doc: show keylen in pbkdf2 as a byte length

[platform/upstream/nodejs.git] / doc / api / crypto.markdown

diff --git a/doc/api/crypto.markdown b/doc/api/crypto.markdown
index de574bc..04d7af6 100644 (file)
--- a/doc/api/crypto.markdown
+++ b/doc/api/crypto.markdown
@@ -1,7 +1,6 @@
 # Crypto
 
 # Crypto
 

-    Stability: 2 - Unstable; API changes are being discussed for
-    future versions.  Breaking changes will be minimized.  See below.
+    Stability: 2 - Stable

 
 Use `require('crypto')` to access this module.
 
 
 Use `require('crypto')` to access this module.
 


@@ -12,6 +11,30 @@ It also offers a set of wrappers for OpenSSL's hash, hmac, cipher,
 decipher, sign and verify methods.
 
 
 decipher, sign and verify methods.
 
 

+## crypto.setEngine(engine[, flags])
+
+Load and set engine for some/all OpenSSL functions (selected by flags).
+
+`engine` could be either an id or a path to the engine's shared library.
+
+`flags` is optional and has `ENGINE_METHOD_ALL` value by default. It could take
+one of or mix of following flags (defined in `constants` module):
+
+* `ENGINE_METHOD_RSA`
+* `ENGINE_METHOD_DSA`
+* `ENGINE_METHOD_DH`
+* `ENGINE_METHOD_RAND`
+* `ENGINE_METHOD_ECDH`
+* `ENGINE_METHOD_ECDSA`
+* `ENGINE_METHOD_CIPHERS`
+* `ENGINE_METHOD_DIGESTS`
+* `ENGINE_METHOD_STORE`
+* `ENGINE_METHOD_PKEY_METH`
+* `ENGINE_METHOD_PKEY_ASN1_METH`
+* `ENGINE_METHOD_ALL`
+* `ENGINE_METHOD_NONE`
+
+

 ## crypto.getCiphers()
 
 Returns an array with the names of the supported ciphers.
 ## crypto.getCiphers()
 
 Returns an array with the names of the supported ciphers.


@@ -19,7 +42,7 @@ Returns an array with the names of the supported ciphers.
 Example:
 
     var ciphers = crypto.getCiphers();
 Example:
 
     var ciphers = crypto.getCiphers();

-    console.log(ciphers); // ['AES128-SHA', 'AES256-SHA', ...]
+    console.log(ciphers); // ['aes-128-cbc', 'aes-128-ccm', ...]

 
 
 ## crypto.getHashes()
 
 
 ## crypto.getHashes()


@@ -32,8 +55,20 @@ Example:
     console.log(hashes); // ['sha', 'sha1', 'sha1WithRSAEncryption', ...]
 
 
     console.log(hashes); // ['sha', 'sha1', 'sha1WithRSAEncryption', ...]
 
 

+## crypto.getCurves()
+
+Returns an array with the names of the supported elliptic curves.
+
+Example:
+
+    var curves = crypto.getCurves();
+    console.log(curves); // ['secp256k1', 'secp384r1', ...]
+
+

 ## crypto.createCredentials(details)
 
 ## crypto.createCredentials(details)
 

+    Stability: 0 - Deprecated: Use [tls.createSecureContext][] instead.
+

 Creates a credentials object, with the optional details being a
 dictionary with keys:
 
 Creates a credentials object, with the optional details being a
 dictionary with keys:
 


@@ -51,7 +86,7 @@ dictionary with keys:
   <http://www.openssl.org/docs/apps/ciphers.html#CIPHER_LIST_FORMAT>
   for details on the format.
 
   <http://www.openssl.org/docs/apps/ciphers.html#CIPHER_LIST_FORMAT>
   for details on the format.
 

-If no 'ca' details are given, then node.js will use the default
+If no 'ca' details are given, then Node.js will use the default

 publicly trusted list of CAs as given in
 <http://mxr.mozilla.org/mozilla/source/security/nss/lib/ckfw/builtins/certdata.txt>.
 
 publicly trusted list of CAs as given in
 <http://mxr.mozilla.org/mozilla/source/security/nss/lib/ckfw/builtins/certdata.txt>.
 


@@ -96,11 +131,13 @@ digest.  The legacy `update` and `digest` methods are also supported.
 
 Returned by `crypto.createHash`.
 
 
 Returned by `crypto.createHash`.
 

