{ "source": "doc/api/crypto.md", "modules": [ { "textRaw": "Crypto", "name": "crypto", "stability": 2, "stabilityText": "Stable", "desc": "
The crypto
module provides cryptographic functionality that includes a set of\nwrappers for OpenSSL's hash, HMAC, cipher, decipher, sign and verify functions.
Use require('crypto')
to access this module.
const crypto = require('crypto');\n\nconst secret = 'abcdefg';\nconst hash = crypto.createHmac('sha256', secret)\n .update('I love cupcakes')\n .digest('hex');\nconsole.log(hash);\n // Prints:\n // c0fa1bc00531bd78ef38c628449c5102aeabd49b5dc3a2a516ea6ea959d6658e\n
\n",
"modules": [
{
"textRaw": "Determining if crypto support is unavailable",
"name": "determining_if_crypto_support_is_unavailable",
"desc": "It is possible for Node.js to be built without including support for the\ncrypto
module. In such cases, calling require('crypto')
will result in an\nerror being thrown.
var crypto;\ntry {\n crypto = require('crypto');\n} catch (err) {\n console.log('crypto support is disabled!');\n}\n
\n",
"type": "module",
"displayName": "Determining if crypto support is unavailable"
},
{
"textRaw": "Notes",
"name": "notes",
"modules": [
{
"textRaw": "Legacy Streams API (pre Node.js v0.10)",
"name": "legacy_streams_api_(pre_node.js_v0.10)",
"desc": "The Crypto module was added to Node.js before there was the concept of a\nunified Stream API, and before there were [Buffer
][] objects for handling\nbinary data. As such, the many of the crypto
defined classes have methods not\ntypically found on other Node.js classes that implement the [streams][stream]\nAPI (e.g. update()
, final()
, or digest()
). Also, many methods accepted\nand returned 'binary'
encoded strings by default rather than Buffers. This\ndefault was changed after Node.js v0.8 to use [Buffer
][] objects by default\ninstead.
Usage of ECDH
with non-dynamically generated key pairs has been simplified.\nNow, [ecdh.setPrivateKey()
][] can be called with a preselected private key\nand the associated public point (key) will be computed and stored in the object.\nThis allows code to only store and provide the private part of the EC key pair.\n[ecdh.setPrivateKey()
][] now also validates that the private key is valid for\nthe selected curve.
The [ecdh.setPublicKey()
][] method is now deprecated as its inclusion in the\nAPI is not useful. Either a previously stored private key should be set, which\nautomatically generates the associated public key, or [ecdh.generateKeys()
][]\nshould be called. The main drawback of using [ecdh.setPublicKey()
][] is that\nit can be used to put the ECDH key pair into an inconsistent state.
The crypto
module still supports some algorithms which are already\ncompromised and are not currently recommended for use. The API also allows\nthe use of ciphers and hashes with a small key size that are considered to be\ntoo weak for safe use.
Users should take full responsibility for selecting the crypto\nalgorithm and key size according to their security requirements.
\nBased on the recommendations of [NIST SP 800-131A][]:
\nmodp1
, modp2
and modp5
have a key size\nsmaller than 2048 bits and are not recommended.See the reference for other recommendations and details.
\n", "type": "module", "displayName": "Support for weak or compromised algorithms" } ], "type": "module", "displayName": "Notes" }, { "textRaw": "Crypto Constants", "name": "crypto_constants", "desc": "The following constants exported by crypto.constants
apply to various uses of \nthe crypto
, tls
, and https
modules and are generally specific to OpenSSL.
Constant | \nDescription | \n
---|---|
SSL_OP_ALL | \n Applies multiple bug workarounds within OpenSSL. See\n https://www.openssl.org/docs/manmaster/ssl/SSL_CTX_set_options.html for\n detail. | \n
SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION | \n Allows legacy insecure renegotiation between OpenSSL and unpatched\n clients or servers. See \n https://www.openssl.org/docs/manmaster/ssl/SSL_CTX_set_options.html. | \n
SSL_OP_CIPHER_SERVER_PREFERENCE | \n Uses the server's preferences instead of the clients when selecting a\n cipher. See \n https://www.openssl.org/docs/manmaster/ssl/SSL_CTX_set_options.html. | \n
SSL_OP_CISCO_ANYCONNECT | \n Instructs OpenSSL to use Cisco's "speshul" version of DTLS_BAD_VER. | \n
SSL_OP_COOKIE_EXCHANGE | \n Instructs OpenSSL to turn on cookie exchange. | \n
SSL_OP_CRYPTOPRO_TLSEXT_BUG | \n Instructs OpenSSL to add server-hello extension from an early version\n of the cryptopro draft. | \n
SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS | \n Instructs OpenSSL to disable a SSL 3.0/TLS 1.0 vulnerability\n workaround added in OpenSSL 0.9.6d. | \n
SSL_OP_EPHEMERAL_RSA | \n Instructs OpenSSL to always use the tmp_rsa key when performing RSA\n operations. | \n
SSL_OP_LEGACY_SERVER_CONNECT | \n Allow initial connection to servers that do not support RI. | \n
SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER | \n \n |
SSL_OP_MICROSOFT_SESS_ID_BUG | \n \n |
SSL_OP_MSIE_SSLV2_RSA_PADDING | \n Instructs OpenSSL to disable the workaround for a man-in-the-middle\n protocol-version vulnerability in the SSL 2.0 server implementation. | \n
SSL_OP_NETSCAPE_CA_DN_BUG | \n \n |
SSL_OP_NETSCAPE_CHALLENGE_BUG | \n \n |
SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG | \n \n |
SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG | \n \n |
SSL_OP_NO_COMPRESSION | \n Instructs OpenSSL to disable support for SSL/TLS compression. | \n
SSL_OP_NO_QUERY_MTU | \n \n |
SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION | \n Instructs OpenSSL to always start a new session when performing\n renegotiation. | \n
SSL_OP_NO_SSLv2 | \n Instructs OpenSSL to turn off SSL v2 | \n
SSL_OP_NO_SSLv3 | \n Instructs OpenSSL to turn off SSL v3 | \n
SSL_OP_NO_TICKET | \n Instructs OpenSSL to disable use of RFC4507bis tickets. | \n
SSL_OP_NO_TLSv1 | \n Instructs OpenSSL to turn off TLS v1 | \n
SSL_OP_NO_TLSv1_1 | \n Instructs OpenSSL to turn off TLS v1.1 | \n
SSL_OP_NO_TLSv1_2 | \n Instructs OpenSSL to turn off TLS v1.2 | \nSSL_OP_PKCS1_CHECK_1 | \n \n \n |
SSL_OP_PKCS1_CHECK_2 | \n \n |
SSL_OP_SINGLE_DH_USE | \n Instructs OpenSSL to always create a new key when using\n temporary/ephemeral DH parameters. | \n
SSL_OP_SINGLE_ECDH_USE | \n Instructs OpenSSL to always create a new key when using\n temporary/ephemeral ECDH parameters. | \nSSL_OP_SSLEAY_080_CLIENT_DH_BUG | \n \n \n |
SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG | \n \n |
SSL_OP_TLS_BLOCK_PADDING_BUG | \n \n |
SSL_OP_TLS_D5_BUG | \n \n |
SSL_OP_TLS_ROLLBACK_BUG | \n Instructs OpenSSL to disable version rollback attack detection. | \n
Constant | \nDescription | \n
---|---|
ENGINE_METHOD_RSA | \n Limit engine usage to RSA | \n
ENGINE_METHOD_DSA | \n Limit engine usage to DSA | \n
ENGINE_METHOD_DH | \n Limit engine usage to DH | \n
ENGINE_METHOD_RAND | \n Limit engine usage to RAND | \n
ENGINE_METHOD_ECDH | \n Limit engine usage to ECDH | \n
ENGINE_METHOD_ECDSA | \n Limit engine usage to ECDSA | \n
ENGINE_METHOD_CIPHERS | \n Limit engine usage to CIPHERS | \n
ENGINE_METHOD_DIGESTS | \n Limit engine usage to DIGESTS | \n
ENGINE_METHOD_STORE | \n Limit engine usage to STORE | \n
ENGINE_METHOD_PKEY_METHS | \n Limit engine usage to PKEY_METHDS | \n
ENGINE_METHOD_PKEY_ASN1_METHS | \n Limit engine usage to PKEY_ASN1_METHS | \n
ENGINE_METHOD_ALL | \n \n |
ENGINE_METHOD_NONE | \n \n |
Constant | \nDescription | \n
---|---|
DH_CHECK_P_NOT_SAFE_PRIME | \n \n |
DH_CHECK_P_NOT_PRIME | \n \n |
DH_UNABLE_TO_CHECK_GENERATOR | \n \n |
DH_NOT_SUITABLE_GENERATOR | \n \n |
NPN_ENABLED | \n \n |
ALPN_ENABLED | \n \n |
RSA_PKCS1_PADDING | \n \n |
RSA_SSLV23_PADDING | \n \n |
RSA_NO_PADDING | \n \n |
RSA_PKCS1_OAEP_PADDING | \n \n |
RSA_X931_PADDING | \n \n |
RSA_PKCS1_PSS_PADDING | \n \n |
POINT_CONVERSION_COMPRESSED | \n \n |
POINT_CONVERSION_UNCOMPRESSED | \n \n |
POINT_CONVERSION_HYBRID | \n \n |
Constant | \nDescription | \n
---|---|
defaultCoreCipherList | \n Specifies the built-in default cipher list used by Node.js. | \n
defaultCipherList | \n Specifies the active default cipher list used by the current Node.js\n process. | \n
SPKAC is a Certificate Signing Request mechanism originally implemented by\nNetscape and now specified formally as part of [HTML5's keygen
element][].
