On Sat, Feb 28, 2015 at 02:28:17PM -0500, Jeffrey Altman wrote: > On 2/27/2015 3:26 PM, Benjamin Kaduk wrote: > > One change which has been proposed is to encrypt connections by default. > > There has long been the 'fs setcrypt' command (introduced in 2001) to > > allow the connections from a cache manager to the servers in the cell > > (which most distributions' packaging enable by default). However, there > > is not currently an option to enable encryption for the intra-dbserver > > connections which effect ubik replication, or for other server-to-server > > connections such as fileserver queries to the protection server, and > > volume forwarding traffic. > > > > Given events in the news in recent years, it seems to me that we do our > > users a disservice by not using a "secure" mode operation by default. > > Agreed. I am particularly troubled by the lack of wire privacy mode > used for volume transfers and since organizations replicate volume data > across the public Internet between sites and it never occurs to them > that this data might be sent in the clear.
Agreed. It is particularly irritating to have to set up a VPN to replicate volume data. It would be a particularly compelling market advantage of AFS to be able to advertise that all connections are encrypted by default, and *only* the Kerberos server has access to the keys. (I am not a fan of the https/ssl public/private key model where any attacker can buy a root cert, or pre-install it on laptops) Someday I would like to see per-file (or maybe per-volume) encryption keys, and keep the decryption keys separate from the data. That might actually require public/private keys to do correctly. > > (Quote around "secure" are necessary given the known weaknesses of the > > fcrypt encryption used by rxkad, but with the rxkad-k5 extension, there > > does remain some level of protection to offer.) Though rxkad encryption > > is known to introduce severe performance penalties, administrators who > > require the extra performance should be able to discover that and use > > the documented procedure for disabling encryption. Administrators who > > just want to set something up and have it running would be protected, > > without needing to know that they need to go through the effort of finding > > the documentation and enabling encryption everywhere. > > Agreed. > > > I propose that the OpenAFS 1.8 major release introduce encryption by > > default, for all(*) connections, whether client-to-server or > > server-to-server. There would of course be knobs to disable encryption > > for sites which do not need it, but the default value would be "on". > > It is worth pointing out that the Windows client has defaulted to crypt > mode since I began working on it in 2003. If I had my way at the time > crypt mode would be required and not configurable. Still to this day I > hear from administrators that they have no need to security because the > cell is internal. This simply isn't true. It is not possible to keep > attackers out all of the time. If the major banks that spend billions > on IT cannot do it, neither can an organization that deploys OpenAFS. > > > In addition to feedback on the general proposal for encrypt-by-default, I > > would appreciate feedback on more detailed questions, which might shape > > the structure of an implementation: > > > > (1) Is it sufficient to have one single knob that controls all connections > > from a given host, whether cache manager or server? > > Unlikely. > > > (2) (Assuming that the answer to (1) is "no") Should there be separate > > knobs knob for intra-ubik connections, fileserver-to-ptserver, and > > volserver-to-volserver connections? > > One knob per service with a host configurable default. > > > (3) What downsides do you see as possible for a new text-based > > configuration file to control the various behaviors? (Looking forward, > > this could also be a place to configure selection of rxgk vs. rxkad.) > > The source tree imports the Heimdal krb5 profile configuration parser. > There was agreement at the last Pittsburgh hackathon on a format. Mike > Meffie was scribe. The AuriStor configuration is based upon that model > as presented at the CERN conference. OpenAFS should do the same. > > There should be a service configurable knob with a configurable default. > The default should be "crypt". > > > No decisions have been made; this thread is me seeking feedback from the > > community on an issue where I have an opinion but do not know the position > > of the community as a whole. > > I believe this is a topic in which every organization that deploys > OpenAFS should speak up. > > > > > Thank you, > > > > Ben > > > > > > (*) My current proposal affects mostly the cache manager; > > encryption-by-default for the standalong client tools (vos, pts, bos, > > etc.) would be configurable in a different way, presumably with a > > command-line option. > > At least some of the command line tools already have a -crypt option. > The Windows client enables crypt by default unless the cache manager's > crypt setting has been disabled. > > Jeffrey Altman > > > > -- ---------------------------------------------------------------------------- Troy Benjegerdes 'da hozer' [email protected] 7 elements earth::water::air::fire::mind::spirit::soul grid.coop Never pick a fight with someone who buys ink by the barrel, nor try buy a hacker who makes money by the megahash _______________________________________________ OpenAFS-devel mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-devel
