@@ -34,37 +34,54 @@
 #import "OFInvalidArgumentException.h"
 #import "OFInvalidFormatException.h"
 #import "OFOutOfMemoryException.h"
 
 static OFCharacterSet *URLAllowedCharacterSet = nil;
+static OFCharacterSet *URLSchemeAllowedCharacterSet = nil;
 static OFCharacterSet *URLPathAllowedCharacterSet = nil;
 static OFCharacterSet *URLQueryOrFragmentAllowedCharacterSet = nil;
 
-@interface OFCharacterSet_URLAllowed: OFCharacterSet
+@interface OFCharacterSet_URLAllowedBase: OFCharacterSet
+- (instancetype)of_init OF_METHOD_FAMILY(init);
+@end
+
+@interface OFCharacterSet_URLAllowed: OFCharacterSet_URLAllowedBase
 + (OFCharacterSet *)URLAllowedCharacterSet;
 @end
 
-@interface OFCharacterSet_URLPathAllowed: OFCharacterSet
+@interface OFCharacterSet_URLSchemeAllowed: OFCharacterSet_URLAllowedBase
++ (OFCharacterSet *)URLSchemeAllowedCharacterSet;
+@end
+
+@interface OFCharacterSet_URLPathAllowed: OFCharacterSet_URLAllowedBase
 + (OFCharacterSet *)URLPathAllowedCharacterSet;
 @end
 
-@interface OFCharacterSet_URLQueryOrFragmentAllowed: OFCharacterSet
+@interface OFCharacterSet_URLQueryOrFragmentAllowed:
+    OFCharacterSet_URLAllowedBase
 + (OFCharacterSet *)URLQueryOrFragmentAllowedCharacterSet;
 @end
 
-@implementation OFCharacterSet_URLAllowed
-+ (void)initialize
+@interface OFCharacterSet_invertedSetWithPercent: OFCharacterSet
 {
-	if (self != [OFCharacterSet_URLAllowed class])
-		return;
-
-	URLAllowedCharacterSet = [[OFCharacterSet_URLAllowed alloc] init];
+	OFCharacterSet *_characterSet;
+	bool (*_characterIsMember)(id, SEL, of_unichar_t);
 }
 
-+ (OFCharacterSet *)URLAllowedCharacterSet
+- (instancetype)of_initWithCharacterSet: (OFCharacterSet *)characterSet
+    OF_METHOD_FAMILY(init);
+@end
+
+@implementation OFCharacterSet_URLAllowedBase
+- (instancetype)init
 {
-	return URLAllowedCharacterSet;
+	OF_INVALID_INIT_METHOD
+}
+
+- (instancetype)of_init
+{
+	return [super init];
 }
 
 - (instancetype)autorelease
 {
 	return self;
@@ -81,10 +98,25 @@
 
 - (unsigned int)retainCount
 {
 	return OF_RETAIN_COUNT_MAX;
 }
+@end
+
+@implementation OFCharacterSet_URLAllowed
++ (void)initialize
+{
+	if (self != [OFCharacterSet_URLAllowed class])
+		return;
+
+	URLAllowedCharacterSet = [[OFCharacterSet_URLAllowed alloc] of_init];
+}
+
++ (OFCharacterSet *)URLAllowedCharacterSet
+{
+	return URLAllowedCharacterSet;
+}
 
 - (bool)characterIsMember: (of_unichar_t)character
 {
 	if (character < CHAR_MAX && of_ascii_isalnum(character))
 		return true;
@@ -109,45 +141,57 @@
 	default:
 		return false;
 	}
 }
 @end
+
+@implementation OFCharacterSet_URLSchemeAllowed
++ (void)initialize
+{
+	if (self != [OFCharacterSet_URLSchemeAllowed class])
+		return;
+
+	URLSchemeAllowedCharacterSet =
+	    [[OFCharacterSet_URLSchemeAllowed alloc] of_init];
+}
+
++ (OFCharacterSet *)URLSchemeAllowedCharacterSet
+{
+	return URLSchemeAllowedCharacterSet;
+}
+
+- (bool)characterIsMember: (of_unichar_t)character
+{
+	if (character < CHAR_MAX && of_ascii_isalnum(character))
+		return true;
+
+	switch (character) {
+	case '+':
+	case '-':
+	case '.':
+		return true;
+	default:
+		return false;
+	}
+}
+@end
 
