ZidUtilities.CommonCode 1.0.3

CommonCode

Core utility library providing common functionality used across the ZidUtilities solution.

Features

Security & Cryptography

• Crypter: Encryption and decryption utilities supporting multiple algorithms
• PasswordGenerator: Secure password generation with customizable complexity rules
• Check: Input validation and security checks

Data Management

• Extensions: Extension methods for common .NET types
• GenericTokenList & TokenList: Token-based list management
• SimpleDictionaryPersister: Dictionary persistence utilities
• XmlSerialization: XML serialization helpers

Data Comparison

• DifferenceEngine: Advanced data comparison utilities for detecting changes between datasets
• DataComparison: Data comparison and difference detection tools

Image Processing

• ImageHelper: Image manipulation and conversion utilities

Server Utilities

• ServerFiltering: Server-side filtering and data processing

Localization

• LanguageConfig: Language configuration and localization support

Dependencies

This is a core library with minimal external dependencies, designed to be lightweight and reusable.

Target Framework

.NET Framework 4.8

Usage Examples

Crypter - String Encryption and Decryption

Basic Encryption with Default Settings (AES-256)

using ZidUtilities.CommonCode;

var crypter = new Crypter();

// Encrypt a string
string plainText = "Sensitive data that needs protection";
string encryptionKey = "MySecurePassword123";
string encrypted = crypter.Encrypt(plainText, encryptionKey);

Console.WriteLine($"Encrypted: {encrypted}");

// Decrypt the string
string decrypted = crypter.Decrypt(encrypted, encryptionKey);
Console.WriteLine($"Decrypted: {decrypted}");

Using Different Encryption Algorithms

var crypter = new Crypter();

// Using AES (default and recommended)
string aesEncrypted = crypter.Encrypt("Secret data", "key", Crypter.Algorithm.AES);

// Using Rijndael
string rijndaelEncrypted = crypter.Encrypt("Secret data", "key", Crypter.Algorithm.Rijndael);

// For legacy compatibility (not recommended for new applications)
string tripleDesEncrypted = crypter.Encrypt("Secret data", "key", Crypter.Algorithm.Triple_Des);

Custom Configuration for Enhanced Security

var crypter = new Crypter
{
    SaltValue = "MyCustomSalt",
    PasswordIterations = 100000, // NIST recommended
    HashAlgorithm = "SHA256",
    KeySize = 256,
    UseModernKdf = true
};

string encrypted = crypter.Encrypt("High security data", "StrongPassword!");
string decrypted = crypter.Decrypt(encrypted, "StrongPassword!");

Legacy Data Compatibility

// If you need to decrypt data encrypted with old settings
var crypter = new Crypter();
crypter.SetLegacyValues(); // Uses SHA1, 2 iterations, 128-bit keys

string legacyDecrypted = crypter.Decrypt(oldEncryptedData, "OldPassword");

Crypter - File Encryption

Encrypting and Decrypting Files

var crypter = new Crypter();

// Encrypt a file
int result = crypter.EncryptFile(
    inputFile: @"C:\docs\confidential.pdf",
    outputFile: @"C:\docs\confidential.pdf.encrypted",
    encryptionKey: "FileProtectionKey2024"
);

if (result == 1)
{
    Console.WriteLine("File encrypted successfully!");

    // Decrypt the file
    result = crypter.DecryptFile(
        inputFile: @"C:\docs\confidential.pdf.encrypted",
        outputFile: @"C:\docs\confidential_decrypted.pdf",
        encryptionKey: "FileProtectionKey2024"
    );

    if (result == 1)
        Console.WriteLine("File decrypted successfully!");
}

Crypter - Hash Functions

Computing and Verifying Hashes

// MD5 Hash (use only for legacy compatibility)
string md5Hash = Crypter.GetMd5Sum("Hello World");
bool md5Valid = Crypter.VerifyMd5Sum("Hello World", md5Hash);

// SHA256 Hash (recommended for modern applications)
string sha256Hash = Crypter.GetSha256Sum("Hello World");
bool sha256Valid = Crypter.VerifySha256Sum("Hello World", sha256Hash);

// SHA512 Hash (maximum security)
string sha512Hash = Crypter.GetSha512Sum("Hello World");
bool sha512Valid = Crypter.VerifySha512Sum("Hello World", sha512Hash);

