Node.js v8.9.0 文档


目录

crypto (加密)#

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稳定性: 2 - 稳定的

crypto 模块提供了加密功能,包含对 OpenSSL 的哈希、HMAC、加密、解密、签名、以及验证功能的一整套封装。

使用 require('crypto') 来访问该模块。

const crypto = require('crypto');

const secret = 'abcdefg';
const hash = crypto.createHmac('sha256', secret)
                   .update('I love cupcakes')
                   .digest('hex');
console.log(hash);
// Prints:
//   c0fa1bc00531bd78ef38c628449c5102aeabd49b5dc3a2a516ea6ea959d6658e

Determining if crypto support is unavailable#

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可以在不包括支持 crypto 模块的情况下构建 Node.js, 这时, 调用 require('crypto') 将 导致抛出异常.

let crypto;
try {
  crypto = require('crypto');
} catch (err) {
  console.log('不支持 crypto!');
}

Class: Certificate#

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SPKAC 最初是由 Netscape 实现的一种证书签名请求机制, 现在正式成为 HTML5's keygen element 的一部分.

crypto 模块提供 Certificate 类用于处理 SPKAC 数据. 最普遍的用法是处理 HTML5 keygen 元素 产生的输出. Node.js 内部使用 OpenSSL's SPKAC implementation 处理.

new crypto.Certificate()#

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可以使用 new 关键字或者调用 crypto.Certificate() 方法创建 Certificate 类的实例:

const crypto = require('crypto');

const cert1 = new crypto.Certificate();
const cert2 = crypto.Certificate();

certificate.exportChallenge(spkac)#

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const cert = require('crypto').Certificate();
const spkac = getSpkacSomehow();
const challenge = cert.exportChallenge(spkac);
console.log(challenge.toString('utf8'));
// Prints: the challenge as a UTF8 string

certificate.exportPublicKey(spkac)#

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const cert = require('crypto').Certificate();
const spkac = getSpkacSomehow();
const publicKey = cert.exportPublicKey(spkac);
console.log(publicKey);
// Prints: the public key as <Buffer ...>

certificate.verifySpkac(spkac)#

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const cert = require('crypto').Certificate();
const spkac = getSpkacSomehow();
console.log(cert.verifySpkac(Buffer.from(spkac)));
// Prints: true 或者 false

Class: Cipher#

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Cipher类的实例用于加密数据。这个类可以用在以下两种方法中的一种:

  • 作为stream,既可读又可写,未加密数据的编写是为了在可读的方面生成加密的数据,或者
  • 使用cipher.update()cipher.final()方法产生加密的数据。

crypto.createCipher()crypto.createCipheriv()方法用于创建Cipher实例。Cipher对象不能直接使用new关键字创建。

示例:使用Cipher对象作为流:

const crypto = require('crypto');
const cipher = crypto.createCipher('aes192', 'a password');

let encrypted = '';
cipher.on('readable', () => {
  const data = cipher.read();
  if (data)
    encrypted += data.toString('hex');
});
cipher.on('end', () => {
  console.log(encrypted);
  // Prints: ca981be48e90867604588e75d04feabb63cc007a8f8ad89b10616ed84d815504
});

cipher.write('some clear text data');
cipher.end();

示例:使用Cipher和管道流:

const crypto = require('crypto');
const fs = require('fs');
const cipher = crypto.createCipher('aes192', 'a password');

const input = fs.createReadStream('test.js');
const output = fs.createWriteStream('test.enc');

input.pipe(cipher).pipe(output);

示例:使用cipher.update()cipher.final()方法:

const crypto = require('crypto');
const cipher = crypto.createCipher('aes192', 'a password');

let encrypted = cipher.update('some clear text data', 'utf8', 'hex');
encrypted += cipher.final('hex');
console.log(encrypted);
// Prints: ca981be48e90867604588e75d04feabb63cc007a8f8ad89b10616ed84d815504

cipher.final([outputEncoding])#

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返回任何未加密的内容。如果 outputEncoding 参数是'latin1', 'base64' 或者 'hex',返回字符串。 如果没有提供 outputEncoding,则返回Buffer

一旦cipher.final()方法已被调用,Cipher 对象就不能再用于加密数据。如果试图再次调用cipher.final(),将会抛出一个错误。

cipher.setAAD(buffer)#

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  • buffer <Buffer>
  • 返回<Cipher>方法链。

当使用经过验证的加密模式(目前只支持GCM)时,cipher.setAAD()方法设置用于additional authenticated data(附加验证的data(AAD))输入参数的值。

cipher.setAAD()法必须在cipher.update()之前调用。

cipher.getAuthTag()#

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当使用经验证的加密模式时(目前只有GCM支持),cipher.getAuthTag()方法返回一个Buffer,此Buffer包含已从给定数据计算后的authentication tagcipher.getAuthTag()方法只能在使用cipher.final()方法完全加密后调用。

cipher.setAutoPadding([autoPadding])#

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  • autoPadding <boolean> 默认为 true.
  • 返回<Cipher>方法链。

当使用块加密算法时,Cipher类会自动添加padding到输入数据中,来适配相应块大小。可调用cipher.setAutoPadding(false)禁用默认padding。

autoPaddingfalse时,整个输入数据的长度必须是cipher块大小的倍数,否则cipher.final()将抛出一个错误。 禁用自动填充对于非标准填充是有用的,例如使用0x0代替PKCS填充。

cipher.setAutoPadding()必须在cipher.final()之前被调用。

cipher.update(data[, inputEncoding][, outputEncoding])#

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data更新密码。如果给出了inputEncoding的论证,它的值必须是'utf8', 'ascii', 或者'latin1',而data参数是使用指定编码的字符串。如果不给出inputEncoding的参数,则data必须是BufferTypedArray, 或者DataView。如果data是一个BufferTypedArray, 或者 DataView, 那么inputEncoding就被忽略了。

outputEncoding指定了加密数据的输出格式,可以是'latin1''base64' 或者 'hex'。如果指定了outputEncoding,则返回使用指定编码的字符串。如果没有outputEncoding被提供,会返回Buffer

cipher.update()方法可以用新数据多次调用,直到cipher.final()被调用。 [' cipher.final()'][]。在cipher.final()之后调用cipher.update()将抛出错误。

Class: Decipher#

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Decipher类的实例用于解密数据。这个类可以用在以下两种方法中的一种:

crypto.createDecipher()crypto.createDecipheriv()的方法 用于创建Decipher实例。Decipher对象不能直接使用new关键字创建。

