@bsv/wallet-toolbox/src/sdk/__test/PrivilegedKeyManager.test.ts

BRC100 conforming wallet, wallet storage and wallet signer components

import { PrivilegedKeyManager } from '../PrivilegedKeyManager'
import { Utils, PrivateKey, Hash, Random } from '@bsv/sdk'

const sampleData = [3, 1, 4, 1, 5, 9]

// A helper function to get a 32-byte hex
function getRandom32ByteHex(): string {
  const rawBytes = Random(32)
  return Utils.toHex(rawBytes)
}

describe('PrivilegedKeyManager', () => {
  it('Validates the BRC-3 compliance vector', async () => {
    const wallet = new PrivilegedKeyManager(async () => new PrivateKey(1))
    const { valid } = await wallet.verifySignature({
      data: Utils.toArray('BRC-3 Compliance Validated!', 'utf8'),
      signature: [
        48, 68, 2, 32, 43, 34, 58, 156, 219, 32, 50, 70, 29, 240, 155, 137, 88, 60, 200, 95, 243, 198, 201, 21, 56, 82,
        141, 112, 69, 196, 170, 73, 156, 6, 44, 48, 2, 32, 118, 125, 254, 201, 44, 87, 177, 170, 93, 11, 193, 134, 18,
        70, 9, 31, 234, 27, 170, 177, 54, 96, 181, 140, 166, 196, 144, 14, 230, 118, 106, 105
      ],
      protocolID: [2, 'BRC3 Test'],
      keyID: '42',
      counterparty: '0294c479f762f6baa97fbcd4393564c1d7bd8336ebd15928135bbcf575cd1a71a1'
    })
    expect(valid).toBe(true)
    await wallet.destroyKey()
  })
  it('Validates the BRC-2 HMAC compliance vector', async () => {
    const wallet = new PrivilegedKeyManager(
      async () => new PrivateKey('6a2991c9de20e38b31d7ea147bf55f5039e4bbc073160f5e0d541d1f17e321b8', 'hex')
    )
    const { valid } = await wallet.verifyHmac({
      data: Utils.toArray('BRC-2 HMAC Compliance Validated!', 'utf8'),
      hmac: [
        81, 240, 18, 153, 163, 45, 174, 85, 9, 246, 142, 125, 209, 133, 82, 76, 254, 103, 46, 182, 86, 59, 219, 61, 126,
        30, 176, 232, 233, 100, 234, 14
      ],
      protocolID: [2, 'BRC2 Test'],
      keyID: '42',
      counterparty: '0294c479f762f6baa97fbcd4393564c1d7bd8336ebd15928135bbcf575cd1a71a1'
    })
    expect(valid).toBe(true)
    await wallet.destroyKey()
  })
  it('Validates the BRC-2 Encryption compliance vector', async () => {
    const wallet = new PrivilegedKeyManager(
      async () => new PrivateKey('6a2991c9de20e38b31d7ea147bf55f5039e4bbc073160f5e0d541d1f17e321b8', 'hex')
    )
    const { plaintext } = await wallet.decrypt({
      ciphertext: [
        252, 203, 216, 184, 29, 161, 223, 212, 16, 193, 94, 99, 31, 140, 99, 43, 61, 236, 184, 67, 54, 105, 199, 47, 11,
        19, 184, 127, 2, 165, 125, 9, 188, 195, 196, 39, 120, 130, 213, 95, 186, 89, 64, 28, 1, 80, 20, 213, 159, 133,
        98, 253, 128, 105, 113, 247, 197, 152, 236, 64, 166, 207, 113, 134, 65, 38, 58, 24, 127, 145, 140, 206, 47, 70,
        146, 84, 186, 72, 95, 35, 154, 112, 178, 55, 72, 124
      ],
      protocolID: [2, 'BRC2 Test'],
      keyID: '42',
      counterparty: '0294c479f762f6baa97fbcd4393564c1d7bd8336ebd15928135bbcf575cd1a71a1'
    })
    expect(Utils.toUTF8(plaintext)).toEqual('BRC-2 Encryption Compliance Validated!')
    await wallet.destroyKey()
  })
  it('Encrypts messages decryptable by the counterparty', async () => {
    const userKey = PrivateKey.fromRandom()
    const counterpartyKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const counterparty = new PrivilegedKeyManager(async () => counterpartyKey)
    const { ciphertext } = await user.encrypt({
      plaintext: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: counterpartyKey.toPublicKey().toString()
    })
    const { plaintext } = await counterparty.decrypt({
      ciphertext,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: userKey.toPublicKey().toString()
    })
    expect(plaintext).toEqual(sampleData)
    expect(ciphertext).not.toEqual(plaintext)
    await user.destroyKey()
    await counterparty.destroyKey()
  })
  it('Fails to decryupt messages for the wrong protocol, key, and counterparty', async () => {
    const userKey = PrivateKey.fromRandom()
    const counterpartyKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const counterparty = new PrivilegedKeyManager(async () => counterpartyKey)
    const { ciphertext } = await user.encrypt({
      plaintext: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: counterpartyKey.toPublicKey().toString()
    })
    await expect(
      async () =>
        await counterparty.decrypt({
          ciphertext,
          protocolID: [1, 'tests'],
          keyID: '4',
          counterparty: userKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await expect(
      async () =>
        await counterparty.decrypt({
          ciphertext,
          protocolID: [2, 'tests'],
          keyID: '5',
          counterparty: userKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await expect(
      async () =>
        await counterparty.decrypt({
          ciphertext,
          protocolID: [2, 'tests'],
          keyID: '4',
