blockCipher = new SicBlockCipher(blockCipher);
break;
default:
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
}
if (aeadBlockCipher != null)
{
if (cts)
throw new SecurityUtilityException("CTS mode not valid for AEAD ciphers.");
if (padded && parts.Length > 2 && parts[2] != "")
throw new SecurityUtilityException("Bad padding specified for AEAD cipher.");
return new BufferedAeadBlockCipher(aeadBlockCipher);
}
if (blockCipher != null)
{
if (cts)
{
return new CtsBlockCipher(blockCipher);
}
if (padding != null)
{
return new PaddedBufferedBlockCipher(blockCipher, padding);
}
if (!padded || blockCipher.IsPartialBlockOkay)
{
return new BufferedBlockCipher(blockCipher);
}
return new PaddedBufferedBlockCipher(blockCipher);
}
if (asymBlockCipher != null)
{
return new BufferedAsymmetricBlockCipher(asymBlockCipher);
}
throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
}
public static EncryptionResult EncryptMessage(byte[] userKey, byte[] userSecret, byte[] data, ushort padding = 0, bool randomisePadding = false)
{
var Random = new SecureRandom();
var Salt = new byte[16];
Random.NextBytes(Salt);
var Curve = ECNamedCurveTable.GetByName("prime256v1");
var Spec = new ECDomainParameters(Curve.Curve, Curve.G, Curve.N, Curve.H, Curve.GetSeed());
var Generator = new ECKeyPairGenerator();
Generator.Init(new ECKeyGenerationParameters(Spec, new SecureRandom()));
var KeyPair = Generator.GenerateKeyPair();
var AgreementGenerator = new ECDHBasicAgreement();
AgreementGenerator.Init(KeyPair.Private);
var IKM =
AgreementGenerator.CalculateAgreement(new ECPublicKeyParameters(Spec.Curve.DecodePoint(userKey), Spec));
var PRK = GenerateHKDF(userSecret, IKM.ToByteArrayUnsigned(),
Encoding.UTF8.GetBytes("Content-Encoding: auth\0"), 32);
var PublicKey = ((ECPublicKeyParameters)KeyPair.Public).Q.GetEncoded(false);
var CEK = GenerateHKDF(Salt, PRK, CreateInfoChunk("aesgcm", userKey, PublicKey), 16);
var Nonce = GenerateHKDF(Salt, PRK, CreateInfoChunk("nonce", userKey, PublicKey), 12);
if (randomisePadding && (padding > 0)) padding = Convert.ToUInt16(Math.Abs(Random.NextInt()) % (padding + 1));
var Input = new byte[padding + 2 + data.Length];
Buffer.BlockCopy(ConvertInt(padding), 0, Input, 0, 2);
Buffer.BlockCopy(data, 0, Input, padding + 2, data.Length);
var Cipher = CipherUtilities.GetCipher("AES/GCM/NoPadding");
Cipher.Init(true, new AeadParameters(new KeyParameter(CEK), 128, Nonce));
var Message = new byte[Cipher.GetOutputSize(Input.Length)];
Cipher.DoFinal(Input, 0, Input.Length, Message, 0);
return new EncryptionResult { Salt = Salt, Payload = Message, PublicKey = PublicKey };
}
public void TestECBasicAgreementTest()
{
SecureRandom random = new SecureRandom();
FpCurve curve = new FpCurve(
new BigInteger("883423532389192164791648750360308885314476597252960362792450860609699839"), // q
new BigInteger("7fffffffffffffffffffffff7fffffffffff8000000000007ffffffffffc", 16), // a
new BigInteger("6b016c3bdcf18941d0d654921475ca71a9db2fb27d1d37796185c2942c0a", 16)); // b
ECDomainParameters parameters = new ECDomainParameters(
curve,
curve.DecodePoint(Hex.Decode("020ffa963cdca8816ccc33b8642bedf905c3d358573d3f27fbbd3b3cb9aaaf")), // G
new BigInteger("883423532389192164791648750360308884807550341691627752275345424702807307")); // n
ECKeyPairGenerator pGen = new ECKeyPairGenerator();
ECKeyGenerationParameters genParam = new ECKeyGenerationParameters(parameters, random);
pGen.Init(genParam);
AsymmetricCipherKeyPair p1 = pGen.GenerateKeyPair();
AsymmetricCipherKeyPair p2 = pGen.GenerateKeyPair();
//
// two way
//
IBasicAgreement e1 = new ECDHBasicAgreement();
IBasicAgreement e2 = new ECDHBasicAgreement();
e1.Init(p1.Private);
e2.Init(p2.Private);
BigInteger k1 = e1.CalculateAgreement(p2.Public);
BigInteger k2 = e2.CalculateAgreement(p1.Public);
if (!k1.Equals(k2))
{
Fail("calculated agreement test failed");
}
//
// two way
//
e1 = new ECDHCBasicAgreement();
e2 = new ECDHCBasicAgreement();
e1.Init(p1.Private);
e2.Init(p2.Private);
k1 = e1.CalculateAgreement(p2.Public);
k2 = e2.CalculateAgreement(p1.Public);
if (!k1.Equals(k2))
{
Fail("calculated agreement test failed");
}
}
BigInteger ECDHAgree(byte[] publicKey, byte[] privateKey)
{
var domain = SecNamedCurves.GetByName ("secp160r1");
ECDHBasicAgreement agreement = new ECDHBasicAgreement ();
BigInteger privKeyInt = new BigInteger (privateKey);
ECDomainParameters parm = new ECDomainParameters(domain.Curve, domain.G, domain.N);
ECPrivateKeyParameters privKey = new ECPrivateKeyParameters (privKeyInt, parm);
agreement.Init (privKey);
var pt = Key.Curve.Curve.DecodePoint (publicKey);
ECPublicKeyParameters pubParams = new ECPublicKeyParameters (pt, parm);
return agreement.CalculateAgreement (pubParams);
}
protected virtual byte[] CalculateECDHBasicAgreement(ECPublicKeyParameters publicKey,
ECPrivateKeyParameters privateKey)
{
ECDHBasicAgreement basicAgreement = new ECDHBasicAgreement();
basicAgreement.Init(privateKey);
BigInteger agreement = basicAgreement.CalculateAgreement(publicKey);
return BigIntegers.AsUnsignedByteArray(agreement);
}
protected virtual byte[] CalculateECDHBasicAgreement(ECPublicKeyParameters publicKey,
ECPrivateKeyParameters privateKey)
{
ECDHBasicAgreement basicAgreement = new ECDHBasicAgreement();
basicAgreement.Init(privateKey);
BigInteger agreementValue = basicAgreement.CalculateAgreement(publicKey);
/*
* RFC 4492 5.10. Note that this octet string (Z in IEEE 1363 terminology) as output by
* FE2OSP, the Field Element to Octet String Conversion Primitive, has constant length for
* any given field; leading zeros found in this octet string MUST NOT be truncated.
