/// <summary>
/// Validate a password by checking the checksum.
/// </summary>
/// <param name="password">Password to validate.</param>
/// <returns><c>true</c> if the password is valid, <c>false</c> otherwise.</returns>
public static bool ValidatePassword(string password)
{
if (string.IsNullOrEmpty(password))
{
throw new ArgumentNullException(nameof(password));
}
// Sanitaze and check password
password = password.Replace(" ", "");
password = password.Replace(Environment.NewLine, "");
password = password.ToUpper();
if (password.Length != PasswordLength)
{
throw new ArgumentException("Invalid password length");
}
// Do decryption rounds
byte[] binary;
try {
password = Permutation.Decrypt(password, false);
binary = Substitution.Decrypt(password);
Scramble.Decrypt(binary[0], binary, 4, binary.Length - 5);
} catch {
return(false);
}
// Validate checksum
uint crc32 = BitConverter.ToUInt32(binary, 0);
uint newCrc32 = Crc32.Calculate(binary, 4, binary.Length - 5);
return(crc32 == newCrc32);
}
/// <summary>
/// Converts a password into mail information.
/// </summary>
/// <param name="password">The password to convert.</param>
/// <returns>Mail information from the password.</returns>
public static WonderSMail Convert(string password)
{
if (string.IsNullOrEmpty(password))
{
throw new ArgumentNullException(nameof(password));
}
// Sanitaze and check password
password = password.Replace(" ", "");
password = password.Replace("\t", "");
password = password.Replace(Environment.NewLine, "");
password = password.ToUpper();
if (password.Length != PasswordLength)
{
throw new ArgumentException("Invalid password length");
}
// Do decryption rounds
// The last byte for "scramble" is ignored. It should be the null
// terminator 0x00.
password = Permutation.Decrypt(password, false);
byte[] binary = Substitution.Decrypt(password);
Scramble.Decrypt(binary[0], binary, 4, binary.Length - 5);
// Validate checksum
uint crc32 = BitConverter.ToUInt32(binary, 0);
uint newCrc32 = Crc32.Calculate(binary, 4, binary.Length - 5);
if (crc32 != newCrc32)
{
throw new FormatException("Invalid crc32");
}
// Convert the binary password into the structure.
// Write the array into a stream to use the BitReader.
DataStream stream = new DataStream();
stream.Write(binary, 4, binary.Length - 4);
BitReader reader = new BitReader(stream);
WonderSMail info = new WonderSMail();
info.MailType = reader.ReadByte(4);
info.MissionType = reader.ReadByte(4);
info.MissionSubType = reader.ReadByte(4);
info.SourceClientId = reader.ReadUInt16(11);
info.TargetClientId = reader.ReadUInt16(11);
info.TargetClientFemale = reader.ReadUInt16(11);
info.RewardObjectId = reader.ReadUInt16(10);
info.RewardType = reader.ReadByte(4);
info.RewardId = reader.ReadUInt16(11);
info.RestrictionType = reader.ReadByte(1);
info.RestrictionParam = reader.ReadUInt16(11);
info.Random = reader.ReadUInt32(24);
info.LocationId = reader.ReadByte(8);
info.FloorNumber = reader.ReadByte(8);
info.Requirement = reader.ReadByte(8);
return(info);
}
/// <summary>
/// Validate a password by checking the checksum.
