Feature #9613: Warn about unsafe ossl ciphers

• Status: Open
• Assignee: -
• Target version: -

[zzak (zzak _)]

As of r45274, we now have sane whitelist of available OpenSSL ciphers. However, this patch breaks backwards compatibility for any apps that use any ciphers not whitelisted.

Solution

• Implement a new class: OpenSSL::SSL::Ciphers
  • This class defines a constant for every whitelisted cipher used by DEFAULT_PARAMS[:ciphers]
  • Any constant not found within this class should raise a warning and report to the user
• Add an OpenSSL::SSL::Configuration class
  • Designed to default to no compression, and no sslv2/v3
  • Used by DEFAULT_PARAMS[:options]
  • This class may contain helper methods such as: #compression_enabled?

Pros

• We don't break anything, without warning users first
• Maintaining future whitelist ciphers is easier
• Future unsupported/blacklist ciphers are already dismissed
• Users are able to extend cipher lists to support their needs (by adding a constant to OpenSSL::SSL::Ciphers)

Concerns

I have discussed this with Martin, and we'd like to open up this discussion for feedback. We're particularly concerned about backporting r45274 as it breaks compatibility. We should also consider:

• Do we backport both patches or just the warning?
• Should we bother backporting deprecation warnings?
  • Since r45274 is not a security fix, do we consider this a bug?
  • Rails only introduces deprecation notices in new minor releases (ie: Ruby-2.2.0)
• r45274 is a major change that could break existing apps, even considering security

[naruse (Yui NARUSE)]

• Related to Backport #9640: Please backport SSL fixes to 2.1 added

[zeha (Christian Hofstaedtler)]

Single datapoint: r45274 will likely end up in Debian jessie's ruby 2.1, and by extension probably in Ubuntu's ruby 2.1.

[zzak (zzak _)]

• Tracker changed from Bug to Feature
• Assignee set to 7150