Re: openssl_encrypt, ecb and IV

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Am 24.01.2013 18:08, schrieb Kevin Kinsey:
On Thu, Jan 24, 2013 at 05:55:35PM +0100, steffo76@xxxxxx wrote:
Hi list,

I am having trouble with error messages saying
"Using an empty Initialization Vector (iv) is potentially insecure and not recommended"

These messages turn up using horde which uses ecb. I don't know the inner workings of php and openssl but if I understand correctly, there is no IV used in ecb hence there should be no error message according to this:
http://svn.php.net/viewvc?view=revision&revision=304179
(I am running php version 5.3.20)

Does anybody have any idea why I am getting these errors ? I can reproduce them using this code:

<?php
openssl_encrypt ("Hallo","bf-ecb","abcdef");
?>

Regards
Stephan

Because E_WARNING is issued if the optional fourth parameter, Initialization
Vector, is NULL.

Is that so ? In ext/openssl/openssl.c it looks like php is questioning openssl if the cipher in question needs an iv by calling EVP_CIPHER_iv_length which according to its manpage returns 0 if the cipher does not use an iv. If I understand correctly the warning only gets thrown if the vector is needed and empty. Since ecb does not need an iv this warning should not appear at all, should it ? This is also how I understand the log for the code change:

http://svn.php.net/viewvc?view=revision&revision=304179

How exactly are the error messages troubling you?  If they're appearing on
your site/pages, you should adjust server or site configuration.

That is what I did as a workaround but the question remains why I keep getting the warning with recent versions of php. It doesn't matter if I compile php against the 0.9.8 or the 1.0.1 versions of openssl.

Thanks
Stephan


--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php



[Index of Archives]     [PHP Home]     [Apache Users]     [PHP on Windows]     [Kernel Newbies]     [PHP Install]     [PHP Classes]     [Pear]     [Postgresql]     [Postgresql PHP]     [PHP on Windows]     [PHP Database Programming]     [PHP SOAP]

  Powered by Linux