var result = crypto
.subtle.unwrapKey(format, wrappedKey, unwrappingKey, unwrapAlgo, unwrappedKeyAlgo, extractable, keyUsages);
formatis an enumerated value describing the data format of the key to unwrap. 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.
ArrayBufferor a ... containing the wrapped key in the given format.
CryptoKeyto use to unwrap.
DOMStringrepresenting the algorithm used to perform the unwrapping. It is one of the following:
DOMStringrepresenting the algorithm of the wrapped key.
Booleanindicating if the key can be extracted from the
CryptoKeyobject at a later stage.
Arrayindicating what can be done with the unwrapped 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.
The promise is rejected when one of the following exceptions is encountered:
InvalidAccessErrorwhen the unwrapping key is not a key for the requested unwrap algorithm or if the
CryptoKey.usagesvalue of that key doesn't contain
NotSupportedwhen trying to use an algorithm that is either unknown or isn't suitable for encryption or wrapping.
keyUsagesis empty but the unwrapped key is of type
TypeErrorwhen trying to use an invalid format.
|Web Cryptography API
The definition of 'SubtleCrypto.unwrapKey()' in that specification.
|Feature||Android webview||Chrome for Android||Edge mobile||Firefox for Android||Opera Android||iOS Safari||Samsung Internet|
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1. From version 32 until version 34 (exclusive): this feature is behind the
dom.webcrypto.enabled preference (needs to be set to
true). To change preferences in Firefox, visit about:config.
KeyOperation instead of