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

• Fixed Point-at-Infinity Vulnerability: PublicKey constructor now explicitly rejects point-at-infinity, preventing:
  • Invalid public key creation
  • Potential invalid XDAG addresses
  • Signature verification failures
  • Blockchain consensus issues

• Official Test Vectors: Added BIP-0032 (13 tests) and BIP-0039 (5 tests) official test vectors
• Security Tests: New comprehensive tests for point-at-infinity and digest state validation
• Total Coverage: 207 tests passing with 95%+ code coverage
• Quality: All test methods follow JUnit 5 naming conventions

• CHANGELOG.md: Complete version history and change tracking
• Test Coverage: Fixed BigInteger leading zero handling in hex conversion

This is a critical security update. All users should upgrade immediately.

<dependency>
    <groupId>io.xdag</groupId>
    <artifactId>xdagj-crypto</artifactId>
    <version>0.1.4</version>
</dependency>

implementation 'io.xdag:xdagj-crypto:0.1.4'

Requirements: Java 21+

import io.xdag.crypto.keys.*;

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

// XDAG compatibility (NEW v0.1.3): Create from x-coordinate + y-bit
PublicKey xdagKey = PublicKey.fromXCoordinate(xCoordinate, yBit);

import io.xdag.crypto.bip.*;

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

// NEW v0.1.3: 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);

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-CBC encryption (xdagj compatible)  
byte[] cipherText = Aes.encrypt(plainText, encryptionKey, iv);
byte[] decrypted = Aes.decrypt(cipherText, encryptionKey, iv);

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

• Cryptographic Standards: ECDSA (secp256k1), AES-CBC, 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

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

# 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

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

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

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

Built with ❤️ by the XDAG Development Team