示例:使用Decipher对象作为流:

const crypto = require('crypto');
const decipher = crypto.createDecipher('aes192', 'a password');

let decrypted = '';
decipher.on('readable', () => {
  const data = decipher.read();
  if (data)
    decrypted += data.toString('utf8');
});
decipher.on('end', () => {
  console.log(decrypted);
  // Prints: some clear text data
});

const encrypted =
    'ca981be48e90867604588e75d04feabb63cc007a8f8ad89b10616ed84d815504';
decipher.write(encrypted, 'hex');
decipher.end();

示例:使用Decipher和管道流:

const crypto = require('crypto');
const fs = require('fs');
const decipher = crypto.createDecipher('aes192', 'a password');

const input = fs.createReadStream('test.enc');
const output = fs.createWriteStream('test.js');

input.pipe(decipher).pipe(output);

示例:使用decipher.update()decipher.final()方法:

const crypto = require('crypto');
const decipher = crypto.createDecipher('aes192', 'a password');

const encrypted =
    'ca981be48e90867604588e75d04feabb63cc007a8f8ad89b10616ed84d815504';
let decrypted = decipher.update(encrypted, 'hex', 'utf8');
decrypted += decipher.final('utf8');
console.log(decrypted);
// Prints: some clear text data

decipher.final([outputEncoding])#

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Returns any remaining deciphered contents. If outputEncoding parameter is one of 'latin1', 'ascii' or 'utf8', a string is returned. If an outputEncoding is not provided, a Buffer is returned.

Once the decipher.final() method has been called, the Decipher object can no longer be used to decrypt data. Attempts to call decipher.final() more than once will result in an error being thrown.

decipher.setAAD(buffer)#

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When using an authenticated encryption mode (only GCM is currently supported), the decipher.setAAD() method sets the value used for the additional authenticated data (AAD) input parameter.

The decipher.setAAD() method must be called before decipher.update().

decipher.setAuthTag(buffer)#

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When using an authenticated encryption mode (only GCM is currently supported), the decipher.setAuthTag() method is used to pass in the received authentication tag. If no tag is provided, or if the cipher text has been tampered with, decipher.final() with throw, indicating that the cipher text should be discarded due to failed authentication.

The decipher.setAuthTag() method must be called before decipher.final().

decipher.setAutoPadding([autoPadding])#

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  • autoPadding <boolean> Defaults to true.
  • Returns the <Cipher> for method chaining.

When data has been encrypted without standard block padding, calling decipher.setAutoPadding(false) will disable automatic padding to prevent decipher.final() from checking for and removing padding.

Turning auto padding off will only work if the input data's length is a multiple of the ciphers block size.

The decipher.setAutoPadding() method must be called before decipher.final().

decipher.update(data[, inputEncoding][, outputEncoding])#

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Updates the decipher with data. If the inputEncoding argument is given, its value must be one of 'latin1', 'base64', or 'hex' and the data argument is a string using the specified encoding. If the inputEncoding argument is not given, data must be a Buffer. If data is a Buffer then inputEncoding is ignored.

The outputEncoding specifies the output format of the enciphered data, and can be 'latin1', 'ascii' or 'utf8'. If the outputEncoding is specified, a string using the specified encoding is returned. If no outputEncoding is provided, a Buffer is returned.

The decipher.update() method can be called multiple times with new data until decipher.final() is called. Calling decipher.update() after decipher.final() will result in an error being thrown.

Class: DiffieHellman#

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DiffieHellman类是一个用来创建Diffie-Hellman键交换的工具。 DiffieHellman类的实例可以使用crypto.createDiffieHellman()方法。

const crypto = require('crypto');
const assert = require('assert');

// Generate Alice's keys...
const alice = crypto.createDiffieHellman(2048);
const aliceKey = alice.generateKeys();

// Generate Bob's keys...
const bob = crypto.createDiffieHellman(alice.getPrime(), alice.getGenerator());
const bobKey = bob.generateKeys();

// Exchange and generate the secret...
const aliceSecret = alice.computeSecret(bobKey);
const bobSecret = bob.computeSecret(aliceKey);

// OK
assert.strictEqual(aliceSecret.toString('hex'), bobSecret.toString('hex'));

diffieHellman.computeSecret(otherPublicKey[, inputEncoding][, outputEncoding])#

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Computes the shared secret using otherPublicKey as the other party's public key and returns the computed shared secret. The supplied key is interpreted using the specified inputEncoding, and secret is encoded using specified outputEncoding. Encodings can be 'latin1', 'hex', or 'base64'. If the inputEncoding is not provided, otherPublicKey is expected to be a Buffer, TypedArray, or DataView.

If outputEncoding is given a string is returned; otherwise, a Buffer is returned.

diffieHellman.generateKeys([encoding])#

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Generates private and public Diffie-Hellman key values, and returns the public key in the specified encoding. This key should be transferred to the other party. Encoding can be 'latin1', 'hex', or 'base64'. If encoding is provided a string is returned; otherwise a Buffer is returned.

diffieHellman.getGenerator([encoding])#

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Returns the Diffie-Hellman generator in the specified encoding, which can be 'latin1', 'hex', or 'base64'. If encoding is provided a string is returned; otherwise a Buffer is returned.

diffieHellman.getPrime([encoding])#

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Returns the Diffie-Hellman prime in the specified encoding, which can be 'latin1', 'hex', or 'base64'. If encoding is provided a string is returned; otherwise a Buffer is returned.

diffieHellman.getPrivateKey([encoding])#

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Returns the Diffie-Hellman private key in the specified encoding, which can be 'latin1', 'hex', or 'base64'. If encoding is provided a string is returned; otherwise a Buffer is returned.

diffieHellman.getPublicKey([encoding])#

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Returns the Diffie-Hellman public key in the specified encoding, which can be 'latin1', 'hex', or 'base64'. If encoding is provided a string is returned; otherwise a Buffer is returned.

diffieHellman.setPrivateKey(privateKey[, encoding])#

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Sets the Diffie-Hellman private key. If the encoding argument is provided and is either 'latin1', 'hex', or 'base64', privateKey is expected to be a string. If no encoding is provided, privateKey is expected to be a Buffer, TypedArray, or DataView.

diffieHellman.setPublicKey(publicKey[, encoding])#

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Sets the Diffie-Hellman public key. If the encoding argument is provided and is either 'latin1', 'hex' or 'base64', publicKey is expected to be a string. If no encoding is provided, publicKey is expected to be a Buffer, TypedArray, or DataView.

diffieHellman.verifyError#

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A bit field containing any warnings and/or errors resulting from a check performed during initialization of the DiffieHellman object.

