crypto: add crypto.sign() and crypto.verify()

doc/api/crypto.md

@@ -2659,6 +2659,35 @@ added: v10.0.0
 Enables the FIPS compliant crypto provider in a FIPS-enabled Node.js build.
 Throws an error if FIPS mode is not available.
 
+### crypto.sign(algorithm, data, key)
+<!-- YAML
+added: REPLACEME
+-->
+* `algorithm` {string | null | undefined}
+* `data` {Buffer | TypedArray | DataView}
+* `key` {Object | string | Buffer | KeyObject}
+* Returns: {Buffer}
+
+Calculates and returns the signature for `data` using the given private key and
+algorithm. If `algorithm` is `null` or `undefined`, then the algorithm is
+dependent upon the key type (especially Ed25519 and Ed448).
+
+If `key` is not a [`KeyObject`][], this function behaves as if `key` had been
+passed to [`crypto.createPrivateKey()`][]. If it is an object, the following
+additional properties can be passed:
+
+* `padding`: {integer} - Optional padding value for RSA, one of the following:
+  * `crypto.constants.RSA_PKCS1_PADDING` (default)
+  * `crypto.constants.RSA_PKCS1_PSS_PADDING`
+
+  Note that `RSA_PKCS1_PSS_PADDING` will use MGF1 with the same hash function
+  used to sign the message as specified in section 3.1 of [RFC 4055][].
+* `saltLength`: {integer} - salt length for when padding is
+  `RSA_PKCS1_PSS_PADDING`. The special value
+  `crypto.constants.RSA_PSS_SALTLEN_DIGEST` sets the salt length to the digest
+  size, `crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN` (default) sets it to the
+  maximum permissible value.
+
 ### crypto.timingSafeEqual(a, b)
 <!-- YAML
 added: v6.6.0
@@ -2680,6 +2709,41 @@ Use of `crypto.timingSafeEqual` does not guarantee that the *surrounding* code
 is timing-safe. Care should be taken to ensure that the surrounding code does
 not introduce timing vulnerabilities.
 
+### crypto.verify(algorithm, data, key, signature)
+<!-- YAML
+added: REPLACEME
+-->
+* `algorithm` {string | null | undefined}
+* `data` {Buffer | TypedArray | DataView}
+* `key` {Object | string | Buffer | KeyObject}
+* `signature` {Buffer | TypedArray | DataView}
+* Returns: {boolean}
+
+Verifies the given signature for `data` using the given key and algorithm. If
+`algorithm` is `null` or `undefined`, then the algorithm is dependent upon the
+key type (especially Ed25519 and Ed448).
+
+If `key` is not a [`KeyObject`][], this function behaves as if `key` had been
+passed to [`crypto.createPublicKey()`][]. If it is an object, the following
+additional properties can be passed:
+
+* `padding`: {integer} - Optional padding value for RSA, one of the following:
+  * `crypto.constants.RSA_PKCS1_PADDING` (default)
+  * `crypto.constants.RSA_PKCS1_PSS_PADDING`
+
+  Note that `RSA_PKCS1_PSS_PADDING` will use MGF1 with the same hash function
+  used to sign the message as specified in section 3.1 of [RFC 4055][].
+* `saltLength`: {integer} - salt length for when padding is
+  `RSA_PKCS1_PSS_PADDING`. The special value
+  `crypto.constants.RSA_PSS_SALTLEN_DIGEST` sets the salt length to the digest
+  size, `crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN` (default) sets it to the
+  maximum permissible value.
+
+The `signature` argument is the previously calculated signature for the `data`.
+
+Because public keys can be derived from private keys, a private key or a public
+key may be passed for `key`.
+
 ## Notes
 