/// </summary>
/// <param name="password">Password to validate.</param>
/// <returns><c>true</c> if the password is valid, <c>false</c> otherwise.</returns>
public static bool ValidatePassword(string password)
{
if (string.IsNullOrEmpty(password))
{
throw new ArgumentNullException(nameof(password));
}
// Sanitaze and check password
password = password.Replace(" ", "");
password = password.Replace(Environment.NewLine, "");
password = password.ToUpper();
if (password.Length != PasswordLength)
{
throw new ArgumentException("Invalid password length");
}
// Do decryption rounds
byte[] binary;
try {
password = Permutation.Decrypt(password, true);
binary = Substitution.Decrypt(password);
Scramble.Decrypt(binary[0], binary, 1, binary.Length - 2);
} catch {
return(false);
}
// Validate checksum
byte checksum = binary[0];
byte newChecksum = Checksum.Calculate(binary, 1, binary.Length - 1);
return(checksum == newChecksum);
}
public void EncryptDecryptBasic()
{
Substitution sub = new Substitution(new Alphabet("PHQGIUMEAYLNOFDXJKRCVSTZWB"));
var encrypted = sub.Encrypt(TextExample);
Assert.AreEqual("GIUIFGCEIIPRCTPNN", encrypted);
var decrypted = sub.Decrypt(encrypted);
Assert.AreEqual(TextExample, decrypted);
}
/// <summary>
/// Converts a password into mail information.
/// </summary>
/// <param name="password">The password to convert.</param>
/// <returns>Mail information from the password.</returns>
public static MissionMail Convert(string password)
{
if (string.IsNullOrEmpty(password))
{
throw new ArgumentNullException(nameof(password));
}
// Sanitaze and check password
password = password.Replace(" ", "");
password = password.Replace(Environment.NewLine, "");
password = password.ToUpper();
if (password.Length != PasswordLength)
{
throw new ArgumentException("Invalid password length");
}
// Do decryption rounds
// The last byte for "scramble" is ignored. It should be the null
// terminator 0x00.
password = Permutation.Decrypt(password, true);
byte[] binary = Substitution.Decrypt(password);
Scramble.Decrypt(binary[0], binary, 1, binary.Length - 2);
// Validate checksum
byte checksum = binary[0]; // The scramble key is the checksum too.
byte newChecksum = Checksum.Calculate(binary, 1, binary.Length - 1);
if (checksum != newChecksum)
{
throw new FormatException("Invalid checksum");
}
// Convert the binary password into the structure.
// Write the array into a stream to use the BitReader.
DataStream stream = new DataStream();
stream.Write(binary, 1, binary.Length - 1);
BitReader reader = new BitReader(stream);
MissionMail info = new MissionMail();
info.Type = (MissionState)reader.ReadByte(4);
info.LocationId = reader.ReadByte(7);
info.FloorNumber = reader.ReadByte(7);
info.Random = (info.Type == MissionState.Sos) ? reader.ReadUInt32(24) : 0x00;
info.UID = reader.ReadUInt64(64);
info.ClientLanguage = (GameLanguage)reader.ReadByte(4);
info.ClientName = reader.ReadString(80, EncodingName);
info.ObjectID1 = (info.Type == MissionState.Sos) ? (ushort)0x00 : reader.ReadUInt16(10);
info.ObjectID2 = (info.Type == MissionState.Sos) ? (ushort)0x00 : reader.ReadUInt16(10);
info.RescuerUID = reader.ReadUInt64(64);
info.GameType = (GameType)reader.ReadByte(2);
return(info);
}
public IActionResult DecryptMessage([FromBody] VigenereModel message)