The crypto
module provides the Certificate
class for working with SPKAC\ndata. The most common usage is handling output generated by the HTML5\n<keygen>
element. Node.js uses [OpenSSL's SPKAC implementation][] internally.
Instances of the Certificate
class can be created using the new
keyword\nor by calling crypto.Certificate()
as a function:
const crypto = require('crypto');\n\nconst cert1 = new crypto.Certificate();\nconst cert2 = crypto.Certificate();\n
\n",
"signatures": [
{
"params": []
}
]
},
{
"textRaw": "certificate.exportChallenge(spkac)",
"type": "method",
"name": "exportChallenge",
"desc": "The spkac
data structure includes a public key and a challenge. The\ncertificate.exportChallenge()
returns the challenge component in the\nform of a Node.js [Buffer
][]. The spkac
argument can be either a string\nor a [Buffer
][].
const cert = require('crypto').Certificate();\nconst spkac = getSpkacSomehow();\nconst challenge = cert.exportChallenge(spkac);\nconsole.log(challenge.toString('utf8'));\n // Prints the challenge as a UTF8 string\n
\n",
"signatures": [
{
"params": [
{
"name": "spkac"
}
]
}
]
},
{
"textRaw": "certificate.exportPublicKey(spkac)",
"type": "method",
"name": "exportPublicKey",
"desc": "The spkac
data structure includes a public key and a challenge. The\ncertificate.exportPublicKey()
returns the public key component in the\nform of a Node.js [Buffer
][]. The spkac
argument can be either a string\nor a [Buffer
][].
const cert = require('crypto').Certificate();\nconst spkac = getSpkacSomehow();\nconst publicKey = cert.exportPublicKey(spkac);\nconsole.log(publicKey);\n // Prints the public key as <Buffer ...>\n
\n",
"signatures": [
{
"params": [
{
"name": "spkac"
}
]
}
]
},
{
"textRaw": "certificate.verifySpkac(spkac)",
"type": "method",
"name": "verifySpkac",
"desc": "Returns true
if the given spkac
data structure is valid, false
otherwise.\nThe spkac
argument must be a Node.js [Buffer
][].
const cert = require('crypto').Certificate();\nconst spkac = getSpkacSomehow();\nconsole.log(cert.verifySpkac(Buffer.from(spkac)));\n // Prints true or false\n
\n",
"signatures": [
{
"params": [
{
"name": "spkac"
}
]
}
]
}
]
},
{
"textRaw": "Class: Cipher",
"type": "class",
"name": "Cipher",
"desc": "Instances of the Cipher
class are used to encrypt data. The class can be\nused in one of two ways:
cipher.update()
][] and [cipher.final()
][] methods to produce\nthe encrypted data.The [crypto.createCipher()
][] or [crypto.createCipheriv()
][] methods are\nused to create Cipher
instances. Cipher
objects are not to be created\ndirectly using the new
keyword.
Example: Using Cipher
objects as streams:
const crypto = require('crypto');\nconst cipher = crypto.createCipher('aes192', 'a password');\n\nvar encrypted = '';\ncipher.on('readable', () => {\n var data = cipher.read();\n if (data)\n encrypted += data.toString('hex');\n});\ncipher.on('end', () => {\n console.log(encrypted);\n // Prints: ca981be48e90867604588e75d04feabb63cc007a8f8ad89b10616ed84d815504\n});\n\ncipher.write('some clear text data');\ncipher.end();\n
\nExample: Using Cipher
and piped streams:
const crypto = require('crypto');\nconst fs = require('fs');\nconst cipher = crypto.createCipher('aes192', 'a password');\n\nconst input = fs.createReadStream('test.js');\nconst output = fs.createWriteStream('test.enc');\n\ninput.pipe(cipher).pipe(output);\n
\nExample: Using the [cipher.update()
][] and [cipher.final()
][] methods:
const crypto = require('crypto');\nconst cipher = crypto.createCipher('aes192', 'a password');\n\nvar encrypted = cipher.update('some clear text data', 'utf8', 'hex');\nencrypted += cipher.final('hex');\nconsole.log(encrypted);\n // Prints: ca981be48e90867604588e75d04feabb63cc007a8f8ad89b10616ed84d815504\n
\n",
"methods": [
{
"textRaw": "cipher.final([output_encoding])",
"type": "method",
"name": "final",
"desc": "Returns any remaining enciphered contents. If output_encoding
\nparameter is one of 'binary'
, 'base64'
or 'hex'
, a string is returned.\nIf an output_encoding
is not provided, a [Buffer
][] is returned.
Once the cipher.final()
method has been called, the Cipher
object can no\nlonger be used to encrypt data. Attempts to call cipher.final()
more than\nonce will result in an error being thrown.
When using an authenticated encryption mode (only GCM
is currently\nsupported), the cipher.setAAD()
method sets the value used for the\nadditional authenticated data (AAD) input parameter.
When using an authenticated encryption mode (only GCM
is currently\nsupported), the cipher.getAuthTag()
method returns a [Buffer
][] containing\nthe authentication tag that has been computed from the given data.
The cipher.getAuthTag()
method should only be called after encryption has\nbeen completed using the [cipher.final()
][] method.
When using block encryption algorithms, the Cipher
class will automatically\nadd padding to the input data to the appropriate block size. To disable the\ndefault padding call cipher.setAutoPadding(false)
.
When auto_padding
is false
, the length of the entire input data must be a\nmultiple of the cipher's block size or [cipher.final()
][] will throw an Error.\nDisabling automatic padding is useful for non-standard padding, for instance\nusing 0x0
instead of PKCS padding.
The cipher.setAutoPadding()
method must be called before [cipher.final()
][].
Updates the cipher with data
. If the input_encoding
argument is given,\nit's value must be one of 'utf8'
, 'ascii'
, or 'binary'
and the data
\nargument is a string using the specified encoding. If the input_encoding
\nargument is not given, data
must be a [Buffer
][]. If data
is a\n[Buffer
][] then input_encoding
is ignored.
The output_encoding
specifies the output format of the enciphered\ndata, and can be 'binary'
, 'base64'
or 'hex'
. If the output_encoding
\nis specified, a string using the specified encoding is returned. If no\noutput_encoding
is provided, a [Buffer
][] is returned.
The cipher.update()
method can be called multiple times with new data until\n[cipher.final()
][] is called. Calling cipher.update()
after\n[cipher.final()
][] will result in an error being thrown.
Instances of the Decipher
class are used to decrypt data. The class can be\nused in one of two ways:
decipher.update()
][] and [decipher.final()
][] methods to\nproduce the unencrypted data.The [crypto.createDecipher()
][] or [crypto.createDecipheriv()
][] methods are\nused to create Decipher
instances. Decipher
objects are not to be created\ndirectly using the new
keyword.
Example: Using Decipher
objects as streams:
const crypto = require('crypto');\nconst decipher = crypto.createDecipher('aes192', 'a password');\n\nvar decrypted = '';\ndecipher.on('readable', () => {\n var data = decipher.read();\n if (data)\n decrypted += data.toString('utf8');\n});\ndecipher.on('end', () => {\n console.log(decrypted);\n // Prints: some clear text data\n});\n\nvar encrypted = 'ca981be48e90867604588e75d04feabb63cc007a8f8ad89b10616ed84d815504';\ndecipher.write(encrypted, 'hex');\ndecipher.end();\n
\nExample: Using Decipher
and piped streams:
const crypto = require('crypto');\nconst fs = require('fs');\nconst decipher = crypto.createDecipher('aes192', 'a password');\n\nconst input = fs.createReadStream('test.enc');\nconst output = fs.createWriteStream('test.js');\n\ninput.pipe(decipher).pipe(output);\n
\nExample: Using the [decipher.update()
][] and [decipher.final()
][] methods:
const crypto = require('crypto');\nconst decipher = crypto.createDecipher('aes192', 'a password');\n\nvar encrypted = 'ca981be48e90867604588e75d04feabb63cc007a8f8ad89b10616ed84d815504';\nvar decrypted = decipher.update(encrypted, 'hex', 'utf8');\ndecrypted += decipher.final('utf8');\nconsole.log(decrypted);\n // Prints: some clear text data\n
\n",
"methods": [
{
"textRaw": "decipher.final([output_encoding])",
"type": "method",
"name": "final",
"desc": "Returns any remaining deciphered contents. If output_encoding
\nparameter is one of 'binary'
, 'base64'
or 'hex'
, a string is returned.\nIf an output_encoding
is not provided, a [Buffer
][] is returned.
