wrapKey method

JSPromise<JSAny?> wrapKey(
  1. KeyFormat format,
  2. CryptoKey key,
  3. CryptoKey wrappingKey,
  4. AlgorithmIdentifier wrapAlgorithm,
)

The wrapKey() method of the SubtleCrypto interface "wraps" a key. This means that it exports the key in an external, portable format, then encrypts the exported key. Wrapping a key helps protect it in untrusted environments, such as inside an otherwise unprotected data store or in transmission over an unprotected network.

As with SubtleCrypto.exportKey, you specify an export format for the key. To export a key, it must have CryptoKey.extractable set to true.

But because wrapKey() also encrypts the key to be exported, you also need to pass in the key that must be used to encrypt it. This is sometimes called the "wrapping key".

The inverse of wrapKey() is SubtleCrypto.unwrapKey: while wrapKey is composed of export + encrypt, unwrapKey is composed of import + decrypt.

Implementation

external JSPromise<JSAny?> wrapKey(
  KeyFormat format,
  CryptoKey key,
  CryptoKey wrappingKey,
  AlgorithmIdentifier wrapAlgorithm,
);