SubtleCrypto

Secure context
This feature is available only in secure contexts (HTTPS), in some or all supporting browsers .

SubtleCrypto interface of the Web 加密 API provides a number of low-level cryptographic functions. Access to the features of SubtleCrypto is obtained through the subtle 特性为 Crypto object you get from Window.crypto .

警告: This API provides a number of low-level cryptographic primitives. It's very easy to misuse them, and the pitfalls involved can be very subtle.

Even assuming you use the basic cryptographic functions correctly, secure key management and overall security system design are extremely hard to get right, and are generally the domain of specialist security experts.

Errors in security system design and implementation can make the security of the system completely ineffective.

If you're not sure you know what you are doing, you probably shouldn't be using this API.

特性

This interface doesn't inherit any properties, as it has no parent interface.

方法

This interface doesn't inherit any methods, as it has no parent interface.

SubtleCrypto.encrypt()
返回 Promise that fufills with the encrypted data corresponding to the clear text, algorithm, and key given as parameters.
SubtleCrypto.decrypt()
返回 Promise that fulfills with the clear data corresponding to the encrypted text, algorithm, and key given as parameters.
SubtleCrypto.sign()
返回 Promise that fulfills with the signature corresponding to the text, algorithm, and key given as parameters.
SubtleCrypto.verify()
返回 Promise that fulfills with a Boolean value indicating if the signature given as a parameter matches the text, algorithm, and key that are also given as parameters.
SubtleCrypto.digest()
返回 Promise that fulfills with a digest generated from the algorithm and text given as parameters.
SubtleCrypto.generateKey()
返回 Promise that fulfills with a newly-generated CryptoKey , for symmetrical algorithms, or a CryptoKeyPair , containing two newly generated keys, for asymmetrical algorithms. These will match the algorithm, usages, and extractability given as parameters.
SubtleCrypto.deriveKey()
返回 Promise that fulfills with a newly generated CryptoKey derived from the master key and specific algorithm given as parameters.
SubtleCrypto.deriveBits()
返回 Promise that fulfills with a newly generated buffer of pseudo-random bits derived from the master key and specific algorithm given as parameters.
SubtleCrypto.importKey()
返回 Promise that fulfills with a CryptoKey corresponding to the format, the algorithm, raw key data, usages, and extractability given as parameters.
SubtleCrypto.exportKey()
返回 Promise that fulfills with a buffer containing the key in the requested format.
SubtleCrypto.wrapKey()
返回 Promise that fulfills with a wrapped symmetric key for usage (transfer and storage) in insecure environments. The wrapped key matches the format specified in the given parameters, and wrapping is done by the given wrapping key, using the specified algorithm.
SubtleCrypto.unwrapKey()
返回 Promise that fulfills with a CryptoKey corresponding to the wrapped key given in the parameter.

Using SubtleCrypto

We can split the functions implemented by this API into two groups: cryptography functions and key management functions.

Cryptography functions

These are the functions you can use to implement security features such as privacy and authentication in a system. The SubtleCrypto API provides the following cryptography functions:

* sign() and verify() : create and verify digital signatures.
* encrypt() and decrypt() : encrypt and decrypt data.
* digest() : create a fixed-length, collision-resistant digest of some data.

Key management functions

Except for digest() , all the cryptography functions in the API use cryptographic keys. In the SubtleCrypto API a cryptographic key is represented using a CryptoKey object. To perform operations like signing and encrypting, you pass a CryptoKey object into the sign() or encrypt() 函数。

Generating and deriving keys

generateKey() and deriveKey() functions both create a new CryptoKey 对象。

The difference is that generateKey() will generate a new distinct key value each time you call it, while deriveKey() derives a key from some initial keying material. If you provide the same keying material to two separate calls to deriveKey() , you will get two CryptoKey objects that have the same underlying value. This is useful if, for example, you want to derive an encryption key from a password and later derive the same key from the same password to decrypt the data.

Importing and exporting keys

To make keys available outside your app, you need to export the key, and that's what exportKey() is for. You can choose one of a number of export formats.