Once the decipher.final()
method has been called, the Decipher
object can\nno longer be used to decrypt data. Attempts to call decipher.final()
more\nthan once will result in an error being thrown.
When using an authenticated encryption mode (only GCM
is currently\nsupported), the cipher.setAAD()
method sets the value used for the\nadditional authenticated data (AAD) input parameter.
When using an authenticated encryption mode (only GCM
is currently\nsupported), the decipher.setAuthTag()
method is used to pass in the\nreceived authentication tag. If no tag is provided, or if the cipher text\nhas been tampered with, [decipher.final()
][] with throw, indicating that the\ncipher text should be discarded due to failed authentication.
When data has been encrypted without standard block padding, calling\ndecipher.setAutoPadding(false)
will disable automatic padding to prevent\n[decipher.final()
][] from checking for and removing padding.
Turning auto padding off will only work if the input data's length is a\nmultiple of the ciphers block size.
\nThe decipher.setAutoPadding()
method must be called before\n[decipher.update()
][].
Updates the decipher with data
. If the input_encoding
argument is given,\nit's value must be one of 'binary'
, 'base64'
, or 'hex'
and the data
\nargument is a string using the specified encoding. If the input_encoding
\nargument is not given, data
must be a [Buffer
][]. If data
is a\n[Buffer
][] then input_encoding
is ignored.
The output_encoding
specifies the output format of the enciphered\ndata, and can be 'binary'
, 'ascii'
or 'utf8'
. If the output_encoding
\nis specified, a string using the specified encoding is returned. If no\noutput_encoding
is provided, a [Buffer
][] is returned.
The decipher.update()
method can be called multiple times with new data until\n[decipher.final()
][] is called. Calling decipher.update()
after\n[decipher.final()
][] will result in an error being thrown.
The DiffieHellman
class is a utility for creating Diffie-Hellman key\nexchanges.
Instances of the DiffieHellman
class can be created using the\n[crypto.createDiffieHellman()
][] function.
const crypto = require('crypto');\nconst assert = require('assert');\n\n// Generate Alice's keys...\nconst alice = crypto.createDiffieHellman(2048);\nconst alice_key = alice.generateKeys();\n\n// Generate Bob's keys...\nconst bob = crypto.createDiffieHellman(alice.getPrime(), alice.getGenerator());\nconst bob_key = bob.generateKeys();\n\n// Exchange and generate the secret...\nconst alice_secret = alice.computeSecret(bob_key);\nconst bob_secret = bob.computeSecret(alice_key);\n\n// OK\nassert.equal(alice_secret.toString('hex'), bob_secret.toString('hex'));\n
\n",
"methods": [
{
"textRaw": "diffieHellman.computeSecret(other_public_key[, input_encoding][, output_encoding])",
"type": "method",
"name": "computeSecret",
"desc": "Computes the shared secret using other_public_key
as the other\nparty's public key and returns the computed shared secret. The supplied\nkey is interpreted using the specified input_encoding
, and secret is\nencoded using specified output_encoding
. Encodings can be\n'binary'
, 'hex'
, or 'base64'
. If the input_encoding
is not\nprovided, other_public_key
is expected to be a [Buffer
][].
If output_encoding
is given a string is returned; otherwise, a\n[Buffer
][] is returned.
Generates private and public Diffie-Hellman key values, and returns\nthe public key in the specified encoding
. This key should be\ntransferred to the other party. Encoding can be 'binary'
, 'hex'
,\nor 'base64'
. If encoding
is provided a string is returned; otherwise a\n[Buffer
][] is returned.
Returns the Diffie-Hellman generator in the specified encoding
, which can\nbe 'binary'
, 'hex'
, or 'base64'
. If encoding
is provided a string is\nreturned; otherwise a [Buffer
][] is returned.
Returns the Diffie-Hellman prime in the specified encoding
, which can\nbe 'binary'
, 'hex'
, or 'base64'
. If encoding
is provided a string is\nreturned; otherwise a [Buffer
][] is returned.
Returns the Diffie-Hellman private key in the specified encoding
,\nwhich can be 'binary'
, 'hex'
, or 'base64'
. If encoding
is provided a\nstring is returned; otherwise a [Buffer
][] is returned.
Returns the Diffie-Hellman public key in the specified encoding
, which\ncan be 'binary'
, 'hex'
, or 'base64'
. If encoding
is provided a\nstring is returned; otherwise a [Buffer
][] is returned.
Sets the Diffie-Hellman private key. If the encoding
argument is provided\nand is either 'binary'
, 'hex'
, or 'base64'
, private_key
is expected\nto be a string. If no encoding
is provided, private_key
is expected\nto be a [Buffer
][].
Sets the Diffie-Hellman public key. If the encoding
argument is provided\nand is either 'binary'
, 'hex'
or 'base64'
, public_key
is expected\nto be a string. If no encoding
is provided, public_key
is expected\nto be a [Buffer
][].
A bit field containing any warnings and/or errors resulting from a check\nperformed during initialization of the DiffieHellman
object.
The following values are valid for this property (as defined in constants
\nmodule):
DH_CHECK_P_NOT_SAFE_PRIME
DH_CHECK_P_NOT_PRIME
DH_UNABLE_TO_CHECK_GENERATOR
DH_NOT_SUITABLE_GENERATOR
The ECDH
class is a utility for creating Elliptic Curve Diffie-Hellman (ECDH)\nkey exchanges.
Instances of the ECDH
class can be created using the\n[crypto.createECDH()
][] function.
const crypto = require('crypto');\nconst assert = require('assert');\n\n// Generate Alice's keys...\nconst alice = crypto.createECDH('secp521r1');\nconst alice_key = alice.generateKeys();\n\n// Generate Bob's keys...\nconst bob = crypto.createECDH('secp521r1');\nconst bob_key = bob.generateKeys();\n\n// Exchange and generate the secret...\nconst alice_secret = alice.computeSecret(bob_key);\nconst bob_secret = bob.computeSecret(alice_key);\n\nassert(alice_secret, bob_secret);\n // OK\n
\n",
"methods": [
{
"textRaw": "ecdh.computeSecret(other_public_key[, input_encoding][, output_encoding])",
"type": "method",
"name": "computeSecret",
"desc": "Computes the shared secret using other_public_key
as the other\nparty's public key and returns the computed shared secret. The supplied\nkey is interpreted using specified input_encoding
, and the returned secret\nis encoded using the specified output_encoding
. Encodings can be\n'binary'
, 'hex'
, or 'base64'
. If the input_encoding
is not\nprovided, other_public_key
is expected to be a [Buffer
][].
If output_encoding
is given a string will be returned; otherwise a\n[Buffer
][] is returned.
Generates private and public EC Diffie-Hellman key values, and returns\nthe public key in the specified format
and encoding
. This key should be\ntransferred to the other party.
The format
arguments specifies point encoding and can be 'compressed'
,\n'uncompressed'
, or 'hybrid'
. If format
is not specified, the point will\nbe returned in 'uncompressed'
format.
The encoding
argument can be 'binary'
, 'hex'
, or 'base64'
. If\nencoding
is provided a string is returned; otherwise a [Buffer
][]\nis returned.
Returns the EC Diffie-Hellman private key in the specified encoding
,\nwhich can be 'binary'
, 'hex'
, or 'base64'
. If encoding
is provided\na string is returned; otherwise a [Buffer
][] is returned.
Returns the EC Diffie-Hellman public key in the specified encoding
and\nformat
.
The format
argument specifies point encoding and can be 'compressed'
,\n'uncompressed'
, or 'hybrid'
. If format
is not specified the point will be\nreturned in 'uncompressed'
format.
The encoding
argument can be 'binary'
, 'hex'
, or 'base64'
. If\nencoding
is specified, a string is returned; otherwise a [Buffer
][] is\nreturned.
Sets the EC Diffie-Hellman private key. The encoding
can be 'binary'
,\n'hex'
or 'base64'
. If encoding
is provided, private_key
is expected\nto be a string; otherwise private_key
is expected to be a [Buffer
][]. If\nprivate_key
is not valid for the curve specified when the ECDH
object was\ncreated, an error is thrown. Upon setting the private key, the associated\npublic point (key) is also generated and set in the ECDH object.
Sets the EC Diffie-Hellman public key. Key encoding can be 'binary'
,\n'hex'
or 'base64'
. If encoding
is provided public_key
is expected to\nbe a string; otherwise a [Buffer
][] is expected.
Note that there is not normally a reason to call this method because ECDH
\nonly requires a private key and the other party's public key to compute the\nshared secret. Typically either [ecdh.generateKeys()
][] or\n[ecdh.setPrivateKey()
][] will be called. The [ecdh.setPrivateKey()
][] method\nattempts to generate the public point/key associated with the private key being\nset.