The following values are valid for this property (as defined in constants module):

  • DH_CHECK_P_NOT_SAFE_PRIME
  • DH_CHECK_P_NOT_PRIME
  • DH_UNABLE_TO_CHECK_GENERATOR
  • DH_NOT_SUITABLE_GENERATOR

Class: ECDH#

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ECDH类是创建椭圆曲线Diffie-Hellman(Elliptic Curve Diffie-Hellman (ECDH))键交换的实用工具。 ECDH类的实例可以使用crypto.createECDH()方法。

const crypto = require('crypto');
const assert = require('assert');

// Generate Alice's keys...
const alice = crypto.createECDH('secp521r1');
const aliceKey = alice.generateKeys();

// Generate Bob's keys...
const bob = crypto.createECDH('secp521r1');
const bobKey = bob.generateKeys();

// Exchange and generate the secret...
const aliceSecret = alice.computeSecret(bobKey);
const bobSecret = bob.computeSecret(aliceKey);

assert.strictEqual(aliceSecret.toString('hex'), bobSecret.toString('hex'));
// OK

ecdh.computeSecret(otherPublicKey[, inputEncoding][, outputEncoding])#

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Computes the shared secret using otherPublicKey as the other party's public key and returns the computed shared secret. The supplied key is interpreted using specified inputEncoding, and the returned secret is encoded using the specified outputEncoding. Encodings can be 'latin1', 'hex', or 'base64'. If the inputEncoding is not provided, otherPublicKey is expected to be a Buffer, TypedArray, or DataView.

If outputEncoding is given a string will be returned; otherwise a Buffer is returned.

ecdh.generateKeys([encoding[, format]])#

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Generates private and public EC Diffie-Hellman key values, and returns the public key in the specified format and encoding. This key should be transferred to the other party.

The format argument specifies point encoding and can be 'compressed' or 'uncompressed'. If format is not specified, the point will be returned in 'uncompressed' format.

The encoding argument can be 'latin1', 'hex', or 'base64'. If encoding is provided a string is returned; otherwise a Buffer is returned.

ecdh.getPrivateKey([encoding])#

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Returns the EC Diffie-Hellman private key in the specified encoding, which can be 'latin1', 'hex', or 'base64'. If encoding is provided a string is returned; otherwise a Buffer is returned.

ecdh.getPublicKey([encoding][, format])#

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Returns the EC Diffie-Hellman public key in the specified encoding and format.

The format argument specifies point encoding and can be 'compressed' or 'uncompressed'. If format is not specified the point will be returned in 'uncompressed' format.

The encoding argument can be 'latin1', 'hex', or 'base64'. If encoding is specified, a string is returned; otherwise a Buffer is returned.

ecdh.setPrivateKey(privateKey[, encoding])#

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Sets the EC Diffie-Hellman private key. The encoding can be 'latin1', 'hex' or 'base64'. If encoding is provided, privateKey is expected to be a string; otherwise privateKey is expected to be a Buffer, TypedArray, or DataView.

If privateKey is not valid for the curve specified when the ECDH object was created, an error is thrown. Upon setting the private key, the associated public point (key) is also generated and set in the ECDH object.

ecdh.setPublicKey(publicKey[, encoding])#

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Stability: 0 - Deprecated

Sets the EC Diffie-Hellman public key. Key encoding can be 'latin1', 'hex' or 'base64'. If encoding is provided publicKey is expected to be a string; otherwise a Buffer, TypedArray, or DataView is expected.

Note that there is not normally a reason to call this method because ECDH only requires a private key and the other party's public key to compute the shared secret. Typically either ecdh.generateKeys() or ecdh.setPrivateKey() will be called. The ecdh.setPrivateKey() method attempts to generate the public point/key associated with the private key being set.

Example (obtaining a shared secret):

const crypto = require('crypto');
const alice = crypto.createECDH('secp256k1');
const bob = crypto.createECDH('secp256k1');

// Note: This is a shortcut way to specify one of Alice's previous private
// keys. It would be unwise to use such a predictable private key in a real
// application.
alice.setPrivateKey(
  crypto.createHash('sha256').update('alice', 'utf8').digest()
);

// Bob uses a newly generated cryptographically strong
// pseudorandom key pair
bob.generateKeys();

const aliceSecret = alice.computeSecret(bob.getPublicKey(), null, 'hex');
const bobSecret = bob.computeSecret(alice.getPublicKey(), null, 'hex');

// aliceSecret and bobSecret should be the same shared secret value
console.log(aliceSecret === bobSecret);

Class: Hash#

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Hash类是用于创建数据哈希值的工具类。它能用以下方法使用:

  • 作为一个stream,它既可读又可写,数据被写入要在可读的方面生成一个计算散列摘要

  • 使用hash.update()hash.digest()方法产生计算后的哈希。

crypto.createHash()方法用于创建Hash实例。Hash不能直接使用new关键字创建对象。

示例: 使用Hash对象作为流:

const crypto = require('crypto');
const hash = crypto.createHash('sha256');

hash.on('readable', () => {
  const data = hash.read();
  if (data) {
    console.log(data.toString('hex'));
    // Prints:
    //   6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50
  }
});

hash.write('some data to hash');
hash.end();

示例:使用 Hash 和管道流

const crypto = require('crypto');
const fs = require('fs');
const hash = crypto.createHash('sha256');

const input = fs.createReadStream('test.js');
input.pipe(hash).pipe(process.stdout);

示例:使用hash.update()hash.digest()

const crypto = require('crypto');
const hash = crypto.createHash('sha256');

hash.update('some data to hash');
console.log(hash.digest('hex'));
// Prints:
//   6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50

hash.digest([encoding])#

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Calculates the digest of all of the data passed to be hashed (using the hash.update() method). The encoding can be 'hex', 'latin1' or 'base64'. If encoding is provided a string will be returned; otherwise a Buffer is returned.

The Hash object can not be used again after hash.digest() method has been called. Multiple calls will cause an error to be thrown.

hash.update(data[, inputEncoding])#

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Updates the hash content with the given data, the encoding of which is given in inputEncoding and can be 'utf8', 'ascii' or 'latin1'. If encoding is not provided, and the data is a string, an encoding of 'utf8' is enforced. If data is a Buffer, TypedArray, or DataView, then inputEncoding is ignored.

This can be called many times with new data as it is streamed.