 @implementation OFCharacterSet_URLPathAllowed
 + (void)initialize
 {
 	if (self != [OFCharacterSet_URLPathAllowed class])
 		return;
 
 	URLPathAllowedCharacterSet =
-	    [[OFCharacterSet_URLPathAllowed alloc] init];
+	    [[OFCharacterSet_URLPathAllowed alloc] of_init];
 }
 
 + (OFCharacterSet *)URLPathAllowedCharacterSet
 {
 	return URLPathAllowedCharacterSet;
 }
 
-- (instancetype)autorelease
-{
-	return self;
-}
-
-- (instancetype)retain
-{
-	return self;
-}
-
-- (void)release
-{
-}
-
-- (unsigned int)retainCount
-{
-	return OF_RETAIN_COUNT_MAX;
-}
-
 - (bool)characterIsMember: (of_unichar_t)character
 {
 	if (character < CHAR_MAX && of_ascii_isalnum(character))
 		return true;
 
@@ -182,37 +226,18 @@
 {
 	if (self != [OFCharacterSet_URLQueryOrFragmentAllowed class])
 		return;
 
 	URLQueryOrFragmentAllowedCharacterSet =
-	    [[OFCharacterSet_URLQueryOrFragmentAllowed alloc] init];
+	    [[OFCharacterSet_URLQueryOrFragmentAllowed alloc] of_init];
 }
 
 + (OFCharacterSet *)URLQueryOrFragmentAllowedCharacterSet
 {
 	return URLQueryOrFragmentAllowedCharacterSet;
 }
 
-- (instancetype)autorelease
-{
-	return self;
-}
-
-- (instancetype)retain
-{
-	return self;
-}
-
-- (void)release
-{
-}
-
-- (unsigned int)retainCount
-{
-	return OF_RETAIN_COUNT_MAX;
-}
-
 - (bool)characterIsMember: (of_unichar_t)character
 {
 	if (character < CHAR_MAX && of_ascii_isalnum(character))
 		return true;
 
@@ -240,15 +265,60 @@
 	default:
 		return false;
 	}
 }
 @end
+
+@implementation OFCharacterSet_invertedSetWithPercent
+- (instancetype)init
+{
+	OF_INVALID_INIT_METHOD
+}
+
+- (instancetype)of_initWithCharacterSet: (OFCharacterSet *)characterSet
+{
+	self = [super init];
+
+	_characterSet = [characterSet retain];
+	_characterIsMember = (bool (*)(id, SEL, of_unichar_t))
+	    [_characterSet methodForSelector: @selector(characterIsMember:)];
+
+	return self;
+}
+
+- (void)dealloc
+{
+	[_characterSet release];
+
+	[super dealloc];
+}
+
+- (bool)characterIsMember: (of_unichar_t)character
+{
+	return (character != '%' && !_characterIsMember(_characterSet,
+	    @selector(characterIsMember:), character));
+}
+@end
+
+void
+of_url_verify_escaped(OFString *string, OFCharacterSet *characterSet)
+{
+	void *pool = objc_autoreleasePoolPush();
+
+	characterSet = [[[OFCharacterSet_invertedSetWithPercent alloc]
+	    of_initWithCharacterSet: characterSet] autorelease];
+
+	if ([string indexOfCharacterFromSet: characterSet] != OF_NOT_FOUND)
+		@throw [OFInvalidFormatException exception];
+
+	objc_autoreleasePoolPop(pool);
+}
 
 @implementation OFCharacterSet (URLCharacterSets)
 + (OFCharacterSet *)URLSchemeAllowedCharacterSet
 {
-	return [OFCharacterSet_URLAllowed URLAllowedCharacterSet];
+	return [OFCharacterSet_URLSchemeAllowed URLSchemeAllowedCharacterSet];
 }
 
 + (OFCharacterSet *)URLHostAllowedCharacterSet
 {
 	return [OFCharacterSet_URLAllowed URLAllowedCharacterSet];
@@ -352,10 +422,13 @@
 
