crypto: Cleanup

1. Remove extraneous 'buffer' arguments.
2. Abstract out the 'toBuf' method.
3. Nicely organize DiffieHellman/DiffieHellmanGroup methods.

/cc @indutny

Author: isaacs

lib/crypto.js

@@ -37,6 +37,16 @@ try {
   var crypto = false;
 }
 
+// This is here because many functions accepted binary strings without
+// any explicit encoding in older versions of node, and we don't want
+// to break them unnecessarily.
+function toBuf(str, encoding) {
+  encoding = encoding || 'binary';
+  if (typeof str === 'string' && encoding !== 'buffer')
+    str = new Buffer(str, encoding);
+  return str;
+}
+
 var assert = require('assert');
 var StringDecoder = require('string_decoder').StringDecoder;
 
@@ -117,11 +127,11 @@ exports.createCredentials = function(options, context) {
   if (options.pfx) {
     var pfx = options.pfx;
     var passphrase = options.passphrase;
-    // legacy
-    if (typeof pfx === 'string')
-      pfx = new Buffer(pfx, 'binary');
-    if (passphrase && typeof passphrase === 'string')
-      passphrase = new Buffer(passphrase, 'binary');
+
+    pfx = toBuf(pfx);
+    if (passphrase)
+      passphrase = toBuf(passphrase);
+
     if (passphrase) {
       c.context.loadPKCS12(pfx, passphrase);
     } else {
@@ -142,17 +152,16 @@ function Hash(algorithm) {
 
 Hash.prototype.update = function(data, encoding) {
   encoding = encoding || exports.DEFAULT_ENCODING;
-  if (encoding === 'buffer')
-    encoding = null;
-  if (typeof data === 'string')
-    data = new Buffer(data, encoding);
+  if (encoding === 'buffer' && typeof encoding === 'string')
+    encoding = 'binary';
+  data = toBuf(data, encoding);
   this._binding.update(data);
   return this;
 };
 
 Hash.prototype.digest = function(outputEncoding) {
   outputEncoding = outputEncoding || exports.DEFAULT_ENCODING;
-  var result = this._binding.digest('buffer');
+  var result = this._binding.digest();
   if (outputEncoding && outputEncoding !== 'buffer')
     result = result.toString(outputEncoding);
   return result;
@@ -165,10 +174,7 @@ function Hmac(hmac, key) {
   if (!(this instanceof Hmac))
     return new Hmac(hmac, key);
   this._binding = new binding.Hmac();
-  // legacy
-  if (typeof key === 'string')
-    key = new Buffer(key, 'binary');
-  this._binding.init(hmac, key);
+  this._binding.init(hmac, toBuf(key));
 }
 
 Hmac.prototype.update = Hash.prototype.update;
@@ -188,21 +194,16 @@ function Cipher(cipher, password) {
     return new Cipher(cipher, password);
   this._binding = new binding.Cipher;
 
-  // legacy.
-  if (typeof password === 'string')
-    password = new Buffer(password, 'binary');
-
-  this._binding.init(cipher, password);
+  this._binding.init(cipher, toBuf(password));
   this._decoder = null;
 }
 
 Cipher.prototype.update = function(data, inputEncoding, outputEncoding) {
   inputEncoding = inputEncoding || exports.DEFAULT_ENCODING;
   outputEncoding = outputEncoding || exports.DEFAULT_ENCODING;
-  if (inputEncoding && inputEncoding !== 'buffer')
-    data = new Buffer(data, inputEncoding);
+  data = toBuf(data, inputEncoding);
 
-  var ret = this._binding.update(data, 'buffer', 'buffer');
+  var ret = this._binding.update(data);
 
   if (outputEncoding && outputEncoding !== 'buffer') {
     this._decoder = getDecoder(this._decoder, outputEncoding);
@@ -214,7 +215,7 @@ Cipher.prototype.update = function(data, inputEncoding, outputEncoding) {
 
 Cipher.prototype.final = function(outputEncoding) {
   outputEncoding = outputEncoding || exports.DEFAULT_ENCODING;
-  var ret = this._binding.final('buffer');
+  var ret = this._binding.final();
 
   if (outputEncoding && outputEncoding !== 'buffer') {
     this._decoder = getDecoder(this._decoder, outputEncoding);
@@ -235,13 +236,8 @@ exports.createCipheriv = exports.Cipheriv = Cipheriv;
 function Cipheriv(cipher, key, iv) {
   if (!(this instanceof Cipheriv))
     return new Cipheriv(cipher, key, iv);
-  // legacy
-  if (typeof key === 'string')
-    key = new Buffer(key, 'binary');
-  if (typeof iv === 'string')
-    iv = new Buffer(iv, 'binary');
   this._binding = new binding.Cipher();
-  this._binding.initiv(cipher, key, iv);
+  this._binding.initiv(cipher, toBuf(key), toBuf(iv));
   this._decoder = null;
 }
 