          counterparty: counterpartyKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await user.destroyKey()
    await counterparty.destroyKey()
  })
  it('Correctly derives keys for a counterparty', async () => {
    const userKey = PrivateKey.fromRandom()
    const counterpartyKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const counterparty = new PrivilegedKeyManager(async () => counterpartyKey)
    const { publicKey: identityKey } = await user.getPublicKey({
      identityKey: true
    })
    expect(identityKey).toEqual(userKey.toPublicKey().toString())
    const { publicKey: derivedForCounterparty } = await user.getPublicKey({
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: counterpartyKey.toPublicKey().toString()
    })
    const { publicKey: derivedByCounterparty } = await counterparty.getPublicKey({
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: userKey.toPublicKey().toString(),
      forSelf: true
    })
    expect(derivedForCounterparty).toEqual(derivedByCounterparty)
    await user.destroyKey()
    await counterparty.destroyKey()
  })
  it('Signs messages verifiable by the counterparty', async () => {
    const userKey = PrivateKey.fromRandom()
    const counterpartyKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const counterparty = new PrivilegedKeyManager(async () => counterpartyKey)
    const { signature } = await user.createSignature({
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: counterpartyKey.toPublicKey().toString()
    })
    const { valid } = await counterparty.verifySignature({
      signature,
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: userKey.toPublicKey().toString()
    })
    expect(valid).toEqual(true)
    expect(signature.length).not.toEqual(0)
    await user.destroyKey()
    await counterparty.destroyKey()
  })
  it('Directly signs hash of message verifiable by the counterparty', async () => {
    const userKey = PrivateKey.fromRandom()
    const counterpartyKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const counterparty = new PrivilegedKeyManager(async () => counterpartyKey)
    const { signature } = await user.createSignature({
      hashToDirectlySign: Hash.sha256(sampleData),
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: counterpartyKey.toPublicKey().toString()
    })
    const { valid } = await counterparty.verifySignature({
      signature,
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: userKey.toPublicKey().toString()
    })
    expect(valid).toEqual(true)
    const { valid: hashValid } = await counterparty.verifySignature({
      signature,
      hashToDirectlyVerify: Hash.sha256(sampleData),
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: userKey.toPublicKey().toString()
    })
    expect(hashValid).toEqual(true)
    expect(signature.length).not.toEqual(0)
    await user.destroyKey()
    await counterparty.destroyKey()
  })
  it('Fails to verify signature for the wrong data, protocol, key, and counterparty', async () => {
    const userKey = PrivateKey.fromRandom()
    const counterpartyKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const counterparty = new PrivilegedKeyManager(async () => counterpartyKey)
    const { signature } = await user.createSignature({
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: counterpartyKey.toPublicKey().toString()
    })
    await expect(
      async () =>
        await counterparty.verifySignature({
          signature,
          data: [0, ...sampleData],
          protocolID: [2, 'tests'],
          keyID: '4',
          counterparty: userKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await expect(
      async () =>
        await counterparty.verifySignature({
          signature,
          data: sampleData,
          protocolID: [2, 'wrong'],
          keyID: '4',
          counterparty: userKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await expect(
      async () =>
        await counterparty.verifySignature({
          signature,
          data: sampleData,
          protocolID: [2, 'tests'],
          keyID: '2',
          counterparty: userKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await expect(
      async () =>
        await counterparty.verifySignature({
          signature,
          data: sampleData,
          protocolID: [2, 'tests'],
          keyID: '4',
          counterparty: counterpartyKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await user.destroyKey()
    await counterparty.destroyKey()
  })
  it('Computes HMAC over messages verifiable by the counterparty', async () => {
    const userKey = PrivateKey.fromRandom()
    const counterpartyKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const counterparty = new PrivilegedKeyManager(async () => counterpartyKey)
    const { hmac } = await user.createHmac({
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: counterpartyKey.toPublicKey().toString()
    })
