lib/cordova-ios/CordovaLib/Classes/CDVWhitelist.m - cordova-cli - Git at Google

 /*
  Licensed to the Apache Software Foundation (ASF) under one
  or more contributor license agreements.  See the NOTICE file
  distributed with this work for additional information
  regarding copyright ownership.  The ASF licenses this file
  to you under the Apache License, Version 2.0 (the
  "License"); you may not use this file except in compliance
  with the License.  You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing,
  software distributed under the License is distributed on an
  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  KIND, either express or implied.  See the License for the
  specific language governing permissions and limitations
  under the License.
  */

 #import "CDVWhitelist.h"

 NSString* const kCDVDefaultWhitelistRejectionString = @"ERROR whitelist rejection: url='%@'";
 NSString* const kCDVDefaultSchemeName = @"cdv-default-scheme";

 @interface CDVWhitelist ()

 @property (nonatomic, readwrite, strong) NSArray* whitelist;
 @property (nonatomic, readwrite, strong) NSDictionary* expandedWhitelists;

 - (void)processWhitelist;

 @end

 @implementation CDVWhitelist

 @synthesize whitelist, expandedWhitelists, whitelistRejectionFormatString;

 - (id)initWithArray:(NSArray*)array
 {
     self = [super init];
     if (self) {
         self.whitelist = array;
         self.expandedWhitelists = nil;
         self.whitelistRejectionFormatString = kCDVDefaultWhitelistRejectionString;
         [self processWhitelist];
     }

     return self;
 }

 - (BOOL)isIPv4Address:(NSString*)externalHost
 {
     // an IPv4 address has 4 octets b.b.b.b where b is a number between 0 and 255.
     // for our purposes, b can also be the wildcard character '*'

     // we could use a regex to solve this problem but then I would have two problems
     // anyways, this is much clearer and maintainable
     NSArray* octets = [externalHost componentsSeparatedByString:@"."];
     NSUInteger num_octets = [octets count];

     // quick check
     if (num_octets != 4) {
         return NO;
     }

     // restrict number parsing to 0-255
     NSNumberFormatter* numberFormatter = [[NSNumberFormatter alloc] init];
     [numberFormatter setMinimum:[NSNumber numberWithUnsignedInteger:0]];
     [numberFormatter setMaximum:[NSNumber numberWithUnsignedInteger:255]];

     // iterate through each octet, and test for a number between 0-255 or if it equals '*'
     for (NSUInteger i = 0; i < num_octets; ++i) {
         NSString* octet = [octets objectAtIndex:i];

         if ([octet isEqualToString:@"*"]) { // passes - check next octet
             continue;
         } else if ([numberFormatter numberFromString:octet] == nil) { // fails - not a number and not within our range, return
             return NO;
         }
     }

     return YES;
 }

 - (NSString*)extractHostFromUrlString:(NSString*)url
 {
     NSURL* aUrl = [NSURL URLWithString:url];

     if ((aUrl != nil) && ([aUrl scheme] != nil)) { // found scheme
         return [aUrl host];
     } else {
         return url;
     }
 }

 - (NSString*)extractSchemeFromUrlString:(NSString*)url
 {
     NSURL* aUrl = [NSURL URLWithString:url];

     if ((aUrl != nil) && ([aUrl scheme] != nil)) { // found scheme
         return [aUrl scheme];
     } else {
         return kCDVDefaultSchemeName;
     }
 }

 - (void)processWhitelist
 {
     if (self.whitelist == nil) {
         NSLog(@"ERROR: CDVWhitelist was not initialized properly, all urls will be disallowed.");
         return;
     }

     NSMutableDictionary* _expandedWhitelists = [@{kCDVDefaultSchemeName: [NSMutableArray array]} mutableCopy];

     // only allow known TLDs (since Aug 23rd 2011), and two character country codes
     // does not match internationalized domain names with non-ASCII characters
     NSString* tld_match = @"(aero|asia|arpa|biz|cat|com|coop|edu|gov|info|int|jobs|mil|mobi|museum|name|net|org|pro|tel|travel|xxx|[a-z][a-z])";

     // iterate through settings ExternalHosts, check for equality
     for (NSString* externalHost in self.whitelist) {
         NSString* host = [self extractHostFromUrlString:externalHost];
         NSString* scheme = [self extractSchemeFromUrlString:externalHost];