Example (obtaining a shared secret):
\nconst crypto = require('crypto');\nconst alice = crypto.createECDH('secp256k1');\nconst bob = crypto.createECDH('secp256k1');\n\n// Note: This is a shortcut way to specify one of Alice's previous private\n// keys. It would be unwise to use such a predictable private key in a real\n// application.\nalice.setPrivateKey(\n crypto.createHash('sha256').update('alice', 'utf8').digest()\n);\n\n// Bob uses a newly generated cryptographically strong\n// pseudorandom key pair bob.generateKeys();\n\nconst alice_secret = alice.computeSecret(bob.getPublicKey(), null, 'hex');\nconst bob_secret = bob.computeSecret(alice.getPublicKey(), null, 'hex');\n\n// alice_secret and bob_secret should be the same shared secret value\nconsole.log(alice_secret === bob_secret);\n
\n",
"signatures": [
{
"params": [
{
"name": "public_key"
},
{
"name": "encoding",
"optional": true
}
]
}
]
}
]
},
{
"textRaw": "Class: Hash",
"type": "class",
"name": "Hash",
"desc": "The Hash
class is a utility for creating hash digests of data. It can be\nused in one of two ways:
hash.update()
][] and [hash.digest()
][] methods to produce the\ncomputed hash.The [crypto.createHash()
][] method is used to create Hash
instances. Hash
\nobjects are not to be created directly using the new
keyword.
Example: Using Hash
objects as streams:
const crypto = require('crypto');\nconst hash = crypto.createHash('sha256');\n\nhash.on('readable', () => {\n var data = hash.read();\n if (data)\n console.log(data.toString('hex'));\n // Prints:\n // 6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50\n});\n\nhash.write('some data to hash');\nhash.end();\n
\nExample: Using Hash
and piped streams:
const crypto = require('crypto');\nconst fs = require('fs');\nconst hash = crypto.createHash('sha256');\n\nconst input = fs.createReadStream('test.js');\ninput.pipe(hash).pipe(process.stdout);\n
\nExample: Using the [hash.update()
][] and [hash.digest()
][] methods:
const crypto = require('crypto');\nconst hash = crypto.createHash('sha256');\n\nhash.update('some data to hash');\nconsole.log(hash.digest('hex'));\n // Prints:\n // 6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50\n
\n",
"methods": [
{
"textRaw": "hash.digest([encoding])",
"type": "method",
"name": "digest",
"desc": "Calculates the digest of all of the data passed to be hashed (using the\n[hash.update()
][] method). The encoding
can be 'hex'
, 'binary'
or\n'base64'
. If encoding
is provided a string will be returned; otherwise\na [Buffer
][] is returned.
The Hash
object can not be used again after hash.digest()
method has been\ncalled. Multiple calls will cause an error to be thrown.
Updates the hash content with the given data
, the encoding of which\nis given in input_encoding
and can be 'utf8'
, 'ascii'
or\n'binary'
. If encoding
is not provided, and the data
is a string, an\nencoding of 'utf8'
is enforced. If data
is a [Buffer
][] then\ninput_encoding
is ignored.
This can be called many times with new data as it is streamed.
\n", "signatures": [ { "params": [ { "name": "data" }, { "name": "input_encoding", "optional": true } ] } ] } ] }, { "textRaw": "Class: Hmac", "type": "class", "name": "Hmac", "desc": "The Hmac
Class is a utility for creating cryptographic HMAC digests. It can\nbe used in one of two ways:
hmac.update()
][] and [hmac.digest()
][] methods to produce the\ncomputed HMAC digest.The [crypto.createHmac()
][] method is used to create Hmac
instances. Hmac
\nobjects are not to be created directly using the new
keyword.
Example: Using Hmac
objects as streams:
const crypto = require('crypto');\nconst hmac = crypto.createHmac('sha256', 'a secret');\n\nhmac.on('readable', () => {\n var data = hmac.read();\n if (data)\n console.log(data.toString('hex'));\n // Prints:\n // 7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e\n});\n\nhmac.write('some data to hash');\nhmac.end();\n
\nExample: Using Hmac
and piped streams:
const crypto = require('crypto');\nconst fs = require('fs');\nconst hmac = crypto.createHmac('sha256', 'a secret');\n\nconst input = fs.createReadStream('test.js');\ninput.pipe(hmac).pipe(process.stdout);\n
\nExample: Using the [hmac.update()
][] and [hmac.digest()
][] methods:
const crypto = require('crypto');\nconst hmac = crypto.createHmac('sha256', 'a secret');\n\nhmac.update('some data to hash');\nconsole.log(hmac.digest('hex'));\n // Prints:\n // 7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e\n
\n",
"methods": [
{
"textRaw": "hmac.digest([encoding])",
"type": "method",
"name": "digest",
"desc": "Calculates the HMAC digest of all of the data passed using [hmac.update()
][].\nThe encoding
can be 'hex'
, 'binary'
or 'base64'
. If encoding
is\nprovided a string is returned; otherwise a [Buffer
][] is returned;
The Hmac
object can not be used again after hmac.digest()
has been\ncalled. Multiple calls to hmac.digest()
will result in an error being thrown.
Updates the Hmac
content with the given data
, the encoding of which\nis given in input_encoding
and can be 'utf8'
, 'ascii'
or\n'binary'
. If encoding
is not provided, and the data
is a string, an\nencoding of 'utf8'
is enforced. If data
is a [Buffer
][] then\ninput_encoding
is ignored.
This can be called many times with new data as it is streamed.
\n", "signatures": [ { "params": [ { "name": "data" }, { "name": "input_encoding", "optional": true } ] } ] } ] }, { "textRaw": "Class: Sign", "type": "class", "name": "Sign", "desc": "The Sign
Class is a utility for generating signatures. It can be used in one\nof two ways:
sign.sign()
][] method is used to generate and return the signature, orsign.update()
][] and [sign.sign()
][] methods to produce the\nsignature.The [crypto.createSign()
][] method is used to create Sign
instances. Sign
\nobjects are not to be created directly using the new
keyword.
Example: Using Sign
objects as streams:
const crypto = require('crypto');\nconst sign = crypto.createSign('RSA-SHA256');\n\nsign.write('some data to sign');\nsign.end();\n\nconst private_key = getPrivateKeySomehow();\nconsole.log(sign.sign(private_key, 'hex'));\n // Prints the calculated signature\n
\nExample: Using the [sign.update()
][] and [sign.sign()
][] methods:
const crypto = require('crypto');\nconst sign = crypto.createSign('RSA-SHA256');\n\nsign.update('some data to sign');\n\nconst private_key = getPrivateKeySomehow();\nconsole.log(sign.sign(private_key, 'hex'));\n // Prints the calculated signature\n
\nA Sign
instance can also be created by just passing in the digest\nalgorithm name, in which case OpenSSL will infer the full signature algorithm\nfrom the type of the PEM-formatted private key, including algorithms that\ndo not have directly exposed name constants, e.g. 'ecdsa-with-SHA256'.
Example: signing using ECDSA with SHA256
\nconst crypto = require('crypto');\nconst sign = crypto.createSign('sha256');\n\nsign.update('some data to sign');\n\nconst private_key = '-----BEGIN EC PRIVATE KEY-----\\n' +\n 'MHcCAQEEIF+jnWY1D5kbVYDNvxxo/Y+ku2uJPDwS0r/VuPZQrjjVoAoGCCqGSM49\\n' +\n 'AwEHoUQDQgAEurOxfSxmqIRYzJVagdZfMMSjRNNhB8i3mXyIMq704m2m52FdfKZ2\\n' +\n 'pQhByd5eyj3lgZ7m7jbchtdgyOF8Io/1ng==\\n' +\n '-----END EC PRIVATE KEY-----\\n';\n\nconsole.log(sign.sign(private_key).toString('hex'));\n
\n",
"methods": [
{
"textRaw": "sign.sign(private_key[, output_format])",
"type": "method",
"name": "sign",
"desc": "Calculates the signature on all the data passed through using either\n[sign.update()
][] or [sign.write()
][stream-writable-write].
The private_key
argument can be an object or a string. If private_key
is a\nstring, it is treated as a raw key with no passphrase. If private_key
is an\nobject, it is interpreted as a hash containing two properties:
key
: {String} - PEM encoded private keypassphrase
: {String} - passphrase for the private keyThe output_format
can specify one of 'binary'
, 'hex'
or 'base64'
. If\noutput_format
is provided a string is returned; otherwise a [Buffer
][] is\nreturned.
The Sign
object can not be again used after sign.sign()
method has been\ncalled. Multiple calls to sign.sign()
will result in an error being thrown.
Updates the Sign
content with the given data
, the encoding of which\nis given in input_encoding
and can be 'utf8'
, 'ascii'
or\n'binary'
. If encoding
is not provided, and the data
is a string, an\nencoding of 'utf8'
is enforced. If data
is a [Buffer
][] then\ninput_encoding
is ignored.
This can be called many times with new data as it is streamed.