    const { valid } = await counterparty.verifyHmac({
      hmac,
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: userKey.toPublicKey().toString()
    })
    expect(valid).toEqual(true)
    expect(hmac.length).toEqual(32)
    await user.destroyKey()
    await counterparty.destroyKey()
  })
  it('Fails to verify HMAC for the wrong data, protocol, key, and counterparty', async () => {
    const userKey = PrivateKey.fromRandom()
    const counterpartyKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const counterparty = new PrivilegedKeyManager(async () => counterpartyKey)
    const { hmac } = await user.createHmac({
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: counterpartyKey.toPublicKey().toString()
    })
    await expect(
      async () =>
        await counterparty.verifyHmac({
          hmac,
          data: [0, ...sampleData],
          protocolID: [2, 'tests'],
          keyID: '4',
          counterparty: userKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await expect(
      async () =>
        await counterparty.verifyHmac({
          hmac,
          data: sampleData,
          protocolID: [2, 'wrong'],
          keyID: '4',
          counterparty: userKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await expect(
      async () =>
        await counterparty.verifyHmac({
          hmac,
          data: sampleData,
          protocolID: [2, 'tests'],
          keyID: '2',
          counterparty: userKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await expect(
      async () =>
        await counterparty.verifyHmac({
          hmac,
          data: sampleData,
          protocolID: [2, 'tests'],
          keyID: '4',
          counterparty: counterpartyKey.toPublicKey().toString()
        })
    ).rejects.toThrow()
    await user.destroyKey()
    await counterparty.destroyKey()
  })
  it('Uses anyone for creating signatures and self for other operations if no counterparty is provided', async () => {
    const userKey = PrivateKey.fromRandom()
    const user = new PrivilegedKeyManager(async () => userKey)
    const { hmac } = await user.createHmac({
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4'
    })
    const { valid: hmacValid } = await user.verifyHmac({
      hmac,
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4'
    })
    expect(hmacValid).toEqual(true)
    const { valid: explicitSelfHmacValid } = await user.verifyHmac({
      hmac,
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: 'self'
    })
    expect(explicitSelfHmacValid).toEqual(true)
    expect(hmac.length).toEqual(32)
    const { signature: anyoneSig } = await user.createSignature({
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4'
      // counterparty=anyone is implicit for creating signatures
    })
    const anyone = new PrivilegedKeyManager(async () => new PrivateKey(1))
    const { valid: anyoneSigValid } = await anyone.verifySignature({
      signature: anyoneSig,
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: userKey.toPublicKey().toString()
    })
    expect(anyoneSigValid).toEqual(true)
    const { signature: selfSig } = await user.createSignature({
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: 'self'
    })
    const { valid: selfSigValid } = await user.verifySignature({
      signature: selfSig,
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4'
      // Self is implicit when verifying signatures
    })
    expect(selfSigValid).toEqual(true)
    const { valid: explicitSelfSigValid } = await user.verifySignature({
      signature: selfSig,
      data: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: 'self'
    })
    expect(explicitSelfSigValid).toEqual(true)
    const { publicKey } = await user.getPublicKey({
      protocolID: [2, 'tests'],
      keyID: '4'
    })
    const { publicKey: explicitSelfPublicKey } = await user.getPublicKey({
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: 'self'
    })
    expect(publicKey).toEqual(explicitSelfPublicKey)
    const { ciphertext } = await user.encrypt({
      plaintext: sampleData,
      protocolID: [2, 'tests'],
      keyID: '4'
    })
    const { plaintext } = await user.decrypt({
      ciphertext,
      protocolID: [2, 'tests'],
      keyID: '4'
    })
    const { plaintext: explicitSelfPlaintext } = await user.decrypt({
      ciphertext,
      protocolID: [2, 'tests'],
      keyID: '4',
      counterparty: 'self'
    })
    expect(plaintext).toEqual(explicitSelfPlaintext)
    expect(plaintext).toEqual(sampleData)
    await user.destroyKey()
    await anyone.destroyKey()
  })
  describe('PrivilegedKeyManager Key Linkage Revelation', () => {
    it('Validates the revealCounterpartyKeyLinkage function', async () => {
      // Initialize keys
      const proverKey = PrivateKey.fromRandom()
      const counterpartyKey = PrivateKey.fromRandom()
      const verifierKey = PrivateKey.fromRandom()