-### hash.update(data, [input_encoding])
+### hash.update(data[, input_encoding])

 
 Updates the hash content with the given `data`, the encoding of which
 is given in `input_encoding` and can be `'utf8'`, `'ascii'` or
 
 Updates the hash content with the given `data`, the encoding of which
 is given in `input_encoding` and can be `'utf8'`, `'ascii'` or

-`'binary'`.  If no encoding is provided, then a buffer is expected.
+`'binary'`.  If no encoding is provided, and the input is a string, an
+encoding of `'binary'` is enforced. If `data` is a `Buffer` then
+`input_encoding` is ignored.

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


@@ -110,7 +147,7 @@ Calculates the digest of all of the passed data to be hashed.  The
 `encoding` can be `'hex'`, `'binary'` or `'base64'`.  If no encoding
 is provided, then a buffer is returned.
 
 `encoding` can be `'hex'`, `'binary'` or `'base64'`.  If no encoding
 is provided, then a buffer is returned.
 

-Note: `hash` object can not be used after `digest()` method been
+Note: `hash` object can not be used after `digest()` method has been

 called.
 
 
 called.
 
 


@@ -144,7 +181,7 @@ Calculates the digest of all of the passed data to the hmac.  The
 `encoding` can be `'hex'`, `'binary'` or `'base64'`.  If no encoding
 is provided, then a buffer is returned.
 
 `encoding` can be `'hex'`, `'binary'` or `'base64'`.  If no encoding
 is provided, then a buffer is returned.
 

-Note: `hmac` object can not be used after `digest()` method been
+Note: `hmac` object can not be used after `digest()` method has been

 called.
 
 
 called.
 
 


@@ -160,8 +197,18 @@ which must be a `'binary'` encoded string or a [buffer](buffer.html).
 
 It is a [stream](stream.html) that is both readable and writable.  The
 written data is used to compute the hash.  Once the writable side of
 
 It is a [stream](stream.html) that is both readable and writable.  The
 written data is used to compute the hash.  Once the writable side of

-the stream is ended, use the `read()` method to get the computed hash
-digest.  The legacy `update` and `digest` methods are also supported.
+the stream is ended, use the `read()` method to get the enciphered
+contents.  The legacy `update` and `final` methods are also supported.
+
+Note: `createCipher` derives keys with 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 you derive a key and iv yourself with [crypto.pbkdf2][] and to
+then use [createCipheriv()][] to create the cipher stream.

 
 ## crypto.createCipheriv(algorithm, key, iv)
 
 
 ## crypto.createCipheriv(algorithm, key, iv)
 


@@ -183,18 +230,19 @@ Returned by `crypto.createCipher` and `crypto.createCipheriv`.
 
 Cipher objects are [streams](stream.html) that are both readable and
 writable.  The written plain text data is used to produce the
 
 Cipher objects are [streams](stream.html) that are both readable and
 writable.  The written plain text data is used to produce the

-encrypted data on the the readable side.  The legacy `update` and
-`final` methods are also supported.
+encrypted data on the readable side.  The legacy `update` and `final`
+methods are also supported.

 
 

-### cipher.update(data, [input_encoding], [output_encoding])
+### cipher.update(data[, input_encoding][, output_encoding])

 
 Updates the cipher with `data`, the encoding of which is given in
 `input_encoding` and can be `'utf8'`, `'ascii'` or `'binary'`.  If no
 encoding is provided, then a buffer is expected.
 
 Updates the cipher with `data`, the encoding of which is given in
 `input_encoding` and can be `'utf8'`, `'ascii'` or `'binary'`.  If no
 encoding is provided, then a buffer is expected.

+If `data` is a `Buffer` then `input_encoding` is ignored.

 
 The `output_encoding` specifies the output format of the enciphered
 data, and can be `'binary'`, `'base64'` or `'hex'`.  If no encoding is
 
 The `output_encoding` specifies the output format of the enciphered
 data, and can be `'binary'`, `'base64'` or `'hex'`.  If no encoding is

-provided, then a buffer iis returned.
+provided, then a buffer is returned.

 
 Returns the enciphered contents, and can be called many times with new
 data as it is streamed.
 
 Returns the enciphered contents, and can be called many times with new
 data as it is streamed.


@@ -205,7 +253,7 @@ Returns any remaining enciphered contents, with `output_encoding`
 being one of: `'binary'`, `'base64'` or `'hex'`.  If no encoding is
 provided, then a buffer is returned.
 
 being one of: `'binary'`, `'base64'` or `'hex'`.  If no encoding is
 provided, then a buffer is returned.
 