\n", "signatures": [ { "params": [ { "name": "data" }, { "name": "input_encoding", "optional": true } ] } ] } ] }, { "textRaw": "Class: Verify", "type": "class", "name": "Verify", "desc": "The Verify
class is a utility for verifying signatures. It can be used in one\nof two ways:
Using the [verify.update()
][] and [verify.verify()
][] methods to verify\nthe signature.
The [crypto.createSign()
][] method is used to create Sign
instances.\nSign
objects are not to be created directly using the new
keyword.
Example: Using Verify
objects as streams:
const crypto = require('crypto');\nconst verify = crypto.createVerify('RSA-SHA256');\n\nverify.write('some data to sign');\nverify.end();\n\nconst public_key = getPublicKeySomehow();\nconst signature = getSignatureToVerify();\nconsole.log(verify.verify(public_key, signature));\n // Prints true or false\n
\nExample: Using the [verify.update()
][] and [verify.verify()
][] methods:
const crypto = require('crypto');\nconst verify = crypto.createVerify('RSA-SHA256');\n\nverify.update('some data to sign');\n\nconst public_key = getPublicKeySomehow();\nconst signature = getSignatureToVerify();\nconsole.log(verify.verify(public_key, signature));\n // Prints true or false\n
\n",
"methods": [
{
"textRaw": "verifier.update(data[, input_encoding])",
"type": "method",
"name": "update",
"desc": "Updates the Verify
content with the given data
, the encoding of which\nis given in input_encoding
and can be 'utf8'
, 'ascii'
or\n'binary'
. If encoding
is not provided, and the data
is a string, an\nencoding of 'utf8'
is enforced. If data
is a [Buffer
][] then\ninput_encoding
is ignored.
This can be called many times with new data as it is streamed.
\n", "signatures": [ { "params": [ { "name": "data" }, { "name": "input_encoding", "optional": true } ] } ] }, { "textRaw": "verifier.verify(object, signature[, signature_format])", "type": "method", "name": "verify", "desc": "Verifies the provided data using the given object
and signature
.\nThe object
argument is a string containing a PEM encoded object, which can be\none an RSA public key, a DSA public key, or an X.509 certificate.\nThe signature
argument is the previously calculated signature for the data, in\nthe signature_format
which can be 'binary'
, 'hex'
or 'base64'
.\nIf a signature_format
is specified, the signature
is expected to be a\nstring; otherwise signature
is expected to be a [Buffer
][].
Returns true
or false
depending on the validity of the signature for\nthe data and public key.
The verifier
object can not be used again after verify.verify()
has been\ncalled. Multiple calls to verify.verify()
will result in an error being\nthrown.
Returns an object containing commonly used constants for crypto and security\nrelated operations. The specific constants currently defined are described in\n[Crypto Constants][].
\n", "properties": [ { "textRaw": "crypto.DEFAULT_ENCODING", "name": "DEFAULT_ENCODING", "desc": "The default encoding to use for functions that can take either strings\nor [buffers][Buffer
]. The default value is 'buffer'
, which makes methods\ndefault to [Buffer
][] objects.
The crypto.DEFAULT_ENCODING
mechanism is provided for backwards compatibility\nwith legacy programs that expect 'binary'
to be the default encoding.
New applications should expect the default to be 'buffer'
. This property may\nbecome deprecated in a future Node.js release.
Property for checking and controlling whether a FIPS compliant crypto provider is\ncurrently in use. Setting to true requires a FIPS build of Node.js.
\n" } ], "methods": [ { "textRaw": "crypto.createCipher(algorithm, password)", "type": "method", "name": "createCipher", "desc": "Creates and returns a Cipher
object that uses the given algorithm
and\npassword
.
The algorithm
is dependent on OpenSSL, examples are 'aes192'
, etc. On\nrecent OpenSSL releases, openssl list-cipher-algorithms
will display the\navailable cipher algorithms.
The password
is used to derive the cipher key and initialization vector (IV).\nThe value must be either a 'binary'
encoded string or a [Buffer
][].
The implementation of crypto.createCipher()
derives keys using the OpenSSL\nfunction [EVP_BytesToKey
][] with the digest algorithm set to MD5, one\niteration, and no salt. The lack of salt allows dictionary attacks as the same\npassword always creates the same key. The low iteration count and\nnon-cryptographically secure hash algorithm allow passwords to be tested very\nrapidly.
In line with OpenSSL's recommendation to use pbkdf2 instead of\n[EVP_BytesToKey
][] it is recommended that developers derive a key and IV on\ntheir own using [crypto.pbkdf2()
][] and to use [crypto.createCipheriv()
][]\nto create the Cipher
object.
Creates and returns a Cipher
object, with the given algorithm
, key
and\ninitialization vector (iv
).
The algorithm
is dependent on OpenSSL, examples are 'aes192'
, etc. On\nrecent OpenSSL releases, openssl list-cipher-algorithms
will display the\navailable cipher algorithms.
The key
is the raw key used by the algorithm
and iv
is an\n[initialization vector][]. Both arguments must be 'binary'
encoded strings or\n[buffers][Buffer
].
The crypto.createCredentials()
method is a deprecated alias for creating\nand returning a tls.SecureContext
object. The crypto.createCredentials()
\nmethod should not be used.
The optional details
argument is a hash object with keys:
pfx
: {String|Buffer} - PFX or PKCS12 encoded private\nkey, certificate and CA certificateskey
: {String} - PEM encoded private keypassphrase
: {String} - passphrase for the private key or PFXcert
: {String} - PEM encoded certificateca
: {String|Array} - Either a string or array of strings of PEM encoded CA\ncertificates to trust.crl
: {String|Array} - Either a string or array of strings of PEM encoded CRLs\n(Certificate Revocation List)ciphers
: {String} using the [OpenSSL cipher list format][] describing the\ncipher algorithms to use or exclude.If no 'ca' details are given, Node.js will use Mozilla's default\n[publicly trusted list of CAs][].
\n", "signatures": [ { "params": [ { "name": "details" } ] } ] }, { "textRaw": "crypto.createDecipher(algorithm, password)", "type": "method", "name": "createDecipher", "desc": "Creates and returns a Decipher
object that uses the given algorithm
and\npassword
(key).
The implementation of crypto.createDecipher()
derives keys using the OpenSSL\nfunction [EVP_BytesToKey
][] with the digest algorithm set to MD5, one\niteration, and no salt. The lack of salt allows dictionary attacks as the same\npassword always creates the same key. The low iteration count and\nnon-cryptographically secure hash algorithm allow passwords to be tested very\nrapidly.
In line with OpenSSL's recommendation to use pbkdf2 instead of\n[EVP_BytesToKey
][] it is recommended that developers derive a key and IV on\ntheir own using [crypto.pbkdf2()
][] and to use [crypto.createDecipheriv()
][]\nto create the Decipher
object.
Creates and returns a Decipher
object that uses the given algorithm
, key
\nand initialization vector (iv
).
The algorithm
is dependent on OpenSSL, examples are 'aes192'
, etc. On\nrecent OpenSSL releases, openssl list-cipher-algorithms
will display the\navailable cipher algorithms.
The key
is the raw key used by the algorithm
and iv
is an\n[initialization vector][]. Both arguments must be 'binary'
encoded strings or\n[buffers][Buffer
].
Creates a DiffieHellman
key exchange object using the supplied prime
and an\noptional specific generator
.
The generator
argument can be a number, string, or [Buffer
][]. If\ngenerator
is not specified, the value 2
is used.
The prime_encoding
and generator_encoding
arguments can be 'binary'
,\n'hex'
, or 'base64'
.
If prime_encoding
is specified, prime
is expected to be a string; otherwise\na [Buffer
][] is expected.
If generator_encoding
is specified, generator
is expected to be a string;\notherwise either a number or [Buffer
][] is expected.
Creates a DiffieHellman
key exchange object and generates a prime of\nprime_length
bits using an optional specific numeric generator
.\nIf generator
is not specified, the value 2
is used.
Creates an Elliptic Curve Diffie-Hellman (ECDH
) key exchange object using a\npredefined curve specified by the curve_name
string. Use\n[crypto.getCurves()
][] to obtain a list of available curve names. On recent\nOpenSSL releases, openssl ecparam -list_curves
will also display the name\nand description of each available elliptic curve.
Creates and returns a Hash
object that can be used to generate hash digests\nusing the given algorithm
.
The algorithm
is dependent on the available algorithms supported by the\nversion of OpenSSL on the platform. Examples are 'sha256'
, 'sha512'
, etc.\nOn recent releases of OpenSSL, openssl list-message-digest-algorithms
will\ndisplay the available digest algorithms.
Example: generating the sha256 sum of a file
\nconst filename = process.argv[2];\nconst crypto = require('crypto');\nconst fs = require('fs');\n\nconst hash = crypto.createHash('sha256');\n\nconst input = fs.createReadStream(filename);\ninput.on('readable', () => {\n var data = input.read();\n if (data)\n hash.update(data);\n else {\n console.log(`${hash.digest('hex')} ${filename}`);\n }\n});\n
\n",
"signatures": [
{
"params": [
{
"name": "algorithm"
}
]
}
]
},
{
"textRaw": "crypto.createHmac(algorithm, key)",
"type": "method",
"name": "createHmac",
"desc": "Creates and returns an Hmac
object that uses the given algorithm
and key
.