Class: Hmac#

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Hmac类是用于创建加密Hmac摘要的工具。它可以有两种用法:

  • 作为stream,它既可读又可写,数据被写入要在可读的方面生成一个经过计算的HMAC摘要。
  • 使用hmac.update()hmac.digest()方法产生计算后的HMAC摘要。

crypto.createHmac()方法用来创建Hmac实例。Hmac不能直接使用new关键字创建对象。

示例:使用Hmac对象作为流:

const crypto = require('crypto');
const hmac = crypto.createHmac('sha256', 'a secret');

hmac.on('readable', () => {
  const data = hmac.read();
  if (data) {
    console.log(data.toString('hex'));
    // Prints:
    //   7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e
  }
});

hmac.write('some data to hash');
hmac.end();

示例:使用Hmac和管道流

const crypto = require('crypto');
const fs = require('fs');
const hmac = crypto.createHmac('sha256', 'a secret');

const input = fs.createReadStream('test.js');
input.pipe(hmac).pipe(process.stdout);

示例:使用hmac.update()hmac.digest()方法

const crypto = require('crypto');
const hmac = crypto.createHmac('sha256', 'a secret');

hmac.update('some data to hash');
console.log(hmac.digest('hex'));
// Prints:
//   7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e

hmac.digest([encoding])#

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Calculates the HMAC digest of all of the data passed using hmac.update(). The encoding can be 'hex', 'latin1' or 'base64'. If encoding is provided a string is returned; otherwise a Buffer is returned;

The Hmac object can not be used again after hmac.digest() has been called. Multiple calls to hmac.digest() will result in an error being thrown.

hmac.update(data[, inputEncoding])#

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Updates the Hmac content with the given data, the encoding of which is given in inputEncoding and can be 'utf8', 'ascii' or 'latin1'. If encoding is not provided, and the data is a string, an encoding of 'utf8' is enforced. If data is a Buffer, TypedArray, or DataView, then inputEncoding is ignored.

This can be called many times with new data as it is streamed.

Class: Sign#

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“Sign”类是生成签名的实用工具。它有两种使用方式:

crypto.createSign()方法用于创建Sign实例。Sign实例不能直接使用new关键字创建。

示例:使用“符号”对象作为流:

const crypto = require('crypto');
const sign = crypto.createSign('SHA256');

sign.write('some data to sign');
sign.end();

const privateKey = getPrivateKeySomehow();
console.log(sign.sign(privateKey, 'hex'));
// Prints: the calculated signature using the specified private key and
// SHA-256. For RSA keys, the algorithm is RSASSA-PKCS1-v1_5 (see padding
// parameter below for RSASSA-PSS). For EC keys, the algorithm is ECDSA.

示例:使用sign.update()sign.sign()方法:

const crypto = require('crypto');
const sign = crypto.createSign('SHA256');

sign.update('some data to sign');

const privateKey = getPrivateKeySomehow();
console.log(sign.sign(privateKey, 'hex'));
// Prints: the calculated signature

一个Sign实例也可以通过仅仅通过摘要来创建算法名称,在这种情况下,OpenSSL将会从PEM-formatted私钥的类型推断出完整的签名算法,包括不直接暴露姓名常数的算法。比如'ecdsa-with-SHA256'。

示例:使用ECDSA与SHA256进行签名

const crypto = require('crypto');
const sign = crypto.createSign('RSA-SHA256');

sign.update('some data to sign');

const privateKey = getPrivateKeySomehow();
console.log(sign.sign(privateKey, 'hex'));
// Prints: the calculated signature

sign.sign(privateKey[, outputFormat])#

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Calculates the signature on all the data passed through using either sign.update() or sign.write().

The privateKey argument can be an object or a string. If privateKey is a string, it is treated as a raw key with no passphrase. If privateKey is an object, it must contain one or more of the following properties:

  • key: <string> - PEM encoded private key (required)
  • passphrase: <string> - passphrase for the private key
  • padding: <integer> - Optional padding value for RSA, one of the following:

    • crypto.constants.RSA_PKCS1_PADDING (default)
    • crypto.constants.RSA_PKCS1_PSS_PADDING

    Note that RSA_PKCS1_PSS_PADDING will use MGF1 with the same hash function used to sign the message as specified in section 3.1 of RFC 4055.

  • saltLength: <integer> - salt length for when padding is RSA_PKCS1_PSS_PADDING. The special value crypto.constants.RSA_PSS_SALTLEN_DIGEST sets the salt length to the digest size, crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN (default) sets it to the maximum permissible value.

The outputFormat can specify one of 'latin1', 'hex' or 'base64'. If outputFormat is provided a string is returned; otherwise a Buffer is returned.

The Sign object can not be again used after sign.sign() method has been called. Multiple calls to sign.sign() will result in an error being thrown.

sign.update(data[, inputEncoding])#

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Updates the Sign content with the given data, the encoding of which is given in inputEncoding and can be 'utf8', 'ascii' or 'latin1'. If encoding is not provided, and the data is a string, an encoding of 'utf8' is enforced. If data is a Buffer, TypedArray, or DataView, then inputEncoding is ignored.

This can be called many times with new data as it is streamed.

Class: Verify#

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Verify类是验证签名的工具。它可以两种方式使用:

crypto.createVerify()方法用于创建Verify实例。 Verify对象不能直接使用new关键字创建。

示例:使用“验证”对象作为流:

const crypto = require('crypto');
const verify = crypto.createVerify('SHA256');

verify.write('some data to sign');
verify.end();

const publicKey = getPublicKeySomehow();
const signature = getSignatureToVerify();
console.log(verify.verify(publicKey, signature));
// Prints: true or false

示例:使用verify.update()verify.verify()方法

const crypto = require('crypto');
const verify = crypto.createVerify('SHA256');

verify.update('some data to sign');

const publicKey = getPublicKeySomehow();
const signature = getSignatureToVerify();
console.log(verify.verify(publicKey, signature));
// Prints: true or false

verify.update(data[, inputEncoding])#

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Updates the Verify content with the given data, the encoding of which is given in inputEncoding and can be 'utf8', 'ascii' or 'latin1'. If encoding is not provided, and the data is a string, an encoding of 'utf8' is enforced. If data is a Buffer, TypedArray, or DataView, then inputEncoding is ignored.

This can be called many times with new data as it is streamed.

verify.verify(object, signature[, signatureFormat])#

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Verifies the provided data using the given object and signature. The object argument can be either a string containing a PEM encoded object, which can be an RSA public key, a DSA public key, or an X.509 certificate, or an object with one or more of the following properties:

  • key: <string> - PEM encoded public key (required)
  • padding: <integer> - Optional padding value for RSA, one of the following:

    • crypto.constants.RSA_PKCS1_PADDING (default)
    • crypto.constants.RSA_PKCS1_PSS_PADDING

    Note that RSA_PKCS1_PSS_PADDING will use MGF1 with the same hash function used to verify the message as specified in section 3.1 of RFC 4055.

