webassembly/ENHANCEMENT_SPEC.md

WebAssembly Cryptography Module Enhancement Specification

1. Executive Summary

This document outlines the architectural vision for extending the WebAssembly Cryptography Module with a Command Line Interface (CLI), Rhai scripting capabilities, and messaging system integration. These enhancements will transform the module from a browser-focused library into a versatile cryptographic toolkit that can operate across multiple contexts while maintaining its existing WebAssembly functionality.

2. System Overview

2.1 Current System

The existing WebAssembly Cryptography Module provides:

• Secure key management with encrypted storage
• Asymmetric cryptography operations (ECDSA)
• Symmetric encryption (ChaCha20Poly1305)
• Ethereum wallet functionality
• Browser integration via WebAssembly

2.2 Enhanced System Vision

The enhanced system will extend these capabilities to:

• Provide command-line access to all cryptographic functions
• Enable automation through scripting
• Support remote operation via messaging
• Maintain WebAssembly compatibility

3. Architecture Overview

3.1 Component Architecture

┌─────────────────────────────────────────────────────────────┐
│                                                             │
│                    User Interaction Layer                   │
│                                                             │
├───────────────────┐                     ┌─────────────────┐ │
│                   │                     │                 │ │
│  WebAssembly UI   │                     │  CLI Interface  │ │
│                   │                     │                 │ │
└─────────┬─────────┘                     └────────┬────────┘ │
          │                                        │          │
          └────────────────┐     ┌─────────────────┘          │
                           │     │                            │
                           ▼     ▼                            │
┌─────────────────────────────────────────────────────────────┤
│                                                             │
│                   Cryptographic Core API                    │
│                                                             │
├─────────────────────────────────────────────────────────────┤
│                                                             │
│ ┌─────────────────┐  ┌────────────────┐  ┌───────────────┐ │
│ │                 │  │                │  │               │ │
│ │  Key Management │  │ Cryptographic  │  │   Ethereum    │ │
│ │                 │  │   Operations   │  │    Wallet     │ │
│ │                 │  │                │  │               │ │
│ └─────────────────┘  └────────────────┘  └───────────────┘ │
│                                                             │
└─────────────────────────────────────────────────────────────┘
                      ▲
                      │
          ┌───────────┴───────────┐
          │                       │
┌─────────┴─────────┐             │
│                   │             │
│  Rhai Scripting   │◄────────────┘
│      Engine       │
│                   │◄────────────┐
└─────────┬─────────┘             │
          │                       │
          ▼                       │
┌─────────────────────┐           │
│                     │           │
│  Messaging System   │───────────┘
│                     │
│                     │
└─────────────────────┘

3.2 Logical Architecture

graph TD
    User[User] --> CLI[CLI Interface]
    User --> WebUI[Web UI]
    CLI --> Core[Cryptographic Core]
    WebUI --> WASM[WebAssembly Module]
    WASM --> Core
    CLI --> ScriptEngine[Rhai Script Engine]
    ScriptEngine --> Core
    CLI --> Messaging[Messaging System]
    Messaging --> ScriptEngine
    RemoteSystems[Remote Systems] --> Messaging
    
    subgraph "Core Functionality"
        Core --> KeyMgmt[Key Management]
        Core --> CryptoOps[Cryptographic Operations]
        Core --> EthWallet[Ethereum Wallet]
        Core --> Storage[Secure Storage]
    end

4. Component Specifications

4.1 Command Line Interface (CLI)

4.1.1 Purpose

Provide a command-line interface to all cryptographic functions, enabling scripting, automation, and integration with other tools.

4.1.2 Key Features

• Command categories for different functional areas
• Interactive and non-interactive modes
• Configuration management
• Comprehensive help system

4.1.3 Command Structure

crypto-cli [OPTIONS] <COMMAND>

COMMANDS:
  key         Key management operations
  crypto      Cryptographic operations
  ethereum    Ethereum wallet operations
  script      Execute Rhai scripts
  listen      Listen for scripts via messaging
  shell       Start interactive shell
  help        Print help information

4.2 Rhai Scripting Engine

4.2.1 Purpose

Enable automation of cryptographic operations through a secure scripting language.

4.2.2 Key Features

• Access to all cryptographic functions
• Sandboxed execution environment
• Script validation and error handling
• Support for conditional logic and data processing

4.2.3 Script Flow Example

sequenceDiagram
    participant User
    participant CLI
    participant ScriptEngine
    participant CryptoCore
    
    User->>CLI: Execute script
    CLI->>ScriptEngine: Load and validate script
    ScriptEngine->>CryptoCore: Create key space
    CryptoCore-->>ScriptEngine: Success
    ScriptEngine->>CryptoCore: Create keypair
    CryptoCore-->>ScriptEngine: Success
    ScriptEngine->>CryptoCore: Sign message
    CryptoCore-->>ScriptEngine: Signature
    ScriptEngine-->>CLI: Script result
    CLI-->>User: Display result

4.3 Messaging System

4.3.1 Purpose

Enable remote execution of cryptographic operations through a secure messaging system.