      // Initialize wallets
      const proverWallet = new PrivilegedKeyManager(async () => proverKey)
      const verifierWallet = new PrivilegedKeyManager(async () => verifierKey)

      // Prover reveals counterparty key linkage
      const revelation = await proverWallet.revealCounterpartyKeyLinkage({
        counterparty: counterpartyKey.toPublicKey().toString(),
        verifier: verifierKey.toPublicKey().toString()
      })

      // Verifier decrypts the encrypted linkage
      const { plaintext: linkage } = await verifierWallet.decrypt({
        ciphertext: revelation.encryptedLinkage,
        protocolID: [2, 'counterparty linkage revelation'],
        keyID: revelation.revelationTime,
        counterparty: proverKey.toPublicKey().toString()
      })

      // Compute expected linkage
      const expectedLinkage = proverKey.deriveSharedSecret(counterpartyKey.toPublicKey()).encode(true)

      // Compare linkage and expectedLinkage
      expect(linkage).toEqual(expectedLinkage)
      await proverWallet.destroyKey()
      await verifierWallet.destroyKey()
    })

    it('Validates the revealSpecificKeyLinkage function', async () => {
      // Initialize keys
      const proverKey = PrivateKey.fromRandom()
      const counterpartyKey = PrivateKey.fromRandom()
      const verifierKey = PrivateKey.fromRandom()

      // Initialize wallets
      const proverWallet = new PrivilegedKeyManager(async () => proverKey)
      const verifierWallet = new PrivilegedKeyManager(async () => verifierKey)

      const protocolID: [0 | 1 | 2, string] = [0, 'tests']
      const keyID = 'test key id'

      // Prover reveals specific key linkage
      const revelation = await proverWallet.revealSpecificKeyLinkage({
        counterparty: counterpartyKey.toPublicKey().toString(),
        verifier: verifierKey.toPublicKey().toString(),
        protocolID,
        keyID
      })

      // Verifier decrypts the encrypted linkage
      const { plaintext: linkage } = await verifierWallet.decrypt({
        ciphertext: revelation.encryptedLinkage,
        protocolID: [2, `specific linkage revelation ${protocolID[0]} ${protocolID[1]}`],
        keyID,
        counterparty: proverKey.toPublicKey().toString()
      })

      // Compute expected linkage
      const sharedSecret = proverKey.deriveSharedSecret(counterpartyKey.toPublicKey()).encode(true)

      // Function to compute the invoice number
      const computeInvoiceNumber = function (protocolID, keyID) {
        const securityLevel = protocolID[0]
        if (!Number.isInteger(securityLevel) || securityLevel < 0 || securityLevel > 2) {
          throw new Error('Protocol security level must be 0, 1, or 2')
        }
        const protocolName = protocolID[1].toLowerCase().trim()
        if (keyID.length > 800) {
          throw new Error('Key IDs must be 800 characters or less')
        }
        if (keyID.length < 1) {
          throw new Error('Key IDs must be 1 character or more')
        }
        if (protocolName.length > 400) {
          throw new Error('Protocol names must be 400 characters or less')
        }
        if (protocolName.length < 5) {
          throw new Error('Protocol names must be 5 characters or more')
        }
        if (protocolName.includes('  ')) {
          throw new Error('Protocol names cannot contain multiple consecutive spaces ("  ")')
        }
        if (!/^[a-z0-9 ]+$/g.test(protocolName)) {
          throw new Error('Protocol names can only contain letters, numbers and spaces')
        }
        if (protocolName.endsWith(' protocol')) {
          throw new Error('No need to end your protocol name with " protocol"')
        }
        return `${securityLevel}-${protocolName}-${keyID}`
      }
      const invoiceNumber = computeInvoiceNumber(protocolID, keyID)
      const invoiceNumberBin = Utils.toArray(invoiceNumber, 'utf8')