  • saltLength: <integer> - salt length for when padding is RSA_PKCS1_PSS_PADDING. The special value crypto.constants.RSA_PSS_SALTLEN_DIGEST sets the salt length to the digest size, crypto.constants.RSA_PSS_SALTLEN_AUTO (default) causes it to be determined automatically.

The signature argument is the previously calculated signature for the data, in the signatureFormat which can be 'latin1', 'hex' or 'base64'. If a signatureFormat is specified, the signature is expected to be a string; otherwise signature is expected to be a Buffer, TypedArray, or DataView.

Returns true or false depending on the validity of the signature for the data and public key.

The verify object can not be used again after verify.verify() has been called. Multiple calls to verify.verify() will result in an error being thrown.

crypto module methods and properties#

crypto.constants#

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Returns an object containing commonly used constants for crypto and security related operations. The specific constants currently defined are described in Crypto Constants.

crypto.DEFAULT_ENCODING#

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The default encoding to use for functions that can take either strings or buffers. The default value is 'buffer', which makes methods default to Buffer objects.

The crypto.DEFAULT_ENCODING mechanism is provided for backwards compatibility with legacy programs that expect 'latin1' to be the default encoding.

New applications should expect the default to be 'buffer'. This property may become deprecated in a future Node.js release.

crypto.fips#

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Property for checking and controlling whether a FIPS compliant crypto provider is currently in use. Setting to true requires a FIPS build of Node.js.

crypto.createCipher(algorithm, password[, options])#

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Creates and returns a Cipher object that uses the given algorithm and password. Optional options argument controls stream behavior.

The algorithm is dependent on OpenSSL, examples are 'aes192', etc. On recent OpenSSL releases, openssl list-cipher-algorithms will display the available cipher algorithms.

The password is used to derive the cipher key and initialization vector (IV). The value must be either a 'latin1' encoded string, a Buffer, a TypedArray, or a DataView.

The implementation of crypto.createCipher() derives keys using the OpenSSL function EVP_BytesToKey with the digest algorithm set to MD5, one iteration, and no salt. The lack of salt allows dictionary attacks as the same password always creates the same key. The low iteration count and non-cryptographically secure hash algorithm allow passwords to be tested very rapidly.

In line with OpenSSL's recommendation to use pbkdf2 instead of EVP_BytesToKey it is recommended that developers derive a key and IV on their own using crypto.pbkdf2() and to use crypto.createCipheriv() to create the Cipher object. Users should not use ciphers with counter mode (e.g. CTR, GCM or CCM) in crypto.createCipher(). A warning is emitted when they are used in order to avoid the risk of IV reuse that causes vulnerabilities. For the case when IV is reused in GCM, see Nonce-Disrespecting Adversaries for details.

crypto.createCipheriv(algorithm, key, iv[, options])#

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Creates and returns a Cipher object, with the given algorithm, key and initialization vector (iv). Optional options argument controls stream behavior.

The algorithm is dependent on OpenSSL, examples are 'aes192', etc. On recent OpenSSL releases, openssl list-cipher-algorithms will display the available cipher algorithms.

The key is the raw key used by the algorithm and iv is an initialization vector. Both arguments must be 'utf8' encoded strings, Buffers, TypedArray, or DataViews.

crypto.createCredentials(details)#

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Stability: 0 - Deprecated: Use tls.createSecureContext() instead.

The crypto.createCredentials() method is a deprecated function for creating and returning a tls.SecureContext. It should not be used. Replace it with tls.createSecureContext() which has the exact same arguments and return value.

Returns a tls.SecureContext, as-if tls.createSecureContext() had been called.

crypto.createDecipher(algorithm, password[, options])#

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Creates and returns a Decipher object that uses the given algorithm and password (key). Optional options argument controls stream behavior.

The implementation of crypto.createDecipher() derives keys using the OpenSSL function EVP_BytesToKey with the digest algorithm set to MD5, one iteration, and no salt. The lack of salt allows dictionary attacks as the same password always creates the same key. The low iteration count and non-cryptographically secure hash algorithm allow passwords to be tested very rapidly.

In line with OpenSSL's recommendation to use pbkdf2 instead of EVP_BytesToKey it is recommended that developers derive a key and IV on their own using crypto.pbkdf2() and to use crypto.createDecipheriv() to create the Decipher object.

crypto.createDecipheriv(algorithm, key, iv[, options])#

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Creates and returns a Decipher object that uses the given algorithm, key and initialization vector (iv). Optional options argument controls stream behavior.

The algorithm is dependent on OpenSSL, examples are 'aes192', etc. On recent OpenSSL releases, openssl list-cipher-algorithms will display the available cipher algorithms.

The key is the raw key used by the algorithm and iv is an initialization vector. Both arguments must be 'utf8' encoded strings or buffers.

crypto.createDiffieHellman(prime[, primeEncoding][, generator][, generatorEncoding])#

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Creates a DiffieHellman key exchange object using the supplied prime and an optional specific generator.

The generator argument can be a number, string, or Buffer. If generator is not specified, the value 2 is used.

The primeEncoding and generatorEncoding arguments can be 'latin1', 'hex', or 'base64'.

If primeEncoding is specified, prime is expected to be a string; otherwise a Buffer, TypedArray, or DataView is expected.

If generatorEncoding is specified, generator is expected to be a string; otherwise a number, Buffer, TypedArray, or DataView is expected.

crypto.createDiffieHellman(primeLength[, generator])#

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Creates a DiffieHellman key exchange object and generates a prime of primeLength bits using an optional specific numeric generator. If generator is not specified, the value 2 is used.

crypto.createECDH(curveName)#

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Creates an Elliptic Curve Diffie-Hellman (ECDH) key exchange object using a predefined curve specified by the curveName string. Use crypto.getCurves() to obtain a list of available curve names. On recent OpenSSL releases, openssl ecparam -list_curves will also display the name and description of each available elliptic curve.

crypto.createHash(algorithm[, options])#

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Creates and returns a Hash object that can be used to generate hash digests using the given algorithm. Optional options argument controls stream behavior.

The algorithm is dependent on the available algorithms supported by the version of OpenSSL on the platform. Examples are 'sha256', 'sha512', etc. On recent releases of OpenSSL, openssl list-message-digest-algorithms will display the available digest algorithms.

Example: generating the sha256 sum of a file

const filename = process.argv[2];
const crypto = require('crypto');
const fs = require('fs');

const hash = crypto.createHash('sha256');

const input = fs.createReadStream(filename);
input.on('readable', () => {
  const data = input.read();
  if (data)
    hash.update(data);
  else {
    console.log(`${hash.digest('hex')} ${filename}`);
  }
});

crypto.createHmac(algorithm, key[, options])#

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Creates and returns an Hmac object that uses the given algorithm and key. Optional options argument controls stream behavior.

