NOVA SDK for Rust

A Rust SDK for interacting with NOVA secure file-sharing on NEAR blockchain. Provides encrypted, decentralized file storage using IPFS and NEAR smart contracts with group-based access control.

Features

🔐 AES-256-CBC Encryption - Client-side encryption for data privacy
🌐 IPFS Storage - Decentralized file storage via Pinata
⛓️ NEAR Blockchain - Immutable transaction records and access control
👥 Group Management - Fine-grained access control with member authorization
🔑 Key Rotation - Automatic key rotation on member revocation
🚀 Composite Operations - Simplified high-level workflows

Installation

Add to your Cargo.toml:

[dependencies]
nova-sdk-rs = "0.1.0"
tokio = { version = "1", features = ["full"] }

Quick Start

use nova_sdk_rs::{NovaSdk, CompositeUploadResult};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Initialize SDK
    let sdk = NovaSdk::new(
        "https://rpc.testnet.near.org",
        "nova-contract.testnet",
        "your_pinata_api_key",
        "your_pinata_secret_key"
    ).with_signer(
        "ed25519:your_private_key",
        "your-account.testnet"
    )?;

    // Upload encrypted file
    let result = sdk.composite_upload(
        "project_alpha",           // group_id
        "alice.testnet",           // user_id
        "Confidential data",       // data
        "report.txt"               // filename
    ).await?;

    println!("✅ Uploaded to IPFS: {}", result.cid);
    println!("📝 Transaction ID: {}", result.trans_id);
    println!("🔒 File Hash: {}", result.file_hash);

    // Retrieve and decrypt file
    let retrieved = sdk.composite_retrieve(
        "project_alpha",
        &result.cid
    ).await?;

    let decrypted = base64::engine::general_purpose::STANDARD
        .decode(&retrieved.decrypted_b64)?;
    let content = String::from_utf8(decrypted)?;
    
    println!("📄 Content: {}", content);

    Ok(())
}

Core Concepts

Groups

Groups provide isolated access control domains. Each group has:

A unique identifier (group_id)
An owner who manages membership
A shared encryption key
A list of authorized members

Access Control

// Register new group (owner only)
sdk.register_group("secure_vault").await?;

// Add members
sdk.add_group_member("secure_vault", "bob.testnet").await?;

// Check authorization
let authorized = sdk.is_authorized("secure_vault", "bob.testnet").await?;

// Revoke member (automatically rotates key)
sdk.revoke_group_member("secure_vault", "bob.testnet").await?;

Encryption

All data is encrypted client-side using AES-256-CBC:

256-bit symmetric keys
Random IV per encryption
PKCS7 padding
Keys stored encrypted on blockchain

Transaction Recording

Every file operation creates an immutable blockchain record:

let trans_id = sdk.record_transaction(
    "my_group",
    "alice.testnet",
    "file_hash_sha256",
    "QmIPFSHash"
).await?;

// Query group transactions
let txs = sdk.get_transactions_for_group("my_group", "alice.testnet").await?;

API Overview

Initialization

NovaSdk::new() - Create SDK instance
with_signer() - Attach NEAR account credentials

Group Management

register_group() - Create new group
add_group_member() - Grant access to user
revoke_group_member() - Revoke access and rotate key
is_authorized() - Check user authorization

Key Management

store_group_key() - Store encryption key
get_group_key() - Retrieve key (authorized users only)

File Operations

composite_upload() - Encrypt, upload to IPFS, record transaction
composite_retrieve() - Fetch from IPFS, decrypt
record_transaction() - Record file metadata on blockchain
get_transactions_for_group() - Query transaction history

Utilities

get_balance() - Check NEAR account balance
transfer_tokens() - Transfer NEAR tokens

Environment Setup

For testing and development, set these environment variables:

# Required for integration tests
TEST_NEAR_ACCOUNT_ID=your-account.testnet
TEST_NEAR_PRIVATE_KEY=ed25519:your_private_key
PINATA_API_KEY=your_pinata_key
PINATA_SECRET_KEY=your_pinata_secret

Create a .env file:

TEST_NEAR_ACCOUNT_ID=alice.testnet
TEST_NEAR_PRIVATE_KEY=ed25519:...
PINATA_API_KEY=...
PINATA_SECRET_KEY=...

Testing

# Run unit tests
cargo test

# Run with integration tests (requires .env setup)
cargo test -- --include-ignored

# Run specific test
cargo test test_composite_upload

Error Handling

The SDK uses a custom NovaError enum:

use nova_sdk_rs::NovaError;

match sdk.get_group_key("my_group", "user.testnet").await {
    Ok(key) => println!("Key: {}", key),
    Err(NovaError::Near(msg)) => eprintln!("RPC error: {}", msg),
    Err(NovaError::InvalidKey) => eprintln!("Invalid encryption key"),
    Err(NovaError::ParseAccount) => eprintln!("Invalid account ID"),
    Err(NovaError::Signing(msg)) => eprintln!("Signing failed: {}", msg),
}

Security Considerations

⚠️ Important Security Notes:

Private Keys - Never commit private keys to version control
Key Storage - Store encryption keys securely
IPFS Privacy - IPFS content is public; encryption is essential
Access Control - Verify user authorization before operations
Key Rotation - Revoked members cannot decrypt new content

Examples

See the examples directory for complete working examples:

simple_upload.rs - Basic file upload/download
group_management.rs - Managing groups and members
key_rotation.rs - Handling member revocation

Contributing

Contributions are welcome! Please:

Fork the repository
Create a feature branch
Add tests for new functionality
Ensure all tests pass (cargo test)
Submit a pull request

nova-sdk-rs 0.2.0