The inverse of exportKey() is importKey() . You can import keys from other systems, and support for standard formats like PKCS #8 and JSON Web Key helps you do this. The exportKey() function exports the key in an unencrypted format.

If the key is sensitive you should use wrapKey() , which exports the key and then encrypts it using another key; the API calls a "key-wrapping key".

The inverse of wrapKey() is unwrapKey() , which decrypts then imports the key.

Storing keys

CryptoKey objects can be stored using the structured clone algorithm , meaning that you can store and retrieve them using standard web storage APIs. The specification expects that most developers will use the IndexedDB API to store CryptoKey 对象。

Supported algorithms

The cryptographic functions provided by the Web Crypto API can be performed by one or more different cryptographic algorithms : the algorithm argument to the function indicates which algorithm to use. Some algorithms need extra parameters: in these cases the algorithm argument is a dictionary object that includes the extra parameters.

The table below summarises which algorithms are suitable for which cryptographic operations:

sign()

verify()

encrypt()

decrypt()

digest()

deriveBits()

deriveKey()

wrapKey()

unwrapKey()

RSASSA-PKCS1-v1_5
RSA-PSS
ECDSA
HMAC
RSA-OAEP
AES-CTR
AES-CBC
AES-GCM
SHA-1
SHA-256
SHA-384
SHA-512
ECDH
HKDF
PBKDF2
AES-KW

规范

规范 状态 Comment
Web Cryptography API
The definition of 'SubtleCrypto' in that specification.
Recommendation 初始定义。

浏览器兼容性

更新 GitHub 上的兼容性数据
Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
SubtleCrypto Chrome 37 Edge 部分支持 12 Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11 Opera 24 Safari 10.1
10.1
7
Prefixed
Prefixed Implemented with the vendor prefix: WebKit
WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 10.3
10.3
7
Prefixed
Prefixed Implemented with the vendor prefix: WebKit
Samsung Internet Android 6.0
decrypt Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: AES-CTR.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 CryptoOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
deriveBits Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: ECDH.
Not supported: HKDF, PBKDF2.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE No Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
deriveKey Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: ECDH.
Not supported: HKDF, PBKDF2.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE No Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
digest Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: SHA-1.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 CryptoOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
encrypt Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: AES-CTR.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 CryptoOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
exportKey Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: RSA-PSS, ECDSA, ECDH.
Not supported: AES-CTR.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 KeyOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
generateKey Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: RSA-PSS, ECDSA, ECDH.
Not supported: AES-CTR.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 KeyOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
importKey Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: RSA-PSS, ECDSA, ECDH.
Not supported: AES-CTR, HKDF, PBKDF2.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 KeyOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
Secure context required Chrome 60 Edge 79 Firefox 75 IE No Opera 47 Safari No WebView Android 60 Chrome Android 60 Firefox Android No Opera Android 47 Safari iOS No Samsung Internet Android No
sign Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: RSA-PSS, ECDSA.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 CryptoOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
unwrapKey Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: AES-CTR.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 KeyOperation instead of Promise
Opera 24 Safari 7 WebView Android ? Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
verify Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: RSA-PSS, ECDSA.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 CryptoOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0
Available in workers Chrome ? Edge ? Firefox 48 IE ? Opera ? Safari ? WebView Android ? Chrome Android ? Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android ?
wrapKey Chrome 37 Edge 部分支持 12
部分支持 12
Not supported: AES-CTR.
Firefox 34
34
不支持 32 — 34
Disabled
Disabled 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.
IE 部分支持 11
部分支持 11
返回 KeyOperation instead of Promise
Opera 24 Safari 7 WebView Android 37 Chrome Android 37 Firefox Android 34
34
不支持 32 — 34
Disabled
Disabled 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.
Opera Android 24 Safari iOS 7 Samsung Internet Android 6.0

图例

完整支持
完整支持
部分支持
部分支持
不支持
不支持
兼容性未知
兼容性未知
见实现注意事项。
用户必须明确启用此特征。
用户必须明确启用此特征。
要求使用供应商前缀或不同名称。
要求使用供应商前缀或不同名称。

另请参阅