// File hashing
string fileHash = Crypter.GetSha256Sum(@"C:\docs\document.pdf");
Console.WriteLine($"File SHA256: {fileHash}");

PasswordGenerator - Creating Secure Passwords

Basic Password Generation

using ZidUtilities.CommonCode;

var generator = new PasswordGenerator(length: 12);

// Add rules for password composition
generator.Rules.Add(new PasswordComponent
{
    CompType = PasswordComponentType.UpperCase,
    Quantity = 2
});

generator.Rules.Add(new PasswordComponent
{
    CompType = PasswordComponentType.LowerCase,
    Quantity = 6
});

generator.Rules.Add(new PasswordComponent
{
    CompType = PasswordComponentType.Digit,
    Quantity = 2
});

generator.Rules.Add(new PasswordComponent
{
    CompType = PasswordComponentType.SpecialChar,
    Quantity = 2
});

string password = generator.GetPassword();
Console.WriteLine($"Generated Password: {password}");
// Example output: "aB3dEf!2gH@i"

Generating Multiple Passwords

var generator = new PasswordGenerator(16);

generator.Rules.Add(new PasswordComponent { CompType = PasswordComponentType.UpperCase, Quantity = 3 });
generator.Rules.Add(new PasswordComponent { CompType = PasswordComponentType.LowerCase, Quantity = 8 });
generator.Rules.Add(new PasswordComponent { CompType = PasswordComponentType.Digit, Quantity = 3 });
generator.Rules.Add(new PasswordComponent { CompType = PasswordComponentType.SpecialChar, Quantity = 2 });

// Generate 10 unique passwords
for (int i = 0; i < 10; i++)
{
    Console.WriteLine($"Password {i + 1}: {generator.GetPassword()}");
}

Password with Specific Security Requirements

// Corporate password policy: 14 chars, 2 uppercase, 8 lowercase, 2 digits, 2 special
var corpGenerator = new PasswordGenerator(14);

corpGenerator.Rules.Add(new PasswordComponent { CompType = PasswordComponentType.UpperCase, Quantity = 2 });
corpGenerator.Rules.Add(new PasswordComponent { CompType = PasswordComponentType.LowerCase, Quantity = 8 });
corpGenerator.Rules.Add(new PasswordComponent { CompType = PasswordComponentType.Digit, Quantity = 2 });
corpGenerator.Rules.Add(new PasswordComponent { CompType = PasswordComponentType.SpecialChar, Quantity = 2 });

string corporatePassword = corpGenerator.GetPassword();

Simple Random Password

// If no rules are specified, the generator fills with random letters
var simpleGenerator = new PasswordGenerator(10);
string simplePassword = simpleGenerator.GetPassword();
// Output will be random letters (upper and lowercase)

Check - Input Validation

The Check class provides various validation utilities for securing user input and validating data formats.

using ZidUtilities.CommonCode;

// Use Check class methods for validation
// (Specific examples depend on the methods available in Check.cs)

Extensions - Useful Extension Methods

The Extensions class provides helpful extension methods for common .NET types including string manipulation, collection operations, and data transformations.

using ZidUtilities.CommonCode;

// Example usage of extension methods
// (Specific examples depend on available extension methods)

Common Use Cases

Security & Encryption

• Encrypting sensitive configuration data
• Protecting user credentials before storage
• Securing file transfers and backups
• Computing file integrity checksums
• Generating secure temporary passwords

Password Management

• User password generation during registration
• Temporary password creation for password resets
• API key generation
• Token generation for authentication

Data Processing

• Comparing datasets for changes
• Validating and sanitizing user input
• Image format conversions
• Server-side data filtering

Security Best Practices

1. Always use AES for new applications - It's the industry standard
2. Use strong encryption keys - At least 12 characters with mixed case, numbers, and symbols
3. Use SHA256 or SHA512 for hashing - MD5 and SHA1 are deprecated
4. Store encryption keys securely - Never hard-code keys in source code
5. Use high iteration counts - 100,000+ iterations for password-based key derivation
6. Enable modern KDF - Set UseModernKdf = true for PBKDF2 support

Performance Considerations

• File Encryption: Large files are processed in 80KB chunks for optimal performance
• Hash Functions: SHA256 provides good balance of security and speed
• Password Generation: Minimal overhead, suitable for bulk generation
• Key Derivation: Higher iteration counts increase security but add computational cost