The algorithm is dependent on the available algorithms supported by the version of OpenSSL on the platform. Examples are 'sha256', 'sha512', etc. On recent releases of OpenSSL, openssl list-message-digest-algorithms will display the available digest algorithms.

The key is the HMAC key used to generate the cryptographic HMAC hash.

Example: generating the sha256 HMAC of a file

const filename = process.argv[2];
const crypto = require('crypto');
const fs = require('fs');

const hmac = crypto.createHmac('sha256', 'a secret');

const input = fs.createReadStream(filename);
input.on('readable', () => {
  const data = input.read();
  if (data)
    hmac.update(data);
  else {
    console.log(`${hmac.digest('hex')} ${filename}`);
  }
});

crypto.createSign(algorithm[, options])#

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Creates and returns a Sign object that uses the given algorithm. Use crypto.getHashes() to obtain an array of names of the available signing algorithms. Optional options argument controls the stream.Writable behavior.

crypto.createVerify(algorithm[, options])#

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Creates and returns a Verify object that uses the given algorithm. Use crypto.getHashes() to obtain an array of names of the available signing algorithms. Optional options argument controls the stream.Writable behavior.

crypto.getCiphers()#

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Returns an array with the names of the supported cipher algorithms.

Example:

const ciphers = crypto.getCiphers();
console.log(ciphers); // ['aes-128-cbc', 'aes-128-ccm', ...]

crypto.getCurves()#

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Returns an array with the names of the supported elliptic curves.

Example:

const curves = crypto.getCurves();
console.log(curves); // ['Oakley-EC2N-3', 'Oakley-EC2N-4', ...]

crypto.getDiffieHellman(groupName)#

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Creates a predefined DiffieHellman key exchange object. The supported groups are: 'modp1', 'modp2', 'modp5' (defined in RFC 2412, but see Caveats) and 'modp14', 'modp15', 'modp16', 'modp17', 'modp18' (defined in RFC 3526). The returned object mimics the interface of objects created by crypto.createDiffieHellman(), but will not allow changing the keys (with diffieHellman.setPublicKey() for example). The advantage of using this method is that the parties do not have to generate nor exchange a group modulus beforehand, saving both processor and communication time.

Example (obtaining a shared secret):

const crypto = require('crypto');
const alice = crypto.getDiffieHellman('modp14');
const bob = crypto.getDiffieHellman('modp14');

alice.generateKeys();
bob.generateKeys();

const aliceSecret = alice.computeSecret(bob.getPublicKey(), null, 'hex');
const bobSecret = bob.computeSecret(alice.getPublicKey(), null, 'hex');

/* aliceSecret and bobSecret should be the same */
console.log(aliceSecret === bobSecret);

crypto.getHashes()#

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Returns an array of the names of the supported hash algorithms, such as RSA-SHA256.

Example:

const hashes = crypto.getHashes();
console.log(hashes); // ['DSA', 'DSA-SHA', 'DSA-SHA1', ...]

crypto.pbkdf2(password, salt, iterations, keylen, digest, callback)#

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Provides an asynchronous Password-Based Key Derivation Function 2 (PBKDF2) implementation. A selected HMAC digest algorithm specified by digest is applied to derive a key of the requested byte length (keylen) from the password, salt and iterations.

The supplied callback function is called with two arguments: err and derivedKey. If an error occurs, err will be set; otherwise err will be null. The successfully generated derivedKey will be passed as a Buffer.

The iterations argument must be a number set as high as possible. The higher the number of iterations, the more secure the derived key will be, but will take a longer amount of time to complete.

The salt should also be as unique as possible. It is recommended that the salts are random and their lengths are greater than 16 bytes. See NIST SP 800-132 for details.

Example:

const crypto = require('crypto');
crypto.pbkdf2('secret', 'salt', 100000, 64, 'sha512', (err, derivedKey) => {
  if (err) throw err;
  console.log(derivedKey.toString('hex'));  // '3745e48...08d59ae'
});

An array of supported digest functions can be retrieved using crypto.getHashes().

Note that this API uses libuv's threadpool, which can have surprising and negative performance implications for some applications, see the UV_THREADPOOL_SIZE documentation for more information.

crypto.pbkdf2Sync(password, salt, iterations, keylen, digest)#

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Provides a synchronous Password-Based Key Derivation Function 2 (PBKDF2) implementation. A selected HMAC digest algorithm specified by digest is applied to derive a key of the requested byte length (keylen) from the password, salt and iterations.

If an error occurs an Error will be thrown, otherwise the derived key will be returned as a Buffer.

The iterations argument must be a number set as high as possible. The higher the number of iterations, the more secure the derived key will be, but will take a longer amount of time to complete.

The salt should also be as unique as possible. It is recommended that the salts are random and their lengths are greater than 16 bytes. See NIST SP 800-132 for details.

Example:

const crypto = require('crypto');
const key = crypto.pbkdf2Sync('secret', 'salt', 100000, 64, 'sha512');
console.log(key.toString('hex'));  // '3745e48...08d59ae'

An array of supported digest functions can be retrieved using crypto.getHashes().

crypto.privateDecrypt(privateKey, buffer)#

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  • privateKey <Object> | <string>
    • key <string> A PEM encoded private key.
    • passphrase <string> An optional passphrase for the private key.
    • padding <crypto.constants> An optional padding value defined in crypto.constants, which may be: crypto.constants.RSA_NO_PADDING, RSA_PKCS1_PADDING, or crypto.constants.RSA_PKCS1_OAEP_PADDING.
  • buffer <Buffer> | <TypedArray> | <DataView>
  • Returns: <Buffer> A new Buffer with the decrypted content.

Decrypts buffer with privateKey.

privateKey can be an object or a string. If privateKey is a string, it is treated as the key with no passphrase and will use RSA_PKCS1_OAEP_PADDING.

crypto.privateEncrypt(privateKey, buffer)#

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  • privateKey <Object> | <string>
    • key <string> A PEM encoded private key.
    • passphrase <string> An optional passphrase for the private key.
    • padding <crypto.constants> An optional padding value defined in crypto.constants, which may be: crypto.constants.RSA_NO_PADDING or RSA_PKCS1_PADDING.
  • buffer <Buffer> | <TypedArray> | <DataView>
  • Returns: <Buffer> A new Buffer with the encrypted content.

