subtle.deriveKey(algorithm, baseKey, derivedKeyAlgorithm, extractable, keyUsages)

• algorithm：<AlgorithmIdentifier> | <EcdhKeyDeriveParams> | <HkdfParams> | <Pbkdf2Params>

• baseKey：<CryptoKey>

• derivedKeyAlgorithm：<HmacKeyGenParams> | <AesKeyGenParams>

• extractable：<boolean>

• keyUsages：<string[]> 参见 关键用法。

  ¥keyUsages: <string[]> See Key usages.

• 返回：<Promise> 包含 <CryptoKey>

  ¥Returns: <Promise> containing <CryptoKey>

使用 algorithm 中指定的方法和参数，以及 baseKey 提供的密钥材料，subtle.deriveKey() 尝试基于 derivedKeyAlgorithm 中的方法和参数生成新的 <CryptoKey>。

¥Using the method and parameters specified in algorithm, and the keying material provided by baseKey, subtle.deriveKey() attempts to generate a new <CryptoKey> based on the method and parameters in derivedKeyAlgorithm.

调用 subtle.deriveKey() 相当于调用 subtle.deriveBits() 生成原始密钥材料，然后使用 deriveKeyAlgorithm、extractable 和 keyUsages 参数作为输入将结果传递到 subtle.importKey() 方法。

¥Calling subtle.deriveKey() is equivalent to calling subtle.deriveBits() to generate raw keying material, then passing the result into the subtle.importKey() method using the deriveKeyAlgorithm, extractable, and keyUsages parameters as input.

目前支持的算法包括：

¥The algorithms currently supported include:

• 'ECDH'

• 'HKDF'

• 'PBKDF2'