Timing Attack Vulnerability

[paragonie-scott]

http://www.openwall.com/lists/oss-security/2016/01/24/10

• https://github.com/RNCryptor/RNCryptor-Spec/blob/04378bc27c604e97353badbead8c435698abe97a/RNCryptor-Spec-v3.md#consistent-time-equality-checking
• https://cryptocoding.net/index.php/Coding_rules#Compare_secret_strings_in_constant_time
• http://blog.ircmaxell.com/2014/11/its-all-about-time.html

Problematic line:

ruby_rncryptor/lib/ruby_rncryptor.rb

Line 27 in 5fff939

verified = [HMAC.hexdigest('sha256', hmac_key, msg)].pack('H*') == hmac

[timestretch]

Thanks for the report! I just pushed v3.0.1 which uses the eql_time_cmp method from the openssl docs.