Add new generation algorithm

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

LegacyPasswordGenerator.h

@@ -20,21 +20,13 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#import <ObjFW/ObjFW.h>
+#import "PasswordGenerator.h"
 
-@interface LegacyPasswordGenerator: OFObject
+@interface LegacyPasswordGenerator: OFObject <PasswordGenerator>
 {
 	size_t _length;
 	OFString *_site;
 	const char *_passphrase;
 	unsigned char *_output;
 }
-
-@property size_t length;
-@property (copy) OFString *site;
-@property const char *passphrase;
-@property (readonly) unsigned char *output;
-
-+ (instancetype)generator;
-- (void)derivePassword;
 @end

LegacyPasswordGenerator.m

@@ -23,8 +23,7 @@
 #import "LegacyPasswordGenerator.h"
 
 @implementation LegacyPasswordGenerator
-@synthesize length = _length, site = _site, passphrase = _passphrase;
+@synthesize site = _site, passphrase = _passphrase, output = _output;
-@synthesize output = _output;
 
 + (instancetype)generator
 {
@@ -40,6 +39,19 @@
 	return self;
 }
 
+- (void)setLength: (size_t)length
+{
+	if (length < 3)
+		@throw [OFInvalidArgumentException exception];
+
+	_length = length;
+}
+
+- (size_t)length
+{
+	return _length;
+}
+
 - (void)derivePassword
 {
 	OFSHA256Hash *siteHash = [OFSHA256Hash cryptoHash];

NewPasswordGenerator.h

@@ -0,0 +1,32 @@
+/*
+ * 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 "PasswordGenerator.h"
+
+@interface NewPasswordGenerator: OFObject <PasswordGenerator>
+{
+	size_t _length;
+	OFString *_site;
+	const char *_passphrase;
+	unsigned char *_output;
+}
+@end

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

PasswordGenerator.h

@@ -0,0 +1,33 @@
+/*
+ * 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 <ObjFW/ObjFW.h>
+
+@protocol PasswordGenerator
+@property size_t length;
+@property (copy) OFString *site;
+@property const char *passphrase;
+@property (readonly) unsigned char *output;
+
++ (instancetype)generator;
+- (void)derivePassword;
+@end

ScryptPWGen.h

@@ -25,6 +25,6 @@
 @interface ScryptPWGen: OFObject <OFApplicationDelegate>
 {
 	size_t _length;
-	bool _repeat;
+	bool _legacy, _repeat;
 }
 @end

ScryptPWGen.m

@@ -23,6 +23,7 @@
 #include <unistd.h>
 
 #import "ScryptPWGen.h"
+#import "NewPasswordGenerator.h"
 #import "LegacyPasswordGenerator.h"
 
 OF_APPLICATION_DELEGATE(ScryptPWGen)
@@ -39,6 +40,8 @@ showHelp(OFStream *output, bool verbose)
 		    @"Options:\n"
 		    @"    -h  --help    Show this help\n"
 		    @"    -l  --length  Length for the derived password\n"
+		    @"    -L  --legacy  Use the legacy algorithm "
+		    @"(compatible with scrypt-genpass)\n"
 		    @"    -r  --repeat  Repeat input\n"];
 }
 
@@ -49,13 +52,13 @@ showHelp(OFStream *output, bool verbose)
 	const of_options_parser_option_t options[] = {
 		{ 'h', @"help", 0, NULL, NULL },
 		{ 'l', @"length", 1, NULL, &lengthStr },
+		{ 'L', @"legacy", 0, &_legacy, NULL },
 		{ 'r', @"repeat", 0, &_repeat, NULL },
 		{ '\0', nil, 0, NULL, NULL }
 	};
 	OFOptionsParser *optionsParser =
 	    [OFOptionsParser parserWithOptions: options];
 	of_unichar_t option;
-	size_t length;
 	char *passphrase;
 	OFString *site, *prompt;
 
@@ -98,13 +101,33 @@ showHelp(OFStream *output, bool verbose)
 		}
 	}
 
-	if (lengthStr != nil) {
+	if ([[optionsParser remainingArguments] count] != 1) {
-		@try {
+		showHelp(of_stderr, false);
-			length = (size_t)[lengthStr decimalValue];
 
-			if (length < 3)
+		[OFApplication terminateWithStatus: 1];
-				@throw [OFInvalidFormatException exception];
+	}
+
+	site = [[optionsParser remainingArguments] firstObject];
+	prompt = [OFString stringWithFormat: @"Passphrase for site \"%@\": ",
+					     site];
+
+	id <PasswordGenerator> generator = (_legacy
+	    ? [LegacyPasswordGenerator generator]
+	    : [NewPasswordGenerator generator]);
+	generator.site = [[optionsParser remainingArguments] firstObject];
+
+	if (lengthStr != nil) {
+		bool invalid = false;
+
+		@try {
+			generator.length = (size_t)[lengthStr decimalValue];
+		} @catch (OFInvalidArgumentException *e) {
+			invalid = true;
 		} @catch (OFInvalidFormatException *e) {
+			invalid = true;
+		}
+
+		if (invalid) {
 			[of_stderr writeFormat:
 			    @"%@: Invalid length: %@\n",
 			    [OFApplication programName], lengthStr];
@@ -113,20 +136,6 @@ showHelp(OFStream *output, bool verbose)
 		}
 	}
 
-	if ([[optionsParser remainingArguments] count] != 1) {
-		showHelp(of_stderr, false);
-
-		[OFApplication terminateWithStatus: 1];
-	}
-
-	prompt = [OFString stringWithFormat: @"Passphrase for site \"%@\": ",
-					     site];
-
-	LegacyPasswordGenerator *generator =
-	    [LegacyPasswordGenerator generator];
-	generator.length = length;
-	generator.site = [[optionsParser remainingArguments] firstObject];
-
 	passphrase = getpass(
 	    [prompt cStringWithEncoding: [OFSystemInfo native8BitEncoding]]);
 	@try {