Encrypts buffer with privateKey.

privateKey can be an object or a string. If privateKey is a string, it is treated as the key with no passphrase and will use RSA_PKCS1_PADDING.

crypto.publicDecrypt(key, buffer)#

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  • key <Object> | <string>
    • key <string> A PEM encoded public or private key.
    • passphrase <string> An optional passphrase for the private key.
    • padding <crypto.constants> An optional padding value defined in crypto.constants, which may be: crypto.constants.RSA_NO_PADDING or RSA_PKCS1_PADDING.
  • buffer <Buffer> | <TypedArray> | <DataView>
  • Returns: <Buffer> A new Buffer with the decrypted content.

Decrypts buffer with key.

key can be an object or a string. If key is a string, it is treated as the key with no passphrase and will use RSA_PKCS1_PADDING.

Because RSA public keys can be derived from private keys, a private key may be passed instead of a public key.

crypto.publicEncrypt(key, buffer)#

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  • key <Object> | <string>
    • key <string> A PEM encoded public or private key.
    • passphrase <string> An optional passphrase for the private key.
    • padding <crypto.constants> An optional padding value defined in crypto.constants, which may be: crypto.constants.RSA_NO_PADDING, RSA_PKCS1_PADDING, or crypto.constants.RSA_PKCS1_OAEP_PADDING.
  • buffer <Buffer> | <TypedArray> | <DataView>
  • Returns: <Buffer> A new Buffer with the encrypted content.

Encrypts the content of buffer with key and returns a new Buffer with encrypted content.

key can be an object or a string. If key is a string, it is treated as the key with no passphrase and will use RSA_PKCS1_OAEP_PADDING.

Because RSA public keys can be derived from private keys, a private key may be passed instead of a public key.

crypto.randomBytes(size[, callback])#

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生成加密强伪随机数据. size参数是指示要生成的字节数的数字。

如果提供 callback回调函数 ,这些字节是异步生成的并且使用两个参数调用callback函数:errbuf。 如果发生错误, err是一个Error对象; 否则为null. 该buf参数是包含生成字节的Buffer

// Asynchronous
const crypto = require('crypto');
crypto.randomBytes(256, (err, buf) => {
  if (err) throw err;
  console.log(`${buf.length} bytes of random data: ${buf.toString('hex')}`);
});

如果不提供 callback回调函数, 生成随机字节同步并返回为Buffer.如果出现错误将会抛出生成字节有问题。

// Synchronous
const buf = crypto.randomBytes(256);
console.log(
  `${buf.length} bytes of random data: ${buf.toString('hex')}`);

crypto.randomBytes()方法将阻塞,直到有足够的熵. 这通常不会超过几毫秒. 唯一的时间 当生成随机字节可能会阻塞更长的时间 时间是开机后,当整个系统的熵低时

Note that this API uses libuv's threadpool, which can have surprising and negative performance implications for some applications, see the UV_THREADPOOL_SIZE documentation for more information.

crypto.randomFillSync(buffer[, offset][, size])#

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Synchronous version of crypto.randomFill().

Returns buffer

const buf = Buffer.alloc(10);
console.log(crypto.randomFillSync(buf).toString('hex'));

crypto.randomFillSync(buf, 5);
console.log(buf.toString('hex'));

// The above is equivalent to the following:
crypto.randomFillSync(buf, 5, 5);
console.log(buf.toString('hex'));

crypto.randomFill(buffer[, offset][, size], callback)#

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This function is similar to crypto.randomBytes() but requires the first argument to be a Buffer that will be filled. It also requires that a callback is passed in.

If the callback function is not provided, an error will be thrown.

const buf = Buffer.alloc(10);
crypto.randomFill(buf, (err, buf) => {
  if (err) throw err;
  console.log(buf.toString('hex'));
});

crypto.randomFill(buf, 5, (err, buf) => {
  if (err) throw err;
  console.log(buf.toString('hex'));
});

// The above is equivalent to the following:
crypto.randomFill(buf, 5, 5, (err, buf) => {
  if (err) throw err;
  console.log(buf.toString('hex'));
});

Note that this API uses libuv's threadpool, which can have surprising and negative performance implications for some applications, see the UV_THREADPOOL_SIZE documentation for more information.

crypto.setEngine(engine[, flags])#

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  • engine <string>
  • flags <crypto.constants> Defaults to crypto.constants.ENGINE_METHOD_ALL.

Load and set the engine for some or all OpenSSL functions (selected by flags).

engine could be either an id or a path to the engine's shared library.

The optional flags argument uses ENGINE_METHOD_ALL by default. The flags is a bit field taking one of or a mix of the following flags (defined in crypto.constants):

  • crypto.constants.ENGINE_METHOD_RSA
  • crypto.constants.ENGINE_METHOD_DSA
  • crypto.constants.ENGINE_METHOD_DH
  • crypto.constants.ENGINE_METHOD_RAND
  • crypto.constants.ENGINE_METHOD_ECDH
  • crypto.constants.ENGINE_METHOD_ECDSA
  • crypto.constants.ENGINE_METHOD_CIPHERS
  • crypto.constants.ENGINE_METHOD_DIGESTS
  • crypto.constants.ENGINE_METHOD_STORE
  • crypto.constants.ENGINE_METHOD_PKEY_METHS
  • crypto.constants.ENGINE_METHOD_PKEY_ASN1_METHS
  • crypto.constants.ENGINE_METHOD_ALL
  • crypto.constants.ENGINE_METHOD_NONE

crypto.timingSafeEqual(a, b)#

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Returns true if a is equal to b, without leaking timing information that would allow an attacker to guess one of the values. This is suitable for comparing HMAC digests or secret values like authentication cookies or capability urls.

a and b must both be Buffers, TypedArrays, or DataViews, and they must have the same length.

Note: Use of crypto.timingSafeEqual does not guarantee that the surrounding code is timing-safe. Care should be taken to ensure that the surrounding code does not introduce timing vulnerabilities.

Notes#

Legacy Streams API (pre Node.js v0.10)#

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The Crypto module was added to Node.js before there was the concept of a unified Stream API, and before there were Buffer objects for handling binary data. As such, the many of the crypto defined classes have methods not typically found on other Node.js classes that implement the streams API (e.g. update(), final(), or digest()). Also, many methods accepted and returned 'latin1' encoded strings by default rather than Buffers. This default was changed after Node.js v0.8 to use Buffer objects by default instead.

Recent ECDH Changes#

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Usage of ECDH with non-dynamically generated key pairs has been simplified. Now, ecdh.setPrivateKey() can be called with a preselected private key and the associated public point (key) will be computed and stored in the object. This allows code to only store and provide the private part of the EC key pair. ecdh.setPrivateKey() now also validates that the private key is valid for the selected curve.