-Note: `cipher` object can not be used after `final()` method been
+Note: `cipher` object can not be used after `final()` method has been

 called.
 
 ### cipher.setAutoPadding(auto_padding=true)
 called.
 
 ### cipher.setAutoPadding(auto_padding=true)


@@ -216,6 +264,19 @@ multiple of the cipher's block size or `final` will fail.  Useful for
 non-standard padding, e.g. using `0x0` instead of PKCS padding. You
 must call this before `cipher.final`.
 
 non-standard padding, e.g. using `0x0` instead of PKCS padding. You
 must call this before `cipher.final`.
 

+### cipher.getAuthTag()
+
+For authenticated encryption modes (currently supported: GCM), this
+method returns a `Buffer` that represents the _authentication tag_ that
+has been computed from the given data. Should be called after
+encryption has been completed using the `final` method!
+
+### cipher.setAAD(buffer)
+
+For authenticated encryption modes (currently supported: GCM), this
+method sets the value used for the additional authenticated data (AAD) input
+parameter.
+

 
 ## crypto.createDecipher(algorithm, password)
 
 
 ## crypto.createDecipher(algorithm, password)
 


@@ -238,11 +299,12 @@ writable.  The written enciphered data is used to produce the
 plain-text data on the the readable side.  The legacy `update` and
 `final` methods are also supported.
 
 plain-text data on the the readable side.  The legacy `update` and
 `final` methods are also supported.
 

-### decipher.update(data, [input_encoding], [output_encoding])
+### decipher.update(data[, input_encoding][, output_encoding])

 
 Updates the decipher with `data`, which is encoded in `'binary'`,
 `'base64'` or `'hex'`.  If no encoding is provided, then a buffer is
 expected.
 
 Updates the decipher with `data`, which is encoded in `'binary'`,
 `'base64'` or `'hex'`.  If no encoding is provided, then a buffer is
 expected.

+If `data` is a `Buffer` then `input_encoding` is ignored.

 
 The `output_decoding` specifies in what format to return the
 deciphered plaintext: `'binary'`, `'ascii'` or `'utf8'`.  If no
 
 The `output_decoding` specifies in what format to return the
 deciphered plaintext: `'binary'`, `'ascii'` or `'utf8'`.  If no


@@ -254,17 +316,32 @@ Returns any remaining plaintext which is deciphered, with
 `output_encoding` being one of: `'binary'`, `'ascii'` or `'utf8'`.  If
 no encoding is provided, then a buffer is returned.
 
 `output_encoding` being one of: `'binary'`, `'ascii'` or `'utf8'`.  If
 no encoding is provided, then a buffer is returned.
 

-Note: `decipher` object can not be used after `final()` method been
+Note: `decipher` object can not be used after `final()` method has been

 called.
 
 ### decipher.setAutoPadding(auto_padding=true)
 
 You can disable auto padding if the data has been encrypted without
 standard block padding to prevent `decipher.final` from checking and
 called.
 
 ### decipher.setAutoPadding(auto_padding=true)
 
 You can disable auto padding if the data has been encrypted without
 standard block padding to prevent `decipher.final` from checking and

-removing it. Can only work if the input data's length is a multiple of
+removing it. This will only work if the input data's length is a multiple of

 the ciphers block size. You must call this before streaming data to
 `decipher.update`.
 
 the ciphers block size. You must call this before streaming data to
 `decipher.update`.
 

+### decipher.setAuthTag(buffer)
+
+For authenticated encryption modes (currently supported: GCM), this
+method must be used to pass in the received _authentication tag_.
+If no tag is provided or if the ciphertext has been tampered with,
+`final` will throw, thus indicating that the ciphertext should
+be discarded due to failed authentication.
+
+### decipher.setAAD(buffer)
+
+For authenticated encryption modes (currently supported: GCM), this
+method sets the value used for the additional authenticated data (AAD) input
+parameter.
+
+

 ## crypto.createSign(algorithm)
 
 Creates and returns a signing object, with the given algorithm.  On
 ## crypto.createSign(algorithm)
 
 Creates and returns a signing object, with the given algorithm.  On


@@ -287,17 +364,24 @@ written, the `sign` method will return the signature.  The legacy
 Updates the sign object with data.  This can be called many times
 with new data as it is streamed.
 