@@ -255,12 +251,8 @@ function Decipher(cipher, password) {
   if (!(this instanceof Decipher))
     return new Decipher(cipher, password);
 
-  // legacy.
-  if (typeof password === 'string')
-    password = new Buffer(password, 'binary');
-
   this._binding = new binding.Decipher;
-  this._binding.init(cipher, password);
+  this._binding.init(cipher, toBuf(password));
   this._decoder = null;
 }
 
@@ -274,13 +266,9 @@ exports.createDecipheriv = exports.Decipheriv = Decipheriv;
 function Decipheriv(cipher, key, iv) {
   if (!(this instanceof Decipheriv))
     return new Decipheriv(cipher, key, iv);
-  // legacy
-  if (typeof key === 'string')
-    key = new Buffer(key, 'binary');
-  if (typeof iv === 'string')
-    iv = new Buffer(iv, 'binary');
+
   this._binding = new binding.Decipher;
-  this._binding.initiv(cipher, key, iv);
+  this._binding.initiv(cipher, toBuf(key), toBuf(iv));
   this._decoder = null;
 }
 
@@ -301,14 +289,12 @@ function Sign(algorithm) {
 Sign.prototype.update = Hash.prototype.update;
 
 Sign.prototype.sign = function(key, encoding) {
-  // legacy.
-  if (typeof key === 'string')
-    key = new Buffer(key, 'binary');
-
   encoding = encoding || exports.DEFAULT_ENCODING;
-  var ret = this._binding.sign(key, 'buffer');
+  var ret = this._binding.sign(toBuf(key));
+
   if (encoding && encoding !== 'buffer')
     ret = ret.toString(encoding);
+
   return ret;
 };
 
@@ -325,17 +311,8 @@ function Verify(algorithm) {
 Verify.prototype.update = Hash.prototype.update;
 
 Verify.prototype.verify = function(object, signature, sigEncoding) {
-  // legacy.
-  if (typeof object === 'string')
-    object = new Buffer(object, 'binary');
-
   sigEncoding = sigEncoding || exports.DEFAULT_ENCODING;
-  if (sigEncoding === 'buffer')
-    sigEncoding = null;
-  if (sigEncoding || typeof signature === 'string')
-    signature = new Buffer(signature, sigEncoding);
-
-  return this._binding.verify(object, signature, 'buffer');
+  return this._binding.verify(toBuf(object), toBuf(signature, sigEncoding));
 };
 
 exports.createDiffieHellman = exports.DiffieHellman = DiffieHellman;
@@ -348,63 +325,101 @@ function DiffieHellman(sizeOrKey, encoding) {
     this._binding = new binding.DiffieHellman();
   else {
     encoding = encoding || exports.DEFAULT_ENCODING;
-    if (encoding === 'buffer')
-      encoding = null;
-    if (typeof sizeOrKey === 'string')
-      sizeOrKey = new Buffer(sizeOrKey, encoding);
-    this._binding = new binding.DiffieHellman(sizeOrKey, 'buffer');
+    sizeOrKey = toBuf(sizeOrKey, encoding);
+    this._binding = new binding.DiffieHellman(sizeOrKey);
   }
 }
 
-DiffieHellman.prototype.generateKeys = function(encoding) {
-  var keys = this._binding.generateKeys('buffer');
+
+exports.DiffieHellmanGroup =
+    exports.createDiffieHellmanGroup =
+    exports.getDiffieHellman = DiffieHellmanGroup;
+
+function DiffieHellmanGroup(name) {
+  if (!(this instanceof DiffieHellmanGroup))
+    return new DiffieHellmanGroup(name);
+  this._binding = new binding.DiffieHellmanGroup(name);
+}
+
+
+
+DiffieHellmanGroup.prototype.generateKeys =
+    DiffieHellman.prototype.generateKeys =
+    dhGenerateKeys;
+
+function dhGenerateKeys(encoding) {
+  var keys = this._binding.generateKeys();
   encoding = encoding || exports.DEFAULT_ENCODING;
   if (encoding && encoding !== 'buffer')
     keys = keys.toString(encoding);
   return keys;
 };
 
-DiffieHellman.prototype.computeSecret = function(key, inEnc, outEnc) {
+
+
+DiffieHellmanGroup.prototype.computeSecret =
+    DiffieHellman.prototype.computeSecret = 
+    dhComputeSecret;
+
+function dhComputeSecret(key, inEnc, outEnc) {
   inEnc = inEnc || exports.DEFAULT_ENCODING;
   outEnc = outEnc || exports.DEFAULT_ENCODING;
-  if (inEnc === 'buffer')
-    inEnc = null;
-  if (outEnc === 'buffer')
-    outEnc = null;
-  if (inEnc || typeof key === 'string')
-    key = new Buffer(key, inEnc);
-  var ret = this._binding.computeSecret(key, 'buffer', 'buffer');
-  if (outEnc)
+  var ret = this._binding.computeSecret(toBuf(key, inEnc));
+  if (outEnc && outEnc !== 'buffer')
     ret = ret.toString(outEnc);
   return ret;
 };
 
