How to decrypt the iPhone encrypted AES256 text in PHP

Question

I would like to know how to decrypt some text encrypted on iPhone using AES256 and PKCS7Padding with a PHP function.

I use following Objective-C code.

https://gist.github.com/838614

- (NSString *)AES256EncryptWithKey:(NSString *)key
{
   NSData *plainData = [self dataUsingEncoding:NSUTF8StringEncoding];
   NSData *encryptedData = [plainData AES256EncryptWithKey:key];

   NSString *encryptedString = [encryptedData base64Encoding];

   return encryptedString;
}

score 2 · Answer 1 · edited May 23 '17 at 09:58

2

The following PHP snippet covers removing PKCS7 padding, which combined with this SO question (but substituting MCRYPT_RIJNDAEL_128 for MCRYPT_RIJNDAEL_256 in your case) should give you what you need.

edited May 23 '17 at 09:58

Community

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answered Mar 21 '11 at 12:17

jnic

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just a little question, in iOS code, we don't really have $iv kind of value in. what does it really mean.. and also about block size parameter to unpad.. thanks a lot for your help... – Tharindu Madushanka Mar 21 '11 at 12:59
The IV in this case is the 6th argument to CCCrypt (line 48). More about IVs at Wikipedia (http://en.wikipedia.org/wiki/Initialization_vector). The block size appears to be kCCBlockSizeAES128. – jnic Mar 21 '11 at 16:22

How to decrypt the iPhone encrypted AES256 text in PHP

1 Answers1