 Updates the sign object with data.  This can be called many times
 with new data as it is streamed.
 

-### sign.sign(private_key, [output_format])
+### sign.sign(private_key[, output_format])

 
 Calculates the signature on all the updated data passed through the
 
 Calculates the signature on all the updated data passed through the

-sign.  `private_key` is a string containing the PEM encoded private
-key for signing.
+sign.
+
+`private_key` can be an object or a string. If `private_key` is a string, it is
+treated as the key with no passphrase.
+
+`private_key`:
+
+* `key` : A string holding the PEM encoded private key
+* `passphrase` : A string of passphrase for the private key

 
 Returns the signature in `output_format` which can be `'binary'`,
 `'hex'` or `'base64'`. If no encoding is provided, then a buffer is
 returned.
 
 
 Returns the signature in `output_format` which can be `'binary'`,
 `'hex'` or `'base64'`. If no encoding is provided, then a buffer is
 returned.
 

-Note: `sign` object can not be used after `sign()` method been
+Note: `sign` object can not be used after `sign()` method has been

 called.
 
 ## crypto.createVerify(algorithm)
 called.
 
 ## crypto.createVerify(algorithm)


@@ -322,7 +406,7 @@ supported.
 Updates the verifier object with data.  This can be called many times
 with new data as it is streamed.
 
 Updates the verifier object with data.  This can be called many times
 with new data as it is streamed.
 

-### verifier.verify(object, signature, [signature_format])
+### verifier.verify(object, signature[, signature_format])

 
 Verifies the signed data by using the `object` and `signature`.
 `object` is  a string containing a PEM encoded object, which can be
 
 Verifies the signed data by using the `object` and `signature`.
 `object` is  a string containing a PEM encoded object, which can be


@@ -334,19 +418,24 @@ If no encoding is specified, then a buffer is expected.
 Returns true or false depending on the validity of the signature for
 the data and public key.
 
 Returns true or false depending on the validity of the signature for
 the data and public key.
 

-Note: `verifier` object can not be used after `verify()` method been
+Note: `verifier` object can not be used after `verify()` method has been

 called.
 
 called.
 

-## crypto.createDiffieHellman(prime_length)
+## crypto.createDiffieHellman(prime_length[, generator])

 
 Creates a Diffie-Hellman key exchange object and generates a prime of
 
 Creates a Diffie-Hellman key exchange object and generates a prime of

-the given bit length. The generator used is `2`.
+`prime_length` bits and using an optional specific numeric `generator`.
+If no `generator` is specified, then `2` is used.

 
 

-## crypto.createDiffieHellman(prime, [encoding])
+## crypto.createDiffieHellman(prime[, prime_encoding][, generator][, generator_encoding])

 
 

-Creates a Diffie-Hellman key exchange object using the supplied prime.
-The generator used is `2`. Encoding can be `'binary'`, `'hex'`, or
-`'base64'`.  If no encoding is specified, then a buffer is expected.
+Creates a Diffie-Hellman key exchange object using the supplied `prime` and an
+optional specific `generator`.
+`generator` can be a number, string, or Buffer.
+If no `generator` is specified, then `2` is used.
+`prime_encoding` and `generator_encoding` can be `'binary'`, `'hex'`, or `'base64'`.
+If no `prime_encoding` is specified, then a Buffer is expected for `prime`.
+If no `generator_encoding` is specified, then a Buffer is expected for `generator`.

 
 ## Class: DiffieHellman
 
 
 ## Class: DiffieHellman
 


@@ -354,6 +443,17 @@ The class for creating Diffie-Hellman key exchanges.
 
 Returned by `crypto.createDiffieHellman`.
 
 
 Returned by `crypto.createDiffieHellman`.
 

+### diffieHellman.verifyError
+
+A bit field containing any warnings and/or errors as a result of a check performed
+during initialization. The following values are valid for this property
+(defined in `constants` module):
+
+* `DH_CHECK_P_NOT_SAFE_PRIME`
+* `DH_CHECK_P_NOT_PRIME`
+* `DH_UNABLE_TO_CHECK_GENERATOR`
+* `DH_NOT_SUITABLE_GENERATOR`
+

 ### diffieHellman.generateKeys([encoding])
 
 Generates private and public Diffie-Hellman key values, and returns
 ### diffieHellman.generateKeys([encoding])
 
 Generates private and public Diffie-Hellman key values, and returns


@@ -361,7 +461,7 @@ the public key in the specified encoding. This key should be
 transferred to the other party. Encoding can be `'binary'`, `'hex'`,
 or `'base64'`.  If no encoding is provided, then a buffer is returned.
 
 transferred to the other party. Encoding can be `'binary'`, `'hex'`,
 or `'base64'`.  If no encoding is provided, then a buffer is returned.
 

