Which is somewhat confusing again, as I thought PHP could deal with decryption with the entire text, not just block-by-block.
Perhaps the encryption is meant to be decrypted block by block.. with some sequential encryption methods the actual encryption changes for each block, which could be designated as a sequential number by the IV. Lets say its just "1" - the first block is encrypted with "1" then next with "2" and so on? I'm just getting into encryption myself - new hobby of the day - so feel free to crush my theories plz
I may be wrong: There may be other perl encryption methods that include this header.
Perhaps someone modified an existing method in their own way, to create a unique custom encryption method.
So I went and google searched the string for Random IV "52616e646f6d4956" - I found a couple of links that might help.http://efreedom.com/Question/1-1864700/Part-II-Make-Ruby-AES-256-CBC-PHP-MCRYPT-RIJNDAEL-128-Play-Togetherhttp://efreedom.com/Question/1-2608234/Encrypting-Perl-CBC-Decrypting-PHP-Mcrypt
I am going to play with this myself, I find encryption to be quite fun and interesting, I just need to learn ALOT more.