 		_URLEncodedScheme = [[OFString alloc]
 		    initWithUTF8String: UTF8String
 				length: tmp - UTF8String];
 
+		of_url_verify_escaped(_URLEncodedScheme,
+		    [OFCharacterSet URLSchemeAllowedCharacterSet]);
+
 		UTF8String = tmp + 3;
 
 		if ((tmp = strchr(UTF8String, '/')) != NULL) {
 			*tmp = '\0';
 			tmp++;
@@ -373,14 +446,21 @@
 
 				_URLEncodedUser = [[OFString alloc]
 				    initWithUTF8String: UTF8String];
 				_URLEncodedPassword = [[OFString alloc]
 				    initWithUTF8String: tmp3];
+
+				of_url_verify_escaped(_URLEncodedPassword,
+				    [OFCharacterSet
+				    URLPasswordAllowedCharacterSet]);
 			} else
 				_URLEncodedUser = [[OFString alloc]
 				    initWithUTF8String: UTF8String];
 
+			of_url_verify_escaped(_URLEncodedUser,
+			    [OFCharacterSet URLUserAllowedCharacterSet]);
+
 			UTF8String = tmp2;
 		}
 
 		if ((tmp2 = strchr(UTF8String, ':')) != NULL) {
 			OFString *portString;
@@ -400,30 +480,44 @@
 			    (uint16_t)[portString decimalValue]];
 		} else
 			_URLEncodedHost = [[OFString alloc]
 			    initWithUTF8String: UTF8String];
 
+		of_url_verify_escaped(_URLEncodedHost,
+		    [OFCharacterSet URLHostAllowedCharacterSet]);
+
 		if ((UTF8String = tmp) != NULL) {
 			if ((tmp = strchr(UTF8String, '#')) != NULL) {
 				*tmp = '\0';
 
 				_URLEncodedFragment = [[OFString alloc]
 				    initWithUTF8String: tmp + 1];
+
+				of_url_verify_escaped(_URLEncodedFragment,
+				    [OFCharacterSet
+				    URLFragmentAllowedCharacterSet]);
 			}
 
 			if ((tmp = strchr(UTF8String, '?')) != NULL) {
 				*tmp = '\0';
 
 				_URLEncodedQuery = [[OFString alloc]
 				    initWithUTF8String: tmp + 1];
+
+				of_url_verify_escaped(_URLEncodedQuery,
+				    [OFCharacterSet
+				    URLQueryAllowedCharacterSet]);
 			}
 
 			UTF8String--;
 			*UTF8String = '/';
 
 			_URLEncodedPath = [[OFString alloc]
 			    initWithUTF8String: UTF8String];
+
+			of_url_verify_escaped(_URLEncodedPath,
+			    [OFCharacterSet URLPathAllowedCharacterSet]);
 		}
 
 		objc_autoreleasePoolPop(pool);
 	} @catch (id e) {
 		[self release];
@@ -464,16 +558,22 @@
 
 		if ((tmp = strchr(UTF8String, '#')) != NULL) {
 			*tmp = '\0';
 			_URLEncodedFragment = [[OFString alloc]
 			    initWithUTF8String: tmp + 1];
+
+			of_url_verify_escaped(_URLEncodedFragment,
+			    [OFCharacterSet URLFragmentAllowedCharacterSet]);
 		}
 
 		if ((tmp = strchr(UTF8String, '?')) != NULL) {
 			*tmp = '\0';
 			_URLEncodedQuery = [[OFString alloc]
 			    initWithUTF8String: tmp + 1];
+
+			of_url_verify_escaped(_URLEncodedQuery,
+			    [OFCharacterSet URLQueryAllowedCharacterSet]);
 		}
 
 		if (*UTF8String == '/')
 			_URLEncodedPath = [[OFString alloc]
 			    initWithUTF8String: UTF8String];
@@ -491,10 +591,13 @@
 
 			_URLEncodedPath =
 			    [[s stringByStandardizingURLPath] copy];
 		}
 
+		of_url_verify_escaped(_URLEncodedPath,
+		    [OFCharacterSet URLPathAllowedCharacterSet]);
+
 		objc_autoreleasePoolPop(pool);
 	} @catch (id e) {
 		[self release];
 		@throw e;
 	} @finally {