-### diffieHellman.computeSecret(other_public_key, [input_encoding], [output_encoding])
+### diffieHellman.computeSecret(other_public_key[, input_encoding][, output_encoding])

 
 Computes the shared secret using `other_public_key` as the other
 party's public key and returns the computed shared secret. Supplied
 
 Computes the shared secret using `other_public_key` as the other
 party's public key and returns the computed shared secret. Supplied


@@ -380,7 +480,7 @@ then a buffer is returned.
 
 ### diffieHellman.getGenerator([encoding])
 
 
 ### diffieHellman.getGenerator([encoding])
 

-Returns the Diffie-Hellman prime in the specified encoding, which can
+Returns the Diffie-Hellman generator in the specified encoding, which can

 be `'binary'`, `'hex'`, or `'base64'`. If no encoding is provided,
 then a buffer is returned.
 
 be `'binary'`, `'hex'`, or `'base64'`. If no encoding is provided,
 then a buffer is returned.
 


@@ -396,13 +496,13 @@ Returns the Diffie-Hellman private key in the specified encoding,
 which can be `'binary'`, `'hex'`, or `'base64'`. If no encoding is
 provided, then a buffer is returned.
 
 which can be `'binary'`, `'hex'`, or `'base64'`. If no encoding is
 provided, then a buffer is returned.
 

-### diffieHellman.setPublicKey(public_key, [encoding])
+### diffieHellman.setPublicKey(public_key[, encoding])

 
 Sets the Diffie-Hellman public key. Key encoding can be `'binary'`,
 `'hex'` or `'base64'`. If no encoding is provided, then a buffer is
 expected.
 
 
 Sets the Diffie-Hellman public key. Key encoding can be `'binary'`,
 `'hex'` or `'base64'`. If no encoding is provided, then a buffer is
 expected.
 

-### diffieHellman.setPrivateKey(private_key, [encoding])
+### diffieHellman.setPrivateKey(private_key[, encoding])

 
 Sets the Diffie-Hellman private key. Key encoding can be `'binary'`,
 `'hex'` or `'base64'`. If no encoding is provided, then a buffer is
 
 Sets the Diffie-Hellman private key. Key encoding can be `'binary'`,
 `'hex'` or `'base64'`. If no encoding is provided, then a buffer is


@@ -436,17 +536,111 @@ Example (obtaining a shared secret):
     /* alice_secret and bob_secret should be the same */
     console.log(alice_secret == bob_secret);
 
     /* alice_secret and bob_secret should be the same */
     console.log(alice_secret == bob_secret);
 