The ecdh.setPublicKey() method is now deprecated as its inclusion in the API is not useful. Either a previously stored private key should be set, which automatically generates the associated public key, or ecdh.generateKeys() should be called. The main drawback of using ecdh.setPublicKey() is that it can be used to put the ECDH key pair into an inconsistent state.

Support for weak or compromised algorithms#

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The crypto module still supports some algorithms which are already compromised and are not currently recommended for use. The API also allows the use of ciphers and hashes with a small key size that are considered to be too weak for safe use.

Users should take full responsibility for selecting the crypto algorithm and key size according to their security requirements.

Based on the recommendations of NIST SP 800-131A:

  • MD5 and SHA-1 are no longer acceptable where collision resistance is required such as digital signatures.
  • The key used with RSA, DSA and DH algorithms is recommended to have at least 2048 bits and that of the curve of ECDSA and ECDH at least 224 bits, to be safe to use for several years.
  • The DH groups of modp1, modp2 and modp5 have a key size smaller than 2048 bits and are not recommended.

See the reference for other recommendations and details.

Crypto Constants#

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The following constants exported by crypto.constants apply to various uses of the crypto, tls, and https modules and are generally specific to OpenSSL.

OpenSSL Options#

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Constant Description
SSL_OP_ALL Applies multiple bug workarounds within OpenSSL. See https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html for detail.
SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION Allows legacy insecure renegotiation between OpenSSL and unpatched clients or servers. See https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html.
SSL_OP_CIPHER_SERVER_PREFERENCE Attempts to use the server's preferences instead of the client's when selecting a cipher. Behavior depends on protocol version. See https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html.
SSL_OP_CISCO_ANYCONNECT Instructs OpenSSL to use Cisco's "speshul" version of DTLS_BAD_VER.
SSL_OP_COOKIE_EXCHANGE Instructs OpenSSL to turn on cookie exchange.
SSL_OP_CRYPTOPRO_TLSEXT_BUG Instructs OpenSSL to add server-hello extension from an early version of the cryptopro draft.
SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS Instructs OpenSSL to disable a SSL 3.0/TLS 1.0 vulnerability workaround added in OpenSSL 0.9.6d.
SSL_OP_EPHEMERAL_RSA Instructs OpenSSL to always use the tmp_rsa key when performing RSA operations.
SSL_OP_LEGACY_SERVER_CONNECT Allows initial connection to servers that do not support RI.
SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER
SSL_OP_MICROSOFT_SESS_ID_BUG
SSL_OP_MSIE_SSLV2_RSA_PADDING Instructs OpenSSL to disable the workaround for a man-in-the-middle protocol-version vulnerability in the SSL 2.0 server implementation.
SSL_OP_NETSCAPE_CA_DN_BUG
SSL_OP_NETSCAPE_CHALLENGE_BUG
SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG
SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG
SSL_OP_NO_COMPRESSION Instructs OpenSSL to disable support for SSL/TLS compression.
SSL_OP_NO_QUERY_MTU
SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION Instructs OpenSSL to always start a new session when performing renegotiation.
SSL_OP_NO_SSLv2 Instructs OpenSSL to turn off SSL v2
SSL_OP_NO_SSLv3 Instructs OpenSSL to turn off SSL v3
SSL_OP_NO_TICKET Instructs OpenSSL to disable use of RFC4507bis tickets.
SSL_OP_NO_TLSv1 Instructs OpenSSL to turn off TLS v1
SSL_OP_NO_TLSv1_1 Instructs OpenSSL to turn off TLS v1.1
SSL_OP_NO_TLSv1_2 Instructs OpenSSL to turn off TLS v1.2
SSL_OP_PKCS1_CHECK_1
SSL_OP_PKCS1_CHECK_2
SSL_OP_SINGLE_DH_USE Instructs OpenSSL to always create a new key when using temporary/ephemeral DH parameters.
SSL_OP_SINGLE_ECDH_USE Instructs OpenSSL to always create a new key when using temporary/ephemeral ECDH parameters.
SSL_OP_SSLEAY_080_CLIENT_DH_BUG
SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG
SSL_OP_TLS_BLOCK_PADDING_BUG
SSL_OP_TLS_D5_BUG
SSL_OP_TLS_ROLLBACK_BUG Instructs OpenSSL to disable version rollback attack detection.

OpenSSL Engine Constants#

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Constant Description
ENGINE_METHOD_RSA Limit engine usage to RSA
ENGINE_METHOD_DSA Limit engine usage to DSA
ENGINE_METHOD_DH Limit engine usage to DH
ENGINE_METHOD_RAND Limit engine usage to RAND
ENGINE_METHOD_ECDH Limit engine usage to ECDH
ENGINE_METHOD_ECDSA Limit engine usage to ECDSA
ENGINE_METHOD_CIPHERS Limit engine usage to CIPHERS
ENGINE_METHOD_DIGESTS Limit engine usage to DIGESTS
ENGINE_METHOD_STORE Limit engine usage to STORE
ENGINE_METHOD_PKEY_METHS Limit engine usage to PKEY_METHDS
ENGINE_METHOD_PKEY_ASN1_METHS Limit engine usage to PKEY_ASN1_METHS
ENGINE_METHOD_ALL
ENGINE_METHOD_NONE

Other OpenSSL Constants#

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Constant Description
DH_CHECK_P_NOT_SAFE_PRIME
DH_CHECK_P_NOT_PRIME
DH_UNABLE_TO_CHECK_GENERATOR
DH_NOT_SUITABLE_GENERATOR
NPN_ENABLED
ALPN_ENABLED
RSA_PKCS1_PADDING
RSA_SSLV23_PADDING
RSA_NO_PADDING
RSA_PKCS1_OAEP_PADDING
RSA_X931_PADDING
RSA_PKCS1_PSS_PADDING
RSA_PSS_SALTLEN_DIGEST Sets the salt length for RSA_PKCS1_PSS_PADDING to the digest size when signing or verifying.
RSA_PSS_SALTLEN_MAX_SIGN Sets the salt length for RSA_PKCS1_PSS_PADDING to the maximum permissible value when signing data.
RSA_PSS_SALTLEN_AUTO Causes the salt length for RSA_PKCS1_PSS_PADDING to be determined automatically when verifying a signature.
POINT_CONVERSION_COMPRESSED
POINT_CONVERSION_UNCOMPRESSED
POINT_CONVERSION_HYBRID

Node.js Crypto Constants#

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Constant Description
defaultCoreCipherList Specifies the built-in default cipher list used by Node.js.
defaultCipherList Specifies the active default cipher list used by the current Node.js process.