On Mon, 2010-09-27 at 15:25 -0400, Eric Paris wrote: > On Mon, 2010-09-27 at 14:29 -0400, Paul Moore wrote: > > On Mon, 2010-09-27 at 13:01 -0400, Eric Paris wrote: > > > On Mon, 2010-09-27 at 10:50 +1000, James Morris wrote: > > > > On Fri, 24 Sep 2010, Eric Paris wrote: > > > > > > > For the reasons above, I think the secctx string needs to be exported in > > > > addition to this rather than instead of. > > > > > > I won't argue, I don't agree with your reasoning, but I'm not opposed to > > > this result. We have 3 competing suggestions: > > > > > > Jan suggested we: > > > completely eliminate secmark from procfs+netlink and only export secctx > > > in netlink. > > > > > > Eric suggested we: > > > completely eliminate secmark from procfs+netlink and then export secctx > > > in procfs+netlink > > > > > > sounds like James suggested we: > > > continue to export meaningless and confusing secmark from procfs+netlink > > > and then export secctx in procfs+netlink as well. > > > > > > I'm going to implement James' idea and resend the patch series. Any > > > strong objections? > > > > I apologize for not getting a chance to look at these patches sooner. > > In general they look fine to me and my only real concern was addressed > > by Pablo already (breaking userspace due to #define changes). > > > > As far as exporting the 32bit secid/secmark to userspace, I think that > > is a mistake. James correctly points out that it does map to a LSM > > specific value, e.g. SELinux and Smack security labels, but I don't > > think he makes it clear that in the two LSMs that currently use secids > > the mapping between the secid and the secctx is not constant; the secids > > are transient values that will change with each boot in a manner that > > userspace can not predict. For this reason, I think exporting the > > secids is only going to cause users/admins grief, whereas exporting the > > associated secctx should be a much more stable value and is likely what > > the user/admin is expecting anyway. > > So it sounds to me like Paul agrees with me that exporting the SELinux > sid as 'secmark=' was a bad idea. It's the whole reason this thread > started, someone wanted to be able to translate and use that field (and > instantly realized it was useless.) > > I see it as having 3 options. lets assume was have a packet with > selinux sid=121 and selinux context=packet_t. We can > > 1) secmark=121 secctx=packet_t > This continues to send secmark like we do and people might continue to > be baffled by the 121. > > 2) secmark=1 secctx=packet_t > This sends a secmark field to userspace so if an application which > reads this exists (I doubt such an application actually exists in in the > real world) it will still get all of the information it got before but > noone will be baffled by what the number means. 1/0 is pretty obvious. > > 3) secctx=packet_t > Smallest easiest, what my patches actually do. Could theoretically > break some script that expected the field to be there, but any such > script is already broken since that field can be easily compiled > out...... > > James, if you are adamant about #1 I'll resend, otherwise I'm sticking > with #3..... James, if you do feel strongly about door #1, can you provide a good example of how someone might use the secid to do something useful in userspace? I ask because I can't think of anything and it would be nice to have the example on record for future work. -- paul moore linux @ hp -- To unsubscribe from this list: send the line "unsubscribe netfilter" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