*/
return BigIntegers.AsUnsignedByteArray(basicAgreement.GetFieldSize(), agreementValue);
}
/// <summary>
/// Generates the KDF parameters.
/// Sess Sections 7 & 8 of RFC 6637 (http://tools.ietf.org/html/rfc6637) for more details
/// </summary>
/// <returns></returns>
private void UpdateDigestWithKDFParameters(IDigest digest)
{
var agreement = new ECDHBasicAgreement();
agreement.Init(_privateKey);
var zb = agreement.CalculateAgreement(_publicKey).ToByteArrayUnsigned();
digest.Update(0x00);
digest.Update(0x00);
digest.Update(0x00);
digest.Update(0x01);
digest.BlockUpdate(zb, 0, zb.Length);
var oid = _publicKey.PublicKeyParamSet.ToBytes();
digest.Update((byte)oid.Length);
digest.BlockUpdate(oid, 0, oid.Length);
digest.Update((byte)PublicKeyAlgorithmTag.Ecdh);
digest.Update(0x3);
digest.Update(0x1);
digest.Update((byte)_publicKey.HashAlgorithm);
digest.Update((byte)_publicKey.SymmetricKeyAlgorithm);
digest.BlockUpdate(_anonymousSender, 0, _anonymousSender.Length);
digest.BlockUpdate(_fingerPrint, 0, _fingerPrint.Length);
}
public override void ProcessClientKeys(ProtocolVersion version, ProtocolVersion clientVersion, CertificatePrivateKey privateKey, byte[] data)
{
if (data == null)
{
throw new ArgumentNullException("data");
}
if (data.Length < 1)
{
throw new ArgumentException("data");
}
byte[] ecPointData = new byte[data[0]];
Buffer.BlockCopy(data, 1, ecPointData, 0, ecPointData.Length);
ECPoint ecPoint = domainParameters.Curve.DecodePoint(ecPointData);
var theirPublicKey = new ECPublicKeyParameters(ecPoint, domainParameters);
// Calculate the actual agreement
var agreement = new ECDHBasicAgreement();
agreement.Init(this.privateKey);
preMasterSecret = BigIntegerToByteArray(agreement.CalculateAgreement(theirPublicKey), 32);
this.logger?.Debug("Pre-Master secret: " + BitConverter.ToString(preMasterSecret));
}
/// <summary>
/// Called by client to get his ephemaral ECC keys
/// TODO: get information about which ECC curve should be used
/// </summary>
/// <param name="version"></param>
/// <param name="data"></param>
/// <returns></returns>
public override byte[] ProcessServerKeys(ProtocolVersion version, byte[] data, X509Certificate serverCertificate)
{
if (data == null)
{
throw new ArgumentNullException(nameof(data));
}
if (data.Length < 4) throw new ArgumentException(nameof(data));
//if (data[0] != 3 || data[1] != 0 || data[2] != 23)
if (data[0] != 3 || data[1] != 0)
{
throw new ArgumentException(nameof(data));
}
//if (data[3] != 65 || data[4] > data.Length - 4)
if (data[4] > data.Length - 4)
{
throw new ArgumentException(nameof(data));
}
// Extract the public key from the data
byte[] ecPointData = new byte[data[3]];
Buffer.BlockCopy(data, 4, ecPointData, 0, ecPointData.Length);
var ecPoint = this.ObtainCurveNameAndPoint(ecPointData, serverCertificate);
var theirPublicKey = new ECPublicKeyParameters(ecPoint, this.domainParameters);
// Calculate the actual agreement
var agreement = new ECDHBasicAgreement();
agreement.Init(this.privateKey);
this.preMasterSecret = BigIntegerToByteArray(agreement.CalculateAgreement(theirPublicKey), 32);
var signature = new byte[data.Length - 4 - data[3]];
Buffer.BlockCopy(data, 4 + data[3], signature, 0, signature.Length);
return signature;
}
