sreejithes/encrypto

Purpose and Public Entry Point

Encrypto is a Dart/Flutter security package exposing unified APIs for cryptography, password protection, JWTs, encoding, randomness, and platform-backed secret storage. Consumers import lib/encrypto.dart, which acts as the package façade and composes the feature modules under lib/.

API Facade and Service Boundaries

The public Encrypto surface delegates operations to focused domains rather than exposing platform code directly. This separates application-facing APIs from crypto implementations and storage adapters.

• lib/encrypto.dart

• lib/encryption/encryption.dart

• lib/storage/secure_storage.dart

Symmetric Encryption Pipeline

Encryption accepts plaintext and caller-supplied key material, produces an EncryptionResult, and supports AES variants and ChaCha20. Decryption consumes that result and compatible key material. AES-GCM is the intended default; AES-CBC is retained for compatibility.

• lib/encryption/aes.dart

• lib/encryption/chacha20.dart

• lib/encryption/encryption_result.dart

Asymmetric Cryptography

Separate implementations cover signing, key agreement, and RSA encryption/signature use cases. These form a distinct boundary from symmetric encryption because their key types, protocols, and failure modes differ.

• lib/asymmetric/asymmetric.dart

• lib/asymmetric/ed25519.dart

• lib/asymmetric/x25519.dart

• lib/asymmetric/rsa.dart

Integrity, Derivation, and Password Security

Hashing and HMAC provide integrity primitives; KDF implementations derive keys or password hashes. Password security is a higher-level workflow built around Argon2id hashing and verification, rather than requiring callers to manage raw KDF details.

• lib/hashing/hashing.dart

• lib/hmac/hmac.dart

• lib/kdf/argon2.dart

• lib/kdf/pbkdf2.dart

• lib/password/password_security.dart

Token, Encoding, and Security Utilities

JWT creation/verification uses the package’s crypto capabilities at the token boundary. Encoding converts binary crypto artifacts to transport/storage forms, while security utilities provide cryptographically secure randomness and constant-time equality for sensitive comparisons.

• lib/jwt/jwt.dart

• lib/encoding/encoding.dart

• lib/security/secure_random.dart

• lib/security/constant_time.dart

Platform Runtime and Persistent Secrets

The core library runs in Dart/Flutter. Secure persistence is delegated to native platform facilities—Android Keystore and iOS Keychain—through the storage abstraction, keeping secret-at-rest behavior outside general crypto APIs. The included example is a multi-platform Flutter host demonstrating package integration.

• lib/storage/secure_storage.dart

• example/lib/main.dart

• example/android/app/src/main/kotlin/com/example/encrypto_example/MainActivity.kt

• example/ios/Runner/AppDelegate.swift