Encrypted Storage (Silo)

/**
 * Create encrypted Silo transaction
 * @param attributes - Transaction attributes (must include data)
 * @param jwk - Wallet key for signing
 * @param siloUri - Silo URI containing encryption parameters
 * @returns Promise resolving to encrypted Transaction
 */
createSiloTransaction(
  attributes: Partial<CreateTransactionInterface>,
  jwk: JWKInterface,
  siloUri: string
): Promise<Transaction>;

import Arweave from "arweave";

const arweave = Arweave.init();
const key = await arweave.wallets.generate();

// Create Silo URI (in practice, this would come from a Silo provider)
const siloUri = "silo://access-key@encryption-key";

// Create encrypted transaction
const secretData = "This is confidential information";
const siloTransaction = await arweave.createSiloTransaction({
  data: secretData,
  tags: [
    { name: "Content-Type", value: "text/plain" },
    { name: "Encrypted", value: "true" }
  ]
}, key, siloUri);

await arweave.transactions.sign(siloTransaction, key);
await arweave.transactions.post(siloTransaction);

/**
 * Retrieve and decrypt data from Silo URI
 * @param siloURI - Silo URI containing access and encryption keys
 * @returns Promise resolving to decrypted data
 */
get(siloURI: string): Promise<Uint8Array>;

// Retrieve encrypted data using the same Silo URI
const siloUri = "silo://access-key@encryption-key";
const decryptedData = await arweave.silo.get(siloUri);

// Convert to string if it's text data
const textData = Arweave.utils.bufferToString(decryptedData);
console.log("Decrypted data:", textData);

/**
 * Decrypt Silo transaction data
 * @param transaction - Transaction containing encrypted Silo data
 * @param siloURI - Silo URI with decryption keys
 * @returns Promise resolving to decrypted data
 */
readTransactionData(transaction: Transaction, siloURI: string): Promise<Uint8Array>;

// Get Silo transaction and decrypt its data
const transactionId = "silo-transaction-id";
const transaction = await arweave.transactions.get(transactionId);
const siloUri = "silo://access-key@encryption-key";

const decryptedData = await arweave.silo.readTransactionData(transaction, siloUri);
const textData = Arweave.utils.bufferToString(decryptedData);
console.log("Decrypted transaction data:", textData);

/**
 * Parse Silo URI into access keys
 * @param siloURI - Silo URI to parse
 * @returns Promise resolving to SiloResource
 */
parseUri(siloURI: string): Promise<SiloResource>;

const siloUri = "silo://my-access-key@my-encryption-key";
const siloResource = await arweave.silo.parseUri(siloUri);

console.log("Access key:", siloResource.getAccessKey());
console.log("URI:", siloResource.getUri());
console.log("Encryption key length:", siloResource.getEncryptionKey().length);

class SiloResource {
  /**
   * Get the original Silo URI
   * @returns Silo URI string
   */
  getUri(): string;
  
  /**
   * Get the access key for Silo identification
   * @returns Access key string
   */
  getAccessKey(): string;
  
  /**
   * Get the encryption key for data encryption/decryption
   * @returns Encryption key as Uint8Array
   */
  getEncryptionKey(): Uint8Array;
}

// Store encrypted document with metadata
async function storeSecureDocument(
  document: string,
  metadata: { title: string; author: string; date: string },
  key: JWKInterface,
  siloUri: string
): Promise<string> {
  
  // Combine document and metadata
  const documentData = {
    content: document,
    metadata: metadata,
    timestamp: Date.now()
  };
  
  const jsonData = JSON.stringify(documentData);
  
  // Create encrypted Silo transaction
  const transaction = await arweave.createSiloTransaction({
    data: jsonData,
    tags: [
      { name: "Content-Type", value: "application/json" },
      { name: "Document-Type", value: "secure-document" },
      { name: "Author", value: metadata.author }
    ]
  }, key, siloUri);
  
  await arweave.transactions.sign(transaction, key);
  await arweave.transactions.post(transaction);
  
  return transaction.id;
}

// Usage
const key = await arweave.wallets.generate();
const siloUri = "silo://doc-access@doc-encryption-key";
const documentId = await storeSecureDocument(
  "This is a confidential document",
  { title: "Secret Report", author: "John Doe", date: "2024-01-01" },
  key,
  siloUri
);

// Share encrypted file with specific access controls
async function shareEncryptedFile(
  fileData: Uint8Array,
  fileName: string,
  fileType: string,
  key: JWKInterface
): Promise<{ transactionId: string; siloUri: string }> {
  
  // Generate unique encryption keys for this file
  const accessKey = generateRandomString(32);
  const encryptionKey = generateRandomString(64);
  const siloUri = `silo://${accessKey}@${encryptionKey}`;
  