-DiffieHellman.prototype.getPrime = function(encoding) {
-  var prime = this._binding.getPrime('buffer');
+
+
+DiffieHellmanGroup.prototype.getPrime =
+    DiffieHellman.prototype.getPrime =
+    dhGetPrime;
+
+function dhGetPrime(encoding) {
+  var prime = this._binding.getPrime();
   encoding = encoding || exports.DEFAULT_ENCODING;
   if (encoding && encoding !== 'buffer')
     prime = prime.toString(encoding);
   return prime;
 };
 
-DiffieHellman.prototype.getGenerator = function(encoding) {
-  var generator = this._binding.getGenerator('buffer');
+
+
+DiffieHellmanGroup.prototype.getGenerator =
+    DiffieHellman.prototype.getGenerator =
+    dhGetGenerator;
+
+function dhGetGenerator(encoding) {
+  var generator = this._binding.getGenerator();
   encoding = encoding || exports.DEFAULT_ENCODING;
   if (encoding && encoding !== 'buffer')
     generator = generator.toString(encoding);
   return generator;
 };
 
-DiffieHellman.prototype.getPublicKey = function(encoding) {
-  var key = this._binding.getPublicKey('buffer');
+
+
+DiffieHellmanGroup.prototype.getPublicKey =
+    DiffieHellman.prototype.getPublicKey =
+    dhGetPublicKey;
+
+function dhGetPublicKey(encoding) {
+  var key = this._binding.getPublicKey();
   encoding = encoding || exports.DEFAULT_ENCODING;
   if (encoding && encoding !== 'buffer')
     key = key.toString(encoding);
   return key;
 };
 
-DiffieHellman.prototype.getPrivateKey = function(encoding) {
-  var key = this._binding.getPrivateKey('buffer');
+
+
+DiffieHellmanGroup.prototype.getPrivateKey =
+    DiffieHellman.prototype.getPrivateKey =
+    dhGetPrivateKey;
+
+function dhGetPrivateKey (encoding) {
+  var key = this._binding.getPrivateKey();
   encoding = encoding || exports.DEFAULT_ENCODING;
   if (encoding && encoding !== 'buffer')
     key = key.toString(encoding);
@@ -413,59 +428,21 @@ DiffieHellman.prototype.getPrivateKey = function(encoding) {
 
 DiffieHellman.prototype.setPublicKey = function(key, encoding) {
   encoding = encoding || exports.DEFAULT_ENCODING;
-  if (encoding === 'buffer')
-    encoding = null;
-  if (encoding || typeof key === 'string')
-    key = new Buffer(key, encoding);
-  this._binding.setPublicKey(key, 'buffer');
+  this._binding.setPublicKey(toBuf(key, encoding));
   return this;
 };
 
 DiffieHellman.prototype.setPrivateKey = function(key, encoding) {
   encoding = encoding || exports.DEFAULT_ENCODING;
-  if (encoding === 'buffer')
-    encoding = null;
-  if (encoding || typeof key === 'string')
-    key = new Buffer(key, encoding);
-  this._binding.setPrivateKey(key, 'buffer');
+  this._binding.setPrivateKey(toBuf(key, encoding));
   return this;
 };
 
 
 
-exports.DiffieHellmanGroup =
-    exports.createDiffieHellmanGroup =
-    exports.getDiffieHellman = DiffieHellmanGroup;
-
-function DiffieHellmanGroup(name) {
-  if (!(this instanceof DiffieHellmanGroup))
-    return new DiffieHellmanGroup(name);
-  this._binding = new binding.DiffieHellmanGroup(name);
-}
-
-DiffieHellmanGroup.prototype.generateKeys =
-    DiffieHellman.prototype.generateKeys;
-
-DiffieHellmanGroup.prototype.computeSecret =
-    DiffieHellman.prototype.computeSecret;
-
-DiffieHellmanGroup.prototype.getPrime =
-    DiffieHellman.prototype.getPrime;
-
-DiffieHellmanGroup.prototype.getGenerator =
-    DiffieHellman.prototype.getGenerator;
-
-DiffieHellmanGroup.prototype.getPublicKey =
-    DiffieHellman.prototype.getPublicKey;
-
-DiffieHellmanGroup.prototype.getPrivateKey =
-    DiffieHellman.prototype.getPrivateKey;
-
 exports.pbkdf2 = function(password, salt, iterations, keylen, callback) {
-  if (typeof password === 'string')
-    password = new Buffer(password, 'binary');
-  if (typeof salt === 'string')
-    salt = new Buffer(salt, 'binary');
+  password = toBuf(password);
+  salt = toBuf(salt);
 
   if (exports.DEFAULT_ENCODING === 'buffer')
     return binding.PBKDF2(password, salt, iterations, keylen, callback);