-## crypto.pbkdf2(password, salt, iterations, keylen, callback)
+## crypto.createECDH(curve_name)
+
+Creates an Elliptic Curve (EC) Diffie-Hellman key exchange object using a
+predefined curve specified by the `curve_name` string. Use [getCurves()][] to
+obtain a list of available curve names. On recent releases,
+`openssl ecparam -list_curves` will also display the name and description of
+each available elliptic curve.
+
+## Class: ECDH
+
+The class for creating EC Diffie-Hellman key exchanges.
+
+Returned by `crypto.createECDH`.
+
+### ECDH.generateKeys([encoding[, format]])
+
+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.
+
+Format specifies point encoding and can be `'compressed'`, `'uncompressed'`, or
+`'hybrid'`. If no format is provided - the point will be returned in
+`'uncompressed'` format.
+
+Encoding can be `'binary'`, `'hex'`, or `'base64'`. If no encoding is provided,
+then a buffer is returned.
+
+### ECDH.computeSecret(other_public_key[, input_encoding][, output_encoding])
+
+Computes the shared secret using `other_public_key` as the other
+party's public key and returns the computed shared secret. Supplied
+key is interpreted using specified `input_encoding`, and secret is
+encoded using specified `output_encoding`. Encodings can be
+`'binary'`, `'hex'`, or `'base64'`. If the input encoding is not
+provided, then a buffer is expected.
+
+If no output encoding is given, then a buffer is returned.
+
+### ECDH.getPublicKey([encoding[, format]])
+
+Returns the EC Diffie-Hellman public key in the specified encoding and format.
+
+Format specifies point encoding and can be `'compressed'`, `'uncompressed'`, or
+`'hybrid'`. If no format is provided - the point will be returned in
+`'uncompressed'` format.
+
+Encoding can be `'binary'`, `'hex'`, or `'base64'`. If no encoding is provided,
+then a buffer is returned.
+
+### ECDH.getPrivateKey([encoding])
+
+Returns the EC Diffie-Hellman private key in the specified encoding,
+which can be `'binary'`, `'hex'`, or `'base64'`. If no encoding is
+provided, then a buffer is returned.
+
+### ECDH.setPublicKey(public_key[, encoding])
+
+Sets the EC Diffie-Hellman public key. Key encoding can be `'binary'`,
+`'hex'` or `'base64'`. If no encoding is provided, then a buffer is
+expected.
+
+### ECDH.setPrivateKey(private_key[, encoding])
+
+Sets the EC Diffie-Hellman private key. Key encoding can be `'binary'`,
+`'hex'` or `'base64'`. If no encoding is provided, then a buffer is
+expected.
+
+Example (obtaining a shared secret):
+
+    var crypto = require('crypto');
+    var alice = crypto.createECDH('secp256k1');
+    var bob = crypto.createECDH('secp256k1');
+
+    alice.generateKeys();
+    bob.generateKeys();
+
+    var alice_secret = alice.computeSecret(bob.getPublicKey(), null, 'hex');
+    var bob_secret = bob.computeSecret(alice.getPublicKey(), null, 'hex');
+
+    /* alice_secret and bob_secret should be the same */
+    console.log(alice_secret == bob_secret);
+
+## crypto.pbkdf2(password, salt, iterations, keylen[, digest], callback)
+
+Asynchronous PBKDF2 function.  Applies the selected HMAC digest function
+(default: SHA1) to derive a key of the requested byte length from the password,
+salt and number of iterations.  The callback gets two arguments:
+`(err, derivedKey)`.
+
+Example:
+
+    crypto.pbkdf2('secret', 'salt', 4096, 64, 'sha256', function(err, key) {
+      if (err)
+        throw err;
+      console.log(key.toString('hex'));  // 'c5e478d...1469e50'
+    });

 
 

-Asynchronous PBKDF2 applies pseudorandom function HMAC-SHA1 to derive
-a key of given length from the given password, salt and iterations.
-The callback gets two arguments `(err, derivedKey)`.
+You can get a list of supported digest functions with
+[crypto.getHashes()](#crypto_crypto_gethashes).

 
 

-## crypto.pbkdf2Sync(password, salt, iterations, keylen)
+## crypto.pbkdf2Sync(password, salt, iterations, keylen[, digest])

 
 Synchronous PBKDF2 function.  Returns derivedKey or throws error.
 
 
 Synchronous PBKDF2 function.  Returns derivedKey or throws error.
 

-## crypto.randomBytes(size, [callback])
+## crypto.randomBytes(size[, callback])

 
 Generates cryptographically strong pseudo-random data. Usage:
 
 
 Generates cryptographically strong pseudo-random data. Usage:
 


@@ -457,12 +651,81 @@ Generates cryptographically strong pseudo-random data. Usage:
     });
 
     // sync
     });
 