  // Create encrypted transaction
  const transaction = await arweave.createSiloTransaction({
    data: fileData,
    tags: [
      { name: "Content-Type", value: fileType },
      { name: "File-Name", value: fileName },
      { name: "Encrypted", value: "true" }
    ]
  }, key, siloUri);
  
  await arweave.transactions.sign(transaction, key);
  await arweave.transactions.post(transaction);
  
  return {
    transactionId: transaction.id,
    siloUri: siloUri
  };
}

// Retrieve shared encrypted file
async function retrieveSharedFile(siloUri: string): Promise<{
  data: Uint8Array;
  fileName: string;
  fileType: string;
}> {
  // Decrypt the data
  const decryptedData = await arweave.silo.get(siloUri);
  
  // Parse Silo URI to get access key
  const siloResource = await arweave.silo.parseUri(siloUri);
  const accessKey = siloResource.getAccessKey();
  
  // Find transaction by Silo access key
  // (In practice, you'd store the transaction ID with the Silo URI)
  
  return {
    data: decryptedData,
    fileName: "retrieved-file",
    fileType: "application/octet-stream"
  };
}

// Create Silo with multiple access keys for team sharing
class TeamSilo {
  private baseUri: string;
  private teamMembers: Map<string, string> = new Map();
  
  constructor(baseAccessKey: string, baseEncryptionKey: string) {
    this.baseUri = `silo://${baseAccessKey}@${baseEncryptionKey}`;
  }
  
  // Add team member with their own access key
  addMember(memberId: string, memberAccessKey: string) {
    this.teamMembers.set(memberId, memberAccessKey);
  }
  
  // Create Silo URI for specific member
  getSiloUri(memberId: string): string {
    const memberAccessKey = this.teamMembers.get(memberId);
    if (!memberAccessKey) {
      throw new Error(`Member ${memberId} not found`);
    }
    
    const siloResource = parseManualSiloUri(this.baseUri);
    return `silo://${memberAccessKey}@${siloResource.encryptionKey}`;
  }
  
  // Store data accessible to all team members
  async storeTeamData(
    data: string,
    key: JWKInterface,
    metadata: { type: string; title: string }
  ): Promise<string> {
    const transaction = await arweave.createSiloTransaction({
      data: data,
      tags: [
        { name: "Content-Type", value: "text/plain" },
        { name: "Team-Resource", value: "true" },
        { name: "Resource-Type", value: metadata.type },
        { name: "Title", value: metadata.title }
      ]
    }, key, this.baseUri);
    
    await arweave.transactions.sign(transaction, key);
    await arweave.transactions.post(transaction);
    
    return transaction.id;
  }
}

// Usage
const teamSilo = new TeamSilo("team-access-key", "team-encryption-key");
teamSilo.addMember("alice", "alice-access-key");
teamSilo.addMember("bob", "bob-access-key");

// Alice stores data
const aliceKey = await arweave.wallets.generate();
const dataId = await teamSilo.storeTeamData(
  "Team meeting notes",
  aliceKey,
  { type: "notes", title: "Weekly Standup" }
);

// Bob retrieves data using his access
const bobSiloUri = teamSilo.getSiloUri("bob");
const decryptedNotes = await arweave.silo.get(bobSiloUri);

// ✅ Good: Generate cryptographically secure keys
function generateSecureSiloKeys(): { accessKey: string; encryptionKey: string } {
  const accessKey = crypto.getRandomValues(new Uint8Array(32));
  const encryptionKey = crypto.getRandomValues(new Uint8Array(64));
  
  return {
    accessKey: Arweave.utils.bufferTob64Url(accessKey),
    encryptionKey: Arweave.utils.bufferTob64Url(encryptionKey)
  };
}

// ❌ Bad: Predictable or weak keys
const weakKeys = {
  accessKey: "simple-key",
  encryptionKey: "another-simple-key"
};

// ✅ Good: Validate Silo URI format
function validateSiloUri(uri: string): boolean {
  const siloPattern = /^silo:\/\/[a-zA-Z0-9_-]+@[a-zA-Z0-9_-]+$/;
  return siloPattern.test(uri);
}

// ✅ Good: Implement access logging
async function auditedSiloAccess(siloUri: string): Promise<Uint8Array> {
  console.log(`Accessing Silo at ${Date.now()}: ${siloUri.substring(0, 20)}...`);
  
  try {
    const data = await arweave.silo.get(siloUri);
    console.log(`Successfully retrieved ${data.length} bytes`);
    return data;
  } catch (error) {
    console.error(`Failed to access Silo: ${error.message}`);
    throw error;
  }
}

/** Silo URI format: silo://access-key@encryption-key */
type SiloUri = string;

/** Silo protocol version identifier */
const SILO_VERSION: string = "0.1.0";

/** Default Silo URI scheme */
const SILO_SCHEME: string = "silo://";

// Utility functions for working with Silo URIs
function generateRandomString(length: number): string {
  const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_';
  const randomBytes = crypto.getRandomValues(new Uint8Array(length));
  return Array.from(randomBytes)
    .map(byte => chars[byte % chars.length])
    .join('');
}

function parseManualSiloUri(uri: string): { accessKey: string; encryptionKey: string } {
  const match = uri.match(/^silo:\/\/([^@]+)@(.+)$/);
  if (!match) {
    throw new Error("Invalid Silo URI format");
  }
  
  return {
    accessKey: match[1],
    encryptionKey: match[2]
  };
}