SubtleCrypto.importKey

The SubtleCrypto.importKey() method returns a Promise of the CryptoKey generated from the data given in parameters.

Syntax

var result = crypto.importKey(format, keyData, algo, extractable, usages);

Parameters

• format is an enumerated value describing the data format of the key to imported. 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.
• keyData is an ArrayBuffer or a JSONWebKey containing the key in the given format.
• algo is a DOMString defining the signature function to use. Supported values are: AES-CTR, AES-CBC, AES-GCM, RSA-OAEP, AES-KW, HMAC, RSASSA-PKCS1-v1_5, ECDSA, ECDH, DH.
• extractable is a Boolean indicating if the key can be extracted from the CryptoKey object at a later stage.
• usages is an Array indicating what can be done with the key. Possible values of the array are:
  • "encrypt", allowing the key to be used for encrypting messages.
  • "decrypt", allowing the key to be used for decrypting messages.
  • "sign", allowing the key to be used for signing messages.
  • "verify", allowing the key to be used for verifying the signature of messages.
  • "deriveKey", allowing the key to be used as a base key when deriving a new key.
  • "deriveBits", allowing the key to be used as a base key when deriving bits of data for use in cryptographic primitives.
  • "wrapKey", allowing the key to wrap a symmetric key for usage (transfer, storage) in unsecure environments.
  • "unwrapKey", allowing the key to unwrap a symmetric key for usage (transfer, storage) in unsecure environments.

Return value

• result is a Promise that returns the generated CryptoKey.

Exceptions

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

• SyntaxError when keyUsages is empty but the unwrapped key is of type "secret" or "private".
• TypeError when trying to use an invalid format or if the keyData is not suited for that format.

Specifications

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

Browser compatibility

See also

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