The algorithm
is dependent on the available algorithms supported by the\nversion of OpenSSL on the platform. Examples are 'sha256'
, 'sha512'
, etc.\nOn recent releases of OpenSSL, openssl list-message-digest-algorithms
will\ndisplay the available digest algorithms.
The key
is the HMAC key used to generate the cryptographic HMAC hash.
Example: generating the sha256 HMAC of a file
\nconst filename = process.argv[2];\nconst crypto = require('crypto');\nconst fs = require('fs');\n\nconst hmac = crypto.createHmac('sha256', 'a secret');\n\nconst input = fs.createReadStream(filename);\ninput.on('readable', () => {\n var data = input.read();\n if (data)\n hmac.update(data);\n else {\n console.log(`${hmac.digest('hex')} ${filename}`);\n }\n});\n
\n",
"signatures": [
{
"params": [
{
"name": "algorithm"
},
{
"name": "key"
}
]
}
]
},
{
"textRaw": "crypto.createSign(algorithm)",
"type": "method",
"name": "createSign",
"desc": "Creates and returns a Sign
object that uses the given algorithm
. On\nrecent OpenSSL releases, openssl list-public-key-algorithms
will\ndisplay the available signing algorithms. One example is 'RSA-SHA256'
.
Creates and returns a Verify
object that uses the given algorithm. On\nrecent OpenSSL releases, openssl list-public-key-algorithms
will\ndisplay the available signing algorithms. One example is 'RSA-SHA256'
.
Returns an array with the names of the supported cipher algorithms.
\nExample:
\nconst ciphers = crypto.getCiphers();\nconsole.log(ciphers); // ['aes-128-cbc', 'aes-128-ccm', ...]\n
\n",
"signatures": [
{
"params": []
}
]
},
{
"textRaw": "crypto.getCurves()",
"type": "method",
"name": "getCurves",
"desc": "Returns an array with the names of the supported elliptic curves.
\nExample:
\nconst curves = crypto.getCurves();\nconsole.log(curves); // ['secp256k1', 'secp384r1', ...]\n
\n",
"signatures": [
{
"params": []
}
]
},
{
"textRaw": "crypto.getDiffieHellman(group_name)",
"type": "method",
"name": "getDiffieHellman",
"desc": "Creates a predefined DiffieHellman
key exchange object. The\nsupported groups are: 'modp1'
, 'modp2'
, 'modp5'
(defined in\n[RFC 2412][], but see [Caveats][]) and 'modp14'
, 'modp15'
,\n'modp16'
, 'modp17'
, 'modp18'
(defined in [RFC 3526][]). The\nreturned object mimics the interface of objects created by\n[crypto.createDiffieHellman()
][], but will not allow changing\nthe keys (with [diffieHellman.setPublicKey()
][] for example). The\nadvantage of using this method is that the parties do not have to\ngenerate nor exchange a group modulus beforehand, saving both processor\nand communication time.
Example (obtaining a shared secret):
\nconst crypto = require('crypto');\nconst alice = crypto.getDiffieHellman('modp14');\nconst bob = crypto.getDiffieHellman('modp14');\n\nalice.generateKeys();\nbob.generateKeys();\n\nconst alice_secret = alice.computeSecret(bob.getPublicKey(), null, 'hex');\nconst bob_secret = bob.computeSecret(alice.getPublicKey(), null, 'hex');\n\n/* alice_secret and bob_secret should be the same */\nconsole.log(alice_secret == bob_secret);\n
\n",
"signatures": [
{
"params": [
{
"name": "group_name"
}
]
}
]
},
{
"textRaw": "crypto.getHashes()",
"type": "method",
"name": "getHashes",
"desc": "Returns an array with the names of the supported hash algorithms.
\nExample:
\nconst hashes = crypto.getHashes();\nconsole.log(hashes); // ['sha', 'sha1', 'sha1WithRSAEncryption', ...]\n
\n",
"signatures": [
{
"params": []
}
]
},
{
"textRaw": "crypto.pbkdf2(password, salt, iterations, keylen, digest, callback)",
"type": "method",
"name": "pbkdf2",
"desc": "Provides an asynchronous Password-Based Key Derivation Function 2 (PBKDF2)\nimplementation. A selected HMAC digest algorithm specified by digest
is\napplied to derive a key of the requested byte length (keylen
) from the\npassword
, salt
and iterations
.
The supplied callback
function is called with two arguments: err
and\nderivedKey
. If an error occurs, err
will be set; otherwise err
will be\nnull. The successfully generated derivedKey
will be passed as a [Buffer
][].
The iterations
argument must be a number set as high as possible. The\nhigher the number of iterations, the more secure the derived key will be,\nbut will take a longer amount of time to complete.
The salt
should also be as unique as possible. It is recommended that the\nsalts are random and their lengths are greater than 16 bytes. See\n[NIST SP 800-132][] for details.
Example:
\nconst crypto = require('crypto');\ncrypto.pbkdf2('secret', 'salt', 100000, 512, 'sha512', (err, key) => {\n if (err) throw err;\n console.log(key.toString('hex')); // 'c5e478d...1469e50'\n});\n
\nAn array of supported digest functions can be retrieved using\n[crypto.getHashes()
][].
Provides a synchronous Password-Based Key Derivation Function 2 (PBKDF2)\nimplementation. A selected HMAC digest algorithm specified by digest
is\napplied to derive a key of the requested byte length (keylen
) from the\npassword
, salt
and iterations
.
If an error occurs an Error will be thrown, otherwise the derived key will be\nreturned as a [Buffer
][].
The iterations
argument must be a number set as high as possible. The\nhigher the number of iterations, the more secure the derived key will be,\nbut will take a longer amount of time to complete.
The salt
should also be as unique as possible. It is recommended that the\nsalts are random and their lengths are greater than 16 bytes. See\n[NIST SP 800-132][] for details.
Example:
\nconst crypto = require('crypto');\nconst key = crypto.pbkdf2Sync('secret', 'salt', 100000, 512, 'sha512');\nconsole.log(key.toString('hex')); // 'c5e478d...1469e50'\n
\nAn array of supported digest functions can be retrieved using\n[crypto.getHashes()
][].
Decrypts buffer
with private_key
.
private_key
can be an object or a string. If private_key
is a string, it is\ntreated as the key with no passphrase and will use RSA_PKCS1_OAEP_PADDING
.\nIf private_key
is an object, it is interpreted as a hash object with the\nkeys:
key
: {String} - PEM encoded private keypassphrase
: {String} - Optional passphrase for the private keypadding
: An optional padding value, one of the following:crypto.constants.RSA_NO_PADDING
crypto.constants.RSA_PKCS1_PADDING
crypto.constants.RSA_PKCS1_OAEP_PADDING
All paddings are defined in crypto.constants
.
Encrypts buffer
with private_key
.
private_key
can be an object or a string. If private_key
is a string, it is\ntreated as the key with no passphrase and will use RSA_PKCS1_PADDING
.\nIf private_key
is an object, it is interpreted as a hash object with the\nkeys:
key
: {String} - PEM encoded private keypassphrase
: {String} - Optional passphrase for the private keypadding
: An optional padding value, one of the following:crypto.constants.RSA_NO_PADDING
crypto.constants.RSA_PKCS1_PADDING
crypto.constants.RSA_PKCS1_OAEP_PADDING
All paddings are defined in crypto.constants
.
Decrypts buffer
with public_key
.
public_key
can be an object or a string. If public_key
is a string, it is\ntreated as the key with no passphrase and will use RSA_PKCS1_PADDING
.\nIf public_key
is an object, it is interpreted as a hash object with the\nkeys:
key
: {String} - PEM encoded public keypassphrase
: {String} - Optional passphrase for the private keypadding
: An optional padding value, one of the following:crypto.constants.RSA_NO_PADDING
crypto.constants.RSA_PKCS1_PADDING
crypto.constants.RSA_PKCS1_OAEP_PADDING
Because RSA public keys can be derived from private keys, a private key may\nbe passed instead of a public key.
\nAll paddings are defined in crypto.constants
.
Encrypts buffer
with public_key
.
public_key
can be an object or a string. If public_key
is a string, it is\ntreated as the key with no passphrase and will use RSA_PKCS1_OAEP_PADDING
.\nIf public_key
is an object, it is interpreted as a hash object with the\nkeys:
key
: {String} - PEM encoded public keypassphrase
: {String} - Optional passphrase for the private keypadding
: An optional padding value, one of the following:crypto.constants.RSA_NO_PADDING
crypto.constants.RSA_PKCS1_PADDING
crypto.constants.RSA_PKCS1_OAEP_PADDING
Because RSA public keys can be derived from private keys, a private key may\nbe passed instead of a public key.
\nAll paddings are defined in crypto.constants
.
