Added NSUInteger overflow checks

Signed-off-by: Dave Poirier <[email protected]>

Base64.podspec

@@ -1,11 +1,11 @@
 Pod::Spec.new do |s|
   s.name     = 'Base64'
-  s.version  = '1.1.1'
+  s.version  = '1.1.2'
   s.license  = 'Public Domain'
   s.summary  = 'RFC 4648 Base64 implementation in Objective-C ARC.'
   s.homepage = 'https://github.com/ekscrypto/Base64'
   s.author   = { 'Dave Poirier' => '[email protected]' }
-  s.source   = { :git => 'https://github.com/ekscrypto/Base64.git', :tag => '1.1.1' }
+  s.source   = { :git => 'https://github.com/ekscrypto/Base64.git', :tag => '1.1.2' }
   s.source_files = 'Classes', 'Base64/MF_Base64Additions.{h,m}'
   s.requires_arc = true
 end

Base64/MF_Base64Additions.m

@@ -70,6 +70,7 @@ +(NSData *)dataFromBase64String:(NSString *)encoding
         unsigned char *encodedBytes = (unsigned char *)[encodedData bytes];
 
         NSUInteger encodedLength = [encodedData length];
+        if( encodedLength >= (NSUIntegerMax - 3) ) return nil; // NSUInteger overflow check
         NSUInteger encodedBlocks = (encodedLength+3) >> 2;
         NSUInteger expectedDataLength = encodedBlocks * 3;
 
@@ -150,7 +151,8 @@ +(NSString *)base64StringFromData:(NSData *)data
         //       16 Q            33 h            50 y
 
         NSUInteger dataLength = [data length];
-        NSUInteger encodedBlocks = (dataLength * 8) / 24;
+        NSUInteger encodedBlocks = dataLength / 3;
+        if( (encodedBlocks + 1) >= (NSUIntegerMax / 4) ) return nil; // NSUInteger overflow check
         NSUInteger padding = paddingTable[dataLength % 3];
         if( padding > 0 ) encodedBlocks++;
         NSUInteger encodedLength = encodedBlocks * 4;