         // check for single wildcard '*', if found set allowAll to YES
         if ([host isEqualToString:@"*"]) {
             [_expandedWhitelists setObject:[NSArray arrayWithObject:host] forKey:scheme];
             continue;
         }

         // if this is the first value for this scheme, create a new entry
         if ([_expandedWhitelists objectForKey:scheme] == nil) {
             [_expandedWhitelists setObject:[NSMutableArray array] forKey:scheme];
         }

         // starts with wildcard match - we make the first '.' optional (so '*.org.apache.cordova' will match 'org.apache.cordova')
         NSString* prefix = @"*.";
         if ([host hasPrefix:prefix]) {
             // replace the first two characters '*.' with our regex
             host = [host stringByReplacingCharactersInRange:NSMakeRange(0, [prefix length]) withString:@"(\\s{0}|*.)"]; // the '*' and '.' will be substituted later
         }

         // ends with wildcard match for TLD
         if (![self isIPv4Address:host] && [host hasSuffix:@".*"]) {
             // replace * with tld_match
             host = [host stringByReplacingCharactersInRange:NSMakeRange([host length] - 1, 1) withString:tld_match];
         }
         // escape periods - since '.' means any character in regex
         host = [host stringByReplacingOccurrencesOfString:@"." withString:@"\\."];
         // wildcard is match 1 or more characters (to make it simple, since we are not doing verification whether the hostname is valid)
         host = [host stringByReplacingOccurrencesOfString:@"*" withString:@".*"];

         [[_expandedWhitelists objectForKey:scheme] addObject:host];
     }

     self.expandedWhitelists = _expandedWhitelists;
 }

 - (BOOL)schemeIsAllowed:(NSString*)scheme
 {
     if ([scheme isEqualToString:@"http"] ||
         [scheme isEqualToString:@"https"] ||
         [scheme isEqualToString:@"ftp"] ||
         [scheme isEqualToString:@"ftps"]) {
         return YES;
     }

     return (self.expandedWhitelists != nil) && ([self.expandedWhitelists objectForKey:scheme] != nil);
 }

 - (BOOL)URLIsAllowed:(NSURL*)url
 {
     NSString* scheme = [url scheme];

     // http[s] and ftp[s] should also validate against the common set in the kCDVDefaultSchemeName list
     if ([scheme isEqualToString:@"http"] || [scheme isEqualToString:@"https"] || [scheme isEqualToString:@"ftp"] || [scheme isEqualToString:@"ftps"]) {
         NSURL* newUrl = [NSURL URLWithString:[NSString stringWithFormat:@"%@://%@", kCDVDefaultSchemeName, [url host]]];
         // If it is allowed, we are done.  If not, continue to check for the actual scheme-specific list
         if ([self URLIsAllowed:newUrl]) {
             return YES;
         }
     }

     // Check that the scheme is supported
     if (![self schemeIsAllowed:scheme]) {
         return NO;
     }

     NSArray* expandedWhitelist = [self.expandedWhitelists objectForKey:scheme];

     // Are we allowing everything for this scheme?
     // TODO: consider just having a static sentinel value for the "allow all" list, so we can use object equality
     if (([expandedWhitelist count] == 1) && [[expandedWhitelist objectAtIndex:0] isEqualToString:@"*"]) {
         return YES;
     }

     // iterate through settings ExternalHosts, check for equality
     NSEnumerator* enumerator = [expandedWhitelist objectEnumerator];
     id regex = nil;
     NSString* urlHost = [url host];

     // if the url host IS found in the whitelist, load it in the app (however UIWebViewNavigationTypeOther kicks it out to Safari)
     // if the url host IS NOT found in the whitelist, we do nothing
     while (regex = [enumerator nextObject]) {
         NSPredicate* regex_test = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];

         if ([regex_test evaluateWithObject:urlHost] == YES) {
             // if it matches at least one rule, return
             return YES;
         }
     }

     NSLog(@"%@", [self errorStringForURL:url]);
     // if we got here, the url host is not in the white-list, do nothing
     return NO;
 }

 - (NSString*)errorStringForURL:(NSURL*)url
 {
     return [NSString stringWithFormat:self.whitelistRejectionFormatString, [url absoluteString]];
 }