 ### Legacy Streams API (pre Node.js v0.10)

lib/crypto.js

@@ -80,7 +80,9 @@ const {
 } = require('internal/crypto/cipher');
 const {
   Sign,
-  Verify
+  signOneShot,
+  Verify,
+  verifyOneShot
 } = require('internal/crypto/sig');
 const {
   Hash,
@@ -174,12 +176,14 @@ module.exports = exports = {
   randomFillSync,
   scrypt,
   scryptSync,
+  sign: signOneShot,
   setEngine,
   timingSafeEqual,
   getFips: !fipsMode ? getFipsDisabled :
     fipsForced ? getFipsForced : getFipsCrypto,
   setFips: !fipsMode ? setFipsDisabled :
     fipsForced ? setFipsForced : setFipsCrypto,
+  verify: verifyOneShot,
 
   // Classes
   Certificate,

lib/internal/crypto/sig.js

@@ -2,10 +2,16 @@
 
 const {
   ERR_CRYPTO_SIGN_KEY_REQUIRED,
+  ERR_INVALID_ARG_TYPE,
   ERR_INVALID_OPT_VALUE
 } = require('internal/errors').codes;
 const { validateString } = require('internal/validators');
-const { Sign: _Sign, Verify: _Verify } = internalBinding('crypto');
+const {
+  Sign: _Sign,
+  Verify: _Verify,
+  signOneShot: _signOneShot,
+  verifyOneShot: _verifyOneShot
+} = internalBinding('crypto');
 const {
   RSA_PSS_SALTLEN_AUTO,
   RSA_PKCS1_PADDING
@@ -22,6 +28,7 @@ const {
   preparePublicOrPrivateKey
 } = require('internal/crypto/keys');
 const { Writable } = require('stream');
+const { isArrayBufferView } = require('internal/util/types');
 
 function Sign(algorithm, options) {
   if (!(this instanceof Sign))
@@ -91,6 +98,35 @@ Sign.prototype.sign = function sign(options, encoding) {
   return ret;
 };
 
+function signOneShot(algorithm, data, key) {
+  if (algorithm != null)
+    validateString(algorithm, 'algorithm');
+
+  if (!isArrayBufferView(data)) {
+    throw new ERR_INVALID_ARG_TYPE(
+      'data',
+      ['Buffer', 'TypedArray', 'DataView'],
+      data
+    );
+  }
+
+  if (!key)
+    throw new ERR_CRYPTO_SIGN_KEY_REQUIRED();
+
+  const {
+    data: keyData,
+    format: keyFormat,
+    type: keyType,
+    passphrase: keyPassphrase
+  } = preparePrivateKey(key);
+
+  // Options specific to RSA
+  const rsaPadding = getPadding(key);
+  const pssSaltLength = getSaltLength(key);
+
+  return _signOneShot(keyData, keyFormat, keyType, keyPassphrase, data,
+                      algorithm, rsaPadding, pssSaltLength);
+}
 
 function Verify(algorithm, options) {
   if (!(this instanceof Verify))
@@ -132,7 +168,44 @@ Verify.prototype.verify = function verify(options, signature, sigEncoding) {
 
 legacyNativeHandle(Verify);
 
+function verifyOneShot(algorithm, data, key, signature) {
+  if (algorithm != null)
+    validateString(algorithm, 'algorithm');
+
+  if (!isArrayBufferView(data)) {
+    throw new ERR_INVALID_ARG_TYPE(
+      'data',
+      ['Buffer', 'TypedArray', 'DataView'],
+      data
+    );
+  }
+
+  const {
+    data: keyData,
+    format: keyFormat,
+    type: keyType,
+    passphrase: keyPassphrase
+  } = preparePublicOrPrivateKey(key);
+
+  // Options specific to RSA
+  const rsaPadding = getPadding(key);
+  const pssSaltLength = getSaltLength(key);
+
+  if (!isArrayBufferView(signature)) {
+    throw new ERR_INVALID_ARG_TYPE(
+      'signature',
+      ['Buffer', 'TypedArray', 'DataView'],
+      signature
+    );
+  }
+
+  return _verifyOneShot(keyData, keyFormat, keyType, keyPassphrase, signature,
+                        data, algorithm, rsaPadding, pssSaltLength);
+}
+
 module.exports = {
   Sign,
-  Verify
+  signOneShot,
+  Verify,
+  verifyOneShot
 };