SubtleCrypto.wrapKey

The SubtleCrypto.wrapKey() method returns a Promise of a wrapped symmetric key for usage (transfer, storage) in unsecure environments. The wrapped buffer returned is in the format given in parameters, and contained the key wrapped by the give wrapping key with the given algorithm.

Syntax

var result = crypto.wrapKey(format, key, wrappingKey, wrapAlgo);

Parameters

• format is an enumerated value describing the data format in which the key must be wrapped. It can be one of the following:
  • "raw", the key as an array of bytes, usually a secret key.
  • "pkcs8" a private key, in the IETF Public Key-Cryptographic Standard Encryption #8.
  • "spki", usually a public key, in the Simple public key infrastructure standard
  • "jwk", the key in the JSON Web Key format.
• key is the CryptoKey to wrap.
• wrappingkey is the CryptoKey used to perform the wrapping.
• wrapAlgo is the DOMString} representing the algorithm used to perform the wrapping. It is one of the following: AES-CBC, AES-CTR, AES-GCM, RSA-OAEP, and AES-KW.

Return value

• result is a Promise that returns the wrapped key in the requested format.

Exceptions

The promise is rejected when one of the following exceptions is encountered:

• InvalidAccessError when the wrapping key is not a key for the requested wrap algorithm.
• NotSupported when trying to use an algorithm that is either unknown or isn't suitable for encryption or wrapping.
• TypeError when trying to use an invalid format.

Specifications

Specification	Status	Comment
Web Cryptography API The definition of 'SubtleCrypto.wrapKey()' in that specification.	Candidate Recommendation	Initial definition.

Browser compatibility

See also

• Crypto and Crypto.subtle.
• SubtleCrypto, the interface it belongs to.