 @end
	/*
	Licensed to the Apache Software Foundation (ASF) under one
	or more contributor license agreements. See the NOTICE file
	distributed with this work for additional information
	regarding copyright ownership. The ASF licenses this file
	to you under the Apache License, Version 2.0 (the
	"License"); you may not use this file except in compliance
	with the License. You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing,
	software distributed under the License is distributed on an
	"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	KIND, either express or implied. See the License for the
	specific language governing permissions and limitations
	under the License.
	*/

	#import "CDVWhitelist.h"

	NSString* const kCDVDefaultWhitelistRejectionString = @"ERROR whitelist rejection: url='%@'";
	NSString* const kCDVDefaultSchemeName = @"cdv-default-scheme";

	@interface CDVWhitelist ()

	@property (nonatomic, readwrite, strong) NSArray* whitelist;
	@property (nonatomic, readwrite, strong) NSDictionary* expandedWhitelists;

	- (void)processWhitelist;

	@end

	@implementation CDVWhitelist

	@synthesize whitelist, expandedWhitelists, whitelistRejectionFormatString;

	- (id)initWithArray:(NSArray*)array
	{
	self = [super init];
	if (self) {
	self.whitelist = array;
	self.expandedWhitelists = nil;
	self.whitelistRejectionFormatString = kCDVDefaultWhitelistRejectionString;
	[self processWhitelist];
	}

	return self;
	}

	- (BOOL)isIPv4Address:(NSString*)externalHost
	{
	// an IPv4 address has 4 octets b.b.b.b where b is a number between 0 and 255.
	// for our purposes, b can also be the wildcard character '*'

	// we could use a regex to solve this problem but then I would have two problems
	// anyways, this is much clearer and maintainable
	NSArray* octets = [externalHost componentsSeparatedByString:@"."];
	NSUInteger num_octets = [octets count];

	// quick check
	if (num_octets != 4) {
	return NO;
	}

	// restrict number parsing to 0-255
	NSNumberFormatter* numberFormatter = [[NSNumberFormatter alloc] init];
	[numberFormatter setMinimum:[NSNumber numberWithUnsignedInteger:0]];
	[numberFormatter setMaximum:[NSNumber numberWithUnsignedInteger:255]];

	// iterate through each octet, and test for a number between 0-255 or if it equals '*'
	for (NSUInteger i = 0; i < num_octets; ++i) {
	NSString* octet = [octets objectAtIndex:i];

	if ([octet isEqualToString:@"*"]) { // passes - check next octet
	continue;
	} else if ([numberFormatter numberFromString:octet] == nil) { // fails - not a number and not within our range, return
	return NO;
	}
	}

	return YES;
	}

	- (NSString)extractHostFromUrlString:(NSString)url
	{
	NSURL* aUrl = [NSURL URLWithString:url];

	if ((aUrl != nil) && ([aUrl scheme] != nil)) { // found scheme
	return [aUrl host];
	} else {
	return url;
	}
	}

	- (NSString)extractSchemeFromUrlString:(NSString)url
	{
	NSURL* aUrl = [NSURL URLWithString:url];

	if ((aUrl != nil) && ([aUrl scheme] != nil)) { // found scheme
	return [aUrl scheme];
	} else {
	return kCDVDefaultSchemeName;
	}
	}

	- (void)processWhitelist
	{
	if (self.whitelist == nil) {
	NSLog(@"ERROR: CDVWhitelist was not initialized properly, all urls will be disallowed.");
	return;
	}

	NSMutableDictionary* _expandedWhitelists = [@{kCDVDefaultSchemeName: [NSMutableArray array]} mutableCopy];

	// only allow known TLDs (since Aug 23rd 2011), and two character country codes
	// does not match internationalized domain names with non-ASCII characters
	NSString* tld_match = @"(aero\|asia\|arpa\|biz\|cat\|com\|coop\|edu\|gov\|info\|int\|jobs\|mil\|mobi\|museum\|name\|net\|org\|pro\|tel\|travel\|xxx\|[a-z][a-z])";

	// iterate through settings ExternalHosts, check for equality
	for (NSString* externalHost in self.whitelist) {
	NSString* host = [self extractHostFromUrlString:externalHost];
	NSString* scheme = [self extractSchemeFromUrlString:externalHost];