Generates cryptographically strong pseudo-random data. The size
argument\nis a number indicating the number of bytes to generate.
If a callback
function is provided, the bytes are generated asynchronously\nand the callback
function is invoked with two arguments: err
and buf
.\nIf an error occurs, err
will be an Error object; otherwise it is null. The\nbuf
argument is a [Buffer
][] containing the generated bytes.
// Asynchronous\nconst crypto = require('crypto');\ncrypto.randomBytes(256, (err, buf) => {\n if (err) throw err;\n console.log(`${buf.length} bytes of random data: ${buf.toString('hex')}`);\n});\n
\nIf the callback
function is not provided, the random bytes are generated\nsynchronously and returned as a [Buffer
][]. An error will be thrown if\nthere is a problem generating the bytes.
// Synchronous\nconst buf = crypto.randomBytes(256);\nconsole.log(\n `${buf.length} bytes of random data: ${buf.toString('hex')}`);\n
\nThe crypto.randomBytes()
method will block until there is sufficient entropy.\nThis should normally never take longer than a few milliseconds. The only time\nwhen generating the random bytes may conceivably block for a longer period of\ntime is right after boot, when the whole system is still low on entropy.
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
\nis a bit field taking one of or a mix of the following flags (defined in\ncrypto.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
Returns an object containing commonly used constants for crypto and security\nrelated operations. The specific constants currently defined are described in\n[Crypto Constants][].
\n", "properties": [ { "textRaw": "crypto.DEFAULT_ENCODING", "name": "DEFAULT_ENCODING", "desc": "The default encoding to use for functions that can take either strings\nor [buffers][Buffer
]. The default value is 'buffer'
, which makes methods\ndefault to [Buffer
][] objects.
The crypto.DEFAULT_ENCODING
mechanism is provided for backwards compatibility\nwith legacy programs that expect 'binary'
to be the default encoding.
New applications should expect the default to be 'buffer'
. This property may\nbecome deprecated in a future Node.js release.
Property for checking and controlling whether a FIPS compliant crypto provider is\ncurrently in use. Setting to true requires a FIPS build of Node.js.
\n" } ], "methods": [ { "textRaw": "crypto.createCipher(algorithm, password)", "type": "method", "name": "createCipher", "desc": "Creates and returns a Cipher
object that uses the given algorithm
and\npassword
.
The algorithm
is dependent on OpenSSL, examples are 'aes192'
, etc. On\nrecent OpenSSL releases, openssl list-cipher-algorithms
will display the\navailable cipher algorithms.
The password
is used to derive the cipher key and initialization vector (IV).\nThe value must be either a 'binary'
encoded string or a [Buffer
][].
The implementation of crypto.createCipher()
derives keys using the OpenSSL\nfunction [EVP_BytesToKey
][] with the digest algorithm set to MD5, one\niteration, and no salt. The lack of salt allows dictionary attacks as the same\npassword always creates the same key. The low iteration count and\nnon-cryptographically secure hash algorithm allow passwords to be tested very\nrapidly.
In line with OpenSSL's recommendation to use pbkdf2 instead of\n[EVP_BytesToKey
][] it is recommended that developers derive a key and IV on\ntheir own using [crypto.pbkdf2()
][] and to use [crypto.createCipheriv()
][]\nto create the Cipher
object.
Creates and returns a Cipher
object, with the given algorithm
, key
and\ninitialization vector (iv
).
The algorithm
is dependent on OpenSSL, examples are 'aes192'
, etc. On\nrecent OpenSSL releases, openssl list-cipher-algorithms
will display the\navailable cipher algorithms.
The key
is the raw key used by the algorithm
and iv
is an\n[initialization vector][]. Both arguments must be 'binary'
encoded strings or\n[buffers][Buffer
].
The crypto.createCredentials()
method is a deprecated alias for creating\nand returning a tls.SecureContext
object. The crypto.createCredentials()
\nmethod should not be used.
The optional details
argument is a hash object with keys:
pfx
: {String|Buffer} - PFX or PKCS12 encoded private\nkey, certificate and CA certificateskey
: {String} - PEM encoded private keypassphrase
: {String} - passphrase for the private key or PFXcert
: {String} - PEM encoded certificateca
: {String|Array} - Either a string or array of strings of PEM encoded CA\ncertificates to trust.crl
: {String|Array} - Either a string or array of strings of PEM encoded CRLs\n(Certificate Revocation List)ciphers
: {String} using the [OpenSSL cipher list format][] describing the\ncipher algorithms to use or exclude.If no 'ca' details are given, Node.js will use Mozilla's default\n[publicly trusted list of CAs][].
\n", "signatures": [ { "params": [ { "name": "details" } ] } ] }, { "textRaw": "crypto.createDecipher(algorithm, password)", "type": "method", "name": "createDecipher", "desc": "Creates and returns a Decipher
object that uses the given algorithm
and\npassword
(key).
The implementation of crypto.createDecipher()
derives keys using the OpenSSL\nfunction [EVP_BytesToKey
][] with the digest algorithm set to MD5, one\niteration, and no salt. The lack of salt allows dictionary attacks as the same\npassword always creates the same key. The low iteration count and\nnon-cryptographically secure hash algorithm allow passwords to be tested very\nrapidly.
In line with OpenSSL's recommendation to use pbkdf2 instead of\n[EVP_BytesToKey
][] it is recommended that developers derive a key and IV on\ntheir own using [crypto.pbkdf2()
][] and to use [crypto.createDecipheriv()
][]\nto create the Decipher
object.
Creates and returns a Decipher
object that uses the given algorithm
, key
\nand initialization vector (iv
).
The algorithm
is dependent on OpenSSL, examples are 'aes192'
, etc. On\nrecent OpenSSL releases, openssl list-cipher-algorithms
will display the\navailable cipher algorithms.
The key
is the raw key used by the algorithm
and iv
is an\n[initialization vector][]. Both arguments must be 'binary'
encoded strings or\n[buffers][Buffer
].
Creates a DiffieHellman
key exchange object using the supplied prime
and an\noptional specific generator
.
The generator
argument can be a number, string, or [Buffer
][]. If\ngenerator
is not specified, the value 2
is used.
The prime_encoding
and generator_encoding
arguments can be 'binary'
,\n'hex'
, or 'base64'
.
If prime_encoding
is specified, prime
is expected to be a string; otherwise\na [Buffer
][] is expected.
If generator_encoding
is specified, generator
is expected to be a string;\notherwise either a number or [Buffer
][] is expected.
Creates a DiffieHellman
key exchange object and generates a prime of\nprime_length
bits using an optional specific numeric generator
.\nIf generator
is not specified, the value 2
is used.
Creates an Elliptic Curve Diffie-Hellman (ECDH
) key exchange object using a\npredefined curve specified by the curve_name
string. Use\n[crypto.getCurves()
][] to obtain a list of available curve names. On recent\nOpenSSL releases, openssl ecparam -list_curves
will also display the name\nand description of each available elliptic curve.
Creates and returns a Hash
object that can be used to generate hash digests\nusing the given algorithm
.
The algorithm
is dependent on the available algorithms supported by the\nversion of OpenSSL on the platform. Examples are 'sha256'
, 'sha512'
, etc.\nOn recent releases of OpenSSL, openssl list-message-digest-algorithms
will\ndisplay the available digest algorithms.
Example: generating the sha256 sum of a file
\nconst filename = process.argv[2];\nconst crypto = require('crypto');\nconst fs = require('fs');\n\nconst hash = crypto.createHash('sha256');\n\nconst input = fs.createReadStream(filename);\ninput.on('readable', () => {\n var data = input.read();\n if (data)\n hash.update(data);\n else {\n console.log(`${hash.digest('hex')} ${filename}`);\n }\n});\n
\n",
"signatures": [
{
"params": [
{
"name": "algorithm"
}
]
}
]
},
{
"textRaw": "crypto.createHmac(algorithm, key)",
"type": "method",
"name": "createHmac",
"desc": "Creates and returns an Hmac
object that uses the given algorithm
and key
.
The algorithm
is dependent on the available algorithms supported by the\nversion of OpenSSL on the platform. Examples are 'sha256'
, 'sha512'
, etc.\nOn recent releases of OpenSSL, openssl list-message-digest-algorithms
will\ndisplay the available digest algorithms.
The key
is the HMAC key used to generate the cryptographic HMAC hash.
Example: generating the sha256 HMAC of a file
\nconst filename = process.argv[2];\nconst crypto = require('crypto');\nconst fs = require('fs');\n\nconst hmac = crypto.createHmac('sha256', 'a secret');\n\nconst input = fs.createReadStream(filename);\ninput.on('readable', () => {\n var data = input.read();\n if (data)\n hmac.update(data);\n else {\n console.log(`${hmac.digest('hex')} ${filename}`);\n }\n});\n
\n",
"signatures": [
{
"params": [
{
"name": "algorithm"
},
{
"name": "key"
}
]
}
]
},
{
"textRaw": "crypto.createSign(algorithm)",
"type": "method",
"name": "createSign",
"desc": "Creates and returns a Sign
object that uses the given algorithm
. On\nrecent OpenSSL releases, openssl list-public-key-algorithms
will\ndisplay the available signing algorithms. One example is 'RSA-SHA256'
.