{
var encryptedText = message.Message;
var alphabet = message.Alphabet;
var password = message.Password;
Substitution cipher = new Substitution(alphabet);
message.Message = cipher.Decrypt(encryptedText, password);
return(Json(message));
}
public void Multigraph_SubstitutionTest()
{
Substitution substitution = new Substitution(Utility.KeyedEnglishAlphabet("KRYPTOS").ToStringArray());
for (int i = 0; i < 25; i++)
{
substitution.Key = substitution.ScrambledAlphabet();
generated = substitution.GenerateRandomLetters();
cipher = substitution.Encrypt(generated);
clear = substitution.Decrypt(cipher);
CollectionAssert.AreEqual(generated, clear);
}
}
public void Unigraph_SubstitutionTest()
{
Substitution substitution = new Substitution(Utility.KeyedEnglishAlphabet("KRYPTOS"));
cipher = "";
clear = "";
generated = "";
for (int i = 0; i < 25; i++)
{
substitution.Key = substitution.ScrambledAlphabet();
generated = substitution.GenerateRandomString();
cipher = substitution.Encrypt(generated);
clear = substitution.Decrypt(cipher);
Assert.AreEqual(generated, clear);
}
}
public static void RunThirdTask()
{
var basePath = $"{Directory.GetParent(Directory.GetCurrentDirectory()).Parent.Parent}\\Task3\\Data";
string allText = File.ReadAllText($"{basePath}\\bigrams_percentages.json");
var bigrams = JsonConvert.DeserializeObject <Dictionary <string, float> >(allText)
.Select(t => new EtalonMember(t.Key, t.Value)).ToList();
allText = File.ReadAllText($"{basePath}\\trigrams_percentages.json");
var trigrams = JsonConvert.DeserializeObject <Dictionary <string, float> >(allText)
.Select(t => new EtalonMember(t.Key, t.Value)).ToList();
string thirdTaskEncryptedMessage = "EFFPQLEKVTVPCPYFLMVHQLUEWCNVWFYGHYTCETHQEKLPVMSAKSPVPAPVYWMVHQLUSPQLYWLASLFVWPQLMVHQLUPLRPSQLULQESPBLWPCSVRVWFLHLWFLWPUEWFYOTCMQYSLWOYWYETHQEKLPVMSAKSPVPAPVYWHEPPLUWSGYULEMQTLPPLUGUYOLWDTVSQETHQEKLPVPVSMTLEUPQEPCYAMEWWYTYWDLUULTCYWPQLSEOLSVOHTLUYAPVWLYGDALSSVWDPQLNLCKCLRQEASPVILSLEUMQBQVMQCYAHUYKEKTCASLFPYFLMVHQLUPQLHULIVYASHEUEDUEHQBVTTPQLVWFLRYGMYVWMVFLWMLSPVTTBYUNESESADDLSPVYWCYAMEWPUCPYFVIVFLPQLOLSSEDLVWHEUPSKCPQLWAOKLUYGMQEUEMPLUSVWENLCEWFEHHTCGULXALWMCEWETCSVSPYLEMQYGPQLOMEWCYAGVWFEBECPYASLQVDQLUYUFLUGULXALWMCSPEPVSPVMSBVPQPQVSPCHLYGMVHQLUPQLWLRPOEDVMETBYUFBVTTPENLPYPQLWLRPTEKLWZYCKVPTCSTESQPQULLGYAUMEHVPETFWMEHVPETBZMEHVPETB";
string alphabet = new string(SingleByteXorAttacker.OneLetterEnglishFrequency.Select(c => c.Key).ToArray());
string thirdTaskKey = "EKMFLGDQVZNTOWYHXUSPAIBRCJ".ToLower();
var substitution = new Substitution(alphabet, new List <string> {
thirdTaskKey
});
Console.WriteLine(substitution.Decrypt(thirdTaskEncryptedMessage.ToLower()));
//var substitutionAttacker = new SubstitutionAttacker(
// encryptedText: thirdTaskEncryptedMessage,
// individualSetMembersCount: 1,
// minPopulationSize: 40,
// maxPopulationSize: 100,
// iterationsCount: 1000,
// mutationPercentage: 0.02F,
// bestPercentage: 30,
// twoLettersFrequencies: bigrams,
// threeLettersFrequencies: trigrams,
// twoLettersFittingQuotientCoef: 0.5F,
// threeLettersFittingQuotientCoef: 1.5F);
//List<IndividualSet> keySets = substitutionAttacker.Evaluate().Result;
//for(int i = 0; i < 10; i++)
//{
// Console.WriteLine($"Key set {i}:");
// keySets[i].ForEach(Console.WriteLine);
// Console.WriteLine();
//}
}