PHP OpenSSL Encrypt Issue

Question

So I'm trying to encrypt and echo a file with openssl. Getting my file contents works, but after I call the function to encrypt, it doesn't echo anything, as if it were a syntax error.

$file = file_get_contents($filename);
//echo $file; // works
$encfile = openssl_encrypt($file, $encmethod, $enckey, 0, $iv);
echo $encfile;

Yes, all my encryption keys and everything are valid. Echoing anything after the encryption doesn't work. If anyone knows what's wrong please let me know.

Tell us, what are the values of `$encmethod`, and `$iv`. Also, what is the **byte length** of `$enckey`? Also as requested, check your error log. — Matt Clark, Apr 05 '18 at 01:04
Do you [even have OpenSSL installed with PHP](https://stackoverflow.com/questions/11525524/why-cant-i-use-openssl-encrypt)? — Matt Clark, Apr 05 '18 at 01:05
@MattClark `$encmethod = "AES-256-CBC";` $iv is 16 bytes $enckey is 32 and theyre based off of time and worked fine with a smaller file previously. — , Apr 05 '18 at 01:06
so, what did the logs reveal after what @zerk asked , *anything?* If you don't have access to logs, then set error reporting to catch and display. What version of PHP also? — Funk Forty Niner, Apr 05 '18 at 01:22
@FunkFortyNiner `PHP Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 14554477 bytes) in /var/www/html/test.php on line 121: /usr/local/cpanel/cgi-sys/ea-php56` So I'm assuming the file size is too large. I guess I will need to allow PHP more memory. — , Apr 05 '18 at 01:29
Probably, or you need to find out if there are too many resources running. That, and try increasing it and the max upload file in the .ini files. — Funk Forty Niner, Apr 05 '18 at 01:31

score 1 · Answer 1 · answered Apr 05 '18 at 01:35

1

I allowed php more memory with

ini_set('memory_limit','512M');

And now it works like a charm.

answered Apr 05 '18 at 01:35

I use `ini_set('memory_limit','3G');` on my server lol, really. But it was only for one time, Ususall PHP only has `1G` but I had to pull 130million rows out of the DB and move them to MongoDB ... lol – ArtisticPhoenix Apr 05 '18 at 01:43

ArtisticPhoenix · Answer 2 · 2018-04-05T01:47:04.313

I wouldn't add more memory.

I faced a similar issue recently.

How did I fix it, I encrypted chunks of the file at a time a few MB, then I separated the base64 encoded chunks with a : which doesn't appear in base64.

Then when you decode it you read it tell you get the the : decrypt it and move on to the next chunk.

That way you stay well below the memory limit ... :)

See this answer I posted a few days ago KLICK

-note- I use PHPSecLib for AES, we were already using it for sFTP, and I had to update from mycrypt for our Upcoming move to PHP7.

PHP OpenSSL Encrypt Issue

2 Answers2