Add new generation algorithm

The scrypt-genpass compatible one is now the legacy algorithm
(activated with -L or --legacy).

NewPasswordGenerator.m

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2016, Jonathan Schleifer <js@heap.zone>
+ *
+ * https://heap.zone/git/?p=scrypt-pwgen.git
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice is present in all copies.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#import "NewPasswordGenerator.h"
+
+@implementation NewPasswordGenerator
+@synthesize length = _length, site = _site, passphrase = _passphrase;
+@synthesize output = _output;
+
++ (instancetype)generator
+{
+	return [[[self alloc] init] autorelease];
+}
+
+- init
+{
+	self = [super init];
+
+	_length = 16;
+
+	return self;
+}
+
+- (void)derivePassword
+{
+	OFSHA384Hash *siteHash = [OFSHA384Hash cryptoHash];
+	[siteHash updateWithBuffer: [_site UTF8String]
+			    length: [_site UTF8StringLength]];
+
+	if (_output != NULL) {
+		of_explicit_memset(_output, 0, _length);
+		[self freeMemory: _output];
+	}
+
+	_output = [self allocMemoryWithSize: _length + 1];
+
+	of_scrypt(8, 524288, 2, [siteHash digest],
+	    [[siteHash class] digestSize], _passphrase, strlen(_passphrase),
+	    _output, _length);
+
+	for (size_t i = 0; i < _length; i++)
+		_output[i] =
+		    "0123456789"
+		    "abcdefghijklmnopqrstuvwxyz"
+		    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+		    ".!"[_output[i] & 0x3F];
+}
+@end