XDAG Java Cryptographic Library

A production-grade cryptographic library for XDAG blockchain applications with focus on security, performance, and developer experience.

🆕 What's New in v0.1.1

• Enhanced XDAG Compatibility: Added PublicKey.fromXCoordinate() method for XDAG's 32-byte x-coordinate + y-bit format
• Simplified HD Wallet API: Direct key pair generation from mnemonic phrases
• Improved Documentation: Fixed Javadoc warnings and enhanced API documentation
• Optimized Dependencies: Removed unnecessary configurations for better performance

📦 Installation

Maven

<dependency>
    <groupId>io.xdag</groupId>
    <artifactId>xdagj-crypto</artifactId>
    <version>0.1.1</version>
</dependency>

Gradle

implementation 'io.xdag:xdagj-crypto:0.1.1'

Requirements: Java 21+

🚀 Quick Start

1. Basic Key Operations

import io.xdag.crypto.keys.*;

// Generate key pair and address
ECKeyPair keyPair = ECKeyPair.generate();
String address = keyPair.toBase58Address();

// XDAG compatibility (NEW v0.1.1): Create from x-coordinate + y-bit
PublicKey xdagKey = PublicKey.fromXCoordinate(xCoordinate, yBit);

2. HD Wallet (BIP32/44)

import io.xdag.crypto.bip.*;

// Generate mnemonic and derive key pairs
String mnemonic = Bip39Mnemonic.generateString();

// NEW v0.1.1: Simplified API for basic use cases
ECKeyPair keyPair = Bip44Wallet.createKeyPairFromMnemonic(mnemonic);

// Advanced: BIP44 derivation path m/44'/586'/0'/0/0
Bytes seed = Bip39Mnemonic.toSeed(mnemonic);
Bip32Key masterKey = Bip44Wallet.createMasterKey(seed.toArrayUnsafe());
Bip32Key accountKey = Bip44Wallet.deriveXdagKey(masterKey, 0, 0);

3. Digital Signatures & Encryption

import io.xdag.crypto.keys.*;
import io.xdag.crypto.encryption.Aes;

// Sign and verify messages  
Signature signature = Signer.sign(messageHash, keyPair);
boolean valid = Signer.verify(messageHash, signature, keyPair.getPublicKey());

// AES-256-GCM encryption
Bytes cipherText = Aes.encrypt(plainText, encryptionKey, nonce);
Bytes decrypted = Aes.decrypt(cipherText, encryptionKey, nonce);

🏗️ Core Features

• Elliptic Curve Cryptography: ECDSA with secp256k1 curve
• Hierarchical Deterministic Wallets: BIP32/BIP39/BIP44 implementation
• Symmetric Encryption: AES-256-GCM authenticated encryption
• Hash Functions: SHA-256, RIPEMD-160, HMAC operations
• Address Generation: XDAG-compatible Base58 addresses
• XDAG Integration: Native support for XDAG public key formats

🛡️ Security

• Cryptographic Standards: ECDSA (secp256k1), AES-256-GCM, SHA-256, PBKDF2
• Constant-Time Operations: Prevents timing attacks
• Secure Random Generation: Platform-optimal entropy sources
• Input Validation: Comprehensive validation with detailed error messages
• Thread Safety: All operations are thread-safe by design

🔗 Dependencies

• Consensys Tuweni: High-performance byte operations
• Bouncy Castle: Cryptographic implementations
• SLF4J: Logging framework

📊 Key Features v0.1.1

New XDAG Compatibility

// Create public key from XDAG's x-coordinate + y-bit format
PublicKey xdagKey = PublicKey.fromXCoordinate(xCoordinate, yBit);

Simplified HD Wallet API

// Direct key pair generation from mnemonic
ECKeyPair keyPair = Bip44Wallet.createKeyPairFromMnemonic(mnemonic);

For complete API documentation, see JavaDoc

🏗️ Building from Source

# Prerequisites: Java 21+, Maven 3.8+
git clone https://github.com/XDagger/xdagj-crypto.git
cd xdagj-crypto

# Run tests and build
mvn clean test package

🤝 Contributing

We welcome contributions! Please read our Contributing Guidelines for details.

Development Standards:

• Code Coverage: Minimum 95% line coverage
• Documentation: Comprehensive Javadoc for all public APIs
• Testing: Unit tests for all functionality
• Security: Regular dependency vulnerability scanning

📄 License

Licensed under the MIT License - see LICENSE file for details.

🔗 Related Projects

• xdagj: Java implementation of XDAG blockchain
• xdagj-p2p: Peer-to-peer networking layer

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Built with ❤️ by the XDAG Development Team