      // Compute expected linkage
      const expectedLinkage = Hash.sha256hmac(sharedSecret, invoiceNumberBin)

      // Compare linkage and expectedLinkage
      expect(linkage).toEqual(expectedLinkage)

      await proverWallet.destroyKey()
      await verifierWallet.destroyKey()
    })
  })
  describe('PrivilegedKeyManager - Internal Logic Tests', () => {
    beforeEach(() => {
      jest.useFakeTimers()
    })
    afterEach(() => {
      jest.clearAllTimers()
      jest.useRealTimers()
    })
    it('Calls keyGetter only once if getPrivilegedKey is invoked multiple times within retention period', async () => {
      // Create a mock keyGetter that returns a PrivateKey
      const keyGetterMock = jest.fn(async (reason: string) => {
        return new PrivateKey(getRandom32ByteHex(), 'hex')
      })

      // Retention period is 100 ms for testing
      const km = new PrivilegedKeyManager(keyGetterMock, 100)

      // 1) First call, should call keyGetter once
      const key1 = await (km as any).getPrivilegedKey('first reason')
      expect(keyGetterMock).toHaveBeenCalledTimes(1)

      // 2) Second call, if within retention, should NOT call keyGetter again
      const key2 = await (km as any).getPrivilegedKey('second reason')
      expect(keyGetterMock).toHaveBeenCalledTimes(1)

      // 3) Check that both keys match the same underlying private key
      expect(key1.toHex()).toBe(key2.toHex())
      await km.destroyKey()
    })

    it('Destroys key after retention period elapses', async () => {
      const keyGetterMock = jest.fn(async (reason: string) => {
        return new PrivateKey(getRandom32ByteHex(), 'hex')
      })

      const retentionMs = 200
      const km = new PrivilegedKeyManager(keyGetterMock, retentionMs)

      // Acquire the key
      await (km as any).getPrivilegedKey('test reason')

      // We have chunkPropNames set
      expect((km as any).chunkPropNames.length).toBeGreaterThan(0)

      // Fast-forward time beyond the retention period
      jest.advanceTimersByTime(retentionMs + 1)

      // The destroyKey logic should have run
      expect((km as any).chunkPropNames.length).toBe(0)
      expect((km as any).chunkPadPropNames.length).toBe(0)
      expect((km as any).decoyPropNamesDestroy.length).toBe(0)
      await km.destroyKey()
    })

    it('Explicitly calls destroyKey() and removes all chunk properties', async () => {
      const keyGetterMock = jest.fn(async (reason: string) => {
        return new PrivateKey(getRandom32ByteHex(), 'hex')
      })
      const km = new PrivilegedKeyManager(keyGetterMock, 5000)

      // Acquire the key
      await (km as any).getPrivilegedKey('destroy test')

      // Verify chunk props exist
      expect((km as any).chunkPropNames.length).toBeGreaterThan(0)
      expect((km as any).chunkPadPropNames.length).toBeGreaterThan(0)

      // Explicitly call destroyKey
      ;(km as any).destroyKey()

      // Now chunkPropNames and chunkPadPropNames should be cleared
      expect((km as any).chunkPropNames.length).toBe(0)
      expect((km as any).chunkPadPropNames.length).toBe(0)
      await km.destroyKey()
    })

    it('Reuses in-memory obfuscated key if data is valid, otherwise fetches a new key', async () => {
      const mockHex = getRandom32ByteHex()
      const keyGetterMock = jest.fn(async () => new PrivateKey(mockHex, 'hex'))

      const km = new PrivilegedKeyManager(keyGetterMock, 5000)

      // 1) First retrieval => calls keyGetter
      const key1 = await (km as any).getPrivilegedKey('reuse test')
      expect(keyGetterMock).toHaveBeenCalledTimes(1)
      expect(key1.toHex()).toBe(mockHex)

      // 2) Tamper with chunk data so reassembleKeyFromChunks returns null
      // We can zero out one chunk or remove it
      ;(km as any)[(km as any).chunkPropNames[0]] = undefined