     // sync

-    try {
-      var buf = crypto.randomBytes(256);
-      console.log('Have %d bytes of random data: %s', buf.length, buf);
-    } catch (ex) {
-      // handle error
-    }
+    const buf = crypto.randomBytes(256);
+    console.log('Have %d bytes of random data: %s', buf.length, buf);
+
+NOTE: This will block if there is insufficient entropy, although it should
+normally never take longer than a few milliseconds. The only time when this
+may conceivably block is right after boot, when the whole system is still
+low on entropy.
+
+## Class: Certificate
+
+The class used for working with signed public key & challenges. The most
+common usage for this series of functions is when dealing with the `<keygen>`
+element. http://www.openssl.org/docs/apps/spkac.html
+
+Returned by `crypto.Certificate`.
+
+### Certificate.verifySpkac(spkac)
+
+Returns true of false based on the validity of the SPKAC.
+
+### Certificate.exportChallenge(spkac)
+
+Exports the encoded public key from the supplied SPKAC.
+
+### Certificate.exportPublicKey(spkac)
+
+Exports the encoded challenge associated with the SPKAC.
+
+## crypto.publicEncrypt(public_key, buffer)
+
+Encrypts `buffer` with `public_key`. Only RSA is currently supported.
+
+`public_key` can be an object or a string. If `public_key` is a string, it is
+treated as the key with no passphrase and will use `RSA_PKCS1_OAEP_PADDING`.
+Since RSA public keys may be derived from private keys you may pass a private
+key to this method.
+
+`public_key`:
+
+* `key` : A string holding the PEM encoded private key
+* `passphrase` : An optional string of passphrase for the private key
+* `padding` : An optional padding value, one of the following:
+  * `constants.RSA_NO_PADDING`
+  * `constants.RSA_PKCS1_PADDING`
+  * `constants.RSA_PKCS1_OAEP_PADDING`
+
+NOTE: All paddings are defined in `constants` module.
+
+## crypto.publicDecrypt(public_key, buffer)
+
+See above for details. Has the same API as `crypto.publicEncrypt`. Default
+padding is `RSA_PKCS1_PADDING`.
+
+## crypto.privateDecrypt(private_key, buffer)
+
+Decrypts `buffer` with `private_key`.
+
+`private_key` can be an object or a string. If `private_key` is a string, it is
+treated as the key with no passphrase and will use `RSA_PKCS1_OAEP_PADDING`.
+
+`private_key`:
+
+* `key` : A string holding the PEM encoded private key
+* `passphrase` : An optional string of passphrase for the private key
+* `padding` : An optional padding value, one of the following:
+  * `constants.RSA_NO_PADDING`
+  * `constants.RSA_PKCS1_PADDING`
+  * `constants.RSA_PKCS1_OAEP_PADDING`
+
+NOTE: All paddings are defined in `constants` module.
+
+## crypto.privateEncrypt(private_key, buffer)
+
+See above for details. Has the same API as `crypto.privateDecrypt`.
+Default padding is `RSA_PKCS1_PADDING`.

 
 ## crypto.DEFAULT_ENCODING
 
 
 ## crypto.DEFAULT_ENCODING
 


@@ -477,12 +740,12 @@ as a temporary measure.
 
 ## Recent API Changes
 
 
 ## Recent API Changes
 

-The Crypto module was added to Node before there was the concept of a
+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 streaming classes don't have the typical methods found on
 unified Stream API, and before there were Buffer objects for handling
 binary data.
 
 As such, the streaming classes don't have the typical methods found on

-other Node classes, and many methods accepted and returned
+other Node.js classes, and many methods accepted and returned

 Binary-encoded strings by default rather than Buffers.  This was
 changed to use Buffers by default instead.
 
 Binary-encoded strings by default rather than Buffers.  This was
 changed to use Buffers by default instead.
 


@@ -508,7 +771,11 @@ temporary measure.
 
 [createCipher()]: #crypto_crypto_createcipher_algorithm_password
 [createCipheriv()]: #crypto_crypto_createcipheriv_algorithm_key_iv
 
 [createCipher()]: #crypto_crypto_createcipher_algorithm_password
 [createCipheriv()]: #crypto_crypto_createcipheriv_algorithm_key_iv

-[crypto.createDiffieHellman()]: #crypto_crypto_creatediffiehellman_prime_encoding
+[getCurves()]: #crypto_crypto_getcurves
+[crypto.createDiffieHellman()]: #crypto_crypto_creatediffiehellman_prime_prime_encoding_generator_generator_encoding
+[tls.createSecureContext]: tls.html#tls_tls_createsecurecontext_details

 [diffieHellman.setPublicKey()]: #crypto_diffiehellman_setpublickey_public_key_encoding
 [RFC 2412]: http://www.rfc-editor.org/rfc/rfc2412.txt
 [RFC 3526]: http://www.rfc-editor.org/rfc/rfc3526.txt
 [diffieHellman.setPublicKey()]: #crypto_diffiehellman_setpublickey_public_key_encoding
 [RFC 2412]: http://www.rfc-editor.org/rfc/rfc2412.txt
 [RFC 3526]: http://www.rfc-editor.org/rfc/rfc3526.txt

+[crypto.pbkdf2]: #crypto_crypto_pbkdf2_password_salt_iterations_keylen_digest_callback
+[EVP_BytesToKey]: https://www.openssl.org/docs/crypto/EVP_BytesToKey.html