	// check for single wildcard '*', if found set allowAll to YES
	if ([host isEqualToString:@"*"]) {
	[_expandedWhitelists setObject:[NSArray arrayWithObject:host] forKey:scheme];
	continue;
	}

	// if this is the first value for this scheme, create a new entry
	if ([_expandedWhitelists objectForKey:scheme] == nil) {
	[_expandedWhitelists setObject:[NSMutableArray array] forKey:scheme];
	}

	// starts with wildcard match - we make the first '.' optional (so '*.org.apache.cordova' will match 'org.apache.cordova')
	NSString* prefix = @"*.";
	if ([host hasPrefix:prefix]) {
	// replace the first two characters '*.' with our regex
	host = [host stringByReplacingCharactersInRange:NSMakeRange(0, [prefix length]) withString:@"(\\s{0}\|.)"]; // the '' and '.' will be substituted later
	}

	// ends with wildcard match for TLD
	if (![self isIPv4Address:host] && [host hasSuffix:@".*"]) {
	// replace * with tld_match
	host = [host stringByReplacingCharactersInRange:NSMakeRange([host length] - 1, 1) withString:tld_match];
	}
	// escape periods - since '.' means any character in regex
	host = [host stringByReplacingOccurrencesOfString:@"." withString:@"\\."];
	// wildcard is match 1 or more characters (to make it simple, since we are not doing verification whether the hostname is valid)
	host = [host stringByReplacingOccurrencesOfString:@"" withString:@"."];

	[[_expandedWhitelists objectForKey:scheme] addObject:host];
	}

	self.expandedWhitelists = _expandedWhitelists;
	}

	- (BOOL)schemeIsAllowed:(NSString*)scheme
	{
	if ([scheme isEqualToString:@"http"] \|\|
	[scheme isEqualToString:@"https"] \|\|
	[scheme isEqualToString:@"ftp"] \|\|
	[scheme isEqualToString:@"ftps"]) {
	return YES;
	}

	return (self.expandedWhitelists != nil) && ([self.expandedWhitelists objectForKey:scheme] != nil);
	}

	- (BOOL)URLIsAllowed:(NSURL*)url
	{
	NSString* scheme = [url scheme];

	// http[s] and ftp[s] should also validate against the common set in the kCDVDefaultSchemeName list
	if ([scheme isEqualToString:@"http"] \|\| [scheme isEqualToString:@"https"] \|\| [scheme isEqualToString:@"ftp"] \|\| [scheme isEqualToString:@"ftps"]) {
	NSURL* newUrl = [NSURL URLWithString:[NSString stringWithFormat:@"%@://%@", kCDVDefaultSchemeName, [url host]]];
	// If it is allowed, we are done. If not, continue to check for the actual scheme-specific list
	if ([self URLIsAllowed:newUrl]) {
	return YES;
	}
	}

	// Check that the scheme is supported
	if (![self schemeIsAllowed:scheme]) {
	return NO;
	}

	NSArray* expandedWhitelist = [self.expandedWhitelists objectForKey:scheme];

	// Are we allowing everything for this scheme?
	// TODO: consider just having a static sentinel value for the "allow all" list, so we can use object equality
	if (([expandedWhitelist count] == 1) && [[expandedWhitelist objectAtIndex:0] isEqualToString:@"*"]) {
	return YES;
	}

	// iterate through settings ExternalHosts, check for equality
	NSEnumerator* enumerator = [expandedWhitelist objectEnumerator];
	id regex = nil;
	NSString* urlHost = [url host];

	// if the url host IS found in the whitelist, load it in the app (however UIWebViewNavigationTypeOther kicks it out to Safari)
	// if the url host IS NOT found in the whitelist, we do nothing
	while (regex = [enumerator nextObject]) {
	NSPredicate* regex_test = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];

	if ([regex_test evaluateWithObject:urlHost] == YES) {
	// if it matches at least one rule, return
	return YES;
	}
	}

	NSLog(@"%@", [self errorStringForURL:url]);
	// if we got here, the url host is not in the white-list, do nothing
	return NO;
	}

	- (NSString)errorStringForURL:(NSURL)url
	{
	return [NSString stringWithFormat:self.whitelistRejectionFormatString, [url absoluteString]];
	}

	@end