4.3.2 Options

Option A: Mycelium

• Peer-to-peer architecture
• End-to-end encryption by default
• NAT traversal capabilities
• Rust native implementation

Option B: NATS

• Client-server architecture
• High performance and scalability
• Mature ecosystem
• Extensive documentation

4.3.3 Messaging Flow

sequenceDiagram
    participant RemoteSystem
    participant MessagingSystem
    participant CLI
    participant ScriptEngine
    participant CryptoCore
    
    RemoteSystem->>MessagingSystem: Send script
    MessagingSystem->>CLI: Deliver script
    CLI->>ScriptEngine: Execute script
    ScriptEngine->>CryptoCore: Perform operations
    CryptoCore-->>ScriptEngine: Operation results
    ScriptEngine-->>CLI: Script result
    CLI->>MessagingSystem: Send result
    MessagingSystem->>RemoteSystem: Deliver result

5. Data Flows

5.1 CLI Operation Flow

flowchart TD
    A[User Input] --> B{Command Type}
    B -->|Key Management| C[Process Key Command]
    B -->|Cryptographic| D[Process Crypto Command]
    B -->|Ethereum| E[Process Ethereum Command]
    B -->|Script| F[Process Script Command]
    B -->|Messaging| G[Process Messaging Command]
    
    C --> H[Execute Core API]
    D --> H
    E --> H
    F --> I[Execute Script Engine]
    I --> H
    G --> J[Execute Messaging System]
    J --> I
    
    H --> K[Return Result]
    K --> L[Format Output]
    L --> M[Display to User]

5.2 Script Execution Flow

flowchart TD
    A[Script Input] --> B[Parse Script]
    B --> C[Validate Script]
    C --> D{Valid?}
    D -->|No| E[Report Error]
    D -->|Yes| F[Initialize Sandbox]
    F --> G[Execute Script]
    G --> H{Error?}
    H -->|Yes| I[Handle Error]
    H -->|No| J[Process Result]
    I --> K[Return Error]
    J --> L[Return Result]

5.3 Messaging System Flow

flowchart TD
    A[Remote System] --> B[Send Message]
    B --> C[Messaging Transport]
    C --> D[Receive Message]
    D --> E[Validate Message]
    E --> F{Valid?}
    F -->|No| G[Reject Message]
    F -->|Yes| H[Extract Script]
    H --> I[Execute Script]
    I --> J[Generate Result]
    J --> K[Format Response]
    K --> L[Send Response]
    L --> M[Messaging Transport]
    M --> N[Remote System]

6. Security Architecture

6.1 Security Layers

flowchart TD
    A[User/System Input] --> B[Input Validation]
    B --> C[Authentication]
    C --> D[Authorization]
    D --> E[Sandboxed Execution]
    E --> F[Cryptographic Operations]
    F --> G[Secure Storage]
    
    H[Security Monitoring] --> B
    H --> C
    H --> D
    H --> E
    H --> F
    H --> G

6.2 Key Security Measures

• Input Validation: All inputs are validated before processing
• Authentication: Users and systems must authenticate before accessing sensitive operations
• Authorization: Access to operations is controlled based on authentication
• Sandboxing: Scripts execute in a restricted environment
• Encryption: All sensitive data is encrypted at rest and in transit
• Secure Storage: Keys are stored in encrypted form
• Monitoring: Security events are logged and monitored

7. Integration Points

7.1 WebAssembly Integration

The enhanced system will maintain compatibility with the existing WebAssembly module, allowing browser-based applications to continue using the cryptographic functionality.

7.2 CLI Integration

The CLI will integrate with the operating system's command-line environment, enabling integration with shell scripts and other command-line tools.

7.3 Messaging Integration

The messaging system will provide integration points for remote systems to send scripts and receive results, enabling distributed cryptographic operations.

8. Deployment Architecture

8.1 Standalone Deployment

flowchart TD
    A[User] --> B[CLI Application]
    B --> C[Local File System]
    B --> D[Local Cryptographic Operations]

8.2 Networked Deployment

flowchart TD
    A[User] --> B[CLI Application]
    B --> C[Local File System]
    B --> D[Local Cryptographic Operations]
    B <--> E[Messaging System]
    F[Remote System] <--> E
    G[Remote System] <--> E

8.3 Web Deployment

flowchart TD
    A[User] --> B[Web Browser]
    B --> C[WebAssembly Module]
    C --> D[Browser Storage]
    C --> E[Browser Cryptographic Operations]

9. Decision Matrix: Mycelium vs. NATS

Criteria	Mycelium	NATS
Architecture	Peer-to-peer	Client-server
Decentralization	High	Low
Security	End-to-end encryption by default	TLS support
NAT Traversal	Built-in	Requires configuration
Maturity	Newer project	Established project
Documentation	Limited	Extensive
Performance	Good for P2P scenarios	Optimized for high throughput
Deployment Complexity	No central server needed	Requires server setup
Language Support	Rust native	Multiple language clients

10. Implementation Roadmap

10.1 Milestones

1. CLI Core Implementation Complete

   • Basic CLI structure implemented
   • All cryptographic functions accessible via CLI
   • Interactive shell functional

2. Rhai Scripting Integration Complete

   • Script execution functional
   • All cryptographic functions accessible via scripts
   • Sandboxing implemented

3. Messaging System Integration Complete

   • Selected messaging system integrated
   • Remote script execution functional
   • Security measures implemented

4. Project Complete

   • All tests passing
   • Documentation complete
   • Release candidate ready

11. Conclusion

The enhanced WebAssembly Cryptography Module will provide a versatile cryptographic toolkit that can operate across multiple contexts, from browser applications to command-line tools to distributed systems. By adding CLI capabilities, Rhai scripting, and messaging system integration, the module will support a wider range of use cases while maintaining its existing WebAssembly functionality.

The choice between Mycelium and NATS for the messaging system will depend on specific requirements for decentralization, security, and deployment complexity. Both options provide viable paths forward, with different trade-offs in terms of architecture and capabilities.