Creates and returns a Verify
object that uses the given algorithm. On\nrecent OpenSSL releases, openssl list-public-key-algorithms
will\ndisplay the available signing algorithms. One example is 'RSA-SHA256'
.
Returns an array with the names of the supported cipher algorithms.
\nExample:
\nconst ciphers = crypto.getCiphers();\nconsole.log(ciphers); // ['aes-128-cbc', 'aes-128-ccm', ...]\n
\n",
"signatures": [
{
"params": []
}
]
},
{
"textRaw": "crypto.getCurves()",
"type": "method",
"name": "getCurves",
"desc": "Returns an array with the names of the supported elliptic curves.
\nExample:
\nconst curves = crypto.getCurves();\nconsole.log(curves); // ['secp256k1', 'secp384r1', ...]\n
\n",
"signatures": [
{
"params": []
}
]
},
{
"textRaw": "crypto.getDiffieHellman(group_name)",
"type": "method",
"name": "getDiffieHellman",
"desc": "Creates a predefined DiffieHellman
key exchange object. The\nsupported groups are: 'modp1'
, 'modp2'
, 'modp5'
(defined in\n[RFC 2412][], but see [Caveats][]) and 'modp14'
, 'modp15'
,\n'modp16'
, 'modp17'
, 'modp18'
(defined in [RFC 3526][]). The\nreturned object mimics the interface of objects created by\n[crypto.createDiffieHellman()
][], but will not allow changing\nthe keys (with [diffieHellman.setPublicKey()
][] for example). The\nadvantage of using this method is that the parties do not have to\ngenerate nor exchange a group modulus beforehand, saving both processor\nand communication time.
Example (obtaining a shared secret):
\nconst crypto = require('crypto');\nconst alice = crypto.getDiffieHellman('modp14');\nconst bob = crypto.getDiffieHellman('modp14');\n\nalice.generateKeys();\nbob.generateKeys();\n\nconst alice_secret = alice.computeSecret(bob.getPublicKey(), null, 'hex');\nconst bob_secret = bob.computeSecret(alice.getPublicKey(), null, 'hex');\n\n/* alice_secret and bob_secret should be the same */\nconsole.log(alice_secret == bob_secret);\n
\n",
"signatures": [
{
"params": [
{
"name": "group_name"
}
]
}
]
},
{
"textRaw": "crypto.getHashes()",
"type": "method",
"name": "getHashes",
"desc": "Returns an array with the names of the supported hash algorithms.
\nExample:
\nconst hashes = crypto.getHashes();\nconsole.log(hashes); // ['sha', 'sha1', 'sha1WithRSAEncryption', ...]\n
\n",
"signatures": [
{
"params": []
}
]
},
{
"textRaw": "crypto.pbkdf2(password, salt, iterations, keylen, digest, callback)",
"type": "method",
"name": "pbkdf2",
"desc": "Provides an asynchronous Password-Based Key Derivation Function 2 (PBKDF2)\nimplementation. A selected HMAC digest algorithm specified by digest
is\napplied to derive a key of the requested byte length (keylen
) from the\npassword
, salt
and iterations
.
The supplied callback
function is called with two arguments: err
and\nderivedKey
. If an error occurs, err
will be set; otherwise err
will be\nnull. The successfully generated derivedKey
will be passed as a [Buffer
][].
The iterations
argument must be a number set as high as possible. The\nhigher the number of iterations, the more secure the derived key will be,\nbut will take a longer amount of time to complete.
The salt
should also be as unique as possible. It is recommended that the\nsalts are random and their lengths are greater than 16 bytes. See\n[NIST SP 800-132][] for details.
Example:
\nconst crypto = require('crypto');\ncrypto.pbkdf2('secret', 'salt', 100000, 512, 'sha512', (err, key) => {\n if (err) throw err;\n console.log(key.toString('hex')); // 'c5e478d...1469e50'\n});\n
\nAn array of supported digest functions can be retrieved using\n[crypto.getHashes()
][].
Provides a synchronous Password-Based Key Derivation Function 2 (PBKDF2)\nimplementation. A selected HMAC digest algorithm specified by digest
is\napplied to derive a key of the requested byte length (keylen
) from the\npassword
, salt
and iterations
.
If an error occurs an Error will be thrown, otherwise the derived key will be\nreturned as a [Buffer
][].
The iterations
argument must be a number set as high as possible. The\nhigher the number of iterations, the more secure the derived key will be,\nbut will take a longer amount of time to complete.
The salt
should also be as unique as possible. It is recommended that the\nsalts are random and their lengths are greater than 16 bytes. See\n[NIST SP 800-132][] for details.
Example:
\nconst crypto = require('crypto');\nconst key = crypto.pbkdf2Sync('secret', 'salt', 100000, 512, 'sha512');\nconsole.log(key.toString('hex')); // 'c5e478d...1469e50'\n
\nAn array of supported digest functions can be retrieved using\n[crypto.getHashes()
][].
Decrypts buffer
with private_key
.
private_key
can be an object or a string. If private_key
is a string, it is\ntreated as the key with no passphrase and will use RSA_PKCS1_OAEP_PADDING
.\nIf private_key
is an object, it is interpreted as a hash object with the\nkeys:
key
: {String} - PEM encoded private keypassphrase
: {String} - Optional passphrase for the private keypadding
: An optional padding value, one of the following:crypto.constants.RSA_NO_PADDING
crypto.constants.RSA_PKCS1_PADDING
crypto.constants.RSA_PKCS1_OAEP_PADDING
All paddings are defined in crypto.constants
.
Encrypts buffer
with private_key
.
private_key
can be an object or a string. If private_key
is a string, it is\ntreated as the key with no passphrase and will use RSA_PKCS1_PADDING
.\nIf private_key
is an object, it is interpreted as a hash object with the\nkeys:
key
: {String} - PEM encoded private keypassphrase
: {String} - Optional passphrase for the private keypadding
: An optional padding value, one of the following:crypto.constants.RSA_NO_PADDING
crypto.constants.RSA_PKCS1_PADDING
crypto.constants.RSA_PKCS1_OAEP_PADDING
All paddings are defined in crypto.constants
.
Decrypts buffer
with public_key
.
public_key
can be an object or a string. If public_key
is a string, it is\ntreated as the key with no passphrase and will use RSA_PKCS1_PADDING
.\nIf public_key
is an object, it is interpreted as a hash object with the\nkeys:
key
: {String} - PEM encoded public keypassphrase
: {String} - Optional passphrase for the private keypadding
: An optional padding value, one of the following:crypto.constants.RSA_NO_PADDING
crypto.constants.RSA_PKCS1_PADDING
crypto.constants.RSA_PKCS1_OAEP_PADDING
Because RSA public keys can be derived from private keys, a private key may\nbe passed instead of a public key.
\nAll paddings are defined in crypto.constants
.
Encrypts buffer
with public_key
.
public_key
can be an object or a string. If public_key
is a string, it is\ntreated as the key with no passphrase and will use RSA_PKCS1_OAEP_PADDING
.\nIf public_key
is an object, it is interpreted as a hash object with the\nkeys:
key
: {String} - PEM encoded public keypassphrase
: {String} - Optional passphrase for the private keypadding
: An optional padding value, one of the following:crypto.constants.RSA_NO_PADDING
crypto.constants.RSA_PKCS1_PADDING
crypto.constants.RSA_PKCS1_OAEP_PADDING
Because RSA public keys can be derived from private keys, a private key may\nbe passed instead of a public key.
\nAll paddings are defined in crypto.constants
.
Generates cryptographically strong pseudo-random data. The size
argument\nis a number indicating the number of bytes to generate.
If a callback
function is provided, the bytes are generated asynchronously\nand the callback
function is invoked with two arguments: err
and buf
.\nIf an error occurs, err
will be an Error object; otherwise it is null. The\nbuf
argument is a [Buffer
][] containing the generated bytes.
// Asynchronous\nconst crypto = require('crypto');\ncrypto.randomBytes(256, (err, buf) => {\n if (err) throw err;\n console.log(`${buf.length} bytes of random data: ${buf.toString('hex')}`);\n});\n
\nIf the callback
function is not provided, the random bytes are generated\nsynchronously and returned as a [Buffer
][]. An error will be thrown if\nthere is a problem generating the bytes.
// Synchronous\nconst buf = crypto.randomBytes(256);\nconsole.log(\n `${buf.length} bytes of random data: ${buf.toString('hex')}`);\n
\nThe crypto.randomBytes()
method will block until there is sufficient entropy.\nThis should normally never take longer than a few milliseconds. The only time\nwhen generating the random bytes may conceivably block for a longer period of\ntime is right after boot, when the whole system is still low on entropy.
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
\nis a bit field taking one of or a mix of the following flags (defined in\ncrypto.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