      // 3) Second retrieval => chunk data is invalid => calls keyGetter again
      const key2 = await (km as any).getPrivilegedKey('reuse test 2')
      expect(keyGetterMock).toHaveBeenCalledTimes(2)
      // The newly fetched key must still match mockHex,
      // because the mock always returns the same key.
      expect(key2.toHex()).toBe(mockHex)
      await km.destroyKey()
    })

    it('Ensures chunk-splitting logic is correct for a 32-byte key', async () => {
      const km = new PrivilegedKeyManager(async () => new PrivateKey(1), 5000)

      const testBytes = new Uint8Array(32)
      // Fill with some pattern, e.g. 0..31
      testBytes.forEach((_, i) => {
        testBytes[i] = i
      })

      const chunks = (km as any).splitKeyIntoChunks(testBytes)
      expect(chunks.length).toBe((km as any).CHUNK_COUNT)

      // By default CHUNK_COUNT = 4
      // Typically each chunk would be 8 bytes (for a 32-byte key).
      chunks.forEach((chunk: Uint8Array, i: number) => {
        if (i < 3) {
          expect(chunk.length).toBe(8)
        } else {
          // last chunk picks up leftover
          expect(chunk.length).toBe(8)
        }
      })

      // Reassemble logic typically is done by reassembleKeyFromChunks,
      // but let's test it in isolation. We'll XOR with random pads,
      // store them, reassemble, etc.

      // For demonstration, we can do a quick test:
      const pad = chunks.map((c: Uint8Array) => Uint8Array.from(Random(c.length)))
      const obfuscated = chunks.map((c: Uint8Array, i: number) => (km as any).xorBytes(c, pad[i]))

      // Then "store" and reassemble
      ;(km as any).chunkPropNames = []
      ;(km as any).chunkPadPropNames = []
      obfuscated.forEach((obf: Uint8Array, i: number) => {
        const chunkProp = `chunk${i}`
        const padProp = `pad${i}`
        ;(km as any).chunkPropNames.push(chunkProp)
        ;(km as any).chunkPadPropNames.push(padProp)
        ;(km as any)[chunkProp] = obf
        ;(km as any)[padProp] = pad[i]
      })
      const reassembled = (km as any).reassembleKeyFromChunks()
      expect(reassembled.length).toBe(32)
      expect(Array.from(reassembled)).toEqual(Array.from(testBytes))
      await km.destroyKey()
    })

    it('XOR function works as expected', async () => {
      const km = new PrivilegedKeyManager(async () => new PrivateKey(1), 5000)
      const a = Uint8Array.from([0, 1, 255])
      const b = Uint8Array.from([255, 1, 0])

      const result = (km as any).xorBytes(a, b)
      // 0 ^ 255 = 255, 1 ^ 1 = 0, 255 ^ 0 = 255
      expect(Array.from(result)).toEqual([255, 0, 255])

      // XOR with zero array => same array
      const zero = new Uint8Array(3)
      const result2 = (km as any).xorBytes(a, zero)
      expect(Array.from(result2)).toEqual([0, 1, 255])
      await km.destroyKey()
    })

    it('Generates random property names', async () => {
      const km = new PrivilegedKeyManager(async () => new PrivateKey(1), 5000)
      const prop1 = (km as any).generateRandomPropName()
      const prop2 = (km as any).generateRandomPropName()
      expect(prop1).not.toBe(prop2)
      // Just check format (roughly)
      expect(prop1).toMatch(/^_[0-9a-f]{8}_[0-9]{1,6}$/)
      expect(prop2).toMatch(/^_[0-9a-f]{8}_[0-9]{1,6}$/)
      await km.destroyKey()
    })

    it('Sets up initial decoy properties in the constructor', async () => {
      const km = new PrivilegedKeyManager(async () => new PrivateKey(1), 5000)
      // decoyPropNamesRemain has length 2
      expect((km as any).decoyPropNamesRemain.length).toBe(2)
      // Validate those properties actually exist on the object
      for (const propName of (km as any).decoyPropNamesRemain) {
        expect((km as any)[propName]).toBeInstanceOf(Uint8Array)
        expect((km as any)[propName].length).toBe(16)
      }
      await km.destroyKey()
    })

    it('New decoy properties are created on each key fetch and destroyed on destroy', async () => {
      const km = new PrivilegedKeyManager(async () => new PrivateKey(1), 5000)
      await (km as any).getPrivilegedKey('decoy test')

      // We should have 2 decoy props that remain, plus 2 that are "destroyable"
      expect((km as any).decoyPropNamesRemain.length).toBe(2)
      expect((km as any).decoyPropNamesDestroy.length).toBe(2)

      // Destroy them
      ;(km as any).destroyKey()
      expect((km as any).decoyPropNamesDestroy.length).toBe(0)
      await km.destroyKey()
    })
  })
})